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Preparation and Characterization of Multilayered High-density Polyethylene with Tunable Crystalline Structure
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作者 Yi-Jie Ma Jia-Wei Gong +4 位作者 Bin Chen Ying Zhang Gan-Ji Zhong Zhong-Ming Li Xue-Qin Gao 《Chinese Journal of Polymer Science》 2025年第9期1616-1628,I0011,共14页
In rotationally extruded fittings,high-density polyethylene(HDPE)pipes prepared using conventional processing methods often suffer from poor pressure resistance and low toughness.This study introduces an innovative ro... In rotationally extruded fittings,high-density polyethylene(HDPE)pipes prepared using conventional processing methods often suffer from poor pressure resistance and low toughness.This study introduces an innovative rotary shear system(RSS)to address these deficiencies through controlled mandrel rotation and cooling rates.We successfully prepared self-reinforced HDPE pipes with a three-layer structure combining spherical and shish-kebab crystals.Rotational processing aligned the molecular chains in the ring direction and formed shish-kebab crystals.As a result,the annular tensile strength of the rotationally processed three-layer shish-kebab structure(TSK)pipe increased from 26.7 MPa to 76.3 MPa,an enhancement of 185.8%.Notably,while maintaining excellent tensile strength(73.4 MPa),the elongation at break of the spherulite shishkebab spherulite(SKS)tubes was improved to 50.1%,as compared to 33.8%in the case of shish-kebab spherulite shish-kebab(KSK)tubes.This improvement can be attributed to the changes in the micro-morphology and polymer structure within the SKS tubes,specifically due to the formation of small-sized shish-kebab crystals and the low degrees of interlocking.In addition,2D-SAXS analysis revealed that KSK tubes have higher tensile strength due to smaller crystal sizes and larger shish dimensions,forming dense interlocking structures.In contrast,the SKS and TSK tubes had thicker amorphous regions and smaller shish sizes,resulting in reduced interlocking and mechanical performance. 展开更多
关键词 High-density polyethylene pipe SHISH-KEBAB Circumferential tensile strength Rotational shear Multilayer structure
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Isolation methods of exosomes derived from dental stem cells
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作者 Paras Ahmad Nathan Estrin +2 位作者 Nima Farshidfar Yufeng Zhang Richard J.Miron 《International Journal of Oral Science》 2025年第4期487-504,共18页
Mesenchymal stem cells are highly regarded for their potential in tissue repair and regenerative medicine due to their multipotency and self-renewal abilities.Recently,mesenchymal stem cells have been redefined as“me... Mesenchymal stem cells are highly regarded for their potential in tissue repair and regenerative medicine due to their multipotency and self-renewal abilities.Recently,mesenchymal stem cells have been redefined as“medical signaling cells,”with their primary biological effects mediated through exosome secretion.These exosomes,which contain lipids,proteins,RNA,and metabolites,are crucial in regulating various biological processes and enhancing regenerative therapies.Exosomes replicate the effects of their parent cells while offering benefits such as reduced side effects,low immunogenicity,excellent biocompatibility,and high drug-loading capacity.Dental stem cells,including those from apical papilla,gingiva,dental pulp,and other sources,are key contributors to exosome-mediated regenerative effects,such as tumor cell apoptosis,neuroprotection,angiogenesis,osteogenesis,and immune modulation.Despite their promise,clinical application of exosomes is limited by challenges in isolation techniques.Current methods face issues of complexity,inefficiency,and insufficient purity,hindering detailed analysis.Recent advancements,such as micro-electromechanical systems,alternating current electroosmosis,and serum-free three-dimensional cell cultures,have improved exosome isolation efficacy.This review synthesizes nearly 200 studies on dental stem cell-derived exosomes,highlighting their potential in treating a wide range of conditions,including periodontal diseases,cancer,neurodegenerative disorders,diabetes,and more.Optimized isolation methods offer a path forward for overcoming current limitations and advancing the clinical use of exosome-based therapies. 展开更多
关键词 stem cells EXOSOMES isolation methods mesenchymal stem cells regenerative medicine regulating various biological processes enhancing regenerative therapiesexosomes dental stem cells
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Role of Suspended Sediments and Mixing in Reducing Photoinhibition in the Bloom-Forming Cyanobacterium Microcystis
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作者 Justin D. Chaffin Thomas B. Bridgeman +1 位作者 Scott A. Heckathorn Ann E. Krause 《Journal of Water Resource and Protection》 2012年第12期1029-1041,共13页
