Institute of Fundamental Technological Research

Yap M., Bill C., Byra M., Ting-yu L., Huahu Y., Galdran A., Yung-Han C., Raphael B., Sven K., Friedrich C., Yu-wen L., Ching-hui Y., Kang L., Qicheng L., Ballester M., Carneiro G., Yi-Jen J., Juinn-Dar H., Pappachan J., Reeves N., Vishnu C., Darren D., Diabetic foot ulcers segmentation challenge report: Benchmark and analysis, Medical Image Analysis, ISSN: 1361-8415, DOI: 10.1016/j.media.2024.103153, Vol.94, No.103153, pp.1-14, 2024

Abstract:
Monitoring the healing progress of diabetic foot ulcers is a challenging process. Accurate segmentation of foot ulcers can help podiatrists to quantitatively measure the size of wound regions to assist prediction of healing status. The main challenge in this field is the lack of publicly available manual delineation, which can be time consuming and laborious. Recently, methods based on deep learning have shown excellent results in automatic segmentation of medical images, however, they require large-scale datasets for training, and there is limited consensus on which methods perform the best. The 2022 Diabetic Foot Ulcers segmentation challenge was held in conjunction with the 2022 International Conference on Medical Image Computing and Computer Assisted Intervention, which sought to address these issues and stimulate progress in this research domain. A training set of 2000 images exhibiting diabetic foot ulcers was released with corresponding segmentation ground truth masks. Of the 72 (approved) requests from 47 countries, 26 teams used this data to develop fully automated systems to predict the true segmentation masks on a test set of 2000 images, with the corresponding ground truth segmentation masks kept private. Predictions from participating teams were scored and ranked according to their average Dice similarity coefficient of the ground truth masks and prediction masks. The winning team achieved a Dice of 0.7287 for diabetic foot ulcer segmentation. This challenge has now entered a live leaderboard stage where it serves as a challenging benchmark for diabetic foot ulcer segmentation.

Keywords:
Deep learning, Diabetic foot ulcers, Segmentation, Convolutional neural networks

Orłowska-Gałęzia A. M., Graczykowski C., Pawłowski P. K., Ruta R., Rimasauskas M., Kuncius T., Majewska K., Mieloszyk M., Characterization of thermal expansion in additively manufactured continuous carbon fibre reinforced polymer composites using fibre Bragg grating sensors, MEASUREMENT, ISSN: 0263-2241, DOI: 10.1016/j.measurement.2024.114147, Vol.227, pp.114147-1-114147-15, 2024

Abstract:
This study investigates thermal strains in fibre reinforced polymeric samples manufactured using a modified Fused Deposition Modelling (FDM) method. The investigated material was a composition of polylactic acid (PLA) resin and continuous carbon fibres. Each test sample was equipped with two Bragg grating (FBG) sensors, one embedded inside and the other bonded to the surface. Both sensors monitored temperature-induced deformations
during the conditioning of the specimens in a thermal chamber. Multiscale, analytical and finite element method based models were implemented to quantify the temperature deformations. Research has revealed that in investigated samples, bending occurs due to thermal loading. This can result in an inaccurate estimation of the coefficient of thermal expansion when relying on surface deformation measurements. A proposed solution involves the use of one FBG sensor embedded inside the specimen or two FBG sensors placed symmetrically, capable of measuring axial thermal deformation and averaging the effects associated
with bending.

Keywords:
Continuous Carbon Fibre Reinforced Polymer Composites, Fibre Bragg gratings, Thermal expansion , Additive manufacturing, Multiscale modelling

Dobrzański J., Stupkiewicz S., Towards a sharper phase-field method: A hybrid diffuse–semisharp approach for microstructure evolution problems, COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING, ISSN: 0045-7825, DOI: 10.1016/j.cma.2024.116841, Vol.423, No.116841, pp.1-23, 2024

Abstract:
A new approach is developed for computational modelling of microstructure evolution problems. The approach combines the phase-field method with the recently-developed laminated element technique (LET) which is a simple and efficient method to model weak discontinuities using non-conforming finite-element meshes. The essence of LET is in treating the elements that are cut by an interface as simple laminates of the two phases, and this idea is here extended to propagating interfaces so that the volume fraction of the phases and the lamination orientation vary accordingly. In the proposed LET-PF approach, the phase-field variable (order parameter), which is governed by an evolution equation of the Ginzburg–Landau type, plays the role of a level-set function that implicitly defines the position of the (sharp) interface. The mechanical equilibrium subproblem is then solved using the semisharp LET technique. Performance of LET-PF is illustrated by numerical examples. In particular, it is shown that, for the problems studied, LET-PF exhibits higher accuracy than the conventional phase-field method so that, for instance, qualitatively correct results can be obtained using a significantly coarser mesh, and thus at a lower computational cost.

Keywords:
Microstructure evolution,Interfaces,Laminate,Phase-field method,Finite element method

Darban H., Elastostatics of nonuniform miniaturized beams: Explicit solutions through a nonlocal transfer matrix formulation, International Journal of Engineering Science, ISSN: 0020-7225, DOI: 10.1016/j.ijengsci.2024.104054, Vol.198, No.104054, pp.1-18, 2024

Abstract:
A mathematically well-posed nonlocal model is formulated based on the variational approach and the transfer matrix method to investigate the size-dependent elastostatics of nonuniform miniaturized beams. The beams are composed of an arbitrary number of sub-beams with diverse material and geometrical properties, as well as small-scale size dependency. The model adopts a stress-driven nonlocal approach, a well-established framework in the Engineering Science community. The curvature of a sub-beam is defined through an integral convolution, considering the bending moments across all cross-sections of the sub-beam and a kernel function. The governing equations are solved and the deflections are derived in terms of some constants. The formulation uses local and interfacial transfer matrices, incorporating continuity conditions at cross-sections where sub-beams are joined, to define relations between constants in the solution of a generic sub-beam and those of the first sub-beam at the left end. The boundary conditions are then imposed to derive an explicit, closed-form solution for the deflection. The solution significantly simplifies the study of nonuniform beams with multiple sub-beams. The predictions of the model for two limiting cases, namely local nonuniform and nonlocal uniform beams, are in excellent agreement with the available literature data. The flexural behavior of nonuniform miniaturized beams, composed of two to five different sub-beams and subjected to different boundary conditions, is studied. The results are presented and discussed, emphasizing the effects of the material properties, nonlocalities, and lengths of the sub-beams on the deflection. It is demonstrated that the flexural response of nonlocal nonuniform beams is more complex than local counterparts. Unlike the local beams, dividing a nonlocal uniform beam into multiple sub-beams and then reconnecting them changes the overall stiffness of the beam. The study highlights the potential to design nonuniform miniaturized beams with specific configurations to control their flexural response effectively.

Keywords:
Small-scale beam,Transfer matrix method,Multi-material,Size effect,MEMS,NEMS

Kalita D., Mulewska K., Jóźwik I., Zaborowska A., Gawęda M., Chromiński W., Bochenek K., Rogal Ł., Metastable β-Phase Ti–Nb Alloys Fabricated by Powder Metallurgy: Effect of Nb on Superelasticity and Deformation Behavior, METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, ISSN: 1073-5623, DOI: 10.1007/s11661-023-07285-5, pp.1-17, 2024

Abstract:
This study investigates the effect of Nb concentration on the mechanical properties, superelasticity, as well as deformation behavior of metastable β-phase Ti–Nb alloys produced via powder metallurgy. The alloys were fabricated through mechanical alloying, followed by consolidation using hot pressing. The resulting microstructure comprises fine β-phase grains with TiC carbide precipitates at the grain boundaries. The study reveals non-linear variations in the values of yield strength for the manufactured materials, which were attributed to the occurrence of various deformation mechanisms activated during the loading. It was found that the mechanisms change with the increasing concentration of Nb in the manner: stress-induced martensitic transformation, twinning, slip. However, all these mechanisms were activated at a reduced concentration of Nb compared to the materials obtained by casting technology previously reported in the literature. This is most probably associated with the elevated oxygen content, which affects the stability of the parent β-phase. The study revealed that superelasticity in Ti–Nb-based alloys prepared using powder metallurgy may be achieved by reducing the content of β-stabilizing elements compared to alloys obtained by conventional technologies. In this study, the Ti–14Nb (at. pct) alloy exhibited the best superelasticity, whereas conventionally fabricated Ti–Nb alloys displayed superelasticity at an Nb concentration of approximately 26 at. pct. The developed material exhibited a non-conventional, one-stage yielding behavior, resulting in a superelastic response at significantly higher stresses compared to conventionally fabricated Ti–Nb alloys.

Gambin B. J., Kruglenko E., Tymkiewicz R., Litniewski J., Heating efficiency of agarose samples doped with magnetic nanoparticles subjected to ultrasonic and magnetic field, INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, ISSN: 0017-9310, DOI: 10.1016/j.ijheatmasstransfer.2024.125467, Vol.226, No.125467, pp.1-10, 2024

Abstract:
Recently, magneto-ultrasound heating of tissue in the presence of magnetic nanoparticles (NPs) has been studied due to its high potential for use in oncological hyperthermia. It has been published that a synergistic effect, generation of additional heat caused by magneto-ultrasonic coupling, was observed in a tissue-mimicking material (TMM) enriched with magnetic NPs. The specific absorption rate (SAR) was determined from the temperature rise measurements in a focus of the ultrasound beam. It is important to use precise measurement methods when considering medical applications, for which there are limitations to the power of each field, resulting from the prevention of biological phenomena dangerous to the patient. This study demonstrates that in magneto-ultrasonic heating SAR can be measured much more accurately if the ultrasonic field is almost uniform. Measurements were performed on TMM containing Fe3O4 NPs with a diameter of approximately 8 nm and superparamagnetic properties. Both, the measurement and simulation results showed that the errors resulting from the inaccuracy of placing the temperature probe are smaller than in the case of the focused ultrasound. At the same time, the temperature increase caused by the ultrasonic field is almost linear and the influence of heat convection on the SAR determination is negligible. The measurements showed that magneto-ultrasonic hyperthermia can provide the desired thermal effect at lower ultrasound powers and magnetic fields compared to ultrasonic or magnetic hyperthermia used alone. No synergy effect was recorded.

Keywords:
Magnetic nanoparticle-mediated hyperthermia, Dual-mode ultrasonic-magnetic hyperthermia, Specific absorption rate, Hyperthermia efficiency

Marszałek A., Burczyński T., Modeling of limit order book data with ordered fuzzy numbers, APPLIED SOFT COMPUTING, ISSN: 1568-4946, DOI: 10.1016/j.asoc.2024.111555, Vol.158, pp.1-20, 2024

Abstract:
This paper presents a novel approach to representing the Limit Order Book data at a given timestamp using the Ordered Fuzzy Numbers concept. The limit order book contains all buy and sell orders placed by investors, updated in real-time, for the most liquid securities, even several hundred times a minute. Due to its irregular nature (different and dynamic changes in the number of buy and sell orders), direct calculations on the order book data are not feasible without transforming it into feature vectors. Currently, most studies use a price level-based data representation scheme when applying deep learning models on limit order book data. However, this scheme has limitations, particularly its sensitivity to subtle perturbations that can negatively impact model performance. On the other hand, the ordered fuzzy number is a mathematical object (a pair of two functions) used to process imprecise and uncertain data. Ordered Fuzzy Numbers possess well-defined arithmetic properties. Converting the limit order book data to ordered fuzzy numbers allows the creation of a time series of ordered fuzzy numbers (order books) and use them for further calculations, e.g., to represent input data for deep learning models or employing the concept of fuzzy time series in various domains, such as defining liquidity measures based on limit order book data. In this paper, the proposed approach is tested using one-year market data from the Polish Stock Exchange for the five biggest companies. The DeepLOB model is employed to predict mid-price movement using different input data representations. The proposed representation of Limit Order Book data demonstrated remarkably stable out-of-sample prediction accuracy, even when subjected to data perturbation.

