bluuebunny/crossref_metadata_2025 huggingface dataset:
Climate Change and Adaptive Management: Case Study in Agriculture, Forestry and Pastoral Areas
Authors: Xuan Xin , Liu Bing , Zhang Fan
Published: August 2021

Adaptive management has very important practical significance for climate change adaptation and will play a great role in climate change risk mitigation in agricultural, forestry, and pastoral areas of China. Based on the theory of adaptive management, this paper selects Yuanping City from Shanxi Province, Qingyuan County from Liaoning Province, and Kulun Banner from Inner Mongolia as representative cases in agricultural, forestry, and pastoral areas, respectively, to carry out field research, and it uses 1970–2017 meteorological station data to apply vulnerability assessment and climate element change trend analysis, combined with the meteorological hazards data, and explore the adaptive management measures for agricultural, forestry, and pastoral areas in China. The conclusions are as follows: (1) the vulnerability of precipitation in Yuanping is high, the increase in temperature and drought and floods are the most important factors affecting crop yields in agricultural areas, and the key to climate change adaptive management lies in the awareness of farmers of climate change risks and the institutional guarantee of the government; (2) Qingyuan has high temperature vulnerability, and the forest areas have relatively strong adaptive capacity to climate change, but climate change will significantly affect the forest’s carbon sequestration function, and the focus of climate change adaptive management in the forestry sector is on engineering and technology field practices; (3) Kulun has the highest vulnerability to climate change, the frequent meteorological disasters seriously impact livestock development, and climate change adaptive management in pastoral areas relies on the participation of pastoralists’ local knowledge and also needs the support of the government and society.
Spatial–Temporal Pattern and Influence Factors of Land Used for Transportation at the County Level since the Implementation of the Reform and Opening-Up Policy in China
Authors: Li Baochao , Cao Xiaoshu , Xu Jianbin , Wang Wulin , Ouyang Shishu , Liu Dan
Published: August 2021

In this paper, we study the characteristics of the spatial–temporal pattern of land used for transportation at the county level since the implementation of the reform and opening-up policy in China and discuss the factors that influence the spatial differences between lands used for transportation in order to provide a reference for the formulation of traffic policies. The authors used ArcGIS spatial analysis, an ordinary least squares (OLS) regression model, and a geographic detector model based on the data of the transportation network at the county level in China from 1978 to 2018. We obtained the following results: (1) The land used for transportation at the county level in China is divided by the Hu Huanyong Line, which is characterized by spatial variation, where the southeastern region is higher than the northwestern region. (2) Counties with a high proportion of land used for transportation show obvious changes, characterized by the transformation from the “corridor” zonal distribution of arteries to the “diamond” group distribution of major city clusters, reducing the gap in land used for transportation at the county level in China. (3) The level of industrialization, per capita gross regional product (PGRP), and ratio of the non-agricultural working population all have an incentivizing impact on the increase in land used for transportation at the county level in China. We conclude that the land used for transportation at the county level in China is jointly decided by the economy, industry, and population. Therefore, we believe that it is necessary to promote fast economic growth, the upgrading of industrial structures, and population density to achieve the balanced development of land used for transportation at the county level in China.
Acceleration of Soil Erosion by Different Land Uses in Arid Lands above 10Be Natural Background Rates: Case Study in the Sonoran Desert, USA
Authors: Jeong Ara , Dorn Ronald I. , Seong Yeong-Bae , Yu Byung-Yong
Published: August 2021

Land use changes often lead to soil erosion, land degradation, and environmental deterioration. However, little is known about just how much humans accelerate erosion compared to natural background rates in non-agricultural settings, despite its importance to knowing the magnitude of soil degradation. The lack of understanding of anthropogenic acceleration is especially true for arid regions. Thus, we used 10Be catchment averaged denudation rates (CADRs) to obtain natural rates of soil erosion in and around the Phoenix metropolitan region, Arizona, United States. We then measured the acceleration of soil erosion by grazing, wildfire, and urban construction by comparing CADRs to erosion rates for the same watersheds, finding that: (i) grazing sometimes can increase sediment yields by up to 2.3–2.6x, (ii) human-set wildfires increased sediment yields by up to 9.7–10.4x, (iii) after some post-fire vegetation recovered, sediment yield was then up to 4.2–4.5x the background yield, (iv) construction increased sediment yields by up to 5.0–5.6x, and (v) the sealing of urban surfaces led to one-tenth to one-half of the background sediment yields. The acceleration of erosion at the urban–rural interface in arid lands highlights the need for sustainable management of arid-region soils.
Rapid Reclamation and Degradation of Suaeda salsa Saltmarsh along Coastal China’s Northern Yellow Sea
Authors: Zhang Jing , Zhang Yan , Lloyd Huw , Zhang Zhengwang , Li Donglai
Published: August 2021