Toxic cyanobacterial blooms are becoming a global problem. Previous research of cyanobacterial bloom development has examined how high nutrient concentrations promote cyanobacteria dominance, and how positive buoyancy... Toxic cyanobacterial blooms are becoming a global problem. Previous research of cyanobacterial bloom development has examined how high nutrient concentrations promote cyanobacteria dominance, and how positive buoyancy provides an ecological advantage over sinking phytoplankton. Tributaries responsible for loading nutrients into lakes often simultaneously contribute high concentrations of suspended sediments. High concentrations of suspended sediments may also influence blooms by affecting the ambient light climate, reducing photodamage, and increasing the efficiency of photosynthesis. We examined the effects of sediments and vertical mixing in potentially reducing photodamage to Microcystis by measuring photosynthetic parameters and pigment content of Microcystis in western Lake Erie during the 2008 bloom and in laboratory experiments. Photosynthetic efficiency increased with increasing sediment concentration in the lake and laboratory experiment. Content of photo-protective carotenoid pigments per dry weight decreased with increasing sediment concentrations, while the light-harvesting pigments, chl a and phycocyanin, increased with sediments. These results indicate that suspended sediments reduce photoinhibition for Microcystis. Further, photosynthetic damage was higher when Microcystis was concentrated on the surface compared to a mixed water column. Measurements of Microcystis abundance and light were also recorded, in addition to photosynthetic measurements. Greatest Microcystis abundances in Lake Erie were recorded during light-limiting conditions, which offer Microcystis both physiological and ecological benefits by reducing photoinhibition and increasing Microcystis’ advantage in light competition via buoyancy. Efforts to reduce cyanobacterial blooms may include reducing suspended sediments loads in combination with reducing nutrient loading. 展开更多
关键词 CHLOROPHYLL Fluorescence CYANOBACTERIA Harmful Algae BLOOM Lake Erie MICROCYSTIS Suspended Sediments
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Nitrogen Constrains the Growth of Late Summer Cyanobacterial Blooms in Lake Erie 被引量:3
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作者 Justin D. Chaffin Thomas B. Bridgeman Darren L. Bade 《Advances in Microbiology》 2013年第6期16-26,共11页
Phosphorus (P) is generally considered to be the main limiting nutrient to freshwater phytoplankton productivity. However, recent research is drawing attention to the importance of nitrogen (N) in freshwater eutrophic... Phosphorus (P) is generally considered to be the main limiting nutrient to freshwater phytoplankton productivity. However, recent research is drawing attention to the importance of nitrogen (N) in freshwater eutrophication and N often constrains growth of cyanobacteria in small lakes. In this study we determined phytoplankton nutrient limitation in a large lake, Lake Erie during two growing seasons. During 2010 and 2011, nutrient enrichment bioassays (+P, +N and, +P and N) were conducted monthly from June through September with water collected in Maumee Bay (site MB18) and in the center of the western basin (site WBC). Nutrient concentrations were monitored every other week. At MB18, total P concentration was often >3 mmol/L and nitrate concentration decreased from >250 mmol/L in early summer to mmol/L in late summer. Nitrogen and P levels were about five-fold less at WBC. Bioassays indicated that phytoplankton nutrient limitation varied in summer, spatially, and even among phytoplankton groups. For site MB18, +P increased chlorophyll concentration in one of the eight bioassays, indicating that P did not typically limit production. For site WBC, +P increased chlorophyll concentration in six of the eight bioassays. As a result of very low ambient nitrate concentration (mmol/L) in late summer, +N (without P) increased chlorophyll concentration, suggesting symptoms of N-limitation. The N-fixing cyanobacterium Anabaena became dominant following N-limitation. This study highlights the need to reduce P loading to restore water quality. Furthermore, due to low nitrate concentration, the severity of the cyanobacterial blooms could be worse if not for N-limitation in western Lake Erie. 展开更多
关键词 CYANOBACTERIA EUTROPHICATION NITROGEN Phosphorus PHYTOPLANKTON
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Approximate Electromagnetic Cloaking of a Dielectric Sphere Using Homogeneous Isotropic Multi-Layered Materials
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作者 Hany M. Zamel Essam El Diwany Hadia El Hennawy 《Journal of Electromagnetic Analysis and Applications》 2013年第10期379-387,共9页
In cloaking, a body is hidden from detection by surrounding it by a coating consisting of an unusual anisotropic nonhomogeneous material. The permittivity and permeability of such a cloak are determined by the coordin... In cloaking, a body is hidden from detection by surrounding it by a coating consisting of an unusual anisotropic nonhomogeneous material. The permittivity and permeability of such a cloak are determined by the coordinate transformation of compressing a hidden body into a point or a line. The radially-dependent spherical cloaking shell can be approximately discretized into many homogeneous anisotropic layers;each anisotropic layer can be replaced by a pair of equivalent isotropic sub-layers, where the effective medium approximation is used to find the parameters of these two equivalent sub-layers. In this work, the scattering properties of cloaked dielectric sphere is investigated using a combination of approximate cloaking, where the dielectric sphere is transformed into a small sphere rather than to a point, together with discretizing the cloaking material using pairs of homogeneous isotropic sub-layers. The back-scattering normalized radar cross section, the scattering patterns are studied and the total scattering cross section against the frequency for different number of layers and transformed radius. 展开更多
