bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrodynamic Forces and Wake Distribution of Various Ship Shapes Calculated Using a Reynolds Stress Model
Authors: Matsuda Satoshi , Katsui Tokihiro
Published: June 2022

The Reynolds-averaged Navier–Stokes (RANS)-based computational fluid dynamics (CFD) calculation using a two-equation turbulence model, such as the k–omega shear-stress transport (SST) model, is a mainstream method with sufficient accuracy for the estimation of integral hydrodynamic forces and moment at both the model-scale and full scale. This paper confirmed that the Reynolds stress model (RSM) has sufficient estimation accuracy of viscous resistance and wake distribution at the hull design stage. Herein, the ability of RSMs to estimate the viscous resistance and wake distribution of a JBC ship is evaluated. Specifically, the verification and validation (V&V) method is employed to indicate the numerical and model uncertainties of each turbulence model used to estimate the viscous resistance. The RSMs showed higher numerical uncertainty than the k–omega SST. However, the uncertainty of the experimental measurements is generally smaller than the numerical uncertainty. Moreover, the linear pressure–strain (LPS) and the linear pressure–strain two-layer (LPST) models show less comparison error of the viscous resistance than the k–omega SST. Furthermore, the LPST and k–omega SST models are applied to twenty ships with various full and fine hull forms to calculate the viscous resistance and compare it with the experimental results. The viscous resistance of the LPST model showed a small difference when employed in experimental fluid dynamics (EFD) and CFD calculations. Using the LPST model, the viscous resistance can be estimated with high accuracy in our setting. For industrial use, this study could provide an important insight into the designing of various types of vessels.
Stem Cell Biomarkers and Tumorigenesis in Gastric Cancer
Authors: Wuputra Kenly , Ku Chia-Chen , Pan Jia-Bin , Liu Chung-Jung , Liu Yi-Chang , Saito Shigeo , Kato Kohsuke , Lin Ying-Chu , Kuo Kung-Kai , Chan Te-Fu , Chong Inn-Wen , Lin Chang-Shen , Wu Deng-Chyang , Yokoyama Kazunari K.
Published: June 2022

Stomach cancer has a high mortality, which is partially caused by an absence of suitable biomarkers to allow detection of the initiation stages of cancer progression. Thus, identification of critical biomarkers associated with gastric cancer (GC) is required to advance its clinical diagnoses and treatment. Recent studies using tracing models for lineage analysis of GC stem cells indicate that the cell fate decision of the gastric stem cells might be an important issue for stem cell plasticity. They include leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5+), Cholecystokinin receptor 2 (Cckr2+), and axis inhibition protein 2 (Axin2+) as the stem cell markers in the antrum, Trefoil Factor 2 (TFF2+), Mist1+ stem cells, and Troy+ chief cells in the corpus. By contrast, Estrogen receptor 1 (eR1), Leucine-rich repeats and immunoglobulin-like domains 1 (Lrig1), SRY (sex determining region Y)-box 2 (Sox2), and B lymphoma Mo-MLV insertion region 1 homolog (Bmi1) are rich in both the antrum and corpus regions. These markers might help to identify the cell-lineage identity and analyze the plasticity of each stem cell population. Thus, identification of marker genes for the development of GC and its environment is critical for the clinical application of cancer stem cells in the prevention of stomach cancers.
The Culture-Centered Development Potential of Communities in Făgăraș Land (Romania)
Authors: Sorea Daniela , Csesznek Codrina , Rățulea Gabriela Georgeta
Published: June 2022

Făgăraș Land (Romania) is a very old administrative formation with its own identity, preserved from the beginning of the Middle Ages. The mapping of the intangible cultural heritage (ICH) highlighted the groups of caroling lads as the main strategic heritage resource, but also the existence of many other ICH resources that can be exploited towards the sustainable development of the area. These include local soups, an ICH gastronomic resource that can help build the area’s tourism brand. All resources, together with the peculiarities of the local medieval history, the memory of the anti-communist resistance in the Făgăraș Mountains and the religious pilgrimage to the local Orthodox monasteries, support the configuration of Făgăraș Land as a multidimensional associative cultural landscape. The content analysis of the information on ICH available on the official websites of the administrative territorial units (ATUs), correlated with the data from the interviews with local leaders, highlighted the types of local narratives regarding the capitalization of cultural resources and the openness to culture-centered community-based development, namely glocal, dynamic local and static local visions. The unitary and integrated approach of tourist resources, tourism social entrepreneurship, support from the local commons and a better management of the local cultural potential are ways to capitalize on belonging to the Făgăraș Land cultural landscape, towards sustainable community development of the area.
Determinants of Decision Making by Smallholder Farmers on Land Allocation for Small-Scale Forest Management in Northwestern Ethiopian Highlands
Authors: Mulu Solomon , Asfaw Zebene , Alemu Asmamaw , Teketay Demel
Published: June 2022

