bluuebunny/crossref_metadata_2025 huggingface dataset:
Managing the Knowledge Deficit in the German Automotive Industry
Authors: Felser Kerstin , Wynn Martin
Published: April 2023

The combined effects of decarbonization and digitalization have had a significant impact on the German automotive industry, with different business models emerging that often involve new business alliances with other automotive companies and technology companies. This rapid and dramatic change momentum has resulted in a “knowledge deficit” in the industry, as regards the skills and know-how required to operate successfully in the digital economy. Using an inductive, qualitative research methodology, based on in-depth interviews with industry experts and practitioners, this article identifies the main areas in which skills, knowledge and competencies are lacking, and assesses the main ways in which the industry is trying to address the problem. A number of emergent issues are also discussed. The article finds that many years of technology outsourcing have left the industry deficient in core technology skills for software development, data management and architecture design, and that new competencies in cybersecurity, platforms and ecosystems, and sourcing management are also urgently needed. The industry is addressing this challenge through a combination of strategies, including major partnership arrangements with the big tech companies. The article concludes that entrepreneurial innovation and radical digital leadership will be required to adequately address the knowledge deficit in the digital era.
Combining Fuzzy, Multicriteria and Mapping Techniques to Assess Soil Fertility for Agricultural Development: A Case Study of Firozabad District, Uttar Pradesh, India
Authors: Saraswat Anuj , Ram Shri , AbdelRahman Mohamed A. E. , Raza Md Basit , Golui Debasis , HC Hombegowda , Lawate Pramod , Sharma Sonal , Dash Amit Kumar , Scopa Antonio , Rahman Mohammad Mahmudur
Published: April 2023

Soil fertility (SF) assessment is an important strategy for identifying agriculturally productive lands, particularly in areas that are vulnerable to climate change. This research focuses on detecting SF zones in Firozabad district, Uttar Pradesh, India, for agricultural purposes, so that they can be prioritized for future management using the fuzzy technique in the Arc GIS model-builder. The model computing technique was also deployed to determine the different fertility zones, considering 17 soil parameters. The derived fuzzy technique outperformed the traditional method of dividing the sampling sites into clusters to correlate soil fertility classes with the studied soil samples. The prioritization of the soil factors and a spatial analysis of the fertility areas were carried out using the Analytic Hierarchy Process (AHP) and GIS tools, respectively. The AHP analysis outcome indicated that hydraulic properties had the highest weighted value, followed by physical and chemical properties, regarding their influence on SF. The spatial distribution map of physico-chemical properties also clearly depicts the standard classification. A fuzzy priority map was implemented based on all the classes parameters to identify the five fertility classes of the soil, namely very high (0.05%); high (16.59%); medium (60.94%); low (22.34%); and very low (0.07% of total area). This study will be of significant value to planners and policymakers in the future planning and development of activities and schemes that aim to solve similar problems across the country.
Spatial Layout Analysis and Evaluation of Electric Vehicle Charging Infrastructure in Chongqing
Authors: Wang Zixuan , Yang Qingyuan , Wang Chuwen , Wang Lanxi
Published: April 2023

This study considers the spatial analysis and evaluation layout of electric vehicle charging infrastructures, taking the central urban area of Chongqing as an example. Mathematical model analysis, ArcGIS spatial analysis, field investigation, questionnaire measurement, and hierarchical analysis methods are utilized to discuss the current distribution characteristics and supply–demand matching of the electric vehicle charging infrastructure in this region. The resulting data can provide references for the optimal layout of charging infrastructure. The main conclusions of this study are as follows: (1) The configuration and demand of charging infrastructure in the central urban area of Chongqing have obvious spatial differentiation and show strong centrality. (2) It is a common phenomenon that the charging infrastructure in the central urban area of Chongqing is in short supply, and it is pressing that a new charging infrastructure be built. (3) In the process of construction and operation of charging infrastructure, various factors, such as economy and traffic, should be comprehensively considered; at the same time, incidents of inefficient operation, such as being crowded out by nonelectric vehicles and unmaintained facility failure, should be minimized.
Utilization Quality Evaluation and Barrier Factor Diagnosis of Rural Residential Areas in Agricultural Regions of the Northeast Plain: A Case Study of Wangkui County, Heilongjiang Province, China
Authors: Zhang Hui , Cong Rong , Luan Siyu
Published: April 2023

Conducting quality evaluations of rural residential areas and effectively improving their utilization levels is an important aspect of correctly handling the relationship between humans and the land and achieving high-quality rural developments. Taking Wangkui County, Heilongjiang Province, as an example, this study aimed to achieve the “intensive, humanistic, and green” development of rural residential areas. An evaluation index system of utilization quality was constructed using three aspects: intensive land utilization, human settlement environment quality, and ecological environment quality. The comprehensive evaluation results were classified using a multidimensional combination matrix and targeted optimization plans were proposed. Additionally, an obstacle diagnosis model was constructed to identify the factors that hinder the high-quality utilization of rural residential areas. The results demonstrated the following: (1) The utilization quality of the rural residential areas in the study area was mainly at a medium level, followed by low and high levels, with proportions of 20.18%, 51.38%, and 28.44%, respectively. The utilization levels gradually decreased from the town centers to the surrounding areas. (2) Based on the evaluation results, there were 23 combinations of rural residential areas in the study area, which were classified into four types: coordinated control, key development, single leading, and transforming and upgrading. Optimization plans were proposed for the different types. (3) From the perspective of identifying the barrier factors, the top five factors that hindered the high-quality utilization of rural residential areas were the traffic land density, aggregation index, green-coverage rate of built-up areas, completeness of public service facilities, and the proportion of secondary and tertiary industrial land area. This study provides a significant reference for the evaluation of the utilization quality of rural residential areas in plain agricultural regions to effectively raise their levels of intensive land utilization, improve their settlement environments, enhance their ecological quality, and achieve a development of high quality.
Analysis of Modified Finite Length Journal Bearing under Position Perturbation
Authors: Jamali Hazim U. , Sultan Hakim S. , Abdullah Oday I. , Jameel Al-Tamimi Adnan Naji , Al-Masoudy Murtadha M. , Ruggiero Alessandro , Valigi Maria Cristina
Published: April 2023

