bluuebunny/crossref_metadata_2025 huggingface dataset:
Type II DNA Topoisomerases Cause Spontaneous Double-Strand Breaks in Genomic DNA
Authors: Morimoto Suguru , Tsuda Masataka , Bunch Heeyoun , Sasanuma Hiroyuki , Austin Caroline , Takeda Shunichi
Published: October 2019

Type II DNA topoisomerase enzymes (TOP2) catalyze topological changes by strand passage reactions. They involve passing one intact double stranded DNA duplex through a transient enzyme-bridged break in another (gated helix) followed by ligation of the break by TOP2. A TOP2 poison, etoposide blocks TOP2 catalysis at the ligation step of the enzyme-bridged break, increasing the number of stable TOP2 cleavage complexes (TOP2ccs). Remarkably, such pathological TOP2ccs are formed during the normal cell cycle as well as in postmitotic cells. Thus, this ‘abortive catalysis’ can be a major source of spontaneously arising DNA double-strand breaks (DSBs). TOP2-mediated DSBs are also formed upon stimulation with physiological concentrations of androgens and estrogens. The frequent occurrence of TOP2-mediated DSBs was previously not appreciated because they are efficiently repaired. This repair is performed in collaboration with BRCA1, BRCA2, MRE11 nuclease, and tyrosyl-DNA phosphodiesterase 2 (TDP2) with nonhomologous end joining (NHEJ) factors. This review first discusses spontaneously arising DSBs caused by the abortive catalysis of TOP2 and then summarizes proteins involved in repairing stalled TOP2ccs and discusses the genotoxicity of the sex hormones.
Testosterone Degradative Pathway of Novosphingobium tardaugens
Authors: Ibero Juan , Galán Beatriz , Díaz Eduardo , García José L.
Published: October 2019

In this work, we have shown that Novosphingobium tardaugens NBRC 16725 (strain ARI-1), a bacterial strain that was isolated due to its capacity to mineralize the estrogenic endocrine compound 17β-estradiol, is also able to mineralize testosterone, the androgenic endocrine compound. Using in silico analysis, we predicted a new putative steroid degradation (SD) gene cluster in strain ARI-1, which resembles genes involved in testosterone degradation in Comamonas testosteroni and other testosterone degrading bacteria like Actinobacteria (like Rhodococcus and Mycobacteria genera) although with significant differences in gene organization. A whole transcriptomic analysis of N. tardaugens revealed that testosterone produces a limited induction of the genes of the SD cluster that show a high basal expression in its absence. The 3β/17β-hydroxysteroid dehydrogenase involved in the first metabolic step of testosterone degradation was identified by using genetic and biochemical approaches. The construction of knockout mutant strains in the genes of the SD cluster together with in silico analyses suggests the existence of gene redundancy in the genome of N. tardaugens. This work will expand the knowledge about the metabolic pathways and biotransformation capabilities of a Gram-negative bacterium that could become a new model system in the bacterial steroid degradation field.
Endolithic Microbial Habitats Hosted in Carbonate Nodules Currently Forming within Sediment at a High Methane Flux Site in the Sea of Japan
Authors: Yanagawa Katsunori , Shiraishi Fumito , Tanigawa Yusuke , Maeda Toshinari , Mustapha Nurul Asyifah , Owari Satoko , Tomaru Hitoshi , Matsumoto Ryo , Kano Akihiro
Published: October 2019

Concretionary carbonates in deep-sea methane seep fields are formed as a result of microbial methane degradation, called anaerobic oxidation of methane (AOM). Recently, active microorganisms, including anaerobic methanotrophic archaea, were discovered from methane seep-associated carbonate outcroppings on the seafloor. However sedimentary buried carbonate nodules are a hitherto unknown microbial habitat. In this study, we investigated the microbial community structures in two carbonate nodules collected from a high methane flux site in a gas hydrate field off the Oki islands in the Sea of Japan. The nodules were formed around sulfate-methane interfaces (SMI) corresponding to 0.7 and 2.2 m below the seafloor. Based on a geochemical analysis, light carbon isotopic values ranging from −54.91‰ to −37.32‰ were found from the nodules collected at the shallow SMI depth, which were attributed to the high contributions of AOM-induced carbonate precipitation. Signatures of methanotrophic archaeal populations within the sedimentary buried nodule were detected based on microbial community composition analyses and quantitative real-time PCR targeted 16S rRNA, and functional genes for AOM. These results suggest that the buried carbonate nodule currently develops AOM-related microbial communities, and grows depending on the continued AOM under high methane flux conditions.
Using Cilioplankton as an Indicator of the Ecological Condition of Aquatic Ecosystems
Authors: Kondrateva Tatiana , Nikonenkova Tatiana , Stepanova Nadezhda
Published: October 2019

