255 research outputs found

    A new method for identifying micro fractures and characterizing fractures of different scales

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    Oil and gas exploration professionals have begun to focus more on unconventional oil and gas reserves in recent years as a result of their increased efforts. Fractures have a significant impact on the permeability and connectivity of reservoirs as a crucial component of rock mechanics and hydraulics, which directly affects the production of oil and gas. The identification of fracture development zones or micro faults, as well as how to adequately define the fracturing model, have thus become crucial and pressing issues in the forecast of oil and gas reservoirs. In this study, we decompose the three-dimensional seismic data volume in a site in order to obtain the single frequency data volume that can be calculated using the ant tracking technique. We do this by taking advantage of the synchronous extrusion improvement of short time Fourier transform in time-frequency focusing. Coupled with the advanced DFN model, the extracted data are calibrated in various rock attributes to restore the morphology and characteristics of fractures. The findings demonstrate that this method is capable of providing not only a precise outline of micro fractures but also a reflection of the characteristics of fractures at various scales, including structure and associated properties. The precision and applicability of this method are confirmed in this paper, which is significant as a reference for the oil and gas exploration industry

    The SNP rs961253 in 20p12.3 Is Associated with Colorectal Cancer Risk: A Case-Control Study and a Meta-Analysis of the Published Literature

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    Background: Colorectal cancer (CRC) is the third common cancer and the fourth leading cause of cancer death worldwide. A single nucleotide polymorphism (SNP), rs961253 located in 20p12, was firstly described to be associated with the increased risk of CRC in a genome-wide association study; however, more recent replication studies yielded controversial results. Methodology/Principal Findings: A hospital-based case-control study in a Chinese population was firstly performed, and then a meta-analysis combining the current and previously published studies were conducted to explore the real effect of rs961253 in CRC susceptibility. In the Chinese population including 641 cases and 1037 controls, per-A-allele conferred an OR of 1.60 (95 % CI = 1.26–2.02) under additive model. In the meta-analysis including 29859 cases and 29696 controls, per-Aallele have an OR of 1.13 (95 % CI = 1.09–1.18) under a random-effects model due to heterogeneity (P = 0.019). Nevertheless, the heterogeneity can be totally explained by ethnicity, with the tau 2 reduced to 0 after including ethnicity in metaregression model. In stratified analysis by ethnicity, per-A-allele had ORs of 1.34 (95 % CI = 1.20–1.50) and 1.11 (95% CI = 1.08–1.14) for Asian and European, respectively, without heterogeneity. Modest influence of each study was observed on overall estimate in sensitive analysis, and evident tendency to significant association was seen in cumulative analysis over time, together indicating the robust stability of the current results

    Influencing factors of medication literacy among community-dwelling older adult patients with hypertension: a study based on social learning theory

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    Objective: This study aimed to examine the factors affecting medication literacy in community-dwelling older adults with hypertension, guided by social learning theory. It sought to analyze the pathways these factors influenced and provide a theoretical foundation for designing targeted intervention programs.Study design: This is a cross-sectional study.Methods: From October 2022 to February 2023, a total of 432 community-dwelling older adults with hypertension from Linghe District, Guta District, and Taihe District, Jinzhou City, Liaoning Province, China, were selected using convenience sampling. Data were collected using a socio-demographic questionnaire, a medication literacy questionnaire, the Brief Illness Perception Questionnaire, the General Self-efficacy Scale, and the Perceived Social Support Scale. The collected data were analyzed with Kruskal-Wallis and Mann-Whitney tests, correlation analysis, multiple stepwise regression analysis, and structural equation modeling (SEM).Results: The medication literacy score among the participants was 3.83 ± 1.91. Multi-factor analysis revealed key factors affecting their medication literacy, including blood pressure-control status, utilization of community health education resources, receiving guidance for medication usage, marital status, number of annual visits, social support, self-efficacy, and disease perception. The SEM based on social learning theory showed that general self-efficacy mediated the relationship between social support, disease perception, and medication literacy.Conclusion: The present study developed a model and provided potential intervention strategies to improve medication literacy, knowledge, and safety among community-dwelling older adults with hypertension, considering the relationships between the identified variables

    Deletions in CWH43 cause idiopathic normal pressure hydrocephalus

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    Idiopathic normal pressure hydrocephalus (iNPH) is a neurological disorder that occurs in about 1% of individuals over age 60 and is characterized by enlarged cerebral ventricles, gait difficulty, incontinence, and cognitive decline. The cause and pathophysiology of iNPH are largely unknown. We performed whole exome sequencing of DNA obtained from 53 unrelated iNPH patients. Two recurrent heterozygous loss of function deletions in CWH43 were observed in 15% of iNPH patients and were significantly enriched 6.6-fold and 2.7-fold, respectively, when compared to the general population. Cwh43 modifies the lipid anchor of glycosylphosphatidylinositol-anchored proteins. Mice heterozygous for CWH43 deletion appeared grossly normal but displayed hydrocephalus, gait and balance abnormalities, decreased numbers of ependymal cilia, and decreased localization of glycosylphosphatidylinositol-anchored proteins to the apical surfaces of choroid plexus and ependymal cells. Our findings provide novel mechanistic insights into the origins of iNPH and demonstrate that it represents a distinct disease entity

