bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial-Temporal Dynamic Evaluation of Ecosystem Service Value and Its Driving Mechanisms in China
Authors: Wei Xiaojian , Zhao Li , Cheng Penggen , Xie Mingrui , Wang Huimin
Published: July 2022

Understanding the spatial differentiation and driving mechanisms of ecosystem service value (ESV) is helpful for the protection and sustainable development of the ecological environment. Despite the fact that various studies on ESV have been conducted in various regions, few studies have discussed the spatial differentiation characteristics of ESV in a long time series at a national scale, and even fewer studies have thoroughly examined the driving mechanism of the spatial differentiation of ESV from the perspective of different regions. On the basis of China’s land use data from 1990 to 2018, this paper used the methods of land use dynamics, the ESV evaluation model, hot spot analysis, the barycenter model, and the geographical detector model to study the temporal and spatial differentiation characteristics of land use and ESV in the study area. Moreover, it analyzes the driving mechanisms of the spatial differentiation of ESV at the national scale and in different regions of China. Our results showed the following: (1) Other land types have increased overall, with the exception of grassland. Obvious differences were observed in the single land use dynamics of each land type, especially the construction land, where farmland was the primary source of construction land. With the passage of time, the dynamic degree of comprehensive land use increased. (2) During the study period, ESV generally showed a decreasing trend, with distinct characteristics in high and low ESV areas. The center of gravity of ESV was constantly in Dingxi County and Pingliang City, Shaanxi Province, and its trajectory was generally “S”-shaped. (3) From the perspective of national scale and different regions, the dominant factors affecting the spatial differentiation of ESV were different, and the interaction among multiple factors was significantly stronger than that of a single factor. The findings of the study can provide more scientific decision-making services for China in order to promote regional environmental protection and develop ecological civilization.
Thermal Annealing Effects of V2O5 Thin Film as an Ionic Storage Layer for Electrochromic Application
Authors: Lin Tien-Chai , Jheng Bai-Jhong , Yen Hui-Min , Huang Wen-Chang
Published: July 2022

A vanadium pentoxide (V2O5) thin film with thermal annealing as an ionic storage layer for electrochromic devices is presented in our study. The V2O5 thin film was deposited on an ITO glass substrate by an RF magnetron sputtering. The electrochromic properties of the film were evaluated after various thermal annealing temperatures. The structural analysis of the film was observed by X-ray diffraction (XRD), field emission electron microscopy (FE-SEM), and atomic force microscopy (AFM). The structure of the V2O5 thin film transformed from an amorphous to polycrystalline structure with directions of (110) and (020) after 400 °C thermal annealing. The electrochromic properties of the film improved compared with the unannealed V2O5 thin film. We obtained a charge capacity of 97.9 mC/cm2 with a transparent difference ΔT value of 31% and coloration efficiency of 6.3 cm2/C after 400 °C thermal annealing. The improvement was due to the polycrystalline orthorhombic structure formation of V2O5 film by the rearrangement of atoms from thermal energy. Its laminate structure facilitates Li+ ion intercalation and increases charge capacity and transparent difference.
Tuning Microstructure and Mechanical Performance of a Co-Rich Transformation-Induced Plasticity High Entropy Alloy
Authors: Yi Hailong , Xie Renyi , Zhang Yifan , Wang Liqiang , Tan Min , Li Tao , Wei Daixiu
Published: July 2022

Multi-principal element alloys and high-entropy alloys (HEAs) are emerging metallic materials with unprecedented structures and properties for various applications. In this study, we tuned the microstructure and mechanical performance of a recently designed high-performance Co-rich TRIP-HEA via thermomechanical processing (TMP). The microstructures of the HEA after various TMP routines were characterized, and their correlation with room-temperature tensile performance was clarified. The results showed that grain refinement is an effective strategy for enhancing strength while retaining satisfactory ductility. The formation of incoherent precipitates slightly improves the strength but inevitably sacrifices the ductility, which needs to be considered for optimizing the TMPs. The room temperature tensile yield strength and ultimate tensile strength were increased from 254.6 to 641.3 MPa and from 702.5 to 968.4 MPa, respectively, but the tensile elongation retains a satisfactory value of 68.8%. We herein provide important insights into the regulation of the microstructure and mechanical properties of TRIP-HEAs.
Carbon Transformation Induced by High Energy Excimer Treatment
Authors: Slepičková Kasálková Nikola , Hurtuková Klaudia , Fajstavr Dominik , Lapčák Ladislav , Sajdl Petr , Kolská Zdeňka , Švorčík Václav , Slepička Petr
Published: July 2022

The main aim of this study was to describe the treatment of carbon sheet with a high-energy excimer laser. The excimer modification changed the surface chemistry and morphology of carbon. The appearance of specific carbon forms and modifications have been detected due to exposure to laser beam fluencies up to 8 J cm−2. High fluence optics was used for dramatic changes in the carbon layer with the possibility of Q-carbon formation; a specific amorphous carbon phase was detected with Raman spectroscopy. The changes in morphology were determined with atomic force microscopy and confirmed with scanning electron microscopy, where the partial formation of the Q-carbon phase was detected. Energy dispersive spectroscopy (EDS) was applied for a detailed study of surface chemistry. The particular shift of functional groups induced on laser-treated areas was determined by X-ray photoelectron spectroscopy. For the first time, high-dose laser exposure successfully induced a specific amorphous carbon phase.
Enhanced Reactivity and Compound Mechanism of Mg/B Composite Powders Prepared by Cryomilling
Authors: Zhang Chi , Wang Qin , Tang Liying , Chen Fei
Published: July 2022

