bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic Matching and Spatial Optimization of Land Use and Resource-Environment Constraints in Typical Regions of the Yellow River Basin in China
Authors: Yu Ze , Su Desheng , Wang Shilei , Wei Chuanchen , Li Na , Qu Yanbo , Wang Meng
Published: July 2023

Accurately identifying the matching relationships between territorial space evolution and the resources and environment carrying capacity will directly guide the sustainable use of territorial space. Based on the evaluation of the territorial space dynamics of the lower Yellow River, this paper evaluates the suitability of territorial space development by focusing on ecological protection, agricultural development, and urban construction. Specifically, the resources and environment carrying capacity is estimated by identifying and mediating potential conflicts in the development of territorial space. The matching relationship between the evolution of territorial space and the resources and environment carrying capacity is identified using the matching degree model. The results demonstrated that: (1) Between 2000 and 2020, the agricultural space of the lower Yellow River was relatively stable, while the ecological space was generally shrinking, and the urban space continued to increase; (2) The characteristics of suitability for the agricultural development and urban construction of the lower Yellow River are characterized by landform and land-sea differentiation. The carrying scale of resources and the environment is based on agricultural space and is increasing yearly, followed by ecological space, which is gradually decreasing, and urban space, which first increased and then decreased; (3) Between 2000 and 2020, the matching index of the ecological and agricultural space evolution and the resource and environmental carrying capacity in the lower Yellow River exhibited a downward trend, while the regional difference increased. Furthermore, the matching index of urban space and the resources and environment carrying capacity indicated an upward trend, while the regional difference decreased.
Research on Social Service Effectiveness Evaluation for Urban Blue Spaces—A Case Study of the Huangpu River Core Section in Shanghai
Authors: Huang Jishu , Wang Yun
Published: July 2023

Urban blue spaces (UBSs) hold significant value in terms of public health, tourism economy, and residents’ well-being. The Huangpu River in Shanghai, renowned as a global urban blue space, currently faces challenges such as unequal service capacity across sections and varying levels of spatial vitality. This study incorporates the concept of “service effectiveness” into public space evaluation. Drawing inspiration from the 4E (economics, efficiency, equity, and effectiveness) principles of effectiveness evaluation, a social service effectiveness evaluation system is constructed to measure service efficiency and effect. Through the literature research, 6 primary indicators and 12 secondary indicators are set to investigate the utilization rate and realization effect of the UBS. The evaluation system utilizes field surveys, text analysis, and remote-sensing techniques to collect relevant data. Through standardized calculations, different aspects of the indicators are integrated into a single evaluation criterion. The “overall effectiveness index” and the “efficiency–effect balance index” is introduced to quantitatively analyze the overall effectiveness characteristics, including spatial characteristics and time-varying characteristics, as well as efficiency–effect balance and imbalances. The evaluation located three low-effectiveness sections and three imbalanced sections at the north and south ends of the core section of the Huangpu River. The influence factors of effectiveness are analyzed through correlation test and literature studies, mainly including the urban hinterland, service facilities, environmental quality, and management publicity factors. This study aims to provide research ideas and methods for waterfront area planning and city-refined management.
Collaborative Governance for Participatory Regeneration Practices in Old Residential Communities within the Chinese Context: Cases from Beijing
Authors: Zhang Zixuan , Pan Junchen , Qian Yun
Published: July 2023

The regeneration of old residential communities in China is one of the most important tasks in urban renewal. In recent years, distinctive models and pathways have emerged in the emerging practice of participatory community regeneration, all of which can be seen as applications of collaborative governance theory at the community level. Collaborative governance is considered an effective way to achieve multiple goals in urban regeneration, but there has been relatively little research on collaborative governance in small-scale regeneration projects. This paper summarizes three nuanced pathways in the collaborative governance model through case studies, which are led by different initiators, resulting in collaborative models, rights dynamics, and implementation pathways that are applicable to different scenarios, effectively resolving community conflicts and producing sustainable practical results. This study compares how the three models achieve their respective objectives in participatory regeneration projects by coordinating the different stakeholder participation processes. These three models complement and extend international experience and will provide a vivid Chinese example for other developing countries around the world.
Transcutaneous Spinal Cord Stimulation Facilitates Respiratory Functional Performance in Patients with Post-Acute COVID-19
Authors: Ovechkin Alexander , Moshonkina Tatiana , Shandybina Natalia , Lyakhovetskii Vsevolod , Gorodnichev Ruslan , Moiseev Sergey , Siu Ricardo , Gerasimenko Yury
Published: July 2023

