bluuebunny/crossref_metadata_2025 huggingface dataset:
A new soft‐switching high step‐up DC–DC converter with low voltage stress
Authors: Sharma Preeti , Hasanpour Sara , Kumar Rajneesh
Published: June 2024

This paper proposes a new high step‐up DC–DC converter with zero input current ripple for renewable energy sources applications, such as fuel cells. In this topology, a coupled inductor and a multiplier cell are used to achieve high voltage gains. The power switch in this proposed circuit turns on under zero voltage switching conditions. An active switch limits the maximum voltage stress across the main power switch. Moreover, all circuit diodes of the converter turn off without a reverse recovery problem. A detailed analysis of a high‐gain step‐up DC–DC converter is studied along with improved efficiency. The ripple cancellation of the input stage of the converter is done by adding an input inductor and capacitor. By including the parasitic elements, an approximate loss analysis was performed in PSIM and found the maximum efficiency of ∼96% in simulation and ∼94% in hardware for 200 W power level design for 30 V input voltage. Later on, the converter laboratory hardware prototype can be developed with selected parameters, and finally, experimental results have been used to validate the properties of the converter.
Effects of Cadmium and Nickel Mixtures on Multiple Endpoints of the Microalga Raphidocelis subcapitata
Authors: Reis Larissa Luiza dos , Abreu Cínthia Bruno , Gebara Renan Castelhano , Rocha Giseli Swerts , Longo Elson , Mansano Adrislaine da Silva , Melão Maria da Graça Gama
Published: June 2024

It is crucial to investigate the effects of mixtures of contaminants on aquatic organisms, because they reflect what occurs in the environment. Cadmium (Cd) and nickel (Ni) are metals that co-occur in aquatic ecosystems, and information is scarce on their joint toxicity to Chlorophyceae using multiple endpoints. We evaluated the effects of isolated and combined Cd and Ni metals on multiple endpoints of the chlorophycean Raphidocelis subcapitata. The results showed that Cd inhibited cell density, increased reactive oxygen species (ROS) production (up to 308% at 0.075 mg L−1 of Cd), chlorophyll a (Chl a) fluorescence (0.050–0.100 mg L−1 of Cd), cell size (0.025–0.100 mg L−1 of Cd), and cell complexity in all concentrations evaluated. Nickel exposure decreased ROS production by up to 25% at 0.25 mg L−1 of Ni and Chl a fluorescence in all concentrations assessed. Cell density and oxygen-evolving complex (initial fluorescence/variable fluorescence [F0/Fv]) were only affected at 0.5 mg L−1 of Ni. In terms of algal growth, mixture toxicity showed antagonism at low doses and synergism at high doses, with a dose level change greater than the median inhibitory concentration. The independent action model and dose-level–dependent deviation best fit our data. Cadmium and Ni mixtures resulted in a significant increase in cell size and cell complexity, as well as changes in ROS production and Chl a fluorescence, and they did not affect the photosynthetic parameters. Environ Toxicol Chem 2024;43:1855–1869. © 2024 SETAC
Dementia care landscape in Nepal: Understanding the context, barriers, and opportunities for the development of a national dementia care plan
Authors: Thapa P. , Marahatta K. , Upadhyay Raj S. , Sapkota N. , Baral P. , Lama S. , Kamholz B. , Paudel S. , Basnet M.
Published: June 2024

Objective

This study was conducted to comprehensively understand the context, barriers, and opportunities for improving dementia care, treatment, and support. The objective is to guide the development of a national dementia care plan.

Methodology

This document review was conducted by analyzing literature available in the public domain, including scientific publications, project documents/reports, media reports, and hospital records. Additionally, annual reports published by the Department of Health Services, national census and demographic and health survey reports, Old Age Homes, and other relevant government reports were examined. Firsthand information was gathered from relevant stakeholders based on the World Health Organization's situational analysis framework for dementia plans. This framework encompasses four domains: Policy context (national ministries, legislation, policies, strategies, plans related to dementia, mental health, aging, and disability), service delivery assessment (health and social care workforces, services, support and treatment programmes, and promotion of awareness and understanding), and epidemiological indicators (prevalence and incidence rates of dementia, risk factors). Ethical clearance was obtained from the Institutional Review Committee (IRC) of B.P. Koirala Institute of Health Sciences (IRC no.2658/023).

Results

Existing policies in Nepal inadequately address the needs of people with dementia and their caregivers. Concerning health services, the Government of Nepal provides financial subsidies to individuals diagnosed with dementia; however, numerous hurdles impede access to care. These obstacles include geographical and structural barriers, an inefficient public healthcare system, weak governance, financial constraints, low awareness levels, stigma, and inadequate workforce. Furthermore, the absence of robust nationally representative epidemiological studies on dementia in Nepal hampers the development of evidence‐based plans and policies. Similarly, there are no interventions targeted at caregivers of people with dementia, and no initiatives for dementia prevention are in place.