The performance of journal bearings is significantly affected by the presence of misalignment, which is usually an accompanying problem for this type of bearing. This includes exceeding the design limits for the maximum pressure and the minimum film thickness levels, which affect, in other words, the load-carrying capacity of the system. In addition, it raises the possibility of increasing the wear rate at the bearing edges and increases the friction coefficient at high levels of misalignment. This paper deals with the problem of finite-length misaligned journal bearings, considering a novel comparison between two cases of misalignments: the general 3D misalignment and the vertical misalignment problems for modified bearings. The effect of introducing a variable axial bearing profile on the bearing characteristics and the time responses of the rotor bearing system under position perturbation has also been investigated. The numerical solution of this hydrodynamic problem is based on the finite difference method using Reynolds boundary conditions method. Results show that using a variable bearing profile improves bearing characteristics, such as increasing the minimum film thickness significantly and reducing the pressure levels in addition to reducing the friction coefficient. Furthermore, the modification enhances the rotor-bearing stability under position perturbation, extending the speed range for a safe operation.
Corrosion Inhibitors: Natural and Synthetic Organic Inhibitors
Authors: Al-Amiery Ahmed A. , Isahak Wan Nor Roslam Wan , Al-Azzawi Waleed Khalid
Published: April 2023

Corrosion is a major challenge in various industries and can cause significant damage to metal structures. Organic corrosion inhibitors are compounds that are used to reduce or prevent corrosion by forming a protective film on metal surfaces. The present review article focuses on natural and synthetic organic corrosion inhibitors and their classifications, active functional groups, and efficiency estimations. Furthermore, previous studies on the use of natural and synthetic organic inhibitors are discussed, along with adsorption isotherms and mechanisms of organic corrosion inhibitors. The kinetics of corrosion modeling are also discussed, providing insights into the effectiveness of organic inhibitors at reducing corrosion. This review aims to provide a comprehensive overview of the current knowledge on organic corrosion inhibitors, with the aim of promoting their wider use in corrosion protection.
Regioselectivity Amination of Usnic Acid by Ammonia in Water
Authors: Filimonov Aleksandr , Luzina Olga , Gatilov Yuri , Salakhutdinov Nariman
Published: April 2023

Usnic acid is a well-known secondary lichen metabolite exhibiting a broad spectrum of biological activity. Previously it was shown that the reaction of usnic acid with various amines resulted in enamine-bond formation instead of the C(11)=O carbonyl group. Enamines obtained have a pronounced biological activity. In this work, we have shown that the reaction of usnic acid with ammonia can be regioselective if the solvent is replaced by water. The regioselectivity of that reaction depends on temperature and ammonia quantity. The C-1 enamine as only product formation has been obtained by the usnic acid reaction with an excess of ammonia (20 eq.) in water with cooling (+9 °C).
Processing and Physicochemical Properties of Magnetite Nanoparticles Coated with Curcuma longa L. Extract
Authors: Alvarado-Noguez Margarita L. , Matías-Reyes Ana E. , Pérez-González Mario , Tomás Sergio A. , Hernández-Aguilar Claudia , Domínguez-Pacheco Flavio A. , Arenas-Alatorre Jesús A. , Cruz-Orea Alfredo , Carbajal-Tinoco Mauricio D. , Galot-Linaldi Jairo , Estrada-Muñiz Elizabet , Vega-Loyo Libia , Santoyo-Salazar Jaime
Published: April 2023

In this work, Curcuma longa L. extract has been used in the synthesis and direct coating of magnetite (Fe3O4) nanoparticles ~12 nm, providing a surface layer of polyphenol groups (–OH and –COOH). This contributes to the development of nanocarriers and triggers different bio-applications. Curcuma longa L. is part of the ginger family (Zingiberaceae); the extracts of this plant contain a polyphenol structure compound, and it has an affinity to be linked to Fe ions. The nanoparticles’ magnetization obtained corresponded to close hysteresis loop Ms = 8.81 emu/g, coercive field Hc = 26.67 Oe, and low remanence energy as iron oxide superparamagnetic nanoparticles (SPIONs). Furthermore, the synthesized nanoparticles (G-M@T) showed tunable single magnetic domain interactions with uniaxial anisotropy as addressable cores at 90–180°. Surface analysis revealed characteristic peaks of Fe 2p, O 1s, and C 1s. From the last one, it was possible to obtain the C–O, C=O, –OH bonds, achieving an acceptable connection with the HepG2 cell line. The G-M@T nanoparticles do not induce cell toxicity in human peripheral blood mononuclear cells or HepG2 cells in vitro, but they can increase the mitochondrial and lysosomal activity in HepG2 cells, probably related to an apoptotic cell death induction or to a stress response due to the high concentration of iron within the cell.
Ablation Characteristics Research in Solid Rocket Motor’s Combustion Chamber Produced by 3D Printing
Authors: Hui Weihua , Hu Yun , Liu Yang , Cai Qiang , Zhao Weijie
Published: April 2023