Smallholder farmers in the northwestern Ethiopian Highlands are highly engaged in small-scale forest management. Participation in this activity can provide a key source of income for the farmers as well as wider benefits to the environment. To gain a better understanding of how spatial and socio-ecological factors determine farmers’ engagements in small-scale forest management, we conducted a comparative study in three Districts of northwestern Ethiopia. We used a mixed method approach including both quantitative (n = 375) and qualitative (n = 45) surveys to understand farmers’ motivations and decisions in three Districts of northwestern Ethiopia. We found that there were a number of factors motivating farmers’ decisions to participate, including land degradation and decline in crop productivity (in Fagta Lekoma District); adverse impact of adjacent woodlots (in North Mecha District); and increasing demand of wood products (in Guna Begemidir District). Further analysis on the extent of farmer engagement revealed that their decision to increase or decrease the share of land allocated to woodlots is heavily dependent on the comparative socio-economic benefits of woodlots and distance to markets. Other key (District-specific) determinant factors included wealth status, soil fertility status, gender, adult equivalent value, total land holding size, and annual crop production risk perception. Our findings suggest that to increase the uptake of woodlots, we would need to adopt a demand-driven forestry extension approach, which considers the heterogeneity of farmers and farm characteristics. Further research is required to quantify the optimal level of land allocation for small-scale forest management.
6,10-Dichloro-1-oxa-4,8-dithia-7,9-diazaspiro[4.5]deca-6,9-diene
Authors: Kalogirou Andreas S. , Koutentis Panayiotis A.
Published: June 2022

Reaction of 3,4,4,5-tetrachloro-4H-1,2,6-thiadiazine with 2-mercaptoethan-1-ol (1 equiv.) gave 6,10-dichloro-1-oxa-4,8-dithia-7,9-diazaspiro[4.5]deca-6,9-diene in 12% yield. The compound was fully characterized.
Numerical Simulation Study of Expanding Fracture of 45 Steel Cylindrical Shell under Different Detonation Pressure
Authors: Huang Zhenwei , Yu Xinlu
Published: June 2022

Detonation and fragmentation of ductile cylindrical metal shells is a complicated physical phenomenon of material and structural fracture under a high strain rate and high-speed impact. In this article, the smoothed particle hydrodynamics (SPH) numerical model is adopted to study this problem. The model’s reliability is initially tested by comparing the simulation findings with experimental data, and it shows that different fracture modes of cylindrical shells can be obtained by using the same model with a unified constitutive model and failure parameters. By using this model to analyze the explosive fracture process of the cylindrical shells at various detonation pressures, it shows that when the detonation pressure decreases, the cylindrical metal shell fracture changes from a pure shear to tensile–shear mixed fracture. When the detonation pressure is above 31 GPA, a pure shear fracture appears in the shell during the loading stage of shell expansion, and the crack has an angle of 45° or 135° from the radial direction. When the pressure is reduced to 23 GPA, the fracture mode changes to tension–shear mixing, and the proportion of tensile cracks is about one-sixth of the shell fracture. With the explosion pressure reduced to 13 GPA, the proportion of tensile cracks is increased to about one-half of the shell fracture. Finally, the failure mechanism of the different fracture modes was analyzed under different detonation pressures by studying the stress and strain curves in the shells.
Remarkable Structural Modifications of Tialite Solid Solutions Obtained by Different Methods
Authors: Kornaus Kamil , Czekaj Izabela , Sobuś Natalia , Lach Radosław , Gubernat Agnieszka
Published: June 2022

The structural changes occurring in tialite due to the formation of magnesium-titanate–aluminum-titanate solid solutions were determined. For this purpose, a DFT simulation of the structural changes was performed. The simulation proposed a number of possible atomic substitutions occurring in the elementary cells of the tialite, along with calculations of the lattice parameter changes in this material. Next, the actual changes occurring in the structure of the tialite due to the formation of solid solutions, obtained in different ways, were investigated. After comparing the obtained results, it was possible to confirm the mechanism of the formation of tialite solid solutions, through which one magnesium atom and one titanium atom substituted two aluminum atoms simultaneously. The results of this experimental work were confirmed by theoretical calculations (the differences in the values of the lattice parameters, measured in the experiment and calculated in the simulation, were less than 0.5%), through which changes in the lattice parameters with Mg and Ti substitution were observed.
Mechanically Robust Dual-Crosslinking Elastomer Enabled by a Facile Self-Crosslinking Approach
Authors: Huang Zhendong , Jin Biqiang , Wu Haitao , Zeng Zihang , Huang Minghui , Wu Jinrong , Liao Lusheng , Zheng Jing
Published: June 2022

We propose a simple but rapid strategy to fabricate self-crosslinked dual-crosslinking elastomers (SCDCEs) with high mechanical properties. The SCDCEs are synthesized through one-pot copolymerization of Butyl acrylate (BA), acrylic amide (AM), and 3-Methacryloxypropyltrimethoxysilane (MEMO). Both the amino group on AM and the methoxy group on MEMO can be self-crosslinked after polymerization to form a dual-network crosslink consisting of hydrogen bonds crosslink and Si-O-Si covalent bonds crosslink. The SCDC endow optimal elastomer with high mechanical properties (the tensile strength is 6MPa and elongation at break is 490%) as the hydrogen bonds crosslink can serve as sacrificial construction to dissipate stress energy, while covalent crosslinking networks can ensure the elasticity and strength of the material. These two networks also contribute to the recoverability of the elastomers, leading them to recover their original shape and mechanical properties after being subjected to deformation in a short time.
Stress-Controlled Creep–Fatigue of an Advanced Austenitic Stainless Steel at Elevated Temperatures
Authors: Alsmadi Zeinab Y. , Abouelella Hamdy , Alomari Abdullah S. , Murty K. L.
Published: June 2022