Conclusions

This review underscores the urgent need to formulate a comprehensive national dementia care plan to address the growing challenges. Key priority action areas include the integration of dementia care into primary healthcare services, training workforce to provide the care, increasing awareness, mitigating stigma, developing caregiver support programs, and initiating high‐quality research to inform evidence‐based policymaking.
Mobile bearing shows larger rollback motion than fixed bearing in total knee arthroplasty using a medial stabilising technique with a navigation system
Authors: Tsushima Takahiro , Sasaki Eiji , Sasaki Shizuka , Oishi Kazuki , Sakamoto Yukiko , Kimura Yuka , Otsuka Hironori , Yamamoto Yuji , Tsuda Eiichi , Ishibashi Yasuyuki
Published: June 2024

Purpose

This study aimed to investigate the intraoperative knee kinematics of cruciate‐retaining total knee arthroplasty with a medial stabilising technique (MST‐TKA) and compare the kinematics between mobile‐ and fixed‐bearing MST‐TKAs. We hypothesised that mobile‐bearing MST‐TKA would result in greater physiological kinematic motion than fixed‐bearing MST‐TKA.

Methods

Twenty‐one and 20 knees underwent mobile‐ and fixed‐bearing MST‐TKAs using a navigation system (Orthopilot® ver. 6.0; B. Braun Aesculap), respectively. In the preoperative and postoperative kinematic analysis, the knee was moved manually from 0° to 120°, and femoral anteroposterior translations of the medial femoral condyle (MFC) and lateral femoral condyle (LFC) were recorded every 0.1 s from 0° to 120°. Data were subsequently extracted from the software every 10° of flexion and compared between the two groups, and the correlation coefficients between preoperative and postoperative kinematics were calculated.

Results

In the postoperative analysis, the MFC in the mobile‐bearing group showed significant posterior translation at 100°, 110° and 120° compared to the fixed‐bearing group (p < 0.01). Similarly, the LFC in the mobile‐bearing group showed significant posterior translation at 100°, 110° and 120° compared to the fixed‐bearing group (p < 0.05, p < 0.01 and p < 0.05, respectively). In the mobile‐bearing group, the preoperative and postoperative anteroposterior translations of the MFC and LFC were correlated (p < 0.01), while in the fixed‐bearing group, there was no correlation.

Conclusion

The femoral rollback motion in the mobile‐bearing MST‐TKA correlated with the preoperative kinematics and was larger than that in the fixed‐bearing group.

Level of Evidence

Level II, therapeutic prospective cohort study.
Testing the ecological footprint of economic growth in developing countries. The case of Vietnam
Authors: Nguyen Minh‐Quang , Dimou Michel , Vu Thi Thu Huong , Schaffar Alexandra , The Cong Phan , Nguyen Ngoc Quynh
Published: June 2024

This study focuses on the relationship between economic growth and environmental degradation, by testing the Environmental Kuznets Curve hypothesis in Vietnam, a main export‐oriented country that features a long period of economic growth. The main originality of this work is that, unlike previous studies, it uses ecological footprint as the main indicator for environmental degradation. This allows to reconsider the results from previous studies that only focus on CO2 emissions performances. The cointegration between the analysed variables is investigated using the autoregressive distributed lag (ARDL) approach. To determine the parameters of the Environmental Kuznets Curve in the sample, this work additionally analyses long‐ and short‐run estimations. The paper shows that the EKC hypothesis holds in the long term for Vietnam when using ecological footprint. Nevertheless, it also shows that not only growth but also primary energy consumption contributes to increased environmental destruction. An active ecological policy and the decrease of fossil energy use seem necessary to allow Vietnam to keep a high level of economic growth and reduce environmental degradation.
Adopting Underdogs' Ideas Triggers Fairness? When and How Underachievers' Voice Endorsement Promotes Team Voice
Authors: Ni Dan , Wu Wen , Wu Shaoxue (Eric) , Zhang Yihua , Chen Chong , Zhang Rui
Published: June 2024

Previous research on employee voice endorsement has mostly focused on its antecedents. In particular, most scholars seem to consider employee voice endorsement as a factor influencing only the voicers themselves. Thus, they have ignored its interpersonal influences, such as at the team level. The present study explores the influence of underachievers' voice endorsement on team voice. Specifically, we not only examine a boundary condition in this relationship but also develop and test a new construct of supervisors' voice judgment fairness as a mediator. Data from two multi‐wave, multi‐source surveys show that when underachievers' voice quality is higher (versus lower), the positive relationship between underachievers' voice endorsement and supervisors' voice judgment fairness is stronger, which in turn enhances team voice. These results offer meaningful theoretical implications for the voice endorsement literature and practical implications for organizations.
Self‐Regulation Prompts Improve Creative Performance
Authors: Zielińska Aleksandra , Lebuda Izabela , Czerwonka Marta , Karwowski Maciej
Published: June 2024

While people approach creative actions in diverse ways, navigating them effectively requires self‐regulatory effort. In this preregistered experiment, we examined whether simple self‐regulation prompts, provided across the stages of the creative process, make the outcomes more creative. Participants (N = 332) engaged in one of three creativity tasks—designing a logo, writing a short story, or preparing a greeting card—and documented their ongoing progress with photos. During the task, half of the participants received prompts tailored to their task progress, encouraging the employment of various self‐regulatory mechanisms (e.g., uncertainty acceptance, adjusting approach). Consistent with our predictions, promoting a strategic approach throughout the task led participants to develop more creative products than those in the no‐prompt condition. Moreover, we demonstrated two indirect paths behind the prompts' effectiveness: first, via enhancing positive active emotions, and second, through fostering a greater time commitment to the task. On a theoretical level, the proposed prompting approach highlights the advantages of self‐regulatory engagement during creative actions beyond solely idea generation strategies. Methodologically, our study underscores the simplicity of such interventions and their potential broad applicability.
A compact broadband RF rectifier using two‐stage microstrip lines
Authors: Liu Yang , Liu Wenbo , Yin Dawei , Wang Tao , Huang Xingyu , Qin Jinghang
Published: June 2024