Boron is one of the highest energy density materials. The heat of boron is difficult to carry out due to its poor combustion performance. Magnesium (10 wt.%), acting as combustion adjuvant, is added into boron powder to improve the combustion performance. In this study, two kinds of boron powder were used as raw material, boron powder with an average size of 40 μm is named B1, and B2 has an average powder size of 3 μm. Mg/B composite powder was prepared though a cryomilling method. Two compound mechanisms for Mg/B composite powder were applied. For Mg/B1 composite powder, an Mg-coating structure on the surface of B was generated. For Mg/B2, a structure that small particles were agglomerated with Mg in the interior or on the surface of B was generated. Compared with either B powder or blended Mg/B powder, the reactivity of Mg/B composite powder by cryomilling is enhanced. In addition, the atomic ratio of Mg to B and activity content of Mg on the surface of Mg/B composite powder have great impacts on the improvement of reactivity.
The Heat Partition Ratio during Braking in a Functionally Graded Friction Couple
Authors: Yevtushenko Aleksander , Topczewska Katarzyna , Zamojski Przemysław
Published: July 2022

The theoretical scheme for determining the heat partition ratio (HPR) in a friction couple made of functionally graded materials (FGMs) was proposed. As a result, the formula for the calculation of the HPR was found, which depends on the thermal properties and the parameters of the material’s gradient. In specific cases of these parameters, the known formulas for estimating the HPR for homogeneous materials were obtained. Calculations were carried out for the friction couple consisting of the following two-component FGMs: Al2O3–Cu (first body) and ZrO2–Ti–6Al–4V (second body), under the conditions corresponding to a single braking with a constant deceleration. It was established that the vast majority (almost 90%) of heat that was generated by friction was absorbed by the first body in the selected couple. The possibilities of using the obtained results were discussed herein.
Cu-TCPP Nanosheets-Sensitized Electrode for Simultaneous Determination of Hydroquinone and Catechol
Authors: Ji Liudi , Wang Qi , Peng Lianhui , Li Xiaoyu , Zhu Xiaoming , Hu Peng
Published: July 2022

It is quite important to develop sensitive, simple, and convenient methods for the simultaneous determination of Hydroquinone (HQ) and Catechol (CC) due to their wide existence, the difficulty of degradation, and the high toxicity. Herein, Cu-TCPP nanosheets were prepared in N,N-dimethylformamide (DMF) through the solvent exfoliation method. The morphology and electrochemical performance of Cu-TCPP were characterized, revealing its stacked sheet structure with abundant pores, a fast electron transfer ability, and a large electrode active area. Using Cu-TCPP nanosheets as the sensitive material to modify the glassy carbon electrodes (Cu-TCPP/GCEs), it was found that they had an obvious enhancement effect on the electrochemical oxidation currents of HQ and CC. The signal enhancement mechanism was explored. The Cu-TCPP nanosheets not only enhanced the accumulation abilities of HQ and CC, but also improved their apparent catalytic rate, displaying high sensitivity for HQ and CC. The values of the detection limit were calculated to be 3.4 and 2.3 nM for HQ and CC. A satisfactory recovery was obtained when this method was used in measuring HQ and CC in the water samples.
A Note on Outer-Independent 2-Rainbow Domination in Graphs
Authors: Cabrera-Martínez Abel
Published: July 2022

Let G be a graph with vertex set V(G) and f:V(G)→{∅,{1},{2},{1,2}} be a function. We say that f is an outer-independent 2-rainbow dominating function on G if the following two conditions hold: (i)V∅={x∈V(G):f(x)=∅} is an independent set of G. (ii)∪u∈N(v)f(u)={1,2} for every vertex v∈V∅. The outer-independent 2-rainbow domination number of G, denoted by γr2oi(G), is the minimum weight ω(f)=∑x∈V(G)|f(x)| among all outer-independent 2-rainbow dominating functions f on G. In this note, we obtain new results on the previous domination parameter. Some of our results are tight bounds which improve the well-known bounds β(G)≤γr2oi(G)≤2β(G), where β(G) denotes the vertex cover number of G. Finally, we study the outer-independent 2-rainbow domination number of the join, lexicographic, and corona product graphs. In particular, we show that, for these three product graphs, the parameter achieves equality in the lower bound of the previous inequality chain.
Main Curvatures Identities on Lightlike Hypersurfaces of Statistical Manifolds and Their Characterizations
Authors: Bahadır Oğuzhan , Siddiqui Aliya Naaz , Gülbahar Mehmet , Alkhaldi Ali Hussain
Published: July 2022

In this study, some identities involving the Riemannian curvature invariants are presented on lightlike hypersurfaces of a statistical manifold in the Lorentzian settings. Several inequalities characterizing lightlike hypersurfaces are obtained. These inequalities are also investigated on lightlike hypersurfaces of Lorentzian statistical space forms.
OL-JCMSR: A Joint Coding Monitoring Strategy Recommendation Model Based on Operation Log
Authors: Sun Guoqiang , Xu Peng , Guo Man , Sun Hao , Du Zhaochen , Li Yujun , Zhou Bin
Published: July 2022