Background: A growing number of studies have reported Coronavirus disease (COVID-19) related to both respiratory and central nervous system dysfunctions. This study evaluates the neuromodulatory effects of spinal cord transcutaneous stimulation (scTS) on the respiratory functional state in healthy controls and patients with post-COVID-19 respiratory deficits as a step toward the development of a rehabilitation strategy for these patients. Methods: In this before-after, interventional, case–controlled clinical study, ten individuals with post-acute COVID-19 respiratory deficits and eight healthy controls received a single twenty-minute-long session of modulated monophasic scTS delivered over the T5 and T10 spinal cord segments. Forced vital capacity (FVC), peak forced inspiratory flow (PIF), peak expiratory flow (PEF), time-to-peak of inspiratory flow (tPIF), and time-to-peak of expiratory flow (tPEF), as indirect measures of spinal motor network activity, were assessed before and after the intervention. Results: In the COVID-19 group, the scTS intervention led to significantly increased PIF (p = 0.040) and PEF (p = 0.049) in association with significantly decreased tPIF (p = 0.035) and tPEF (p = 0.013). In the control group, the exposure to scTS also resulted in significantly increased PIF (p = 0.010) and significantly decreased tPIF (p = 0.031). Unlike the results in the COVID-19 group, the control group had significantly decreased PEF (p = 0.028) associated with significantly increased tPEF (p = 0.036). There were no changes for FVC after scTS in both groups (p = 0.67 and p = 0.503). Conclusions: In post-COVID-19 patients, scTS facilitates excitation of both inspiratory and expiratory spinal neural networks leading to an immediate improvement of respiratory functional performance. This neuromodulation approach could be utilized in rehabilitation programs for patients with COVID-19 respiratory deficits.
Influence of Ion Nitriding on Microstructure and Properties of Haynes 282 Nickel Superalloy Specimens Produced Using DMLS Technique
Authors: Sitek Ryszard , Kulikowski Krzysztof , Paradowski Krystian , Gancarczyk Kamil , Losertová Monika , Kobayashi Akira , Moneta Joanna , Kamiński Janusz
Published: July 2023

The paper investigates the influence of the ion-nitriding process on the microstructure, corrosion resistance, and tensile strength at elevated temperatures of Haynes 282 nickel superalloy specimens produced by the Direct Metal Laser Sintering (DMLS) technique. The study was performed for two conditions, i.e., as-built by DMLS method and as-built by DMLS method + covered by a layer containing CrN + Cr2N phases. An analysis of the surface morphology revealed that the ion-nitriding process significantly affects the physical and chemical phenomena occurring on the specimen’s surface. The XRD measurement of the specimens showed that preparing them with the DMLS method as well as following a nitriding process produced residual tensile stresses. Based on the measurement of the nanohardness distribution through the layer approximatively of 7 μm in width and the superalloys substrate, the results of the nanohardness showed the maximum values of 27 GPa and 13.5 GPa for the nitrided layer and the substrate, respectively. The surface protection from the nitrided layer proved a positive effect on the corrosion resistance of the DMLS specimens in the solution of 0.1 M Na2SO4 + 0.1 M NaCl at room temperature. The results of the tensile tests at 750 °C showed that the ion-nitriding process did not significantly affect the elevated-temperature tensile strength of the superalloy specimens produced with the DMLS technique.
Electrochemical Performance of Corn Waste Derived Carbon Electrodes Based on the Intrinsic Biomass Properties
Authors: Xie Kunhan , Zhang Wen , Ren Kai , Zhu Enze , Lu Jianyi , Chen Jingyang , Yin Penggang , Yang Liu , Guan Xiaohui , Wang Guangsheng
Published: July 2023

The exploration of cost-effective and sustainable biomass-derived carbon materials as electrodes for energy conversion and storage has gained extensive attention in recent research studies. However, the selection of the biomass and the electrochemical performance regulation of the derived biochar, as well as their interrelationship still remain challenging for practical application. Herein, corn wastes with high carbon content (>40%), corn cob and corn silk, were selected as precursors for the preparation of high value-added and high yield carbon materials via a modified synthetic process. Uniquely, this work put emphasis on the theoretical and experimental investigations of how the biomass properties influence the composition and nanostructure regulation, the electrolyte ion adsorption free energy, and the electrical conductivity of the derived carbon materials as well as their electrochemical performance optimization. Owing to the favorable specific surface area, the hierarchical porous structure, and the diverse elemental distribution, corn cob and corn silk derived carbon materials (CBC and SBC) present great potential as promising electrodes for alkaline aqueous zinc batteries and supercapacitors. The assembled CBC//Zn and SBC//Zn zinc batteries deliver high energy densities of 63.0 Wh kg−1 and 39.1 Wh kg−1 at a power density of 575 W kg−1, with excellent cycling performance of 91.1% and 84.3% capacitance retention after 10,000 cycles. As for the assembled symmetric supercapacitors, high energy densities of 14.9 Wh kg−1 and 13.6 Wh kg−1, and superior long-term cycling stability of 99.3% and 96.6% capacitance retention after 20,000 cycles could be achieved. This study highlights the advantages of utilizing corn cob and corn silk as carbon sources on the designed synthesis of carbon electrodes, and presents a meaningful perspective in the investigation of biomass-derived carbon materials and their potential applications in rechargeable devices.
Antimicrobial Solutions for Endotracheal Tubes in Prevention of Ventilator-Associated Pneumonia
Authors: Marcut Lavinia , Manescu (Paltanea) Veronica , Antoniac Aurora , Paltanea Gheorghe , Robu Alina , Mohan Aurel George , Grosu Elena , Corneschi Iuliana , Bodog Alin Danut
Published: July 2023