This paper simulates and measures a compact broadband rectifier for voltage doubler Schottky diode. Among them, a two‐stage microstrip line impedance matching network for voltage doubling circuits is used. The imaginary part of the diode impedance is limited by the short‐circuit branch. The impedance conversion transmission line matches the impedance to 50 Ω. The impedance matching in the circuit is only realized by two‐stage microstrip lines, which reduces the physical size of the rectifier and makes the rectifier more compact. Judging the measurement results from 0.8 to 2.5 GHz, the conversion efficiency is greater than 30% at 0 dBm, the bandwidth is 103%, and the maximum conversion efficiency reaches 66.3% at 8 dBm. In addition, the compact size of the rectifier is 23 × 20 mm2.
Design and investigation of celastrol‐peptide nanoassemblies and their binding interactions with superoxide dismutase 1 and its mutants
Authors: Goncalves Beatriz G. , Phan Chau Anh N. , Biggs Mary A. , Hunt Hannah L. , Banerjee Ipsita A.
Published: June 2024

The misfolding and aggregation of superoxide dismutase 1 (SOD1) and its mutants has been implicated in amyotrophic lateral sclerosis (ALS). In this study, we have created three peptide conjugates with the antioxidant pentacyclic terpene celastrol and examined their interactions with SOD1 and its mutants A4V and G93A. The peptides YYIVS, MPDAHL, and GSGGL are derived from natural sources and are known for their inherent antioxidant properties. Docking studies revealed that most conjugates showed strong binding with the metal binding and electrostatic loops as well as the β1, β5, and β6 hydrophobic core of SOD1. The conjugates were synthesized and self‐assembled into nanoassemblies. Surface plasmon resonance studies further confirmed the binding interactions of the nanoassemblies with the SOD1 proteins. The nanoassemblies were found to internalize into HEK293T cells. The HEK 293T cells were then transfected with GFP fused WT (Wild Type), A4V and G93A SOD1 mutants. Flow cytometry revealed that treatment with celastrol‐peptide nanoassemblies, affected the fluorescence of the SOD1 protein, implying their role in modulating SOD1, particularly for the mutants. N–Acetyl–Leu–Leu–Norleucinal (ALLN) induced SOD1 aggregation was also affected upon treatment with the nanoassemblies. These results suggest that the nanoassemblies may potentially modulate the activity and structure of SOD1.
Willingness of rural and urban citizens to undertake pollinator conservation actions across three contrasting European countries
Authors: Geppert Costanza , Franceschinis Cristiano , Fijen Thijs P. M. , Kleijn David , Scheper Jeroen , Steffan‐Dewenter Ingolf , Thiene Mara , Marini Lorenzo
Published: June 2024

Over the last two decades, ecological and conservation studies on pollinator insects have increased significantly. However, scientific evidence alone is not enough to translate knowledge into policy and into changes in behaviour. To reduce the gap between scientific knowledge on conservation actions and their actual uptake, one should understand the socio‐psychological drivers of people's willingness to undertake these actions.

Here, we investigated the socio‐psychological factors influencing individual behaviour in favour of conservation interventions for pollinators in rural versus urban environments across three European countries: Germany, Italy and the Netherlands. We administered an online questionnaire to 4541 respondents stratified by nationality, environment, age and gender.

Despite regional differences in socio‐cultural and economic conditions, individuals from Germany, Italy and the Netherlands living in both rural or urban environments shared similar socio‐psychological drivers to protect pollinators. People intended to take action to protect pollinators when they felt morally obliged to, when their social environment supported pollinator protection, when they believed their individual behaviour had an impact, and when they engaged frequently in outdoor activities.

Interestingly, specific values held towards pollinators, such as their right to exist, seemed much more important predictors of activating norms that promote conservation actions compared to increasing general environmental concern. In all countries, among the conservation actions, the most likely to be implemented was planting flowers, while one of the most unlikely was participating in monitoring activities.

Synthesis and applications. People from three contrasting European countries living in both rural and urban landscapes were mostly driven by the same socio‐psychological factors to help pollinator insects. Therefore, our results offer several practical recommendations to promote pollinator conservation across Europe. First, conservation practitioners interested in pollinator conservation should pay greater attention to values specific to pollinators, as they seemed more important behaviour predictors than general care for the environment. Second, engaging people in conservation efforts can be accomplished by increasing awareness about the vital roles that pollinators play within ecosystems. Lastly, promoting simple nature‐based activities such as wildlife observation, and gardening can help foster a sense of connection to and appreciation for pollinators and pollination.

