bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on the permeability characteristics of coal containing coalbed methane under different loading paths
Authors: Wang Fakai , He Jiangfu , Liang Yunpei , Luo Yongjiang , Liao Zhiwei , Li Lei 
Published: July 2018

AbstractDuring the degassing process of coalbed methane, the external loads could change the permeability of the coal seam by means of transient and permanent deformations, which dramatically influence the production efficiency of coalbed gas. Due to the ignorance of irreversible deformation of coal permeability, the gas extraction efficiency and the prediction of gas disaster in underlying mining need to be improved. Thus, it is better to clarify the permeability change characteristics with irreversible deformation of coal. In this paper, the influence of different loading paths on the permeability of gas‐containing coal was studied, and six loading paths were studied by employing a self‐designed triaxial cyclic loading system. The results of this study show that the permeability of gas‐containing coal samples would significantly change with different loading paths. Corresponding to the variation of mining pressure or periodic geo‐stress varying in the excavation of roadways, both an increase in the axial pressure and an increase in the confining pressure would cause a decrease in gas permeability. In addition, the permeability of gas‐containing coal would be damaged even when the external loads are removed. When given a constant strain loading, the permeability shows a “V”‐shaped change with increased strain, and the transversal point of permeability locates between the yield point and the peak intensity. Therefore, it can be concluded that external loads less than the maximum strength of coal would lead to permeability loss in the coal seam, vice versa, the permeability will be increased. Hence, research results contributes to improving the gas permeability and increasing the gas production from coalbed by imposing effective loads on original coal seams through mining speed control.
The chemical degradation of the oil sludge produced from polymer flooding in offshore oilfield
Authors: Chen Bin , Zhao Lin , Duan Ming , Yao Meng , Fang Shenwen , Wang Chengsheng , Chen Shijia 
Published: July 2018

AbstractUsually, the treatment of oil sludge produced from polymer flooding (OSPPF) in offshore oilfield needs transport and incineration. It is time‐consuming and high‐economic cost. In this paper, firstly, the OSPPF in an offshore oilfield was analyzed by IR, SEM, EDS, and XRD and its formation mechanism was discussed. Then, chemical degradation was proposed according to the formation mechanism. Mixture of H2O2 and diethylene triamine pentacetic acid (DTPA) was chosen for the chemical degradation of OSPPF. The effects of different factors on degradation rate were studied and the national condition was obtained as follows: 3 g OSPPF, 3 g kerosene, and 9 g aqueous solutions containing 5 wt% H2O2+ DTPA (H2O2:DTPA was 1:1) were mixed at 65°C for 12 hour. After the degradation, the oil in the OSPPF can be recovered and polymer gel in the OSPPF can be destroyed completely. This chemical degradation is a good choice for treatment of OSPPF in situ.
Physical and chemical characterization of natural and modified nanoclays and their ecotoxicity on a freshwater algae species (Chlamydomonas reinhardtii)
Authors: Tullio Suelen C.M.C. , Barbosa Ronilson V. , Chalcraft David R. 
Published: July 2018

Abstract

Nanoclays represent a class of natural and modified nanomaterials that have received attention from industrial and environmental fields. Studies that assess the physicochemical properties of nanoclays and compare the effects of natural and modified nanoclays are scarce. We assessed the physicochemical characteristics of a natural nanoclay (Na+ montmorillonite) and 2 modified nanoclays (Cloisite® 30B and Novaclay™) in the dry powder state and in solution, and their potential toxic effects on algal population growth (Chlamydomonas reinhardtii). All 3 nanoclays exhibited properties that are thought to cause toxic effects on organisms, but the properties varied among the nanoclays. Cloisite 30B had a low particle stability and a chemical composition that are thought to induce a greater toxic effect on organisms than either Novaclay or natural nanoclay. In contrast, Novaclay and natural nanoclay had a particle shape (nanoplate) in solution that is thought to induce a greater toxic effect on organisms than the type of particle shape (spherical) that Cloisite 30B has in solution. Cloisite 30B suppressed population growth of C. reinhardtii, an effect that increased with dosage. Neither Novaclay nor natural nanoclay affected algal population growth across a broad array of concentrations. The results show that modified nanoclays differ in their impact on algae, and careful thought must be given to their usage because some will have negative consequences if released into aquatic ecosystems. Environ Toxicol Chem 2018;37:2860–2870. © 2018 SETAC
Abstract
Cloisite 30B®, but not Novaclay™ or natural nanoclay, suppresses algal population growth.
Large-effect mutations generate trade-off between predatory and locomotor ability during arms race coevolution with deadly prey
Authors: Hague Michael T. J. , Toledo Gabriela , Geffeney Shana L. , Hanifin Charles T. , Brodie Edmund D. , Brodie Edmund D. 
Published: July 2018