We assess the quality of surface water in water bodies located in the Middle Volga region (Russian Federation). The water quality is assessed using 19 chemical compounds and cilioplankton indicators, such as the total number of species, the abundance of each species, and, based on both of them, the saprobity index and the Shannon–Weaver diversity index (H). We classify the water quality from polluted to extremely dirty by using abiotic indicators, and from conditionally clean to dirty by means of biotic indicators. Using the logistic regression method, we are able to predict the water quality (clean or dirty) in correspondence with the species diversity index (H) and to clarify how the quality of the water is related to its physicochemical properties. The seven most significant chemical predictors of both natural origin (mineralization, hydro carbonates, and chlorides) and natural-anthropogenic origin (organic substances (according to BOD5), nitrates, total petroleum hydrocarbons, iron), identified during the stepwise selection procedure, have a substantial influence on the outcome of the model. Qualitative and quantitative indicators of development of ciliates, as well as indices calculated on their basis, allow assessing with a very high level of accuracy the water quality and the condition of aquatic ecosystems in general. The Shannon index calculated for the number of ciliates can be successfully used for ranking water bodies as “clean/dirty”.
Multiscale Modeling of Glacial Loading by a 3D Thermo-Hydro-Mechanical Approach Including Erosion and Isostasy
Authors: Cerroni Daniele , Penati Mattia , Porta Giovanni , Miglio Edie , Zunino Paolo , Ruffo Paolo
Published: October 2019

We present a computational framework that allows investigating the Thermo-Hydro- Mechanical response of a representative part of a sedimentary basin during a glaciation cycle. We tackle the complexity of the problem, arising by the mutual interaction among several phenomena, by means of a multi-physics, multi-scale model with respect to both space and time. Our contribution addresses both the generation of the computational grid and the algorithm for the numerical solution of the problem. In particular we present a multi-scale approach accounting for the global deformation field of the lithosphere coupled with the Thermo-Hydro-Mechanical feedback of the ice load on a representative part of the domain at a finer scale. In the fine scale model we also include the erosion possibly caused by the ice melting. This methodology allows investigating the evolution of the sedimentary basin as a response to glaciation cycle at a fine scale, taking also into account the large spatial scale movement of the lithosphere due to isostasy. The numerical experiments are based on the analysis of simple scenario, and show the emergence of effects due to the multi-physics nature of the problem that are barely captured by simpler approaches.
Assessment of Radon Concentration and Impact on Human Health in a Region Dominated by Abandoned Gold Mine Tailings Dams: A Case from the West Rand Region, South Africa
Authors: Moshupya Paballo , Abiye Tamiru , Mouri Hassina , Levin Mannie , Strauss Marius , Strydom Rian
Published: October 2019

Radon gas has long been identified as a human carcinogen. The purpose of this study was to understand the occurrence of radon gas in the West Rand region, located west of the city of Johannesburg, South Africa, and to investigate its potential health effects. In this study, the sampling of rocks, tailings, and construction materials was carried out for geochemical analyses. For characterisation of radon, 60 radon monitors (RGMs) were installed in indoor and outdoor environments. The results showed that mine tailings contain high uranium levels, with a maximum of 149.76 ppm and a mean value of 48.87 ppm. The radon levels in the area ranged between 32 Bq/m3 and 1069 Bq/m3 and thus, exceed the typical outdoor radon levels of about 10 Bq/m3. Significantly high values were obtained from gold tailings dams. In indoor environments, radon concentration ranged up to a maximum of 174 Bq/m3, which is above the recommended value of 100 Bq/m3. The effective doses calculated from the obtained radon levels showed a maximum of 16 mSv/y, which is above the recommended value of 1 mSv/y proposed for public exposure. The estimated doses have an enormous potential to pose high lung cancer risks to the populations residing nearby tailings.
Deterministic Methodology for Determining the Optimal Sampling Frequency of Water Quality Monitoring Systems
Authors: Al-Khafaji Mahmoud Saleh
Published: October 2019

This paper proposes a novel deterministic methodology for estimating the optimal sampling frequency (SF) of water quality monitoring systems. The proposed methodology is based on employing two-dimensional contaminant transport simulation models to determine the minimum SF, taking into consideration all the potential changes in the boundary conditions of a water body. Two-dimensional contaminant transport simulation models (RMA4) were implemented to estimate the distribution patterns of some effective physiochemical parameters within the Al-Hammar Marsh in the southern part of Iraq for 30 cases of potential boundary conditions. Using geographical information system (GIS) tools, a spatiotemporal analysis approach was applied to the results of the RMA4 models to determine the minimum SF of the monitoring stations with a monitoring accuracy (MA) level of detectable change in contaminant concentration ranging from the standard level to 50% (stepwise 5%). For the study area, the proposed methodology specified a minimum and maximum SF for each monitoring station (MS) that ranged between 12 and 33 times per year, respectively. An exponential relationship between SF and MA was obtained. This relationship shows that increasing the MA to ±10%, ±25%, and ±50% increases the SF by approximately 14%, 28%, and 93%, respectively. However, the proposed methodology includes all the potential values and cases of flow and contaminant transport boundary conditions, which increases the certainty of monitoring the system and the efficiency of the SF schedule. Moreover, the proposed methodology can be effectively applied to all types of surface water resources.
A Retrospective Investigation on Age and Gender Differences of Injuries in DanceSport
Authors: Premelč Jerneja , Vučković Goran , James Nic , Dimitriou Lygeri
Published: October 2019

