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The co-sintering behavior of a ceramic-metal bilayer is carefully investigated. This bilayer is composed of a gold film deposited by screen-printing on a silica-based low-temperature cofired ceramic (LTCC) layer. First, behaviors of both materials in free sintering are finely characterized. LTCC exhibits a viscous flow sintering mechanism, whereas the densification mechanism of gold is controlled by grain boundary diffusion (with an identified apparent activation energy of 101 ± 15 kJ mol−1). Free sintering of gold is also marked by a two-step densification process due to its large bimodal particle size distribution. A methodology is proposed to estimate gold viscosity at high temperatures directly from raw experimental data in free sintering, without performing dedicated mechanical characterizations. Based on the constitutive laws identified for LTCC and gold materials, analytical and numerical models of the bilayer co-sintering process are built. During co-sintering, stresses generated by densification kinetic mismatch between gold and LTCC are progressively relaxed by camber phenomenon. Calculated evolutions of camber in co-sintering are compared to curvature monitoring by ombroscopy. Finite element simulation in 3D fits well with the experimental data, whereas the analytical solution strongly underestimates camber rates. This shows that the simplified numerical approach suggested here leads to a robust numerical model, faithfully describing thermomechanical interactions occurring in co-sintering within the ceramic-metal bilayer. [ABSTRACT FROM AUTHOR]

The increasing need for sustainable energy and the transition from a linear to a circular economy pose great challenges to the materials science community. In this view, the chance of producing efficient nanocatalysts for water splitting using industrial waste as starting material is attractive. Here, we report low-cost processes to convert Mo-based industrial waste powder into efficient catalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). pH controlled hydrothermal processing of Mo-based industrial waste powder leads to pure orthorhombic MoO3 nanobelts (50–200 nm wide, 10 µm long) with promising OER performances at 10 mA·cm−2 with an overpotential of 324 mV and Tafel slope of 45 mV·dec−1 in alkaline electrolyte. Indeed, MoS2/MoO3 nanostructures were obtained after sulfurization during hydrothermal processes of the MoO3 nanobelts. HER tests in acidic environment show a promising overpotential of 208 mV at 10 mA·cm−2 and a Tafel slope of 94 mV·dec−1. OER and HER performances of nanocatalysts obtained from Mo industrial waste powder are comparable or better than Mo-based nanocatalysts obtained from pure commercial Mo reagent. This work shows the great potential of reusing industrial waste for energy applications, opening a promising road to join waste management and efficient and sustainable nanocatalysts for water splitting. [ABSTRACT FROM AUTHOR]

The rapid advancement of Internet of Things (IoT) technology and AI microchips has increased the demand for efficient and cost‐effective cooling solutions. However, traditional Bi2Te3‐based thermoelectric modules face the challenge of low abundance tellurium (Te). Although Te‐free modules using MgAgSb have been explored, they still suffer from a low price‐to‐performance ratio. To address these issues, this study investigates the development of alternative thermoelectric materials that are both cost‐effective and Te free. In this work, the potential of cost‐effective Te‐free alternatives is explored for thermoelectric applications by developing a high‐performance module composed of amorphous carbon‐modulated Mg3(Bi,Sb)2 and electron‐poor CdSb. The modules of CdSb/Bi2Te3 and CdSb/Mg3(Bi,Sb)2 demonstrate superior refrigeration performance, achieving a maximum temperature difference (ΔTmax) of 49.2 and 46 K, respectively. Notably, the material cost of CdSb/Mg3(Bi,Sb)2 module is only 5.5% of Te‐free modules built on MgAgSb, highlighting a significant economic advantage. This work provides a viable, ultralow‐cost approach to meet general refrigeration needs, thereby enhancing the practical value and application potential of thermoelectric materials. [ABSTRACT FROM AUTHOR]

Fractional differential viscoelastic models can describe complex material behaviours and fit experimental data well; however, the physical significance of model parameters is difficult to express. In this study, the fractional differential Maxwell, Kelvin, and Zener models were used to fit the short-term creep compliance curves of polymethyl methacrylate at different ageing times. The model fits were in good agreement with the experimental data. As the ageing time increased, the fractional differential Zener model showed a relative increase in the modulus parameter of the spring and a relative decrease in the modulus parameter reflecting the viscosity of the spring-pot, which indicated that physical ageing made the material more elastic. The relaxation time of the material increased, which indicated that the physical ageing reduced the free volume of the material, hindered the movement of molecules/segments, and increased the time required for the material to reach equilibrium. The fractional order of the model decreased, which reflected the phenomenon that physical ageing reduced the creep compliance of the material. Using the relaxation time as the time scale, the creep curves at different ageing times under the same stress level could be superimposed, naturally presenting the time–ageing time equivalence principle. [ABSTRACT FROM AUTHOR]

Bipolar membranes in electrochemical CO2 conversion cells enable different reaction environments in the CO2-reduction and O2-evolution compartments. Under ideal conditions, water-splitting in the bipolar membrane allows for platinum-group-metal-free anode materials and high CO2 utilizations. In practice, however, even minor unwanted ion crossover limits stability to short time periods. Here we report the vital role of managing ionic species to improve CO2 conversion efficiency while preventing acidification of the anodic compartment. Through transport modelling, we identify that an anion-exchange ionomer in the catalyst layer improves local bicarbonate availability and increasing the proton transference number in the bipolar membranes increases CO2 regeneration and limits K+ concentration in the cathode region. Through experiments, we show that a uniform local distribution of bicarbonate ions increases the accessibility of reverted CO2 to the catalyst surface, improving Faradaic efficiency and limiting current densities by twofold. Using these insights, we demonstrate a fully platinum-group-metal-free bipolar membrane electrode assembly CO2 conversion system exhibiting <1% CO2/cation crossover rates and 80-90% CO2-to-CO utilization efficiency over 150 h operation at 100 mA cm−2 without anolyte replenishment. Here, authors report that local ionic transport across cathode catalyst layers is vital in improving CO production from CO2. This work demonstrates the potential of a CO2 electrolyzer constructed from materials free from platinum group metals. [ABSTRACT FROM AUTHOR]

