bluuebunny/crossref_metadata_2025 huggingface dataset:
On relative ranks of the semigroup of orientation-preserving transformations on infinite chains
Authors: Dimitrova Ilinka , Koppitz Jörg
Published: November 2020

In this paper, we determine the relative rank of the semigroup [Formula: see text] of all orientation-preserving transformations on infinite chains modulo the semigroup [Formula: see text] of all order-preserving transformations.
Total coloring of quasi-line graphs and inflated graphs
Authors: Mohan S. , Geetha J. , Somasundaram K.
Published: November 2020

A total coloring of a graph is an assignment of colors to all the elements (vertices and edges) of the graph such that no two adjacent or incident elements receive the same color. A claw-free graph is a graph that does not have [Formula: see text] as an induced subgraph. Quasi-line and inflated graphs are two well-known classes of claw-free graphs. In this paper, we prove that the quasi-line and inflated graphs are totally colorable. In particular, we prove the tight bound of the total chromatic number of some classes of quasi-line graphs and inflated graphs.
Computing Protein pKas Using the TABI Poisson–Boltzmann Solver
Authors: Chen Jiahui , Hu Jingzhen , Xu Yongjia , Krasny Robert , Geng Weihua
Published: November 2020

A common approach to computing protein pKas uses a continuum dielectric model in which the protein is a low dielectric medium with embedded atomic point charges, the solvent is a high dielectric medium with a Boltzmann distribution of ionic charges, and the pKa is related to the electrostatic free energy which is obtained by solving the Poisson–Boltzmann equation. Starting from the model pKa for a titrating residue, the method obtains the intrinsic pKa and then computes the protonation probability for a given pH including site–site interactions. This approach assumes that acid dissociation does not affect protein conformation aside from adding or deleting charges at titratable sites. In this work, we demonstrate our treecode-accelerated boundary integral (TABI) solver for the relevant electrostatic calculations. The pKa computing procedure is enclosed in a convenient Python wrapper which is publicly available at the corresponding author’s website. Predicted results are compared with experimental pKas for several proteins. Among ongoing efforts to improve protein pKa calculations, the advantage of TABI is that it reduces the numerical errors in the electrostatic calculations so that attention can be focused on modeling assumptions.
The prebiotic fiber inulin ameliorates cardiac, adipose tissue, and hepatic pathology, but exacerbates hypertriglyceridemia in rats with metabolic syndrome
Authors: Komatsu Yuki , Aoyama Kiyoshi , Yoneda Mamoru , Ashikawa Sao , Nakano Shiho , Kawai Yumeno , Cui Xixi , Furukawa Nozomi , Ikeda Katsuhide , Nagata Kohzo
Published: November 2020

Prebiotics ameliorate dysbiosis and influence metabolism and the immune system, but their effects on cardiovascular complications in metabolic disorders remain largely unknown. Inulin ameliorated hypertension, cardiac injury, and diastolic dysfunction without affecting obesity or insulin resistance in a rat model of metabolic syndrome. The favorable cardiac effects of inulin may be related to inhibition of systemic inflammation associated with a reduction in circulating interleukin-6 levels. Additionally, inulin exacerbated hypertriglyceridemia but alleviates adipose tissue and hepatic pathology in these animals, as well as increased the number of regulatory T cells in adipose tissue.
Diagnostic Value of Soluble Form of Mer Tyrosine Kinase (sMerTK) in Tuberculous Pleural Effusion and Malignant Pleural Effusion
Authors: Liu Han , Wang Shuai , Zhang Zhenzhen , Jie Jing , Song Lei , Hua Shucheng
Published: November 2020

Objectives. With the development of proteomics, it has been indicated that differentially expressed proteins are biological markers for the diagnosis of different types of pleural effusion (PE). The aim of our study was to explore the value of sMerTK (soluble form of Mer tyrosine kinase) in the differential diagnosis of tuberculous pleural effusion (TPE) and malignant pleural effusion (MPE). In addition, we also wanted to explore whether MerTK was associated with IL‐1β and TNF‐α, which are inflammatory factors related to pleural effusion. Methods. We screened all patients who underwent thoracoscopy and had a definite diagnosis. In total, 136 patients were enrolled in this study and classified into two groups, with 64 patients in the TPE group and 72 patients in the MPE group. The concentrations of sMerTK in the TPE and MPE groups were detected by ELISA. The diagnostic accuracy was determined by generating receiver operating characteristic (ROC) curves and calculating the area under the curve (AUC). Correlations between the expression level of sMerTK and those of the inflammatory factors interleukin 1 beta (IL‐1β) and tumor necrosis factor alpha (TNF‐α) were also studied using Pearson’s linear correlation analysis. Results. The concentrations of sMerTK were 5,278.77 ± 2,479.98 ng/L and 859.91 ± 540.45 ng/L in the TPE and MPE groups, respectively. The concentration of sMerTK in TPE was shown to be significantly higher than that in MPE (P < 0.05). The area under the ROC curve for sMerTK in distinguishing TPE from MPE was 0.958, with a cutoff value of 2,122 ng/L. The sensitivity and specificity for sMerTK were 98.61% and 90.63% (P < 0.05). The expression levels of sMerTK in these two groups were not correlated with those of the inflammatory factors IL‐1β and TNF‐α (P > 0.05). Conclusions. The expression level of sMerTK in PE could be a potential biomarker for common use in the diagnosis of TPE and MPE.
The Generation and Regulation of Tissue-Resident Tregs and Their Role in Autoimmune Diseases
Authors: Wang Shuang , Zou Xueyang , Zhang Yi , Wang Xiaoya , Yang Wei , Li Yi
Published: November 2020

