bluuebunny/crossref_metadata_2025 huggingface dataset:
Meta-Analysis of the Effect of Saline-Alkali Land Improvement and Utilization on Soil Organic Carbon
Authors: Yang Shuai , Hao Xinghai , Xu Yiming , Yang Juejie , Su Derong
Published: November 2022

There is a large amount of saline-alkali land in China. Through the improvement and utilization of saline-alkali land to improve the carbon content in soil, it can not only become a reserve resource of cultivated land or grazing grassland, but also become an important land “carbon sink”. In this study, we performed a comprehensive meta-analysis to identify the impact of improvement and utilization of saline-alkali soil on soil organic carbon (SOC) in China. Our results showed that the soil salt and alkali content in Heilongjiang Province and Jilin Province in China was the highest, with an SOC content between 3.05 and 17.8 g/kg and pH between 8.84 and 9.94. Among the five methods of reclamation, halophyte planting, fertilization, biochar and modifier application, only biochar and modifier application significantly increased the SOC content (p < 0.05). The content of SOC in saline-alkali soil was 2.9–6.3 g/kg before biochar application, and significantly increased to 6.2–13.05 g/kg after biochar application (p < 0.01). The SOC content was 3.05–8.12 g/kg before the application of the modifier, and significantly increased to 3.68–9 g/kg (p < 0.05) after the application of the modifier. After utilization and improvement of saline-alkali land, the total nitrogen, available phosphorus and available potassium also increased significantly (p < 0.05). This study provides a scientific basis for further understanding the improvement and utilization of saline-alkali land in China and its potential for increasing carbon sinks.
Challenges to Promoting Resilience in Supply Chains Observed during the COVID-19 Pandemic: An Exploratory Study of the Amazon Region Using the TOPSIS Technique
Authors: Tadaiesky Dhiordan Cunha , Neto Joaquim Lima das Neves , Melo André Cristiano Silva , Anholon Rosley , de Castro Coutinho Eliane , Martins Vitor William Batista
Published: November 2022

Background: The COVID-19 pandemic has moved the world in every way, directly impacting supply chains globally and bringing major challenges to management, decision-makers, and companies of all sizes and sectors. This intensifies when it comes to the Brazilian Amazon region, a place that historically already lives with several maintenance projects focused on supply chain management (SCM). Methods: Thus, this research aimed to understand the main challenges faced by professionals in the supply chain area in the Amazon region through the development of a survey with professionals in the area. This study conducted a structured questionnaire containing 10 challenges related to SCM during the pandemic period to generate a ranking of these challenges using data analysis using means and comparative ordering using the TOPSIS Multicriteria Technique. Results: It was observed that the most relevant challenges for companies in this region were, respectively, distribution, economic problems, and interruptions in supply and demand. These obstacles promote debates with the literature and foster the expansion of knowledge about the insertion of resilience elements in supply chains in the Amazon. Conclusions: From a theoretical point of view and because it is exploratory research, the results serve as a basis for researchers in the area who aim to understand and expand the debates on this topic through future research. From a practical point of view, the results can help supply chain managers in the Amazon region who work directly in its maintenance and aim to maintain its resilience, since they already have the main challenges for the proper functioning of supply chains identified and ranked. Because it is an exploratory study, the results achieved can contribute significantly to the expansion of debates in the area and in a practical way with managers involved in activities that compose supply chains.
The Combined Effects of Sliding Velocity and Martensite Volume Fraction on Tribological Behavior of a Dual-Phase Steel
Authors: Zhang Yunbo , Jourani Abdeljalil
Published: November 2022

The focus of this study was the combined effects of sliding velocity (SV) and martensite volume fraction (MVF) on the tribological behavior of dual-phase (DP) steel. Dry frictional tests were realized on a ball-on-disk tribometer by unidirectional sliding at 0.1 m/s, 0.6 m/s, and 1 m/s. Considering the increase in SV, both the friction coefficient (COF) and wear rate decrease due to the increase in oxidative wear. At 0.1 m/s, the major wear mechanism is abrasive wear, accompanied by partial material flaking and less oxidation wear; at 0.6 m/s, the wear mechanism is in the transition between abrasive wear and oxidation wear; at 1 m/s, oxidation wear becomes the dominant wear mechanism. For the same SV, specimens with lower MVF exhibited lower wear compared to specimens with higher MVF; this phenomenon is especially evident at low SV. As the SV increases, the effect of MVF on the wear decreases, and the velocity becomes the dominant factor.
On the Concurrent Bipartite Entanglement of a Spin-1 Heisenberg Diamond Cluster Developed for Tetranuclear Nickel Complexes
Authors: Ghannadan Azadeh , Karl’ová Katarína , Strečka Jozef
Published: November 2022