Background: In Switzerland, the scholastic aptitude test for medical-school selection takes place in three languages. This study examined the effects of two quasi-experimental interventions that aimed to reduce existing differences in test results between the French- and German-speaking language candidates. Methods: Between 2018 and 2023, the population of applicants to Swiss medical schools consisted of N = 18'824 German- and French-speaking individuals. Based on a quasi-experimental design, we examined the effects of two interventions regarding preparatory material, in these cohorts. The first intervention (2022) consisting of practice trials in baccalaureate schools in the canton of Fribourg enabled French-speaking candidates primarily from the canton of Fribourg to prepare more intensively with official tasks. Practice trials enable future candidates to complete a published test version under original conditions and thus prepare how to approach the real test. The second intervention (2023) released new preparatory material in all languages for one group of tasks for which differences between the language groups were more pronounced than in the other tasks. The test provider offered this material for free download together with existing preparation materials and thereby enabled more intensive preparation. Results: After the first intervention, the initially small to medium-sized mean differences in z-transformed test scores between French-speaking candidates from Fribourg and German-speaking candidates were nearly eliminated (from 0.39 to 0.05). Also for French-speaking candidates from outside of the canton of Fribourg, the mean differences were smaller than before the intervention (0.48 before, 0.39 after first intervention). After the second intervention, particularly the mean differences in test scores between German-speaking and French-speaking candidates from outside of Fribourg were further reduced (to 0.24). Conclusions: The two interventions regarding material for preparing to participate in the aptitude test affected candidates' test scores. They reduced the gap between German- and French-speaking candidates showing that the additional benefits of commercial offers for test preparation are limited. Hence, offering comparable official preparation material to all language groups enhances test fairness. [ABSTRACT FROM AUTHOR]

High-consequence pathogens such as the Ebola, Marburg, and Lassa viruses are handled in maximum-containment biosafety level 4 (BSL-4) laboratories. Genetic material is often isolated from such viruses and subsequently removed from BSL-4 laboratories for a multitude of downstream analyses using readily accessible technologies and equipment available at lower-biosafety level laboratories. However, it is essential to ensure that these materials are free of viable viruses before removal from BSL-4 laboratories to guarantee sample safety. This study details the in-house procedure used for validating the inactivation of Ebola, Marburg, and Lassa virus cultures after incubation with AVL lysis buffer (Qiagen) and ethanol. This study's findings show that no viable virus was detectable when high-titer cultures of Ebola, Marburg, and Lassa viruses were incubated with AVL lysis buffer for 10 min, followed by an equal volume of 95% ethanol for 3 min, using a method with a sensitivity of ≤0.8 log10 TCID50 as the limit of detection. [ABSTRACT FROM AUTHOR]

Objectives: address the lack of specialized courses in user interface (UI) design for mobile applications in Jordanian universities' visual communication design curriculum. Develop an experimental educational syllabus for teaching UI mobile application design to visual communication design students in Jordanian universities. Methods: Four parts were used to structure the research: an introduction, the UI process, case studies and best practices, and a final project. Introduction: Basics of UI and UX Design. UI Process: theory, practice, tools, and publishing. Case Studies and Best Practices: Focus on medical UI mobile app design, including a UI checklist tool. Final Project: Students use free materials to present their work and review their projects with the class. Results:. The newly developed syllabus addresses the educational needs in UI mobile app design for visual communication design students. It emphasizes the importance of involving experts and practitioners in the design process. The syllabus provides comprehensive coverage of UI/UX design, practical tools, case studies, and project-based learning. Conclusions: The developed syllabus fills a critical gap in the visual communication design curriculum of Jordanian universities. It enhances students' knowledge and skills in UI mobile app design, better preparing them for the demands of the industry. The involvement of experts and practitioners is essential in creating effective educational programs in rapidly developing fields like mobile app design. [ABSTRACT FROM AUTHOR]

Over a decade, single‐junction perovskite solar cells (PSCs) have achieved a remarkable power conversion efficiency of 26.4%. However, the pressing challenge remains to address their long‐term stability for large‐scale industrial production. A significant factor contributing to this instability is the use of doped hole‐transporting materials (HTMs), which often introduce moisture into contact with the perovskite film, leading to its degradation. To address this issue, research has focused on developing novel and stable "dopant‐free" HTMs. These materials possess inherent conductivity and can function without the need for additional dopants. These HTMs, constructed with donors and acceptors, have properties like film‐forming abilities, tunable molecular weights, unique stacking, and high hole mobility. Among the classic donor units, benzodithiophene (BDT) has emerged as a widely utilized component for the synthesis of molecules and polymers for photovoltaic applications. To stimulate further research and optimization of these materials, this overview presents a comprehensive examination of various BDT‐based dopant‐free polymeric HTMs with different acceptor units within the field of PSCs. It provides a concise historical overview, followed by an in‐depth classification and examination of polymeric structures. The exploration delves into their constituent building blocks, aiming to uncover the relationships between structure and activity wherever feasible. [ABSTRACT FROM AUTHOR]

Efficient utilization of wood is inseparable from high-quality drying, and analysis of its free shrinkage performance is essential to optimize the drying process. This study took Pinus sylvestris L. sawn timber (500 mm ×200 mm×50 mm) as the research object and adopted the image analysis method to analyze the influence rules of different temperatures and axial positions of the test material on the free dry shrinkage coefficient of each layer of specimens in the thickness direction. The free shrinkage coefficients of each layer in the thickness direction of the test material decreased from the maximum value of the first layer near the tangential direction (0.282%, 0.275%, 0.267%, at 60 ℃, 80 ℃, and 100 ℃, respectively) to the minimum value of the ninth layer near the radial direction (0.248%, 0.249%, 0.227%); except for the near-radial layers, when temperature increased from 60 ℃ to 100 ℃ the free shrinkage coefficients of other representative layers decreased with increased temperature. The first layer's free shrinkage coefficient decreased from 0.282% to 0.267%, and the fifth layer decreased from 0.264% to 0.243%. The difference of free shrinkage coefficients between corresponding layers at different axial positions of the test material was less than 0.017%, and the size stability of the corresponding layers at axial positions was high. [ABSTRACT FROM AUTHOR]