Creep–fatigue interaction occurs in many structural components of high-temperature systems operating under cyclic and steady-state service conditions, such as in nuclear power plants, aerospace, naval, and other industrial applications. Thus, understanding micromechanisms governing high-temperature creep–fatigue behavior is essential for safety and design considerations. In this work, stress-controlled creep–fatigue tests of advanced austenitic stainless steel (Alloy 709) were performed at a 400 MPa stress range and 750 °C with tensile hold times of 0, 60, 600, 1800, and 3600 s, followed by microstructural examinations. The creep–fatigue lifetime of the Alloy 709 was found to decrease with increasing hold time until reaching a saturation level where the number of cycles to failure did not exhibit a significant decrease. Softening behavior was observed at the beginning of the test, possibly due to the recovery of entangled dislocations and de-twining. In addition, hysteresis loops showed ratcheting behavior, although the mean stress was zero during creep–fatigue cycling, which was attributed to activity of partial dislocations. Microstructural examination of the fracture surfaces showed that fatigue failure dominated at small hold times where the cracks initiated at the surface of the sample. Larger creep cracks were found for longer hold times with a lower probability of dimpled cavities, indicating the dominance of creep deformation. The results were compared with other commonly used stainless steels, and plausible reasons for the observed responses were described.
Effect of Rolling Treatment on Microstructure, Mechanical Properties, and Corrosion Properties of WE43 Alloy
Authors: Deng Bo , Dai Yilong , Lin Jianguo , Zhang Dechuang
Published: June 2022

Magnesium alloys show broad application prospects as biodegradable implanting materials due to their good biocompatibility, mechanical compatibility, and degradability. However, the influence mechanism of microstructure evolution during forming on the mechanical properties and corrosion resistance of the magnesium alloy process is not clear. Here, the effects of rolling deformation, such as cold rolling, warm rolling, and hot rolling, on the microstructure, mechanical properties, and corrosion resistance of the WE43 magnesium alloy were systematically studied. After rolling treatment, the grains of the alloy were significantly refined. Moreover, the crystal plane texture strength and basal plane density decreased first and then increased with the increase in rolling temperature. Compared with the as-cast alloy, the strength of the alloy after rolling was significantly improved. Among them, the warm-rolled alloy exhibited the best mechanical properties, with a tensile strength of 346.7 MPa and an elongation of 8.9%. The electrochemical experiments and immersion test showed that the hot working process can greatly improve the corrosion resistance of the WE43 alloy. The hot-rolled alloy had the best corrosion resistance, and its corrosion resistance rate was 0.1556 ± 0.18 mm/year.
Raman Spectroscopy of Janus MoSSe Monolayer Polymorph Modifications Using Density Functional Theory
Authors: Oreshonkov Aleksandr S. , Sukhanova Ekaterina V. , Popov Zakhar I.
Published: June 2022

Two-dimensional transition metal dichalcogenides (TMDs) with Janus structures are attracting increasing attention due to their emerging superior properties in breaking vertical mirror symmetry when compared to conventional TMDs, which can be beneficial in fields such as piezoelectricity and photocatalysis. The structural investigations of such materials, along with other 2D materials, can be successfully carried out using the Raman spectroscopy method. One of the key elements in such research is the theoretical spectrum, which may assist in the interpretation of experimental data. In this work, the simulated Raman spectrum of 1H-MoSSe and the predicted Raman spectra for 1T, 1T’, and 1H’ polymorph modifications of MoSSe monolayers were characterized in detail with DFT calculations. The interpretation of spectral profiles was made based on the analysis of the lattice dynamics and partial phonon density of states. The presented theoretical data open the possibility of an accurate study of MoSSe polymorphs, including the control of the synthesized material quality and the characterization of samples containing a mixture of polymorphs.
Retardation Effects of Filter Mud in Molasses on Composite Silicate Cement
Authors: He Xun , Jiang Hui , Wan Xin , Chen Kequan , Ouyang Pingkai
Published: June 2022

The filter mud in molasses has a significant inhibitory effect on biological activity and cannot be utilised by organisms; therefore, before molasses are biotransformed, the filter mud will be separated and directly discarded in the environment. In this study, the filter mud was used as the retarder of cement concrete OPC 42.5 for the first time. It was found that when 0.2–0.8% filter mud was added to fresh cement concrete OPC PC 42.5, the hardening time of cement slurry was significantly prolonged due to the synergistic retarding effect of sugar, colloid and total cellulose in the filter mud. In addition, the compressive strength of cement concrete mixed with the filter mud in the early stage (<10 days), middle stage (10–100 days) and later stage (180 days) was significantly higher than that of cement concrete and cement concrete mixed with commercial asphalt lignosulfonate. These results showed that the filter mud in molasses could realise harmless and resource utilisation, which could promote the comprehensive utilisation of molasses.
Impact of Polyrhodanine Manganese Ferrite Binary Nanohybrids (PRHD@MnFe2O4) on Osteoblasts and Osteoclasts Activities—A Key Factor in Osteoporosis Treatment
Authors: Marycz Krzysztof , Kowalczuk Anna , Turlej Eliza , Zachanowicz Emilia , Tomaszewska Anna , Kulpa-Greszta Magdalena , Kępska Martyna , Steczkiewicz Zofia , Pązik Robert
Published: June 2022