A polyamide 12(PA12) reinforced with glass beads (GBs) solid rocket motor (SRM) produced by 3D Printing is proposed in the paper. The ablation research of the combustion chamber is studied by simulating the motor’s operating environment through ablation experiments. The results show that the maximum ablation rate for the motor was 0.22 mm/s, which occurred at the location where the combustion chamber meets the baffle. The closer to the nozzle, the greater its ablation rate. Through the microscopic appearance analysis of the composite material from the inner wall surface to the outer wall surface in several directions before and after the ablation experiments, it was found that the GBs with weak or no interfacial adhesion to PA12 may make the mechanical properties of the material degrade. The ablated motor had a large number of holes and some deposits on the inner wall surface. Also by evaluating the surface chemistry of the material, it was found that the composite material underwent thermal decomposition. Moreover, it underwent a complex chemical reaction with the propellant.
Determination of Trace Thorium and Uranium Impurities in Scandium with High Matrix by ICP-OES
Authors: She Zhixuan , Li Minglai , Feng Zongyu , Xu Yang , Wang Meng , Pan Xijuan , Yang Zhiqing
Published: April 2023

High-purity scandium oxide is the principal raw material of high-purity scandium metal and aluminum scandium alloy targets for electronic materials. The performance of electronic materials will be significantly impacted by the presence of trace amounts of radionuclides due to the increase in free electrons. However, about 10 ppm of Th and 0.5–20 ppm of U are typically present in commercially available high-purity scandium oxide, which it is highly necessary to remove. It is currently challenging to detect trace impurities in high-purity scandium oxide, and the detection range of trace thorium and uranium is relatively high. Therefore, it is crucial to develop a technique that can accurately detect trace Th and U in high concentrations of scandium solution in the research on high-purity scandium oxide quality detection and the removal of trace impurities. This paper adopted some advantageous initiatives to develop a method for the inductively coupled plasma optical emission spectrometry (ICP-OES) determination of Th and U in high-concentration scandium solutions, such as spectral line selection, matrix influence analysis, and spiked recovery. The reliability of the method was verified. The relative standard deviations (RSD) of Th is less than 0.4%, and the RSD of U is less than 3%, indicating that this method has good stability and high precision. This method can be used for the accurate determination of trace Th and U in high Sc matrix samples, which provides an effective technical support for the preparation of high purity scandium oxide, and supports the production of high-purity scandium oxide.
Microstructure Formation and Mechanical Properties of Metastable Titanium-Based Gradient Coating Fabricated via Intense Pulse Ion Beam Melt Mixing
Authors: Xu Mofei , Yu Xiang , Zhang Shijian , Yan Sha , Tarbokov Vladislav , Remnev Gennady , Le Xiaoyun
Published: April 2023

The unique flash heating characteristics of intense pulsed ion beams (IPIB) offer potential advantages to fabricate high-performance coatings with non-equilibrium structures. In this study, titanium-chromium (Ti-Cr) alloy coatings are prepared through magnetron sputtering and successive IPIB irradiation, and the feasibility of IPIB melt mixing (IPIBMM) for a film-substrate system is verified via finite elements analysis. The experimental results reveal that the melting depth is 1.15 μm under IPIB irradiation, which is in close agreement with the calculation value (1.18 μm). The film and substrate form a Ti-Cr alloy coating by IPIBMM. The coating has a continuous gradient composition distribution, metallurgically bonding on the Ti substrate via IPIBMM. Increasing the IPIB pulse number leads to more complete element mixing and the elimination of surface cracks and craters. Additionally, the IPIB irradiation induces the formation of supersaturated solid solutions, lattice transition, and preferred orientation change, contributing to an increase in hardness and a decrease in elastic modulus with continuous irradiation. Notably, the coating treated with 20 pulses demonstrates a remarkable hardness (4.8 GPa), more than twice that of pure Ti, and a lower elastic modulus (100.3 GPa), 20% less than that of pure Ti. The analysis of the load-displacement curves and H-E ratios indicates that the Ti-Cr alloy coated samples exhibit better plasticity and wear resistance compared to pure Ti. Specifically, the coating formed after 20 pulses exhibits exceptional wear resistance, as demonstrated by its H3/E2 value being 14 times higher than that of pure Ti. This development provides an efficient and eco-friendly method for designing robust-adhesion coatings with specific structures, which can be extended to various bi- or multi-element material systems.
Ultra-Translucent Zirconia Laminate Veneers: The Influence of Restoration Thickness and Stump Tooth-Shade
Authors: Mekled Salwa , Elwazeer Salma , Jurado Carlos A. , White James , Faddoul Faddy , Afrashtehfar Kelvin I. , Fischer Nicholas G.
Published: April 2023