Read the free Plain Language Summary for this article on the Journal blog.
Effect of silane coupling agent grafted glycidyl methacrylate on hollow microsphere/natural rubber composites
Authors: Zhao Meng , Duan Hao , Peng Keyu , Dong Juyuan , Chen Haiming , Lin Guangyi , Jing Yuan , Li Yang , Lv Ruifang
Published: June 2024

To improve the interfacial bonding between hollow microspheres (RiM01) and natural rubber (NR), the silane coupling agents γ‐aminopropyltriethoxysilane (KH550) and γ‐methacryloyloxypropyltrimethoxysilane (KH570) are used in this study as intermediate reaction platforms for the modification of (RiM01) with glycidyl methacrylate (GMA), respectively. In the process, GMA reacts with KH550 and KH570 through epoxy group ring‐opening and free radical polymerization, respectively. Different NR/RiM01@GMA composites are prepared by a mechanical blending method. The results show that the addition of GMA improves the interfacial bonding between RiM01 and NR, and enhances the vulcanization rate and cross‐linking degree of the rubber composites. When KH550 is used as the reaction platform, the tensile strength of the rubber composites increases by 24% compared to composites with unmodified RiM01, while when KH570 is used, the tensile strength increases by 18%. Additionally, the tear strength and abrasion resistance of the rubber composites increase by 13% and 15%, respectively, when KH570 is used as the reaction platform. At the same time, the filler‐matrix interaction is strongest when KH570 is used as the reaction platform, and the rubber composites exhibit the lowest rolling resistance and the best resistance to heat and oxygen aging.

Highlight

Modification of hollow microspheres by grafting GMA with KH550 and KH570, respectively.

Improvement of rubber composite properties after modification

GMA improves the interfacial bonding between hollow microspheres and rubber.
Preparation of h‐BN/PMMA composites by in situ polymerization and research on their structure and properties
Authors: Wu Lulu , Wang Yanzhi , Gao Yafei , Zhang Yiru , Zhou Lei , Li Jing , Zhang Jianmin
Published: June 2024

Inorganic fillers like hexagonal boron nitride (h‐BN) have the potential to enhance the thermal conductivity of polymer mixtures. However, it has been restricted due to poor dispersion of particles in polymer matrices by melt mixing process. The addition of inorganic powders into sticky prepolymer is expected to alleviate the aggregation of powders. In this paper, h‐BN/polymethyl methacrylate (PMMA) composites were prepared by in situ polymerization of methyl methacrylate (MMA) with 5 and 20 μm of h‐BN particle as fillers respectively, for even distribution of fillers with in composites. The structures and properties of composites were characterized by FT‐IR, DSC, TGA, SEM, laser thermal conductivity meter and universal electronic tester. By SEM, it can be seen that a highly uniform dispersion of h‐BN in PMMA. When the mass fraction of h‐BN is 20 wt%, the thermal conductivity of the composites is increased by 107% for 5 μm h‐BN and 189% for 20 μm h‐BN, respectively. With the mass constituting of 5 wt% h‐BN, majority of mechanical characteristics of the composite, such as tensile strength, tensile modulus, along with impact strength, are enhanced, alongside a decrease in bending strength. This work would provide a filling strategy of h‐BN into the polymer matrices to achieve uniform dispersion, and enhance both the thermoconductivity and mechanical strength of thermoplastic composites.

Highlights

A technique for creating h‐BN/PMMA composites using in suit redox polymerization.

Ehancing the thermal conductivity of these composites is achievable through the even distribution of h‐BN flakes within the PMMA matrix.

It provides a reference for the design of future h‐BN/PMMA composites with favorable the thermal conductivity which achieves a good balance between performance and cost.
Experimental investigation of the effect of fabric wrapping method and autoclave curing on the mechanical and thermal degradation of carbon nanotube doped and undoped carbon composite pipes
Authors: Kayrıcı Mehmet , Taser Hasan Huseyin
Published: June 2024

Although it is seen in the literature that composite pipes are produced by filament winding, there are limited number of studies on the use of fabric wrapping and autoclave. In this study, in order to fill this gap and contribute to the literature and industry, composite pipes were produced using fabric wrapping and autoclave methods together and their mechanical and thermal properties were investigated. The effect of carbon nanotube (CNT) reinforcement on these properties was also investigated. According to low velocity impact (LVI) test, 10%–25% impact strength increase was observed with CNT reinforcement. Thermogravimetric analysis (TGA) shows that mass loss decreased by ⁓10% and the degree of thermal degradation increased by ⁓10%. In dynamic mechanical analysis (DMA), it is observed that epoxy glass transition temperature (Tg) increased by 11% with CNT reinforcement. At the end of the study, the mechanical and thermal properties of the pipes produced by autoclave and fabric wrapping methods were improved compared to the literature and contributed to science and therefore to the increased use of prepreg carbon pipes in the industry.

Highlights

Composite carbon pipes were produced by applying prepreg fabric wrapping and autoclave curing methods together.

The mechanical and thermal properties of multi‐walled carbon nanotube (MWCNT) reinforced and unreinforced carbon composite pipes were investigated.

According to TGA, it was observed that the mass loss decreased.

Thermal decomposition temperature increased for MWCNT reinforced and unreinforced samples.