In spite of the extensive research on incidence site and type of injury in ballet and modern dancers, limited studies on injury in DanceSport have been reported. Therefore, this study determined retrospectively (within last 12 months) incidence, severity, site and type of injury, between gender and age-class in DanceSport. Participants were 97 international sport-dancers (female, 41; male, 56). Sixty-six (69%) dancers reported 96 injuries (1.00 (range = 4)) injuries per dancer) and an injury incidence of 1.7 (range = 14) per 1000 h. Females revealed significantly higher median injury incidence (females, 2.6 (range = 14); males, 1.9 (range = 9), p < 0.05) than males. A total of 61.5% of all injuries recorded were traumatic with a significant gender difference (Wald chi-square = 11.616, df = 1, p < 0.01). Injury severity was 3 (range 240) days with an interaction effect between gender and age-class (Wald chi-square = 251.374, df = 3, p < 0.001). Meanwhile, 72.3% of the dancers reported not including sport specific exercises besides dancing. These findings show gender and age-class differences in injury incidence, type and severity. Therefore, to reduce the likelihood of injuries, the implementation of supplemental DanceSport specific exercises that also considers the gender and age-class anatomical, functional, and choreographic demand differences in the training program should be recognized.
Modelling Economic Growth, Carbon Emissions, and Fossil Fuel Consumption in China: Cointegration and Multivariate Causality
Authors: Lv Zhihui , Chu Amanda M. Y. , McAleer Michael , Wong Wing-Keung
Published: October 2019

Most authors apply the Granger causality-VECM (vector error correction model), and Toda–Yamamoto procedures to investigate the relationships among fossil fuel consumption, CO 2 emissions, and economic growth, though they ignore the group joint effects and nonlinear behaviour among the variables. In order to circumvent the limitations and bridge the gap in the literature, this paper combines cointegration and linear and nonlinear Granger causality in multivariate settings to investigate the long-run equilibrium, short-run impact, and dynamic causality relationships among economic growth, CO 2 emissions, and fossil fuel consumption in China from 1965–2016. Using the combination of the newly developed econometric techniques, we obtain many novel empirical findings that are useful for policy makers. For example, cointegration and causality analysis imply that increasing CO 2 emissions not only leads to immediate economic growth, but also future economic growth, both linearly and nonlinearly. In addition, the findings from cointegration and causality analysis in multivariate settings do not support the argument that reducing CO 2 emissions and/or fossil fuel consumption does not lead to a slowdown in economic growth in China. The novel empirical findings are useful for policy makers in relation to fossil fuel consumption, CO 2 emissions, and economic growth. Using the novel findings, governments can make better decisions regarding energy conservation and emission reductions policies without undermining the pace of economic growth in the long run.
Exploring the Characteristics of an Intra-Urban Bus Service Network: A Case Study of Shenzhen, China
Authors: Yang Xiping , Lu Shiwei , Zhao Weifeng , Zhao Zhiyuan
Published: October 2019

The urban bus service system is one of the most important components of a public transport system. Thus, exploring the spatial configuration of the urban bus service system promotes an understanding of the quality of bus services. Such an understanding is of great importance to urban transport planning and policy making. In this study, we investigated the spatial characteristics of an urban bus service system by using the complex network approach. First, a three-step workflow was developed to collect a bus operating dataset from a public website. Then, we utilized the P-space method to represent the bus service network by connecting all bus stop pairs along each bus line. With the constructed bus network, a set of network analysis indicators were calculated to quantify the role of nodes in the network. A case study of Shenzhen, China was implemented to understand the statistical properties and spatial characteristics of the urban bus network configuration. The empirical findings can provide insights into the statistical laws and distinct convenient areas in a bus service network, and consequently aid in optimizing the allocation of bus stops and routes.
Investigating Contextual Effects on Burglary Risks: A Contextual Effects Model Built Based on Bayesian Spatial Modeling Strategy
Authors: Liu Hongqiang , Zhu Xinyan , Zhang Dongying , Liu Zhen
Published: October 2019

A contextual effects model, built based on Bayesian spatial modeling strategy, was used to investigate contextual effects on neighborhood burglary risks in Wuhan, China. The contextual effects denote the impact of the upper-level area on the lower-level units of analysis. These effects are often neglected in Bayesian spatial crime analysis. The contextual effects model accounts for the effects of independent variables, overdispersion, spatial autocorrelation, and contextual effects. Both the contextual effects model and the conventional Bayesian spatial model were fitted to our data. Results showed the two models had almost the same deviance information criterion (DIC). Furthermore, they identified the same set of significant independent variables and gave very similar estimates for burglary risks. Nonetheless, the contextual effects model was preferred in the sense that it provides insights into contextual effects on crime risks. Based on the contextual effects model and the map decomposition technique, we identified, worked out, and mapped the relative contribution of the neighborhood characteristics and contextual effects on the overall burglary risks. The research contributes to the increasing literature on modeling crime data by Bayesian spatial approaches.
Exploiting the Potential of VGI Metadata to Develop A Data-Driven Framework for Predicting User’s Proficiency in OpenStreetMap Context
Authors: Rajaram Gangothri , Manjula KR
Published: October 2019