Keywords:
Limit order book, Ordered fuzzy number, High-frequency forecasting, Mid-price, Data perturbation

Pisarski D., Jankowski Ł., Decentralized modular semi-active controller for suppression of vibrations and energy harvesting, JOURNAL OF SOUND AND VIBRATION, ISSN: 0022-460X, DOI: 10.1016/j.jsv.2024.118339, Vol.577, pp.118339-1-118339-20, 2024

Abstract:
The study investigates the problem of decentralized semi-active control of free vibration. The control scheme is designed for implementation in a modular controller architecture, where a collection of subcontrollers is employed, with each subcontroller being associated with a subsystem that represents a component of the vibrating structure. Each subcontroller uses state feedback from adjacent subsystem sensors to perform vibration suppression and energy harvesting using a switching control law. Furthermore, the assumption is made that neighbouring subcontrollers exchange information collaboratively to estimate the effects of coupling forces, achieving control efficiency comparable to that of a centralized approach. The effectiveness of the proposed approach is demonstrated on a modular suspension platform equipped with semi-active dampers and electromagnetic energy harvesters. The approach is evaluated under various free vibration scenarios, encompassing faulty measurement conditions, and is compared to passive and heuristic state-feedback control strategies. The results confirm that the proposed method attains a superior control performance, independent of the degree of decentralization in the adopted controller architecture, rendering it a viable solution for addressing large-scale semi-active control problems.

Keywords:
Vibration control,Energy harvesting,Adaptive control,Semi-active control,Decentralized controller

Tauzowski P., Błachowski B., Lógó J., Optimal topologies considering fatigue with reliability constraint, Advances in Engineering Software, ISSN: 0965-9978, DOI: 10.1016/j.advengsoft.2023.103590, Vol.189, pp.1-12, 2024

Abstract:
This paper addresses a challenging engineering problem that combines stress-limited topology optimization, reliability analysis, and plasticity-based low-cycle fatigue. Each of these issues represents a complex problem on its own, necessitating significant computational effort. In this study, we propose a novel approach that integrates safety assessment into the topology optimization process while considering the number of cycles for low-cycle fatigue. Our method employs a linear approximation of the performance function for safety control, incorporating the number of failure cycles within a complex, multi-level load program. The methodology is validated through real experiments, using a finite element model with cubic shape functions that yield nearly identical results between numerical and experimental outcomes in the case of fatigue-resistant design for a bi-axially tensioned structural joint.

Keywords:
Topology optimization, stress constraints, Reliability analysis, low-cycle fatigue, fatigueplasticity

Kaszyca K., Marcin C., Bucholc B., Błyskun P., Nisar F., Rojek J., Zybała R., Using the Spark Plasma Sintering System for Fabrication of Advanced Semiconductor Materials , Materials, ISSN: 1996-1944, DOI: 10.3390/ma17061422, Vol.17, No.1422, pp.1-15, 2024

Abstract:
The interest in the Spark Plasma Sintering (SPS) technique has continuously increased over the last few years. This article shows the possibility of the development of an SPS device used for material processing and synthesis in both scientific and industrial applications and aims to present manufacturing methods and the versatility of an SPS device, presenting examples of processing Arc-Melted- (half-Heusler, cobalt triantimonide) and Self-propagating High-temperature Synthesis (SHS)-synthesized semiconductor (bismuth telluride) materials. The SPS system functionality development is presented, the purpose of which was to broaden the knowledge of the nature of SPS processes. This approach enabled the precise design of material sintering processes and also contributed to increasing the repeatability and accuracy of sintering conditions.

Keywords:
spark plasma sintering, arc melting, semiconductor materials, half-Heusler, bismuth telluride, cobalt triantimonide, SHS, SPS

Kaczmarek A., Wisniewska A., Mościcki T. P., Hoffman J., The Luminescence of Laser-Produced Carbon Nanodots: The Effect of Aggregation in PEI Solution, Materials, ISSN: 1996-1944, DOI: 10.3390/ma17071573, Vol.17, No.7, pp.1-15, 2024

Abstract:
Carbon nanodots (CNDs) produced in pure water by the ablation of graphite with a nanosecond laser pulse exhibit weak photoluminescence. A small addition of polyethyleneimine (PEI) to the aqueous suspension of CNDs causes a significant increase in emissions. This paper presents experimental and theoretical studies of the emission properties of CND/PEI systems. The obtained CNDs responded to even trace amounts of PEI in solution (~0.014% v/v), resulting in a significant increase in the initial weak blue emission of CNDs and PEI taken separately. Morphology and size measurements showed that particle aggregation occurred in the presence of the polymer. A decrease in the calculated Stokes shift values was observed with increasing PEI content in the solution. This indicates a reduction in the number of non-radiative transitions, which explains the increase in the emission intensity of the CND/PEI systems. These results therefore confirmed that the increase in the emission of CND/PEI systems is caused by particle aggregation. Kinetic studies proved that the process is controlled mainly by diffusion, the initial stage of which has a dominant influence on determining the optical properties of the system.

Keywords:
aggregation-induced emission, carbon nanodots, polyethyleneimine, intrinsic fluorescence, adsorption kinetic study

Strojny-Nędza A., Pietrzak K. Z., Jóźwik I., Bucholc B., Wyszkowska E., Kurpaska Ł., Grabias A., Malinowska A., Chmielewski M., Effect of Nitrogen Atmosphere Annealing of Alloyed Powders on the Microstructure and Properties of ODS Ferritic Steels, Materials, ISSN: 1996-1944, DOI: 10.3390/ma17081743, Vol.17, No.8, pp.1-19, 2024

Abstract:
Oxide Dispersion Strengthened (ODS) ferritic steels are promising materials for the nuclear power sector. This paper presents the results of a study on the sintering process using the Spark Plasma Sintering (SPS) technique, focusing on ODS ferritic steel powders with different contents (0.3 and 0.6 vol.%) of Y2O3. The novelty lies in the analysis of the effect of pre-annealing treatment on powders previously prepared by mechanical alloying on the microstructure, mechanical, and thermal properties of the sinters. Using the SPS method, it was possible to obtain well-densified sinters with a relative density above 98%. Pre-annealing the powders resulted in an increase in the relative density of the sinters and a slight increase in their thermal conductivity. The use of low electron energies during SEM analysis allowed for a fairly good visualization of the reinforcing oxides uniformly dispersed in the matrix. Analysis of the Mössbauer spectroscopy results revealed that pre-annealing induces local atomic rearrangements within the solid solution. In addition, there was an additional spectral component, indicating the formation of a Cr-based paramagnetic phase. The ODS material with a higher Y2O3 content showed increased Vickers hardness values, as well as increased Young’s modulus and nanohardness, as determined by nanoindentation tests.

Keywords:
spark plasma sintering, ODS ferritic steel, mechanical alloying, Mössbauer spectroscopy, nanoindentation

Loayza-Aguilar Rómulo E., Carhuapoma-Garay J., Ramos-Falla K., Saldaña-Rojas Guillermo B., Huamancondor-Paz Yolanda P., Campoverde-Vigo L., Merino F., Olivos-Ramirez Gustavo E., Epibionts affect the growth and survival of Argopecten purpuratus (Lamarck, 1819) cultivated in Samanco Bay, Peru, Aquaculture, ISSN: 0044-8486, DOI: 10.1016/j.aquaculture.2023.740042, Vol.578, pp.740042-1-10, 2024

Abstract:
Argopecten purpuratus, a mollusk very cultivated in Peru, is a species whose ecological relations with respect to the epibionts that colonize it are not well known. For that reason, the objective of this research was to determine the effect of epibionts on valvar growth, total weight, gonad weight, adductor muscle weight, and survival of this cultured species in Samanco Bay. Four lanterns of 2 m and 10 floors were placed with 25 organisms, of 7 cm each, per floor, in two treatments: with epibiont removal (T1) and without removal (T2). The data was obtained after harvest, and the epibiont species on the right and left valves were identified and quantified in T1 and T2. In addition, the Absolute Growth Rate (AGR) was calculated for the meristic records, and the t Student test was applied to compare averages. Furthermore, mortality was recorded at harvest. The analyses allowed the identification of 43 epibiont species, 3 of them endolithic. The greatest biomass is of filter feeders: 70.1% in T1 and 90.9% in T2, and concentrated in 4 species, with limited development in T1. The biomass on the right valve at T1 and T2 represented 80.7 and 151.8% of the weight of the organism, respectively, and on the left valve 89.3 and 95.1%. All Absolute Growth Rates at T1 were higher than at T2, although without statistical significance. Mortality at T1 and T2 was negligible. This research has determined that the epibionts S. patagonicus, C. intestinalis, Hidroydes sp., and B. neritina, qualified as engineered species, are the predominant species on A. purpuratus in suspended cultures. Likewise, treatments with epibiont removal showed a lower development of these and 39 other associated species of lesser importance in terms of number and biomass. Our results allow us to infer that the development of epibionts can generate important stress in A. purpuratus, resulting in losses in the profitability of companies dedicated to this activity.

Keywords:
Argopecten purpuratus, Aquaculture, Epibiosis, Biofouling, Bivalve

Nwaji N., Juyong G., My‐Chi N., Huu‐Quang N., Hyojin K., Youngeun C., Youngmi K., Hongxia C., Jaebeom L., Emerging potentials of Fe-based nanomaterials for chiral sensing and imaging, Medicinal Research Review, ISSN: 1098-1128, DOI: 10.1002/med.22003, pp.Journal of Medicinal Research-22003, 2024

Abstract:
Fe-based nanostructures have possessed promising properties that make it suitable for chiral sensing and imaging applications owing to their ultra-small size, non-toxicity, biocompatibility, excellent photostability, tunable fluorescence, and water solubility. This review summarizes the recent research progress in the field of Fe-based nanostructures and places special emphases on their applications in chiral sensing and imaging. The synthetic strategies to prepare the targeted Fe-based structures were also introduced. The chiral sensing and imaging applications of the nanostructures are discussed in details.

Pawłowska A., Ćwierz-Pieńkowska A., Domalik A., Jaguś D., Kasprzak P., Matkowski R., Fura , Nowicki A., Żołek N.S., Curated benchmark dataset for ultrasound based breast lesion analysis, Scientific Data, ISSN: 2052-4463, DOI: 10.1038/s41597-024-02984-z, Vol.11, No.148, pp.1-13, 2024

Abstract:
A new detailed dataset of breast ultrasound scans (BrEaST) containing images of benign and malignant lesions as well as normal tissue examples, is presented. The dataset consists of 256 breast scans collected from 256 patients. Each scan was manually annotated and labeled by a radiologist experienced in breast ultrasound examination. In particular, each tumor was identified in the image using a freehand annotation and labeled according to BIRADS features and lexicon. The histopathological classification of the tumor was also provided for patients who underwent a biopsy.
The BrEaST dataset is the first breast ultrasound dataset containing patient-level labels, image-level annotations, and tumor-level labels with all cases confirmed by follow-up care or core needle biopsy result. To enable research into breast disease detection, tumor segmentation and classification, the BrEaST dataset is made publicly available with the CC-BY 4.0 license.