The bipartite entanglement of a quantum spin-1 Heisenberg diamond cluster in the presence of the external magnetic field is quantified through the negativity, which is calculated for spin pairs from a diagonal and a side of the diamond spin cluster taking into consideration two different coupling constants. The magnetic field may cause a few crossings of energy levels of the spin-1 Heisenberg diamond cluster, which is responsible at low enough temperatures for a stepwise dependence of the negativity on the magnetic field accompanied with a drop of the negativity at respective magnetic-field-driven transitions due to emergence of mixed states. It is shown that the bipartite entanglement between spin pairs on a diagonal and a side of the diamond spin cluster is concurrent although they may eventually become both nonzero albeit not fully saturated. It is predicted that the tetranuclear nickel complex [Ni4(μ-CO3)2(aetpy)8](ClO4)4 (aetpy = 2-aminoethyl-pyridine), which represents an experimental realization of the spin-1 Heisenberg diamond cluster with two different antiferromagnetic coupling constants, exhibits a substantial bipartite entanglement between two spin-1 Ni2+ magnetic ions from a shorter diagonal of the diamond spin cluster up to temperatures approximately about 50 K and up to magnetic fields about 70 T.
Reliability Assessment of Heavily Censored Data Based on E-Bayesian Estimation
Authors: Liu Tianyu , Zhang Lulu , Jin Guang , Pan Zhengqiang
Published: November 2022

The classic E-Bayesian estimation methods can only derive point estimation of the reliability parameters. In this paper, an improved E-Bayesian estimation method is proposed to evaluate product reliability under heavily censored data, which can achieve both point and confidence interval estimation for the reliability parameters. Firstly, by analyzing the concavity & convexity and function characteristics of the Weibull distribution, the value of product failure probability is limited to a certain range. Secondly, an improved weighted least squares method is utilized to construct the confidence interval estimation model of reliability parameters. Simulation results show that the proposed approach can significantly improve the calculation speed and estimation accuracy with just very few robustness reductions. Finally, a real-world case study of the sun gear transmission mechanism is used to validate the effectiveness of the presented method.
A Finite Volume Method to Solve the Ill-Posed Elliptic Problems
Authors: Sheng Ying , Zhang Tie
Published: November 2022

In this paper, we propose a finite volume element method of primal-dual type to solve the ill-posed elliptic problem, that is, the elliptic problem with lacking or overlapping boundary value condition. We first establish the primal-dual finite volume element scheme by introducing the Lagrange multiplier λ and prove the well-posedness of the discrete scheme. Then, the error estimations of the finite volume solution are derived under some proper norms including the H1-norm. Numerical experiments are provided to verify the effectiveness of the proposed finite volume element method at last.
Topologies of Bihyperbolic Numbers
Authors: Savić Ana , Bilgin Merve , Ersoy Soley , Paunović Marija
Published: November 2022

In this paper, we establish a correlation between the bihyperbolic numbers set and the semi-Euclidean space. There are three different norms on the semi-Euclidean space that allow us to define three different hypersurfaces on semi-Euclidean space. Hence, we construct some topological structures on these hypersurfaces called norm e, s, and t topologies. On the other hand, we introduce hyperbolic e, s, and t topologies on the bihyperbolic numbers set. Moreover, by using the idempotent and spectral representations of the bihyperbolic numbers, we introduce new topologies on the bihyperbolic numbers set.
A Global Neighborhood with Hill-Climbing Algorithm for Fuzzy Flexible Job Shop Scheduling Problem
Authors: Seck-Tuoh-Mora Juan Carlos , Escamilla-Serna Nayeli Jazmín , Montiel-Arrieta Leonardo Javier , Barragan-Vite Irving , Medina-Marin Joselito
Published: November 2022

The Flexible Job Shop Scheduling Problem (FJSSP) continues to be studied extensively to test new metaheuristics and because of its closeness to current production systems. A variant of the FJSSP uses fuzzy processing times instead of fixed times. This paper proposes a new algorithm for FJSSP with fuzzy processing times called the global neighborhood with hill-climbing algorithm (GN-HC). This algorithm performs solution exploration using simple operators concurrently for global search neighborhood handling. For local search, random restart hill-climbing is applied at each solution to find the best machine for each operation. For the selection of operations in hill climbing, a record of the operations defining the fuzzy makespan is employed to use them as a critical path. Finally, an estimation of the crisp makespan with the longest processing times in hill climbing is made to improve the speed of the GN-HC. The GN-HC is compared with other recently proposed methods recognized for their excellent performance, using 6 FJSSP instances with fuzzy times. The obtained results show satisfactory competitiveness for GN-HC compared to state-of-the-art algorithms. The GN-HC implementation was performed in Matlab and can be found on GitHub (check Data Availability Statement at the end of the paper).
Dynamic Multicriteria Game with Pollution Externalities
Authors: Rettieva Anna
Published: November 2022

The multicriteria approach deals with real-life applications of game theory. However, the existing game-theoretic statements with the joint analysis of resource extraction and pollution dynamics have not considered the multiple objectives of the players. To address this issue, a dynamic multicriteria game is proposed: many players exploit a common resource and seek to optimize different criteria under pollution externalities. Two interconnected state variables (resource stock and pollution level) are introduced and studied. The pollution level depends on exploitation strategies, and the players have an environmental objective to reduce the accumulated pollution. The noncooperative and cooperative behavioral strategies of the players are analyzed. A linear dynamic multicriteria bioresource management problem with pollution externalities is investigated to illustrate the solution concepts proposed. The differences between the noncooperative and cooperative cases, as well as between the models with and without environmentally concerned players, are treated analytically and numerically. As shown by the results, the cooperative behavior reduces pollution in both statements, bringing to sparing bioresource exploitation.
Fixed Point Theorems on Almost (φ,θ)-Contractions in Jleli-Samet Generalized Metric Spaces
Authors: Dumitrescu Doru , Pitea Ariana
Published: November 2022