Regulatory T cells (Tregs), as an important subset of T cells, play an important role in maintaining body homeostasis by regulating immune responses and preventing autoimmune diseases. In-depth research finds that Tregs have strong instability and plasticity, and according to their developmental origin, Tregs can be classified into thymic-derived Tregs (tTregs), endogenous-induced Tregs (pTregs), which are produced by antigen-stimulated T cells in the periphery in vivo, and induced Tregs (iTregs), which differentiate from naïve T cells in vitro. In recent years, studies have found that Tregs are divided into lymphatic and tissue-resident Tregs according to their location. Research on the generation and function of lymphoid Tregs has been more comprehensive and thorough, but the role of tissue Tregs is still in the exploratory stage, and it has become a research hot spot. In this review, we discuss the instability and plasticity of Tregs and the latest developments of tissue-resident Tregs in the field of biology, including adipose tissue, colon, skeletal muscle, and other Tregs that have been recently discovered as well as their production, regulation, and function in specific tissues and their role in the pathogenesis of autoimmune diseases.
Evaluation of the Antibacterial Activity and Probiotic Potential of Lactobacillus plantarum Isolated from Chinese Homemade Pickles
Authors: Zeng Y. , Li Y. , Wu Q. P. , Zhang J. M. , Xie X. Q. , Ding Y. , Cai S. Z. , Ye Q. H. , Chen M. T. , Xue L. , Wu S. , Zeng H. Y. , Yang X. J. , Wang J.
Published: November 2020

This study investigated the antipathogenic activity and probiotic potential of indigenous lactic acid bacteria (LAB) isolated from Chinese homemade pickles. In total, 27 samples were collected from different sites in China. Fifty-nine yielded pure colonies were identified by 16S rRNA gene sequencing as LAB and were initially evaluated for the antibacterial activity in vitro. Initial screening yielded Lactobacillus plantarum GS083, GS086, and GS090, which showed a broad-spectrum antibacterial activity against food-borne pathogens, especially multidrug-resistant pathogens. Meanwhile, organic acids were mainly responsible for the antimicrobial activity of the LAB strains, and the most abundant of these was lactic acid (19.32 ± 0.95 to 24.79 ± 0.40 g/l). Additionally, three L. plantarum strains demonstrated several basic probiotic characteristics including cell surface hydrophobicity, autoaggregation, and survival under gastrointestinal (GI) tract conditions. The safety of these isolates was also evaluated based on their antibiotic susceptibility, hemolytic risk, bile salt hydrolase activity, and existence of virulence or antibiotic resistance genes. All strains were safe at both the genomic and phenotypic levels. Therefore, L. plantarum GS083, GS086, and GS090 are fairly promising probiotic candidates and may be favorable for use as preservatives in the food industry.
An Enhanced Differential Evolution Algorithm with Fast Evaluating Strategies for TWT-NFSP with SSTs and RTs
Authors: Hu Rong , Wu Xing , Qian Bin , Mao Jian L. , Jin Huai P.
Published: November 2020

The no-wait flow-shop scheduling problem with sequence-dependent setup times and release times (i.e., the NFSP with SSTs and RTs) is a typical NP-hard problem. This paper proposes an enhanced differential evolution algorithm with several fast evaluating strategies, namely, DE_FES, to minimize the total weighted tardiness objective (TWT) for the NFSP with SSTs and RTs. In the proposed DE_FES, the DE-based search is adopted to perform global search for obtaining the promising regions or solutions in solution space, and a fast local search combined with three presented strategies is designed to execute exploitation from these obtained regions. Test results and comparisons with two effective meta-heuristics show the effectiveness and robustness of DE_FES.
Software Defect Prediction Based on Fuzzy Weighted Extreme Learning Machine with Relative Density Information
Authors: Zheng Shang , Gai Jinjing , Yu Hualong , Zou Haitao , Gao Shang
Published: November 2020

To identify software modules that are more likely to be defective, machine learning has been used to construct software defect prediction (SDP) models. However, several previous works have found that the imbalanced nature of software defective data can decrease the model performance. In this paper, we discussed the issue of how to improve imbalanced data distribution in the context of SDP, which can benefit software defect prediction with the aim of finding better methods. Firstly, a relative density was introduced to reflect the significance of each instance within its class, which is irrelevant to the scale of data distribution in feature space; hence, it can be more robust than the absolute distance information. Secondly, a K-nearest-neighbors-based probability density estimation (KNN-PDE) alike strategy was utilised to calculate the relative density of each training instance. Furthermore, the fuzzy memberships of sample were designed based on relative density in order to eliminate classification error coming from noise and outlier samples. Finally, two algorithms were proposed to train software defect prediction models based on the weighted extreme learning machine. This paper compared the proposed algorithms with traditional SDP methods on the benchmark data sets. It was proved that the proposed methods have much better overall performance in terms of the measures including G-mean, AUC, and Balance. The proposed algorithms are more robust and adaptive for SDP data distribution types and can more accurately estimate the significance of each instance and assign the identical total fuzzy coefficients for two different classes without considering the impact of data scale.
Exploitation of Hybrid Vigor for Identification of Promising Sorghum F1 Hybrid for High Grain Yield and Resistance to Sorghum Midge
Authors: Hamidou Massaoudou , Souleymane Oumarou , Salifou Mahamadou , Ba Malick N. , Kapran Issoufou , Gracen Vernon , Ofori Kwado , Yirenkyi Danquah Eric
Published: November 2020