AbstractAdaptive evolution in response to one selective challenge may disrupt other important aspects of performance. Such evolutionary trade-offs are predicted to arise in the process of local adaptation, but it is unclear if these phenotypic compromises result from the antagonistic effects of simple amino acid substitutions. We tested for trade-offs associated with beneficial mutations that confer tetrodotoxin (TTX) resistance in the voltage-gated sodium channel (NaV1.4) in skeletal muscle of the common garter snake (Thamnophis sirtalis). Separate lineages in California and the Pacific Northwest independently evolved TTX-resistant changes to the pore of NaV1.4 as a result of arms race coevolution with toxic prey, newts of the genus Taricha. Snakes from the California lineage that were homozygous for an allele known to confer large increases in toxin resistance (NaV1.4LVNV) had significantly reduced crawl speed compared to individuals with the ancestral TTX-sensitive channel. Heterologous expression of native snake NaV1.4 proteins demonstrated that the same NaV1.4LVNV allele confers a dramatic increase in TTX resistance and a correlated decrease in overall channel excitability. Our results suggest the same mutations that accumulate during arms race coevolution and beneficially interfere with toxin-binding also cause changes in electrophysiological function of the channel that may affect organismal performance. This trade-off was only evident in the predator lineage where coevolution has led to the most extreme resistance phenotype, determined by four critical amino acid substitutions. If these biophysical changes also translate to a fitness cost—for example, through the inability of T. sirtalis to quickly escape predators—then pleiotropy at this single locus could contribute to observed variation in levels of TTX resistance across the mosaic landscape of coevolution.
Groundwater flow and storage processes in an inactive rock glacier
Authors: Harrington Jordan S. , Mozil Alexandra , Hayashi Masaki , Bentley Laurence R. 
Published: July 2018

AbstractGroundwater flow through coarse blocky landforms contributes to streamflow in mountain watersheds, yet its role in the alpine hydrologic cycle has received relatively little attention. This study examines the internal structure and hydrogeological characteristics of an inactive rock glacier in the Canadian Rockies using geophysical imaging techniques, analysis of the discharge hydrograph of the spring draining the rock glacier, and chemical and stable isotopic compositions of source waters. The results show that the coarse blocky sediments forming the rock glacier allow the rapid infiltration of snowmelt and rain water to an unconfined aquifer above the bedrock surface. The water flowing through the aquifer is eventually routed via an internal channel parallel to the front of the rock glacier to a spring, which provides baseflow to a headwater stream designated as a critical habitat for an at‐risk cold‐water fish species. Discharge from the rock glacier spring contributes up to 50% of basin streamflow during summer baseflow periods and up to 100% of basin streamflow over winter, despite draining less than 20% of the watershed area. The rock glacier contains patches of ground ice even though it may have been inactive for thousands of years, suggesting the resiliency of the ground thermal regime under a warming climate.
Bank‐level and country‐level determinants of bank capital structure and funding sources
Authors: Hoque Hafiz , Pour Eilnaz Kashefi 
Published: July 2018

AbstractWe examine the determinants of capital structure and funding sources of 347 large global banks between 1998 and 2016 from 57 countries around the world. We find that the capital structure of banks does not evolve only as a result of capital regulations, it is also affected by market forces. We find that bank capital structure corresponds to corporate finance theory and buffer view and, in particular, that market‐to‐book ratio, size, and risk are positively related and that profitability is negatively related to bank leverage. Banks in countries with higher tax advantages, creditor rights, deposit insurance, and bankruptcy codes have more leverage, and those bound by common law have less leverage. Size and country‐level factors are important determinants of sources of financing.
Nonfinancial sector debt and the U.S. Great Moderation: Evidence from flow‐of‐funds data
Authors: Grydaki Maria , Bezemer Dirk 
Published: July 2018