A surveillance system with more than hundreds of cameras and much fewer monitors strongly relies on manual scheduling and inspections from monitoring personnel. A monitoring method which improves the surveillance performance by analyzing and learning from a large amount of manual operation logs is proposed in this paper. Compared to fixed rules or existing computer-vision methods, the proposed method can more effectively learn from the operators’ behaviors and incorporate their intentions into the monitoring strategy. To the best of our knowledge, this method is the first to apply a monitoring-strategy recommendation model containing a global encoder and a local encoder in monitoring systems. The local encoder can adaptively select important items in the operating sequence to capture the main purpose of the operator, while the global encoder is used to summarize the behavior of the entire sequence. Two experiments are conducted on two data sets. Compared with att-RNN and att-GRU, the joint coding model in experiment 1 improves the Recall@20 by 9.4% and 4.6%, respectively, and improves the MRR@20 by 5.49% and 3.86%, respectively. In experiment 2, compared with att-RNN and att-GRU, the joint coding model improves by 11.8% and 6.2% on Recall@20, and improves by 7.02% and 5.16% on MRR@20, respectively. The results illustrate the effectiveness of the our model in monitoring systems.
A Reliable Way to Deal with Fractional-Order Equations That Describe the Unsteady Flow of a Polytropic Gas
Authors: Al-Sawalha M. Mossa , Agarwal Ravi P. , Shah Rasool , Ababneh Osama Y. , Weera Wajaree
Published: July 2022

In this paper, fractional-order system gas dynamics equations are solved analytically using an appealing novel method known as the Laplace residual power series technique, which is based on the coupling of the residual power series approach with the Laplace transform operator to develop analytical and approximate solutions in quick convergent series types by utilizing the idea of the limit with less effort and time than the residual power series method. The given model is tested and simulated to confirm the proposed technique’s simplicity, performance, and viability. The results show that the above-mentioned technique is simple, reliable, and appropriate for investigating nonlinear engineering and physical problems.
Towards Trustworthy Safety Assessment by Providing Expert and Tool-Based XMECA Techniques
Authors: Babeshko Ievgen , Illiashenko Oleg , Kharchenko Vyacheslav , Leontiev Kostiantyn
Published: July 2022

Safety assessment of modern critical instrumentation and control systems is a complicated process considerably dependent on expert techniques, single/multiple faults consideration scope, other assumptions, invoked limitations, and support tools used during the assessment process. Ignoring these assumptions, as well as the significance of expert and tool influence, could lead to such effects as functional safety underestimation or overestimation in such a manner that functional safety assessment correctness and accuracy are affected. This paper introduces XMECA (x modes, effects, and criticality analysis, where x could be from different known techniques and domains—failures in functional safety, vulnerabilities and intrusions regarding cybersecurity, etc.) as a key technique of safety assessment. To verify the results obtained as XMECA deliverables, expert and uncertainty modes, effects, and criticality analysis (EUMECA) is performed, in particular focusing on decisions and judgments made by experts. Scenarios for processing verbal and quantitative information of XMECA tables from experts are offered. A case study of a possible functional safety assessment approach that considers the above-mentioned techniques and a supporting tool is provided. To assess the trustworthiness of safety analysis and estimation using XMECA, a set of the metrics is suggested. Features of adapting the suggested method for security assessment considering intrusions, vulnerabilities, and effects analysis (IMECA technique) are discussed.
TyG Index Performs Better Than HOMA-IR in Chinese Type 2 Diabetes Mellitus with a BMI < 35 kg/m2: A Hyperglycemic Clamp Validated Study
Authors: Luo Ping , Cao Yaoquan , Li Pengzhou , Li Weizheng , Song Zhi , Fu Zhibing , Zhou Hui , Yi Xianhao , Zhu Liyong , Zhu Shaihong
Published: July 2022

Background and objectives: Chinese type 2 diabetes mellitus (T2DM) patients are characterized by a low body mass index (BMI), and significant insulin resistance (IR). The triglyceride glucose (TyG) index has not been studied as a means of assessing IR in Chinese T2DM patients with a BMI < 35 kg/m2. Materials and Methods: An open-label cross-sectional study recruited 102 Chinese T2DM patients with a BMI < 35 kg/m2. The hyper-insulinemic euglycemic clamp, homeostatic model assessment of IR (HOMA-IR), and TyG index were used to determine the level of IR. Based on Pearson’s correlations, glucose disposal rate (GDR), TyG index, and HOMA-IR were analyzed. HOMA-IR and TyG index for IR were evaluated using multiple linear regression and multivariate logistic regression analyses. On the basis of the receiver operating characteristic (ROC) curve, the sensitivity, specificity, and optimal cut-off value of HOMA-IR and the TyG index were determined. Results: The mean values of GDR, HOMA-IR, and TyG index were 4.25 ± 1.81, 8.05 ± 7.98, and 8.12 ± 0.86 mg/kg/min, respectively. Pearson’s correlation coefficient was −0.418 between GDR and TyG index and −0.324 between GDR and HOMA-IR. ROC curve analysis showed that, among both sexes, the TyG index was a better discriminator of IR than HOMA-IR. The area under the ROC curve (AUC) of the TyG index (0.785, 0.691–0.879) was higher than that of HOMA-IR (0.73, 0.588–0.873) in all genders. The optimal cut-off values of the TyG index and HOMA-IR were 7.99 and 3.39, respectively. Conclusions: The TyG index showed more effectiveness in identifying IR in Chinese T2DM patients with a BMI < 35 kg/m2 compared to HOMA-IR.
Statistical Simulation, a Tool for the Process Optimization of Oily Wastewater by Crossflow Ultrafiltration
Authors: Aloulou Hajer , Attia Afef , Aloulou Wala , Chakraborty Sudip , Baklouti Lassaad , Dammak Lasaad , Amar Raja Ben
Published: July 2022