Volunteered geographic information (VGI) encourages citizens to contribute geographic data voluntarily that helps to enhance geospatial databases. VGI’s significant limitations are trustworthiness and reliability concerning data quality due to the anonymity of data contributors. We propose a data-driven model to address these issues on OpenStreetMap (OSM), a particular case of VGI in recent times. This research examines the hypothesis of evaluating the proficiency of the contributor to assess the credibility of the data contributed. The proposed framework consists of two phases, namely, an exploratory data analysis phase and a learning phase. The former explores OSM data history to perform feature selection, resulting in “OSM Metadata” summarized using principal component analysis. The latter combines unsupervised and supervised learning through K-means for user-clustering and multi-class logistic regression for user classification. We identified five major classes representing user-proficiency levels based on contribution behavior in this study. We tested the framework with India OSM data history, where 17% of users are key contributors, and 27% are unexperienced local users. The results for classifying new users are satisfactory with 95.5% accuracy. Our conclusions recognize the potential of OSM metadata to illustrate the user’s contribution behavior without the knowledge of the user’s profile information.
Neurofilament Heavy Chain and Tau Protein Are Not Elevated in Cerebrospinal Fluid of Adult Patients with Spinal Muscular Atrophy during Loading with Nusinersen
Authors: Totzeck Andreas , Stolte Benjamin , Kizina Kathrin , Bolz Saskia , Schlag Melina , Thimm Andreas , Kleinschnitz Christoph , Hagenacker Tim
Published: October 2019

Nusinersen is the first approved drug for the treatment of spinal muscular atrophy (SMA). Treatment of SMA with nusinersen is based on a fixed dosing regimen. For other motoneuron diseases, such as amyotrophic lateral sclerosis (ALS), biomarkers are available for clinical diagnostics; however, no such biomarkers have yet been found for SMA. Serum and cerebrospinal fluid (CSF) samples of 11 patients with adult SMA type 3 were prospectively collected and analyzed during loading with nusinersen. Neurofilament heavy chain, tau protein, S100B protein, and neuron-specific enolase were investigated as potential biomarkers of motor neuron destruction. No significant pathological alterations in levels of neurofilament heavy chain, tau protein, or S100B protein were detected in the CSF or blood samples under baseline conditions or during loading with nusinersen. Neuron-specific enolase was marginally elevated in CSF and blood samples without significant alteration during treatment. In a mixed cohort of adult patients with SMA type 3, neurofilament heavy chain, tau protein, S100B protein, and neuron-specific enolase do not serve as potential biomarkers during the loading phase of nusinersen. The slow progression rate of SMA type 3 may not lead to detectable elevation of levels of these common markers of axonal degradation.
Glucagon Regulation of Energy Expenditure
Authors: Kleinert Maximilian , Sachs Stephan , Habegger Kirk M. , Hofmann Susanna M. , Müller Timo D.
Published: October 2019

Glucagon’s ability to increase energy expenditure has been known for more than 60 years, yet the mechanisms underlining glucagon’s thermogenic effect still remain largely elusive. Over the last years, significant efforts were directed to unravel the physiological and cellular underpinnings of how glucagon regulates energy expenditure. In this review, we summarize the current knowledge on how glucagon regulates systems metabolism with a special emphasis on its acute and chronic thermogenic effects.
Extracellular HtrA2 Induces Apoptosis in Human Umbilical Vein Endothelial Cells
Authors: Kaur Gurpinder , Stallmann Daniela , Schanze Nancy , Laumann Rosmarie , Heger Lukas Andreas , Steinfurt Johannes , Stachon Peter , Peter Karlheinz , Bode Christoph , Moser Martin , Ahrens Ingo , Duerschmied Daniel , Hortmann Marcus
Published: October 2019

The serine protease high-temperature-required protein A2 (HtrA2) has been identified as a key intracellular molecule promoting apoptosis in cells during ischemia reperfusion (IR) injury. IR injury in ST-segment elevation myocardial infarction (STEMI) contributes to overall myocardial damage. HtrA2 has further been shown to be significantly increased in the serum of patients with STEMI. In the present pilot study, we use human umbilical vein endothelial cells (HUVECs) to investigate whether extracellular HtrA2 induces apoptosis using Annexin V staining. Furthermore, we examine whether HtrA2 is released extracellularly after staurosporine-induced apoptosis using ELISA. We find that HtrA2 is released upon induction of apoptosis by staurosporine into the cell culture medium. Furthermore, treatment of HUVECs with extracellular HtrA2-induces apoptosis, while the addition of anti-HtrA2 antibodies reduces both HtrA2- and staurosporine-induced endothelial cell apoptosis. In conclusion, we show here that extracellular HtrA2 induces apoptosis in human endothelial cells, although the exact molecular mechanisms have to be investigated in future.
Hydrodynamic Performance of Submerged Plates During Focused Waves
Authors: Fang Qinghe , Yang Can , Guo Anxin
Published: October 2019

Submerged horizontal plates are widely employed in research of wave structure interaction as a simplification of coastal and ocean engineering structures. The hydrodynamic performance of submerged horizontal plates under focused waves has been seldom reported. Based on potential flow theory, this paper presents a general solution of the hydrodynamic pressure and wave forces exerted on submerged plates by a focused wave group. An existing experiment and two limiting cases are used to validate the accuracy of the present analytical model. With the validated model, the effect of wave properties and the configuration of the wave structure system on the hydrodynamic performance of submerged plates are investigated. It is found that the hydrodynamic performance of submerged horizontal plates varies with incident focused wave with different peak frequencies. The structural breadth significantly changes the hydrodynamic performance while the structural height has little influence. This paper shows the usefulness of potential flow theory for the preliminary calculation of wave loads on coastal and ocean engineering structures generated by focused waves.
Impulsive Delayed Lasota–Wazewska Fractional Models: Global Stability of Integral Manifolds
Authors: Stamov Gani , Stamova Ivanka
Published: October 2019