AbstractIn the mid‐1980s, two shifts occurred in the US economy: the strong decline of macroeconomic volatility and the strong increase of borrowing by the nonfinancial sector above the level of output growth until 2007. Since access to credit may decrease output fluctuations, we hypothesize that during the Great Moderation borrowing by the nonfinancial sector in excess of gross domestic product (GDP) growth moderated GDP fluctuations. We estimate Generalized Autoregressive Conditional Heteroskedasticity (GARCH) models over 1954–2008 to measure output growth volatility and run Vector Autoregressive (VAR) models and a counterfactual simulation in order to analyse the relation of credit growth in excess of output growth and output growth volatility.
The duty to make abortion law transparent: A Malawi case study
Authors: Kangaude Godfrey Dalitso , Mhango Chisale 
Published: July 2018

AbstractDespite adopting a progressive legal and policy framework informed by internationally recognized human rights norms and values, Malawi has not complied with the obligation to explain its abortion law in accordance with legal and human rights standards. In 1930, the colonial government adopted a Penal Code derived from English criminal law, containing provisions regulating access to abortion, but has not undertaken measures to explain when abortion is lawful. What constitutes legal abortion has never been clarified for health providers and potential clients. Consequently, eligible girls and women fail to access safe and legal abortion. The Malawi Law Commission, following its review of the colonial abortion law, has proposed liberal changes which, if implemented, would expand access to safe abortion. However, the immediate step the government ought to take is to clarify the current abortion law, and not to wait for a new law expected to materialize in the indeterminate future.
Colloidal gelatin microgels with tunable elasticity support the viability and differentiation of mesenchymal stem cells under pro‐inflammatory conditions
Authors: Sung Baeckkyoung , Krieger Jess , Yu Bing , Kim Min‐Ho 
Published: July 2018

AbstractDespite a promising potential for mesenchymal stem cells (MSCs) in tissue regeneration, a major challenge in MSC‐based therapy has been associated with poor cell survival and low levels of cell integration into host tissue following transplantation. The objective of this study was to develop a gelatin‐based colloidal microgel platform that enables the encapsulation of viable MSCs as well as confer fine‐tuning of mechanical stiffness and low cytotoxicity. In this study, we report a facile method of fabricating gelatin‐based microgel spheres for the encapsulation of MSCs using a water‐in‐oil mini‐emulsification method, which is covalently crosslinked by genipin. At a given seeding cell number, there was a positive correlation between the size of the microsphere and the number of encapsulated MSCs. Controlling the crosslinking degree of gelatin matrix enabled a fine‐tuning of mechanical stiffness of gel microsphere. MSCs within softer microgel exhibit more spread morphology than the cells in the stiffer matrix, while cells within stiffer matrix become more elongated morphology. Importantly, we show that the colloidal gelatin microgel could support the viability and differentiation of encapsulated MSCs in a pro‐inflammatory environment. This study demonstrates the feasibility of using genipin‐crosslinked gelatin gel microspheres as an injectable carrier of MSCs for tissue engineering applications, which can be further explored for MSC‐based cell therapy for tissue repair. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2753–2761, 2018.
Critical role of endoplasmic reticulum stress in chronic endothelial activation−induced visual deficits in tie2‐tumor necrosis factor mice
Authors: Lenin Raji , Nagy Peter G. , Alli Shanta , Rao Vidhya R. , Clauss Matthias A. , Kompella Uday B. , Gangaraju Rajashekhar 
Published: July 2018