This in vitro study aimed to evaluate the final shade of translucent zirconia laminate veneers with varying thicknesses over teeth with different shades. Seventy-five chairside computer-aided design/computer-aided manufacturing (CAD/CAM) shade A1 third-generation zirconia dental veneers, with thicknesses of 0.50 mm, 0.75 mm, and 1.00 mm, were placed on resin composite teeth with shades ranging from A1 to A4. The laminate veneers were divided into groups based on thickness and background shade. All restorations were evaluated with a color imaging spectrophotometer, to map the veneer surface from A1 to D4. Regardless of the thickness or background shade, all dental veneers showed color alteration from the original shade. Veneers with 0.5 mm thickness tended to display the B1 shade, while veneers with 0.75 mm and 1.0 mm thickness primarily exhibited the B2 shade. The thickness of the laminate veneer and background shade significantly modified the original shade of the zirconia veneer. One-way analysis of variance was performed and a Kruskal–Wallis test was used to determine the significance between the three veneer thicknesses groups. The results indicated that the thinner restorations showed higher values with the color imaging spectrophotometer, suggesting that thinner veneers may result in more consistent color matching. This study underscores the importance of carefully considering thickness and background shade when selecting zirconia laminate veneers, to ensure optimal color matching and overall aesthetic outcomes.
Lead-Free Ternary Glass for Radiation Protection: Composition and Performance Evaluation for Solar Cell Coverage
Authors: Uosif Mohamed A. M. , Issa Shams A. M. , Ene Antoaneta , Mostafa Ahmed M. A. , Atta Ali , El Agammy Emam F. , Zakaly Hesham M. H.
Published: April 2023

Solar cells in superstrate arrangement need a protective cover glass as one of its main components. The effectiveness of these cells is determined by the cover glass’s low weight, radiation resistance, optical clarity, and structural integrity. Damage to the cell covers brought on by exposure to UV irradiation and energetic radiation is thought to be the root cause of the ongoing issue of a reduction in the amount of electricity that can be generated by solar panels installed on spacecraft. Lead-free glasses made of xBi2O3–(40 − x)CaO-60P2O5 (x = 5, 10, 15, 20, 25, and 30 mol%) were created using the usual approach of melting at a high temperature. The amorphous nature of the glass samples was confirmed using X-ray diffraction. At energies of 81, 238, 356, 662, 911, 1173, 1332, and 2614 keV, the impact of various chemical compositions on gamma shielding in a phospho-bismuth glass structure was measured. The evaluation of gamma shielding revealed that the results of the mass attenuation coefficient of glasses increase as the Bi2O3 content increases but decrease as the photon energy increases. As a result of the study conducted on the radiation-deflecting properties of ternary glass, a lead-free low-melting phosphate glass that exhibited outstanding overall performance was developed, and the optimal composition of a glass sample was identified. The 60P2O5–30Bi2O3–10CaO glass combination is a viable option for use in radiation shielding that does not include lead.
Densification Behavior and Build Quality of Duplex Stainless Steel Fabricated by Laser Powder Bed Fusion
Authors: Xiang Hongliang , Chen Guanglei , Zhao Wei , Wu Chaochao
Published: April 2023

A systematic study on the densification behavior and build quality of 2205 duplex stainless steel fabricated using laser powder bed fusion (LPBF) was performed by experiment and simulation, aiming to offer some supplementary work for research on additive manufacturing (AM) of duplex stainless steel. In this study, samples with differing laser powers were prepared, and a highest relative density of 98.87% was obtained. Then, the pore defects and surface morphologies were investigated to unveil densification behaviors during a building process. The relationship between surface morphologies and the formation of pores was discussed. It reveals that the inter-layer printing on these surface defects caused by unreasonable laser power could increase the possibility of inside pore defects and reduce the density of specimens. Particularly, the big spatters could be the cause of lack-of-fusion defects even under sufficient power input. Therefore, adequate intra- and inter-layer bonding under reasonable processing parameters is crucial for densification. The mechanical properties of the specimens prepared with the laser power of 260 W are the highest, and the yield strength, tensile strength, and elongation are 798.68 MPa, 953.63 MPa, and 10.85%, respectively.
Effect of Preload on Tensile Fracture of Variable Cross-Section Bolts: Experiment and Simulation
Authors: Yao Shuguang , Zhang Meng
Published: April 2023

High-strength bolts are widely used in structural connections, and the preload affects the failure behavior of bolts. In this paper, a variable cross-section bolt (VCSB) with weakened strength to induce fracture is designed. Quasi-static tensile experiments with different preload torque values were performed on the VCSB. The preload torques of 0, 430, 610, and 820 N·m were applied to the VCSB connection structures before the test. The load–displacement curves obtained by the test could be divided into three stages: the initial elastic phase, the yield phase, and the rapidly necking phase. As the preload increased, the stiffness of the initial elastic phase increased from 101.21 kN/mm to 270.64 kN/mm and the fracture displacement DC decreased from 10.54 mm to 8.42 mm. Finite element models were developed to simulate the failure process of VCSB under tensile loads. The difference between the FB and DC values in the simulation results and the test is within 2%. The simulations were carried out by adjusting the prestress from 0 to 650 MPa. The results show that the value of preload force has no effect on the FB of VCSB, but greatly influences the DC and FC of the connection.
Metabolic Acidosis Results in Sexually Dimorphic Response in the Heart Tissue
Authors: Liu Yamin , Atiq Amina , Peterson Anna , Moody Mikayla , Novin Ashkan , Deymier Alix C. , Afzal Junaid , Kshitiz
Published: April 2023