In this paper we deal with the problems of existence, boundedness and global stability of integral manifolds for impulsive Lasota–Wazewska equations of fractional order with time-varying delays and variable impulsive perturbations. The main results are obtained by employing the fractional Lyapunov method and comparison principle for impulsive fractional differential equations. With this research we generalize and improve some existing results on fractional-order models of cell production systems. These models and applied technique can be used in the investigation of integral manifolds in a wide range of biological and chemical processes.
Development of Preform for Simulation of Cold Forging Process of A V8 Engine Camshaft Free from Flash & Under-Filling
Authors: Saquib A.N. , Khaleed H.M.T. , Badruddin Irfan Anjum , Algahtani Ali , Addas M.F. , Abdullah A.B. , Athani Abdulgaphur , Kamangar Sarfaraz , Khan T.M. Yunus
Published: October 2019

Finite Element Method based techniques apply to a wide spectrum of engineering applications including manufacturing. The flexibility to achieve optimized results by simulations adds another dimension to process-development. The efficiency due to simulation is enhanced many folds for developing desired components by reducing the cost as well as time. This paper investigates cold forging process to be adopted to produce camshafts with a target to minimize flash as well as under filling. These two factors being major problems encountered when cold forging is to be adopted for complex shaped products. The current work is primarily concerned with the development of an optimized preform design for a V8 engine camshaft. The work involved the Solid modeling of the camshaft on AutoCAD and further analyzing the developed model through finite element analysis using Deform 3D. The analysis involved understanding of metal flow, volumetric analysis and die stresses in the forging process. The materials considered for the work-piece and the dies are AISI 8620 and AISI-H-26 respectively. The sample camshaft was taken from a standard Dodge Challenger V8 engine. 10 different cases are analyzed to find out the best possible scenario. It is fund that the stress level for the developed model was very much within the design limit of the material.
Texture Evolution and Anisotropy of Plastic Flow in Hot Compression of Extruded ZK60-T5 Magnesium Alloy Plate
Authors: Dharmendra Chalasani , Jain Mukesh , Prasad Yellapregada , Pitcheswara Rao Kamineni
Published: October 2019

The texture evolution during hot compression of extruded ZK60A-T5 magnesium alloy plate loaded along the extrusion direction (ED) and the normal direction (ND) has been examined with the help of pole figures obtained on specimens deformed in the ranges of 200 °C to 500 °C and 0.0003 s−1 to 10 s−1. The results are interpreted in terms of the operating slip systems and mechanisms identified based on processing maps developed for the above two initial specimen orientations. The processing map for the initial ED orientation exhibited three domains. In Domains 1 and 3, first-order pyramidal slip {10 1 ¯ l} <11 2 ¯ 0> occurs, while in Domain 2, second-order pyramidal slip {11 2 ¯ 2} <11 2 ¯ 3> occurs. The pole figures obtained on specimens deformed in Domains 1 and 3 are strikingly similar, indicating that the operating slip system controls the texture evolution. Compression in Domains 1 and 3 nearly randomizes the intense basal texture in the as-received specimens, while a new texture is generated in Domain 2 with basal poles at 45° to ND or transverse direction (TD). This new texture will promote basal slip when loaded in a transverse direction. When loaded in the normal direction (ND), the processing map exhibited four domains. In Domains 1 and 4, {10 1 ¯ l} <11 2 ¯ 3> slip occurs, while {11 2 ¯ 2} <11 2 ¯ 3> slip occurs in Domains 2 and 3. The pole figures obtained from specimens deformed in Domains 1 and 4 have similar features, while those deformed in Domains 2 and 3 exhibited similar features to one another, confirming that the operating slip systems control the texture development since they are the same in each pair. The compression along ND produces strong basal textures with the basal planes normal to the ED. The texture gets intensified with increased temperature of deformation and causes strong anisotropy in mechanical properties.
The Peculiarities of Convective Heat Transfer in Melt of a Multiple-Electrode Arc Furnace
Authors: Kukharev Alexsey , Bilousov Vyacheslav , Bilousov Ecaterina , Bondarenko Vitaly
Published: October 2019

The modern direction of improving the technology of steel production in high-power arc furnaces is the intensification of magnetohydrodynamic effects for mixing the melt. In this article, a furnace design is proposed that contains three roof arc and three bottom electrodes, which provides the formation of additional eddy currents in the melt when the furnace is supplied with direct current or a low-frequency current. For a numerical study of the features of heat transfer in the melt of this furnace, a three-dimensional mathematical model of magnetohydrodynamic and thermal processes was used. The results were processed using the methods of visualization of vortex structures and the Richardson criterion. In an oven with a capacity of 180 tons at currents in the electrodes of 80 kA, the conditions for the interaction of electric vortex and thermogravitational convection were studied. Results showed that thermogravitational convection due to nonuniform heating of the melt led to a decrease in the size of the main electric vortex flow and the formation of an additional flow near the side walls of the furnace. The features of azimuthal flows formed in the areas of electric arcs and hearth electrodes were analyzed. Results showed that the multivortex structure of the flows that formed in the furnace allowed the volume of stagnant zones to be reduced and provided acceptable melt mixing conditions. The results can be used to improve the energy and structural parameters of three-electrode arc furnaces.
Spreading Process Maps for Powder-Bed Additive Manufacturing Derived from Physics Model-Based Machine Learning
Authors: Desai Prathamesh S. , Higgs C. Fred
Published: October 2019