Osteoporosis is characterized by the reduction of bone mineral density and the weakness of the bone strength leading to fractures. Searching for new compounds that stimulate bone activity and their ability to reconstruct seems to be a promising tool in osteoporosis treatment. Here, we performed analyses comparing the impact of polyrhodanine (PRHD) and its derivatives on the viability (anti-proliferative tests), morphology and mitochondrial network (confocal microscopy) towards pre-osteoblasts (MC3T3-E1 cell line) and osteoclasts (4B12 cell line). Moreover, we assessed the expression of genes associated with the apoptosis, inflammation and osteogenic differentiation by qPCR technique. Our results clearly demonstrated that PRHD and its modification at ratio 10/90 significantly improves the pre-osteoblast’s proliferative abilities, while reducing osteoclast function. The observed effects were strongly correlated with the cytoskeleton and mitochondrial network development and arrangement. Additionally, the expression profile of genes revealed enhanced apoptosis of osteoclasts in the case of PRHD and its modification at ratio 10/90. Moreover, in this case we also observed strong anti-inflammatory properties demonstrated by decreased expression of Il1b, Tnfa and Tgfb in pre-osteoblasts and osteoclasts. On the other hand, enhanced expression of the markers associated with bone remodeling, namely, osteopontin (OPN), osteocalcin (OCL) and alkaline phosphatase (ALP), seem to confirm the role of PRHD@MnFe2O4 in the promotion of differentiation of pre-osteoblasts through the ALP-OPN-OCL axis. Based on these observations, PRHD@MnFe2O4 could be a potential agent in osteoporosis treatment in future, however, further studies are still required.
Influence of Surface Roughness on Biodegradability and Cytocompatibility of High-Purity Magnesium
Authors: Chen Jiahao , Dai Jingtao , Qian Junyu , Li Weirong , Li Ronghui , Pang Dong , Wan Guojiang , Li Ping , Xu Shulan
Published: June 2022

High-purity magnesium (Mg) is a promising biodegradable metal for oral and maxillofacial implants. Appropriate surface roughness plays a critical role in the degradation behavior and the related cellular processes of biodegradable Mg-based metals. Nevertheless, the most optimized surface roughness has been questionable, especially for Mg-based oral and maxillofacial implants. Three representative scales of surface roughness were investigated in this study, including smooth (Sa < 0.5 µm), moderately rough (Sa between 1.0–2.0 µm), and rough (Sa > 2.0 µm). The results indicated that the degradation rate of the Mg specimen in the cell culture medium was significantly accelerated with increased surface roughness. Furthermore, an extract test revealed that Mg with different roughness did not induce an evident cytotoxic effect. Nonetheless, the smooth Mg surface had an adversely affected cell attachment. Therefore, the high-purity Mg with a moderately rough surface exhibited the most optimized balance between biodegradability and overall cytocompatibility.
Atomic Interactions and Order–Disorder Transition in FCC-Type FeCoNiAl1−xTix High-Entropy Alloys
Authors: Wu Ying , Li Zhou , Feng Hui , He Shuang
Published: June 2022

Single-phase high-entropy alloys with compositionally disordered elemental arrangements have excellent strength, but show a serious embrittlement effect with increasing strength. Precipitation-hardened high-entropy alloys, such as those strengthened by L12-type ordered intermetallics, possess a superior synergy of strength and ductility. In this work, we employ first-principles calculations and thermodynamic simulations to explore the atomic interactions and order–disorder transitions in FeCoNiAl1−xTix high-entropy alloys. Our calculated results indicate that the atomic interactions depend on the atomic size of the alloy components. The thermodynamic stability behaviors of L12 binary intermetallics are quite diverse, while their atomic arrangements are short-range in FeCoNiAl1−xTix high-entropy alloys. Moreover, the order–disorder transition temperatures decrease with increasing Ti content in FeCoNiAl1−xTix high-entropy alloys, the characteristics of order–disorder transition from first-principles calculations are in line with experimental observations and CALPHAD simulations. The results of this work provide a technique strategy for proper control of the order–disorder transitions that can be used for further optimizing the microstructure characteristics as well as the mechanical properties of FeCoNiAl1−xTixhigh-entropy alloys.
Investigation on the Basic Characteristics of Semi-Fixed Abrasive Grains Polishing Technique for Polishing Sapphire (α-Al2O3)
Authors: Lei Yang , Feng Ming , Wu Ke , Chen Jinxi , Ji Jianghao , Yuan Julong
Published: June 2022