In this paper, we present extensions of some classic results regarding the existence and uniqueness of fixed points of operators fulfilling generalized contractive conditions defined by sums involving some functions with suitable properties in the setting of Jleli–Samet generalized metric spaces. As a consequence, some known results in the literature are obtained. Examples are provided to prove the usability of our developments.
One-Step Suicide Substrate Inactivation Kinetics of a Ping-Pong Reaction with One Substrate Undergoing Disproportionation: A Theoretical Approach with Approximate Solutions
Authors: Gutiérrez-Fernández Ismael , Bendou Ouardia , Bueno-Ramos Nara , Marcos-Barbero Emilio L. , Morcuende Rosa , Arellano Juan B.
Published: November 2022

Understanding the kinetic mechanism of enzyme inactivation by suicide substrate is of relevance for the optimal design of new drugs with pharmacological and therapeutic applications. Suicide substrate inactivation usually occurs via a two-step mechanism, although there are enzymes such as peroxidase and catalase in which the suicide inactivation by H2O2 happens in a single step. The approximate solution of the ordinary differential equation (ODE) system of the one step suicide substrate inactivation kinetics for a uni–uni reaction following the irreversible Michaelis–Menten model was previously analytically solved when accumulation of the substrate–enzyme complex was negligible, however not for more complex models, such as a ping-pong reaction, in which the enzyme is present in two active states during the catalytic turnover. To solve this issue, a theoretical approach was followed, in which the standard quasi-steady state and reactant stationary approximations were invoked. These approximations allowed for solving the ODE system of a ping-pong reaction with one substrate undergoing disproportionation when suicide inactivation was also present. Although the approximate analytical solutions were rather unwieldy, they were still valuable in qualitative analyses to explore the time course of the reaction products and identify the enzyme active state that irreversibly reacted with the suicide substrate during the reaction.
Influence of Oxidation and Dialysis of Phlorotannins on Bioactivity and Composition of Ultrasound-Assisted Extracts from Ascophyllum nodosum
Authors: Gisbert Mauro , Sineiro Jorge , Moreira Ramón
Published: November 2022

The isolation and chemical characterization of phlorotannins has gained special attention in recent years due to their specific health-promoting benefits. Flow-cell ultrasound-assisted extraction (90 W/cm2 of sonication power, 2 min of retention time and 20 g solvent/g algae of liquid–solid ratio) was carried out by using double-distilled water (WE) and acetone:water mixture (AWE) as extraction solvents. The AWE showed a higher total polyphenols content (TPC), carbohydrates (CHOs) and antioxidant activities than WE. However, when the WE was purified by using Amberlite XAD16 column, the purified WE (PWE) showed similar a TPC, decreased CHOs and increased antioxidant activity compared to WE. The oxidation of the PWE extract was evaluated under natural, forced and severe oxidation condition for 120 h. Only severe oxidation conditions were able to significantly reduce TPC and antioxidant activities. PWE was dialyzed (20, 10, 3.5 and 2 kDa). The main bioactive fraction of phlorotannins was obtained from 10 to 20 kDa. CHOs were distributed in fractions below 20 kDa. MALDI-TOF analysis was performed for PWE, PD20 and PD2 extracts to analyze the degree of polymerization of phlorotannins, which ranged from 4 to 17 phloroglucinol units/molecule. Fragmentation patterns allowed the proximate identification of several phlorotannins in Ascophyllum nodosum extracts.
Relationship between Outerbridge Scale and Chondropathy Femorotibial Joint in Relation to Gender and Age—The Use of 1.5T and 3.0T MRI Scanners
Authors: Sieroń Dominik , Jabłońska Izabella , Niemiec Paweł , Lukoszek Dawid , Szyluk Karol , Platzek Ivan , Meusburger Hugo , Delimpasis Georgios , Christe Andreas
Published: November 2022

Background and Objective: Magnetic resonance imaging (MRI) enables the effective evaluation of chondromalacia of the knee joint. Cartilage disease is affected by many factors, including gender, age, and body mass index (BMI). The aim of this study was to check the relationship between the severity of chondromalacia of the femoro-tibial joint and age, gender, and BMI assessed with 1.5T and 3.0T MRI scanners. Materials and Methods: The cross-observational study included 324 patients—159 (49%) females and 165 (51%) males aged 8–87 (45.1 ± 20.9). The BMI of study group was between 14.3 and 47.3 (27.7 ± 5.02). 1.5T and 3.0T MRI scanners were used in the study. The articular cartilage of the knee joint was assessed using the Outerbridge scale. Results: The age of the patients showed a significant correlation with Outerbrige for each compartment of the femorotibial joint (Spearman’s rank correlation rho: 0.69–0.74, p < 0.0001). A higher correlation between BMI and Outerbridge was noted in the femur medial (rho = 0.45, p < 0.001) and the tibia medial (rho = 0.43, p < 0.001) than in the femur lateral (rho = 0.29, p < 0.001) and the tibia lateral compartment (rho = 0.34, p < 0.001). Conclusions: The severity of chondromalacia significantly depends on age and BMI level, regardless of gender.
Affinity of Compounds for Phosphatydylcholine-Based Immobilized Artificial Membrane—A Measure of Their Bioconcentration in Aquatic Organisms
Authors: Sobańska Anna W.
Published: November 2022