This work aims to determine the optimized ultrafiltration conditions for industrial wastewater treatment loaded with oil and heavy metals generated from an electroplating industry for water reuse in the industrial process. A ceramic multitubular membrane was used for the almost total retention of oil and turbidity, and the high removal of heavy metals such as Pb, Zn, and Cu (>95%) was also applied. The interactive effects of the initial oil concentration (19–117 g/L), feed temperature (20–60 °C), and applied transmembrane pressure (2–5 bar) on the chemical oxygen demand removal (RCOD) and permeate flux (Jw) were investigated. A Box–Behnken experimental design (BBD) for response surface methodology (RSM) was used for the statistical analysis, modelling, and optimization of operating conditions. The analysis of variance (ANOVA) results showed that the COD removal and permeate flux were significant since they showed good correlation coefficients of 0.985 and 0.901, respectively. Mathematical modelling revealed that the best conditions were an initial oil concentration of 117 g/L and a feed temperature of 60 °C, under a transmembrane pressure of 3.5 bar. In addition, the effect of the concentration under the optimized conditions was studied. It was found that the maximum volume concentrating factor (VCF) value was equal to five and that the pollutant retention was independent of the VCF. The fouling mechanism was estimated by applying Hermia’s model. The results indicated that the membrane fouling given by the decline in the permeate flux over time could be described by the cake filtration model. Finally, the efficiency of the membrane regeneration was proved by determining the water permeability after the chemical cleaning process.
Assessment of Tissue Specific Distribution and Seasonal Variation of Alkaloids in Alstonia scholaris
Authors: Mahar Rohit , Manivel Nagarajan , Kanojiya Sanjeev , Mishra Dipak K. , Shukla Sanjeev K.
Published: July 2022

Alstonia scholaris is a well-known source of alkaloids and widely recognized for therapeutic purposes to treat the ailments in human and livestock. However, the composition and production of alkaloids vary due to tissue specific metabolism and seasonal variation. This study investigated alkaloids in leaves, stems, trunk barks, fruits, and flowers of A. scholaris. The impact of seasonal changes on the production of alkaloids in the leaves of A. scholaris was also investigated. One and two-dimensional Nuclear Magnetic Resonance (NMR) experiments were utilized for the characterization of alkaloids and total eight alkaloids (picrinine, picralinal, akuammidine, 19 S scholaricine, 19,20 E vallesamine, Nb-demethylalstogustine N-Oxide, Nb-demethylalstogustine, and echitamine) were characterized and quantified. Quantitative and multivariate analysis suggested that the alkaloids content is tissue specific, illustrating the effect of plant tissue organization on alkaloidal production in A. scholaris. The results suggest that the best part to obtain alkaloids is trunk barks, since it contains 7 alkaloids. However, the best part for isolating picrinine, picralinal, akuammidine, 19 S scholaricine, and 19,20 E vallesamine is fruit, since it shows highest amount of these alkaloids. Undoubtedly, NMR and statistical methods are very helpful to differentiate the profile of alkaloids in A. scholaris.
The Role of Ferritin in Health and Disease: Recent Advances and Understandings
Authors: Kotla Nikhil Kumar , Dutta Priyata , Parimi Sanjana , Das Nupur K.
Published: July 2022

Systemic iron homeostasis needs to be tightly controlled, as both deficiency and excess iron cause major global health concerns, such as iron deficiency anemia, hemochromatosis, etc. In mammals, sufficient dietary acquisition is critical for fulfilling the systemic iron requirement. New questions are emerging about whether and how cellular iron transport pathways integrate with the iron storage mechanism. Ferritin is the intracellular iron storage protein that stores surplus iron after all the cellular needs are fulfilled and releases it in the face of an acute demand. Currently, there is a surge in interest in ferritin research after the discovery of novel pathways like ferritinophagy and ferroptosis. This review emphasizes the most recent ferritin-related discoveries and their impact on systemic iron regulation.
Strain Rate Dependence of Compressive Mechanical Properties of Polyamide and Its Composite Fabricated Using Selective Laser Sintering under Saturated-Water Conditions
Authors: Zheng Xiaodong , Meng Jiahuan , Liu Yang
Published: July 2022

In this work, polyamide 12 (PA12) and carbon fiber reinforced polyamide 12 (CF/PA12) composites were fabricated using selective laser sintering (SLS), and the coupling effects of the strain rate and hygroscopicity on the compressive mechanical properties were investigated. The results showed that the CF/PA12 had a shorter saturation time and lower saturated water absorption under the same conditions, indicating that the SLS of CF/PA12 had lower hydrophilia and higher water resistance when compared to the SLS of PA12. It was observed that as the strain rate increased, and the ultimate compression strength and the yield strength monotonically increased with almost the same slope, indicating that the strain rate had the same positive correlation with the compressive strength of the SLS of PA12 and CF/PA12. The water immersion results showed a significant reduction of 15% in the yield strength of SLS of PA12, but not very significant in CF/PA12. This indicated that the carbon fiber was favorable for maintaining the mechanical properties of polyamide 12 after absorbing water. The findings in this work provide a basic knowledge of the mechanical properties of SLS polyamide under different loading and saturated-water conditions and thus is helpful to widen the application of SLS products in harsh environments.
Effect of the Oxidation Process on Carrier Lifetime and on SF Defects of 4H SiC Thick Epilayer for Detection Applications
Authors: Meli Alessandro , Muoio Annamaria , Reitano Riccardo , Sangregorio Enrico , Calcagno Lucia , Trotta Antonio , Parisi Miriam , Meda Laura , La Via Francesco
Published: July 2022