AbstractDiabetic retinopathy (DR) is the leading cause of vision loss among working‐age adults. The interplay between hyperglycemia and endothelial activation in inducing endoplasmic reticulum (ER) stress pathways and visual deficits in DR is not fully understood. To address this, we used a mouse model of chronic vascular activation using endothelial‐specific tumor necrosis factor‐α (TNF‐α)‐expressing (tie2‐TNF) mice to induce diabetes with streptozotocin. At 4 weeks post streptozotocin, a significant 2‐fold to 10‐fold increase in retinal neurovascular inflammatory gene transcript response in tie2‐TNF mice was further increased in diabetic tie2‐TNF mice. A decrease in visual acuity and scotopic b‐wave amplitude in tie2‐TNF mice was further accentuated in diabetic tie2‐TNF mice and these changes correlated with a multi‐fold increase in retinal ER stress markers and a reduction in adherens junctions. Cultured retinal endothelial cells showed a significant decrease in trans‐endothelial resistance as well as VE‐cadherin expression under TNF‐α and high glucose stress. These changes were partly rescued by tauroursodeoxycholic acid, a potent ER stress inhibitor. Taken together, constant endothelial activation induced by TNF‐α further exacerbated by hyperglycemia results in activation of ER stress and chronic proinflammation in a feed forward loop ultimately resulting in endothelial junction protein alterations leading to visual deficits in the retina. Inhibition of ER stress and endothelial activation may prove to be a novel therapeutic target in DR.
Assessment of food quality and microbial safety of brown macroalgae (Alaria esculenta and Saccharina latissima)
Authors: Blikra Marthe J , Løvdal Trond , Vaka Mette R , Roiha Irja S , Lunestad Bjørn Tore , Lindseth Cecilie , Skipnes Dagbjørn 
Published: July 2018

ABSTRACTBackgroundThere has been a rapid increase in the number of seaweed farms in the Western world, and it is crucial for these companies and their customers to have standardized methods for quality assessment and optimization. The aim of this study was to adapt known methods for food‐quality determination for the analysis of seaweed quality, including color, texture, and microbiology, and to discuss optimal heat treatments for the popular macroalgae Saccharina latissima and Alaria esculenta.ResultsThe development of an attractive, green color during heating was highly specific to species, freezing history, and part of the thallus. Resilience and thermostability were also species dependent. Low microbial numbers (1–3 log cfu/g) for total aerobic count, psychrotrophic bacteria, and spore‐forming bacteria were found, but Bacillus spp. were isolated. No enterococci, coliforms, pathogenic vibrios, or Listeria monocytogenes were detected.ConclusionThe methods employed were able to describe clearly the physical and microbial qualities of A. esculenta and S. latissima, and quality changes during processing. Based on the results, optimal cooking for a minimum of 15 min at 95 °C was suggested for S. latissima. Fresh and frozen A. esculenta showed the greenest color after heating for 5–9 s at a high temperature (> 85 °C). If a higher heat load is needed to achieve safe and stable food products, using fresh and not frozen A. esculenta is highly recommended, as fresh specimens remain green even after 15 min at 95 °C. © 2018 Society of Chemical Industry
In‐capillary derivatization with fluorescamine for the rapid determination of adamantane drugs by capillary electrophoresis with UV detection
Authors: Prapatpong Pornpan , Nuchtavorn Nantana , Macka Mirek , Suntornsuk Leena 
Published: July 2018

AbstractIn‐capillary derivatization using fluorescamine as the labeling reagent was proposed to enhance the detectability of adamantine drugs (memantine, amantadine and rimantadine) by spectrophotometric detection. Fluorescamine and the drugs were delivered to the capillary electrophoresis instrument at a ratio of 10:1 by zone injection. The derivatization reaction occurred following the application of voltage (20 kV). The derivatized products, hydrolyzed‐ fluorescamine and excess fluorescamine were separated in 7 min using 100 mM borate buffer (pH 10.0) containing 0.1% w/v of Brij®‐35 and 20% v/v of acetonitrile. Validation data showed good linearity (r2 > 0.98), precision (%RSDs < 3.4), and accuracy (recoveries ranging from 98.0 to 102.0%). The detection and quantitation limits are in the range of 6.0–8.5 and 18–25 μM, respectively. The validation data is comparable to reported methods, however, the current method offers better precision with enhanced sensitivity (up to six times). Applications of the method show percent labeled amounts found in the studied samples within 100.6–109.3%, which complied with the United States Pharmacopeia limit (90.0–110.0%). The method was simple, rapid and, automated, which required no extra instrumentation or skillful operators.
Active microbiome structure and its association with environmental factors and viruses at different aquatic sites of a high‐altitude wetland
Authors: Eissler Yoanna , Gálvez María‐Jesús , Dorador Cristina , Hengst Martha , Molina Verónica 
Published: July 2018