The BCF (bioconcentration factor) of solutes in aquatic organisms is an important parameter because many undesired chemicals enter the ecosystem and affect the wildlife. Chromatographic retention factor log kwIAM obtained from immobilized artificial membrane (IAM) HPLC chromatography with buffered, aqueous mobile phases and calculated molecular descriptors obtained for a group of 120 structurally unrelated compounds were used to generate useful models of log BCF. It was established that log kwIAM obtained in the conditions described in this study is not sufficient as a sole predictor of bioconcentration. Simple, potentially useful models based on log kwIAM and a selection of readily available, calculated descriptors and accounting for over 88% of total variability were generated using multiple linear regression (MLR), partial least squares (PLS) regression and artificial neural networks (ANN). The models proposed in the study were tested on an external group of 120 compounds and on a group of 40 compounds with known experimental log BCF values. It was established that a relatively simple MLR model containing four independent variables leads to satisfying BCF predictions and is more intuitive than PLS or ANN models.
Light Response and Switching Behavior of Graphene Oxide Membranes Modified with Azobenzene Compounds
Authors: Sadilov Ilia , Petukhov Dmitrii , Brotsman Victor , Chumakova Alexandra , Eliseev Artem , Eliseev Andrei
Published: November 2022

Here, we report on the fabrication of light-switchable and light-responsive membranes based on graphene oxide (GO) modified with azobenzene compounds. Azobenzene and para-aminoazobenzene were grafted onto graphene oxide layers by covalent attachment/condensation reaction prior to the membranes’ assembly. The modification of GO was proven by the UV-vis, IR, Raman and photoelectron spectroscopy. The membrane’s light-responsive properties were investigated in relation to the permeation of permanent gases and water vapors under UV and IR irradiation. Light irradiation does not influence the permeance of permanent gases, while it strongly affected that of water vapors. Both switching and irradiation-induced water permeance variation is described, and they were attributed to over 20% of the initial permeance. According to in situ diffraction studies, the effect is ascribed to the change to the interlayer distance between the graphene oxide nanoflakes, which increases under UV irradiation to ~1.5 nm while it decreases under IR irradiation to ~0.9 nm at 100% RH. The last part occurs due to the isomerization of grafted azobenzene under UV irradiation, pushing apart the GO layers, as confirmed by semi-empirical modelling.
The Use of Polymer Inclusion Membranes for the Removal of Metal Ions from Aqueous Solutions—The Latest Achievements and Potential Industrial Applications: A Review
Authors: Kaczorowska Małgorzata A.
Published: November 2022

The growing demand for environmentally friendly and economical methods of removing toxic metal ions from polluted waters and for the recovery of valuable noble metal ions from various types of waste, which are often treated as their secondary source, has resulted in increased interest in techniques based on the utilization of polymer inclusion membranes (PIMs). PIMs are characterized by many advantages (e.g., the possibility of simultaneous extraction and back extraction, excellent stability and high reusability), and can be adapted to the properties of the removed target analyte by appropriate selection of carriers, polymers and plasticizers used for their formulation. However, the selectivity and efficiency of the membrane process depends on many factors (e.g., membrane composition, nature of removed metal ions, composition of aqueous feed solution, etc.), and new membranes are systematically designed to improve these parameters. Numerous studies aimed at improving PIM technology may contribute to the wider use of these methods in the future on an industrial scale, e.g., in wastewater treatment. This review describes the latest achievements related to the removal of various metal ions by PIMs over the past 3 years, with particular emphasis on solutions with potential industrial application.
Current State-of-the-Art in Membrane Formation from Ultra-High Molecular Weight Polyethylene
Authors: Basko Andrey , Pochivalov Konstantin
Published: November 2022

One of the materials that attracts attention as a potential material for membrane formation is ultrahigh molecular weight polyethylene (UHMWPE). One potential material for membrane formation is ultrahigh molecular weight polyethylene (UHMWPE). The present review summarizes the results of studies carried out over the last 30 years in the field of preparation, modification and structure and property control of membranes made from ultrahigh molecular weight polyethylene. The review also presents a classification of the methods of membrane formation from this polymer and analyzes the conventional (based on the analysis of incomplete phase diagrams) and alternative (based on the analysis of phase diagrams supplemented by a boundary line reflecting the polymer swelling degree dependence on temperature) physicochemical concepts of the thermally induced phase separation (TIPS) method used to prepare UHMWPE membranes. It also considers the main ways to control the structure and properties of UHMWPE membranes obtained by TIPS and the original variations of this method. This review discusses the current challenges in UHMWPE membrane formation, such as the preparation of a homogeneous solution and membrane shrinkage. Finally, the article speculates about the modification and application of UHMWPE membranes and further development prospects. Thus, this paper summarizes the achievements in all aspects of UHMWPE membrane studies.
Effect of Packing Nonuniformity at the Fiber Bundle–Case Interface on Performance of Hollow Fiber Membrane Gas Separation Modules
Authors: Sun Lili , Panagakos Grigorios , Lipscomb Glenn
Published: November 2022