关键词 APPROXIMATE CLOAKING Dielectric SPHERE CLOAKING by Layered ISOTROPIC MATERIALS
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Automated Colorization of Grayscale Images Using Texture Descriptors and a Modified Fuzzy C-Means Clustering
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作者 Christophe Gauge Sreela Sasi 《Journal of Intelligent Learning Systems and Applications》 2012年第2期135-143,共9页
A novel example-based process for Automated Colorization of grayscale images using Texture Descriptors (ACTD) without any human intervention is proposed. By analyzing a set of sample color images, coherent regions of ... A novel example-based process for Automated Colorization of grayscale images using Texture Descriptors (ACTD) without any human intervention is proposed. By analyzing a set of sample color images, coherent regions of homogeneous textures are extracted. A multi-channel filtering technique is used for texture-based image segmentation, combined with a modified Fuzzy C-means (FCM) clustering algorithm. This modified FCM clustering algorithm includes both the local spatial information from neighboring pixels, and the spatial Euclidian distance to the cluster’s center of gravity. For each area of interest, state-of-the-art texture descriptors are then computed and stored, along with corresponding color information. These texture descriptors and the color information are used for colorization of a grayscale image with similar textures. Given a grayscale image to be colorized, the segmentation and feature extraction processes are repeated. The texture descriptors are used to perform Content-Based Image Retrieval (CBIR). The colorization process is performed by Chroma replacement. This research finds numerous applications, ranging from classic film restoration and enhancement, to adding valuable information into medical and satellite imaging. Also, this can be used to enhance the detection of objects from x-ray images at the airports. 展开更多
关键词 Image Processing PATTERN Recognition COMPUTER VISION Fuzzy C-MEANS Clustering GABOR
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Molecular Dynamics Simulations and Experimental Investigations of Atomic Diffusion Behavior at Bonding Interface in an Explosively Welded Al/Mg Alloy Composite Plate 被引量:14
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作者 Ting-Ting Zhang Wen-Xian Wang +3 位作者 Jun Zhou Xiao-Qing Cao Rui-Shan Xie Yi Wei 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2017年第10期983-991,共9页
In this study, 6061 aluminum alloy and AZ31 B magnesium alloy composite plate was fabricated through explosive welding. Molecular dynamics(MD) simulations were conducted to investigate atomic diffusion behavior at b... In this study, 6061 aluminum alloy and AZ31 B magnesium alloy composite plate was fabricated through explosive welding. Molecular dynamics(MD) simulations were conducted to investigate atomic diffusion behavior at bonding interface in the AI/Mg composite plate. Corresponding experiments were conducted to validate the simulation results. The results show that diffusion coefficient of Mg atom is larger than that of A1 atom and the difference between these two coefficients becomes smaller with increasing collision velocity. The diffusion coefficient was found to depend on collision velocity and angle. It increases linearly with collision velocity when the collision angle is maintained constant at 10° and decreases linearly with collision angle when the collision velocity is maintained constantly at 440 m/s. Based on our MD simulation results and Fick's second law, a mathematical formula to calculate the thickness of diffusion layer was proposed and its validity was verified by relevant experiments. Transmission electron microscopy and energy-dispersive system were also used to investigate the atomic diffusion behavior at the bonding interface in the explosively welded 6061/AZ31B composite plate. The results show that there were obvious Al and Mg atom diffusion at the bonding interface,and the diffusion of magnesium atoms from magnesium alloy plate to aluminum alloy plate occurs much faster than the diffusion of aluminum atoms to the magnesium alloy plate. These findings from the current study can help to optimize the explosive welding process. 展开更多
关键词 Al/Mg composite plate Explosive welding Molecular dynamics simulation Atomic diffusionbehavior
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Series solutions of annular axisymmetric stagnation flow and heat transfer on moving cylinder 被引量:1
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作者 A.MASTROBERARDINO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第9期1043-1054,共12页