The aim of this work was a deep spectroscopical characterization of a thick 4H SiC epitaxial layer and a comparison of results between samples before and after a thermal oxidation process carried out at 1400 °C for 48 h. Through Raman and photoluminescence (PL) spectroscopies, the carrier lifetimes and the general status of the epilayer were evaluated. Time-resolved photoluminescence (TRPL) was used to estimate carrier lifetime over the entire 250 µm epilayer using different wavelengths to obtain information from different depths. Furthermore, an analysis of stacking fault defects was conducted through PL and Raman maps to evaluate how these defects could affect the carrier lifetime, in particular after the thermal oxidation process, in comparison with non-oxidated samples. This study shows that the oxidation process allows an improvement in the epitaxial layer performances in terms of carrier lifetime and diffusion length. These results were confirmed using deep level transient spectroscopy (DLTS) measurements evidencing a decrease in the Z1/2 centers, although the oxidation generated other types of defects, ON1 and ON2, which appeared to affect the carrier lifetime less than Z1/2 centers.
Temperature-Induced Internal Stress Influence on Specimens in Indentation Tests
Authors: Wang Shunbo , Li Xianke , Zhao Hongwei
Published: July 2022

The factors affecting the internal stress of specimens during indentation tests were investigated by finite element analysis (FEA) modelling. This was carried out to gain a qualitative understanding of the test errors introduced by the temperature environment during the indentation process. In this study, the influence of thermal expansion of fixed stage on upper specimen (currently neglected in temperature indentation) was explored in detail. Technical issues associated with the parameters of the specimen (such as thickness, width, and elastic modulus) and external conditions (such as stage and glue) were identified and addressed. The test error of the calculated hardness and elastic modulus of the specimen reached up to more than 3% simultaneously at −196 °C (temperature of liquid nitrogen). Based on these considerations, the preferred operation conditions were identified for testing in specific temperature environment. These results can guide experiments aimed at obtaining precise mechanical parameters.
Broadband Circular Polarised Printed Antennas for Indoor Wireless Communication Systems: A Comprehensive Review
Authors: Al-Gburi Ahmed Jamal Abdullah , Zakaria Zahriladha , Alsariera Hussein , Akbar Muhammad Firdaus , Ibrahim Imran Mohd , Ahmad Khalid Subhi , Ahmad Sarosh , Al-Bawri Samir Salem
Published: July 2022

With the rapid changes in wireless communication systems, indoor wireless communication (IWC) technology has undergone tremendous development. Antennas are crucial components of IWC systems that transmit and receive signals within indoor environments. Thus, the development of indoor technology is highly dependent on the development of indoor antennas. However, indoor environments with limited space require the fewest indoor antenna units and the smallest indoor antenna sizes possible. Hence, indoor antennas with compact size and broad applications have become widely preferred. In an IWC system, circularly polarised (CP) antennas are generally important, especially in dense indoor environments, because compared with linearly polarised (LP) antennas, CP antennas reduce polarisation mismatch and multipath losses. This paper combs through the existing studies related to three-dimensional (3D) geometry (nonplanar) or waveguide indoor antennas and the two common approaches to two-dimensional (2D) geometry (planar) indoor antennas, namely, broadband CP printed monopole antennas (BCPPMAs) and broadband CP printed slot antennas (BCPPSAs). The advantages, disadvantages and limitations of previous works are highlighted as well. These research works are summarised, compared and analysed to understand the recent specifications of BCPPMAs and BCPPSAs to generate the most appropriate design structure suitable for current IWC systems.
SAW Resonators and Filters Based on Sc0.43Al0.57N on Single Crystal and Polycrystalline Diamond
Authors: Sinusia Lozano Miguel , Fernández-García Laura , López-Romero David , Williams Oliver A. , Iriarte Gonzalo F.
Published: July 2022

The massive data transfer rates of nowadays mobile communication technologies demand devices not only with outstanding electric performances but with example stability in a wide range of conditions. Surface acoustic wave (SAW) devices provide a high Q-factor and properties inherent to the employed materials: thermal and chemical stability or low propagation losses. SAW resonators and filters based on Sc0.43Al0.57N synthetized by reactive magnetron sputtering on single crystal and polycrystalline diamond substrates were fabricated and evaluated. Our SAW resonators showed high electromechanical coupling coefficients for Rayleigh and Sezawa modes, propagating at 1.2 GHz and 2.3 GHz, respectively. Finally, SAW filters were fabricated on Sc0.43Al0.57N/diamond heterostructures, with working frequencies above 4.7 GHz and ~200 MHz bandwidths, confirming that these devices are promising candidates in developing 5G technology.
Listeria monocytogenes in Irrigation Water: An Assessment of Outbreaks, Sources, Prevalence, and Persistence
Authors: Gartley Samantha , Anderson-Coughlin Brienna , Sharma Manan , Kniel Kalmia E.
Published: July 2022

As more fresh fruits and vegetables are needed to meet the demands of a growing population, growers may need to start depending on more varied sources of water, including environmental, recycled, and reclaimed waters. Some of these sources might be susceptible to contamination with microbial pathogens, such as Listeria monocytogenes. Surveys have found this pathogen in water, soil, vegetation, and farm animal feces around the world. The frequency at which this pathogen is present in water sources is dependent on multiple factors, including the season, surrounding land use, presence of animals, and physicochemical water parameters. Understanding the survival duration of L. monocytogenes in specific water sources is important, but studies are limited concerning this environment and the impact of these highly variable factors. Understanding the pathogen’s ability to remain infectious is key to understanding how L. monocytogenes impacts produce outbreaks and, ultimately, consumers’ health.
Analysis of the Metabolic Response of Planktonic Cells and Biofilms of Klebsiella pneumoniae to Sublethal Disinfection with Sodium Hypochlorite Measured by NMR
Authors: Garcia Mendez David Felipe , Rengifo Herrera Julián Andrés , Sanabria Janeth , Wist Julien
Published: July 2022