Ventilator-associated pneumonia is one of the most frequently encountered hospital infections and is an essential issue in the healthcare field. It is usually linked to a high mortality rate and prolonged hospitalization time. There is a lack of treatment, so alternative solutions must be continuously sought. The endotracheal tube is an indwelling device that is a significant culprit for ventilator-associated pneumonia because its surface can be colonized by different types of pathogens, which generate a multispecies biofilm. In the paper, we discuss the definition of ventilator-associated pneumonia, the economic burdens, and its outcomes. Then, we present the latest technological solutions for endotracheal tube surfaces, such as active antimicrobial coatings, passive coatings, and combinatorial methods, with examples from the literature. We end our analysis by identifying the gaps existing in the present research and investigating future possibilities that can decrease ventilator-associated pneumonia cases and improve patient comfort during treatment.
Experimental Research on the Bond Performance between SMAF-ECC Composites and Steel Bar
Authors: Yang Zhao , Li Shuai , Gao Feng , Wang Rui
Published: July 2023

Combining Engineered Cementitious Composites (ECC) with shape memory alloy (SMA) fibers can form SMA fiber reinforced ECC (SMAF-ECC) that has excellent deformation recovery and energy dissipation capabilities. Substituting some of the tensioned concrete with this new composite material, along with steel bars, is expected to significantly improve the seismic energy dissipation and self-recovery capabilities of traditional reinforced concrete components. However, a reliable bond between steel bars and SMAF-ECC is critical to ensure their synergistic performance. In this paper, the failure mode and bond strength of steel bars and SMAF-ECC were studied through direct tensile tests, and the influence factors such as steel bar diameter, bond length, and SMAF volume fraction were analyzed. A bond-slip constitutive model for steel bars and SMAF-ECC was proposed. The results show that the failure mode of the tensile test specimens is mainly steel bar pull-out failure; the incorporation of SMAF significantly enhances the bond strength between the steel bar and matrix; increasing the steel bar diameter and bond length both lead to a decrease in bond strength while increasing the SMAF volume fraction can significantly increase the bond strength. Among them, the specimen with a steel bar diameter of 12 mm, bond length of 70 mm, and SMAF volume fraction of 0.5% has the largest increase in bond strength, reaching 52.96%. The proposed improved bond-slip constitutive model is in good agreement with the bond-slip curve obtained in the experiments, with a determination coefficient of 0.99. The research results of this paper provide an important theoretical basis for promoting the engineering application of SMAF-ECC materials.
A Reliable Life Consumption Assessment and Individual Life Monitoring Method for Rolling Bearings
Authors: Fu Yueshuai , Fu Huimin , Wu Qiong
Published: July 2023

Rolling bearings are critical rotating components in aerospace and high-speed trains. The service loads of rolling bearings are generally different from each other, causing significant differences in their damage degrees and reliable life potential. To ensure bearing reliability during service, a reliable life consumption assessment and individual life monitoring method is proposed. Firstly, a small-sample reliable life evaluation method is established based on an accelerated life test conducted at a constant load or load block spectrum before delivery, by which the lower confidence limit of the reliable life of the rolling bearing under any service load can be calculated with the required confidence and reliability. Then, the confidence limits of the reliable life consumption percentage and remaining reliable life percentage for each rolling bearing can be evaluated in real time according to their online monitoring loads and Miner’s law. By this means, individual life monitoring and online life management can be conveniently realized. Compared with traditional bearing life management methods, which do not consider service load differences, this method can more effectively ensure service safety and simultaneously maximize the life potential of bearings.
Enhancing Decomposition Approach for Solving Multi-Objective Dynamic Non-Linear Programming Problems Involving Fuzziness
Authors: Kumar Pavan , Khalifa Hamiden Abd El-Wahed
Published: July 2023

In real-life scenarios, there are many mathematical tools to handle incomplete and imprecise data. One of them is the fuzzy approach. The main issue with addressing nonlinear interval programming (NIP) problems is that the optimal solution to the problem is a decision made under uncertainty that has a risk of not satisfying the feasibility and optimality criteria. Some strategies handle this kind of problem using classical terminology such as optimal solution and feasible solution. These strategies are insufficient for efficient analysis since the properties of the solution in an uncertain environment are ignored. Therefore, in the proposed approach, more suitable terminologies were suggested for the analysis process. In addition, it combines parametric treatment and interactive methodology. This article aims to contribute to the literature of fuzzy multi-objective dynamic programming (MODP) issues involving the fuzzy objective functions. The piecewise quadratic fuzzy numbers characterize these fuzzy parameters. Some basic notions in the problem under the α-pareto optimal solution concept is redefined and analyzed to study the stability of the problem. Furthermore, a technique, named the decomposition approach (DP), is presented for achieving a subset for the parametric space that contains the same α-pareto optimal solution. For a better understanding of the suggested concept, a numerical example is provided.
Global-Local Dynamic Adversarial Learning for Cross-Domain Sentiment Analysis
Authors: Lyu Juntao , Zhang Zheyuan , Chen Shufeng , Fan Xiying
Published: July 2023