Suaeda salsa saltmarshes are an important coastal wetland habitat of China’s northern Yellow Sea, which plays a critical role in sequestering carbon (blue carbon), protecting shorelines, maintaining biodiversity, and has substantial economic value (e.g., ecotourism). However, the area of S. salsa has been rapidly declining due to several different threats from reclamation and invasive species that impact its natural succession. Here, we map the changes in the distribution of the S. salsa saltmarshes along the northern Yellow Sea of China (NYSC) at 5-year intervals by applying the supervised maximum likelihood method to analyze Landsat images from 1988 to 2018 and investigate the potential impact of three important factors on habitat change by analyzing the temporal changes in S. salsa saltmarshes with other land covers. S. salsa saltmarsh areas have decreased by 63% (264 km2 ha to 99 km2), and the average loss of S. salsa saltmarshes was 5.5 km2/year along the NYSC over the past three decades. There have been many dramatic declines in the two main distribution areas of S. salsa saltmarshes with a 77% loss of habitat area in Liaodong Bay (from 112 km2 to 26 km2) and a 52% loss in the Yellow River Delta wetland-Guangli-Zhima estuarine wetland (from 137 km2 to 65 km2). Land reclamation is the most important impact factor in the loss of S. salsa saltmarshes, while there have been limited effects of natural succession and smooth cordgrass (Spartina alterniflora) invasion. In light of the important ecological services and economic value of the S. salsa habitat, emergency conservation actions (e.g., habitat restoration, strictly supervision) are needed to limit the rapid habitat loss, which should include the immediate cessation of extensive land reclamation along the NYSC.
Association between Activity and Brain-Derived Neurotrophic Factor in Patients with Non-Alcoholic Fatty Liver Disease: A Data-Mining Analysis
Authors: Hashida Ryuki , Nakano Dan , Yamamura Sakura , Kawaguchi Takumi , Tsutsumi Tsubasa , Matsuse Hiroo , Takahashi Hirokazu , Gerber Lynn , Younossi Zobair M. , Torimura Takuji
Published: August 2021

Reduction in activity links to the development and progression of non-alcoholic fatty liver disease (NAFLD). Brain-derived neurotrophic factor (BDNF) is known to regulate an activity. We aimed to investigate the association between reduction in activity and BDNF in patients with NAFLD using data-mining analysis. We enrolled 48 NAFLD patients. Patients were classified into reduced (n = 21) or normal activity groups (n = 27) based on the activity score of the Chronic Liver Disease Questionnaire-NAFLD/non-alcoholic steatohepatitis. Circulating BDNF levels were measured using an enzyme-linked immunoassay. Factors associated with reduced activity were analyzed using decision-tree and random forest analyses. A reduction in activity was seen in 43.8% of patients. Hemoglobin A1c and BDNF were identified as negative independent factors for reduced activity (hemoglobin A1c, OR 0.012, p = 0.012; BDNF, OR 0.041, p = 0.039). Decision-tree analysis showed that “BDNF levels ≥ 19.1 ng/mL” was the most important classifier for reduced activity. In random forest analysis, serum BDNF level was the highest-ranked variable for distinguishing between the reduced and normal activity groups (158 valuable importance). Reduced activity was commonly seen in patients with NAFLD. Data-mining analyses revealed that BNDF was the most important independent factor corresponding with the reduction in activity. BDNF may be an important target for the prevention and treatment of NAFLD.
Density, Enthalpy of Vaporization and Local Structure of Neat N-Alkane Liquids
Authors: Lindberg Gerrick E. , Baker Joseph L. , Hanley Jennifer , Grundy William M. , King Caitlin
Published: August 2021

The properties of alkanes are consequential for understanding many chemical processes in nature and industry. We use molecular dynamics simulations with the Amber force field GAFF2 to examine the structure of pure liquids at each respective normal boiling point, spanning the 15 n-alkanes from methane to pentadecane. The densities predicted from the simulations are found to agree well with reported experimental values, with an average deviation of 1.9%. The enthalpies of vaporization have an average absolute deviation from experiment of 10.4%. Radial distribution functions show that short alkanes have distinct local structures that are found to converge with each other with increasing chain length. This provides a unique perspective on trends in the n-alkane series and will be useful for interpreting similarities and differences in the n-alkane series as well as the breakdown of ideal solution behavior in mixtures of these molecules.
(±)-2-{[4-(4-Bromophenyl)-5-phenyl-4H-1,2,4-triazol-3-yl]sulfanyl}-1-phenyl-1-ethanol
Authors: Vorga Milenca Mariana , Badea Valentin
Published: August 2021

The novel racemic secondary alcohol (±)-2-{[4-(4-bromophenyl)-5-phenyl-4H-1,2,4-triazol-3-yl]sulfanyl}-1-phenyl-1-ethanol (12) has been successfully synthesized through S-alkylation of 4-(4-bromophenyl)-5-phenyl-4H-1,2,4-triazole-3-thiol (10) in alkaline medium with 2-bromo-1-phenylethanone followed by reduction of the corresponding ketone 11. All the synthesized compounds were characterized by IR, 1D (1H, 13C, DEPT135) and 2D (1H-1H, 1H-13C and 1H-15N) NMR spectroscopy, elemental analysis and HRMS spectrometry.
Osteoblast-like Cell Proliferation, ALP Activity and Photocatalytic Activity on Sintered Anatase and Rutile Titanium Dioxide
Authors: Yokoi Yukiko
Published: August 2021