Metabolic acidosis (MA) is a highly prevalent disorder in a significant proportion of the population, resulting from imbalance in blood pH homeostasis. The heart, being an organ with very low regenerative capacity and high metabolic activity, is vulnerable to chronic, although low-grade, MA. To systematically characterize the effect of low-grade MA on the heart, we treated male and female mice with NH4Cl supplementation for 2 weeks and analyzed their blood chemistry and transcriptomic signature of the heart tissue. The reduction of pH and plasma bicarbonate levels without an associated change in anion gap indicated a physiological manifestation of low-grade MA with minimal respiratory compensation. On transcriptomic analysis, we observed changes in cardiac-specific genes with significant gender-based differences due to MA. We found many genes contributing to dilated cardiomyopathy to be altered in males, more than in females, while cardiac contractility and Na/K/ATPase-Src signaling were affected in the opposite way. Our model presents a systems-level understanding of how the cardiovascular tissue is affected by MA. As low-grade MA is a common ailment with many dietary and pharmaceutical interventions, our work presents avenues to limit chronic cardiac damage and disease manifestation, as well as highlighting the sex differences in MA-induced cardiovascular damage.
Zircon U–Pb Geochronology, Geochemistry and Geological Significance of the Santaishan–Yingjiang Ultramafic Rocks in Western Yunnan, China
Authors: Liu Huimin , Chen Yongqing , Shang Zhi
Published: April 2023

The study of ultramafic rocks in Western Yunnan is of great significance for an understanding of the tectonic evolution of the Neo-Tethys Ocean. The zircon U–Pb data indicated that the Santaishan serpentinized pyroxene peridotite (SSPP) was formed 186–190 Ma, and the Yingjiang hornblende pyroxenite (YHP) was formed 182–183 Ma. The content of MgO in the SSPP is relatively high, but the SiO2, Al2O3, CaO and TiO2 content and ΣREE are low, while the YHP has opposite characteristics. The samples from the SSPP and YHP have similar distribution patterns of trace elements, both being enriched in large ion lithophile elements (LILEs) such as Rb, Ba and Th and depleted in high field strength elements (HFSEs) such as Ti, P and Nb. These characteristics are consistent with the supra-subduction zone (SSZ) type and mid-ocean ridge basalt (MORB) type of ophiolite in the Bangong–Nujiang suture zone. The SSPP rocks have relatively high (87Sr/86Sr)i ratios (0.7091–0.7131) and positive Hf(t) values (11.2–13.8), with εNd(t) values varying from −1.1 to 9.4. The YHP has relatively low εHf(t) values (3.5 to 6.9), with the Nd–Hf isotopic model ages ranging from 610 to 942 Ma. The signatures of Sr–Nd and Lu–Hf isotopes indicate that the SSPP and YHP were derived from the depleted mantle, and the crustal material in the magma source may have originated from the Neoproterozoic Rodinia supercontinent. In the early Middle Jurassic (190 Ma), the Tengchong Block was in the setting of an active continental margin induced by the subduction of the Bangong–Nujiang Ocean, where the SSZ-type SSPP with ophiolite characteristics was formed. With the continuous subduction of the Bangong–Nujiang Ocean, the slab retreated and induced mantle convection, which resulted in the gradual thinning of the continental crust. Meanwhile, the Yingjiang back-arc basin was formed 183 Ma. Under the influence of the upwelling of the asthenosphere and the mixture of crustal materials, the MORB-type YHP was formed.
Optoelectronic Properties of a Cylindrical Core/Shell Nanowire: Effect of Quantum Confinement and Magnetic Field
Authors: El-Yadri Mohamed , El Hamdaoui Jawad , Aghoutane Noreddine , Pérez Laura M. , Baskoutas Sotirios , Laroze David , Díaz Pablo , Feddi El Mustapha
Published: April 2023

This study investigates the effect of quantum size and an external magnetic field on the optoelectronic properties of a cylindrical AlxGa1−xAs/GaAs-based core/shell nanowire. We used the one-band effective mass model to describe the Hamiltonian of an interacting electron-donor impurity system and employed two numerical methods to calculate the ground state energies: the variational and finite element methods. With the finite confinement barrier at the interface between the core and the shell, the cylindrical symmetry of the system revealed proper transcendental equations, leading to the concept of the threshold core radius. Our results show that the optoelectronic properties of the structure strongly depend on core/shell sizes and the strength of the external magnetic field. We found that the maximum probability of finding the electron occurs in either the core or the shell region, depending on the value of the threshold core radius. This threshold radius separates two regions where physical behaviors undergo changes and the applied magnetic field acts as an additional confinement.
Towards a CdTe Solar Cell Efficiency Promotion: The Role of ZnO:Al and CuSCN Nanolayers
Authors: Montoya De Los Santos Isaac , Pérez-Orozco Alan A. , Liña-Martínez Diego A. , Courel Maykel , Meza-Avendaño Carlos A. , Borrego-Pérez Jorge A. , Pérez Laura M. , Laroze David
Published: April 2023