Pietrzyk-Thel P., Jain A., Bochenek K., Michalska M., Basista M. A., Szabo T., Nagy P., Wolska A., Klepka M., Flexible, tough and high-performing ionogels for supercapacitor application, Journal of Materiomics, ISSN: 2352-8478, DOI: 10.1016/j.jmat.2024.01.008, pp.1-41, 2024

Abstract:
Ionogels are an attractive class of materials for smart and flexible electronics and are prepared from the combination of a polymer and ionic liquid which is entrapped in this matrix. Ionogels provide a continuous conductive phase with high thermal, mechanical, and chemical stability. However, because of the higher percentage of ionic liquids it is difficult to obtain an ionogel with high ionic conductivity and mechanical stability, which are very important from an application point of view. In this work, ionogel films with high flexibility, excellent ionic conductivity, and exceptional stability were prepared using polyvinyl alcohol as the host polymer matrix and 1-ethyl-3-methylimidazolium hydrogen sulfate as the ionic liquid using water as the solvent for energy storage application. The prepared ionogel films exhibited good mechanical stability along with sustaining strain of more than 100% at room temperature and low temperature, the ability to withstand twisting up to 360° and different bending conditions, and excellent ionic conductivity of 5.12 × 10−3 S/cm. The supercapacitor cell fabricated using the optimized ionogel film showed a capacitance of 39.9 F/g with an energy and power densities of 5.5 Wh/kg and 0.3 kW/kg, respectively confirming the suitability of ionogels for supercapacitor application.

Keywords:
Ionic liquid, Gel polymer electrolyte, Ionic conductivity, 1-Ethyl-3-methylimidazolium hydrogen sulfate, Supercapacitors

Chandan D., Tulja Varun K., Miller M., Streltsov A., Entanglement catalysis for quantum states and noisy channels, Quantum 8, ISSN: 2521-327X, DOI: 10.22331/q-2024-03-20-1290, Vol.8, pp.1-20, 2024

Abstract:
Many applications of the emerging quantum technologies, such as quantum teleportation and quantum key distribution, require singlets, maximally entangled states of two quantum bits. It is thus of utmost importance to develop optimal procedures for establishing singlets between remote parties. As has been shown very recently, singlets can be obtained from other quantum states by using a quantum catalyst, an entangled quantum system which is not changed in the procedure. In this work we take this idea further, investigating properties of entanglement catalysis and its role for quantum communication. For transformations between bipartite pure states, we prove the existence of a universal catalyst, which can enable all possible transformations in this setup. We demonstrate the advantage of catalysis in asymptotic settings, going beyond the typical assumption of independent and identically distributed systems. We further develop methods to estimate the number of singlets which can be established via a noisy quantum channel when assisted by entangled catalysts. For various types of quantum channels our results lead to optimal protocols, allowing to establish the maximal number of singlets with a single use of the channel.

Barros G., Andre P., Rojek J., Carter J., Thoeni K., Time domain coupling of the boundary and discrete element methods for 3D problems, COMPUTATIONAL MECHANICS, ISSN: 0178-7675, DOI: 10.1007/s00466-024-02455-7, pp.1-19, 2024

Abstract:
This paper presents an extension of the authors’ previously developed interface coupling technique for 2D problems to 3D problems. The method combines the strengths of the Discrete Element Method (DEM), known for its adeptness in capturing discontinuities and non-linearities at the microscale, and the Boundary Element Method (BEM), known for its efficiency in modelling wave propagation within infinite domains. The 3D formulation is based on spherical discrete elements and bilinear quadrilateral boundary elements. The innovative coupling methodology overcomes a critical limitation by enabling the representation of discontinuities within infinite domains, a pivotal development for large-scale dynamic problems. The paper systematically addresses challenges, with a focus on interface compatibility, showcasing the method’s accuracy through benchmark validation on a finite rod and infinite spherical cavity. Finally, a model of a column embedded into the ground illustrates the versatility of the approach in handling complex scenarios with multiple domains. This innovative coupling approach represents a significant leap in the integration of DEM and BEM for 3D problems and opens avenues for tackling complex and realistic problems in various scientific and engineering domains.

Keywords:
Interface coupling, Concurrent multi-scale coupling, Boundary element method (BEM), Discrete element method (DEM) , Staggered time integration, Dynamic wave propagation, Infinite domain

Maździarz M., Nosewicz S., Atomistic investigation of deformation and fracture of individual structural components of metal matrix composites, ENGINEERING FRACTURE MECHANICS, ISSN: 0013-7944, DOI: 10.1016/j.engfracmech.2024.109953, Vol.298, pp.109953-1-109953-21, 2024

Abstract:
This paper focuses on the development of the atomistic framework for determining the lower scale mechanical parameters of single components of a metal matrix composite for final application to a micromechanical damage model. Here, the deformation and failure behavior of NiAl–Al2O3 interfaces and their components, metal and ceramic, are analyzed in depth using molecular statics calculations. A number of atomistic simulations of strength tests, uniaxial tensile, uniaxial compressive and simple shear, have been performed in order to obtain a set of stiffness tensors and strain–stress characteristics up to failure for 30 different crystalline and amorphous systems. Characteristic points on the strain–stress curves in the vicinity of failure are further analyzed at the atomistic level, using local measures of lattice disorder. Numerical results are discussed in the context of composite damage at upper microscopic scale based on images of the fracture surface of NiAl–Al2O3 composites.

Keywords:
Metal-matrix composites (MMCs), Fracture, Computational modeling, Mechanical testing, Molecular statics

Kucharski S. J., Maj M., Ryś M., Petryk H. M., Size effects in spherical indentation of single crystal copper, INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES, ISSN: 0020-7403, DOI: 10.1016/j.ijmecsci.2024.109138, Vol.272, pp.1-15, 2024

Keywords:
Hardness, Lattice rotation, Plasticity, Strain Gradient

Rybak D., Rinoldi C., Nakielski P., Du J., Haghighat Bayan Mohammad A., Zargarian Seyed S., Pruchniewski M., Li X., Strojny-Cieślak B., Ding B., Pierini F., Injectable and self-healable nano-architectured hydrogel for NIR-light responsive chemo- and photothermal bacterial eradication, JOURNAL OF MATERIALS CHEMISTRY B , ISSN: 2050-7518, DOI: 10.1039/D3TB02693K, pp.1-21, 2024

Abstract:
Hydrogels with multifunctional properties activated at specific times have gained significant attention in the biomedical field. As bacterial infections can cause severe complications that negatively impact wound repair, herein, we present the development of a stimuli-responsive, injectable, and in situ-forming hydrogel with antibacterial, self-healing, and drug-delivery properties. In this study, we prepared a Pluronic F-127 (PF127) and sodium alginate (SA)-based hydrogel that can be targeted to a specific tissue via injection. The PF127/SA hydrogel was incorporated with polymeric short-filaments (SFs) containing an anti-inflammatory drug – ketoprofen, and stimuli-responsive polydopamine (PDA) particles. The hydrogel, after injection, could be in situ gelated at the body temperature, showing great in vitro stability and self-healing ability after 4 h of incubation. The SFs and PDA improved the hydrogel injectability and compressive strength. The introduction of PDA significantly accelerated the KET release under near-infrared light exposure and extended its release validity period. The excellent composites’ photo-thermal performance led to antibacterial activity against representative Gram-positive and Gram-negative bacteria, resulting in 99.9% E. coli and S. aureus eradication after 10 min of NIR light irradiation. In vitro, fibroblast L929 cell studies confirmed the materials’ biocompatibility and paved the way toward further in vivo and clinical application of the system for chronic wound treatments.

Deshpande S., Bordas S., Lengiewicz J. A., MAgNET: A graph U-Net architecture for mesh-based simulations, Engineering Applications of Artificial Intelligence, ISSN: 0952-1976, DOI: 10.1016/j.engappai.2024.108055, Vol.133 B, No.108055, pp.1-18, 2024

Abstract:
In many cutting-edge applications, high-fidelity computational models prove to be too slow for practical use and are therefore replaced by much faster surrogate models. Recently, deep learning techniques have increasingly been utilized to accelerate such predictions. To enable learning on large-dimensional and complex data, specific neural network architectures have been developed, including convolutional and graph neural networks. In this work, we present a novel encoder–decoder geometric deep learning framework called MAgNET, which extends the well-known convolutional neural networks to accommodate arbitrary graph-structured data. MAgNET consists of innovative Multichannel Aggregation (MAg) layers and graph pooling/unpooling layers, forming a graph U-Net architecture that is analogous to convolutional U-Nets. We demonstrate the predictive capabilities of MAgNET in surrogate modeling for non-linear finite element simulations in the mechanics of solids.

Keywords:
Geometric deep learning, Mesh based simulations, Finite element method, Graph U-Net, Surrogate modeling

Moazzami Goudarzi Z., Zaszczyńska A., Kowalczyk T., Sajkiewicz P.Ł., Electrospun Antimicrobial Drug Delivery Systems and Hydrogels Used for Wound Dressings, Pharmaceutics, ISSN: 1999-4923, DOI: 10.3390/pharmaceutics16010093, Vol.16, No.1, pp.93-1-27, 2024

Abstract:
Wounds and chronic wounds can be caused by bacterial infections and lead to discomfort in patients. To solve this problem, scientists are working to create modern wound dressings with antibacterial additives, mainly because traditional materials cannot meet the general requirements for complex wounds and cannot promote wound healing. This demand is met by material engineering, through which we can create electrospun wound dressings. Electrospun wound dressings, as well as those based on hydrogels with incorporated antibacterial compounds, can meet these requirements. This manuscript reviews recent materials used as wound dressings, discussing their formation, application, and functionalization. The focus is on presenting dressings based on electrospun materials and hydrogels. In contrast, recent advancements in wound care have highlighted the potential of thermoresponsive hydrogels as dynamic and antibacterial wound dressings. These hydrogels contain adaptable polymers that offer targeted drug delivery and show promise in managing various wound types while addressing bacterial infections. In this way, the article is intended to serve as a compendium of knowledge for researchers, medical practitioners, and biomaterials engineers, providing up-to-date information on the state of the art, possibilities of innovative solutions, and potential challenges in the area of materials used in dressings.

Keywords:
wound dressings, drug delivery systems, thermoresponsive hydrogels

Haghighat Bayan Mohammad A., Rinoldi C., Rybak D., Zargarian Seyed S., Zakrzewska A., Cegielska O., Põhako-Palu K., Zhang S., Stobnicka-Kupiec A., Górny Rafał L., Nakielski P., Kogermann K., De Sio L., Ding B., Pierini F., Engineering surgical face masks with photothermal and photodynamic plasmonic nanostructures for enhancing filtration and on-demand pathogen eradication, Biomaterials Science, ISSN: 2047-4849, DOI: 10.1039/d3bm01125a, pp.1-15, 2024

Abstract:
The shortage of face masks and the lack of antipathogenic functions has been significant since the recent pandemic's inception. Moreover, the disposal of an enormous number of contaminated face masks not only carries a significant environmental impact but also escalates the risk of cross-contamination. This study proposes a strategy to upgrade available surgical masks into antibacterial masks with enhanced particle and bacterial filtration. Plasmonic nanoparticles can provide photodynamic and photothermal functionalities for surgical masks. For this purpose, gold nanorods act as on-demand agents to eliminate pathogens on the surface of the masks upon near-infrared light irradiation. Additionally, the modified masks are furnished with polymer electrospun nanofibrous layers. These electrospun layers can enhance the particle and bacterial filtration efficiency, not at the cost of the pressure drop of the mask. Consequently, fabricating these prototype masks could be a practical approach to upgrading the available masks to alleviate the environmental toll of disposable face masks.