Extensive efforts have been devoted to investigate the distribution of dopants in ceramics. However, one critical question remained barely explored, which is the redistribution of dopants between amorphous and crystalline phases during fast sintering of ceramics. Here we address this gap by observing the redistribution of five selected dopants (Y, Ce, Yb, Hf, and Ta) in ZrO2–SiO2 nanoceramics during sintering. We designed two groups of experiments: In group one, dual‐phase amorphous particles were sintered with multicomponent crystalline ones. The former particles were ZrO2–SiO2 glass, whereas the latter ones consisted of ZrO2 solid‐solution nanocrystallites (SSNCs) embedded in an oxide glass containing Zr, Si, Y, Ce, Hf, Yb, and Ta. In group two, dual‐phase crystalline particles were sintered with multicomponent amorphous ones. The former particles were composed of ZrO2 nanocrystallites (NCs) embedded in an amorphous SiO2 matrix, whereas the latter ones were oxide glass containing Zr, Si, Y, Ce, Hf, Yb, and Ta. Redistribution of the dopants from the glass to ZrO2 NCs occurred in the two groups, that is, the five dopants migrated from the glass matrix into the ZrO2 NCs, forming ZrO2 SSNCs. The redistribution of the dopants not only increased the configuration entropy of the ZrO2 NCs but also benefited the network structure integrity of SiO2 glass. The dopant redistribution process was driven by the minimization of the studied material's free energy. The reported results are important for understanding the redistribution behaviors of dopants and are expected to provide new insights to design new ceramics via the multielement co‐doping strategy. [ABSTRACT FROM AUTHOR]

The burgeoning significance of antiferroelectric (AFE) materials, particularly as viable candidates for electrostatic energy storage capacitors in power electronics, has sparked substantial interest. Among these, lead-free sodium niobate ( N a N b O 3 ) AFE materials are emerging as eco-friendly and promising alternatives to lead-based materials, which pose risks to human health and the environment, attributed to their superior recoverable energy density and dielectric breakdown strength. This review offers an insightful overview of the fundamental principles underlying antiferroelectricity and the applications of AFE materials. It underscores the recent advancements in lead-free N a N b O 3 -based materials, focusing on their crystal structures, phase transitions, and innovative strategies devised to tailor their electrostatic energy storage performance. Finally, this review delineates the prevailing challenges and envisages future directions in the realm of N a N b O 3 -based electrostatic energy storage capacitors, with the goal of fostering further advancements in this pivotal field. [ABSTRACT FROM AUTHOR]

With the global market value of sensors on the rise, this paper focuses on the fabrication and testing of a proof-of-concept piezoelectric energy harvester which is able to harvest mechanical energy from the ambient environment and convert it into electrical energy in order to power wireless sensor networks. We focused on obtaining a new device structure based on a comb-type array of piezoelectric MEMS cantilevers (2 × 10) for a resonant frequency in the environmental application domain (a few hundred Hz) and a chip area of only 1 cm2. The configuration of the lead-free piezoelectric cantilever consists of a Si substrate, a pair of Ti-Pt electrodes and a sputtered piezoelectric layer of 12% Sc-doped AlN with a thickness of 1000 nm, a dielectric constant of ~13 and e31,f = 1.3 C/m2. At a resonant frequency of 465.2 Hz and an acceleration of 1 g, the maximum value for the collected power was 2.53 µW for an optimal load resistance of 1 MΩ resulting in a power density of 60.2 nW/mm3 for the unpacked device, without taking into account the vibration volume. By increasing the excitation acceleration to 2 g RMS and using LTC3588-1 for the power circuitry we were able to obtain a stabilized output voltage of 1.8 V. [ABSTRACT FROM AUTHOR]

Consume-less appeals in social marketing can help reduce the lavish consumption in wealthy countries, which poses a major threat to the climate. This study experimentally examines the effectiveness of three different types of consume-less appeals (informative, social normative, and emotional appeals) on participants' actual spending levels during a real shopping trip compared to a control group (no appeal). In addition, the study tests whether these appeals evoke negative rebounds (in terms of post-purchase climate donation) or positive rebounds (in terms of accepting post-purchase material giveaways). A field experiment in a grocery store in Germany with 170 participants shows that social normative and the emotional appeals reduce actual shopping spending. Informative and social normative appeals increase donations, and emotional appeals reduce the items of taken giveaways. The findings further support certain indirect impacts of the consume-less appeals on rebounds in terms of spending levels. [ABSTRACT FROM AUTHOR]

The study of shock-driven ejecta production has focused on Richtmyer–Meshkov instability (RMI) growth from geometric features of the material surface. Extensive study of this mechanism under both single- and multiple-shock conditions has found that the ejected mass tends to be closely associated with the shocked surface phase, and its temperature is not dramatically greater than the hydrodynamic shock temperature of the bulk. In this work, we propose and demonstrate a new ejecta production mechanism that can occur under multiple-shock conditions based on the collapse of bubbles near the free surface of the material. This mechanism produces ejected mass that is much greater in quantity than observed in the RMI case. The particles are much hotter than predicted by the shock Hugoniot state, and the ejected mass does not appear to be strongly dependent upon initial surface finish. The ejecta source extends into the material with no clear remaining free surface. We name this mechanism Shallow Bubble Collapse (SBC) and discuss the conditions under which it activates. We demonstrate resolved modeling methods that enable the calculation, design, and study of SBC as a mechanism and perform a series of experiments to compare with the models. Under some multiple-shock conditions, SBC ejection produces ten times more ejected mass than RMI growth. [ABSTRACT FROM AUTHOR]

The burgeoning significance of antiferroelectric (AFE) materials, particularly as viable candidates for electrostatic energy storage capacitors in power electronics, has sparked substantial interest. Among these, lead-free sodium niobate (NaNbO3) AFE materials are emerging as eco-friendly and promising alternatives to lead-based materials, which pose risks to human health and the environment, attributed to their superior recoverable energy density and dielectric breakdown strength. This review offers an insightful overview of the fundamental principles underlying antiferroelectricity and the applications of AFE materials. It underscores the recent advancements in lead-free NaNbO3-based materials, focusing on their crystal structures, phase transitions, and innovative strategies devised to tailor their electrostatic energy storage performance. Finally, this review delineates the prevailing challenges and envisages future directions in the realm of NaNbO3-based electrostatic energy storage capacitors, with the goal of fostering further advancements in this pivotal field.