The steady, laminar, incompressible flow and heat transfer of a viscous fluid between two circular cylinders for two different types of thermal boundary conditions are investigated. The governing Navier-Stokes and the... The steady, laminar, incompressible flow and heat transfer of a viscous fluid between two circular cylinders for two different types of thermal boundary conditions are investigated. The governing Navier-Stokes and thermal equations of the flow are reduced to a nonlinear system of ordinary differential equations. The equations are solved analyt- ically using the homotopy analysis method (HAM). Convergence of the HAM solutions is discussed in detail. These solutions are then compared with recently obtained numericM and perturbative solutions. Plots of the velocity and temperature profiles are provided for various values of the relevant parameters. 展开更多
关键词 stagnation flow heat transfer moving cylinder boundary value problem homotopy analysis method (HAM)
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Prediction of fracture limits of Ni-Cr based alloy under warm forming condition using ductile damage models and numerical method 被引量:3
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作者 Ayush MORCHHALE Anand BADRISH +4 位作者 Nitin KOTKUNDE Swadesh Kumar SINGH Navneet KHANNA Ambuj SAXENA Chetan NIKHARE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第8期2372-2387,共16页
The stretch forming and the deep-drawing processes were carried out at 300 and 673 K to determine the safe forming and fracture limits of IN625 alloy.The experimentally obtained strain-based fracture forming limit dia... The stretch forming and the deep-drawing processes were carried out at 300 and 673 K to determine the safe forming and fracture limits of IN625 alloy.The experimentally obtained strain-based fracture forming limit diagram(FFLD)was transformed into a stress-based(σ-FFLD)and effective plastic strain(EPS)vs triaxiality(η)plot to remove the excess dependency of fracture limits over the strains.For the prediction of fracture limits,seven different damage models were calibrated.The Oh model displayed the best ability to predict the fracture locus with the least absolute error.Though the experimentally obtained fracture limits have only been used for the numerical analysis,none of the considered damage models predicted the fracture strains over the entire considered range of stress triaxiality(0.33<η<0.66).The deep drawing process window helped to determine wrinkling,safe and fracture zones while drawing the cylindrical cups under different temperature and lubricating conditions.Further,the highest drawing ratio of 2 was achieved at 673 K under the lubricating condition.All the numerically predicted results of both stretch forming and deep drawing processes using the Hill 1948 anisotropic yielding function were found to be good within the acceptable range of error. 展开更多
关键词 IN625 alloy warm forming ductile damage models FORMABILITY forming limit diagram deep drawing processing window finite element analysis
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Relationship between the severity of hepatitis C virus-related liver disease and the presence of Helicobacter species in the liver: A prospective study 被引量:3
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作者 Laurent Castéra Anne Pedeboscq +12 位作者 Marcia Rocha Brigitte Le Bail Corinne Asencio Victor de Lédinghen Pierre-Henri Bernard Christophe Laurent Marie-Edith Lafon Maylis Capdepont Patrice Couzigou Paulette Bioulac-Sage Charles Balabaud FrancisMégraud Armelle Ménard 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第45期7278-7284,共7页
AIM: To determine the presence of Helicobacter species DNA in the liver of chronic hepatitis C (CHC) patients with and without cirrhosis as compared to controls, and to identify the bacterial species involved. METHODS... AIM: To determine the presence of Helicobacter species DNA in the liver of chronic hepatitis C (CHC) patients with and without cirrhosis as compared to controls, and to identify the bacterial species involved. METHODS: Seventy-nine consecutive patients (HBV and HIV negative) with a liver sample obtained after liver biopsy or hepatic resection were studied: 41 with CHC without cirrhosis, 12 with CHC and cirrhosis, and 26 controls (HCV negative). Polymerase chain reactions (PCRs) targeting Helicobacter 16S rDNA and species- specific were performed on DNA extracted from the liver. A gastric infection with H pylori was determined by serology and confirmed by 13C-urea breath test. RESULTS: Overall, Helicobacter 16S rDNA was found in 16 patients (20.2%). Although positive cases tended to be higher in CHC patients with cirrhosis (41.6%) than in those without cirrhosis (17.0%) or in controls (15.4%), the difference was not statistically significant (P =0.08). H pylori-like DNA was identified in 12 cases and H. pullorum DNA in 2, while 2 cases remained unidenti- fied. Gastric infection with H pylori was found in only 2 of these patients. CONCLUSION: Our results do not confirm the associ- ation of Helicobacter species DNA in the liver of CHC patients with advanced liver disease. The lack of correlation between positive H pylori serology and the presence of H pylori-like DNA in the liver may indicate the presence of a variant of this species. 展开更多