Fathalian M., Postek E. W., Tahani M., Sadowski T., A Comprehensive Study of Al2O3 Mechanical Behavior Using Density Functional Theory and Molecular Dynamics, Molecules, ISSN: 1420-3049, DOI: 10.3390/molecules29051165, Vol.29, pp.1165-1165-18, 2024

Abstract:
This study comprehensively investigates Al2O3’s mechanical properties, focusing on fracture toughness, surface energy, Young’s modulus, and crack propagation. The density functional
theory (DFT) is employed to model the vacancies in Al2O3, providing essential insights into this material’s structural stability and defect formation. The DFT simulations reveal a deep understanding of vacancy-related properties and their impact on mechanical behavior. In conjunction with molecular dynamics (MD) simulations, the fracture toughness and crack propagation in Al2O3 are explored, offering valuable information on material strength and durability. The surface energy of Al2O3 is also assessed using DFT, shedding light on its interactions with the surrounding environment.
The results of this investigation highlight the significant impact of oxygen vacancies on mechanical characteristics such as ultimate strength and fracture toughness, drawing comparisons with the effects observed in the presence of aluminum vacancies. Additionally, the research underscores the validation of fracture toughness outcomes derived from both DFT and MD simulations, which align well with findings from established experimental studies. Additionally, the research underscores the validation of fracture toughness outcomes derived from DFT and MD simulations, aligning well with findings from established experimental studies. The combination of DFT and MD simulations provides a robust framework for a comprehensive understanding of Al2O3’s mechanical properties, with implications for material science and engineering applications.

Keywords:
Al2O3, fracture toughness, density functional theory, molecular dynamics

Nisar F., Rojek J., Nosewicz S., Kaszyca K., Chmielewski M., Evaluation of effective thermal conductivity of sintered porous materials using an improved discrete element model, POWDER TECHNOLOGY, ISSN: 0032-5910, DOI: 10.1016/j.powtec.2024.119546, Vol.437, pp.119546- , 2024

Abstract:
This work aims to revise and apply an original discrete element model (DEM) to evaluate effective thermal conductivity of sintered porous materials. The model, based on two-particle sintering geometry, calculates inter-particle neck using Constant Volume (CV) criterion. The model was validated using experimental measurements on sintered porous NiAl. For DEM simulations, heterogeneous samples with real particle size distribution and different densities were obtained by simulation of hot pressing. Neck size evaluated using Coble’s and CV models were compared to show that commonly used Coble’s model overestimates neck size and conductivity. The proposed model was improved by neck-size correction to compensate for non-physical overlaps at higher densities and by adding grain-boundary resistance to account for porosity within necks. Resistance contribution from grain boundaries was shown to decrease with increasing density. Thermal conductivity obtained from the improved model was close to experimental results, suggesting validity of the model.

Keywords:
Discrete element method,Effective thermal conductivity,Porous materials,Sintering,Heat conduction simulation

Kowalczyk-Gajewska K., Maj M., Bieniek K., Majewski M., Opiela K.C., Zieliński T.G., Cubic elasticity of porous materials produced by additive manufacturing: experimental analyses, numerical and mean-field modelling, ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING, ISSN: 1644-9665, DOI: 10.1007/s43452-023-00843-z, Vol.24, pp.34-1-34-22, 2024

Abstract:
Although the elastic properties of porous materials depend mainly on the volume fraction of pores, the details of pore distribution within the material representative volume are also important and may be the subject of optimisation. To study their effect, experimental analyses were performed on samples made of a polymer material with a predefined distribution of spherical voids, but with various porosities due to different pore sizes. Three types of pore distribution with cubic symmetry were considered and the results of experimental analyses were confronted with mean-field estimates and numerical calculations. The mean-field ‘cluster’ model is used in which the mutual interactions between each of the two pores in the predefined volume are considered. As a result, the geometry of pore distribution is reflected in the anisotropic effective properties. The samples were produced using a 3D printing technique and tested in the regime of small strain to assess the elastic stiffness. The digital image correlation method was used to measure material response under compression. As a reference, the solid samples were also 3D printed and tested to evaluate the polymer matrix stiffness. The anisotropy of the elastic response of porous samples related to the arrangement of voids was assessed. Young’s moduli measured for the additively manufactured samples complied satisfactorily with modelling predictions for low and moderate pore sizes, while only qualitatively for larger porosities. Thus, the low-cost additive manufacturing techniques may be considered rather as preliminary tools to prototype porous materials and test mean-field approaches, while for the quantitative and detailed model validation, more accurate additive printing techniques should be considered. Research paves the way for using these computationally efficient models in optimising the microstructure of heterogeneous materials and composites.

Keywords:
Pore configuration, Anisotropy, Elasticity, Micro-mechanics, Additive manufacturing

Witecka A., Pietrzyk-Thel P., Krajewski M., Sobczak K., Wolska A., Jain A., Preparation of activated carbon/iron oxide/chitosan electrodes for symmetric supercapacitor using electrophoretic deposition: A facile, fast and sustainable approach, JOURNAL OF ALLOYS AND COMPOUNDS, ISSN: 0925-8388, DOI: 10.1016/j.jallcom.2024.174040, Vol.985, No.174040, pp.1-15, 2024

Abstract:
In this research, electrophoretic deposition (EPD) was employed to prepare a porous composite film (ACF electrode) consisting of 90 wt% activated carbon particles, 10 wt% iron oxide nanoparticles, and a chitosan as binder in a facile, fast, and sustainable manner. This micro-mesoporous composite film, with a thickness of ∼45 µm and a surface area of ∼208.1 m2g−1, was coated on a stainless steel substrate. The SEM and TEM investigations proved the homogeneous distribution of carbon microparticles and iron oxide nanoparticles in the deposit, while the EDX, XRD, Raman spectroscopy, and XPS confirmed the chemical composition. ACF electrodes were also used in a symmetric two-electrode cell configuration with a sandwiched gel polymer electrolyte - PVdF(HFP)-PC-Mg(ClO4)2 and revealed a specific capacitance of ∼54.4 F g−1, along with satisfactory energy and power density of ∼4.7 Wh kg−1 and 1.2 kW kg−1, respectively, and excellent electrochemical stability up to ∼10,000 cycles (with merely 8.5% decay by the 5000th cycle). Obtained results confirmed the stability of the used system and its possible application in the field of energy storage and conversion.

Witecka A., Schmitt J., Courtien M., Gerardin C., Rydzek G., Hybrid mesoporous silica materials templated with surfactant polyion complex (SPIC) micelles for pH-triggered drug release, Microporous and Mesoporous Materials, ISSN: 1387-1811, DOI: 10.1016/j.micromeso.2023.112913, Vol.365, No.112913, pp.1-13, 2024

Abstract:
New Surfactant PolyIon Complex (SPIC) micelles were assembled by electrostatic complexation of an antibacterial cationic surfactant, cetylpyridinium chloride (CPC), and a double hydrophilic block copolymer (DHBC) containing a neutral comb block of poly(oligo(ethylene glycol)) methyl ether acrylate (PEOGA) and a weak polyacid block of poly(acrylic acid) (PAA). The corresponding SPIC micelles, with a CPC/PAA core and a PEOGA corona, were successfully used as structure directing and functionalizing agents in a soft and sustainable sol-gel strategy, yielding hybrid mesoporous silica (MS) materials with a monomodal pore size distribution centred at 2.8 nm. The influence of synthesis parameters, including the pH, concentrations and ratios of components, was systematically investigated. The obtained hybrid MS materials were intrinsically functional, with PEOGA blocks anchored in silica walls via H-bonding, while weak polyacid blocks, complexed with CPC, were confined within the mesopores. The response of the materials to pH changes (pH 7.4, 4.2 and 3) indicated remarkable stability of the anchored DHBC, while CPC was selectively released under the acidic conditions typical of orodental biofilm microenvironments. This result is noteworthy, since the release of encapsulated amphiphilic drugs into water is less favorable than that of hydrophilic drugs. Owing to the control of their pore and functionality properties, ordered hybrid silica materials templated and functionalized with SPIC systems will be materials of choice for developing pH-responsive biomedical devices using wet processing techniques

Keywords:
Double hydrophilic block copolymer, Cooperative self-assembly, Surfactant-polyion complex micelle, Stimuli-responsive nanomaterials, Sustainable, Sol-gel synthesis

Entezari E., Velazquez J., Lopez D., Zuniga M., Mousavisogolitappeh H., Davani R., Szpunar J., An experimental and statistical study on the characteristics of non-metallic inclusions that serve as hydrogen-induced crack nucleation sites in pipeline steel, Engineering Failure Analysis, ISSN: 1350-6307, DOI: 10.1016/j.engfailanal.2023.107695, Vol.154, No.107695, pp.1-15, 2024

Abstract:
This study consists of a statistical study to identify spatial distribution parameters of non-metallic inclusions (NMIs) at hydrogen-induced cracking (HIC) nucleation sites in both low-strength and high-strength steel pipes. The electrochemical cathodic charging method was used to induce HIC in pipeline steel plates, and the nucleation of the HIC was monitored using straight beam ultrasonic testing. Optical microscopy (OM) and scanning electron microscopy (SEM) were used to evaluate the shape, size, area fraction, and separation distance of NMIs. The hydrogen microprint technique (HMT), electron backscattered diffraction (EBSD) analysis, and finite element (FE) stress analysis were performed to characterize HIC nucleation sites. The findings showed that cubical and spinal NMIs, characterized by strong hydrogen trapping capacity due to high misfit strain and von Mises stress, are favored sites for HIC nucleation. The main finding of this study is that the shape and sharpness of NMIs are the factors that determine when NMIs will be a HIC nucleation site, rather than size, as generally accepted.

Keywords:
Hydrogen-induced cracking, Statistical study, Non-metallic inclusions, Hydrogen microprint technique, Finite element stress analysis

Ciurans-Oset M., Flasar P., Jenczyk P., Jarząbek D. M., Mouzon J., Akhtar F., Role of the microstructure and the residual strains on the mechanical properties of cast tungsten carbide produced by different methods, Journal of Materials Research and Technology, ISSN: 2238-7854, DOI: 10.1016/j.jmrt.2024.04.067, Vol.30, pp.3640-3649, 2024

Abstract:
Cast tungsten carbide (CTC) is a biphasic, pearlitic-like structure composed of WC lamellae in a matrix of W2C. Besides excellent flowability, spherical CTC powders exhibit superior hardness and wear resistance. Nevertheless, the available literature generally fails to explain the physical mechanisms behind such a phenomenon. In the present work, the microstructure and the mechanical properties of the novel centrifugally-atomized spherical CTC have been extensively investigated. This material exhibited an extremely fine microstructure, with WC lamellae of 27–29 nm in thickness and bulk lattice strains of 1.0–1.4 %, resulting in a microindentation hardness of 31.4 ± 1.6 GPa. The results of this study clearly show that centrifugally-atomized CTC is mechanically superior to both spheroidized CTC and conventional cast-and-crushed CTC. In addition, the effect of a series of heat treatments on the bulk fracture toughness and the fatigue life of entire CTC particles was also investigated. The reduction of residual stresses in the bulk of particles upon annealing dramatically increased the indentation fracture toughness, whereas the bulk microindentation hardness remained essentially unaffected. Regarding the fatigue life of entire particles under uniaxial cyclic compressive loading, local phase transformation phenomena at the surface of the particles upon heat treatment were concluded to play the most critical role. Indeed, the cumulative fatigue damage was minimized in surface-carburized CTC powders, where compressive stresses were induced at the outermost surface.

Keywords:
Cast tungsten carbide, Microindentation hardness, X-ray diffraction, Lattice microstrains, Dislocation density, Compression

Liu L., Sznajder P., Ekiel-Jeżewska M.L., Spectral analysis for elastica dynamics in a shear flow, Physical Review Fluids, ISSN: 2469-990X, DOI: 10.1103/PhysRevFluids.9.014101, Vol.9, No.1, pp.014101-1-12, 2024

Abstract:
We present the spectral analysis of three-dimensional dynamics of an elastic filament in a shear flow of a viscous fluid at a low Reynolds number in the absence of Brownian motion. The elastica model is used. The fiber initially is almost straight at an arbitrary orientation, with small perpendicular perturbations in the shear plane and out-of-plane. To analyze the stability of both perturbations, equations for the eigenvalues and eigenfunctions are derived and solved by the Chebyshev spectral collocation method. It is shown that their crucial features are the same as in the case of the two-dimensional elastica dynamics in shear flow [Becker and Shelley, Phys. Rev. Lett. 87, 198301 (2001)] and the three-dimensional elastica dynamics in the compressional flow [Chakrabarti et al., Nat. Phys. 16, 689 (2020)]. We find a similar dependence of the buckled shapes on the ratio of bending to hydrodynamic forces as in the simulations for elastic fibers of a nonzero thickness [Słowicka et al., New J. Phys. 24, 013013 (2022)].