Sorghum is the second most grown cereal crop in Niger. However, sorghum production in the country is dominated by indigenous cultivars with low productivity. Productivity in grain sorghum has been achieved in developing countries around the world using hybrids. This study was conducted to evaluate heterosis in F1 sorghum hybrids for grain yield and resistance to midge. Fifty F1 sorghum hybrids were evaluated for grain yield and resistance to midge. Variation for grain yield, midge resistance, and flowering time was observed. The magnitude of better parent heterosis for grain yield and resistance to midge varied significantly among hybrids. Four hybrids combined high better parent heterosis for both grain yield and resistance to midge while eight hybrids were better than their better parent for resistance to midge. These hybrids performed well for grain yield and/or resistance to midge. Therefore, the parental lines involved in these hybrids can be advanced for commercial hybrids production or used in sorghum improvement programs.
The Role of Oxidative Stress in Early Brain Injury after Subarachnoid Hemorrhage
Authors: Jelinek M. , Jurajda M. , Duris K.
Published: November 2020

This review focuses on the problem of oxidative stress in early brain injury (EBI) after spontaneous subarachnoid hemorrhage (SAH). EBI involves complex pathophysiological mechanisms, including oxidative stress. In the first section, we describe the main sources of free radicals in EBI. There are several sources of excessive generation of free radicals from mitochondrial free radicals’ generation and endoplasmic reticulum stress, to hemoglobin and enzymatic free radicals’ generation. The second part focuses on the disruption of antioxidant mechanisms in EBI. The third section describes some newly found molecular mechanisms and pathway involved in oxidative stress after EBI. The last section is dedicated to the pathophysiological mechanisms through which free radicals mediate early brain injury.
Pregnancy in an Asymptomatic Woman with Porencephalic and Arachnoid Cysts
Authors: Pepe Franco , Marchese Gianmarco , Pepe Gabriele Giuseppe , Zambrotta Elisabetta , Insalaco Giulio , Garraffo Claudia , La Rosa Valeria
Published: November 2020

A 25-year-old woman presented to the obstetric clinic in her first pregnancy. The patient was accompanied by her mother who reported an episode of intracerebral hemorrhage after birth and also remembered access to the emergency department after generalized tonic-clonic seizure as an infant. She was not able to describe the therapy for seizure preventions and even when and why it was suspended, but she affirmed that no residual neurological consequences were detected in the following years. Actually, the pregnant woman was in good health without neurological symptoms nor assumed any therapy. A neurologist reviewed the patient’s CT scan in which arachnoid cyst and porencephalic cyst were evident, and he assessed that no abnormalities were found in motor, sensory, and mental state examination. EEG did not show any epileptiform or seizure-like activity. No antiepileptic drug was prescribed due to the absence of symptoms since many years. The patient had no neurological symptoms during pregnancy or obstetric complications and delivered at term a healthy baby through a caesarean section. She breastfed, and after two years, the patient and the baby are healthy. The association of porencephalic and arachnoid cyst in pregnancy is an extremely rare neurological condition that needs a multidisciplinary counseling in pregnancy, but an uneventful course is possible.
Clinical Relevance of Anti-TNF Antibody Trough Levels and Anti-Drug Antibodies in Treating Inflammatory Bowel Disease Patients
Authors: Reinhold Ilana , Blümel Sena , Schreiner Jens , Boyman Onur , Bögeholz Jan , Cheetham Marcus , Rogler Gerhard , Biedermann Luc , Scharl Michael
Published: November 2020

Background and Aims: The majority of patients treated with anti-tumor necrosis factor (TNF) therapy develop anti-drug antibodies (ADAs), which might result in loss of treatment efficacy. Strict guidelines on measuring trough levels (TLs) and ADA in clinical routine do not exist. To provide real-world data, we took advantage of our tertiary inflammatory bowel disease (IBD) center patient cohort and determined indicators for therapeutic drug monitoring (TDM) and actual consequences in patient care. Methods: We retrospectively collected clinical data of 104 IBD patients treated with infliximab or adalimumab in our IBD clinic. Patients with TL and ADA measurements between June 2015 and February 2018 were included. Results: The main reason for determining TL was increased clinical disease. Subtherapeutic TLs were found in 33 patients, therapeutic TLs in 33 patients, and supratherapeutic TLs in 38 patients. Adjustments in anti-TNF therapy occurred more frequently (p = 0.01) in patients with subtherapeutic TL (24 of 33 patients; 73%) as compared to patients with therapeutic and supratherapeutic TLs (26 of 71 patients; 37%). No correlation could be found between TL and disease activity (p = 0.16). Presence of ADA was found in 16 patients, correlated with the development of infusion reactions (OR: 10.6, RR: 5.4, CI: 2.9–38.6), and was associated with subtherapeutic TL in 15 patients (93.8%). Treatment adaptations were based on TL and/or ADA presence in 36 of 63 patients. Conclusions: TDM showed significant treatment adaptations in patients with subtherapeutic TL. Conversely, in patients with therapeutic and supratherapeutic TLs, reasons for adaptations were based on considerations other than TL, such as clinical disease activity. Further studies should focus on decision-making in patients presenting with supratherapeutic TL in remission.
Iron Measured in Nasal Exudate Samples as a New and Useful Biomarker in the Differential Diagnosis of Patients with Acute Stroke
Authors: García-Cabo Carmen , Llano-Suárez Pablo , Benavente Fernández Lorena , Costa-Fernández Jose Manuel , Fernández-Abedul Maria Teresa , Calleja-Puerta Sergio
Published: November 2020