关键词 Hepatitis C virus HEPATITIS CIRRHOSIS HELICOBACTER
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STELCO-LAKE ERIE厂低硫钢的生产 被引量:1
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作者 Mark S. Fenton Ron H. Merk Blair A. Otterman 《重钢技术》 2006年第1期16-21,共6页
Stelco Lake Erie厂(LEW)生产满足要求的低硫钢和超低硫钢。本文将详细讨论在炼钢实践中,LEW成功生产的抗氢质裂纹(HIC)等级为X52的ERW线材(其硫含量低于15ppm)以及HSLA类钢种(其硫含量低于50ppm)。
关键词 超低硫钢 生产 硫含量 HSL 炼钢
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Vigna radiata var. GM4 Plant Growth Enhancement and Root Colonization by a Multi-Metal-Resistant Plant Growth-Promoting Bacterium Enterobacter sp. C1D in Cr(VI)-Amended Soils 被引量:1
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作者 Gangavarapu SUBRAHMANYAM Rakesh Kumar SHARMA +1 位作者 Gattupalli Naresh KUMAR Gattupalli ARCHANA 《Pedosphere》 SCIE CAS CSCD 2018年第1期144-156,共13页
Contamination of agricultural soils by heavy metals has become a major concern due to their toxic effects on plant growth,symbiosis and consequently the yields of crops. In the present study, to enhance plant growth i... Contamination of agricultural soils by heavy metals has become a major concern due to their toxic effects on plant growth,symbiosis and consequently the yields of crops. In the present study, to enhance plant growth in Cr(VI)-amended soils, novel metalresistant plant growth-promoting bacteria(PGPB) were isolated from a soil contaminated with industrial waste effluent. One of the bacterial isolates, identified as Enterobacter sp. C1 D by 16 S r RNA gene sequencing, was found to be multi-metal resistant in nature with excellent plant growth-promoting(PGP) traits. Mung bean(Vigna radiata var. GM4) inoculation with Enterobacter sp.C1 D significantly(P &lt; 0.01) increased root and shoot length, shoot and root weight, and chlorophyll content in a range of Cr(VI)treatments. Plant tolerance towards Cr(VI) measured as effective concentration showed higher values with Enterobacter sp. C1 Dtreated plants compared to un-inoculated plants. Root colonization study was also carried out using green fluorescence protein-labeled Enterobacter sp. C1 D under a hydroponic system. Confocal laser scanning microscopy of the plant roots showed heavy bacterial loads on the surface of the plant root specifically at the root tip and the point of root hair/lateral root formation. The results of PGP traits showed that elevated indole acetic acid levels and 1-aminocyclopropane-1-carboxylate deaminase activity enabled Enterobacter sp. C1 D to enhance V. radiata growth in Cr(VI)-amended soils, whereby it significantly increased plant tolerance towards elevated Cr(VI) concentrations. 展开更多
关键词 chromium(VI) Enterobacter sp C1D heavy metal metal toxicity plant tolerance
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Excellent femoral outcomes when all access attempts and closure devices are performed by experienced cardiologists
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作者 Kevin S. Kang Quentin Orlando +2 位作者 Robert Maholic Richard Petrella Gurjaipal S. Kang 《World Journal of Cardiovascular Diseases》 2013年第9期569-572,共4页
Femoral access is considered less safe for access site complications than the radial access. Cardiovascular procedures have not been studied taking operator experience, defined as American Board of Internal Medicine, ... Femoral access is considered less safe for access site complications than the radial access. Cardiovascular procedures have not been studied taking operator experience, defined as American Board of Internal Medicine, Interventional Cardiology certification or equivalent qualification in another country, into account. We hypothesize that the procedural results are operator dependent and excellent results are obtained when procedures are performed by experienced operators. Femoral access is higher risk than radial access based on American College of Cardiology (ACC) guidelines. Femoral access is less forgiving, as opposed to radial, as it is an end-artery, lacks easy compressibility and is more likely to cause morbidity when injured. Hence, radial is recommended over the femoral approach according to ACC practice guidelines. These guidelines are often based on the randomized studies from academic centers where trainees, with variable arterial access experience, perform the initial access stick and arterial closure device deployment. Methods: We performed a single center retrospective review of 32,446 consecutive patients undergoing invasive cardiovascular procedures done from the femoral approach using American College of Cardiology/National Cardiovascular Data Registry (ACC/NCDR) from January 1, 2006 to June 30, 2013. Only experienced operators performed the actual access site stick and the reminder of the invasive procedure. Results: Total bleeding and vascular complications were less than 1%. We define outcomes as excellent if the total bleeding and vascular complication risk is less than 1% based on previous studies discussed in the ACC guidelines. Conclusion: Excellent outcomes can be obtained from the femoral access if experienced cardiologists perform the procedure. Hence, radial arterial access over the femoral access may be selectively rather than universally recommended considering the possibility of varying level of femoral access expertise of different practices. 展开更多