A numerical simulation is a valuable tool since it allows the optimization of both time and the cost of experimental processes for time optimization and the cost of experimental processes. In addition, it will enable the interpretation of developed measurements in complex structures, the design and optimization of solar cells, and the prediction of the optimal parameters that contribute to manufacturing a device with the best performance. In this sense, a detailed simulation study was carried out in this work by the Solar Cell Capacitance Simulator (SCAPS). In particular, we evaluate the influence of absorber and buffer thickness, absorber defect density, work function in back contact, Rs, Rsh, and carrier concentration on a CdTe/CdS cell to maximize its performance. Furthermore, the incorporation effect of ZnO:Al (TCO) and CuSCN (HTL) nanolayers was studied for the first time. As a result, the efficiency of the solar cell was maximized from 16.04% to 17.74% by increasing the Jsc and Voc. This work will play an essential role in enhancing the performance of CdTe-based devices with the best performance.
Intercalation Effects on the Dielectric Properties of PVDF/Ti3C2Tx MXene Nanocomposites
Authors: Tsyganov Alexey , Vikulova Maria , Artyukhov Denis , Zheleznov Denis , Gorokhovsky Alexander , Gorshkov Nikolay
Published: April 2023

In this study, we report the effect of intercalation of dimethyl sulfoxide (DMSO) and urea molecules into the interlayer space of Ti3C2Tx MXene on the dielectric properties of poly(vinylidene fluoride) (PVDF)/MXene polymer nanocomposites. MXenes were obtained by a simple hydrothermal method using Ti3AlC2 and a mixture of HCl and KF, and they were then intercalated with DMSO and urea molecules to improve the exfoliation of the layers. Then, nanocomposites based on a PVDF matrix loading of 5–30 wt.% MXene were fabricated by hot pressing. The powders and nanocomposites obtained were characterized by using XRD, FTIR, and SEM. The dielectric properties of the nanocomposites were studied by impedance spectroscopy in the frequency range of 102–106 Hz. As a result, the intercalation of MXene with urea molecules made it possible to increase the permittivity from 22 to 27 and to slightly decrease the dielectric loss tangent at a filler loading of 25 wt.% and a frequency of 1 kHz. The intercalation of MXene with DMSO molecules made it possible to achieve an increase in the permittivity up to 30 at a MXene loading of 25 wt.%, but the dielectric loss tangent was increased to 0.11. A discussion of the possible mechanisms of MXene intercalation influence on the dielectric properties of PVDF/Ti3C2Tx MXene nanocomposites is presented.
Improved Visible-Light Photocatalytic H2 Evolution of G-C3N4 Nanosheets by Constructing Heterojunctions with Nano-Sized Poly(3-Thiophenecarboxylic Acid) and Coordinating Fe(III)
Authors: Li Yong , Zhang Bingmiao , Pang Xulong , Li Zhijun , Zhang Yi , Hao Ming , Zhu Yan , Qin Chuanli , Jing Liqiang
Published: April 2023

It is highly desirable to enhance the photogenerated charge separation of g-C3N4 by constructing efficient heterojunctions, especially with an additional organic constitution for solar–hydrogen conversion. Herein, g-C3N4 nanosheets have been modified controllably with nano-sized poly(3-thiophenecarboxylic acid) (PTA) through in situ photopolymerization and then coordinated with Fe(III) via the -COOH groups of modified PTA, forming an interface of tightly contacted nanoheterojunctions between the Fe(III)-coordinated PTA and g-C3N4. The resulting ratio-optimized nanoheterojunction displays a ~4.6-fold enhancement of the visible-light photocatalytic H2 evolution activity compared to bare g-C3N4. Based on the surface photovoltage spectra, measurements of the amount of •OH produced, photoluminescence (PL) spectra, photoelectrochemical curves, and single-wavelength photocurrent action spectra, it was confirmed that the improved photoactivity of g-C3N4 is attributed to the significantly promoted charge separation by the transfer of high-energy electrons from the lowest unoccupied molecular orbital (LUMO) of g-C3N4 to the modified PTA via the formed tight interface, dependent on the hydrogen bond interaction between the -COOH of PTA and the -NH2 of g-C3N4, and the continuous transfer to the coordinated Fe(III) with -OH favorable for connection with Pt as the cocatalyst. This study demonstrates a feasible strategy for solar-light-driven energy production over the large family of g-C3N4 heterojunction photocatalysts with exceptional visible-light activities.
In Situ Growth of Graphene on Polyimide for High-Responsivity Flexible PbS–Graphene Photodetectors
Authors: Hu Liangchen , Deng Jun , Xie Yiyang , Qian Fengsong , Dong Yibo , Xu Chen
Published: April 2023

Graphene is an ideal material for flexible optoelectronic devices due to its excellent electrical and optical properties. However, the extremely high growth temperature of graphene has greatly limited the direct fabrication of graphene-based devices on flexible substrates. Here, we have realized in situ growth of graphene on a flexible polyimide substrate. Based on the multi-temperature-zone chemical vapor deposition cooperated with bonding a Cu-foil catalyst onto the substrate, the growth temperature of graphene was controlled at only 300 °C, enabling the structural stability of polyimide during growth. Thus, large-area high-quality monolayer graphene film was successfully in situ grown on polyimide. Furthermore, a PbS–graphene flexible photodetector was fabricated using the graphene. The responsivity of the device reached 105 A/W with 792 nm laser illumination. The in-situ growth ensures good contact between graphene and substrate; therefore, the device performance can remain stable after multiple bending. Our results provide a highly reliable and mass-producible path for graphene-based flexible devices.
Green Synthesis: The Antibacterial and Photocatalytic Potential of Silver Nanoparticles Using Extract of Teucrium stocksianum
Authors: Rehman Iqra , Gondal Humaira Yasmeen , Zamir Roshan , Al-Hussain Sami A. , Batool Fozia , Irfan Ali , Noreen Sobia , Roheen Taleeha , Nisar Muhammad , Zaki Magdi E. A.
Published: April 2023