Single-crystal sapphire (α-Al2O3) is an important material and widely used in many advanced fields. The semi-fixed abrasive grain processing method based on solid-phase reaction theory is a prominent processing method for achieving ultra-precision damage-free surfaces. In order to develop the proposed method for polishing sapphire, the basic characteristics of the semi-fixed abrasive grains polishing tool for polishing sapphire were determined. Weight analysis was used to study the influence rules of parameters on surface roughness and material removal rates using an orthogonal experiment. Then, the optimized polishing tool was obtained through a mixture of abrasive particle sizes to reduce the difficulty in molding the polishing tool. Finally, polishing experiments using different polishing tools were carried out to investigate polishing performance by considering the surface roughness, material removal rate and the surface morphology during polishing. The results showed that (1) external load affects the surface roughness and material removal rate the most, followed by abrasive particle size, sand bond ratio, revolution speed of the workpiece and he polishing tool; (2) the difficulty in manufacturing the polishing tool could be reduced by mixing larger abrasive particles with small abrasive particles; (3) the polishing tool with 200 nm and 1 μm particle sizes performed best in the first 210 min polishing.
Natural Volcanic Material as a Sustainable Photocatalytic Material for Pollutant Degradation under Solar Irradiation
Authors: Borges María Emma , Navarro Silvia , de Paz Carmona Héctor , Esparza Pedro
Published: June 2022

Recently, photocatalysis has been demonstrated as a solid approach for efficient wastewater cleaning. Using natural materials as photocatalysts means a promising solution to develop green catalysts for environmental purposes. This work aimed to study the suitability of a natural volcanic material (La Gomera, Canary Islands, Spain) as a photocatalytic material for the degradation of pollutants in wastewater with solar energy. After analysing the properties of the natural material (BET surface 0.188 m2/g and band-gap of 3 eV), the photocatalytic activity was evaluated at laboratory and pilot plant scale for the degradation of methylene blue (MB) in water (50 mg L−1), at 20 °C, during a period of 4 h, under UV/Vis light and solar irradiation. Photolytic and adsorption studies were developed to distinguish the photocatalytic contribution to the wastewater decontamination process by photocatalysis. Our results enable us to determine the viability of black sand as a photocatalytic material activated by solar irradiation (photodegradation of MB up to 100% by using solar energy), developing a natural and green photocatalytic system with significantly high potential for application in a sustainable wastewater cleaning process.
Hypergraph and Uncertain Hypergraph Representation Learning Theory and Methods
Authors: Zhang Liyan , Guo Jingfeng , Wang Jiazheng , Wang Jing , Li Shanshan , Zhang Chunying
Published: June 2022

With the advent of big data and the information age, the data magnitude of various complex networks is growing rapidly. Many real-life situations cannot be portrayed by ordinary networks, while hypergraphs have the ability to describe and characterize higher order relationships, which have attracted extensive attention from academia and industry in recent years. Firstly, this paper described the development process, the application areas, and the existing review research of hypergraphs; secondly, introduced the theory of hypergraphs briefly; then, compared the learning methods of ordinary graphs and hypergraphs from three aspects: matrix decomposition, random walk, and deep learning; next, introduced the structural optimization of hypergraphs from three perspectives: dynamic hypergraphs, hyperedge weight optimization, and multimodal hypergraph generation; after that, the applicability of three uncertain hypergraph models were analyzed based on three uncertainty theories: probability theory, fuzzy set, and rough set; finally, the future research directions of hypergraphs and uncertain hypergraphs were prospected.
Effect of the Impact Coefficient of Restitution on the Nonlinear Dynamics Phenomenon of Flat-Faced Follower Mechanism with Clearance
Authors: Yousuf Louay S.
Published: June 2022

The effect of impact coefficient of restitution on the nonlinear response of the follower is investigated at different follower guides’ clearances, different cam speeds and different followers’ offsets. The impact between the cam and the follower and between the follower and its guide is considered in the presence of coefficient of restitution and follower offset. The nonlinear dynamics phenomenon of the follower due to the impact coefficient of restitution is detected using the approach of largest Lyapunov exponent. Moreover, the chaotic phenomenon is detected using a phase-plane diagram. The numerical simulation of the nonlinear response of the follower is calculated using the SolidWorks program. The chaotic phenomenon in the cam follower system is increased with the increase of the impact coefficient of restitution value in which the potential energy of the follower has been decreased in the presence of follower offset. The chaotic motion of the follower response occurs due to the increase in cam speeds, follower’s offsets, follower guides’ clearances and impact coefficient of restitution.
Emergent Intelligence in Smart Ecosystems: Conflicts Resolution by Reaching Consensus in Resource Management
Authors: Rzevski George , Skobelev Petr , Zhilyaev Alexey
Published: June 2022

A new emergent intelligence approach to the design of smart ecosystems, based on the complexity science principles, is introduced and discussed. The smart ecosystem for resource management is defined as a system of autonomous decision-making multi-agent systems capable to allocate resources, plan orders for resources, and to optimize, coordinate, monitor, and control the execution of plans in real time. The emergent intelligence enables software agents to collectively resolve conflicts arising in resource management decisions by reaching a consensus through a process of detecting conflicts and negotiation for finding trade-offs. The key feature of the proposed approach is the ontological model of the enterprise and the method of collective decision-making by software agents that compete or cooperate with each other on the virtual market of the digital ecosystem. Emergent intelligent systems do not require extensive training using a large quantity of data, like conventional artificial intelligence/machine learning systems. The developed model, method, and tool were applied for managing the resources of a factory workshop, a group of small satellites, and some other applications. A comparison of the developed and traditional tools is given. The new metric for measuring the adaptability of emergent intelligence is introduced. The performance of the new model and method are validated by constructing and evaluating large-scale resource management solutions for commercial clients. As demonstrated, the essential benefit is the high adaptability and efficiency of the resource management systems when operating under complex and dynamic market conditions.
KIAA1363—A Multifunctional Enzyme in Xenobiotic Detoxification and Lipid Ester Hydrolysis
Authors: Wagner Carina , Hois Victoria , Taschler Ulrike , Schupp Michael , Lass Achim
Published: June 2022