This study aimed to create a biomaterial from titanium dioxide (TiO2), which has been known to have photocatalytic and bone formation promoting effects. I expected that anatase titanium dioxide-based implants could promote bone augmentation and induce bone formation. Powdery anatase TiO2 was compression molded and sintered at 700, 800, 900, and 1000 °C to prepare sintered compact samples. X-ray diffraction and scanning electron microscopy were used to observe the surface of these samples. Furthermore, mouse osteoblast-like cells (MC3T3-E1 cell line) were seeded on the samples sintered at different temperatures, and cell proliferation was observed to evaluate the cell proliferation of the samples. The sample sintered at 700 °C was composed of anatase TiO2. The samples sintered at 800 °C and 900 °C were confirmed to consist of a mixture of anatase and rutile TiO2 crystalline phases. Moreover, the sample sintered at 700 and 800 °C, which contained anatase TiO2, showed remarkable photocatalytic activity. Those samples sintered at 1000 °C were transformed to the rutile TiO2. The cell proliferation after 7–14-days culturing revealed that cells cultured on the 700 °C sample decreased in number immediately after initiation of culturing. The cells cultured on TiO2 sintered at 900 °C markedly proliferated over time with an increase in the alkaline phosphatase activity, showing good MC3T3-E1 cell compatibility of the samples. The sample sintered at 1000 °C, which is rutile TiO2, showed the highest increase.
Prognosis of Regenerative Endodontic Procedures in Mature Teeth: A Systematic Review and Meta-Analysis of Clinical and Radiographic Parameters
Authors: Scelza Pantaleo , Gonçalves Fabiano , Caldas Isleine , Nunes Fernanda , Lourenço Emanuelle Stellet , Tavares Sandro , Magno Marcela , Pintor Andrea , Montemezzi Pietro , Edoardo Emanuele Di , Mourão Carlos Fernando de Almeida Barros , Alves Gutemberg , Scelza Miriam Zaccaro
Published: August 2021

This work aimed to investigate the use of Regenerative Endodontic Procedures (REP) on the treatment of pulp necrosis in mature teeth through systematic review and meta-analysis of evidence on clinical and radiographic parameters before and after REP. A search was performed in different databases on 9 September 2020, including seven clinical studies and randomized controlled trials (RCT). The methodological quality was assessed using Revised Cochrane risk-of-bias (RoB 2) and Before-and-After tools. Meta-analyses were performed to evaluate the success incidences regarding the reduction of periapical lesion and recovery of sensitivity. The certainty of the evidence was assessed using GRADE. Meta-analysis showed a high overall success of 0.95 (0.92, 0.98) I2 = 6%, with high periapical lesion reduction at 12 months (0.93 (0.86, 0.96) I2 = 37%) and by the end of follow-up (0.91 (0.83, 0.96) I2 = 13%). Lower incidences of positive sensitivity response were identified for the electrical (0.58 (0.46, 0.70) I2 = 51%) and cold tests (0.70 (0.54, 0.84) I2 = 68%). The calculated levels of REP success were similar to those reported for immature teeth. With a very low certainty of evidence, the meta-analysis showed a high incidence of REP’s success for mature teeth with necrotic pulp evidenced by periapical lesion reduction and moderate positive responses to sensitivity tests.
Recent Progress in the Development of Advanced Functionalized Electrodes for Oxygen Evolution Reaction: An Overview
Authors: Chen Tse-Wei , Kalimuthu Palraj , Anushya Ganesan , Chen Shen-Ming , Mariyappan Vinitha , Ramachandran Rasu
Published: August 2021

Presently, the global energy demand for increasing clean and green energy consumption lies in the development of low-cost, sustainable, economically viable and eco-friendly natured electrochemical conversion process, which is a significant advancement in different morphological types of advanced electrocatalysts to promote their electrocatalytic properties. Herein, we overviewed the recent advancements in oxygen evolution reactions (OERs), including easy electrode fabrication and significant action in water-splitting devices. To date, various synthetic approaches and modern characterization techniques have effectively been anticipated for upgraded OER activity. Moreover, the discussed electrode catalysts have emerged as the most hopeful constituents and received massive appreciation in OER with low overpotential and long-term cyclic stability. This review article broadly confers the recent progress research in OER, the general mechanistic approaches, challenges to enhance the catalytic performances and future directions for the scientific community.
The Effect of Inclusions on a Medium Temperature Transformation Microstructure and Toughness of High-Strength HSLA Steel
Authors: Yang Yang , Zhao Xian-Ming , Li Hao , Zhao Xiao-Yu , Han Huai-Bin
Published: August 2021

In this study, the evolution of high-strength HSLA steel microstructure was studied using high-temperature laser confocal microscopy and SEM, TEM, and EPMA techniques. The effect of precipitates on grain boundary migration of austenite during high-temperature heating and the effect of inclusions in undercooled austenite on AF phase transformation were studied. The effect of multiphase microstructure on impact toughness was studied by Gleeble thermal simulation at 550, 600, and 650 °C. The results show that the austenite grain is refined by TiN pinning at high temperatures, and a large number of NbC and VCN are precipitated in ferrite for precipitation strengthening. The (Ti-Mn-O) + (Al + Si + Mn-O) + MnS composite inclusions with smaller sizes have a greater promoting effect on the nucleation of acicular ferrite than single-phase MnS. With a decrease in isothermal temperature, the content of acicular ferrite increases. When the isothermal temperature is 550 °C, an increase in the maximum impact toughness of acicular ferrite with large-angle grain boundary is clearly observable.
Effect of Finely Ground Limestone and Dolomite on Compression Strength and Reduction Swelling of Vanadium-Titanium Pellets
Authors: Liu Hao , Peng Shihong , Zhang Ke , Qin Yuelin , Meng Fei , He Wenchao , Liu Weiqiang , Chen Min , Yan Lixiang
Published: August 2021