High-fidelity simulations of momentum and mass transfer within a hollow fiber gas separation membrane module are here reported. The simulations capture the potential detrimental effects of poor fiber packing at the bundle–case interface on fluid distribution and performance. Results are presented for both circular and planar fiber bundles. The length over which bundle–case gaps affects flow is determined. The length increases dramatically with increasing fiber packing fraction. As the packing fraction approaches 0.6, the impact extends over the entire bundle diameter for small modules (<1000 fibers). The results clearly demonstrate the detrimental effect of poor packing along the case and can be used to develop module manufacturing guidelines. To reduce computational costs, an equivalent planar bundle module approximation is developed. The approximate simulations agree well with results from full 3-D simulations and can reduce computational costs without sacrificing fidelity.
Phase Formation, Microstructure, and Mechanical Properties of Ni-Cu Bimetallic Materials Produced by Electron Beam Additive Manufacturing
Authors: Osipovich Kseniya , Gurianov Denis , Vorontsov Andrey , Knyazhev Evgeny , Panfilov Alexander , Chumaevskii Andrey , Savchenko Nikolai , Nikonov Sergey , Rubtsov Valery , Kolubaev Evgeny
Published: November 2022

The paper presents the results of applying wire-feed electron beam additive manufacturing technology to produce bimetallic samples of CuCr1 copper alloy and Udimet 500 nickel-based superalloy. Different printing strategies were used to obtain samples with a defect-free structure and high mechanical properties in the transition zone, not inferior to the strength of copper alloy. Two types of samples were fabricated with a sharp and smooth CuCr1/Udimet 500 interface. The printing strategies of type I and II samples differed in the combination and arrangement of nickel and copper alloy layers. Structural studies in the transition zone revealed mechanical mixtures of initial copper and nickel alloy components and solid solutions based on nickel, copper, and chromium. Despite the presence of defects and structural heterogeneities in the experimental samples, the mechanical properties of the main components are at a high level, corresponding to the typical properties of copper and nickel alloys. The strength of the transition zone in type II samples is between the strength of Udimet 500 and CuCr1.
Microstructural Evolution of Wrought-Nickel-Based Superalloy GH4169
Authors: Zhou Wei , Chen Xiaohua , Wang Yanlin , Chen Kaixuan , Zhu Yuzhi , Qin Junwei , Wang Zidong , Zuo Lingli
Published: November 2022

To investigate the microstructural evolution of wrought-nickel-based superalloy GH4169 from the original ingot to the finished product of manufacturing processes, different kinds of etchants and etching methods were used to show the fine precipitates and their morphologies. The obtained microstructures can vary in size, type, distribution, location, formation, and interactions of multiple phases, which were observed and analyzed by optical microscopy (OM), scanning electron microscopy (SEM), and an energy dispersive spectrometer (EDS). The dendrite segregation behavior of as-cast superalloy GH4169 was investigated. In addition, the microstructural evolution mechanism of second-phase particles during dynamic recrystallization was analyzed. This work sheds light on the evolution of the second-phase structure of nickel-based superalloys during the preparation process, providing guidance for process development and visual interpretation of the relationships between microstructure and properties.
Researches on the Macro- and Micro-Structures and Properties of the Vertical Bending Continuous Casted AA6063 Thin Slabs and Their As-Rolled Sheets
Authors: Wu Zhuo-Huang , Mao Qi-Jia , Hua Fu-An , Jia Guang-Lin , Li Jian-Ping , Li Cheng-Gang , Yuan Guo , Wang Guo-Dong
Published: November 2022

A 6063 aluminum alloy thin slab with a cross-section of 260 × 40 mm2 was prepared by a vertical bending continuous casting (VC) process. The effects of homogenization, hot rolling and subsequent heat treatments on the microstructure and properties of the as-cast slabs and as-rolled sheets were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), field emission electron probe (EPMA), macro- and micro-structure observation and tensile tests. The results show that the as-cast structure of AA 6063 was dominated by fine and uniform equiaxed grains. After homogenization, all Mg2Si phases dissolved back, and the Fe-containing intermetallic phases changed from acicular β-Al5FeSi phase to spherical α-Al8Fe2Si phase. Homogenizing heat treatment before hot rolling can improve the mechanical properties of the alloy. However, in the case of direct rolling without homogenization, the alloy still has good mechanical properties; the strength and plasticity are comparable to that obtained through traditional direct chill (DC) casting, homogenizing and extruding processes, indicating that the VC process has the potential to realize continuous casting and rolling.
Investigation of Collision Toughness and Energy Distribution for Hot Press Forming Center Pillar Applied with Combination Techniques of Patchwork and Partial Softening Using Side Crash Simulation
Authors: Lee Min Sik , Jin Chul Kyu , Suh Junho , Lee Taekyung , Lim Ok Dong
Published: November 2022