KIAA1363, annotated as neutral cholesterol ester hydrolase 1 (NCEH1), is a member of the arylacetamide deacetylase (AADAC) protein family. The name-giving enzyme, AADAC, is known to hydrolyze amide and ester bonds of a number of xenobiotic substances, as well as clinical drugs and of endogenous lipid substrates such as diglycerides, respectively. Similarly, KIAA1363, annotated as the first AADAC-like protein, exhibits enzymatic activities for a diverse substrate range including the xenobiotic insecticide chlorpyrifos oxon and endogenous substrates, acetyl monoalkylglycerol ether, cholesterol ester, and retinyl ester. Two independent knockout mouse models have been generated and characterized. However, apart from reduced acetyl monoalkylglycerol ether and cholesterol ester hydrolase activity in specific tissues and cell types, no gross-phenotype has been reported. This raises the question of its physiological role and whether it functions as drug detoxifying enzyme and/or as hydrolase/lipase of endogenous substrates. This review delineates the current knowledge about the structure, function and of the physiological role of KIAA1363, as evident from the phenotypical changes inflicted by pharmacological inhibition or by silencing as well as knockout of KIAA1363 gene expression in cells, as well as mouse models, respectively.
Untargeted Metabolomics Profiling Reveals Perturbations in Arginine-NO Metabolism in Middle Eastern Patients with Coronary Heart Disease
Authors: Ullah Ehsan , El-Menyar Ayman , Kunji Khalid , Elsousy Reem , Mokhtar Haira R. B. , Ahmad Eiman , Al-Nesf Maryam , Beotra Alka , Al-Maadheed Mohammed , Mohamed-Ali Vidya , Saad Mohamad , Al Suwaidi Jassim
Published: June 2022

Coronary heart disease (CHD) is a major cause of death in Middle Eastern (ME) populations, with current studies of the metabolic fingerprints of CHD lacking in diversity. Identification of specific biomarkers to uncover potential mechanisms for developing predictive models and targeted therapies for CHD is urgently needed for the least-studied ME populations. A case-control study was carried out in a cohort of 1001 CHD patients and 2999 controls. Untargeted metabolomics was used, generating 1159 metabolites. Univariate and pathway enrichment analyses were performed to understand functional changes in CHD. A metabolite risk score (MRS) was developed to assess the predictive performance of CHD using multivariate analysis and machine learning. A total of 511 metabolites were significantly different between the CHD patients and the controls (FDR p < 0.05). The enriched pathways (FDR p < 10−300) included D-arginine and D-ornithine metabolism, glycolysis, oxidation and degradation of branched chain fatty acids, and sphingolipid metabolism. MRS showed good discriminative power between the CHD cases and the controls (AUC = 0.99). In this first study in the Middle East, known and novel circulating metabolites and metabolic pathways associated with CHD were identified. A small panel of metabolites can efficiently discriminate CHD cases and controls and therefore can be used as a diagnostic/predictive tool.
Mechanism and Kinetics of Stibnite Dissolution in H2SO4-NaCl-Fe(SO4)1.5-O2
Authors: Padilla Rafael , Caro Oscar , Vega-Garcia Dennis , Ruiz María C.
Published: June 2022

This paper is concerned with the kinetics of stibnite (Sb2S3) dissolution in H2SO4-NaCl-Fe(SO4)1.5-O2 solutions. The experimental results of our study showed a positive effect from ferric ions on stibnite dissolution of up to 0.05 M. An increase in H2SO4 concentration from 0.8 to 3 M and NaCl concentration from 0 to 3 M NaCl improved the stibnite dissolution. In solutions without ferric ions, the leaching occurs by the acid dissolution reaction producing H2S without forming elemental sulfur, as we confirmed by the X-ray diffraction (XRD) analysis of leach residues. In this case, the kinetic data was analyzed using a shrinking core model controlled by a chemical reaction, and the calculated activation energy was 54.6 kJ/mol. Conversely, in the presence of ferric ions, the XRD patterns of the leach residues showed large peaks for elemental sulfur, confirming that the stibnite was oxidized and formed a sulfur porous layer. The mechanism in the presence of ferric ions involved an acid dissolution reaction, with the diffusion of the reactant/product species through the porous product layer, followed by the oxidation of H2S by ferric ions. The kinetic data were analyzed using a diffusion-controlled model, and the activation energy was 123.8 kJ/mol. This high activation value is consistent with the proposed mechanism.
The Use of Antibiotics as Chiral Selectors in Capillary Electrophoresis: A Review
Authors: Hancu Gabriel , Papp Lajos Attila , Szekely-Szentmiklosi Blanka , Kelemen Hajnal
Published: June 2022