Klebsiella pneumoniae is a pathogenic agent able to form biofilms on water storage tanks and pipe walls. This opportunistic pathogen can generate a thick layer as one of its essential virulence factors, enabling the bacteria to survive disinfection processes and thus develop drug resistance. Understanding the metabolic differences between biofilm and planktonic cells of the K. pneumoniae response to NaClO is key to developing strategies to control its spread. In this study, we performed an NMR metabolic profile analysis to compare the response to a sublethal concentration of sodium hypochlorite of biofilm and planktonic cells of K. pneumoniae cultured inside silicone tubing. Metabolic profiles revealed changes in the metabolism of planktonic cells after a contact time of 10 min with 7 mg L−1 of sodium hypochlorite. A decrease in the production of metabolites such as lactate, acetate, ethanol, and succinate in this cell type was observed, thus indicating a disruption of glucose intake. In contrast, the biofilms displayed a high metabolic heterogeneity, and the treatment did not affect their metabolic signature.
Revealing the Softening-Melting Behaviors and Slag Characteristics of Vanadium-Titanium Magnetite Burden with Various MgO Addition
Authors: Wang Bin , Zhao Wei , Zhang Xinghua , Hu Shaoyan , Guo Hongwei , Chu Mansheng
Published: July 2022

MgO addition plays an essential role in the blast furnace smelting process, including softening-melting characteristics and metallurgical properties of slag. In the present study, the effect of MgO distribution on the softening-melting characteristics and slag system of vanadium-titanium magnetite burden were explored by simulating BF conditions. The results show that the MgO flux addition significantly affects the crystallization temperature of slag-phase, the precipitated phase components, and slag viscosity. This indicates that appropriate MgO addition can improve the metallurgical properties of blast furnace slag effectively, thereby improving the softening-melting-dripping performance of the mixed burden. The V-Ti pellets with a MgO content higher than 2.40 wt% exhibit optimum metallurgical properties. With a constant MgO content in mixed burden, the softening-melting properties of composite burden could be improved effectively as the MgO partitioning scheme includes 1.90 wt% MgO in sinter and 3.02 wt% MgO in pellet.
Lead Isotopic Constraints on the Provenance of Antarctic Dust and Atmospheric Circulation Patterns Prior to the Mid-Brunhes Event (~430 kyr ago)
Authors: Han Changhee , Burn Laurie J. , Vallelonga Paul , Hur Soon Do , Boutron Claude F. , Han Yeongcheol , Lee Sanghee , Lee Ahhyung , Hong Sungmin
Published: July 2022

A lead (Pb) isotopic record, covering the two oldest glacial–interglacial cycles (~572 to 801 kyr ago) characterized by lukewarm interglacials in the European Project for Ice Coring in Antarctica Dome C ice core, provides evidence for dust provenance in central East Antarctic ice prior to the Mid-Brunhes Event (MBE), ~430 kyr ago. Combined with published post-MBE data, distinct isotopic compositions, coupled with isotope mixing model results, suggest Patagonia/Tierra del Fuego (TdF) as the most important sources of dust during both pre-MBE and post-MBE cold and intermediate glacial periods. During interglacials, central-western Argentina emerges as a major contributor, resulting from reduced dust supply from Patagonia/TdF after the MBE, contrasting to the persistent dominance of dust from Patagonia/TdF before the MBE. The data also show a small fraction of volcanic Pb transferred from extra-Antarctic volcanoes during post-MBE interglacials, as opposed to abundant transfer prior to the MBE. These differences are most likely attributed to the enhanced wet removal efficiency with the hydrological cycle intensified over the Southern Ocean, associated with a poleward shift of the southern westerly winds (SWW) during warmer post-MBE interglacials, and vice versa during cooler pre-MBE ones. Our results highlight sensitive responses of the SWW and the associated atmospheric conditions to stepwise Antarctic warming.
Extraction of Bioactive Components from Chamaenerion angustifolium (L.) Scop. with Choline Chloride and Organic Acids Natural Deep Eutectic Solvents
Authors: Tsvetov Nikita , Pasichnik Elena , Korovkina Anna , Gosteva Alevtina
Published: July 2022

Chamaenerion angustifolium (L.) Scop. (fireweed) is a perennial herbaceous plant of the Onagraceae family widely used in folk and scientific medicine. It is a promising source of bioactive components. One of the modern trends in extraction is the use of natural deep eutectic solvents (NADESs) combined with ultrasound-assisted extraction (UAE). However, works devoted to the extraction of biologically active substances from C. angustifolium using NADESs are scarce. The aim of this work is a comprehensive study of UAE of bioactive components from C. angustifolium using NADESs based on choline chloride and malonic, malic, tartaric, and citric acids. The antioxidative properties, total phenols, and flavonoids content were estimated for NADES-based extracts. The reference solvents were water and 90% v/v ethanol. Volatile extracted components were identified using GC-MS. The kinetics of the UAE were studied at 45 °C for 20–180 min with water added to 30 wt% NADES. The power of the ultrasound was 120 W, and the frequency was 40 kHz. It was found that NADES choline chloride + citric acid is more effective for the extraction of bioactive components. For this, NADES UAE conditions were optimized following a Box–Behnken design of the experiment and a response surface methodology. The temperature ranged from 30 to 60 °C, the time of extraction ranged from 20 to 60, and the addition of water ranged from 30 to 70 wt%. We established the optimal extraction conditions: temperature 58 °C, time of extraction 35 min, and 70 wt% water. The obtained results expand the knowledge about the use of NADES for the extraction of biologically active compounds from cheap and available plant raw materials.
Geochemical and Spatial Distribution of Topsoil HMs Coupled with Modeling of Cr Using Chemometrics Intelligent Techniques: Case Study from Dammam Area, Saudi Arabia
Authors: Yassin Mohamed A. , Tawabini Bassam , Al-Shaibani Abdulaziz , Adetoro John Adedapo , Benaafi Mohammed , AL-Areeq Ahmed M. , Usman A. G. , Abba S. I.
Published: July 2022