The powder bed additive manufacturing (AM) process is comprised of two repetitive steps—spreading of powder and selective fusing or binding the spread layer. The spreading step consists of a rolling and sliding spreader which imposes a shear flow and normal stress on an AM powder between itself and an additively manufactured substrate. Improper spreading can result in parts with a rough exterior and porous interior. Thus it is necessary to develop predictive capabilities for this spreading step. A rheometry-calibrated model based on the polydispersed discrete element method (DEM) and validated for single layer spreading was applied to study the relationship between spreader speeds and spread layer properties of an industrial grade Ti-6Al-4V powder. The spread layer properties used to quantify spreadability of the AM powder, i.e., the ease with which an AM powder spreads under a set of load conditions, include mass of powder retained in the sampling region after spreading, spread throughput, roughness of the spread layer and porosity of the spread layer. Since the physics-based DEM simulations are computationally expensive, physics model-based machine learning, in the form of a feed forward, back propagation neural network, was employed to interpolate between the highly nonlinear results obtained by running modest numbers of DEM simulations. The minimum accuracy of the trained neural network was 96%. A spreading process map was generated to concisely present the relationship between spreader speeds and spreadability parameters.
Influence of Drying Method on NMR-Based Metabolic Profiling of Human Cell Lines
Authors: Petrova Irina , Xu Shenyuan , Joesten William C. , Ni Shuisong , Kennedy Michael A.
Published: October 2019

Metabolic profiling of cell line and tissue extracts involves sample processing that includes a drying step prior to re-dissolving the cell or tissue extracts in a buffer for analysis by GC/LC-MS or NMR. Two of the most commonly used drying techniques are centrifugal evaporation under vacuum (SpeedVac) and lyophilization. Here, NMR spectroscopy was used to determine how the metabolic profiles of hydrophilic extracts of three human pancreatic cancer cell lines, MiaPaCa-2, Panc-1 and AsPC-1, were influenced by the choice of drying technique. In each of the three cell lines, 40–50 metabolites were identified as having statistically significant differences in abundance in redissolved extract samples depending on the drying technique used during sample preparation. In addition to these differences, some metabolites were only present in the lyophilized samples, for example, n-methyl-α-aminoisobutyric acid, n-methylnicotimamide, sarcosine and 3-hydroxyisovaleric acid, whereas some metabolites were only present in SpeedVac dried samples, for example, trimethylamine. This research demonstrates that the choice of drying technique used during the preparation of samples of human cell lines or tissue extracts can significantly influence the observed metabolome, making it important to carefully consider the selection of a drying method prior to preparation of such samples for metabolic profiling.
A Driving System for Fast and Precise Gray-Scale Response Based on Amplitude–Frequency Mixed Modulation in TFT Electrowetting Displays
Authors: Yi Zichuan , Liu Linwei , Wang Li , Li Wei , Shui Lingling , Zhou Guofu
Published: October 2019

The gray-scale display which is driven by PWM (pulse width modulation) in TFT (thin film transistor) electrowetting displays (EWDs) has some shortcomings, such as large amplitude of oil oscillation in pixels and slow response speed for displaying gray scale. In this paper, an amplitude–frequency mixed modulation driving system is proposed to improve the response speed of driving gray scale and enhance the oil stability when the gray scale is displayed. In the initial stage of the driving process, the oil is driven by a high voltage to close to the target luminance, and the driving voltage is then decreased to stabilize the oil. The electrowetting hysteresis curve was used to calculate the relation model between the driving voltage and the luminance of the pixel in the system, and the driving voltage value of the pixel at each driving stage was then set to make the oil precisely and rapidly stabilize at the target luminance value. In the output driving platform, the amplitude–frequency mixed modulation is realized based on the source IC, which was used to realize digital-to-analog conversion. An 8 inch EWD was tested using an Admesy colorimeter, and the experimental results show that the pixel response time is reduced by 70% and the gray-scale oscillation is reduced by 80%.
Analysis and Simulation of Forcing the Limits of Thermal Sensing for Microbolometers in CMOS–MEMS Technology
Authors: Göktaş Hasan , Gökhan Fikri Serdar
Published: October 2019

Room-temperature highly sensitive microbolometers are becoming very attractive in infrared (IR) sensing with the increase in demand for the internet of things (IOT), night vision, and medical imaging. Different techniques, such as building extremely small-scale devices (nanotubes, etc.) or using 2D materials, showed promising results in terms of high sensitivity with the cost of challenges in fabrication and low-noise readout circuit. Here, we propose a new and simple technique on the application of joule heating on a clamped–clamped beam without adding any complexity. It provides much better uniformity in temperature distribution in comparison to conventional joule heating, and this results in higher thermal stresses on fixed ends. This consequently brings around 60.5× improvement in the overall temperature sensitivity according to both theory and COMSOL (multiphysics solver). The sensitivity increased with the increase in the stiffness constant, and it was calculated as 134 N/m for a device with a 60.5× improvement. A considerable amount of decrease in the operation temperature (36× below 383 K and 47× below 428 K) was achieved via a new technique. That’s why the proposed solution can be used either to build highly reliable long-term devices or to increase the thermal sensitivity.
Cryptosporidium Prevalence in Calves and Geese Co-Grazing on Four Livestock Farms Surrounding Two Reservoirs Supplying Public Water to Mainland Orkney, Scotland
Authors: Wells Beth , Paton Claire , Bacchetti Ross , Shaw Hannah , Stewart William , Plowman James , Katzer Frank , Innes Elisabeth A
Published: October 2019