Vanadium−titanium magnetite (VTM) is an important raw material for ironmaking under the situation of increasingly demanding scarce resources. To further improve the metallurgical properties of pellets, and to satisfy the requirements of blast furnace slag basicity, finely ground dolomite and limestone have been added to the pellet. In this study, the effect of finely ground dolomite and limestone on the metallurgical properties (green pellet drop strength, cold compression strength, reduction swelling index, and microscopic mineral structure) of VTM pellets were investigated. With the addition of finely ground dolomite and limestone, the drop strength of the green pellet was improved. The effect of adding finely ground limestone was greater than adding finely ground dolomite. Adding more finely ground dolomite and limestone compared to pellets without limestone and dolomite, the cold compression strength was decreased, which was attributed to the decomposition of limestone and dolomite during the induration of pellets. With the addition of dolomite, the reduction swelling index (RSI) increased firstly and then decreased. When the basicity of the pellet was 0.54 to 0.94, the slag phase with the lowest melting point was formed, corresponding to the maximum of the reduction swelling index. For the pellets with added limestone, the reduction swelling of the pellets deteriorated. The reduction index of the pellets increased and reached the maximum (26.6%) at a basicity of 1.54, which belongs to abnormal swelling.
Dendrite Pattern Formation of Sodium Chloride Crystal
Authors: Suematsu Nobuhiko J. , Iwamoto Junpei , Ishii Yuya , Yamamoto Akira
Published: August 2021

A variety of crystal structures is found in nature, not only equilibrium structures reflecting molecular structures, but also non-equilibrium structures which depend on the physicochemical conditions occurring during the crystal growth. In this paper, we focus on the dendrite structure of sodium chloride (NaCl) formed by the simple evaporation of an aqueous NaCl solution. The characteristics of the growth structures were measured as a function of the initial concentration of NaCl. In addition, the crystal growth process was measured using optical microscopy. As a result, the growth rate was not constant but was found to oscillate over time and synchronize with the wetting of the crystal. Our observations indicate that dendrite structures are more easily generated at higher initial concentrations. The detailed mechanism for dendrite pattern formation is still under investigation.
On the Decrease in Transformation Stress in a Bicrystal Cu-Al-Mn Shape-Memory Alloy during Cyclic Compressive Deformation
Authors: Su Tung-Huan , Lu Nian-Hu , Chen Chih-Hsuan , Chen Chuin-Shan
Published: August 2021

The evolution of the inhomogeneous distribution of the transformation stress (σs) and strain fields with an increasing number of cycles in two differently orientated grains is investigated for the first time using a combined technique of digital image correlation and data-driven identification. The theoretical transformation strains (εT) of these two grains with crystal orientations [5 3 26]β and [6 5 11]β along the loading direction are 10.1% and 7.1%, respectively. The grain with lower εT has a higher σs initially and a faster decrease in σs compared with the grain with higher εT. The results show that the grains with higher σs might trigger more dislocations during the martensite transformation, and thus result in greater residual strain and a larger decrease in σs during subsequent cycles. Grain boundary kinking in bicrystal induces an additional decrease in transformation stress. We conclude that a grain with crystal orientation that has high transformation strain and low transformation stress (with respect to loading direction) will exhibit stable transformation stress, and thus lead to higher functional performance in Cu-based shape memory alloys.
Boosting Piezo/Photo-Induced Charge Transfer of CNT/Bi4O5I2 Catalyst for Efficient Ultrasound-Assisted Degradation of Rhodamine B
Authors: Wang Yang , Yu Dongfang , Liu Yue , Liu Xin , Shi Yue
Published: August 2021

Strain-induced internal electric fields present a significant path to boosting the separation of photoinduced electrons and holes. In addition, piezo-induced positive/negative pairs could be released smoothly, taking advantage of the excellent electroconductibility of some conductors. Herein, the hybrid piezo-photocatalysis is constructed by combining debut piezoelectric nanosheets (Bi4O5I2) and typical conductor multiwalled carbon nanotubes (CNT). The photocatalytic degradation efficiency that the hybrid CNT/Bi4O5I2 exhibits was remarkably increased by more than 2.3 times under ultrasonic vibration, due to the piezo-generated internal electric field. In addition, the transient photocurrent spectroscopy and electrochemical impedance measurement reveal that the CNT coating on Bi4O5I2 enhances the piezo-induced positive/negative migration. Therefore, the piezocatalytic activity of CNT/Bi4O5I2 could be improved by three times, compared with pure Bi4O5I2 nanosheets. Our results may offer promising approaches to sketching efficient piezo-photocatalysis for the full utilization of solar energy or mechanical vibration.
Computing the Fatigue Life of Cold Spray Repairs to Simulated Corrosion Damage
Authors: Peng Daren , Tang Caixian , Matthews Neil , Jones Rhys , Kundu Sudip , Raman R. K. Singh , Alankar Alankar
Published: August 2021

This paper summarises the findings of an investigation into the durability of cold spray repairs, also known as supersonic particle deposition or SPD repairs, to simulated corrosion damage in AA7075-T7351 aluminium alloy specimens. A feature of this paper is that it is the first to show how to perform the mandatory durability analysis of repaired corroded structures, where the corroded material is first removed by machining and then repaired using cold spray, in a fashion consistent with the requirements delineated in USAF Structures Bulletin EZ-19-01, MIL-STD-1530D, and the US Joint Services Structural Guidelines JSSG2006.
Replacement Process of Carbonate Apatite by Alveolar Bone in a Rat Extraction Socket
Authors: Zhang Xiaoxu , Atsuta Ikiru , Narimatsu Ikue , Ueda Nobuyuki , Takahashi Ryosuke , Egashira Yuki , Zhang Jing-Qi , Gu Jiong-Yan , Koyano Kiyoshi , Ayukawa Yasunori
Published: August 2021