In this work, a low-profile and flexible antenna operating in the ISM (2.4–2.4835) GHz band for bio-telemetry applications is presented. This antenna is designed on two flexible substrate materials: Roger RO3003 with a thickness of 0.254 mm and jeans fabric material with a thickness of 0.7 mm, of an overall foot print of 20 × 30 mm². The deformation bending of the designed antenna in two different cases is studied. The designed antenna is backed by a 3×3 artificial magnetic conductor (AMC) array structure, which resulted in the final design configuration. The antenna is backed by an AMC array structure to achieve a lower specific absorption rate (SAR) as well as high gain when it is mounted on biological tissue. For validation, the antenna is fabricated on two flexible substrate materials and then measured in free space as well as on four different parts of the realistic human (chest, back, arm, and leg) body with and without AMC structure. Furthermore, the SAR is measured on cSAR3D flat. Finally, for reliable communication, the link margin is calculated. [ABSTRACT FROM AUTHOR]

Heavy atom free organic materials absorbing in red to near infrared (NIR) region are potential candidates as photosensitizers (PS) in photodynamic therapy (PDT). PDT relies on many factors and one of them is singlet oxygen generation ability of PS in aqueous medium. In this contribution, we report the synthesis of a new PS i. e. 8‐thienyl bisbenzothieno‐[b]‐fused‐boron‐dipyrromethene (BT‐[b]‐fused BODIPY). This PS shows absorption (λabs) at ~650 nm in toluene while in its water‐dispersible nanoaggregates it is found at ~764 nm. Nanoaggregates of BT‐[b]‐fused BODIPY demonstrated dual advantages, (i) facilitating PS release in the cellular system and (ii) sharply enhanced singlet oxygen efficiency (ΦΔ ${\Phi _{\rm{\Delta }} }$ ~48 %) in aqueous medium. Intracellular reactive oxygen species (ROS) generation was confirmed by 2′,7′‐dichlorodihydrofluorescein diacetate (DCFDA) assay in A549 cells. In vitro photocytotoxic studies of BT‐[b]‐fused BODIPY are carried out in different carcinomas i. e. MCF‐7 and A549 cells. It has zero dark cell toxicity while half maximal inhibitory concentration (IC50) in MCF‐7 is found to be low (6.08±1.1) μM and 7.41±1.9 μM in A549 on 15 min light exposure. These nanoaggregates induce apoptosis in cancer cells on light irradiation thereby proving it to be a potential PS for PDT. [ABSTRACT FROM AUTHOR]

In this paper, a generalized formulation for vibration characteristics investigation of bi-dimensional functionally graded martial annular plates of variational thicknesses is built up using the dynamic stiffness method. The distributions of material attribute both in the radial direction and the thickness direction are in a power-law variation of the constituents' volume fraction. General solutions of the government equation of an annular plate are solved by a strong-formed algorithm, then the dynamic stiffness formulation is employed to present the vibration study of the bi-dimensional functionally graded annular plate. Various boundary constrains are considered in the modeling process. Results of present formulation are verified by comparison with existing literature and numerical examples. A systematic parametric study is performed to study the influences of boundary constrains, geometric parameters, and functional material distributions on the free vibration characteristic of the annular plate. Results shows that the natural frequency of radial functionally graded annular plate are the largest and the natural frequency of the bi-dimensional functionally graded annular plate are the minimum when the values of the power laws are both 1. When the power-law index is large, the change of frequency with the power-law index is more obvious. [ABSTRACT FROM AUTHOR]

The aim of the study is to determine the level of price that individuals living in Türkiye are willing to pay (WTP) for a hypothetical COVID-19 vaccine. In addition, the study also aims to identify the socioeconomic factors affecting that level of WTP. The data is collected via a virtually applied questionnaire. Probit estimations are employed to determine the level of price that is willing to be paid. Further, the socioeconomic factors affecting the revealed WTP level are identified with an ordered-probit estimation strategy. The average price level that the participants are willing to pay for two doses of a hypothetical COVID-19 vaccine which immunes for 12 months is ₺316.93 ($42.66). Higher education groups, public employees, married people, and urban individuals are more likely to pay at higher price levels of hypothetical COVID-19 vaccine. Interestingly, the individuals living with a pregnant woman or a baby, the ones who experienced severe COVID-19 disease and the ones who already decided to be vaccinated are more likely to pay at relatively low-price levels. This study may contribute to broader literature as it will provide evidence from Türkiye for international comparisons. [ABSTRACT FROM AUTHOR]

The problem of how to attract a robust following on social media is one of the most pressing for influencers. We study a common practice on popular microblogging platforms such as Twitter, of influencers' expanding their followings by running lotteries and giveaways. We are interested in how the lottery size and the seeding decisions influence the information propagation and the final reward for such a campaign. We construct an information-diffusion model based on a random graph, and show that the market demand curve of the lottery reward via the promotion of the social network is "S"-shaped. This property lays a foundation for finding the optimal lottery size. Second, we observe that (i) dynamic seeding could re-stimulate the spread of information and (ii) with a fixed budget, seeding at two fixed occasions is always better than seeding once at the beginning. This observation motivates us to study the joint optimization of lottery size and adaptive seeding. We model the adaptive seeding problem as a Markov Decision Process. We find the monotonicity of the value functions and trends in the optimal actions, and we show that with adaptive seeding, the reward curve is approximately "S"-shaped with respect to the lottery size. [ABSTRACT FROM AUTHOR]

We derive a dimension-reduction limit for a three-dimensional rod with material voids by means of Γ -convergence. Hereby, we generalize the results of the purely elastic setting [M. G. Mora and S. Müller, Derivation of the nonlinear bending-torsion theory for inextensible rods by Γ -convergence, Calc. Var. Partial Differential Equations 18 (2003) 287–305] to a framework of free discontinuity problems. The effective one-dimensional model features a classical elastic bending–torsion energy, but also accounts for the possibility that the limiting rod can be broken apart into several pieces or folded. The latter phenomenon can occur because of the persistence of voids in the limit, or due to their collapsing into a discontinuity of the limiting deformation or its derivative. The main ingredient in the proof is a novel rigidity estimate in varying domains under vanishing curvature regularization, obtained in [M. Friedrich, L. Kreutz and K. Zemas, Geometric rigidity in variable domains and derivation of linearized models for elastic materials with free surfaces, preprint (2021), arXiv:2107.10808]. [ABSTRACT FROM AUTHOR]