关键词 OPERATORS ACCESS COMPLICATIONS
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Coronary computed tomography angiography vs stress testing for stable angina evaluation:Diagnostic and prognostic superiority
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作者 Vinay Gundareddy Shivam Singla +7 位作者 Jupalle Mounika Okello Owona Bhavna Singla Taranpreet Singh Sidra Anwar Vignesh Ramachandran Hikmat Ullah Shabbir Mazari 《World Journal of Cardiology》 2025年第9期64-72,共9页
BACKGROUND Stable angina pectoris,a clinical manifestation of coronary artery disease(CAD),is commonly evaluated using non-invasive diagnostic tools.Traditionally,stress testing modalities such as exercise electrocard... BACKGROUND Stable angina pectoris,a clinical manifestation of coronary artery disease(CAD),is commonly evaluated using non-invasive diagnostic tools.Traditionally,stress testing modalities such as exercise electrocardiography(ECG),myocardial per-fusion imaging(MPI),and stress echocardiography have been the first-line stra-tegies.However,coronary computed tomography angiography(CCTA),an anatomic imaging modality,is increasingly used for its ability to directly visualize coronary artery stenoses and plaque burden.Despite growing adoption,the comparative effectiveness of CCTA and stress testing in terms of diagnostic accuracy,prognostic value,and clinical outcomes in stable angina remains an area of active debate.AIM To compare the diagnostic and prognostic performance of CCTA with various forms of stress testing in adult patients presenting with suspected or confirmed stable angina.METHODS A comprehensive literature search was performed across PubMed,EMBASE,Scopus,and the Cochrane Central Register of Controlled Trials in accordance with the PRISMA guidelines.Only randomized controlled trials(RCT)published in English within the last 15 years were included.Studies involving adult patients(≥18 years)with stable angina or low-risk chest pain were selected.The intervention was CCTA,and the comparators included ECG,MPI,and stress echocardiography.Data were extracted using a standardized process,and study quality was assessed using the Cochrane Risk of Bias 2.0 tool.Due to heterogeneity in outcome measures and modalities,narrative synthesis was employed.RESULTS Five high-quality RCTs encompassing a total of 5551 patients were included.CCTA demonstrated superior diagnostic accuracy and prognostic capability across multiple studies.It was more effective in predicting major adverse cardiac events,including myocardial infarction and cardiac death,and was associated with fewer un-necessary invasive coronary angiographies and better event-free survival.Studies also reported improved revascu-larization rates in patients evaluated with CCTA,particularly within tiered diagnostic protocols.Stress testing,while useful,showed limitations in sensitivity and downstream clinical decision-making.CONCLUSION CCTA offers a diagnostically superior and clinically impactful strategy for the initial evaluation of patients with stable angina,especially those with intermediate pretest probability of CAD.Compared to conventional stress testing,it enhances risk stratification,reduces unnecessary procedures,and may improve long-term outcomes.These findings support its broader integration into diagnostic pathways for stable angina. 展开更多
关键词 Coronary computed tomography angiography Stable angina Stress testing Myocardial perfusion imaging Diagnostic accuracy Prognostic evaluation Event-free survival Non-invasive cardiac imaging Revascularization Coronary artery disease
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FeS2@C nanorods embedded in three-dimensional graphene as high-performance anode for sodium-ion batteries 被引量:2
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作者 Zhenxiao Lu Wenxian Wang +1 位作者 Jun Zhou Zhongchao Bai 《Frontiers of Materials Science》 SCIE CSCD 2020年第3期255-265,共11页
FeS2 has drawn tremendous attention as electrode material for sodium-ion batteries(SIBs)due to its high theoretical capacity and abundant resources.However,it suffers from severe volume expansion and dull reaction kin... FeS2 has drawn tremendous attention as electrode material for sodium-ion batteries(SIBs)due to its high theoretical capacity and abundant resources.However,it suffers from severe volume expansion and dull reaction kinetics during the cycling process,leading to poor rate capacity and short cyclability.Herein,a well-designed FeS2@C/G composite constructed by FeS2 nanoparticles embedded in porous carbon nanorods(FeS2@C)and covered by three-dimensional(3D)graphene is reported.FeS2 nanoparticles can shorten the Na+diffusion distance during the sodiation-desodiation process.Porous carbon nanorods and 3D graphene not only improve conductivity but also provide double protection to alleviate the volume variation of FeS2 during cycling.Consequently,FeS2@C/G exhibits excellent cyclability(83.3%capacity retention after 300 cycles at 0.5A·g−1 with a capacity of 615.1 mA·h·g−1)and high rate capacity(475.1 mA·h·g−1 at 5A·g−1 after 2000 cycles).The pseudocapacitive process is evaluated and confirmed to significantly contribute to the high rate capacity of FeS2@C/G. 展开更多
关键词 FeS2 electrode material sodium-ion battery nanoparticles GRAPHENE