Various techniques can be applied to center pillars to enhance collision characteristics during side crashes. For instance, patchwork (PW) can be welded to the center pillar to increase its stiffness, and partial softening (PS) can be applied to provide ductility. Side crash tests are conducted by the Insurance Institute for Highway Safety (IIHS) to evaluate collision resistance. However, it is difficult to evaluate collision toughness and energy distribution flow for each automobile component. In this study, a side crash simulation was performed with IIHS instruction. We investigated the effect of hot press forming (HPF) a center pillar with a combination of PW and PS techniques on collision toughness and energy distribution flow. As a result, the role of PW and PS techniques were verified during side crashes. PW improved the strain energy and intrusion displacement by 10% and 7.5%, respectively, and PS improved the plastic deformation energy and intrusion displacement by 10%. When PW and PS were applied to the HPF center pillar simultaneously, a synergistic effect was achieved.
Strain Hardening Exponent and Strain Rate Sensitivity Exponent of Cast AZ31B Magnesium Alloy
Authors: Zhu Yanchun , Wang Qinghua , Huang Zhiquan , Qin Ling , Li Ziliang , Ma Lifeng
Published: November 2022

The flow curves of as-cast AZ31B magnesium alloy during high temperature deformation were obtained with a thermal compression test, and the effects of deformation amount, grain size, strain rate, and deformation temperature on the flow stress, strain rate sensitivity index, and strain hardening index were analyzed. The results showed that deformation and grain size were negatively correlated with both the strain rate sensitivity index and strain hardening index. The increase in strain rate increased the strain hardening index but made the strain rate sensitivity index show an opposite trend. Increasing temperature reduced the strain rate sensitivity index and strain hardening index but, when the temperature exceeded 700 K, the strain rate sensitivity index was no longer affected by temperature. Since the strain rate sensitivity index m and strain hardening index n are important parameters for measuring the plastic deformation of metal materials, this study has great significance for guiding the selection of process parameters in the plastic processing of as-cast AZ31 magnesium alloy.
Nano Porous Zinc Synthesis on Soft Polyurethane Foam Using Conductive Ink and Electroplating Method
Authors: Salimi Mehdi , Mousavi Khoiee Seyed Mohammad , Keshavarz Alamdari Eskandar , Rezaei Milad , Karbasi Maryam
Published: November 2022

High specific surface is a significant characteristic in zinc coatings that can be highly applicable in batteries and catalysts. Conventional methods to create foams are not cost-efficient, nor could they make a high specific surface. Electroplating has been developed that can produce a very high specific surface foam. On the other hand, conductive ink can create an affordable conductive surface with a high specific surface, so the study on using conductive ink, which has a cost-efficient nature, was necessary to create a conductive surface. This work has investigated the effect of crucial parameters, such as graphite size, coating time and bath composition, on the current efficiency and SEM microstructure. As a result, a 3 µm graphite size was found to be appropriate. Coated zinc escalates linearly with current efficiency for up to 5 h, and then it decreases. Although the zinc concentration increases up to 0.12 mol/L in the electrolyte, making a slight increase in loading, the current efficiency was almost unchanged. However, if it increases more, the loading and current efficiency significantly rise so that the loading grows up to 16 times and the current density increases up to 86%. Additionally, the morphology changes from dendritic to compact plates, sphere and semi-sphere, subsequently.
SARS-CoV-2-Induced Amyloidgenesis: Not One, but Three Hypotheses for Cerebral COVID-19 Outcomes
Authors: Gonçalves Carlos-Alberto , Bobermin Larissa Daniele , Sesterheim Patricia , Netto Carlos Alexandre
Published: November 2022

The main neuropathological feature of Alzheimer’s disease (AD) is extracellular amyloid deposition in senile plaques, resulting from an imbalance between the production and clearance of amyloid beta peptides. Amyloid deposition is also found around cerebral blood vessels, termed cerebral amyloid angiopathy (CAA), in 90% of AD cases. Although the relationship between these two amyloid disorders is obvious, this does not make CAA a characteristic of AD, as 40% of the non-demented population presents this derangement. AD is predominantly sporadic; therefore, many factors contribute to its genesis. Herein, the starting point for discussion is the COVID-19 pandemic that we are experiencing and how SARS-CoV-2 may be able to, both directly and indirectly, contribute to CAA, with consequences for the outcome and extent of the disease. We highlight the role of astrocytes and endothelial cells in the process of amyloidgenesis, as well as the role of other amyloidgenic proteins, such as fibrinogen and serum amyloid A protein, in addition to the neuronal amyloid precursor protein. We discuss three independent hypotheses that complement each other to explain the cerebrovascular amyloidgenesis that may underlie long-term COVID-19 and new cases of dementia.
Fetal Exposure to Maternal Smoking and Neonatal Metabolite Profiles
Authors: Cajachagua-Torres Kim N. , Blaauwendraad Sophia M. , El Marroun Hanan , Demmelmair Hans , Koletzko Berthold , Gaillard Romy , Jaddoe Vincent W. V.
Published: November 2022