Introduction: Differential diagnosis between ischemic and hemorrhagic strokes in the acute stage is one of the major challenges of neurovascular research. Several biomarkers have been studied, but attempts to date have focused on determining their blood levels. Recently, cerebral lymphatic drainage toward the nostrils has been discovered, giving us the chance to study nasal exudate looking for biomarkers of neural damage. We sought to confirm whether iron levels in nasal exudate could identify the hemorrhagic nature of acute stroke. Methods: We studied iron nasal exudate levels in 32 ischemic and 43 hemorrhagic stroke patients. All patients underwent neurological examination assessed by the National Institutes of Health Stroke Scale (NIHSS), brain computed tomography to the differential diagnosis of stroke subtype, laboratory tests, and measurement of iron levels in nasal exudate. Results: The iron levels in nasal exudate were higher in hemorrhagic stroke patients. The area under the receiver operating characteristic curve for ischemic/hemorrhagic stroke discrimination was 0.896 (95% confidence interval 0.823–0.970) and cutoff point of 0.078 nmol/mg (sensitivity 93%, specificity 73%). Conclusions: Our findings suggest that iron levels in nasal exudate may be useful in the acute stage for the differential diagnosis between ischemic and hemorrhagic damage in acute stroke patients. They also open a potential field to study other biomarkers in nasal exudate in several neurological disorders. Clinical studies must be performed to confirm our results.
Clinicopathological Analysis of Medullary Ray Injury in 1-Year Protocol Paediatric Renal Allograft Biopsies
Authors: Hashimoto Junya , Oguchi Hideyo , Mikami Tetuo , Hamasaki Yuko , Muramatsu Masaki , Yamaguchi Yutaka , Sakai Ken
Published: November 2020

Aim: Medullary ray injury was recently reported in renal transplant biopsies. This study was performed to clarify the clinicopathological features of medullary ray injury in paediatric living renal transplant recipients. Methods: Paediatric recipients who completed a 5-year follow-up after living renal transplantation were enroled. We evaluated the clinical and pathological parameters of the presence or absence of medullary ray injury in their 1-year protocol biopsies. Results: Of 48 1-year protocol biopsies, 18 (37.5%) showed histological evidence of medullary ray injury. The 48 paediatric recipients were classified as those with medullary ray injury (n = 18; MRI-1Y [+] group) and those without medullary ray injury (n = 30; MRI-1Y [−] group) in the 1-year protocol biopsies. The prevalence of histological evidence of calcineurin inhibitor (CNI) nephrotoxicity, chronic obstruction or reflux nephropathy, and imaging findings of vesicoureteral reflux was 66.7, 22.2, and 7.7% in the MRI-1Y (+) group and 33.3, 13.3, and 15.4% in the MRI-1Y (−) group, respectively. Only the prevalence of CNI nephrotoxicity was significantly different between the 2 groups. There was no significant difference in the mean estimated glomerular filtration rate at 1, 3, or 5 years after transplantation between the 2 groups. Conclusion: In total, 37.5% of 1-year protocol biopsies showed histological evidence of medullary ray injury. This finding suggests that CNI nephrotoxicity might be the main contributor to medullary ray injury in 1-year protocol biopsies. The presence of medullary ray injury had little influence on renal function, at least during the first 5 years after transplantation.
2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy: Executive Summary
Authors:   Writing Committee Members, Ommen Steve R. , Mital Seema , Burke Michael A. , Day Sharlene M. , Deswal Anita , Elliott Perry , Evanovich Lauren L. , Hung Judy , Joglar José A. , Kantor Paul , Kimmelstiel Carey , Kittleson Michelle , Link Mark S. , Maron Martin S. , Martinez Matthew W. , Miyake Christina Y. , Schaff Hartzell V. , Semsarian Christopher , Sorajja Paul
Published: November 2020

Aim

This executive summary of the hypertrophic cardiomyopathy clinical practice guideline provides recommendations and algorithms for clinicians to diagnose and manage hypertrophic cardiomyopathy in adult and pediatric patients as well as supporting documentation to encourage their use.

Methods

A comprehensive literature search was conducted from January 1, 2010, to April 30, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, Agency for Healthcare Research and Quality reports, and other relevant databases.