As one of the most widely used applications in domain adaption (DA), Cross-domain sentiment analysis (CDSA) aims to tackle the barrier of lacking in sentiment labeled data. Applying an adversarial network to DA to reduce the distribution discrepancy between source and target domains is a significant advance in CDSA. This adversarial DA paradigm utilizes a single global domain discriminator or a series of local domain discriminators to reduce marginal or conditional probability distribution discrepancies. In general, each discrepancy has a different effect on domain adaption. However, the existing CDSA algorithms ignore this point. Therefore, in this paper, we propose an effective, novel and unsupervised adversarial DA paradigm, Global-Local Dynamic Adversarial Learning (GLDAL). This paradigm is able to quantitively evaluate the weights of global distribution and every local distribution. We also study how to apply GLDAL to CDSA. As GLDAL can effectively reduce the distribution discrepancy between domains, it performs well in a series of CDSA experiments and achieves improvements in classification accuracy compared to similar methods. The effectiveness of each component is demonstrated through ablation experiments on different parts and a quantitative analysis of the dynamic factor. Overall, this approach achieves the desired DA effect with domain shifts.
A Simplified Model for the On-Line Identification of Bearing Direct-Dynamic Parameters Based on Algebraic Identification (AI)
Authors: Landa-Damas Saulo Jesús , Colín-Ocampo Jorge , Blanco-Ortega Andrés , Abúndez-Pliego Arturo , Mendoza-Larios José Gabriel , Baltazar-Tadeo Luis Alberto , Pérez-Vigueras Demetrio
Published: July 2023

In this paper, a mathematical model is presented to identify the direct dynamic coefficients (kxx, kzz, cxx, czz) of a pressurized bearing in a rotor-bearing system. The presented mathematical model for online identification is the result of the application of the algebraic identification approach to a two-degree-of-freedom rotor-bearing model. The proposed identification model requires only the vibration response as the input data. The performance of the model was assessed by theoretically and experimentally testing the proposed identifier at different shaft frequencies and, for the experimental test, a pressurized bearing that has hydrodynamic and hydrostatic characteristics at a support pressure of 10 psi was considered. The working fluid is Chevron GST 32 oil. The results show negligible differences between the vibration response of the experimental rotor and those obtained numerically using the identified direct dynamic coefficients of the pressurized bearing. In addition, it is observed that the algebraic identifier determines the identified parameters in a time less than 0.2 s. The proposed identifier can be used in other types of bearings, which is a great advantage over other identifiers.
An Efficient Numerical Approach for Solving Systems of Fractional Problems and Their Applications in Science
Authors: Syam Sondos M. , Siri Z. , Altoum Sami H. , Kasmani R. Md.
Published: July 2023

In this article, we present a new numerical approach for solving a class of systems of fractional initial value problems based on the operational matrix method. We derive the method and provide a convergence analysis. To reduce computational cost, we transform the algebraic problem produced by this approach into a set of 2×2 nonlinear equations, instead of solving a system of 2 m × 2 m equations. We apply our approach to three main applications in science: optimal control problems, Riccati equations, and clock reactions. We compare our results with those of other researchers, considering computational time, cost, and absolute errors. Additionally, we validate our numerical method by comparing our results with the integer model when the fractional order approaches one. We present numerous figures and tables to illustrate our findings. The results demonstrate the effectiveness of the proposed approach.
Asymptotic Diffusion Method for Retrial Queues with State-Dependent Service Rate
Authors: Nazarov Anatoly , Fedorova Ekaterina , Lizyura Olga , Salimzyanov Radmir
Published: July 2023

In this paper, we consider a retrial queue with a state-dependent service rate as a mathematical model of a node of FANET communications. We suppose that the arrival process is Poisson, the delay duration is exponentially distributed, the orbit is unlimited, and there is multiple random access from the orbit. There is one server, and the service time of every call is distributed exponentially with a variable parameter depending on the number of calls in the orbit. The service rate has an infinite number of values. We propose the asymptotic diffusion method for the model study. The asymptotic diffusion approximation of the probability distribution of the number of calls in the orbit is derived. Some numerical examples are demonstrated.
Triggering the Amphotericin B Pore-Forming Activity by Phytochemicals
Authors: Efimova Svetlana S. , Malykhina Anna I. , Ostroumova Olga S.
Published: July 2023

The macrolide polyene antibiotic amphotericin B (AmB), remains a valuable drug to treat systemic mycoses due to its wide antifungal activity and low probability of developing resistance. The high toxicity of AmB, expressed in nephropathy and hemolysis, could be partially resolved by lowering therapeutic AmB concentration while maintaining efficacy. This work discusses the possibility of using plant polyphenols and alkaloids to enhance the pore-forming and consequently antifungal activity of AmB. We demonstrated that phloretin, phlorizin, naringenin, taxifolin, quercetin, biochanin A, genistein, resveratrol, and quinine led to an increase in the integral AmB-induced transmembrane current in the bilayers composed of palmitoyloleoylphosphocholine and ergosterol, while catechin, colchicine, and dihydrocapsaicin did not practically change the AmB activity. Cardamonin, 4′-hydroxychalcone, licochalcone A, butein, curcumin, and piperine inhibited AmB-induced transmembrane current. Absorbance spectroscopy revealed no changes in AmB membrane concentration with phloretin addition. A possible explanation of the potentiation is related to the phytochemical-produced changes in the elastic membrane properties and the decrease in the energy of formation of the lipid mouth of AmB pores, which is partially confirmed by differential scanning microcalorimetry. The possibility of AmB interaction with cholesterol in the mammalian cell membranes instead of ergosterol in fungal membranes, determines its high toxicity. The replacement of ergosterol with cholesterol in the membrane lipid composition led to a complete loss or a significant decrease in the potentiating effects of tested phytochemicals, indicating low potential toxicity of these compounds and high therapeutic potential of their combinations with the antibiotic. The discovered combinations of AmB with plant molecules that enhance its pore-forming ability in ergosterol-enriched membranes, seem to be promising for further drug development in terms of the toxicity decrease and efficacy improvement.
Mesoporous SiC-Based Photocatalytic Membranes and Coatings for Water Treatment
Authors: Cervantes-Diaz Karla Begonia , Drobek Martin , Julbe Anne , Ayral André , Cambedouzou Julien
Published: July 2023