Green synthesis is one of the promising pathways for biologically active nanoscale materials. Herein, an eco-friendly synthesis of silver nanoparticles (SNPs) was carried out using an extract of Teucrium stocksianum. The biological reduction and size of NPS were optimized by controlling the physicochemical parameters such as concentration, temperature, and pH. A comparison of fresh and air-dried plant extracts was also undertaken to establish a reproducible methodology. The biosynthesized SNPs were characterized by UV–Vis spectroscopy, FT-IR, SEM, DLS, and XRD analyses. The prepared SNPs exhibited significant biological potential against multi-drug-resistant pathogenic strains. The results revealed that the biosynthesized SNPs exhibit high antimicrobial activity at low concentrations compared to the parent plant extract. Minimum inhibition concentration (MIC) values were found between 5.3 µg/mL to 9.7 µg/mL for the biosynthesized SNPs, whereas the aqueous extract of the plant showed many high values of MIC, i.e., between 69 and 98 µg/ML. Furthermore, the synthesized SNPs were found efficient in the photolytic degradation of methylene blue under sunlight.
Exploring the Impact of Nitrogen Doping on the Optical Properties of Carbon Dots Synthesized from Citric Acid
Authors: Olla Chiara , Cappai Antonio , Porcu Stefania , Stagi Luigi , Fantauzzi Marzia , Casula Maria Francesca , Mocci Francesca , Corpino Riccardo , Chiriu Daniele , Ricci Pier Carlo , Carbonaro Carlo Maria
Published: April 2023

The differences between bare carbon dots (CDs) and nitrogen-doped CDs synthesized from citric acid as a precursor are investigated, aiming at understanding the mechanisms of emission and the role of the doping atoms in shaping the optical properties. Despite their appealing emissive features, the origin of the peculiar excitation-dependent luminescence in doped CDs is still debated and intensively being examined. This study focuses on the identification of intrinsic and extrinsic emissive centers by using a multi-technique experimental approach and computational chemistry simulations. As compared to bare CDs, nitrogen doping causes the decrease in the relative content of O-containing functional groups and the formation of both N-related molecular and surface centers that enhance the quantum yield of the material. The optical analysis suggests that the main emission in undoped nanoparticles comes from low-efficient blue centers bonded to the carbogenic core, eventually with surface-attached carbonyl groups, the contribution in the green range being possibly related to larger aromatic domains. On the other hand, the emission features of N-doped CDs are mainly due to the presence of N-related molecules, with the computed absorption transitions calling for imidic rings fused to the carbogenic core as the potential structures for the emission in the green range.
Prevalence and Predictors of Food Insecurity among Students of a Spanish University during the COVID-19 Pandemic: FINESCOP Project at the UPV/EHU
Authors: González-Pérez Raquel , García-Iruretagoyena Laura , Martinez-Perez Naiara , Telleria-Aramburu Nerea , Telletxea Saioa , Padoan Sonia , Torheim Liv Elin , Arroyo-Izaga Marta
Published: April 2023

Research related to food insecurity (FI) among European university student populations is currently limited, especially the studies carried out during the COVID-19 pandemic. The present study aimed to assess the prevalence and identify possible predictors of FI among students from a Spanish public university, the University of the Basque Country UPV/EHU, during the COVID-19 pandemic. A cross-sectional observational study design was used, in which a total of 422 students completed an online survey. Results were weighted according to age and field of education. Binary logistic regressions adjusted by sex, age, and campus were applied to identify FI predictors. FI in 19.6, 2.6, and 0.7% of the population was mild, moderate, and severe, respectively. The three main predictors of FI were a decrease in the main source of income (OR, 2.80; 95% IC, 2.57–3.06), not receiving scholarships during the pandemic (OR, 2.32; 95% IC, 2.18–2.47), and living arrangements before the pandemic (not living with parents/relatives) (OR, 2.03, 95% IC, 1.89–2.18). This study found a high prevalence of FI among the students surveyed, and the strongest predictors of this FI were related to socioeconomic status. A robust and comprehensive policy response is recommended to mitigate FI in this population.
Hepatic G Protein-Coupled Receptor 180 Deficiency Ameliorates High Fat Diet-Induced Lipid Accumulation via the Gi-PKA-SREBP Pathway
Authors: Zhang Yunhua , Zhu Ziming , Sun Lijun , Yin Wenzhen , Liang Yuan , Chen Hong , Bi Yanghui , Zhai Wenbo , Yin Yue , Zhang Weizhen
Published: April 2023