According to DMA, Tg of epoxy decreased for MWCNT unreinforced sample and increased for MWCNT reinforced sample.
Compliant composite elastomers via grafting short dangling chains for promoting thermal transport performance
Authors: Li Junhong , Pang Yunsong , Wang Jun , Yang Min , Zeng Xiaoliang , Ren Linlin , Sun Rong
Published: June 2024

The multifunctional composite elastomers serve as thermal interface materials for heat dissipation in electronic devices when their thermal transport performance is enhanced. The common method for enhancement, continuously raising the thermal conductive filler loading only can improve thermal conductivity of composite elastomers but reduces compliance, resulting in elevated contact thermal resistance with solid surfaces, compromising thermal transport. To address this, we propose grafting short dangling chains onto the composite elastomer matrix to further promote compliance under a certain filler loading. Characterization results demonstrate that the grafted chains effectively reduce relaxation time, enabling faster deformation for the material under pressure. This approach enhances interfacial compatibility, widening the thermal transport path at contact interfaces to contact thermal resistance by 94% (from 17.8 to 1.07 mm2W/K), significantly improving overall thermal transport. Additionally, we discussed the feasibility of employing composite elastomers as thermal interface materials for efficient chip heat dissipation.

Highlight

The grafted dangling chains can promote the composite elastomers softness.

The softness promotion can help reduce thermal contact resistance.

A series of theories are employed to learn the mechanisms of the promotion.

The resulting composite elastomers can be used as thermal interface materials.
Control of curing kinetic and strong interaction between resins network and boehmite nanoparticles: Dynamic‐mechanical and curing kinetics study
Authors: Rouhi Elham , Poorabdollah Mehdi , Bahrami Kiumars
Published: June 2024

In this study, two characteristics of boehmite nanoparticles (BNs) were used to improve the dynamic‐mechanical properties of pure unsaturated polyester resin (Neat UP). (1) Boehmite's ability to target free radical control in the radical curing reaction of UP resin, and (2) adsorption of alkyd chains and creation of attractive interactions with the resin network. X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FT‐IR), and field‐emission scanning electron microscopy (FESEM) analysis were used to identify the synthesis of particles. The results of FESEM analysis showed that the average particle size was 80–100 nm. TGA was used to investigate the thermal properties of the Neat UP and UP resin containing 0.3 wt% BNs (UP 0.3 BNs). The results of the dynamic‐mechanical analysis showed that the elastic modulus of the UP 0.3 BNs composite increased by 42% compared to the Neat UP. To investigate the significant increase observed in the dynamic‐mechanical properties, the curing kinetics were investigated by differential scanning calorimetry (DSC). Investigating the activation energy in terms of the conversion degree showed earlier dominance of the diffusion phenomenon in the UP 0.3 BNs composite. Investigating the diffusion factors provided by Vyazovkin–Sbirrazzouli showed a significant decrease in K and ED in the UP 0.3 BNs composite (−10.5, 19 kJ/mol) compared to the Neat UP resin (−9.5, 40 kJ/mol).

Highlights

Targeted control of free radicals increases network regularity of the UP/BNs.

Impressive improvement of mechanical properties of UP/BNs compared to Neat UP.

Increasing diffusion phenomenon dominance of UP/BNs system compared to Neat UP.
Investigation on the leakage resistance of metal‐fiber‐metal pressure vessel coupled with deformation
Authors: Zhang Dechao , Zhan Lihua , Zhao Dongwei , Zhao Shibo , Ma Bolin , Xiong Bang , Guo Jinzhan
Published: June 2024

This work focused on the leakage of the composite pressure vessel with a structure consisting of an aluminum alloy inner liner, a composite winding layer, and an aluminum covering. Through applying the finite element simulation approach and leakage rate test, it was found that the average strain of the winding layer in the lap region at the pressure of 46 MPa is 0.0078. Additionally, the leakage rate of the covering adhesive joint was investigated by considering the deformation, revealing that the leakage rate increases with increasing test pressure. The leakage rate at the lap region with a length of 18 mm is 2.05 × 10−7 Pa·m3/s at 0.0078 strain decreasing by 1.46 and 2.31 times compared to those under 12 and 7 mm lengths, respectively. The leakage rate exhibits a strict inverse correlation with the length of the leakage path under a pressure of 0 MPa. Additionally, when the deformation remains below the critical strain threshold (approximately 0.6%), the relationship between pressure and leakage rate shows a linear positive correlation. When the deformation of the component exceeds the critical strain threshold, the leakage rate of the component is significantly affected by its deformation and an increase in overall deformation results in a greater increase in leakage rate. The relationship between the two exhibits a non‐linear trend. This work provides strong technical support for the leakage assessment of composite pressure vessels.

Highlights

Deformation of the pressure vessel was analyzed through theoretical and simulation approaches.

Establishing the relationship between deformation and pressure in metal–metal lap structures.

Leakage analysis for different metal–metal lap lengths and deformation conditions.
Human management of ongoing evolutionary processes in agroecosystems
Authors: Mastretta‐Yanes Alicia , Tobin Daniel , Bellon Mauricio R. , von Wettberg Eric , Cibrián‐Jaramillo Angélica , Wegier Ana , Monroy‐Sais Ana Sofía , Gálvez‐Reyes Nancy , Ruiz‐Arocho Jorge , Chen Yolanda H.
Published: June 2024

Societal Impact Statement

Agricultural sustainability depends on the adaptation of crops to their local environment. Smallholder farmers who save seed provide an essential “evosystem” service by growing locally adapted seed varieties that can recruit biodiversity to enhance their growth and defense. While professional plant breeding has diverted evolutionary processes away from local adaptation, smallholder farmers, particularly those in centers of origin for crops, benefit society by selecting and propagating diverse crop varieties that allow local adaptation processes to perpetuate. Given that smallholders support society through the generation of evosystem services, changes in policy and practice are needed to support the livelihoods of smallholder farmers in ways that mitigate risk and recognize their important contributions to agricultural sustainability. To enhance the reach of this work, a Spanish language version of the paper is available in the Supporting Information (see Translation_ES). [Correction added on 18 June 2024, after first online publication: The preceding sentence has been added in this version.]