The objective of this study was to investigate a bone graft substitute containing carbonate apatite (CO3Ap) to analyze bone replacement and the state of bone formation in vitro and in vivo compared with autogenous bone (AB) or control. An osteoclast precursor cell line was cultured with AB or CO3Ap, and morphological analysis using scanning electron microscopy and a tartrate-resistant acid phosphatase activity assay were performed. The right maxillary first and second molars of Wistar rats were extracted and compensated by AB or CO3Ap granules. Following implantation, the bone formation state was evaluated after 3, 5, 7, 14, and 28 days of surgery by micro-computed tomography and immunohistostaining. The osteoclast-like cell morphology was typical with many cell protrusions in the AB and CO3Ap groups. Additionally, the number of osteoclast-like cells formed in the culture increased in each group; however, there was no significant difference between the AB and CO3Ap groups. Five days after tooth extraction, osteoclasts were observed near CO3Ap. The bone thickness in the CO3Ap group was significantly increased than that in the control group and the bone formation in the CO3Ap group increased by the same level as that in the AB group. CO3Ap is gradually absorbed by osteoclasts in the extraction socket and is easily replaced by alveolar bone. The process of bone replacement by osteoclasts is similar to that of autologous bone. By observing the process of bone replacement in more detail, it may be possible to gain a better understanding of the bone formation and control the amount of bone after surgery.
Determination of Mechanical and Tribological Properties of Silicone-Based Composites Filled with Manganese Waste
Authors: Mrówka Maciej , Woźniak Anna , Nowak Jerzy , Wróbel Gabriel , Sławski Sebastian
Published: August 2021

High-tonnage industrial processes generate high amount of waste. This is a growing problem in the whole world. Neutralizing such waste can be time consuming and costly. One of the possibilities of their reuse is to use them as fillers in polymer composites. Introduction of the filler in polymer matrix causes change in its mechanical and tribological properties. In the article, the effect of introducing fillers from post-production waste, and its effect on changing the physical properties of silicone-based composites filled with manganese (II) oxide and waste manganese residue was investigated. The composites were made by gravity casting. Composites with 2.5, 5, 7.5, and 10 wt% of the fillers were examined. The composite materials were subjected to tests such as: density, hardness, resilience, tensile test, abrasion resistance, and ball-on-disc. Microscopic images showed that, the particles of the fillers are uniformly distributed in silicone matrix with the formation of smaller agglomerates. Such agglomerates introduced a discontinuity in the structure of the polymer material, which caused a decrease in the tensile strength and elongation at break for all tested compositions in comparison with the mechanical properties of the silicone used as the matrix. However, it was found that all silicone-based composites filled with manganese (II) oxide and manganese residue showed a reduction in abrasive wear, compared to the reference sample.
FLUKA Simulations of Kβ/Kα Intensity Ratios of Copper in Ag–Cu Alloys
Authors: Gójska Aneta , Kozioł Karol , Kozioł Karol , Wasilewski Adam , Wasilewski Adam , Miśta-Jakubowska Ewelina , Miśta-Jakubowska Ewelina , Mazerewicz Piotr , Mazerewicz Piotr , Szymanowski Jakub , Szymanowski Jakub
Published: August 2021

The numerical simulations of Cu Kα and Cu Kβ fluorescence lines induced by Rh X-ray tube and by monoenergetic radiation have been presented. The copper Kβ/Kα intensity ratios for pure elements as well as for Ag–Cu alloys have been modeled. The results obtained by use of the FLUKA code, based on the Monte-Carlo approach, have been compared to available experimental and theoretical values. A visible relationship was found between the simulated Kβ/Kα intensity ratios and the copper content of the Ag–Cu alloy: as the Cu content increases, the Kβ/Kα coefficient decreases. The results can play role in elemental material analysis, especially in archaeometry.
Kinematics, Speed, and Anthropometry-Based Ankle Joint Torque Estimation: A Deep Learning Regression Approach
Authors: Moreira Luís , Figueiredo Joana , Vilas-Boas João Paulo , Santos Cristina Peixoto
Published: August 2021

Powered Assistive Devices (PADs) have been proposed to enable repetitive, user-oriented gait rehabilitation. They may include torque controllers that typically require reference joint torque trajectories to determine the most suitable level of assistance. However, a robust approach able to automatically estimate user-oriented reference joint torque trajectories, namely ankle torque, while considering the effects of varying walking speed, body mass, and height on the gait dynamics, is needed. This study evaluates the accuracy and generalization ability of two Deep Learning (DL) regressors (Long-Short Term Memory and Convolutional Neural Network (CNN)) to generate user-oriented reference ankle torque trajectories by innovatively customizing them according to the walking speed (ranging from 1.0 to 4.0 km/h) and users’ body height and mass (ranging from 1.51 to 1.83 m and 52.0 to 83.7 kg, respectively). Furthermore, this study hypothesizes that DL regressors can estimate joint torque without resourcing electromyography signals. CNN was the most robust algorithm (Normalized Root Mean Square Error: 0.70 ± 0.06; Spearman Correlation: 0.89 ± 0.03; Coefficient of Determination: 0.91 ± 0.03). No statistically significant differences were found in CNN accuracy (p-value > 0.05) whether electromyography signals are included as inputs or not, enabling a less obtrusive and accurate setup for torque estimation.
An Almost Comprehensive Approach for the Choice of Motor and Transmission in Mechatronic Applications: Torque Peak of the Motor
Authors: Cusimano Giancarlo , Casolo Federico
Published: August 2021