The parasite Cryptosporidium parvum represents a threat to livestock health and production, water quality and public health. Cattle are known to be significant reservoirs of C. parvum, but transmission routes are complex and recent studies have implicated the potential role of wildlife in parasite transmission to cattle and water sources. On the Orkney Isles, high densities of Greylag geese (Anser anser) cause widespread faecal contamination of cattle pastures, where cryptosporidiosis is known to be the main cause of neonatal calf diarrhoea and Cryptosporidium contamination frequently occurs in two reservoirs supplying Mainland Orkney’s public water. This study aimed to determine the Cryptosporidium species and subtypes present in geese and calves co-grazing on four farms surrounding two reservoirs on Mainland Orkney. Results indicated a high level of C. parvum prevalence in calves, geese and water samples. gp60 analysis illustrated that higher genotypic diversity was present in the goose population compared with calves, but did not yield sequence results for any of the water samples. It can be concluded that the high levels of C. parvum evident in calves, geese and water samples tested represents a significant risk to water quality and public health.
The Signature Microbiota Drive Rumen Function Shifts in Goat Kids Introduced to Solid Diet Regimes
Authors: Lv Xiaokang , Chai Jianmin , Diao Qiyu , Huang Wenqin , Zhuang Yimin , Zhang Naifeng
Published: October 2019

The feeding regime of early, supplementary solid diet improved rumen development and production in goat kids. However, the signature microbiota responsible for linking dietary regimes to rumen function shifts are still unclear. This work analyzed the rumen microbiome and functions affected by an early solid diet regime using a combination of machine learning algorithms. Volatile fatty acids (i.e., acetate, propionate and butyrate) fermented by microbes were found to increase significantly in the supplementary solid diet groups. Predominant genera were found to alter significantly from unclassified Sphingobacteriaceae (non-supplementary group) to Prevotella (supplementary solid diet groups). Random Forest classification model revealed signature microbiota for solid diet that positively correlated with macronutrient intake, and linearly increased with volatile fatty acid production. Bacteria associated with carbohydrate and protein metabolism were also identified. Utilization of a Fish Taco analysis portrayed a set of intersecting core species contributed to rumen function shifts by the solid diet regime. The core community structures consisted of the specific, signature microbiota and the manipulation of their symbiotic partners are manipulated by extra nutrients from concentrate and/or forage, and then produce more volatile fatty acids to promote rumen development and functions eventually host development. Our study provides mechanisms of the microbiome governed by a solid diet regime early in life, and highlights the signature microbiota involved in animal health and production.
Nanoscale Automated Quantitative Mineralogy: A 200-nm Quantitative Mineralogy Assessment of Fault Gouge Using Mineralogic
Authors: Graham Shaun , Keulen Nynke
Published: October 2019

Effective energy-dispersive X-ray spectroscopy analysis (EDX) with a scanning electron microscope of fine-grained materials (submicrometer scale) is hampered by the interaction volume of the primary electron beam, whose diameter usually is larger than the size of the grains to be analyzed. Therefore, mixed signals of the chemistry of individual grains are expected, and EDX is commonly not applied to such fine-grained material. However, by applying a low primary beam acceleration voltage, combined with a large aperture, and a dedicated mineral classification in the mineral library employed by the Zeiss Mineralogic software platform, mixed signals could be deconvoluted down to a size of 200 nm. In this way, EDX and automated quantitative mineralogy can be applied to investigations of submicrometer-sized grains. It is shown here that reliable quantitative mineralogy and grain size distribution assessment can be made based on an example of fault gouge with a heterogenous mineralogy collected from Ikkattup nunaa Island, southern West Greenland.
Using Reservoir Geology and Petrographic Observations to Improve CO2 Mineralization Estimates: Examples from the Johansen Formation, North Sea, Norway
Authors: Sundal Anja , Hellevang Helge
Published: October 2019

Reservoir characterization specific to CO2 storage is challenging due to the dynamic interplay of physical and chemical trapping mechanisms. The mineralization potential for CO2 in a given siliciclastic sandstone aquifer is controlled by the mineralogy, the total reactive surface areas, and the prevailing reservoir conditions. Grain size, morphologies and mineral assemblages vary according to sedimentary facies and diagenetic imprint. The proposed workflow highlights how the input values for reactive mineral surface areas used in geochemical modelling may be parameterized as part of geological reservoir characterization. The key issue is to separate minerals both with respect to phase chemistry and morphology (i.e., grain size, shape, and occurrence), and focus on main reactants for sensitivity studies and total storage potentials. The Johansen Formation is the main reservoir unit in the new full-value chain CO2 capture and storage (CCS) prospect in Norway, which was licenced for the storage of CO2 as of 2019. The simulations show how reaction potentials vary in different sedimentary facies and for different mineral occurrences. Mineralization potentials are higher in fine-grained facies, where plagioclase and chlorite are the main cation donors for carbonatization. Reactivity decreases with higher relative fractions of ooidal clay and lithic fragments.
New Molecular Insights into the Inhibition of Dipeptidyl Peptidase-4 by Natural Cyclic Peptide Oxytocin
Authors: Chittepu Veera C. S. R. , Kalhotra Poonam , Osorio-Gallardo Tzayhri , Jiménez-Martínez Cristian , Robles-de la Torre Raúl René , Gallardo-Velazquez Tzayhri , Osorio-Revilla Guillermo
Published: October 2019