Fetal tobacco exposure has persistent effects on growth and metabolism. The underlying mechanisms of these relationships are yet unknown. We investigated the associations of fetal exposure to maternal smoking with neonatal metabolite profiles. In a population-based cohort study among 828 mother-infant pairs, we assessed maternal tobacco use by questionnaire. Metabolite concentrations of amino acids, non-esterified fatty acids, phospholipids and carnitines were determined by using LC-MS/MS in cord blood samples. Metabolite ratios reflecting metabolic pathways were computed. Compared to non-exposed neonates, those exposed to first trimester only tobacco smoking had lower neonatal mono-unsaturated acyl-alkyl-phosphatidylcholines (PC.ae) and alkyl-lysophosphatidylcholines (Lyso.PC.e) 18:0 concentrations. Neonates exposed to continued tobacco smoking during pregnancy had lower neonatal mono-unsaturated acyl-lysophosphatidylcholines (Lyso.PC.a), Lyso.PC.e.16:0 and Lyso.PC.e.18:1 concentration (False discovery rate (FDR) p-values < 0.05). Dose-response associations showed the strongest effect estimates in neonates whose mothers continued smoking ≥5 cigarettes per day (FDR p-values < 0.05). Furthermore, smoking during the first trimester only was associated with altered neonatal metabolite ratios involved in the Krebs cycle and oxidative stress, whereas continued smoking during pregnancy was associated with inflammatory, transsulfuration, and insulin resistance markers (p-value < 0.05). Thus, fetal tobacco exposure seems associated with neonatal metabolite profile adaptations. Whether these changes relate to later life metabolic health should be studied further.
Vitamin B12 (Cobalamin): Its Fate from Ingestion to Metabolism with Particular Emphasis on Diagnostic Approaches of Acquired Neonatal/Infantile Deficiency Detected by Newborn Screening
Authors: Kósa Magdolna , Galla Zsolt , Lénárt István , Baráth Ákos , Grecsó Nóra , Rácz Gábor , Bereczki Csaba , Monostori Péter
Published: November 2022

Acquired vitamin B12 (vB12) deficiency (vB12D) of newborns is relatively frequent as compared with the incidence of inherited diseases included in newborn screening (NBS) of different countries across the globe. Infants may present signs of vB12D before 6 months of age with anemia and/or neurologic symptoms when not diagnosed in asymptomatic state. The possibility of identifying vitamin deficient mothers after their pregnancy during the breastfeeding period could be an additional benefit of the newborn screening. Vitamin supplementation is widely available and easy to administer. However, in many laboratories, vB12D is not included in the national screening program. Optimized screening requires either second-tier testing or analysis of new urine and blood samples combined with multiple clinical and laboratory follow ups. Our scope was to review the physiologic fate of vB12 and the pathobiochemical consequences of vB12D in the human body. Particular emphasis was put on the latest approaches for diagnosis and treatment of vB12D in NBS.
Correlation between Serum Steroid Hormones and Gut Microbiota in Patients with Alcohol-Associated Liver Disease
Authors: Gao Bei , Zhu Yixin , Shen Weishou , Stärkel Peter , Schnabl Bernd
Published: November 2022

Alcohol-associated liver disease is a major public health concern globally. Alterations of steroid hormones and gut microbiota were both found in patients with alcohol-associated liver disease. However, their correlation has not been well characterized in these patients. In this study, we measured the level of 30 steroid hormones in serum and fecal samples collected from non-alcoholic controls, patients with alcohol use disorder, and patients with alcohol-associated hepatitis. The profile of serum and fecal steroid hormones was quite different in patients with alcohol-associated hepatitis from that in patients with alcohol use disorder and control subjects. Stronger alterations were observed in male patients than in females. Correlations were found not only between serum steroids and gut bacteria but also between serum steroids and gut fungi. These correlations need to be taken into consideration during the development of treatment strategies for alcohol-associated liver disease.
Reduced Steroid Metabolites Identify Infection-Prone Children in Two Independent Pre-Birth Cohorts
Authors: Prince Nicole , Kim Min , Kelly Rachel S. , Diray-Arce Joann , Bønnelykke Klaus , Chawes Bo L. , Huang Mengna , Levy Ofer , Litonjua Augusto A. , Stokholm Jakob , Wheelock Craig E. , Bisgaard Hans , Weiss Scott T. , Lasky-Su Jessica A.
Published: November 2022

Recurrent respiratory infections are a leading cause of morbidity and mortality in early life, but there is no broadly accepted means to identify infection-prone children during this highly vulnerable period. In this study, we investigated associations between steroid metabolites and incident respiratory infections in two pre-birth cohorts to identify novel metabolomic signatures of early infection proneness. Children from the Vitamin D Antenatal Asthma Reduction Trial and the Copenhagen Prospective Studies on Asthma in Childhood were included, and profiling was performed on plasma samples collected at ages 1 and 6 years. Both cohorts recorded incidence of lower respiratory infections, upper respiratory infections, ear infections, and colds. Poisson regression analysis assessed the associations between 18 steroid metabolites and the total number of respiratory infections that occurred in offspring during follow-up. We found that steroid metabolites across androgenic, corticosteroid, pregnenolone, and progestin classes were reduced in children that suffered more infections, and these patterns persisted at age 6 years, generally reflecting consistency in direction of effect and significance. Our analysis suggested steroid metabolite measurement may be useful in screening for infection proneness during this critical developmental period. Future studies should clinically evaluate their potential utility as a clinical screening tool.
Internal Resonance of the Coupling Electromechanical Systems Based on Josephson Junction Effects
Authors: Liu Canchang , Li Lijun , Zhang Yirui
Published: November 2022