Bandzerewicz A., Howis J., Wierzchowski K., Miroslav S., Jiri H., Denis P., Gołofit T., Pilarek M., Gadomska-Gajadhur A., Exploring the application of poly(1,2-ethanediol citrate)/polylactide nonwovens in cell culturing, Frontiers in Bioengineering and Biotechnology, ISSN: 2296-4185, DOI: 10.3389/fbioe.2024.1332290, Vol.12, pp.1-13, 2024

Abstract:
Biomaterials containing citric acid as a building unit show potential for use as blood vessel and skin tissue substitutes. The success in commercializing implants containing a polymer matrix of poly(1,8-octanediol citrate) provides a rationale for exploring polycitrates based on other diols. Changing the aliphatic chain length of the diol allows functional design strategies to control the implant’s mechanical properties, degradation profile and surface energy. In the present work, poly(1,2-ethanediol citrate) was synthesized and used as an additive to polylactide in the electrospinning process. It was established that the content of polycitrate greatly influences the nonwovens’ properties: an equal mass ratio of polymers resulted in the best morphology. The obtained nonwovens were characterized by surface hydrophilicity, tensile strength, and thermal properties. L929 cell cultures were carried out on their surface. The materials were found to be non-cytotoxic and the degree of porosity was suitable for cell colonization. On the basis of the most important parameters for assessing the condition of cultured cells (cell density and viability, cell metabolic activity and lactate dehydrogenase activity), the potential of PLLA + PECit nonwovens for application in tissue engineering was established.

Bandzerewicz A., Wierzchowski K., Mierzejwska J., Denis P., Gołofit T., Patrycja S., Pilarek M., Gadomska-Gajadhur A., Biological Activity of Poly(1,3-propanediol citrate) Films andNonwovens: Mechanical, Thermal, Antimicrobial, andCytotoxicity Studies, Macromolecular Rapid Communications, ISSN: 1521-3927, DOI: 10.1002/marc.202300452, Vol.45, pp.1-18, 2024

Abstract:
Polymers are of great interest for medical and cosmeceutical applications. Thecurrent trend is to combine materials of natural and synthetic origin in orderto obtain products with appropriate mechanical strength and goodbiocompatibility, additionally biodegradable and bioresorbable. Citric acid,being an important metabolite, is an interesting substance for the synthesis ofmaterials for biomedical applications. Due to the high functionality of themolecule, it is commonly used in biomaterials chemistry as a crosslinkingagent. Among citric acid-based biopolyesters, poly(1,8-octanediol citrate) isthe best known. It shows application potential in soft tissue engineering. Thiswork focuses on a much less studied polyester, poly(1,3-propanediol citrate).Porous and non-porous materials based on the synthesized polyesters areprepared and characterized, including mechanical, thermal, and surfaceproperties, morphology, and degradation. The main focus is on assessing thebiocompatibility and antimicrobial properties of the materials.

Keywords:
biomaterials, cell cultures, citric acid polyesters, electrospinning, , ,

Pawłowska S., Cysewska K., Ziai Y., Karczewski J., Jasiński P., Molin S., Influence of conductive carbon and MnCo2O4 on morphological and electrical properties of hydrogels for electrochemical energy conversion, Beilstein Journal of Nanotechnology, ISSN: 2190-4286, DOI: 10.3762/bjnano.15.6, pp.57-70, 2024

Keywords:
electrical properties, energy, hydrogel, hydrogen, oxygen evolution reaction, polymer composites

Dąbrowski M., Brachaczek A., Bogusz K., Glinicki M.A., Experimental assessment of appropriate time for aggregate exposure at the surface of cement concrete pavement, International Journal of Pavement Engineering, ISSN: 1029-8436, DOI: 10.1080/10298436.2024.2318607, Vol.25, No.1, pp.1-12, 2024

Abstract:
Exposed aggregate concrete (EAC) pavement is a commonly employed technology in Europe for the construction of highways. The technical challenges associated with pavement construction include achieving both a comfortable ride and the desired skid resistance, while ensuring the long-term concrete durability. Maintaining uniformity of concrete mix, precise dosing of retarding agents, optimal selection of brushing time, and ensuring adequate curing conditions are identified as critical factors for achieving the designed ride performance. This study is focused on determining the appropriate time for the brushing operation, conducted to expose aggregate grains at the surface of the pavement. Laboratory tests were performed on concrete mixes designed to replicate job mixes for the upper layer of a two-layer concrete pavement. Measurements of the mass of evaporated water from the cement paste, isothermal calorimetry tests, and modified Vicat tests were employed to predict the appropriate brushing time. The texture depth was determined using a laser profiler as a function of brushing time. Compressive strength, the rate of chloride ion migration, and scaling resistance were determined through tests conducted on specimens cut from exposed aggregate slabs. Results revealed the suitability of the developed test method for determining the appropriate time for brushing EAC pavements.

Keywords:
cement setting, exposed aggregate concrete, macrotexture, pavement durability, surface retarder, texturing technology

Kopeć M., Gunputh U., Macek W., Kowalewski Z.L., Wood P., Orientation effects on the fracture behaviour of additively manufactured stainless steel 316L subjected to high cyclic fatigue, Theoretical and Applied Fracture Mechanics, ISSN: 0167-8442, DOI: 10.1016/j.tafmec.2024.104287, pp.1-20, 2024

Abstract:
In this paper, stainless steel 316L (SS316L) bars were additively manufactured (AM) in three orientations (Z – vertical, XY – horizontal, ZX45 – midway between vertical and horizontal) by using the Laser Powder Bed Fusion Melting (LPBF-M) method. The AM specimens were subjected to load control fatigue testing under full tension and compression (R = -1) at stress amplitudes ±350, ±400 and ±450 MPa. The XY and ZX45 printing orientations were found to significantly improve service life. Although similar strain response was found for each orientation when the same stress amplitude was applied, slightly different fracture mechanisms were identified during the post-mortem surface observations.

Keywords:
SS316L,stainless steel,fatigue,additive manufacturing,Laser Powder Bed Fusion Melting (LPBF-M)

Nwaji N., Getasew Mulualem Z., Juyong G., Hyojin K., Lemma Tushome T., Yujin C., Mahedra G., Hyeyoung S., Jaebeom L., Dimeric NiCo single-atom anchored on ultrathin N-doped 2D molybdenum carbide boosted performance in solid-state supercapacitor, Journal of Energy Storage, ISSN: 2352-152X, DOI: 10.1016/j.est.2024.110671, Vol.83, pp.Journal of Energy Storage-110671, 2024

Abstract:
Tuning the electronic structure of single-atom catalysts through dimeric single-atom formation could be an innovative approach to increasing their energy storage activity, but the process of achieving this is challenging. In this study, we designed a simple technique to obtain Nisingle bondCo single atom dimers (SADs) anchored on N-doped molybdenum carbide (N-Mo2C) through in-situ encapsulation of Nisingle bondCo into molybdenum polydopamine, followed by annealing with optimal tuning of nitrogen dopant. The Nisingle bondCo atomic level coordination was confirmed with X-ray absorption spectroscopy. When used as energy storage supercapacitor, The NiCo-SADs showed enhanced specific capacity (1004.8 F g−1 at 1 A g−1), enhanced rate capability (75 %), and exceptional cycling stability (93.6 % with 98.5 % coulombic efficiency) via a dominant capacitive charge storage. The augmented charge storage characteristics are attributed to the collaborative features of the active Nisingle bondCo constituents acting as electron reservoir for effective adsorption of HO− ion during the electrochemical process. The DFT study showed thermodynamically favorable OH− adsorption between the three metal bridges that promoted redox reaction kinetics and enhanced conductivity for the NiCo-SADs. When using N-Mo2C as the anode to fabricate hybrid supercapacitors, the device exhibits high energy density of 69.69 Wh kg−1 at power density of 8200 W kg−1, respectively and shows excellent long-term cycling stability (93.42 % after 3000 cycles), which affirms the potential of the assembled device for applications in solid state supercapacitors.

Gaurav A., Das A., Paul A., Jain A., Boruah B., Jalebi M., Could halide perovskites revolutionalise batteries and supercapacitors: A leap in energy storage, Journal of Energy Storage, ISSN: 2352-152X, DOI: 10.1016/j.est.2024.111468, Vol.88, No.111468, pp.1-22, 2024

Abstract:
Metal halide perovskites have rapidly emerged as a revolutionary frontier in materials science, catalyzing breakthroughs in energy storage technology. Originating as transformative entities in the field of solar cells, these perovskites have surpassed conventional boundaries. This comprehensive review embarks on a journey through the intriguing potentials of energy storage, driven by the exceptional properties of perovskite materials. We delve into three compelling facets of this evolving landscape: batteries, supercapacitors, and the seamless integration of solar cells with energy storage. In the realm of batteries, we introduce the utilization of perovskites, with a specific focus on both lead and lead-free halide perovskites for conciseness. Leveraging superior electrical properties such as high ionic conductivity (ranging from 10−3 to 10−4 Scm−1 for Li-ion) and diverse structural dimensions coupled with remarkable diffusion coefficients (2.68 × 10−8 cm2s−1 and 3.63 × 10−9 cm2s−1) for Chloride and Iodide-based halide perovskites, respectively, we explore the immense potential of perovskites as electrodes compared to other host materials such as layered oxide, carbon, etc., specifically for Al-ion, Zn-ion, and Li-ion batteries application, paving the way for the next generation of energy storage devices. In the domain of supercapacitors, we discuss the application of halide perovskites, highlighting both their advantages and limitations. We also provide a brief overview of the significant progress made in the supercapacitor domain using perovskite materials over the years. Additionally, we venture into unexplored territories, emphasizing the potential integration of solar cells and energy storage systems, delving into innovative concepts such as photo-accelerated capacitors/supercapacitors and photo-accelerated batteries. Importantly, we presented a detailed analysis of the impact of the perovskite composition on different energy storage applications. Ultimately, we outline the significant advantages, recognize the existing limitations, and stimulate imagination concerning the boundless future potential of halide perovskites in the energy storage domain, fostering a scientific and innovative perspective that contributes to the ongoing research and practical application of perovskite materials.

Keywords:
Metal halide perovskite, Energy storage, Battery, Supercapacitors, Perovskite solar cells-batteries

Lisowski P., Glinicki M.A., Novel Processing Methods of Low-Clinker Multi-Component Cementitious Materials—A Review, Applied Sciences, ISSN: 2076-3417, DOI: 10.3390/app14020899, Vol.14(2), No.899, pp.1-28, 2024

Abstract:
The wide use of multi-component cement of highly reduced Portland clinker factor is largely impeded by detrimental changes in the rheological properties of concrete mixes, a substantial reduction in the early rate of cement hardening, and sometimes the insufficient strength of mature concrete. Therefore, major changes are needed in traditional concrete-production technologies if low-clinker cement is to gain wider acceptance. This review’s goal is to summarize the impacts of using non-ionizing radiation methods to improve the dispersion of concrete mix constituents, cement setting, and early hardening. The potential impacts of such interactions on the permeability and strength of concrete are also highlighted and investigated. Their intriguing potential for delivering additional energy to cementitious mixtures is analyzed for batch water, solid non-clinker constituents of cement (mainly supplementary cementitious materials), and their mixtures with aggregates. The advantages of adopting these non-traditional methods are found to be highly alluring to the greener preparation techniques used in the construction materials sector.