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Patient factors in responders and non-responders treated with steroids for acute alcohol-associated hepatitis 被引量:1
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作者 Kent W Sabatose Alexandra Baker +9 位作者 Kevin Kugler Jude Delikat Bethany Jowers Ambuj Kumar Sadaf Aslam Jacentha Buggs Christine Machado-Denis Nyingi Kemmer Kiran Dhanireddy Rashid Syed 《World Journal of Hepatology》 2025年第8期217-222,共6页
BACKGROUND Steroids remain the primary treatment for severe alcohol-associated hepatitis(AAH),though there is little available tools to predict patient response to steroids.It was hypothesized that phosphatidylethanol... BACKGROUND Steroids remain the primary treatment for severe alcohol-associated hepatitis(AAH),though there is little available tools to predict patient response to steroids.It was hypothesized that phosphatidylethanol(PEth)value will inversely corre-late with response to steroid therapy based on Lille score in AAH.AIM To assess the relationship of patient factors,focusing on pre-steroid therapy PEth value,to steroid therapy response in AAH.METHODS A retrospective case control study was performed on patients who received≥4 days of steroid therapy for AAH at our hospital between July 1,2019 and June 30,2022.A total of 2087 patients were screened for AAH and those treated with steroids were included for statistical analysis utilizing independent sample t-test and for categorical variables using the χ^(2) test.RESULTS No correlation was found between PEth value,pre-steroids abstinence length,or number of drinks per week pre-steroids and response to steroids.Non-responder status significantly correlated with older age(P=0.024),lower albumin(P=0.003),and higher bilirubin(P=0.010)pre-steroids.Our study suggests that age,pre-steroid albumin,and pre-steroid bilirubin levels may predict nonresponse to steroid therapy.Non-responders have increased incidence of death and higher medical costs.CONCLUSION Identifying non-responders through these identified factors should prompt early referral for liver transplantation.Future prospective studies with larger population size are needed to assess the efficacy of combined pre-steroid age,albumin,bilirubin and other biochemical markers as predictors of steroid response. 展开更多
关键词 Acute alcohol-associated hepatitis STEROIDS Transplant Steroid response PHOSPHATIDYLETHANOL
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Aspect-Oriented Modeling and Verification with Finite State Machines
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作者 徐殿祥 Omar El-Ariss +1 位作者 许巍峰 王林章 《Journal of Computer Science & Technology》 SCIE EI CSCD 2009年第5期949-961,共13页
Aspect-oriented programming modularizes crosscutting concerns into aspects with the advice invoked at the specified points of program execution. Aspects can be used in a harmful way that invalidates desired properties... Aspect-oriented programming modularizes crosscutting concerns into aspects with the advice invoked at the specified points of program execution. Aspects can be used in a harmful way that invalidates desired properties and even destroys the conceptual integrity of programs. To assure the quality of an aspect-oriented system, rigorous analysis and design of aspects are highly desirable. In this paper, we present an approach to aspect-oriented modeling and verification with finite state machines. Our approach provides explicit notations (e.g., pointcut, advice and aspect) for capturing crosscutting concerns and incremental modification requirements with respect to class state models. For verification purposes, we compose the aspect models and class models in an aspect-oriented model through a weaving mechanism. Then we transform the woven models and the class models not affected by the aspects into FSP (Finite State Processes), which are to be checked by the LTSA (Labeled Transition System Analyzer) model checker against the desired system properties. We have applied our approach to the modeling and verification of three aspect-oriented systems. To further evaluate the effectiveness of verification, we created a large number of flawed aspect models and verified them against the system requirements. The results show that the verification has revealed all flawed models. This indicates that our approach is effective in quality assurance of aspect-oriented state models. As such, our approach can be used for model-checking state-based specification of aspect-oriented design and can uncover some system design problems before the system is implemented. 展开更多
关键词 aspect-oriented modeling finite state machines MODELING VERIFICATION model checking
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Role of PD-1/PD-L1 signaling axis in oncogenesis and its targeting by bioactive natural compounds for cancer immunotherapy
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作者 Yogesh Godiyal Drishti Maheshwari +4 位作者 Hiroaki Taniguchi Shweta S.Zinzuwadia Yanelys Morera-Díaz Devesh Tewari Anupam Bishayee 《Military Medical Research》 2025年第10期1567-1616,共50页