Protease inhibition has led to treating many diseases and has been successful in producing many commercial drugs by pharmaceutical companies. Among many proteases, serine protease has been attractive in treating metabolic disorder diabetes mellitus (DM). Gliptins have been proven to inhibit dipeptidyl peptidase-4 (DPP4), a serine protease, and are an emerging therapeutic drug target to reduce blood glucose levels, but until now there is no natural cyclic peptide proven to inhibit serine protease DPP4. This study demonstrates the potential mechanism of natural cyclic peptide oxytocin (OXT) as a DPP4 inhibitor. To achieve this, initially, activity atlas and field-based models of DPP4 inhibitors were utilized to predict the possible features of positive and negative electrostatic, hydrophobic, and activity shapes of DPP4 inhibition. Oxytocin binding mode, flexibility, and interacting residues were studied using molecular docking simulations studies. 3D-RISM calculations studies revealed that the stability of water molecules at the binding site are favorable. Finally, an experimental study using fluorescence assay revealed OXT inhibits DPP4 in a concentration-dependent manner in a significant way (p < 0.05) and possess IC50 of 110.7 nM. These new findings significantly expand the pharmaceutical application of cyclic peptides, and in specific OXT, and implicate further optimization of OXT inhibition capacity to understand the effect of DPP4 inhibition. This work highlights the development of natural cyclic peptides as future therapeutic peptides to reduce glucose levels and treat diabetes mellitus.
Photon-Induced Superior Antibacterial Activity of Palladium-Decorated, Magnetically Separable Fe3O4/Pd/mpg-C3N4 Nanocomposites
Authors: Thakur Deepika , Ta Qui Thanh Hoai , Noh Jin-Seo
Published: October 2019

Three-component nanocomposites (Fe3O4/Pd/mpg-C3N4) have been systematically synthesized using a three-step solution method for the photocatalytic bacterial decontamination. The mesoporous g-C3N4 nanosheets (mpg-C3N4), which were prepared by the acid treatment, showed a great improvement in photocatalytic performance. The photoluminescence intensity of the mpg-C3N4 nanosheets was disclosed to drop about 60% from the value of normal g-C3N4 nanosheets. Decoration of mpg-C3N4 with palladium (Pd) nanoparticles led to the effective suppression of carrier recombination and the carrier migration to Fe3O4 nanoparticles. It was revealed that the three-component nanocomposites degraded 99.9% of E. coli and 99.8% of S. aureus bacterial strains within 2 h of solar light irradiation at a 100 μg/mL concentration, demonstrating their superb photocatalytic antibacterial activity. In addition, the nanocomposites could be easily separated from the bacterial cells and repeatedly used for photocatalytic bacterial degradation with good recyclability. The strong photon-induced antibacterial activity and good recyclability of the three-component nanocomposites may represent their potential as a promising antibacterial photocatalyst.
Genistein as Potential Therapeutic Candidate for Menopausal Symptoms and Other Related Diseases
Authors: Thangavel Prakash , Puga-Olguín Abraham , Rodríguez-Landa Juan F. , Zepeda Rossana C.
Published: October 2019

Plant-derived compounds have recently attracted greater interest in the field of new therapeutic agent development. These compounds have been widely screened for their pharmacological effects. Polyphenols, such as soy-derived isoflavones, also called phytoestrogens, have been extensively studied due to their ability to inhibit carcinogenesis. These compounds are chemically similar to 17β-estradiol, and mimic the binding of estrogens to its receptors, exerting estrogenic effects in target organs. Genistein is an isoflavone derived from soy-rich products and accounts for about 60% of total isoflavones found in soybeans. Genistein has been reported to exhibit several biological effects, such as anti-tumor activity (inhibition of cell proliferation, regulation of the cell cycle, induction of apoptosis), improvement of glucose metabolism, impairment of angiogenesis in both hormone-related and hormone-unrelated cancer cells, reduction of peri-menopausal and postmenopausal hot flashes, and modulation of antioxidant effects. Additionally, epidemiological and clinical studies have reported health benefits of genistein in many chronic diseases, such as cardiovascular disease, diabetes, and osteoporosis, and aid in the amelioration of typical menopausal symptoms, such as anxiety and depression. Although the biological effects are promising, certain limitations, such as low bioavailability, biological estrogenic activity, and effects on target organs, have limited the clinical applications of genistein to some extent. Moreover, studies report that modification of its molecular structure may eliminate the biological estrogenic activity and its effects on target organs. In this review, we summarize the potential benefits of genistein on menopause symptoms and menopause-related diseases like cardiovascular, osteoporosis, obesity, diabetes, anxiety, depression, and breast cancer.