Long‐term food security and agricultural sustainability depend on protecting the eco‐evolutionary processes that select for local adaptation in crops. Since seed systems structure how people acquire seed, institutional and social changes influence evolutionary processes within agroecosystems. Since World War II, the rise of professional breeding has bifurcated seed systems into traditional and formal systems, which has negatively affected agrobiodiversity, crop evolution, and agricultural sustainability. In traditional seed systems, farmers often save seed from plants that best provide desired qualities, selecting landrace crop varieties to adapt to local environmental conditions. In formal or centralized seed systems, farmers buy seeds bred primarily for maximizing yield under ideal conditions. When farmers source seeds externally, evolutionary processes underlying local adaptation are disrupted. Here, we argue that traditional seed systems provide important evosystem services, or the evolutionary processes resulting from the maintenance and use of genetic diversity that benefit society. We present a framework on how seed systems influence the evolutionary processes that enable local adaptation, which is necessary for sustainable agriculture. We discuss how changes in human values underlying traditional and formal seed systems can alter evolutionary processes that underlie local adaptation. We conclude that developing policies that support people in managing ecological and evolutionary processes within seed systems is needed to address current and future challenges of global food security and agricultural sustainability.
Green Biosynthesis of Silver Nanoparticles Utilizing Monstera deliciosa Leaf Extract and Estimation of its Antimicrobial Characteristics
Authors: Shirsul Janvi , Tripathi Ambuj , Ankamwar Balaprasad
Published: June 2024

Herein, single step biosynthesis of silver nanoparticles (AgNPs) is reported by using AgNO3 and Monstera deliciosa (MD) leaf extract. Spherical AgNPs are obtained with difference in particle sizes and antibacterial activities using two sets of MD leaf extract having different heating periods 5 and 10 min. They are characterized by UV–vis spectroscopy, X‐ray diffraction (XRD), Zeta potential, Attenuated Total Reflectance Infrared Spectroscopy (ATR‐IR), and Field Emission Scanning Electron Microscopy (FE‐SEM). Dynamic Light Scattering (DLS) studies propose two types of AgNPs have hydrodynamic diameters of 104 and 80 nm. Nuclear Magnetic Resonance (NMR), Gas Chromatography‐Mass Spectrometry (GC‐MS), and High Resolution−Mass Spectrometry (HR‐MS) studies, which reveal the presence of various phytochemicals found in MD leaf extract. These biomolecules play a vital role as stabilizing and reducing agents to fabricate stable AgNPs. These AgNPs exhibit strong antibacterial activities having effective zone of inhibition for both Gram‐positive (Staphylococcus aureus, Bacillus subtilis) and Gram‐negative (Escherichia coli, Pseudomonas aeruginosa) microorganisms, nonetheless AgNPs against different fungi (Penicillium sp., Aspergillus flavus, Fusarium oxysporum, Rhizoctonia solani) show non‐antifungal characteristics because of their inert nature. This study suggests that AgNPs can be used in treating bacterial infections and drug delivery also for several therapeutic and diagnostic applications.
Experimental and Theoretical Investigation of Zr‐Doped CuO/Si Solar Cell
Authors: Yigit Gezgin Serap , Baturay Şilan , Ozaydin Cihat , Kilic Hamdi Sukur
Published: June 2024

Copper oxide (CuO) is a nanostructured semiconductor material with the potential for solar energy conversion and can be suitable for solar cells when used as a thin film. Herein, nondoped and doped (doping ratios of 1%, 2%, and 3% zirconium [Zr]) CuO thin films on silicon (Si) with the spin‐coating technique are developed. Optical and topological characterizations of CuO thin films are examined by ultraviolet‐visible and X‐ray diffraction. The electrical properties of nondoped and Zr‐doped CuO/Si heterojunctions are investigated with experimental current–voltage measurements in the dark and under illuminated conditions. The electrical behavior of nondoped and Zr‐doped CuO/Si heterojunctions is obtained using the experimental J–V technique and computational Cheung–Cheung and Norde methods. A simulation based on nondoped and Zr‐doped CuO/n‐Si heterojunction solar cells using SCAPS‐1D is completed. Photovoltaic (PV) parameters of experimentally produced and theoretically calculated CuO and Zr‐doped CuO/Si heterojunction solar cells are compared. Accordingly, PV parameters of 1% Zr‐doped CuO/Si solar cells show the highest power conversion efficiency calculated as a function of interfacial defect density and hole carrier concentration.
Ultrafast Laser Hyperdoped Black Silicon and Its Application in Photodetectors: A Review
Authors: Huang Song , Jin Xiaorong , Wu Qiang , Song Guanting , Cao Jiaxin , Zhou Xu , Jiang Haonan , Gao Weiqing , Xu Jingjun
Published: June 2024