This paper presents a systematic study of the charge transport behavior of heavily doped n-type Ge layers with As and Sb. A nonequilibrium method ion implantation followed by milliseconds flash lamp annealing is applied to synthesize the n++ Ge layers (Ge:As and Ge:Sb). The resulting materials contain free electrons with a density above 3 × 1019 cm−3 and mobility more than 220 cm2/(V s). Quantum corrections to the conductance in a magnetic field are observed at low temperatures. Weak localization persists up to 30 K in Ge:Sb, while only up to 10 K in Ge:As. Using the Hikami–Larkin–Nagaoka model to fit the magnetoconductance data, we obtain the phase coherence length l ϕ of the hyperdoped Ge samples in the range of 70–163 nm. This study may pave a way to explore possible applications for quantum technologies utilizing As- and Sb-hyperdoped Ge. [ABSTRACT FROM AUTHOR]

We study how data portability affects consumer surplus and firms' profits in a two-period model with a switching cost where two firms compete under a non-negative pricing constraint. The firms can circumvent the constraint by tying another complementary free service (called "freebies") with the original service. We consider a general framework of incomplete pass-through of freebies into consumer benefit, which includes the two extreme cases of no pass-through and full pass-through as special cases. Regarding the effect on consumer surplus, data portability involves a trade-off between intensifying competition after consumer lock-in and reducing rent dissipation before consumer lock-in. We find that for an intermediate range of pass-through rates, data portability increases both consumer surplus and profits. [ABSTRACT FROM AUTHOR]

Efficient thermal management is important for both performance and efficiency improvements of thermal devices. For designing reasonable materials and structures of such devices, various design methods were proposed where the material thermal conductivity tensors were positive definite and symmetric based on the physical requirements. Here, we propose an inverse design method for thermal devices considering the thermal Hall effect, which makes the material thermal conductivity tensor asymmetric. Enlarging the design space consisting of the symmetric constitutive tensors to that of the asymmetric ones, there is a possibility of improving the theoretical performance limit of thermal devices. We formulate an inverse problem based on the free material optimization formalism, parameterizing the design space so that the physically available property could be naturally satisfied. Several numerical experiments are provided to show the validity and the utility of the proposed method. [ABSTRACT FROM AUTHOR]

Background: increasing the demand for vital pulp therapy (VPT) as a minimally invasive treatment, evolving the need for bio-inspired capping material to optimize the outcome with more predictable results. Aim: is to evaluate the biological efficacy of modified calcite paste as potential material for pulpotomy in terms of pulpal inflammatory response, dentin bridge formation and morphology. Methods: 24 lower central incisors of New Zealand rabbits were used, subdivided into two groups of 12 teeth according to sacrificing time (1 and 4 weeks), in each group, six teeth were used as the control group, the pulp is traumatically exposed and partially amputated left free of capping material, and six teeth used as the experimental group, were the amputated pulp capped with Modified Calcite (MC) paste, the cavity of both groups sealed with resin modified glass ionomere cement (pulpdent, USA). animal were sacrificed and teeth were collected for histological examination. Results: At 1-week and 4-week periods respectively, both groups showed non-significant differences in inflammatory extent, a highly significant difference in calcific bridge formation (P=0.002) and dentin morphology (P=0.002). The MC group showed faster dentin bridge formation with favourable morphology according to the scoring system in both periods compared to the control group. Conclusions: MC composite is a promising novel pulpotomy material. [ABSTRACT FROM AUTHOR]

Hole transport material free carbon‐based all‐inorganic CsPbBr3 perovskite solar cells (PSCs) are promising for commercialization due to its low‐cost, high open‐circuit voltage (Voc) and superior stability. Due to the different solubility of PbBr2 and CsBr in conventional solvents, CsPbBr3 films are mainly obtained by multi‐step spin‐coating through the phase evolution from PbBr2 to CsPb2Br5 and then to CsPbBr3. The scalable fabrication of high‐quality CsPbBr3 films has been rarely studied. Herein, an inkjet‐printing method is developed to prepare high‐quality CsPbBr3 films. The formation of long‐range crystalline CsPb2Br5 phase can effectively improve phase purity and promote regular crystal stacking of CsPbBr3. Consequently, the inkjet‐printed CsPbBr3 C‐PSCs realized PCEs up to 9.09%, 8.59% and 7.81% with active areas of 0.09, 0.25, and 1 cm2, respectively, demonstrating the upscaling potential of our fabrication method and devices. This high performance is mainly ascribed to the high purity, strong crystal orientation, reduced surface roughness and lower trap states density of the as‐printed CsPbBr3 films. This work provides insights into the relationship between the phase evolution mechanisms and crystal growth dynamics of cesium lead bromide halide films. [ABSTRACT FROM AUTHOR]

This paper researches the free vibrations and corresponding material parameters of a functional gradient graphene platelets-reinforced composite (FG-GPLRC) cantilever torsional plates with both pore and graphene variations in the transverse direction. Utilizing the feature of closed-cell cellular solids, the mixture rule, and the modified Halpin–Tsai model, the material parameters of the composite are determined for different volume fractions of component materials. Then, using the classical plate theory (CLPT), the Rayleigh–Ritz technique and polynomials, the dynamic equation that can be used to obtain the free vibration mode shapes and frequencies of the rotating cantilever torsional plate is given. Comparison studies with the previous calculation results from available literature and the finite element (FE) models of cantilever plates are conducted, and the correctness of the present theoretical formulation and numerical calculation is verified. Finally, the effects of graphene platelet (GPL) distribution, porosity distribution (PD), GPL content, rotational speed, and average geometric size of GPL on free vibrations of the system are studied in depth. [ABSTRACT FROM AUTHOR]