Photocatalytically active silicon carbide (SiC)-based mesoporous layers (pore sizes between 5 and 30 nm) were synthesized from preceramic polymers (polymer-derived ceramic route) on the surface and inside the pores of conventional macroporous α-alumina supports. The hybrid membrane system obtained, coupling the separation and photocatalytical properties of SiC thin films, was characterized by different static and dynamic techniques, including gas and liquid permeation measurements. The photocatalytic activity was evaluated by considering the degradation efficiency of a model organic pollutant (methylene blue, MB) under UV light irradiation in both diffusion and permeation modes using SiC-coated macroporous supports. Specific degradation rates of 1.58 × 10−8 mol s−1 m−2 and 7.5 × 10−9 mol s−1 m−2 were obtained in diffusion and permeation modes, respectively. The performance of the new SiC/α-Al2O3 materials compares favorably to conventional TiO2-based photocatalytic membranes, taking advantage of the attractive physicochemical properties of SiC. The developed synthesis strategy yielded original photocatalytic SiC/α-Al2O3 composites with the possibility to couple the ultrafiltration SiC membrane top-layer with the SiC-functionalized (photocatalytic) macroporous support. Such SiC-based materials and their rational associations on porous supports offer promising potential for the development of efficient photocatalytic membrane reactors and contactors for the continuous treatment of polluted waters.
Thermally Activated Crack Growth and Fracture Toughness Evaluation of Pipeline Steels Using Acoustic Emission
Authors: Perveitalov Oleg G. , Nosov Viktor V. , Schipachev Andrey M. , Alekhin Alexey I.
Published: July 2023

The article presents an approach to assessing the fracture toughness of structural alloys based on thermally activated crack growth and recording acoustic emission signals. The kinetic and structural features of the stable growth of the initiated crack are estimated using a multilevel acoustic emission model based on the time dependence of the logarithm of the cumulative acoustic emission count. The article provides an evaluation of the stable kinetic constants included in the equation of the thermal fluctuation steps of a crack according to literature sources and using the acoustic emission method. It is shown that parameters such as activation energy, activation area before the crack tip, and the rate of non-activation crack growth are stable and show a satisfactory correspondence between the reference literature and real experiments. The approach does not require a set of laboratory experiments to determine the empirical constants of traditional crack growth rate equations, and it also differs in that it takes into account the unique features of the destruction of a particular specimen or technological equipment and allows for a non-destructive assessment of fracture toughness. The values obtained are conservative. The concentration criterion of destruction requires further investigation.
Modification of Microstructure and Mechanical Parameters of Austenitic Steel AISI 316L under the Action of Low Friction
Authors: Grabco Daria , Shikimaka Olga , Pyrtsac Constantin , Topal Daria , Vilotic Dragisa , Vilotic Marko , Alexandrov Sergei
Published: July 2023

This work is devoted to the study of the tribological properties of AISI 316L austenitic steel and the effect of the relative velocity of rubbing bodies on the microstructure and mechanical properties. The specificity of the deformation is investigated in the mode of dry friction “metal/metal”, namely, steel AISI 316L/steel St3sp, with a process duration of 15 h. The change in the microstructure of the samples as a result of friction and the determination of mechanical properties are carried out on the friction surface and on the cross-section of the samples. The mechanical parameters are studied by depth-sensitive indentation using a Berkovich indenter. It is shown that low friction with the relative velocity of rubbing bodies of about 30 rpm is capable of introducing noticeable microstructural and strength changes. Strength and relaxation properties (hardness, Young’s modulus, plasticity index, and resistance index) increase in samples subjected to friction compared to the original undeformed sample. A change in the microscopic structure of the samples near the friction surface increases such material properties as microhardness (H) and Young’s modulus (E). In particular, the microhardness increases from 1.72 GPa for the undeformed sample to 3.5 GPa for the sample subjected to friction for 15 h. Young’s modulus increases from 107 GPa to 140 GPa, respectively. A comparison with the properties of samples deformed at the relative velocity of rubbing bodies of about 300 rpm shows a further increase in the microhardness and Young’s modulus. Also noted is the sensitivity of the relaxation parameters to the friction process and the relative velocity of rubbing bodies. In particular, the relaxation parameters hc and hres decrease while he-p increases.
Metabolomics and Self-Reported Depression, Anxiety, and Phobic Symptoms in the VA Normative Aging Study
Authors: Prince Nicole , Stav Meryl , Cote Margaret , Chu Su H. , Vyas Chirag M. , Okereke Olivia I. , Palacios Natalia , Litonjua Augusto A , Vokonas Pantel , Sparrow David , Spiro Avron , Lasky-Su Jessica A. , Kelly Rachel S.
Published: July 2023