Keywords:
concrete mixing technology,early-age properties,low-clinker multi-component cement,magnetized water,microwave treatment,non-clinker constituents,ultrasound treatment

Zhang Y., Nwaji N.^♦, Wu L., Jin m., Zhou G., Giersig M., Wang X., Qiu T., Akinoglu E.M., MAPbBr3/Bi2WO6 Z-scheme-Heterojunction Photocatalysts for photocatalytic CO2 reduction, JOURNAL OF MATERIALS SCIENCE, ISSN: 0022-2461, DOI: 10.1007/s10853-023-09220-w, Vol.59, pp.Journal of Material Science-1498-1512, 2024

Abstract:
Photocatalytic CO2 reduction has emerged as a promising strategy for converting solar energy into valuable chemicals, capturing the attention of scientists across various disciplines. Organic and inorganic perovskites, particularly methylammonium lead bromide (MAPbBr3), have demonstrated potential in this field due to their remarkable visible-light response and carrier transport properties. However, the catalytic performance of pristine MAPbBr3 has been limited by severe charge recombination, hindering its applicability in photocatalytic systems. Here, we show that a MAPbBr3/Bi2WO6 (MA/BWO) heterojunction significantly enhances photocatalytic CO2 reduction performance compared to individual pristine MA or BWO. This enhancement is evidenced by the superior performance of the 25% MA/BWO composite, which exhibits CO and CH4 release rates of 1.82 μmol/g/h and 0.08 μmol/g/h, respectively. This improvement is attributed to the direct Z-scheme heterojunction formed between MAPbBr3 and Bi2WO6, which facilitates efficient charge separation and suppresses charge recombination. The results challenge the previous understanding of MAPbBr3-based photocatalysts and demonstrate a novel approach for developing highly active organic and inorganic perovskite photocatalysts. The successful application of the MA/BWO heterojunction in photocatalytic CO2 reduction expands the scope of organic and inorganic perovskites in the field of renewable energy conversion. By providing a broader perspective, our findings contribute to the ongoing efforts towards sustainable energy solutions, appealing

Staszczak M., Urbański L., Cristea M., Ionita D., Pieczyska E.A., Investigation of Shape Memory Polyurethane Properties in Cold Programming Process Towards Its Applications, Polymers, ISSN: 2073-4360, DOI: 10.3390/polym16020219, Vol.16, No.2, pp.219-1-219-20, 2024

Abstract:
Thermoresponsive shape memory polymers (SMPs) with the remarkable ability to remember a temporary shape and recover their original one using temperature have been gaining more and more attention in a wide range of applications. Traditionally, SMPs are investigated using a method named often “hot-programming”, since they are heated above their glass transition temperature (Tg) and after that, reshaped and cooled below Tg to achieve and fix the desired configuration. Upon reheating, these materials return to their original shape. However, the heating of SMPs above their Tg during a thermomechanical cycle to trigger a change in their shape creates a temperature gradient within the material structure and causes significant thermal expansion of the polymer sample resulting in a reduction in its shape recovery property. These phenomena, in turn, limit the application fields of SMPs, in which fast actuation, dimensional stability and low thermal expansion coefficient are crucial. This paper aims at a comprehensive experimental investigation of thermoplastic polyurethane shape memory polymer (PU-SMP) using the cold programming approach, in which the deformation of the SMP into the programmed shape is conducted at temperatures below Tg. The PU-SMP glass transition temperature equals approximately 65 ◦C. Structural, mechanical and thermomechanical characterization was performed, and the results on the identification of functional properties of PU-SMPs in quite a large strain range beyond yield limit were obtained. The average shape fixity ratio of the PU-SMP at room temperature programming was found to be approximately 90%, while the average shape fixity ratio at 45 ◦C (Tg − 20 ◦C) was approximately 97%. Whereas, the average shape recovery ratio was 93% at room temperature programming and it was equal to approximately 90% at 45 ◦C. However, the results obtained using the traditional method, the so-called hot programming at 65 ◦C, indicate a higher shape fixity value of 98%, but a lower shape recovery of 90%. Thus, the obtained results confirmed good shape memory properties of the PU-SMPs at a large strain range at various temperatures. Furthermore, the experiments conducted at both temperatures below Tg demonstrated that cold programming can be successfully applied to PU-SMPs with a relatively high Tg. Knowledge of the PU-SMP shape memory and shape fixity properties, estimated without risk of material degradation, caused by heating above Tg, makes them attractive for various applications, e.g., in electronic components, aircraft or aerospace structures.

Keywords:
polyurethane shape memory polymer, cold programming, thermal expansion, shape fixity, shape recovery

Zaszczyńska A., Kołbuk-Konieczny D., Gradys A. D., Sajkiewicz P. Ł., Development of Poly(methyl methacrylate)/nano-hydroxyapatite (PMMA/nHA) Nanofibers for Tissue Engineering Regeneration Using an Electrospinning Technique, Polymers, ISSN: 2073-4360, DOI: 10.3390/polym16040531, Vol.16, No.4, pp.531-1-19, 2024

Abstract:
The study explores the in vitro biocompatibility and osteoconductivity of poly(methyl methacrylate)/nano-hydroxyapatite (PMMA/nHA) composite nanofibrous scaffolds for bone tissue engineering (BTE). Electrospun scaffolds, exhibiting both low and high fiber orientation, were investigated. The inclusion of hydroxyapatite nanoparticles enhances the osteoconductivity of the scaffolds while maintaining the ease of fabrication through electrospinning. SEM analysis confirms the high-quality morphology of the scaffolds, with successful incorporation of nHA evidenced by SEM-EDS and FTIR methods. DSC analysis indicates that nHA addition increases the PMMA glass transition temperature (Tg) and reduces stress relaxation during electrospinning. Furthermore, higher fiber orientation affects PMMA Tg and stress relaxation differently. Biological studies demonstrate the composite material’s non-toxicity, excellent osteoblast viability, attachment, spreading, and proliferation. Overall, PMMA/nHA composite scaffolds show promise for BTE applications.

Keywords:
biomaterials, nanofibrous scaffolds, bone tissue engineering

Rudnicka Z., Pręgowska A., Glądys K., Perkins M., Proniewska K., Advancements in artificial intelligence-driven techniques for interventional cardiology, Cardiology Journal, ISSN: 1897-5593, DOI: 10.5603/cj.98650, pp.1-31, 2024

Abstract:
This paper aims to thoroughly discuss the impact of artificial intelligence (AI) on clinical practice in interventional cardiology (IC) with special recognition of its most recent advancements. Thus, recent years have been exceptionally abundant in advancements in computational tools, including the development of AI. The application of AI development is currently in its early stages, nevertheless new technologies have proven to be a promising concept, particularly considering IC showing great impact on patient safety, risk stratification and outcomes during the whole therapeutic process. The primary goal is to achieve the integration of multiple cardiac imaging modalities, establish online decision support systems and platforms based on augmented and/or virtual realities, and finally to create automatic medical systems, providing electronic health data on patients. In a simplified way, two main areas of AI utilization in IC may be distinguished, namely, virtual and physical. Consequently, numerous studies have provided data regarding AI utilization in terms of automated interpretation and analysis from various cardiac modalities, including electrocardiogram, echocardiography, angiography, cardiac magnetic resonance imaging, and computed tomography as well as data collected during robotic-assisted percutaneous coronary intervention procedures. Thus, this paper aims to thoroughly discuss the impact of AI on clinical practice in IC with special recognition of its most recent advancements.

Keywords:
artificial intelligence (AI), interventional cardiology (IC), cardiac modalities, augmented and/or virtual realities, automatic medical systems

Rudnicka Z., Szczepański J., Pręgowska A., Artificial Intelligence-Based Algorithms in Medical Image Scan Segmentation and Intelligent Visual Content Generation—A Concise Overview, Electronics , ISSN: 2079-9292, DOI: 10.3390/electronics13040746, Vol.13, No.4, pp.1-35, 2024

Abstract:
Recently, artificial intelligence (AI)-based algorithms have revolutionized the medical image segmentation processes. Thus, the precise segmentation of organs and their lesions may contribute to an efficient diagnostics process and a more effective selection of targeted therapies, as well as increasing the effectiveness of the training process. In this context, AI may contribute to the automatization of the image scan segmentation process and increase the quality of the resulting 3D objects, which may lead to the generation of more realistic virtual objects. In this paper, we focus on the AI-based solutions applied in medical image scan segmentation and intelligent visual content generation, i.e., computer-generated three-dimensional (3D) images in the context of extended reality (XR). We consider different types of neural networks used with a special emphasis on the learning rules applied, taking into account algorithm accuracy and performance, as well as open data availability. This paper attempts to summarize the current development of AI-based segmentation methods in medical imaging and intelligent visual content generation that are applied in XR. It concludes with possible developments and open challenges in AI applications in extended reality-based solutions. Finally, future lines of research and development directions of artificial intelligence applications, both in medical image segmentation and extended reality-based medical solutions, are discussed.

Keywords:
artificial intelligence, extended reality, medical image scan segmentation

Rudnicka Z., Proniewska K., Perkins M., Pręgowska A., Cardiac Healthcare Digital Twins Supported by Artificial Intelligence-Based Algorithms and Extended Reality—A Systematic Review , Electronics , ISSN: 2079-9292, DOI: 10.3390/electronics13050866, Vol.13, No.5, pp.1-35, 2024

Abstract:
Recently, significant efforts have been made to create Health Digital Twins (HDTs), Digital Twins for clinical applications. Heart modeling is one of the fastest-growing fields, which favors the effective application of HDTs. The clinical application of HDTs will be increasingly widespread in the future of healthcare services and has huge potential to form part of mainstream medicine. However, it requires the development of both models and algorithms for the analysis of medical data, and advances in Artificial Intelligence (AI)-based algorithms have already revolutionized image segmentation processes. Precise segmentation of lesions may contribute to an efficient diagnostics process and a more effective selection of targeted therapy. In this systematic review, a brief overview of recent achievements in HDT technologies in the field of cardiology, including interventional cardiology, was conducted. HDTs were studied taking into account the application of Extended Reality (XR) and AI, as well as data security, technical risks, and ethics-related issues. Special emphasis was put on automatic segmentation issues. In this study, 253 literature sources were taken into account. It appears that improvements in data processing will focus on automatic segmentation of medical imaging in addition to three-dimensional (3D) pictures to reconstruct the anatomy of the heart and torso that can be displayed in XR-based devices. This will contribute to the development of effective heart diagnostics. The combination of AI, XR, and an HDT-based solution will help to avoid technical errors and serve as a universal methodology in the development of personalized cardiology. Additionally, we describe potential applications, limitations, and further research directions.

Keywords:
Artificial Intelligence,Machine Learning,Metaverse,Virtual Reality,Extended Reality,Augmented Reality,Digital Twin,Health Digital Twin,personalized medicine,cardiology

Miller M., Scalici M., Fellous-Asiani M., Streltsov A., Power of noisy quantum states and the advantage of resource dilution, Physical Review A, ISSN: 2469-9926, DOI: 10.1103/PhysRevA.109.022404, Vol.109, pp.022404-1-022404-13, 2024

Abstract:
Entanglement distillation allows to convert noisy quantum states into singlets, which can, in turn, be used for various quantum technological tasks, such as quantum teleportation and quantum key distribution. Entanglement dilution is the inverse process: singlets are converted into quantum states with less entanglement. While the usefulness of distillation is apparent, practical applications of entanglement dilution are less obvious. Here, we show that entanglement dilution can increase the resilience of shared quantum states to local noise. The increased resilience is observed even if diluting singlets into states with arbitrarily little entanglement. We extend our analysis to other quantum resource theories, such as quantum coherence, quantum thermodynamics, and purity. For these resource theories, we demonstrate that diluting pure quantum states into noisy ones can be advantageous for protecting the system from noise. Our results demonstrate the usefulness of quantum resource dilution, and provide a rare example for an advantage of noisy quantum states over pure states in quantum information processing.