Structure

Many recommendations from the earlier hypertrophic cardiomyopathy guidelines have been updated with new evidence or a better understanding of earlier evidence. This summary operationalizes the recommendations from the full guideline and presents a combination of diagnostic work-up, genetic and family screening, risk stratification approaches, lifestyle modifications, surgical and catheter interventions, and medications that constitute components of guideline directed medical therapy. For both guideline-directed medical therapy and other recommended drug treatment regimens, the reader is advised to follow dosing, contraindications and drug-drug interactions based on product insert materials.
Understanding the Scope of the Institutional Transformation within the Microfinance Sector: Evidence from Sidian Bank in Kenya
Authors: Biringanine Alexis Nyamugira
Published: November 2020

This article investigates the impact of the change in the legal status of a microfinance institution on its social and financial performance. It uses a case study with a strong emphasis on both quantitative and qualitative approaches to understand the stakeholders’ perceived value of transformation. The results from the study reveal that transformation significantly improves the profitability and the efficiency of Sidian Bank, and in addition, improves the quality of its portfolio. However, we found that transformation has altered significantly the social objectives of Sidian Bank by decreasing its breadth and depth of social outreach. Insights from the qualitative approach reveal that the average loan size widely used to proxy mission drift is a biased indicator since clients grow over time and always favor bigger loans. The stakeholders’ perceived value of transformation differs in terms of risks, breadth, and financial results.
Conducting Non-COVID-19 Clinical Trials during the Pandemic: Can Today’s Learning Impact Framework Efficiency?
Authors: Lalova Teodora , Negrouk Anastassia , Deleersnijder Angelique , Valcke Peggy , Huys Isabelle
Published: November 2020

The COVID-19 pandemic has severely disrupted non-coronavirus clinical trials. In the case of life-threatening diseases, such as cancer, this is particularly dangerous, as treatment cannot simply be stopped. In the EU, guidelines for the management of ongoing studies were issued; however, national coordination is still lacking. This article aims to raise awareness on the struggle of managing ongoing clinical trials in the EU during the pandemic. The goals are to bring attention, from a legal and regulatory point of view to the difficulties faced by those involved in clinical research, and to critically position the current hurdles against the backdrop of the existing legal and ethical framework. We investigated the EU guidance and the national approaches of all EU/EEA Member States, and critically discussed selected issues. We argue that the crisis may be an opportunity to foresee meaningful changes in the EU clinical trials framework post-COVID-19.
Populist Mediation of the Pandemic
Authors: Marker Silas
Published: November 2020

The potential impact of right-wing populist media on society is a matter of growing importance. This paper examines the discourse of the three Danish right-wing populist media Den Korte Avis, NewsSpeek and 24Nyt during the corona crisis in 2020. Using the post-structuralist theoretical framework and discursive approach to populism of Ernesto Laclau, it finds that despite some differences, all three of them articulate Muslim immigrants as a particular problem demanding particular attention in the corona crisis; they accuse the so-called mainstream media of lying or keeping secrets about the crisis, thereby positioning themselves as mediums of the truth; and they accuse the international institutions of lying and utilizing the corona crisis for their own globalist aims.
Biopolitical Populism in Poland: The Case of PiS
Authors: Yatsyk Alexandra
Published: November 2020

This paper examines the discourse of PiS party in Poland as a form of biopolitical populism. I view this phenomenon as a specific style of political discourse rather than an ideology, that, first, focuses on bodily issues, including family and gender policy, sexual behavior, etc., second—it is inherently performative and as such it appeals to emotions, and, third—it directly communicates with “people” while circumventing the existing institutional framework of the state. Based on the cases of PiS rhetoric on the Smolensk catastrophe, and its narratives on gender and anti-LGBTQ issues, I demonstrate how the latter could be used for political othering and for subverting the core democratic principles. My data includes publications in Polish media and on social platforms (Twitter and Facebook), mostly before and after elections to European and national parliaments in May and October 2019, as well as during the presidential election in spring 2020.
Analysis of the Submicrostructural Deformation of Amphibole in a Ductile Shear Zone Based on the TEM Technique
Authors: Zhang Xiaoli , He Jinxian , Ren Zeqiang , Zhou Taotao , Cao Wenjie , Xu Ben
Published: November 2020

Deformed amphibole in the plagioclase amphibolite mylonite of the Guandi Complex, Xishan, Beijing, is the research object in this study. The amphibole nanodeformation under the middle crust was analyzed using microstructural analysis and high-resolution transmission electron microscopy
(TEM). Microscope observations show that the amphibolite deformations in the plagioclase amphibolite mylonite are δ and σ type porphyroclasts, and the porphyroclast tail is composed of new long-columnar crystals. Using transmission electron microscopy (TEM, and this acronyms would
be defined only once), the authors observed the nanodeformation characteristics of the amphibole porphyroclast core and mantle. Dislocation tangles are dominant in the porphyroclast core, and inside the new crystal, there is little or no dislocation. Swelled new crystals surrounded by dislocation
can be observed in the transition zone between the porphyroclasts and new crystals. The deformed amphibole microstructure and submicrostructure represent typical brittle–ductile transitional deformation. The deformation process can be divided into two stages: the disordered dislocation
increment stage and the dislocation reduction and ordering stage. Crystalline plastic deformation occurs in the amphibole in the plagioclase amphibolite mylonite of the Xishan area, Beijing. The crystalline plastic deformation temperature in amphiboles is higher than that in plagioclase.
Effect of Temperature and Pressure on Nanoscale Pores in Closed Coal
Authors: He Jun , Wang Mingke , Pan Jienan , Wang Xianglong , Tang Yiju
Published: November 2020