The choice of motor and transmission to move a joint must ensure that the torque peaks of the motor lie inside its dynamic operating range. With this aim, this paper proposes an approach in which all the candidate transmissions are processed one by one to find among all the candidate motors those they could execute the reference task with. Consequently, all the transmission parameters, and not only its transmission ratio, are taken into consideration in advance. For rectangular dynamic operating ranges, this approach allows a direct and precise evaluation of all the admissible motor-transmission couples, without any approximation and further check. Apart from an entirely automated procedure, the method also provides diagrams through which the designer can concisely compare the admissible solutions. Furthermore, the method provides a solution for the drive systems in which the limit torque of the dynamic operating range does depend on the motor speed.
Time-Inhomogeneous Feller-Type Diffusion Process in Population Dynamics
Authors: Giorno Virginia , Nobile Amelia G.
Published: August 2021

The time-inhomogeneous Feller-type diffusion process, having infinitesimal drift α(t)x+β(t) and infinitesimal variance 2r(t)x, with a zero-flux condition in the zero-state, is considered. This process is obtained as a continuous approximation of a birth-death process with immigration. The transition probability density function and the related conditional moments, with their asymptotic behaviors, are determined. Special attention is paid to the cases in which the intensity functions α(t), β(t), r(t) exhibit some kind of periodicity due to seasonal immigration, regular environmental cycles or random fluctuations. Various numerical computations are performed to illustrate the role played by the periodic functions.
Designing Color Symmetry in Stigmergic Art
Authors: Richter Hendrik
Published: August 2021

Color symmetry is an extension of the symmetry imposed by isometric transformations and indicates that the colors of geometrical objects are assigned according to the symmetry properties of these objects. A color symmetry permutes the coloring of the objects consistently with their symmetry group. We apply this concept to bio-inspired generative art. Therefore, the geometrical objects are interpreted as motifs that may repeat themselves with a symmetry-consistent coloring. The motifs are obtained by design principles from stigmergy. We discuss the design procedure and present visual results.
Variances and Logarithmic Aggregation Operators: Extended Tools for Decision-Making Processes
Authors: Gómez Monge Rodrigo , Galeana Figueroa Evaristo , Alfaro-García Víctor G. , Merigó José M. , Yager Ronald R.
Published: August 2021

Variance, as a measurement of dispersion, is a basic component of decision-making processes. Recent advances in intelligent systems have included the concept of variance in information fusion techniques for decision-making under uncertainty. These dispersion measures broaden the spectrum of decision makers by extending the toolset for the analysis and modeling of problems. This paper introduces some variance logarithmic averaging operators, including the variance generalized ordered weighted averaging (Var-GOWLA) operator and the induced variance generalized ordered weighted averaging (Var-IGOWLA) operator. Moreover, this paper analyzes some properties, families and particular cases of the proposed operators. Finally, an illustrative example of the characteristic design of the operators is proposed using real-world information retrieved from financial markets. The objective of this paper is to analyze the performance of some equities based on the expected payoff and the dispersion of its elements. Results show that the equity payoff results present diverse rankings combined with the proposed operators, and the introduced variance measures aid decision-making by offering new tools for information analysis. These results are particularly interesting when selecting logarithmic averaging operators for decision-making processes. The approach presented in this paper extends the available tools for decision-making under ignorance, uncertainty, and subjective environments.
Synthesizing Various Organic Polyacid Compounds for Modifying Forward Osmosis Membranes to Enhance Separation Performance
Authors: Lin Yi-Li , Samannan Bharath , Tung Kuo-Lun , Thavasikani Jeyabalan , Dong Cheng-Di , Chen Chiu-Wen , Wu Chung-Hsin , Cheng Yu-Rong
Published: August 2021

In order to overcome the challenges of low permeate flux (Jp) and the accompanying reverse solute flux (JS) during the forward osmosis (FO) membrane separation process, we synthesized four hybrid materials of polyacid-based organic compounds and incorporated them into the selective polyamide (PA) layer to make novel thin-film nanocomposite (TFN) FO membranes. The Jp and JS of each membrane were evaluated and used along with membrane selectivity (Jp/JS) as indicators of membrane separation performance. The fabricated and modified membranes were also characterized for ridge and valley surface morphologies with increasing hydrophilicity and finger-shaped parallel channels in the PSf substrate. Moreover, two highly hydrophilic nanoparticles of graphene oxide (GO) and titanium oxide (TiO2) were introduced with the hybrid materials for PA modification, which can further enhance the Jp of the TFN membranes. The highest Jp of the TFN membranes achieved 12.1 L/m2-h using 0.1% curcumin-acetoguanamine @ cerium polyacid (CATCP) and 0.0175% GO. The characteristic peaks of the hybrid materials were detected on the membrane surface using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, evidencing successful incorporation of the hybrid materials during membrane modification. Here, we present the novel TFN membranes using hybrid materials for separation applications. The reactions for synthesizing the hybrid materials and for incorporating them with PA layer are proposed.
Research and Development Journey and Future Trends of Hollow Fiber Membranes for Purification Applications (1970–2020): A Bibliometric Analysis
Authors: Ayub Muhammad , Othman Mohd Hafiz Dzarfan , Kadir Siti Hamimah Sheikh Abdul , Ali Adnan , Khan Imran Ullah , Yusop Mohd Zamri Mohd , Matsuura Takeshi , Fauzi Ismail Ahmad , A. Rahman Mukhlis , Jaafar Juhana
Published: August 2021