    Topology hierarchy of transition metal dichalcogenides built from quantum spin Hall layers

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    The evolution of the physical properties of two-dimensional material from monolayer limit to the bulk reveals unique consequences from dimension confinement and provides a distinct tuning knob for applications. Monolayer 1T'-phase transition metal dichalcogenides (1T'-TMDs) with ubiquitous quantum spin Hall (QSH) states are ideal two-dimensional building blocks of various three-dimensional topological phases. However, the stacking geometry was previously limited to the bulk 1T'-WTe2 type. Here, we introduce the novel 2M-TMDs consisting of translationally stacked 1T'-monolayers as promising material platforms with tunable inverted bandgaps and interlayer coupling. By performing advanced polarization-dependent angle-resolved photoemission spectroscopy as well as first-principles calculations on the electronic structure of 2M-TMDs, we revealed a topology hierarchy: 2M-WSe2, MoS2, and MoSe2 are weak topological insulators (WTIs), whereas 2M-WS2 is a strong topological insulator (STI). Further demonstration of topological phase transitions by tunning interlayer distance indicates that band inversion amplitude and interlayer coupling jointly determine different topological states in 2M-TMDs. We propose that 2M-TMDs are parent compounds of various exotic phases including topological superconductors and promise great application potentials in quantum electronics due to their flexibility in patterning with two-dimensional materials

    Transient Pulmonary Atelectasis after Ketamine Sedation during Cardiac Catheterization in Spontaneously Breathing Children with Congenital Heart Disease

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    Background: Ketamine is applied widely for sedation during cardiac catheterization in spontaneously breathing children with congenital heart disease (CHD). However, a rare and unreported respiratory complication, transient and reversible atelectasis of lungs (TRAL), was identified. Purpose: The study was performed to investigate retrospectively the prevalence and clinical characteristics of TRAL after ketamine sedation in pediatric cardiac catheterization. Methods: Four thousand four hundred and seventy-four sick children were sedated with ketamine, and pediatric cardiac catheterization was carried out under spontaneous breathing. TRAL was detected in 33 children (17 M/16 F, age was 2.1±1.7 years) by retrospective analysis. The clinical and radiographic characteristics were recorded before, during and after TRAL. Results: In pediatric cardiac catheterization, the prevalence of TRAL was 0.74% after ketamine sedation. TRAL occurred in 23 children with cyanotic CHD, and 10 with acyanotic CHD. All TRALs had common clinical and radiographic features: the diffuse opacity of bilateral lungs developed rapidly (identified under X-ray fluoroscopy), associated with decrease in lung volume, and then the decrease in SpO2 (94.2±9.2% vs. 59.4±2.2%, P<0.05), and heart rates (143.5±14.3 bpm vs. 58.3±9.7 bpm, P<0.05) followed quickly. TRAL was relieved by supportive oxygen in 32 children (23 with face mask, and 9 with endotracheal intubation), and the duration of TRAL was 1.6±0.5 minutes. However, TRAL caused the death of one child. Conclusions: TRAL is a rare and urgent respiratory complication after ketamine sedation, and the mechanism is unclear. Rapid and diffuse opacity of bilateral lungs is the earliest sign of TRAL in pediatric cardiac catheterization, and the immediate supportive oxygen is crucial

    Observation of topological electronic structure in quasi-1D superconductor TaSe3

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    Topological superconductors (TSCs), with the capability to host Majorana bound states that can lead to non-Abelian statistics and application in quantum computation, have been one of the most intensively studied topics in condensed matter physics recently. Up to date, only a few compounds have been proposed as candidates of intrinsic TSCs, such as doped topological insulator CuxBi2Se3 and iron-based superconductor FeTe0.55Se0.45. Here, by carrying out synchrotron and laser based angle-resolved photoemission spectroscopy (ARPES), we systematically investigated the electronic structure of a quasi-1D superconductor TaSe3, and identified the nontrivial topological surface states. In addition, our scanning tunneling microscopy (STM) study revealed a clean cleaved surface with a persistent superconducting gap, proving it suitable for further investigation of potential Majorana modes. These results prove TaSe3 as a stoichiometric TSC candidate that is stable and exfoliable, therefore a great platform for the study of rich novel phenomena and application potentials.Comment: to appear in Matte
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