Paprocki B., Pręgowska A., Szczepański J., Does Adding of Neurons to the Network Layer Lead to Increased Transmission Efficiency?, IEEE Access, ISSN: 2169-3536, DOI: 10.1109/ACCESS.2024.3379324, Vol.12, pp. 42701-42709, 2024

Abstract:
The aim of this study is to contribute to the important question in Neuroscience of whether the number of neurons in a given layer of a network affects transmission efficiency. Mutual Information, as defined by Shannon, between the input and output signals for certain classes of networks is analyzed theoretically and numerically. A Levy-Baxter probabilistic neural model is applied. This model includes all important qualitative mechanisms involved in the transmission process in the brain. We derived analytical formulas for the Mutual Information of input signals coming from Information Sources as Bernoulli processes. These formulas depend on the parameters of the Information Source, neurons and network. Numerical simulations were performed using these equations. It turned out, that the Mutual Information starting from a certain value increased very slowly with the number of neurons being added. The increase is of the rate m_{−c} where m is the number of neurons in the transmission layer, and c is very small. The calculations also show that for a practical number (up to 15000) of neurons, the Mutual Information reaches only approximately half of the information that is carried out by the input signal. The influence of noise on the transmission efficiency depending on the number of neurons was also analyzed. It turned out that the noise level at which transmission is optimal increases significantly with this number. Our results indicate that a large number of neurons in the network does not mean an essential improvement in transmission efficiency, but can contribute to reliability.

Keywords:
Shannon communication theory,neural network,network layer,transmission efficiency,mutual information,model of neuron,spike trains,information source,entropy

Makowska K., Szymczak T., Kowalewski Z.L., Fatigue Behaviour of Medium Carbon Steel Assessed by the Barkhausen Noise Method, ACTA MECHANICA ET AUTOMATICA, ISSN: 1898-4088, DOI: 10.2478/ama-2024-0005, Vol.18, No.1, pp.40-47, 2024

Abstract:
In this paper, an attempt to estimate the stage of the fatigue process using the Barkhausen noise method is studied. First, microstructural and static tensile tests were carried out and, subsequently, fatigue tests up to failure were conducted. After determination of the material behaviour in the assumed static and dynamic conditions, the interrupted fatigue tests were performed. Each specimen was stressed up to a different number of cycles corresponding to 10%, 30%, 50%, 70% and 90% of fatigue lifetime for the loading conditions considered. In the next step of the experimental programme, the specimens were subjected to the Barkhausen magnetic noise measurements. Various magnetic parameters coming from the rms Barkhausen noise envelopes were determined. The linear relationship betweenthe full-width at half-maximum (FWHM) of the Barkhausen noise envelope and the number of loading cycles to fracture was found. Specimens loaded up to a certain number of cycles were also subjected to a tensile test to assess an influence of fatigue on the fracture features

Keywords:
fatigue, Barkhausen noise, structural steel, fracture, mechanical properties, deformation

Mackiewicz S., Ranachowski Z., Katz T., Dębowski T., Starzyński G., Ranachowski P., Modeling of Acoustic Coupling of Ultrasonic Probes for High-Speed Rail Track Inspection, ARCHIVES OF ACOUSTICS, ISSN: 0137-5075, DOI: 10.24425/aoa.2024.148787, pp.1-12, 2024

Abstract:
The paper presents the modeling of transmission of the ultrasonic plane wave through an uniform liquid layer. The considered sources of the ultrasonic wave were normal (straight) beam longitudinal wave probes and angle beam sheer waves probes commonly used in non-destructive testing. Coupling losses (CL) introduced by the presence of the coupling layer are discussed and determined applying the numerical procedure. The modeling applies to both monochromatic waves and short ultrasonic pulses with a specified frequency bandwidth. Model implementation and validation was performed using a specialized software. The predictions of the model were confirmed by coupling losses measurements for a normal beam longitudinal wave probe with a delay line made of polymethyl methacrylate (PMMA). The developed model can be useful in designing ultrasonic probes for high-speed rail track inspections, especially for establishing the optimal thickness of the water coupling layer and estimation of coupling losses, due to inevitable changes of the water gap during mobile rail inspection.

Keywords:
non-destructive testing, ultrasonic examination, plane wave propagation

Tabin J., Brodecki A., Parametrisation of Uniform Deformation in Ductile Metals Using Digital Image Correlation Technology, EXPERIMENTAL TECHNIQUES, ISSN: 0732-8818, DOI: 10.1007/s40799-024-00704-1, pp.1-12, 2024

Abstract:
This paper presents a novel measurement method that aims to qualitatively and quantitatively assess uniform deformation during displacement- and force-controlled tensile tests of ductile metals. The method utilizes digital image correlation technology to record the strain distribution during tensile testing, followed by the calculation of the floating root mean square (RMS) value of the strain amplitude along the specimen axis. By implementing this approach, the RMS-based profiles of strain amplitude are identified in different metals and alloys, including austenitic stainless steels, structural steel, copper, and aluminium alloys. Moreover, the proposed method holds potential for predicting important deformation characteristics such as distribution of intensive plastic zones, necking effect, and delocalization effect. Thus, it establishes a link between macroscale and microscale during the analysis of plastic deformation behaviour. The effectiveness of the new method is compared with existing strain and strain-rate methods. The novel approach demonstrates promising advantages in the context of the identification of metal-forming parameters.

Keywords:
Digital image correlation, Root mean square, Uniform strain distribution, Strain delocalization, Necking effect

Nazish J., Sohail M., Mahmood A., Shah Syed A., Qalawlus Aya Hamid M., Khaliq T., Nanocrystals loaded collagen/alginate-based injectable hydrogels: A promising biomaterial for bioavailability improvement of hydrophobic drugs, Journal of Drug Delivery Science and Technology, ISSN: 1773-2247, DOI: 10.1016/j.jddst.2023.105291, Vol.91, pp.105291-1-16, 2024

Abstract:
The study aims to improve the solubility of poorly soluble drug by developing an optimized formulation of nanocrystals and extend its release profile by incorporating optimized nanocrystals in a biopolymer based injectable hydrogel. Nanocrystals of Silymarin (SM) were developed by anti-solvent precipitation technique followed by homogenization. Various stabilizers were investigated and combination of polyvinyl pyrrolidine K30 (PVP K30) and sodium lauryl sulfate (SLS) in a specific ratio was chosen as a stabilizer for nanocrystals. The optimized nanocrystals possessed mean particle size 172 ± 5.23 nm and PDI of 0.228 ± 0.02. Sodium alginate (Alg) and collagen (Col) based injectable hydrogel in combination with pluronic F127 showed good biocompatibility, mechanical strength and biodegradability. The developed formulation was characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infra-red spectroscopy (FT-IR) and X-ray diffraction (XRD) analysis. The results of FT-IR and TGA showed structural cross-linking between polymers and promising thermal stability of formulation with increasing temperature, respectively. The nanocrystals loaded Alg-Col-F127 injectable hydrogel was degraded completely in 48 h. The results of in vitro release studies and in vivo pharmacokinetic profiling of silymarin nanocrystals laden Alg-Col-F127 injectable hydrogel exhibited controlled release behavior as compared to coarse silymarin suspension and silymarin nanocrystals. Therefore, nanosuspension integrated biopolymer-based hybrid injectable hydrogel system may be used to assist solubility and bioavailability enhancement as well as serve as platform to provide controlled drug release.

Keywords:
Nanocrystals, Injectable hydrogel, Hydrophobic drug, Solubility, Bioavailability

Zabojszcza P., Radoń U., Tauzowski P., Robust Optimization of the Steel Single Story Frame, Acta Polytechnica Hungarica, ISSN: 1785-8860, DOI: 10.12700/APH.21.1.2024.1.2, Vol.21, No.1, pp.9-29, 2024

Abstract:
In contemporary design practices, building structures are expected to not only meet safety requirements but also be optimized. However, optimal designs can be highly sensitive to random variations in model parameters and external actions. Solutions that appear effective under nominal conditions may prove inadequate when parameter randomness is considered. To address this challenge, the concept of robust optimization has been introduced, which extends deterministic optimization formulations to incorporate the random variability of parameter values. In this study, we demonstrate the applicability of robust optimization in the design of building structures using a simple orthogonal frame as an example. The static-strength analysis is conducted based on the displacement method, utilizing second-order theory. To assess the safety level of the steel frame, a preliminary evaluation is performed by determining the reliability index and failure probability using the Monte Carlo Method. Robust optimization is then employed, leveraging the second-order response surface. Experimental designs are generated following an optimal Latin hypercube plan. The proposal of a mathematical-numerical algorithm for solving the optimization problem while considering the random nature of design parameters constitutes the innovative aspect of this research.

Keywords:
reliability, robust optimization, second order theory, displacement method

Refilwe M., Nwaji N., Muthumuni M., Zhi-Long C., Tebello N., Photodynamic therapy characteristics of phthalocyanines in the presence of boron doped detonation nanodiamonds: Effect of symmetry and charge, Phothodygnosis, ISSN: 1873-1597, DOI: 10.1016/j.pdpdt.2021.102705, Vol.37, pp.Photodygnosis and photodynamic therapy-102705, 2024

Abstract:
he synthesis, photophysicochemical and photodynamic therapy (PDT) activities of benzothiazole substituted zinc phthalocyanine (Pc): 1 (asymmetrically substituted and composed of no charges), 2 (asymmetrically substituted and composed of three positive charges), and 3 (symmetrically substituted and composed of four positive charges), are presented. The triplet and singlet oxygen quantum yields were highest for complex 2 showing the importance of asymmetry and charge. The complexes are covalently and non-covalently linked to B doped detonation nanodiamonds (B@DNDs) to yield nanohybrids (B@DNDs-1, B@DNDs-2, B@DNDs-3). The presence of B@DNDs, asymmetry and positive charge resulted in improved PDT with the lowest cell viability being observed for B@DNDs-2 at 5%. The cell viability ranged from 5% to 7% for the nanohybrids compared to 19–26% for Pcs alone.

Cofas Vargas L.F.^♦, Azevedo Rodrigo M., Poblete S., Chwastyk M., Poma Bernaola A.M.^♦, The GōMartini Approach: Revisiting the Concept of Contact Maps and the Modelling of Protein Complexes, ACTA PHYSICA POLONICA A, ISSN: 0587-4246, DOI: 10.12693/APhysPolA.145.S9, Vol.145, No.3, pp.S9-S20, 2024

Abstract:
We present a review of a series of contact maps for the determination of native interactions in proteins and nucleic acids based on a distance threshold. Such contact maps are mostly based on physical and chemical construction, and yet they are sensitive to some parameters (e.g., distances or atomic radii) and can neglect some key interactions. Furthermore, we also comment on a new class of contact maps that only requires geometric arguments. The contact map is a necessary ingredient to build a robust Gō-Martini model for proteins and their complexes in the Martini 3 force field. We present the extension of a popular structure-based Gō--like approach to the study of protein–sugar complexes, and the limitations of this approach are also discussed. The Gō-Martini approach was first introduced by Poma et al. (J. Chem. Theory Comput. 13, 1366 (2017)) in Martini 2 force field, and recently, it has gained the status of gold standard for protein simulation undergoing conformational changes in Martini 3 force field. We discuss several studies that have provided support for this approach in the context of the biophysical community.