Single-nucleotide polymorphisms in G protein-coupled receptor 180 (GPR180) are associated with hypertriglyceridemia. The aim of this study was to determine whether hepatic GPR180 impacts lipid metabolism. Hepatic GPR180 was knocked down using two approaches: Gpr180-specific short hairpin (sh)RNA carried by adeno-associated virus 9 (AAV9) and alb-Gpr180−/− transgene established by crossbreeding albumin-Cre mice with Gpr180flox/flox animals, in which Gpr180 was specifically knocked down in hepatocytes. Adiposity, hepatic lipid contents, and proteins related to lipid metabolism were analyzed. The effects of GPR180 on triglyceride and cholesterol synthesis were further verified by knocking down or overexpressing Gpr180 in Hepa1-6 cells. Gpr180 mRNA was upregulated in the liver of HFD-induced obese mice. Deficiency of Gpr180 decreased triglyceride and cholesterol contents in the liver and plasma, ameliorated hepatic lipid deposition in HFD-induced obese mice, increased energy metabolism, and reduced adiposity. These alterations were associated with downregulation of transcription factors SREBP1 and SREBP2, and their target acetyl-CoA carboxylase. In Hepa1-6 cells, Gpr180 knockdown decreased intracellular triglyceride and cholesterol contents, whereas its overexpression increased their levels. Overexpression of Gpr180 significantly reduced the PKA-mediated phosphorylation of substrates and consequent CREB activity. Hence, GPR180 might represent a novel drug target for intervention of adiposity and liver steatosis.
The Effect of 4-Methylcatechol on Platelets in Familial Hypercholesterolemic Patients Treated with Lipid Apheresis and/or Proprotein Convertase Subtilisin Kexin 9 Monoclonal Antibodies
Authors: Konečný Lukáš , Hrubša Marcel , Karlíčková Jana , Carazo Alejandro , Javorská Lenka , Matoušová Kateřina , Krčmová Lenka Kujovská , Šmahelová Alena , Blaha Vladimír , Bláha Milan , Mladěnka Přemysl
Published: April 2023

Elevated low-density lipoprotein (LDL) cholesterol levels lead to atherosclerosis and platelet hyperaggregability, both of which are known culprits of arterial thrombosis. Normalization of LDL cholesterol in familial hypercholesterolemia (FH) is not an easy task and frequently requires specific treatment, such as regularly performed lipid apheresis and/or novel drugs such as proprotein convertase subtilisin kexin 9 monoclonal antibodies (PCSK9Ab). Moreover, a high resistance rate to the first-line antiplatelet drug acetylsalicylic acid (ASA) stimulated research of novel antiplatelet drugs. 4-methylcatechol (4-MC), a known metabolite of several dietary flavonoids, may be a suitable candidate. The aim of this study was to analyse the antiplatelet effect of 4-MC in FH patients and to compare its impact on two FH treatment modalities via whole-blood impedance aggregometry. When compared to age-matched, generally healthy controls, the antiplatelet effect of 4-MC against collagen-induced aggregation was higher in FH patients. Apheresis itself improved the effect of 4-MC on platelet aggregation and blood from patients treated with this procedure and pretreated with 4-MC had lower platelet aggregability when compared to those solely treated with PCKS9Ab. Although this study had some inherent limitations, e.g., a low number of patients and possible impact of administered drugs, it confirmed the suitability of 4-MC as a promising antiplatelet agent and also demonstrated the effect of 4-MC in patients with a genetic metabolic disease for the first time.
Taurine: A Source and Application for the Relief of Visual Fatigue
Authors: Duan Hao , Song Wei , Guo Jinhong , Yan Wenjie
Published: April 2023

According to reports, supplementation with appropriate doses of taurine may help to reduce visual fatigue. Presently, some progress has been made in research related to taurine in eye health, but the lack of systematic summaries has led to the neglect of its application in the relief of visual fatigue. This paper, therefore, provides a systematic review of the sources of taurine, including the endogenous metabolic and exogenous dietary pathways, as well as a detailed review of the distribution and production of exogenous taurine. The physiological mechanisms underlying the production of visual fatigue are summarized and the research progress of taurine in relieving visual fatigue is reviewed, including the safety of consumption and the mechanism of action in relieving visual fatigue, in order to provide some reference basis and inspiration for the development and application of taurine in functional foods for relieving visual fatigue.
Revisiting PINI Scoring in Light of Recent Biological Advances
Authors: Ingenbleek Yves
Published: April 2023

The prognostic inflammatory and nutritional index (PINI) is a simple scoring formula allowing the follow-up of dietary protein restriction and infectious complications affecting critically ill patients hospitalized in medical and surgical wards. The World Health organization (WHO) has recently recommended using the binary CRP (C-reactive protein) and AGP (α1-acid glycoprotein) numerators of the PINI formula in underprivileged inhabitants of developing countries to evaluate their (sub)clinical infectious states making their chronic malnutrition worse. These studies, mainly located in Africa and Asia, demonstrate that children and women enduring the combined effects of infectious burden and (micro)nutrient deprivation (principally retinol and iron) usually manifest persistent refractoriness and slackened recovery throughout dietary rehabilitation. The additive measurement of ALB (albumin) and TTR (transthyretin) composing the denominator of the PINI formula is shown to be helpful in grading the downsizing of lean body mass (LBM), a cornerstone of bodybuilding. The confrontation of these four objective parameters thus allows the quantification of the respective importance of nutritional and inflammatory components of any disease process, taking into account that TTR is the sole plasma protein remaining highly correlated to the fluctuations of LBM. The below review highlights the prevailing roles played by protein nutritional states in the release of plasma retinol to target tissues and to the restoration of iron-deficient anemias.