This study assessed the influence of the type of endodontic access cavity on endodontic reintervention. Twenty mandibular central incisors were distributed into two groups (n = 10): TradAC group—traditional access cavities and UltraAC.Inc group—ultraconservative access cavities. After endodontic access, the root canals were prepared and obturated by the single cone technique. The filling material was removed with the Reciproc R25 instrument, followed by reinstrumentation with the R40 instrument. Images acquisition of each root canal hemisection was performed in a stereomicroscope to quantify the amount of remaining filling material. The amount of remaining filling material attached to the root canal walls was expressed in square millimeter (mm2). Data were statistically analyzed (one-way ANOVA and post hoc Student's t-tests). There was no statistically significant difference between TradAC and UltraAC.Inc groups (p > 0.05). None of the tested endodontics' access showed root canal walls completely free of filling material. Ultraconservative access cavities in mandibular incisors had no negative impact on the filling material removal. [ABSTRACT FROM AUTHOR]

Shape-controlled 3D tissues resemble natural living tissues in human and animal bodies and are essential materials for developing and improving technologies in regenerative medicine, drug discovery, and biological robotics. In previous studies, shape-controlled 3D tissues were fabricated using scaffold structures or 3D bioprinting techniques. However, controlling the shape of 3D tissues without leaving non-natural materials inside the 3D tissue and efficiently fabricating them remains challenging. In this paper, we propose a novel method for fabricating shape-controlled 3D tissues free of non-natural materials using a flexible high-porosity porous structure (HPPS). The HPPS consisted of a micromesh with pore sizes of 14.87 ± 1.83 μm, lattice widths of 2.24 ± 0.10 μm, thicknesses of 9.96 ± 0.92 μm, porosity of 69.06 ± 3.30%, and an I-shaped microchamber of depth 555.26 ± 11.17 μm. U-87 human glioma cells were cultured in an I-shaped HPPS microchamber for 48 h. After cultivation, the 3D tissue was released within a few seconds while maintaining its I-shape. Specific chemicals, such as proteolytic enzymes, were not used. Moreover, the viability of the released cells composed of shape-controlled 3D tissues free of non-natural materials was above 90%. Therefore, the proposed fabrication method is recommended for shape-controlled 3D tissues free of non-natural materials without applying significant stresses to the cells. [ABSTRACT FROM AUTHOR]

In recent years, the encroachment of the upstream manufacturer on the retailer has become increasingly frequent. This study focuses on the influence of the retailer's freebies promotion on the manufacturer's encroachment decisions. The manufacturer produces products and wholesales them to the downstream retailer, and then the retailer sells them directly to the end retail market. To obtain more profits, the retailer can decide whether to offer freebies before the promotion day. We first obtain the manufacturer's encroachment decisions and promotion decisions of the retailer by comparing their payoffs under simultaneous quantity decisions. Then, we characterize the impact of firms' decisions on each other. Finally, we change the sequences for quantity decisions to verify the robustness of our results. Our analysis shows that compared with the retailer offering freebie promotion, the manufacturer prefers to encroach on the retailer under no freebie promotion. Furthermore, compared with sequential quantity decisions, the manufacturer prefers simultaneous quantity decisions. From the perspective of the retailer, the adoption of freebie promotion can prevent manufacturer encroachment to a certain extent. [ABSTRACT FROM AUTHOR]

Citrus hosts various phytopathogens that have impacted productivity, including viroids. Missing data on the status of viroids in citrus in Palestine were not reported. This study was aimed to detect any of Citrus exocortis viroid (CEVd), Citrus viroid-III (CVd-III), and Citrus viroid-IV (CVd-IV) in the Palestinian National Agricultural Research Center (NARC) germplasm collection Field inspections found symptoms such as leaf epinasty; vein discoloration, and bark cracking on various citrus varieties. RT-PCR revealed a significant prevalence of CVd-IV; CEVd and CVd-III (47%, 31%, and 22%; respectively). CVd-III variants with 91.3% nucleic acid sequence homology have been reported. The sequence of each viroid were deposited in GenBank as (OP925746 for CEVd, OP902248 and OP902249 for CVd-III-PS-1 and -PS-2 isolates, and OP902247 for CVd-IV). This was the first to report three of citrus viroids in Palestine, appealing to apply of phytosanitary measures to disseminate healthy propagating materials free from viroids. [ABSTRACT FROM AUTHOR]

This paper summarizes an approach to crystal growth that was published in parts in various articles over the course of 25 years by the present author and his colleagues. Evidence for this approach, which is confirmed in detail by data in the cited publications and in the figures and equations in the supplementary material that accompanies this paper (see the Online Materials Deposit item AM-24-18851. Online Materials are free to all readers. Go online, via the table of contents or article view, and find the tab or link for supplemental materials.), comes mainly from the shapes of crystal size distributions (CSDs). Such distributions reveal the growth histories of natural minerals and synthetic compounds, histories that can be used to make geological interpretations and to guide industrial syntheses. CSDs have three fundamental shapes: log-normal, asymptotic, and Ostwald. These shapes result from different degrees of supersaturation near the time of nucleation. The first two distribution shapes form according to the Law of Proportionate Efect (LPE) at moderate supersaturation, and the latter rare distribution forms by Ostwald ripening at large supersaturation. Initially, the first two distributions have mean diameters of up to tens of nanometers and grow by surface-limited growth kinetics. The slow step in this reaction is the incorporation of nanoparticles (bits of crystal or adparticles) onto the crystal surface. As the crystals become larger, their demand for nutrients, as calculated by the LPE, increases exponentially. Then the slow step in the reaction changes to the rate of transfer of nutrients to the crystal (supply- or transport-limited growth). Crystal diameters often grow the most during this latter stage, and the initial CSD shapes that originally formed during surface-limited growth are retained and scaled up proportionately. Proportionate growth during the supply-limited stage can be simulated approximately by multiplying the diameter of each crystal in a distribution by a constant. Crystals can also grow by a constant rate law in which a constant length is added to each crystal diameter in the distribution. This rare process causes the original CSD to narrow so that its initial shape is not preserved. The growth law that prevails, either proportionate or constant, is determined by the manner in which nutrients are supplied to the crystal. Supply is by advective flow during proportionate growth, with the nutrient solution moving with respect to the crystals. Constant growth relies on the random difusion of nutrients through a quiescent solution. Proportionate growth is by far the most common growth law, and therefore, nutrient supply by difusion alone during crystal growth is uncommon. Distributions formed by Oswald ripening and those formed by other rare processes are also discussed. During Ostwald ripening, nucleation caused by mixing reactants at large supersaturation forms crystals that are extremely fine and numerous. The larger crystals grow at the expense of the finer, less stable crystals, thereby forming, on completion, the universal steady-state CSD shape predicted by the Lifshitz-Slyozov-Wagner (LSW) theory. This unique CSD shape, as well as other rare shapes, then are scaled up to larger sizes by supply limited proportionate growth. [ABSTRACT FROM AUTHOR]