Unconsolidated earthen surface materials can retain heavy metals originating from different sources. These metals are dangerous to humans as well as the immediate environment. This danger leads to the need to assess various geochemical conditions of the materials. In this study, the assessment of topsoil materials’ contamination with heavy metals (HMs) was conducted. The material’s representative spatial samples were taken from various sources: agricultural, industrial, and residential areas. The materials include topsoil, eolian deposits, and other unconsolidated earthen materials. The samples were analyzed using the ICP-OES. The obtained results based on the experimental procedure indicated that the average levels of the heavy metals were: As (1.21 ± 0.69 mg/kg), Ba (110.62 ± 262 mg/kg), Hg (0.08 ± 0.18 mg/kg), Pb (6.34 ± 14.55 mg/kg), Ni (8.95 ± 5.66 mg/kg), V (9.98 ± 6.08 mg/kg), Cd (1.18 ± 4.33 mg/kg), Cr (31.79 ± 37.9 mg/kg), Cu (6.76 ± 12.54 mg/kg), and Zn (23.44 ± 84.43 mg/kg). Subsequently, chemometrics modeling and a prediction of Cr concentration (mg/kg) were performed using three different modeling techniques, including two artificial intelligence (AI) techniques, namely, generalized neural network (GRNN) and Elman neural network (Elm NN) models, as well as a classical multivariate statistical technique (MST). The results indicated that the AI-based models have a superior ability in estimating the Cr concentration (mg/kg) than MST, whereby GRNN can enhance the performance of MST up to 94.6% in the validation step. The concentration levels of most metals were found to be within the acceptable range. The findings indicate that AI-based models are cost-effective and efficient tools for trace metal estimations from soil.
Green Synthesis of Silver Nanoparticles Using the Plant Extract of Acer oblongifolium and Study of Its Antibacterial and Antiproliferative Activity via Mathematical Approaches
Authors: Naveed Muhammad , Bukhari Bakhtawar , Aziz Tariq , Zaib Sumera , Mansoor Muhammad Adil , Khan Ayaz Ali , Shahzad Muhammad , Dablool Anas S. , Alruways Mashael W. , Almalki Abdulraheem Ali , Alamri Abdulhakeem S. , Alhomrani Majid
Published: July 2022

In this study, the antibacterial and antifungal properties of silver nanoparticles synthesized with the aqueous plant extract of Acer oblongifolium leaves were defined using a simplistic, environmentally friendly, reliable, and cost-effective method. The aqueous plant extract of Acer oblongifolium, which served as a capping and reducing agent, was used to biosynthesize silver nanoparticles. UV visible spectroscopy, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and scanning electron microscopy were used to analyze the biosynthesized Acer oblongifolium silver nanoparticles (AgNPs). Gram-positive bacteria (Bacillus paramycoides and Bacillus cereus) and Gram-negative bacteria (E. coli) were used to test the AgNPs’ antibacterial activity. The presence of different functional groups was determined by FTIR. The AgNPs were rod-like in shape. The nanoparticles were more toxic against Escherichiacoli than both Bacillus cereus and Bacillus paramycoides. The AgNPs had IC50 values of 6.22 and 9.43 and mg/mL on HeLa and MCF-7, respectively, proving their comparatively strong potency against MCF-7. This confirmed that silver nanoparticles had strong antibacterial activity and antiproliferative ability against MCF-7 and HeLa cell lines. The mathematical modeling revealed that the pure nanoparticle had a high heat-absorbing capacity compared to the mixed nanoparticle. This research demonstrated that the biosynthesized Acer oblongifolium AgNPs could be used as an antioxidant, antibacterial, and anticancer agent in the future.
Safranal Induces Vasorelaxation by Inhibiting Ca2+ Influx and Na+/Ca2+ Exchanger in Isolated Rat Aortic Rings
Authors: Al-Saigh Noor Nadhim , Abdalla Shtaywy
Published: July 2022

Introduction: Safranal, which endows saffron its unique aroma, causes vasodilatation and has a hypotensive effect in animal studies, but the mechanisms of these effects are unknown. In this study, we investigated the mechanisms of safranal vasodilation. Methods: Isolated rat endothelium-intact or -denuded aortic rings were precontracted with phenylephrine and then relaxed with safranal. To further assess the involvement of nitric oxide, prostaglandins, guanylate cyclase, and phospholipase A2 in safranal-induced vasodilation, aortic rings were preincubated with L-NAME, indomethacin, methylene blue, or quinacrine, respectively, then precontracted with phenylephrine, and safranal concentration–response curves were established. To explore the effects of safranal on Ca2+ influx, phenylephrine and CaCl2 concentration–response curves were established in the presence of safranal. Furthermore, the effect of safranal on aortic rings in the presence of ouabain, a Na+-K+ ATPase inhibitor, was studied to explore the contribution of Na+/Ca2+ exchanger to this vasodilation. Results: Safranal caused vasodilation in endothelium-intact and endothelium-denuded aortic rings. The vasodilation was not eliminated by pretreatment with L-NAME, indomethacin, methylene blue, or quinacrine, indicating the lack of a role for NO/cGMP. Safranal significantly inhibited the maximum contractions induced by phenylephrine, or by CaCl2 in Ca2+-free depolarizing buffer. Safranal also relaxed contractions induced by ouabain, but pretreatment with safranal totally abolished the development of ouabain contractions. Discussion/Conclusion: Inhibition of Na+-K+ ATPase by ouabain leads to the accumulation of Na+ intracellularly, forcing the Na+/Ca2+ exchanger to work in reverse mode, thus causing a contraction. Inhibition of the development of this contraction by preincubation with safranal indicates that safranal inhibited the Na+/Ca2+ exchanger. We conclude that safranal vasodilation is mediated by the inhibition of calcium influx from extracellular space through L-type Ca2+ channels and by the inhibition of the Na+/Ca2+ exchanger.
Derhamnosylmaysin Inhibits Adipogenesis via Inhibiting Expression of PPARγ and C/EBPα in 3T3-L1 Cells
Authors: Cho Hang-Hee , Jang Sun-Hee , Won Chungkil , Kim Chung-Hui , Kim Hong-Duck , Kim Tae Hoon , Cho Jae-Hyeon
Published: July 2022