Based on the ultrafast and extremely strong interaction between laser pulses and materials, ultrafast laser irradiation can break the solid solubility constraints and enable hyperdoping of impurities. This process overcomes the bandgap constraints of crystalline silicon, resulting in heightened absorption across a broad spectral range spanning from ultraviolet to infrared wavelengths, therefore commonly referred to as black silicon (b‐Si). The b‐Si demonstrates significant changes in optoelectronic properties, making it highly promising for applications in silicon photonics. Specifically, b‐Si photodetectors exhibit distinct advantages in terms of high photoelectric gain at low voltage, ultrabroadband spectral responsivity, large dynamic range, and suitability for operation over a wide temperature range. These properties address the limitations of traditional silicon photodetectors, showcasing great potential for applications in optoelectronic integration, artificial intelligence, information technology, energy devices, and beyond. This review focuses on b‐Si achieved through ultrafast laser processing, with a special emphasis on its applications in photodetectors. The mechanism of ultrafast laser irradiation and the properties of hyperdoped silicon are discussed. Then, the research progresses and state‐of‐the‐art b‐Si photodetectors are introduced, as well as working mechanism and potential application expansion. Finally, the development prospects of b‐Si photodetectors based on ultrafast laser hyperdoping are predicted.
Theoretical Study of Magnetization and Electrical Conductivity of Ion‐Doped KBiFe2O5 Nanoparticles
Authors: Apostolov Angel T. , Apostolova Iliana N. , Wesselinowa Julia M.
Published: June 2024

The electrical conductivity σ and magnetization M of (KBFO) nanoparticles (NPs) are systematically examined using a microscopic model and Green's function theory. KBFO is characterized by a narrow bandgap and relatively weak electrical conductivity σ, which presents a problem in carrier transportation and collection. Therefore, ways to enhance σ are found. The first is reducing the NP size. The second one is doping at the Fe and Bi sites with different ions which cause a compressive strain, that is, their ionic radius is smaller than that of the host ion. It is shown that doping with Al at the Fe site as well as with Ru or La ions at the Bi site leads to enhancing the electrical conductivity σ. The magnetization M increases with increasing concentration of all dopants.
The role of identification in data‐driven policy iteration: A system theoretic study
Authors: Song Bowen , Iannelli Andrea
Published: June 2024

The goal of this article is to study fundamental mechanisms behind so‐called indirect and direct data‐driven control for unknown systems. Specifically, we consider policy iteration applied to the linear quadratic regulator problem. Two iterative procedures, where data collected from the system are repeatedly used to compute new estimates of the desired optimal controller, are considered. In indirect policy iteration, data are used to obtain an updated model estimate through a recursive identification scheme, which is used in a certainty‐equivalent fashion to perform the classic policy iteration update. By casting the concurrent model identification and control design as a feedback interconnection between two algorithmic systems, we provide a closed‐loop analysis that shows convergence and robustness properties for arbitrary levels of excitation in the data. In direct policy iteration, data are used to approximate the value function and design the associated controller without requiring the intermediate identification step. After proposing an extension to a recently proposed scheme that overcomes potential identifiability issues, we establish under which conditions this procedure is guaranteed to deliver the optimal controller. Based on these analyses we are able to compare the strengths and limitations of the two approaches, highlighting aspects such as the required samples, convergence properties, and excitation requirement. Simulations are also provided to illustrate the results.
UP‐GAN: Channel‐spatial attention‐based progressive generative adversarial network for underwater image enhancement
Authors: Wang Ning , Chen Yanzheng , Wei Yi , Chen Tingkai , Karimi Hamid Reza
Published: June 2024

Focusing on severe color deviation, low brightness, and mixed noise caused by inherent scattering and light attenuation effects within underwater environments, an underwater‐attention progressive generative adversarial network (UP‐GAN) is innovated for underwater image enhancement (UIE). Salient contributions are as follows: (1) By elaborately devising an underwater background light estimation module via an underwater imaging model, the degradation mechanism can be sufficiently integrated to fuse prior information, which in turn saves computational burden on subsequent enhancement; (2) to suppress mixed noise and enhance foreground, simultaneously, an underwater dual‐attention module is created to fertilize skip connection from channel and spatial aspects, thereby getting rid of noise amplification within the UIE; and (3) by systematically combining with spatial consistency, exposure control, color constancy, color relative dispersion losses, the entire UP‐GAN framework is skillfully optimized by taking into account multidegradation factors. Comprehensive experiments conducted on the UIEB data set demonstrate the effectiveness and superiority of the proposed UP‐GAN in terms of both subjective and objective aspects.
Heterogeneous Integration of Memristive and Piezoresistive MDMO‐PPV‐Based Copolymers in Nociceptive Transmission with Fast and Slow Pain for an Artificial Pain‐Perceptual System
Authors: Tsao Shih‐Cheng , Chang Kuo‐Hsuan , Fu Yi , Tai Han‐Hsiang , Lin Ting‐Han , Wu Ming‐Chung , Wang Jer‐Chyi
Published: June 2024