Traditional approaches to understanding metabolomics in mental illness have focused on investigating a single disorder or comparisons between diagnoses, but a growing body of evidence suggests substantial mechanistic overlap in mental disorders that could be reflected by the metabolome. In this study, we investigated associations between global plasma metabolites and abnormal scores on the depression, anxiety, and phobic anxiety subscales of the Brief Symptom Inventory (BSI) among 405 older males who participated in the Normative Aging Study (NAS). Our analysis revealed overlapping and distinct metabolites associated with each mental health dimension subscale and four metabolites belonging to xenobiotic, carbohydrate, and amino acid classes that were consistently associated across all three symptom dimension subscales. Furthermore, three of these four metabolites demonstrated a higher degree of alteration in men who reported poor scores in all three dimensions compared to men with poor scores in only one, suggesting the potential for shared underlying biology but a differing degree of perturbation when depression and anxiety symptoms co-occur. Our findings implicate pathways of interest relevant to the overlap of mental health conditions in aging veterans and could represent clinically translatable targets underlying poor mental health in this high-risk population.
Chemical Constituents of Euphorbia stracheyi Boiss (Euphorbiaceae)
Authors: Zhu Hui , Ren Xiangxiang , Huang Yanbo , Su Tao , Yang Lei
Published: July 2023

Euphorbia stracheyi Boiss was used for hemostasis, analgesia, and muscular regeneration in traditional Chinese medicine. To study the chemical constituents of E. stracheyi, the ethyl acetate part of the methanol extract of the whole plant was separated by silica gel, sephadex LH-20 column chromatography, and semi-preparative HPLC. The isolation led to the characterization of a new lathyrane type diterpenoid, euphostrachenol A (1), as well as eleven known compounds (2–11), including a lathyrane, three ingenane-type and two abietane-type diterpenoids, two ionones, and two flavonoids. The structures of these compounds were established using 1D- and 2D-NMR experiments, mass spectrometry, and X-ray crystallographic experiments. The MTT method was used to determine the cytotoxic activity of five cancer cell lines (Leukemia HL-60, lung cancer A-549, liver cancer SMMC-7721, breast cancer MCF-7, and colon cancer SW480) on the isolated compounds. However, only compound 4 showed moderate cytotoxicity against these cell lines, with IC50 values ranging from 10.28 to 29.70 μM, while the others were inactive. Our chemical investigation also confirmed the absence of jatrophane-type diterpenoids in the species, which may be related to its special habitat.
Red Blood Cell Partitioning Using a Microfluidic Channel with Ladder Structure
Authors: Hyakutake Toru , Tsutsumi Yuya , Miyoshi Yohei , Yasui Manabu , Mizuno Tomoki , Tateno Mizuki
Published: July 2023

This study investigated the partitioning characteristics of red blood cells (RBCs) within capillaries, with a specific focus on ladder structures observed near the end of the capillaries. In vitro experiments were conducted using microfluidic channels with a ladder structure model comprising six bifurcating channels that exhibited an anti-parallel flow configuration. The effects of various factors, such as the parent channel width, distance between branches, and hematocrit, on RBC partitioning in bifurcating channels were evaluated. A decrease in the parent channel width resulted in an increase in the heterogeneity in the hematocrit distribution and a bias in the fractional RBC flux. Additionally, variations in the distance between branches affected the RBC distribution, with smaller distances resulting in greater heterogeneity. The bias of the RBC distribution in the microchannel cross section had a major effect on the RBC partitioning characteristics. The influence of hematocrit variations on the RBC distribution was also investigated, with lower hematocrit values leading to a more pronounced bias in the RBC distribution. Overall, this study provides valuable insights into RBC distribution characteristics in capillary networks, contributing to our understanding of the physiological mechanisms of RBC phase separation in the microcirculatory system. These findings have implications for predicting oxygen heterogeneity in tissues and could aid in the study of diseases associated with impaired microcirculation.
Valveless On-Chip Aliquoting for Molecular Diagnosis
Authors: Romero Deza Andersson A. , Schaumburg Federico , Berli Claudio L. A.
Published: July 2023

The detection of nucleic acids as specific markers of infectious diseases is commonly implemented in molecular biology laboratories. The translation of these benchtop assays to a lab-on-a-chip format demands huge efforts of integration and automation. The present work is motivated by a strong requirement often posed by molecular assays that combine isothermal amplification and CRISPR/Cas-based detection: after amplification, a 2–8 microliter aliquot of the reaction products must be taken for the subsequent reaction. In order to fulfill this technical problem, we have designed and prototyped a microfluidic device that is able to meter and aliquot in the required range during the stepped assay. The operation is achieved by integrating a porous material that retains the desired amount of liquid after removing the excess reaction products, an innovative solution that avoids valving and external actuation. The prototypes were calibrated and experimentally tested to demonstrate the overall performance (general fluidics, metering, aliquoting, mixing and reaction). The proposed aliquoting method is fully compatible with additional functions, such as sample concentration or reagent storage, and could be further employed in alternative applications beyond molecular diagnosis.
Evaluation of Gut Microbiota in Healthy Persons and Type 1 Diabetes Mellitus Patients in North-Western Russia
Authors: Chukhlovin Alexei B. , Dudurich Vasilisa V. , Kusakin Aleksey V. , Polev Dmitry E. , Ermachenko Ekaterina D. , Aseev Mikhail V. , Zakharov Yuri A. , Eismont Yuri A. , Danilov Lavrentii G. , Glotov Oleg S.
Published: July 2023