To understand the nanoscale pore development characteristics of closed coal under the combined influence of temperature and confined pressure, a series of experiments at different temperatures and pressures were carried out using a custom closed coal temperature and pressure experimental system. The lean coal samples were taken from a mining area in Qinshui Basin, North China. In these experiments, the temperature was 200 °C or 300 °C, the pressure was 14 MPa or 23 MPa, respectively, and the experiment duration was 12 h. The CH4/N2/CO2isothermal adsorption tests were carried out on all samples. The results show that the custom experimental system can be used to effectively study the effect of mechanical-thermal interaction on the nanoscale pores in closed coal. Before and after the experiment, the Langmuir volume increases, and the methane adsorption capacity increases. The specific surface area and pore volume of the micropores (<1 nm) decrease, but the specific surface area and pore volume of the pores (6–100 nm) increase. The specific surface area and pore volume of the micropores (<1 nm) are negatively correlated with the temperature and decrease with increasing temperature. Fractal analysis results show that under the influence of temperature and pressure, the heterogeneity of the nanoscale pore structure and the roughness of the pore surface increase. This research is of important theoretical significance for the safe mining of deep coal seams and for the development of coalbed methane resources.
Control Mechanism of the Effective Stress on Nano-Micro Pores and the Permeability of High-Rank Coals
Authors: Ji Xiaofeng , Song Dangyu , Yu Shaokai , He Kaikai , Li Yunbo
Published: November 2020

To study the change and main control factors of the high-rank coal reservoir permeability in deep coal seams, permeability tests under different stresses and gas pressures were carried out in the laboratory. The development and distribution of nano-micro pores and fractures in the coal
matrix were analyzed and observed by mercury intrusion porosimetry, gas adsorption, scanning electron microscope and computed tomography to reveal the permeability variation mechanism. The results showed that the initial permeability of the coal samples ranged from 0.0114 mD to 0.2349 mD when
the effective stress was 0 MPa, and it clearly varied among different samples. The permeability of all the coal samples was very sensitive to the effective stress and decreased exponentially with the increase of the effective stress. The increase of the pore pressure also led to a decrease
of the permeability, whereas the impact of the pore pressure on permeability was less obvious compared with the effective stress. Sub-nanopores, nanopores, micro-fractures and larger fractures are all developed in the coal samples. Connected larger fractures were the main gas migration channels
in permeability determination, and the narrowing, disconnection, and closure of the fractures caused by the increase of the effective stress were the most important reasons for significant reduction of permeability.
Micro-Nano Fine Characterization of Coal Fracture Evolution During the Triaxial Compression Creep
Authors: Lu Weidong , Wei Guoying , Wang Zehua , Jia Tianrang , Sun Shaodong , Ju Yiwen
Published: November 2020

The production and evolution of fractures during coal creep will directly affect the occurrence, extraction and flow law of gas in a coal seam. The coal fracture evolution under creep conditions was studied by qualitative analysis and quantitative characterization. At a room temperature
of 24 °C, triaxial compression creep tests of coal samples from the Zhaogu No. 2 coal mine in Jiaozuo were carried out under different loading conditions (0 MPa, 6 MPa, 9 MPa and 12 MPa), and low field nuclear magnetic resonance technique tests and industrial CT scanning experiments were
performed. The obtained CT images were analyzed with the MATLAB software for equalization and binary image processing. The development and distribution of fractures in coal samples under different loading conditions were studied. The results show that the internal fractures are unevenly distributed
and controlled by the main fracture, and the expansion direction of fractures is parallel to the direction of the maximum effective compressive stress. The number of fractures shows an increasing trend with the increase of axial stress, and the pace of growth of new fractures accelerates.
The primary fractures in the coal body expand and generate new fractures, which improves the connectivity of the fractures in the coal body. The research results can provide a basis for studying the gas flow rule around the borehole and determining the influence range of the borehole.
Study of the Influence of Biodegradation on Coal Micro-Nano Pore Structure Using Low-Temperature N2 Adsorption
Authors: Kang Hongli , Liu Xiangrong , Yang Zaiwen , Zhao Shunsheng , Yang Zheng
Published: November 2020

An experimental study of biodegradation of Shenmu coal was carried out by using Ochrobactrum cytisi, Novospingobium naphthalenivorans, Alcaligenes faecalis and Pseudomonas fluorescens. The micro-nano pore structure of coal samples before and after biodegradation was studied
by low-temperature N2 adsorption. For biodegraded coal, the results showed that micropores and mesopores are primarily open pores with good connectivity, including parallel plate pores and cylinder pores with two open ends; the specific surface area of biodegraded coal decreased
from 2.2174 m2/g to 1.6255˜2.0537 m2/g, and the pore size of the coal biodegraded by the four bacteria decreased following biodegradation from 250 nm to 170˜200 nm, which may be due to collapse of the coal structure due to the bacterial degradation. Coal biodegradation
by the dominant bacterium P. fluorescens led to a diminished mesopore size and an increased number of smaller mesopores, with the smaller mesopores gradually taking on dominant roles.
Prevention of Nanoscale Fines in Open-Hole Horizontal Coalbed Methane Wells During the Drainage Process
Authors: Guo Chunhua , Yang Yu , Sun Hansen , Chen Wangang , Yan Ping , Wu Xiang , Zhang Hao
Published: November 2020