Hollow fiber membrane (HFM) technology has received significant attention due to its broad range separation and purification applications in the industry. In the current study, we applied bibliometric analysis to evaluate the global research trends on key applications of HFMs by evaluating the global publication outputs. Results obtained from 5626 published articles (1970–2020) from the Scopus database were further manipulated using VOSviewer software through cartography analysis. The study emphasizes the performance of most influential annual publications covering mainstream journals, leading countries, institutions, leading authors and author’s keywords, as well as future research trends. The study found that 62% of the global HFM publications were contributed by China, USA, Singapore, Japan and Malaysia, followed by 77 other countries. This study will stimulate the researchers by showing the future-minded research directions when they select new research areas, particularly in those related to water treatment, biomedical and gas separation applications of HFM.
Function-Related Dynamics in Multi-Spanning Helical Membrane Proteins Revealed by Solution NMR
Authors: Takeuchi Koh , Kofuku Yutaka , Imai Shunsuke , Ueda Takumi , Tokunaga Yuji , Toyama Yuki , Shiraishi Yutaro , Shimada Ichio
Published: August 2021

A primary biological function of multi-spanning membrane proteins is to transfer information and/or materials through a membrane by changing their conformations. Therefore, particular dynamics of the membrane proteins are tightly associated with their function. The semi-atomic resolution dynamics information revealed by NMR is able to discriminate function-related dynamics from random fluctuations. This review will discuss several studies in which quantitative dynamics information by solution NMR has contributed to revealing the structural basis of the function of multi-spanning membrane proteins, such as ion channels, GPCRs, and transporters.
Effect on Microstructure and Performance of B4C Content in B4C/Cu Composite
Authors: Shu Dayu , Li Xiuqing , Yang Qingxia
Published: August 2021

In this paper, boron carbide (B4C) ceramics were added to a copper (Cu) base, to improve the mechanical properties and wear resistance of pure copper. The B4C/Cu composites with different B4C contents, were obtained by mechanical mixing and discharge plasma sintering methods. Scanning electron microscopy (SEM), energy spectrum analysis (EDS), and electron probe microanalysis (EPMA) were used, to observe and analyze the microstructures of the B4C/Cu composites. The influences of the B4C content on the hardness, density, conductivity, and wear resistance were also studied. The experimental results show that B4C has an important effect on Cu. With increasing B4C content, both the density and conductivity of the B4C/Cu composites gradually decrease. The hardness of the Cu-15 wt.% B4C composite has the highest value, 86 HBW (Brinell hardness tungsten carbide ball indenter), which is 79.2% higher than that of pure copper. However, when the B4C amount increases to 20 wt.%, the hardness decreases due to the metallic connection being weakened in the material. The Cu-15 wt.% B4C composite has the lowest volume loss, indicating that it has the best wear resistance. Analyses of worn B4C/Cu composite surfaces suggest that deep and narrow grooves, as well as sharp ridges, appear on the worn pure Cu surface, but on the worn Cu-15 wt.% B4C composite surface, the furrows become shallow and few. In particular, ridge formation cannot be found on the worn Cu-15 wt.% B4C composite surface, which represents the enhancement in wear resistance.
N-acetyltaurine and Acetylcarnitine Production for the Mitochondrial Acetyl-CoA Regulation in Skeletal Muscles during Endurance Exercises
Authors: Miyazaki Teruo , Nakamura-Shinya Yuho , Ebina Kei , Komine Shoichi , Ra Song-Gyu , Ishikura Keisuke , Ohmori Hajime , Honda Akira
Published: August 2021

During endurance exercises, a large amount of mitochondrial acetyl-CoA is produced in skeletal muscles from lipids, and the excess acetyl-CoA suppresses the metabolic flux from glycolysis to the TCA cycle. This study evaluated the hypothesis that taurine and carnitine act as a buffer of the acetyl moiety of mitochondrial acetyl-CoA derived from the short- and long-chain fatty acids of skeletal muscles during endurance exercises. In human subjects, the serum concentrations of acetylated forms of taurine (NAT) and carnitine (ACT), which are the metabolites of acetyl-CoA buffering, significantly increased after a full marathon. In the culture medium of primary human skeletal muscle cells, NAT and ACT concentrations significantly increased when they were cultured with taurine and acetate or with carnitine and palmitic acid, respectively. The increase in the mitochondrial acetyl-CoA/free CoA ratio induced by acetate and palmitic acid was suppressed by taurine and carnitine, respectively. Elevations of NAT and ACT in the blood of humans during endurance exercises might serve the buffering of the acetyl-moiety in mitochondria by taurine and carnitine, respectively. The results suggest that blood levels of NAT and ACT indicate energy production status from fatty acids in the skeletal muscles of humans undergoing endurance exercise.
Introducing Metamodel-Based Global Calibration of Material-Specific Simulation Parameters for Discrete Element Method
Authors: Richter Christian , Will Frank
Published: August 2021