Ultrafine powders of phases in the system (1 – y)Bi0.8Ba0.2Fe0.8Ti0.2O3–y(Ba0.85Ca0.15)Ti0.9Zr0.1O3 (y = 0.05–0.30) were synthesized at a temperature of 650–680°C by a technology in which the precursors were Fe(III) and Bi(III) nitrates, peroxynitrate complexes of Ti(IV) and Zr(IV), and barium and calcium hydroxides. The base phases of the powder were doped with manganese compounds to reduce the electrical conductivity of the ceramic samples. A special sintering procedure including air hardening of the ceramic samples was used to increase the longitudinal piezoelectric modulus d33 of piezoelectric elements and the operating temperature. In the best piezoceramic samples made by the proposed technology, the Curie temperature TC is above 550°C, the longitudinal piezoelectric modulus d33 under standard conditions is ≥125 pC/N, and the operating temperature reaches 340–350°C. [ABSTRACT FROM AUTHOR]

Although stadium giveaways are the most common type of promotion used in Major League Baseball to increase demand, most teams supply fewer giveaway items than there are tickets sold. This study argues that giveaway availability is a major component of teams' promotion strategies and has been largely overlooked in the literature. The authors document the choice of giveaway availability across all Major League Baseball teams over an 8-year period and demonstrate that attendance increases with giveaway availability up to the point where there are enough giveaway items to serve 40% of a stadium's capacity. Roughly two thirds of teams set giveaway availability in a fashion that is consistent with the standard price discrimination rationale for promotions found in the economic and marketing literatures. The remaining teams exhibit levels of high availability, indicating an additional investment into fan lifetime value, which is corroborated by these teams' unique fan relationships. [ABSTRACT FROM AUTHOR]

Two‐photon lithography (TPL) is an advanced high‐resolution additive manufacturing technique for objects with feature sizes between 100 nanometers to tens of micrometers and an overall footprint of up to hundreds of micrometers. With recent advances in the TPL technique, writing speeds are becoming faster, rendering the method feasible to print high‐resolution microfluidic chips with a footprint in the centimeter range within a reasonable time frame. In this work, a process flow to fabricate embedded microfluidic chips with channel diameters down to 30 µm is developed. To address the particular difficulty of washing the embedded channels free of uncured material, introduces a developing scheme based on a 3D printed chip‐to‐world‐interface to connect the chips to a pressure‐driven pump. This setup is leakage‐free up to a pressure of 6.9 bar for faster and safer development of embedded microfluidic devices. It manufactures meander chips with channel lengths up to 20 cm, droplet generator chips, and cell sorting chips based on deterministic lateral displacement with pillar diameters of 30 µm and pillar spacing of 4 µm. TPL of microfluidic chips will enable rapid manufacturing of novel designs, significantly reducing concept‐to‐chip times with high resolution in a reasonable amount of time. [ABSTRACT FROM AUTHOR]

The gravity flow of a granular material between two vertical walls separated by a width $2W$ is simulated using the discrete element method (DEM). Periodic boundary conditions are applied in the flow (vertical) and the other horizontal directions. The mass flow rate is controlled by specifying the average solids fraction $\bar {\phi }$ , the ratio of the volume of the particles to the volume of the channel. A steady fully developed state can be achieved for a narrow range of $\bar {\phi }$ , $\bar {\phi }_{max} \geq \bar {\phi } \geq \bar {\phi }_{cr}$ , and the material is in free fall for $\bar {\phi }. For an intermediate range of $\bar {\phi }$ ($\bar {\phi }_{cr} > \bar {\phi } \geq \bar {\phi }_{min}$), there are oscillations in the horizontal coordinate of the centre of mass, velocity components and stress. As $\bar {\phi }$ decreases in the range $\bar {\phi }_{cr} > \bar {\phi } \geq \bar {\phi }_{min}$ , the amplitude of the oscillations increases proportional to $\sqrt {\bar {\phi }_{cr} - \bar {\phi }}$ and the frequency appears to tend to a non-zero value as $\bar {\phi } \rightarrow \bar {\phi }_{cr}$ , indicating a supercritical Hopf bifurcation. The relation between the dominant frequency and the higher harmonics of the position, velocity and stress fluctuations are explained using the momentum balance. It is found that dissipation in the inter-particle and particle–wall contacts is critical for the presence of an oscillatory state. [ABSTRACT FROM AUTHOR]

Black wattle (Acacia mearnsii De Wild.) barks are residues produced by tannin industries in huge quantities, which are normally discharged on environmental or used for energy production. Therefore, this study aimed to evaluate the use of black wattle bark residues as a raw material on obtaining of a rich-cellulose material by alkaline (MET1), acetosolv (MET2), and organosolv (MET3) procedures. The results obtained indicated that the alkaline methodology, followed by a bleaching step (MET1), promoted klason lignin and hemicellulose removals more efficiently. It was possible to observe that better results were achieved using NaOH concentration of 6% (wt%), at 65 °C for 2.5 h, presenting a yield of 63.24 ± 1.25%, and a reduction on klason lignin content of almost 90.45%. Regarding the bleaching step, it was possible to obtain a material free of non-cellulosic compounds with a yield of 78.28 ± 1.48%. Thermogravimetric analysis indicated the removal of lignin and hemicellulose as well as an increase in cellulose degradation temperature, due to changes in crystalline phases. According to X-ray diffraction (XRD), the procedures employed have led to an increase in crystallinity from 66.27 to 91.78% due to the removal of non-cellulosic compounds. Scanning electron microscopy (SEM) showed morphological alterations in accordance with the removal of non-cellulosic compounds. [ABSTRACT FROM AUTHOR]