Chirality is becoming an essential issue in modern pharmaceutical research as regulatory agencies emphasize the safety and efficiency of enantiomers in drug development. The development of efficient and reliable chiral separation methods became a necessity in the last 30 years, and capillary electrophoresis (CE), due to its relatively low costs and “green” features, is attracting increased attention. Cyclodextrin (CD) and their derivatives are the most frequently used chiral selectors (CSs) in CE, however, the use of antibiotics as CSs represents an interesting alternative. Various classes of antibiotics (aminoglycosides, ansamycins, glycopeptides, lincosamides, macrolides, tetracyclines) have been used more or less successfully for the enantio-separation of pharmaceuticals. Antibiotics offer the possibility of a multitude of potential interactions (electrostatic, inclusion, hydrogen bonding, etc.) due to their chemical diversity, allowing the enantio-separation of analytes with a wide range of structural characteristics. This article aims to review the application of various classes of antibiotics in the CE enantio-separation of pharmaceuticals. Antibiotic physiochemical characteristics, variables impacting enantio-separation, advantages, and disadvantages when certain antibiotics are used as CSs in CE are also explored.
Effect of Cyclodextrins on the Biofilm Formation Capacity of Pseudomonas aeruginosa PAO1
Authors: Berkl Zsófia , Fekete-Kertész Ildikó , Buda Kata , Vaszita Emese , Fenyvesi Éva , Szente Lajos , Molnár Mónika
Published: June 2022

Quorum sensing (QS) is a population-density-dependent communication process of microorganisms to coordinate their activities by producing and detecting low-molecular-weight signal molecules. In pathogenic bacteria, the property controlled by QS is often related to infectivity, e.g., biofilm formation. Molecular encapsulation of the QS signals is an innovative method to prevent the signals binding to the receptors and to attenuate QS. Cyclodextrins (CDs) may form an inclusion complex with the signals, thus reducing the communication (quorum quenching, QQ). A systematic study was performed with α-, β-cyclodextrin, and their random methylated, quaternary amino and polymer derivatives to evaluate and compare their effects on the biofilm formation of Pseudomonas aeruginosa. To examine the concentration-, temperature- and time-dependency of the QQ effect, the CDs were applied at a 0.1–12.5 mM concentration range, and biofilm formation was studied after 6, 24, 48 and 72 h at 22 and 30 °C. According to the results, the QS mechanism was significantly inhibited; the size of the cavity, the structure of the substituents, as well as the monomeric or polymeric character together with the concentration of the CDs have been identified as key influencing factors of biofilm formation. Statistically determined effective concentration values demonstrated outstanding efficiency (higher than 80% inhibition) of α-CD and its random methylated and polymer derivatives both on the short and long term. In summary, the potential value of CDs as inhibitors of QS should be considered since the inhibition of biofilm formation could significantly impact human health and the environment.
Isoquinoline Alkaloid Contents in Macleaya cordata Extracts and Their Acetylcholinesterase and Butyrylcholinesterase Inhibition
Authors: Tuzimski Tomasz , Petruczynik Anna , Szultka-Młyńska Małgorzata , Sugajski Mateusz , Buszewski Bogusław
Published: June 2022

An important strategy for treating neurodegenerative disorders is to maintain the levels of acetylcholine in the synaptic cleft by blocking the cholinesterases. Searching for new effective compounds with inhibited acetylcholinesterase and butyrylcholinesterase activity is one of the most significant challenges of the modern scientific research. The aim of this study was the optimization of the condition for cholinesterase activity determination by high-performance liquid chromatography coupled with diode array detector (HPLC-DAD) in terms of concentrations of enzymatic reaction mixture components, temperature of incubation, and incubation time. In vitro investigation of acetylcholinesterase and butyrylcholinesterase activity inhibition by some isoquinoline alkaloids and extracts obtained from the aerial part and roots of Macleaya cordata collected in May, July, and September. Acetylcholinesterase and butyrylcholinesterase activity inhibition of the extracts obtained from the plant had not been tested previously. The application of the HPLC method allowed eliminating absorption of interfering components, for example, alkaloids such as sanguinarine and berberine. The HPLC method was successfully applied for the evaluation of the acetylcholinesterase inhibitory activity in samples such as plant extracts, especially those containing colored components adsorbing at the same wavelength as the adsorption wavelength of 5-thio-2-nitro-benzoic acid, which is the product of the reaction between thiocholine (product of the hydrolysis of acetyl/butyrylthiocholine reaction) with Ellman’s reagent. Moreover, liquid chromatography coupled with a triple quadrupole mass spectrometer (LC–QqQ–ESI–MS/MS) analysis allowed evaluating the identification of relevant bioactive compounds in the obtained plant extracts. The investigated alkaloids, especially sanguinarine and chelerythrine, and all the Macleaya cordata extracts, especially the extract obtained from the aerial part collected in May, exhibited very high cholinesterase activity inhibition. HPLC-DAD was also applied for the kinetics study of the most active alkaloids sanguinarine and chelerythrine. Our investigations demonstrated that these plant extracts can be recommended for further in vivo experiments to confirm their cholinesterase inhibition activity.
A Ten-Minute Synthesis of α-Ni(OH)2 Nanoflakes Assisted by Microwave on Flexible Stainless-Steel for Energy Storage Devices
Authors: Alshareef Sumaih F. , Alhebshi Nuha A. , Almashhori Karima , Alshaikheid Haneen S. , Al-hazmi Faten
Published: June 2022