An important prerequisite for the generation of realistic material behavior with the Discrete Element Method (DEM) is the correct determination of the material-specific simulation parameters. Usually, this is done in a process called calibration. One main disadvantage of classical calibration is the fact that it is a non-learning approach. This means the knowledge about the functional relationship between parameters and simulation responses does not evolve over time, and the number of necessary simulations per calibration sequence respectively per investigated material stays the same. To overcome these shortcomings, a new method called Metamodel-based Global Calibration (MBGC) is introduced. Instead of performing expensive simulation runs taking several minutes to hours of time, MBGC uses a metamodel which can be computed in fractions of a second to search for an optimal parameter set. The metamodel was trained with data from several hundred simulation runs and is able to predict simulation responses in dependence of a given parameter set with very high accuracy. To ensure usability for the calibration of a wide variety of bulk materials, the variance of particle size distributions (PSD) is included in the metamodel via parametric PSD-functions, whose parameters serve as additional input values for the metamodel.
Study on Phase Transfer Catalyst Used in the Synthesis of Sodium Isobutyl Xanthate
Authors: Ma Zhijun , Cheng Liang , Weng Xingyuan , Gao Ye , Huang Jiuxing
Published: August 2021

Xanthates are by far the most widely used collectors in the froth flotation beneficiation of sulfide ores. However, the xanthate production process suffers from low yield, low productivity, long reaction time and environmental pollution. To address these issues, an effective method was developed for the synthesis of xanthates using phase transfer catalyst. Sodium isobutyl xanthate was synthesized from isobutyl alcohol ((CH3)2CHCH2OH), sodium hydroxide (NaOH) and carbon disulfide (CS2) with dichloromethane (CH2Cl2) as solvent and cetyltrimethylammonium bromide (CTAB), cetyltrimethylammonium chloride (CTAC), tetrabutylammonium bromide (TBAB) and tetrabutylammonium chloride (TBAC) as phase transfer catalyst. The compound was characterized by elemental analysis, infrared spectrum, 1H NMR and 13C NMR. The influencing factors on the content and yield of sodium isobutyl xanthate including phase transfer catalyst type, phase transfer catalyst dosage and reaction time were studied by single-factor experiments. The influencing factors on the product purity and yield including reaction temperature, solvent volume, material ratio and rotating speed were studied by orthogonal experiments. The results showed that when the amount of TBAC was 3.0%malcohol, the reaction temperature was 35 °C, the solvent volume was 3.5 Valcohol, the rotating speed was 180 rpm, the reaction time was 4 h and the material ratio was n[(CH3)2CHCH2OH]:n(NaOH):n(CS2) = 1:1:1.10, the product yield could be up to 86.66% and the product purity reached 82.56%.
Study of Pigments from the Colonial Convent of Actopan, Hidalgo, Mexico
Authors: Ortega-Lazcano Jesús Benjamín , Mendoza-Anaya Demetrio , Salinas-Rodríguez Eleazar , Hernández-Ávila Juan , Acevedo-Sandoval Otilio Arturo , Rodríguez-Lugo Ventura
Published: August 2021

In this work, scanning electron microscopy (SEM), X-ray diffraction (XRD), and infrared spectroscopy (FTIR) techniques were used to study blue, red, and ochre pigments from wall paintings of the 16th century colonial convent of San Nicolás de Tolentino in Actopan, Hidalgo, Mexico. In the blue pigments, nanometric fibers with a chemical composition of mostly O, Si, Al, and Mg were identified. XRD and FTIR analysis indicated the presence of palygorskite clay, which suggests that these analyzed blue pigments are similar to Mayan blue. In the red pigment, structures with different morphologies (spines and flake shapes, for instance), with a composition of C, O, Al, Si, S, Ca, Na, Mg, and K and a higher concentration of Fe and Pb, were observed. Complementary analysis showed that the red color originates from hematite and lead. Finally, the ochre pigment showed a significant presence of O and Fe, which was associated with the goethite mineral, while calcite was a crystalline phase identified in all analyzed pigments; these show that these pigments are characteristic of the known Mexican Colonial color palette.
Effect of Encapsulated Beet Extracts (Beta vulgaris) Added to Yogurt on the Physicochemical Characteristics and Antioxidant Activity
Authors: Flores-Mancha Martha A. , Ruíz-Gutiérrez Martha G. , Sánchez-Vega Rogelio , Santellano-Estrada Eduardo , Chávez-Martínez América
Published: August 2021

Beet has been used as an ingredient for functional foods due to its high antioxidant activity, thanks to the betalains it contains. The effects of the addition of beet extract (liquid and lyophilized) on the physicochemical characteristics, color, antioxidant activity (AA), total betalains (TB), total polyphenols (TP), and total protein concentration (TPC) were evaluated on stirred yogurt. The treatments (T1-yogurt natural, T2-yogurt added with beet juice, T3-added extract of beet encapsulated with maltodextrin, and T4-yogurt added with extract of beet encapsulated with inulin) exhibited results with significant differences (p < 0.05). The highest TB content was observed in T2 (209.49 ± 14.91), followed by T3 (18.65 ± 1.01) and later T4 (12.96 ± 0.55). The highest AA was observed on T2 after 14 days (ABTS˙ 0.819 mM TE/100 g and DPPH˙ 0.343 mM TE/100 g), and the lowest was found on T1 at day 14 (ABTS˙ 0.526 mM TE/100 g and DPPH˙ 0.094 mM TE/100 g). A high content of TP was observed (7.13 to 9.79 mg GAE/g). The TPC varied between 11.38 to 12.56 µg/mL. The addition of beet extract significantly increased AA in yogurt, betalains being the main compounds responsible for that bioactivity.