Using Stimulus-Organism-Response (S-O-R) model, the study examines whether two environmental stimuli, 'freebie type' and 'focal item price', during a gourmet food estore sales promotion campaign, influence Generation Z Indians' online purchase intentions, with consumer confidence and perceived risk as mediators. Intercept data was collected from 392 subjects in eight Indian metropolises, using a cross-sectional survey design and qualitative study. The hypotheses were tested using structural equation modeling and associated tests. For qualitative analysis, inductive content analysis was used. The study reveals that the price of the focal item and the type of freebie influence customer confidence and perceived risk, which in turn influences consumers' online purchase intention. The results show that utilitarian freebies are the most popular and identify important associated cognitive dissonance elements. Being one of the first such studies, it reveals consumer behavior during food marketing campaigns and informs e-gourmet food retailers of the crucial aspects influencing Gen Z's purchasing intentions. Additionally, it recommends strategies to increase consumer confidence and reduce perceived risk, which would aid in resolving cognitive dissonance. [ABSTRACT FROM AUTHOR]

A new series of triphenylamine (TPA)‐functionalized isomeric polythiophenes are developed as hole transporting materials (HTM) for inverted tin‐based perovskite solar cells (TPSCs). Bithiophene (BT) is first functionalized with two TPA (electron donor; D) at 3 and 5 positions to give two structural isomeric compounds (3BT2D and 5BT2D). The functionalized BT2Ds are then coupled with 3,3′‐bis(tetradecylthio)‐2,2′‐bithiophene (SBT‐14)/3,3′‐ditetradecyl‐2,2′‐bithiophene (BT‐14) to produce structural isomeric polythiophenes (1‐4), which are compared to conventional poly[N,N″‐bis(4‐butylphenyl)‐N,N″‐bis(phenyl)‐benzidine] (poly‐TPD) as HTMs for TPSCs. With the appropriate alignment of energy levels with regard to the perovskite layer, the TPA‐functionalized polymers‐based TPSCs exhibit enhanced operational stability and efficiency. Moreover, the long thiotetradecyl chain in SBT‐14 with intramolecular S(alkyl)∙∙∙S(thio) interactions restricts the molecular rotation and has a strong impact on the molecular solubility and wettability of the film during device fabrication. Among all the polymers studied, TPSCs fabricated with 3‐SBT‐BT2D polymer exhibit the highest hole mobility as well as the slowest charge recombination and achieve the highest power conversion efficiency of 8.6%, with great long‐term stability for the performance retaining ≈90% of its initial values for shelf storage over 4000 h, which is the best efficiency for non‐PEDOT:PSS‐based TPSCs ever reported. [ABSTRACT FROM AUTHOR]

In two-player Tullock contests with endogenous timing of moves, the weak player moves early and the strong player follows. This order of moves is the third-best outcome for a contest organiser as it leads to a contest with lower aggregate effort compared to a contest where the players move in reverse order (first best) or simultaneously (second best). We propose that if the contest organiser—who does not know ex ante which player is the strong and which is the weak one—offers a lower price (effort cost) to the player(s) who choose(s) to exert effort early, she can achieve a greater payoff by affecting the contestants' sequence of moves. We show that there exists no price that generates the first-best outcome. However, there is a price (or a range of prices) that induces both players to move early and receive it, leading to the second-best outcome. We also discuss the case where both players move early but only one receives the low price, e.g., lobbying or Instagram "giveaway" contests. [ABSTRACT FROM AUTHOR]

Bio-inspired (biomimetic) materials, which are inspired by living organisms, offer exciting opportunities for the development of advanced functionalities. Among them, bio-inspired superhydrophobic surfaces have attracted considerable interest due to their potential applications in self-cleaning surfaces and reducing fluid resistance. Although the mechanism of superhydrophobicity is understood to be the free energy barrier between the Cassie and Wenzel states, the solid-surface technology to control the free energy barrier is still unclear. Therefore, previous studies have fabricated solid surfaces with desired properties through trial and error by measuring contact angles. In contrast, our study directly evaluates the free energy barrier using molecular simulations and attempts to relate it to solid-surface parameters. Through a series of simulations, we explore the behavior of water droplets on surfaces with varying values of surface pillar spacing and surface pillar height. The results show that the free energy barrier increases significantly as the pillar spacing decreases and/or as the pillar height increases. Our study goes beyond traditional approaches by exploring the relationship between free energy barriers, surface parameters, and hydrophobicity, providing a more direct and quantified method to evaluate surface hydrophobicity. This knowledge contributes significantly to material design by providing valuable insights into the relationship between surface parameters, free energy barriers, and hydrophilicity/hydrophobicity. [ABSTRACT FROM AUTHOR]

Inkjet‐printing is considered an emerging manufacturing process for developing perovskite solar cells (PSCs) with low material wastes and high production throughput. Up‐to‐now, all case studies on inkjet‐printed PSCs are based on the exploitation of toxic solvents and/or high‐molarity perovskite precursor inks that are known to enable the development of high‐efficiency photovoltaics (PVs). The present study provides a new insight for developing lower‐toxicity, high performance and stable (for more than 2 months) inkjet‐printable perovskite precursor inks for fully ambient air processed PSCs. Using an ink composed of a green low vapor pressure noncoordinating solvent and only 0.8 m of perovskite precursors, the feasibility of fabricating high‐quality and with minimum coffee‐ring defects, annealing‐free perovskite absorbent layers under ambient atmosphere is demonstrated. Noteworthily, the PSCs fabricated using the industry‐compatible carbon‐based hole transport material free architecture and the proposed ink present an efficiency >13% that is considered on the performance records for the under‐consideration PV architecture employing an inkjet‐printed active layer. Outstanding is also found the stability of the devices under the conditions determined by the ISOS‐D‐1 protocol (T95 = 1000 h). Finally, the perspective of upscaling PSCs to the mini‐module level (100 cm2 aperture area) is demonstrated, with the upscaling losses to be as low as 8.3%rel dec−1 per upscaled active area. [ABSTRACT FROM AUTHOR]