AbstractSalar de Huasco is a high‐altitude wetland characterized by a highly diverse microbial life adapted to extreme climatic and environmental conditions. Our study aims to determine active microbial community structure changes within different aquatic sites and its relationship with environmental factors and viruses as potential drivers of diversification in different aquatic areas of this ecosystem. In this study, bacteria and archaea composition (16S rRNA subunit pyrolibraries) and picoplankton and viral abundance were determined at ponds, springs and lagoon sites of the wetland during wet and dry seasons (February and July 2012, respectively). In general, mixosaline waters (1,400–51,000 μS/cm) usually found in ponds and lagoon presented higher picoplanktonic abundances compared to freshwater (<800 μS/cm) spring sites, ranging from 1.07 × 105 to 1.83 × 107 cells/ml. Viral abundance and viral to picoplankton ratio (VPR) also presented greater values at ponds compared to spring sites, reaching up to 4.78 × 108 viruses‐like particles and up to 351 for VPR. In general, ponds hold a higher microbial diversity and complexity associated also with the presence of microbial mats compared with water sources or lagoon (Shannon index H′ 2.6–3.9 vs. <2.0). A greater richness of archaea was also detected in ponds characterized by functional groups such as known methanogens and ammonia oxidizers, and uncultured groups. In total, our results indicate that among the different aquatic sites of the wetland, ponds presented a great microbial community diversification associated to a higher top‐down control by viruses which may influence nutrient and greenhouse gases cycling.
High temperature accelerates growth of aerobic anoxygenic phototrophic bacteria in seawater
Authors: Sato‐Takabe Yuki , Hamasaki Koji , Suzuki Satoru 
Published: July 2018

AbstractTemperature is an important controlling factor in the growth activity of all microorganisms. Aerobic anoxygenic phototrophic (AAP) bacteria actively grow in the ocean and are known as one of the main driving forces in organic matter cycling in surface seawater environments. Whether temperature change affects AAP bacteria activity from an ecological viewpoint remains an open question. To date, no known studies have reported the effect of temperature change on AAP bacteria growth in the ocean. We here show that the growth rate of AAP bacteria exceeded that of other bacterial types at high water temperatures in the absence of grazers. The slope of the regression line of the net growth rate of AAP bacteria as a function of water temperature was the same as that for non‐AAP bacteria at all temperatures (10, 20, and 30°C); however, when grazers were eliminated, it was 4.7 times higher than that of non‐AAP bacteria. This result suggests that AAP bacteria are more responsive to water temperature increases than other bacteria and that AAP bacteria might become more dominant than other bacteria under elevated water temperatures.
ADCK3‐related Coenzyme Q10 Deficiency: A Potentially Treatable Genetic Disease
Authors: Chang Anna , Ruiz‐Lopez Marta , Slow Elizabeth , Tarnopolsky Mark , Lang Anthony E. , Munhoz Renato P 
Published: July 2018

AbstractBackgroundDisorders related to dysfunction of coenzyme (CoQ10) metabolism, including AarF domain containing kinase 3 gene (ADCK3) mutations, have received attention due to the potential for response to CoQ10 supplementation.MethodsWe describe two new cases of neurological syndromes due to ADCK3 mutations that obtained striking benefit from CoQ10, and a third who did not. We also review 20 cases from the literature in which responses to CoQ10 were documented out of all 38 previously reported cases.ResultsDespite the remarkable responses in some cases with ataxia and movement disorders (myoclonus, dystonia, tremor), overall, we were not able to identify variables that predicted response to CoQ10 supplementation.ConclusionsBased on our experience and data from the literature, we recommend a minimum of 10 mg/kg/day of ubiquinone with titration up to 15 mg/kg/day, maintained at least for 6 months in order to obtain or exclude potential benefit from therapy.