Bacterial microbiota in stool may vary over a wide range, depending on age, nutrition, etc. The purpose of our work was to discriminate phyla and genera of intestinal bacteria and their biodiversity within a healthy population (North-Western Russia) compared to the patients with type 1 diabetes mellitus (T1DM). The study group included 183 healthy persons 2 to 53 years old (a mean of 26.5±1.0 years old), and 41 T1DM patients (mean age 18.2±1.8 years old). The disease onset was at 11±1.5 years, with a T1DM experience of 7±1.5 years. Total DNA was isolated from the stool samples, and sequencing libraries were prepared by amplifying the V3–V4 region of the 16S rRNA gene sequenced by Illumina MiSeq. Bioinformatic processing of NGS databases was adapted for microbiota evalutaion. Despite the broad scatter, the biological diversity for bacterial microbiota expressed as the Shannon index was significantly increased from younger to older ages in the comparison group, higher in adult healthy persons, with a trend for decrease in the Actinomycetota phylum which includes Bifidobacterium longum species. Similar but non-significant age trends were noted in the T1DM group. Concordant with the Bacillota prevalence in stool samples of diabetic patients, some anaerobic bacteria (Faecalibacteria, Lachnospira and Ruminococcae, Roseburia) were enriched in the T1DM microbiome against controls. Hence, correction of microbiota for Ruminococcus and Lachnospiraceae requires future search for new probiotics. Lower abundance of Actinomycetota and Bifidobacter in T1DM suggests potential usage of Bifidobacter-based probiotics in this cohort.
The Mechanism of Antimicrobial Activity of Conjugated Bile Acids against Lactic Acid Bacilli
Authors: Chai Li-Na , Wu Hua , Wang Xue-Jiao , He Li-Juan , Guo Chun-Feng
Published: July 2023

The mechanism underlying antimicrobial activity of conjugated bile acids against strains of lactic acid bacilli is not well understood. The purpose of this study was to investigate two typical conjugated bile acids (glycochenodeoxycholic acid and taurochenodeoxycholic acid) for their mechanisms of antimicrobial activity against four strains of different species of lactic acid bacilli at the physiological pH of the small intestine of humans. The bacterial cell membrane integrity, transmembrane potential, and transmembrane pH gradient were examined using the fluorescence probes SYTO 9 plus propidium iodide, 3,3′-dipropylthiadicarbocyanine iodide, and 5(6)-carboxyfluorescein diacetate N-succinimidyl ester, respectively. The intracellular ATP levels were measured by the firefly luciferase-based bioluminescence method. It was found that the antimicrobial activity of conjugated bile acids against the strains of lactic acid bacilli is strain-specific, and glycochenodeoxycholic acid showed significantly greater antimicrobial activity than taurochenodeoxycholic acid against the strains of lactic acid bacilli. The conjugated bile acids inhibited the growth of strains of lactic acid bacilli by disrupting membrane integrity, dissipating transmembrane potential, reducing the transmembrane pH gradient, and depleting intracellular ATP. In conclusion, the antimicrobial activity of conjugated bile acids against lactic acid bacilli is a multifactorial phenomenon. This study will provide valuable information for developing strategies to improve the ability of lactic acid bacilli to tolerate bile in vivo.
Characteristics and Evolution of Tectonic Fractures in the Jurassic Lianggaoshan Formation Shale in the Northeast Sichuan Basin
Authors: Bai Xuefeng , Wang Xiandong , Wang Zhiguo , Deng Hucheng , Li Yong , Li An , Cao Hongxiu , Wang Li , Zhu Yanping , Lu Shuangfang , Cao Feng , He Jianhua
Published: July 2023

The features and formation stages of natural fractures have significant influences on the fracturing of shale reservoirs and the accumulation of oil and gas. The characteristics and evolution of tectonic fractures in the Lianggaoshan Formation in Northeast Sichuan were investigated based on outcrops, drill cores, geochemical data, and acoustic emission test results. Our results demonstrated that the fracture types of the Lianggaoshan Formation were mainly low-degree bedding-slip fractures, followed by high-degree through-strata shear fractures and vertical tensile fractures. The influences of strike-slip faults on the fractures were stronger than those of thrust faults; fractures in thrust faults were concentrated in the hanging wall. The densities of tensile and shear fractures were inversely proportional to the formation thickness, while the density of interlayer slip fractures was independent of the formation thickness. The density of tectonic fractures was proportional to the quartz content. The fractures of the Lianggaoshan Formation were generated in three stages during uplift: (1) Late Yanshan–Early Himalayan tectonic movement (72~55 Ma), (2) Middle Himalayan tectonic movement (48~32 Ma), (3) Late Himalayan tectonic movement (15 Ma~4 Ma). Fractures greatly improve the oil and gas storage capacity and increase the contents of free and total hydrocarbons. At the same time, they also reduce the breakdown pressure of strata. This study facilitated the prediction of the fracture distribution and oil and gas reservoirs in the Lianggaoshan Formation and provided references for the selection of favourable areas for shale oil and the evaluation of desert sections in the study area.
Genesis of Pyrite in Clastic Rocks of Deep Salt-Related Strata in the Simao Basin and Its Implication for Potash Mineralization: A Case Study of the Well MK-3
Authors: Miao Zhongying , Zheng Mianping , Lou Pengcheng , Xu Qihui , Liu Yuanying
Published: July 2023