Because coal is quite weak compared with conventional sandstone, shear failure downhole will produce a large amount of nanoscale coal fines during the drainage process. Since the size of pores in coal is on the nanoscale range, these fines will sometimes cause serious damage problems
downhole. The origin of coal fines cannot be explained by conventional sand prediction theory, which was previously designed for conventional sandstone. During the drainage process, the in situ stress change in coal was caused by the combination of the poroelastic effect, methane desorption
and compression around the borehole. To prevent nanoscale coal fines, the critical pressure drawdown can be predicted by the comprehensive stress model. A special test was also designed to determine the key model parameters, making the model easy to use. It was proven that the induced stress
due to methane desorption can exaggerate the shear failure, which is different from conventional sand prediction theory. Based on the stress model, the safe window of bottom hole pressure was applied for open-hole horizontal wells to prevent the origin of nanoscale coal fines.
Micro/Nanopore Systems in Lacustrine Tight Oil Reservoirs, China
Authors: Li Qiyan , Wu Songtao , Zhai Xiufen , Pan Songqi , Lin Senhu
Published: November 2020

A nanoscale pore throat system develops extensively in rocks of unconventional reservoirs serving as both source and reservoir rock. The nanoscale pores provide the main storage spaces, accounting for 70% to 80% of the total unconventional tight reservoirs in China. As one of most important
unconventional petroleum accumulations, tight oil has accumulated in more than 20 lacustrine strata since the Permian in China. Three types of tight oil reservoirs were identified based on the lithology and provenance in the lacustrine basins, including terrigenous sandstone, endogenous carbonate
rocks and mixed sedimentary rocks. The micro/nanopore structures of these tight rocks were investigated with the application of optical microscopy, scanning electron microscopy (SEM), mercury injection capillary pressure (MICP), gas adsorption (GA) and nuclear magnetic resonance (NMR). The
results indicated that the pore systems were connected by nanoscale throats dominated the storage spaces of the lacustrine tight oil reservoirs, while there were obvious differences among these three tight rocks, including pore types, pore size and movable fluid distribution. (i) The terrigenous
sandstones, which were represented by the Triassic Chang 7 tight sandstones in the Ordos Basin and Cretaceous Quantou tight sandstones in the Songliao Basin, were mainly arkoses, and their storage space was mainly composed of dissolution pores and intraclay mineral pores. Feldspar, rock fragments
and carbonate cements were the majority of the dissolved components, and the diameter of dissolution pores ranged from 1 micron to 50 microns. Abundant intrakaolinite and illite/smectite mixed layers pores were developed, and the pore size was 10 nm to 500 nm. The MICP and GA data suggested
that storage spaces were connected by throats with diameters of 10 nm˜300 nm. (ii) The endogenous carbonate rocks, which were represented by the Jurassic Da’anzhai limestones in the Sichuan Basin, were the tightest rocks with porosities of less than 5% and permeabilities of less
than 0.01×10−3 μm2. The calcite dissolution pores and fractures with diameters of 10 nm˜500 nm were the most important storage spaces. The majority of pore systems were connected by throats with diameters of 6 nm˜100 nm based on the MICP and
GA data. (iii) The tight mixed sedimentary rocks, which were represented by the Permian Lucaogou Formation in the Junggar Basin, were complex in lithologic composition, and dolostones and dolomite sandstones were the most important exploration targets. The interdolomite pores were the dominant
storage spaces, in which abundant illite/smectite mixed layers were filled, and the pore size ranged from 50 nm to 50 microns. The MICP and GA data showed that the storage space was dominated by throats with diameters of 10 nm˜200 nm, and their volumetric contributions could reach over
70%. These results could provide a reference for future tight oil research and exploration in China.
Micro-Nanostructure of Coal and Adsorption-Diffusion Characteristics of Methane
Authors: Jia Tianrang , Liu Cao , Wei Guoying , Yan Jiangwei , Zhang Qinghao , Niu Lifei , Liu Xiaolei , Zhang Mingjie , Ju Yiwen , Zhang Yongjun
Published: November 2020

The adsorption and diffusion characteristics of coal are important parameters for coalbed methane (CBM) extraction and mine gas control. However, the adsorption test can only obtain the apparent adsorption amount, and it cannot obtain the actual adsorption amount, which leads to a large
error during the calculation of the coal diffusion coefficient. Taking the anthracite coal in the Jiulishan Mine as the research object, the micro-nanostructure and instantaneous apparent methane adsorption isotherms of the primary structure coal and tectonic coal were determined by low-temperature
CO2 adsorption, mercury intrusion and methane diffusion kinetics tests, and the instantaneous apparent adsorption isotherms of methane were corrected to the instantaneous actual adsorption isotherm by the Langmuir model. The results demonstrate that the micro-nanopore, Density Function
Theory (DFT) pore volume and specific surface area values below 1–2 nm in tectonic coal are larger than those in the primary structure coal, which is the fundamental reason why the ultimate adsorption capacity of tectonic coal is larger than that of the primary structure coal. The apparent
adsorption amounts of the tectonic coal and the primary structure coal reach the maximum at 8 MPa and 10 MPa, respectively. Thereafter, the instantaneous isotherms of the apparent adsorption amount decrease with increasing of gas pressure. However, the instantaneous isotherms of the actual
adsorption amount tend to be stable. The diffusion coefficient undergoes a rapid decay with time under low gas pressure, and undergoes a slow decay with under the high gas pressure.
Neighbourhood deprivation, life satisfaction and earnings: Comparative analyses of neighbourhood effects at bespoke scales
Authors: Knies Gundi , Melo Patricia C , Zhang Min
Published: November 2020