We investigated the effects of derhamnosylmaysin (DM) on adipogenesis and lipid accumulation in 3T3-L1 adipocytes. Our data showed that DM inhibited lipid accumulation and adipocyte differentiation in 3T3-L1 cells. Treatment of 3T3-L1 adipocytes with DM decreased the expression of major transcription factors, such as sterol regulatory element-binding protein-1c (SREBP-1c), the CCAAT-enhancer-binding protein (CEBP) family, and peroxisome proliferator-activated receptor gamma (PPARγ), in the regulation of adipocyte differentiation. Moreover, the expression of their downstream target genes related to adipogenesis and lipogenesis, including adipocyte fatty acid-binding protein (aP2), lipoprotein lipase (LPL), stearyl-CoA-desaturase-1 (SCD-1), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS), was also decreased by treatment with DM during adipogenesis. Additionally, DM attenuated insulin-stimulated phosphorylation of Akt. These results first demonstrated that DM inhibited adipogenesis and lipogenesis through downregulation of the key adipogenic transcription factors SREBP-1c, the CEBP family, and PPARγ and inactivation of the major adipogenesis signaling factor Akt, which is intermediated in insulin. These studies demonstrated that DM is a new bioactive compound for antiadipogenic reagents for controlling overweight and obesity.
Correction: Duburg et al. Composite Polybenzimidazole Membrane with High Capacity Retention for Vanadium Redox Flow Batteries. Molecules 2021, 26, 1679
Authors: Duburg Jacobus C. , Azizi Kobra , Primdahl Søren , Hjuler Hans Aage , Zanzola Elena , Schmidt Thomas J. , Gubler Lorenz
Published: July 2022

The authors wish to make the following changes to their paper [...]
Carbodiimide-Mediated Beckmann Rearrangement of Oxyma-B as a Side Reaction in Peptide Synthesis
Authors: Orlandin Andrea , Guryanov Ivan , Ferrazzano Lucia , Biondi Barbara , Biscaglia Francesca , Storti Claudia , Rancan Marzio , Formaggio Fernando , Ricci Antonio , Cabri Walter
Published: July 2022

The suppression of side reactions is one of the most important objectives in peptide synthesis, where highly reactive compounds are involved. Recently, the violuric acid derivative Oxyma-B was introduced into peptide synthesis protocols as a promising additive to efficiently control the optical purity of the amino acids prone to racemization. However, we discovered a side reaction involving the Beckmann rearrangement of Oxyma-B during the coupling reaction, which compromises the yield and purity of the target peptides. Here, we present the investigation of the mechanism of this rearrangement and the optimization of the coupling reaction conditions to control it. These results can be taken into account for the design of novel efficient oxime-based coupling reagents.
Synthesis of Pyrimidine Conjugates with 4-(6-Amino-hexanoyl)-7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine and Evaluation of Their Antiviral Activity
Authors: Krasnov Victor P. , Musiyak Vera V. , Levit Galina L. , Gruzdev Dmitry A. , Andronova Valeriya L. , Galegov Georgii A. , Orshanskaya Iana R. , Sinegubova Ekaterina O. , Zarubaev Vladimir V. , Charushin Valery N.
Published: July 2022

A series of pyrimidine conjugates containing a fragment of racemic 7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine and its (S)-enantiomer attached via a 6-aminohexanoyl fragment were synthesized by the reaction of nucleophilic substitution of chlorine in various chloropyrimidines. The structures of the synthesized compounds were confirmed by 1H, 19F, and 13C NMR spectral data. Enantiomeric purity of optically active derivatives was confirmed by chiral HPLC. Antiviral evaluation of the synthesized compounds has shown that the replacement of purine with a pyrimidine fragment leads to a decrease in the anti-herpesvirus activity compared to the lead compound, purine conjugate. The studied compounds did not exhibit significant activity against influenza A (H1N1) virus.
Variation in the Content of Bioactive Compounds in Infusions Prepared from Different Parts of Wild Polish Stinging Nettle (Urtica dioica L.)
Authors: Jeszka-Skowron Magdalena , Zgoła-Grześkowiak Agnieszka , Frankowski Robert , Grześkowiak Tomasz , Jeszka Anna Maria
Published: July 2022

Nettle is a common plant that offers many health benefits and is grown all over the world. The content of active compounds in roots, stems, and leaves was determined based on the extraction procedure optimized using the Central Composite Design. Flavonols, phenolic acids, trigonelline, nicotinamide, nicotinic acids, and short-chain organic acids were determined with the use of LC–MS/MS and capillary isotachophoresis. Trigonelline, which was not previously reported in the roots and stems of nettle, was found in all parts of the plant and considerable variations in its content were observed (2.8–108 µg g−1). Furthermore, the Principal Component Analysis taking into account more variables demonstrated differences in the content of bioactive components between roots and aerial parts of nettle.