In depth of the Simao Basin (2390 to 2650 m depth interval), many gray mudstone or carbonate rocks are developed in the red salt-related strata, and pyrite crystals are found in the fissure and matrix. In this study, petrology, mineralogy, element geochemistry, and LA-MC-ICP-MS in situ sulfur isotope analysis were used to constrain the genesis of pyrite, and the influence of relevant geological activities on potash mineralization was discussed. The results show that: (1) In the upper part of the salt layer, particle size of the pyrite ranges from 50 to 300 μm. The crystal morphology is mainly pentagonal-dodecahedral and irregularly granular, with a small amount of cuboidal pyrite. In the interlayer between rock salt, particle size of the pyrite is from 50 to 100 μm, and the crystals are mainly octahedral. (2) The S/Fe value of pentagonal-dodecahedral pyrite is significantly greater than 2; the S/Fe value of octahedral and cubic pyrite is less than 2; and the S/Fe value of irregular granular pyrite is close to 2. (3) The δ34SV-CDT values of pyrite in the upper salt-related strata range from −15.65‰ to 11.81‰, and the average δ34SV-CDT values of all samples range from 0.79‰ to 8.20‰. The δ34SV-CDT values of pyrite interlayer between rock salt range from −15.02‰ to −6.36‰, with an average value of −10.66‰. The above results indicate that the pyrite in the upper part of the rock salt layer was formed in a medium-low temperature hydrothermal environment, and the ore-forming sulfur elements have hydrothermal sources, bacterial sulfate reduction (BSR) sources, and thermochemical sulfate reduction (TSR) contributions. The pyrite between the rock salt layers is of sedimentary origin, and the ore-forming sulfur element comes from BSR. At present, there is no evidence of the influence of hydrothermal activities on deep potash-rich salt bodies, and the influence on the Mengyejing potash deposit has continued since the metallogenic period.
Modelling of a Post-Mining Catchment for Future Simulations
Authors: Nair Devika , Evans K. G. , Bellairs Sean
Published: July 2023

Landform evolution modelling (LEM) provides an avenue for simulating how a landscape may evolve over extended time periods of thousands of years. CAESAR-Lisflood LEM which includes a hydrologic model (TOPMODEL) and a hydraulic model (Lisflood) can be used to assess the proposed final landform morphology of a mine site by simulating how the mine landform and the landscape would evolve over a 1000-year period. The accuracy of future simulations depends on the calibration and validation of the model to past and present events. Calibration and validation of the model involve finding a combination of parameters of the model which when applied and simulated gives model outputs similar to those observed for the real site scenario for corresponding input data. Calibrating the sediment output of the CAESAR-Lisflood model at the catchment level and using it for studying the equilibrium conditions of the landform is an area that has yet to be explored. Therefore, the aim of this study was to calibrate the CAESAR-Lisflood model and then validate it. To achieve this, the model was run for a rainfall event with a set of parameters, plus discharge and sediment data for the input point of the catchment, to analyse how similar the model output would behave when compared with the discharge and sediment data for the output point of the catchment. The model parameters were then adjusted until the model closely approximated the real site values of the catchment. The model was then validated by running it for a different set of events and checking that the model gave similar results to the real site values. The outcomes demonstrated that while the model can be calibrated to a greater extent for hydrology (discharge output) throughout the year, sediment output calibration may be slightly improved via the ability to change parameters to take into account the seasonal vegetation growth during the start and end of the wet season. This study is important for designing and testing post-mining rehabilitated landscape systems that assess hydrology and sediment movement in seasonal biomes.
Investigation on the Mechanism of PAL (100) Surface Modified by APTES
Authors: Jia Weimin , Qi Bomiao , Wang Yanbin , Lu Zhibin , Wang Jiqian , Su Qiong , Nian Jingyan , Liang Junxi
Published: July 2023

The interfacial mechanism has always been a concern for 3-aminopropyltriethoxysilane (APTES)-grafted palygorskite (PAL). In this research, the mechanism of graft modification for grafting of APTES to the surface of PAL (100) was studied using density functional theory (DFT) calculation. The results illustrated that different grafting states of the APTES influence the inter- and intramolecular interactions between APTES/PAL (100), which are reflected in the electronic structures. For single-, double-, and three-toothed state APTES-PAL (100), the charge transfer rates from the PAL (100) surface to APTES were 0.68, 1.02, and 0.77 e, respectively. The binding energy results show that PAL (100) modification performance in the double-tooth state is the best compared to the other states, with the lowest value of −181.91 kJ/mol. The double-toothed state has lower barrier energy (94.69, 63.11, and 153.67 kJ/mol) during the modification process. This study offers theoretical insights into the chemical modification of the PAL (100) surface using APTES coupling agents, and can provide a guide for practical applications.