Although numerous methods have been widely used to prepare nickel hydroxide materials, there is still a demand for lowering the required heating time, temperature, and cost with maintaining a high-quality nanomaterial for electrochemical energy storage. In this research, we study the relationship between microwave-assisted heating parameters and material properties of nickel hydroxide nanoflakes and evaluate their effect on electrochemical performance. X-ray diffraction spectra show that the samples prepared at the highest temperature of 220 °C have crystallized in the beta phase of nickel hydroxide crystal. While the sample synthesized at 150 °C in 30 min contains both beta and alpha phases. Interestingly, we obtained the pure alpha phase at 150 °C in just 10 min. A scanning electron microscope shows that increasing the temperature and heating time leads to enlarging the diameter of the macro-porous flower-like clusters of interconnected nanoflakes. Electrochemical measurements in potassium hydroxide electrolytes demonstrate that the alpha phase’s electrodes have much higher capacities than samples containing only the beta phase. The maximum areal capacity of 17.7 µAh/cm2 and gravimetric capacity of 35.4 mAh/g are achieved, respectively, at 0.2 mA/cm2 and 0.4 A/g, with a small equivalent series resistance value of 0.887 ohms on flexible stainless-steel mesh as a current collector. These improved nickel hydroxide electrodes can be ascribed to utilizing the diffusion-controlled redox reactions that are detected up to the high scan of 100 mV/s. Such fast charge-discharge processes expand the range of potential applications. Our nickel hydroxide electrode, with its rapid preparation at medium temperature, can be a cost-effective candidate for flexible supercapacitors and batteries.
Recent Advances of Nanomaterials-Based Molecularly Imprinted Electrochemical Sensors
Authors: Dong Xinning , Zhang Congcong , Du Xin , Zhang Zhenguo
Published: June 2022

Molecularly imprinted polymer (MIP) is illustrated as an analogue of a natural biological antibody-antigen system. MIP is an appropriate substrate for electrochemical sensors owing to its binding sites, which match the functional groups and spatial structure of the target analytes. However, the irregular shapes and slow electron transfer rate of MIP limit the sensitivity and conductivity of electrochemical sensors. Nanomaterials, famous for their prominent electron transfer capacity and specific surface area, are increasingly employed in modifications of MIP sensors. Staying ahead of traditional electrochemical sensors, nanomaterials-based MIP sensors represent excellent sensing and recognition capability. This review intends to illustrate their advances over the past five years. Current limitations and development prospects are also discussed.
Role of Tree Species, the Herb Layer and Watershed Characteristics in Nitrate Assimilation in a Central Appalachian Hardwood Forest
Authors: Eisenhut Sian E. , Holásková Ida , Stephan Kirsten
Published: June 2022

Forest plants that can assimilate nitrate may act as nitrate sink and, consequently, reduce nitrate losses from watershed ecosystems through leaching. This study, conducted at the Fernow Experimental Forest in West Virginia, quantified via nitrogen reductase activity (NRA) the nitrate assimilation of two tree species, red maple and sugar maple, and surrounding common herb-layer species at the tissue (foliage, roots) and plot level. NRA measurements were conducted in summer and spring. Furthermore, NRA was quantified under varying levels of soil nitrate availability due to fertilization, different stages in secondary forest succession, and watershed aspect. This study confirmed that NRA of mature maples does not respond to varying levels of soil nitrate availability. However, some herb-layer species’ NRA did increase with nitrogen fertilization, and it may be greater in spring than in summer. Combined with biomass, the herb layer’s NRA at the plot-level (NRAA) comprised 9 to 41% of the total (tree + herb-layer) foliar NRAA during the growing season. This demonstrates that the herb layer contributes to nitrate assimilation disproportionally to its small biomass in the forest and may provide a vernal dam to nitrate loss not only by its early presence but also by increased spring NRA relative to summer.
Thawing Permafrost as a Nitrogen Fertiliser: Implications for Climate Feedbacks
Authors: Burke Eleanor , Chadburn Sarah , Huntingford Chris
Published: June 2022

Studies for the northern high latitudes suggest that, in the near term, increased vegetation uptake may offset permafrost carbon losses, but over longer time periods, permafrost carbon decomposition causes a net loss of carbon. Here, we assess the impact of a coupled carbon and nitrogen cycle on the simulations of these carbon fluxes. We present results from JULES-IMOGEN—a global land surface model coupled to an intermediate complexity climate model with vertically resolved soil biogeochemistry. We quantify the impact of nitrogen fertilisation from thawing permafrost on the carbon cycle and compare it with the loss of permafrost carbon. Projections show that the additional fertilisation reduces the high latitude vegetation nitrogen limitation and causes an overall increase in vegetation carbon uptake. This is a few Petagrams of carbon (Pg C) by year 2100, increasing to up to 40 Pg C by year 2300 for the RCP8.5 concentration scenario and adds around 50% to the projected overall increase in vegetation carbon in that region. This nitrogen fertilisation results in a negative (stabilising) feedback on the global mean temperature, which could be equivalent in magnitude to the positive (destabilising) temperature feedback from the loss of permafrost carbon. This balance depends on the future scenario and initial permafrost carbon. JULES-IMOGEN describes one representation of the changes in Arctic carbon and nitrogen cycling in response to climate change. However there are uncertainties in the modelling framework, model parameterisation and missing processes which, when assessed, will provide a more complete picture of the balance between stabilising and destabilising feedbacks.