Keywords:
Martini 3,Structure-based coarse-graining,SMFS,biomolecules,GoMartini

Mousavisogolitappeh H., Amini C., Efficient homogenization of honeycomb sandwich panels using orthotropic core simplification and Finite Element-based method: A comparative study, Journal of Composite Materials, ISSN: 0021-9983, DOI: 10.1177/002199832412404, pp.1-13, 2024

Abstract:
Composite materials, particularly honeycomb composites, are widely utilized in various industries, including aerospace, due to their high energy absorption against the impact and exceptional strength-to-weight ratio. This study aims to leverage the plastic and elastic properties of these materials to develop a simplified numerical model that incorporates orthotropic properties for core modeling. By doing so, the need for detailed honeycomb structure modeling is eliminated, resulting in reduced computational costs and time. A comprehensive three-dimensional finite element model, accounting for structural intricacies, is presented based on experimental data from a reputable source (isotropic model) and its equivalent finite element model (orthotropic model). The model is validated by the experimental results, demonstrating good agreement. The study also investigates parameters such as energy absorption, the internal energy of the core and faces, maximum displacement, and maximum contact force under low-velocity impact scenarios with spherical and cylindrical projectiles. These findings highlight the effectiveness of the orthotropic model, particularly in showcasing greater energy absorption in the core of the sandwich panel when subjected to a cylindrical impactor.

Keywords:
honeycomb, sandwich panel, homogenization, finite element analysis, impact

Osial M., Ha G., Vu V., Nguyen P., Nieciecka D., Pietrzyk‑Thel P., Urbanek O., Olusegun S., Wilczewski S.^♦, Giersig M., Do H., Dinh T., One-pot synthesis of magnetic hydroxyapatite (SPION/HAp) for 5-fluorouracil delivery and magnetic hyperthermia, Journal of Nanoparticle Research, ISSN: 1388-0764, DOI: 10.1007/s11051-023-05916-x, Vol.26, No.7, pp.1-23, 2024

Abstract:
This work presents the synthesis and characterization of a composite made of superparamagnetic iron oxide and hydroxyapatite nanoparticles (SPION/HAp) with a well-developed surface for loading anticancer drugs and for use in magnetic hyperthermia and local chemotherapy. The proposed material was obtained by an easy one-pot co-precipitation method with a controlled ratio of SPION to HAp. The morphology was studied by SEM and TEM, indicating rod-like structures for high HAp content in the composite and granule-like structures with increasing SPION. Its crystallinity, elemental composition, and functional groups were determined by X-ray diffraction, EDS, and FT-IR, respectively. The nanocomposite was then stabilized with citrates (CA), polyethylene glycol (PEG), and folic acid (FA) as agents to improve intracellular absorption, while turbidimetric studies confirmed that only citrates effectively stabilized the magnetic carriers to form a colloidal suspension. Subsequently, 5-fluorouracil (5-FU) was loaded into the magnetic carriers and tested in vitro using the L-929 cell line. The studies showed no cytotoxicity of the citrate-stabilized suspension against fibroblasts and some cytotoxicity after 5-FU release. In addition to in vitro studies, the composite was also tested on biomimetic membranes made of DOPC, DOPE, cholesterol, and DOPS lipids using Langmuir trough. The results show that the resulting suspension interacts with biomimetic membranes, while magnetic hyperthermia studies confirm effective heat generation to achieve therapeutic 42–46 °C and improve drug release from magnetic carriers.

Keywords:
SPION, Hydroxyapatite, Magnetic hyperthermia, Drug delivery, 5-fluorouracil, Biomimetic membranes, Nanostructures, Cancer treatment

Jain A., Michalska M., Enhanced electrochemical properties of multiwalled carbon nanotubes modified with silver nanoparticles for energy storage application, MATERIALS CHEMISTRY AND PHYSICS, ISSN: 0254-0584, DOI: 10.1016/j.matchemphys.2024.129200, Vol.317, No.129200, pp.1-9, 2024

Abstract:
This work reports an easy, straightforward, and cost-effective method to synthesize a composite material using multiwalled carbon nanotubes (MWCNTs) and silver nanoparticles (Ag NPs) for application as an electrode in supercapacitors. The objective of this work was to enhance the charge transfer mechanism in supercapacitor cells by introducing the conductive particles in the MWCNT framework. The pivotal studies, like scanning (SEM), and transmission (TEM) electron microscopy, X-ray diffraction (XRD), Raman, and X-ray photoelectron (XPS) spectroscopy confirmed the formation of the composite as well as a successful deposition of Ag NPs on MWCNT. The surface area of the composite was evaluated by using the N2 adsorption-desorption studies and it was found to be of the order of 358 m2 g−1. Electrochemical studies were performed using a two-electrode system. Magnesium ion-based polymer gel electrolyte was used as an electrolyte material. The single electrode-specific capacitance was observed to be ∼31.9 F g−1 with power density and energy density values of ∼4.4 kW kg−1 and 1.2 Wh kg−1, respectively, at a current density of 0.46 A g−1. The cell was stable up to ∼5000 charge-discharge cycles with ∼96% of capacitance retention at the end of 5000 cycles.

Keywords:
Supercapacitor, Gel polymer electrolyte, MWCNTs

Grigoryan N., Chudziński P., Role of electron-electron interactions in electron emission from nanotube materials, PHYSICAL REVIEW MATERIALS, ISSN: 2475-9953, DOI: 10.1103/PhysRevMaterials.8.016003, Vol.8, pp.1-16, 2024

Abstract:
Nanotubes and nanorods have been recently established as very good materials to work as electron sources in a field emission (FE) process. These are one-dimensional materials and electron-electron interactions are expected to play a crucial role in their physics. Here we study the influence of electron-electron interactions on the field emission. We study the problem in the low energy regime; thus we need to abandon the antiadiabatic approximation and derive tunneling amplitude for a finite duration of the tunneling process. In this work we identified the parameters when exact analytic expression for tunneling current can be given. We obtained formalism that enables one to capture at the same time the collective effects due to electron-electron interactions and thermionic emission. Our results reveal that different types of nanotubes, and their minigap/compressibility parameters, can be easily distinguished based on FE measurements on these materials.

Drożyner P., Brodecki A., Szymczak T., Stand testing of springs for drum brake systems, DIAGNOSTYKA, ISSN: 1641-6414, DOI: 10.29354/diag/177242, Vol.24, No.4, pp.1-6, 2024

Abstract:
The paper concerns the study of changes in responses of spring for drum brake systems, due to fatigue cycles conducted at operational regimes of vehicles with respect to the number of kilometers. Three types of springs from two manufacturers were examined i.e. double cylindrical, single cylindrical, and conical helical. The springs were subjected to a durability test up to 1×106 loading cycles, covering 300-500 thousand kilometers traveled. Tensile test was used for collecting differences between results for the tested object in the as-receive state and after fatigue. Values of the Pearson correlation coefficient were used to indicate differences between tested objects before and after loading cycles. They show that the obtained results expressed a very strong correlation, which means that the elastic response of the springs during operation over a distance of 300-500 thousand kilometers did not change significantly. Taking into account the recommendations of brake system manufacturers regarding the replacement of brake drums after 150,000 and 50,000 kilometers, respectively, it can be concluded that brake springs are the most durable and reliable element of such a brake system.

Keywords:
drums, springs, fatigue, reliability

Olusegun S., Souza Guilhermina de O., Sutuła S., Osial M., Krajewski M.^♦, Pękała M., Sobczak K., Felis E., Krysiński P., Methotrexate anti-cancer drug removal using Gd-doped Fe3O4: Adsorption mechanism, thermal desorption and reusability, Groundwater for Sustainable Development, ISSN: 2352-801X, DOI: 10.1016/j.gsd.2024.101103, Vol.25, pp.1-9, 2024

Keywords:
Adsorption,Thermal desorption,Gd-doped Fe3O4,Methotrexate

Ray A., Thu Thi Minh T., Santos Natividade Rita d., Azevedo Rodrigo M., Joshua S., Danahe M., Koehler M., Simon P., Qingrong Z., Fabrice B., Laurent G., Poma Bernaola A.M., Alsteens D., Single-Molecule Investigation of the Binding Interface Stability of SARS-CoV-2 Variants with ACE2, ACS Nanoscience Au, ISSN: 2694-2496, DOI: 10.1021/acsnanoscienceau.3c00060, pp.1-10, 2024

Abstract:
The SARS-CoV-2 pandemic spurred numerous research endeavors to comprehend the virus and mitigate its global severity. Understanding the binding interface between the virus and human receptors is pivotal to these efforts and paramount to curbing infection and transmission. Here we employ atomic force microscopy and steered molecular dynamics simulation to explore SARS-CoV-2 receptor binding domain (RBD) variants and angiotensin-converting enzyme 2 (ACE2), examining the impact of mutations at key residues upon binding affinity. Our results show that the Omicron and Delta variants possess strengthened binding affinity in comparison to the Mu variant. Further, using sera from individuals either vaccinated or with acquired immunity following Delta strain infection, we assess the impact of immunity upon variant RBD/ACE2 complex formation. Single-molecule force spectroscopy analysis suggests that vaccination before infection may provide stronger protection across variants. These results underscore the need to monitor antigenic changes in order to continue developing innovative and effective SARS-CoV-2 abrogation strategies.

Keywords:
SARS-Cov-2,Molecular Dynamics ,Immunity,SMFS,Nanomechanics,Free Energy,Jarzynski,Receptor,Protein complex,interfaces

Ziai Y., Lanzi M., Rinoldi C., Zargarian Seyed S., Zakrzewska A., Kosik-Kozioł A., Nakielski P., Pierini F., Developing strategies to optimize the anchorage between electrospun nanofibers and hydrogels for multi-layered plasmonic biomaterials, Nanoscale Advances, ISSN: 2516-0230, DOI: 10.1039/d3na01022h, pp.1-13, 2024

Abstract:
Polycaprolactone (PCL), a recognized biopolymer, has emerged as a prominent choice for diverse biomedical endeavors due to its good mechanical properties, exceptional biocompatibility, and tunable properties. These attributes render PCL a suitable alternative biomaterial to use in biofabrication, especially the electrospinning technique, facilitating the production of nanofibers with varied dimensions and functionalities. However, the inherent hydrophobicity of PCL nanofibers can pose limitations. Conversely, acrylamide-based hydrogels, characterized by their interconnected porosity, significant water retention, and responsive behavior, present an ideal matrix for numerous biomedical applications. By merging these two materials, one can harness their collective strengths while potentially mitigating individual limitations. A robust interface and effective anchorage during the composite fabrication are pivotal for the optimal performance of the nanoplatforms. Nanoplatforms are subject to varying degrees of tension and physical alterations depending on their specific applications. This is particularly pertinent in the case of layered nanostructures, which require careful consideration to maintain structural stability and functional integrity in their intended applications. In this study, we delve into the influence of the fiber dimensions, orientation and surface modifications of the nanofibrous layer and the hydrogel layer's crosslinking density on their intralayer interface to determine the optimal approach. Comprehensive mechanical pull-out tests offer insights into the interfacial adhesion and anchorage between the layers. Notably, plasma treatment of the hydrophobic nanofibers and the stiffness of the hydrogel layer significantly enhance the mechanical effort required for fiber extraction from the hydrogels, indicating improved anchorage. Furthermore, biocompatibility assessments confirm the potential biomedical applications of the proposed nanoplatforms.

Pulov V., Kowalczuk W., Mladenov I.M., Geometry of Enumerable Class of Surfaces Associated with Mylar Balloons, Mathematics, ISSN: 2227-7390, DOI: 10.3390/math12040557, Vol.12, No.4, pp.557-1-18, 2024

Abstract:
In this paper, the very fundamental geometrical characteristics of the Mylar balloon like the profile curve, height, volume, arclength, surface area, crimping factor, etc. are recognized as geometrical moments ℐ

Keywords:
Mylar balloons, geometrical moments, elliptic integrals, beta and gamma functions, recursive relations, crimping factor, lemniscate constant