The internal resonances of the coupling vibration among electro-dynamic modes of an NEMS are studied for the coupling resonators connected on a Josephson junction. The methodology adopted involves coupling a resonator connected on a Josephson junction. The mathematical model of the coupled system is then obtained by considering the regulatory nonlinear effect of the phase difference of that Josephson junction. The resulting dynamic differential equation is deduced by considering the nonlinear terms of the Josephson junction and the nanobeam. The multi-scale method is then used to obtain the 1:1:1 resonant amplitude–frequency response equation of the coupled electromechanical system. The influence of the phase difference of the Josephson junction, magnetic field, external excitation and other factors are analyzed based on the internal resonant amplitude of the coupled system. The simulation results illustrate that the changes in the values of the magnetic field, excitation amplitude and divided resistances can lead to a remarkable change in the values of the nanobeam frequency and amplitude. The internal resonance principle is used to generate a mutual conversion and amplification among electrical signals and mechanical signals. This research provides a theoretical framework and a numerical approach for improving the sensitivity of magnetic quality detection.
Widespread but Poorly Understood Bacteria: Candidate Phyla Radiation
Authors: Ji Yanhan , Zhang Ping , Zhou Sihan , Gao Ping , Wang Baozhan , Jiang Jiandong
Published: November 2022

Candidate Phyla Radiation (CPR) bacteria is a bacterial division composed mainly of candidate phyla bacteria with ultra-small cell sizes, streamlined genomes, and limited metabolic capacity, which are generally considered to survive in a parasitic or symbiotic manner. Despite their wide distribution and rich diversity, CPR bacteria have received little attention until recent years, and are therefore poorly understood. This review systematically summarizes the history of CPR research, the parasitic/symbiotic lifestyle, and the ecological distribution and unique metabolic features of CPR bacteria, hoping to provide guidance for future ecological and physiological research on CPR bacteria.
Direct Detection of Antibacterial-Producing Soil Isolates Utilizing a Novel High-Throughput Screening Assay
Authors: Laubscher Wikus Ernst , Rautenbach Marina
Published: November 2022

The ever-increasing global threat of common infections developing resistance to current therapeutics is rapidly accelerating the onset of a primitive post-antibiotic era in medicine. The prevention of further antimicrobial resistance development is unlikely due to the continued misuse of antibiotics, augmented by the lack of discovery of novel antibiotics. Screening large libraries of synthetic compounds have yet to offer effective replacements for current antibiotics. Due to historical successes, discovery from large and diverse natural sources and, more specifically, environmental bacteria, may still yield novel alternative antibiotics. However, the process of antibiotic discovery from natural sources is laborious and time-consuming as a result of outdated methodologies. Therefore, we have developed a simple and rapid preliminary screening assay to identify antibacterial-producing bacteria from natural sources. In brief, the assay utilizes the presence or absence of luminescence in bioluminescent reporter bacteria and test bacterium co-cultures in a 96-well plate format to determine the absence or presence of antibacterial compound production. Our assay, called the bioluminescent simultaneous antagonism (BSLA) assay, can accurately distinguish between known antibacterial-producing and non-producing test bacteria. The BSLA assay was validated by screening 264 unknown soil isolates which resulted in the identification of 10 antibacterial-producing isolates, effectively decreasing the pool of isolates for downstream analysis by 96%. By design, the assay is simple and requires only general laboratory equipment; however, we have shown that the assay can be scaled to automated high-throughput screening systems. Taken together, the BSLA assay allows for the rapid pre-screening of unknown bacterial isolates which, when coupled with innovative downstream dereplication and identification technologies, can effectively fast-track antimicrobial discovery.
Prevalence of mecA, mecC and Panton-Valentine-Leukocidin Genes in Clinical Isolates of Coagulase Positive Staphylococci from Dermatological Canine Patients
Authors: Platenik Marcela O. , Archer Linda , Kher Lopamudra , Santoro Domenico
Published: November 2022

Coagulase positive Staphylococci (CoPS) are the leading cause of canine cutaneous and otic infections. Virulence factors associated with Staphylococci include the expression of mec and panton-valentine leukocidin (pvl) genes. Methicillin-resistance (MR) is commonly associated with mecA gene expression, although a recently identified variant, mecC, has been reported. This study aims to evaluate the prevalence of mecA, mecC and pvl genes in 232 clinical isolates of CoPS collected from dogs with pyoderma. A multiplex PCR, and Kirby-Bauer disk diffusion susceptibility test for cefoxitin was performed for all isolates. PBP2a agglutination test was performed on 127 isolates. Standard MRSA isolates were used as positive controls. The mecA gene was identified in 149/232 isolates (64.2%): 116 S. pseudintermedius, 30 S. coagulans and three S. aureus. The pvl gene was present in only 1 isolate of S. pseudintermedius (0.4%), whereas no isolates carried the mecC gene. 34 isolates were resistant to cefoxitin (14.6%) and they were all mecA positive. The results of this study show an MR prevalence of 64.2% confirming concerns about antibiotic resistance in veterinary medicine. In conclusion, this is the first study analyzing the prevalence of mecC and pvl in comparison to mecA, in a large cohort of CoPS clinical isolates from dogs with pyoderma. A multimodal surveillance on the prevalence of mecC and pvl in veterinary medicine is essential to appropriate antimicrobial management.