Nociceptive pain perception is a remarkable capability of organisms to be aware of environmental changes and avoid injury, which can be accomplished by specialized pain receptors known as nociceptors with 4 vital properties including threshold, no adaptation, relaxation, and sensitization. Bioinspired systems designed using artificial devices are investigated to imitate the efficacy and functionality of nociceptive transmission. Here, an artificial pain‐perceptual system (APPS) with a homogeneous material and heterogeneous integration is proposed to emulate the behavior of fast and slow pain in nociceptive transmission. Retention‐differentiated poly[2‐methoxy‐5‐(3,7‐dimethyoctyoxyl)‐1,4‐phenylenevinylene] (MDMO‐PPV) memristors with film thicknesses of 160 and 80 nm are manufactured and adopted as A‐δ and C nerve fibers of nociceptor conduits, respectively. Additionally, a nociceptor mimic, the ruthenium nanoparticles (Ru‐NPs)‐doped MDMO‐PPV piezoresistive pressure sensor, is fabricated with a noxiously stimulated threshold of 150 kPa. Under the application of pricking and dull noxious stimuli, the current flows predominantly through the memristor to mimic the behavior of fast and slow pain, respectively, in nociceptive transmission with postsynaptic potentiation properties, which is analogous to biological pain perception. The proposed APPS can provide potential advancements in establishing the nervous system, thus enabling the successful development of next‐generation neurorobotics, neuroprosthetics, and precision medicine.
Space‐Confined Growth for Thickness‐Controlled Cs3Bi2I9 Perovskite Single Crystal Wafers for X‐Ray Detectors
Authors: Yang Manman , Wu Xiaoling , Li Anfeng , Hao Xia , Wu Lili , Tian Haibo , Yang Dingyu , Zhang Jingquan
Published: June 2024

The Cs3Bi2I9 single crystal, as an all‐inorganic non‐lead perovskite, offers advantages such as stability and environmental friendliness. Its superior photoelectric properties, attributed to the absence of grain boundary influence, make it an outstanding X‐ray detection material compared to polycrystals. In addition to material properties, X‐ray detector performance is affected by the thickness of the absorption layer. Addressing this, a space‐confined method is proposed. The temperature field is determined through finite element simulation, effectively guiding the design of the space‐confined method. Through this innovative method, a series of thickness‐controlled perovskite single crystal wafers (PSCWs) are successfully prepared. Corresponding X‐ray detectors are then prepared, and the impact of single crystal thickness on device performance is investigated. With an increase in single crystal thickness, a rise followed by a decline in device sensitivity is observed, reaching an optimal value at 0.7 mm thickness at 40V mm−1 with a device performance of 11313.6µC Gy−1 cm−2. This space‐confined method enables the direct growth of high‐quality perovskite single crystals with specified thickness, eliminating the need for slicing or etching.
Spiky Magnetic Microparticles Synthesized from Microrod‐Stabilized Pickering Emulsion
Authors: Mu Yijiang , Tran Hong‐Huy , Xiang Zhenting , Majumder Anirban , Hsu Emery , Steager Edward , Koo Hyun , Lee Daeyeon
Published: June 2024

Tailoring the microstructure of magnetic microparticles is of vital importance for their applications. Spiky magnetic particles, such as those made from sunflower pollens, have shown promise in single cell treatment and biofilm removal. Synthetic methods that can replicate or extend the functionality of such spiky particles would be advantageous for their widespread utilization. In this work, a wet‐chemical method is introduced for spiky magnetic particles that are templated from microrod‐stabilized Pickering emulsions. The spiky morphology is generated by the upright attachment of silica microrods at the oil‐water interface of oil droplets. Spiky magnetic microparticles with control over the length of the spikes are obtained by dispersing hydrophobic magnetic nanoparticles in the oil phase and photopolymerizing the monomer. The spiky morphology dramatically enhances colloidal stability of these particles in high ionic strength solutions and physiologic media such as human saliva and saline‐based biofilm suspension. To demonstrate their utility, the spiky magnetic particles are applied for magnetically controlled removal of oral biofilms and retrieval of bacteria for diagnostic sampling. This method expands the toolbox for engineering microparticle morphology and could promote the fabrication of functional magnetic microrobots.
Insightful Understanding of Synergistic Oxygen Reduction on PtCo3(111) Toward Zinc‐Air Batteries
Authors: Chen Xiangxiong , Guo Jiangnan , Qian Dong , Wu Jiayun , Liao Weixiong , Waterhouse Geoffrey I. N. , Liu Jinlong
Published: June 2024

Theory‐guided materials design is an effective strategy for designing catalysts with high intrinsic activity whilst minimizing the usage of expensive metals like platinum. As proof‐of‐concept, herein it demonstrates that using density functional theory (DFT) calculations and experimental validation that intermetallic PtCo3 alloy nanoparticles offer enhanced electrocatatalytic performance for the oxygen reduction reaction (ORR) compared to Pt nanoparticles. DFT calculations established that PtCo3(111) surfaces possess better intrinsic ORR activity compared to Pt(111) surfaces, owing to the synergistic action of adjacent Pt and Co active sites which optimizes the binding strength of ORR intermediates to boost overall ORR kinetics. With this understanding, a PtCo3/NC catalyst, comprising PtCo3 nanoparticles exposing predominantly (111) facets dispersed on an N‐doped carbon support, is successfully fabricated. PtCo3/NC demonstrates a high specific activity (3.4 mA cm−2 mgPt−1), mass activity (0.67 A mgPt−1), and cycling stability for the ORR in 0.1 M KOH, significantly outperforming a commercial 20 wt.% Pt/C catalyst. Moreover, a zinc‐air battery (ZAB) assembled with PtCo3/NC as the air‐electrode catalyst delivered an open‐circuit voltage of 1.47 V, a specific capacity of 775.1 mAh gZn−1 and excellent operation durability after 200 discharge/charge cycles, vastly superior performance to a ZAB built using commercial Pt/C+IrO2 as the air‐electrode catalyst.