Neighbourhood socioeconomic disadvantage has a profound impact on individuals’ earnings and life satisfaction. Since definitions of the neighbourhood and research designs vary greatly across studies, it is difficult to ascertain which neighbourhoods and outcomes matter the most. By conducting parallel analyses of the impact of neighbourhood deprivation on life satisfaction and earnings at multiple scales, we provide a direct empirical test of which scale matters the most and whether the effects vary between outcomes. Our identification strategy combines rich longitudinal information on individual characteristics, family background and initial job conditions for England and Wales with econometric estimators that address residential sorting bias, and we compare results for individuals living in choice-restricted social housing with results for those living in self-selected privately rented housing. We find that the effect of neighbourhood deprivation on life satisfaction and wages is negative for both outcomes and largely explained by strong residential sorting on both individual and neighbourhood characteristics rather than a genuine causal effect. We also find that the results overall do not vary by neighbourhood scale.
Effects of Check-In Check-Out on Engagement of Students Demonstrating Internalizing Behaviors in an Elementary School Setting
Authors: Kladis Kristin , Hawken Leanne S. , O’Neill Robert E. , Fischer Aaron J. , Fuoco Kristen Stokes , O’Keeffe Breda V. , Kiuhara Sharlene A.
Published: November 2020

Check-In Check-Out (CICO) is an evidence-based Tier 2 intervention that has most often been used to support students who exhibit externalizing problem behaviors; however, emerging research suggests that CICO may be effective when extended to students who are engaging in internalizing problem behaviors (CICO-IB). The purpose of this study was to replicate previous research using CICO to support students with internalizing behaviors as well as to extend the research using a standardized Daily Progress Report (DPR) for all students. A multiple baseline design across students was used to examine the effects of CICO-IB on social and academic engagement with four elementary students from an urban U.S. elementary school who were exhibiting internalizing behavior problems (e.g., shyness, social withdrawal). Results indicated that CICO-IB was effective in improving active academic and social engagement for all four students included in the study as measured by both teacher rating on a DPR and direct observation. Overall, the majority of teachers, parents, and students found the intervention socially acceptable. Implications for future research and practice with students who are at risk or exhibiting emotional/behavioral disorders along with limitations are discussed.
Numerical investigation of Von Karman swirling bioconvective nanofluid transport from a rotating disk in a porous medium with Stefan blowing and anisotropic slip effects
Authors: Bég O Anwar , Kabir Muhammad Nomani , Uddin Md Jashim , Izani Md Ismail Ahmad , Alginahi Yasser M
Published: November 2020

In recent years, significant progress has been made in modern micro- and nanotechnologies for micro/nano-electronic devices. These technologies are increasingly utilizing sophisticated fluid media to enhance performance. Among the new trends is the simultaneous adoption of nanofluids and biological micro-organisms. Motivated by bio-nanofluid rotating disk oxygenators in medical engineering, in the current work, a mathematical model is developed for steady convective von-Karman swirling flow from an impermeable radially stretched disk rotating in a Darcy porous medium saturated with nanofluid doped with gyrotactic micro-organisms. Anisotropic slip at the wall and blowing effects due to concentration are incorporated. The nano-bio transport model is formulated using nonlinear partial differential equations, which are transformed to a set of similarity ordinary differential equations (SODEs) by appropriate transformations. The transformed boundary value problem is solved by a Chebyshev spectral collocation method (CSCM). Impacts of key parameters on dimensionless velocity components, concentration, temperature and motile microorganism density distributions are investigated and graphically visualized. Validation with previous studies is included. It is found that that the effects of suction provide a better enhancement of the heat, mass and microorganisms transfer in comparison to blowing. Moreover, physical quantities decrease with higher slip parameters irrespective of the existence of blowing. Temperature is suppressed with increasing thermal slip, while nanoparticle concentration is suppressed with increasing wall mass slip. Micro-organism density number increases with the greater microorganism slip. Radial skin friction is boosted with positive values of the power law stretching parameter, whereas it is decreased with negative values. The converse response is computed for circumferential skin friction, nanoparticle mass transfer rate and motile micro-organism density number gradient. Results from this study are relevant to novel bioreactors, membrane oxygenators, food processing and bio-chromatography.
Water management and wheat yields in ancient China: Carbon isotope discrimination of archaeological wheat grains
Authors: Xinying Zhou , Lin Zhu , Spengler Robert N , Keliang Zhao , Junchi Liu , Xing Xu , Yige Bao , Dodson John , Hai Xu , Xiaoqiang Li
Published: November 2020

The evaluation of ancient crop production and its response to climate change is key to exploring the ancient demographic and social changes. Wheat is currently the third most widely cultivated crop worldwide and was a major component across of the agricultural systems of the ancient Eurasia. In this study, the Δ13C values of 116 charred wheat grains from 28 archaeological sites, with direct AMS 14C dating of 3952 ± 66 to 389 ± 73 cal yr BP, across northern China are reported. The result shows that the Δ13C values estimated wheat yields ranged from 0.5 to 2.5 Mg ha−1, during the past 4000 years. The water supply and grain yield of wheat cultivation is the highest in China during the Bronze Age; however, the water supply and yield were significantly affected by climate fluctuation in the middle-late Holocene. No significant long-term trend of increasing wheat yield is observed over this interval, but a correlation between Δ13C values estimated wheat yield and cyclical climate changes can be noted.