Cancer is a global health problem and one of the leading causes of mortality.Immune checkpoint inhibitors have revolutionized the field of oncology,emerging as a powerful treatment strategy.A key pathway that has garn... Cancer is a global health problem and one of the leading causes of mortality.Immune checkpoint inhibitors have revolutionized the field of oncology,emerging as a powerful treatment strategy.A key pathway that has garnered considerable attention is programmed cell death-1(PD-1)/programmed cell death-ligand 1(PD-L1).The interaction between PD-L1 expressed on tumor cells and PD-1 reduces the innate immune response and thus compromises the capability of the body’s immune system.Furthermore,it controls the phenotype and functionality of innate and adaptive immune components.A range of monoclonal antibodies,including avelumab,atezolizumab,camrelizumab,dostarlimab,durvalumab,sinitilimab,toripalimab,and zimberelimab,have been developed for targeting the interaction between PD-1 and PD-L1.These agents can induce a broad spectrum of autoimmune-like complications that may affect any organ system.Recent studies have focused on the effect of various natural compounds that inhibit immune checkpoints.This could contribute to the existing arsenal of anticancer drugs.Several bioactive natural agents have been shown to affect the PD-1/PD-L1 signaling axis,promoting tumor cell apoptosis,influencing cell proliferation,and eventually leading to tumor cell death and inhibiting cancer progression.However,there is a substantial knowledge gap regarding the role of different natural compounds targeting PD-1 in the context of cancer.Hence,this review aims to provide a common connection between PD-1/PD-L1 blockade and the anticancer effects of distinct natural molecules.Moreover,the primary focus will be on the underlying mechanism of action as well as the clinical efficacy of bioactive molecules.Current challenges along with the scope of future research directions targeting PD-1/PD-L1 interactions through natural substances are also discussed. 展开更多
关键词 Cancer Programmed cell death-1(PD-1)/programmed cell death-ligand 1(PD-L1) CROSSTALK Natural compounds Therapeutic targets
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Malakoplakia in kidney transplant recipients:Three case reports
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作者 Prathap Kumar Simhadri Renish Contractor +7 位作者 Deepak Chandramohan Matthew McGee Udit Nangia Mohammad Atari Syed Bushra Sanjana Kapoor Ramya Krishna Velagapudi Pradeep K Vaitla 《World Journal of Nephrology》 2025年第2期147-157,共11页
BACKGROUND Malakoplakia is a rare chronic granulomatous disease associated with gramnegative infection,predominantly by Escherichia coli.It is induced by defective phagolysosomal activity of the macrophages.Malakoplak... BACKGROUND Malakoplakia is a rare chronic granulomatous disease associated with gramnegative infection,predominantly by Escherichia coli.It is induced by defective phagolysosomal activity of the macrophages.Malakoplakia commonly affects the urinary bladder but has been shown to affect any solid organ,including the native and transplanted kidney.However,isolated malakoplakia of the kidney allograft is rare.Transplant recipients with compromised immune systems are more likely to develop malakoplakia.CASE SUMMARY We report three cases of kidney allograft parenchymal malakoplakia in kidney transplant recipients on immunosuppression that were successfully managed with good outcomes.We described the clinical characteristics of all the kidney allograft malakoplakia cases documented in the literature.A total of 55 cases of malakoplakia were reported in recipients with a history of kidney transplant.A total of 27 recipients had malakoplakia involving the allograft,and others had malakoplakia in other organs.The common presentations included allograft dysfunction,pyelonephritis,and allograft or systemic mass.Most recipients had favorable outcomes with appropriate management that included prolonged antibiotic therapy and adjustment of immunosuppression.We reviewed the published literature on all the cases of malakoplakia in kidney transplant recipients so far and summarized the etiology,management,and outcomes.CONCLUSION This case series provides an overview of the etiology,presentation,pathogenesis,and management of malakoplakia in kidney transplant recipients. 展开更多
关键词 Renal transplant MALAKOPLAKIA Allograft malakoplakia Michaelis-Gutmann bodies Von Hansemann cells Transplant malakoplakia Case report
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基于环境DNA技术的珠江中下游鱼类多样性初步研究 被引量:4
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作者 朱书礼 陈蔚涛 +4 位作者 武智 夏雨果 杨计平 李跃飞 李捷 《南方水产科学》 CAS CSCD 北大核心 2024年第1期120-129,共10页
通过环境DNA技术(Environmental DNA,eDNA)检测珠江中下游鱼类生物多样性,探索珠江中下鱼类多样性监测和保护的新途径。2023年2月在珠江中下游设置了桂平、藤县、封开、德庆、肇庆和九江共6个采样点,通过水样采集及过滤、eDNA提取、遗... 通过环境DNA技术(Environmental DNA,eDNA)检测珠江中下游鱼类生物多样性,探索珠江中下鱼类多样性监测和保护的新途径。2023年2月在珠江中下游设置了桂平、藤县、封开、德庆、肇庆和九江共6个采样点,通过水样采集及过滤、eDNA提取、遗传标记扩增及测序和数据库比对分析等流程检测鱼类多样性。结果表明,6个采样点共检测出30种鱼类,隶属于4目10科27属,其中土著鱼类26种,外来种4种。较已有传统调查数据新检出2种鱼类:美丽沙鳅(Botia pulchra)和齐氏罗非鱼(Oceochromis zillii)。鱼类优势种为子陵吻鰕虎鱼(Rhinogobius giurinus)、瓦氏黄颡鱼(Pelteobagrus vachellii)、鲢(Hypophthalmichthys molitrix)、尼罗罗非鱼(O.nilotica)、齐氏罗非鱼、南方波鱼(Rasbora steineri)和鲤(Cyprinus carpio)。根据Shannon指数和Simpson指数显示,eDNA检测九江和桂平站点的鱼类多样性最高,藤县的最低。作为一种新的检测方法,eDNA技术可用于快速检测珠江中下游鱼类的多样性及分布,在实际应用中可将eDNA技术与传统的监测方法相结合,以提供更全面的鱼类生物多样性数据信息。 展开更多
关键词 环境DNA(eDNA) 鱼类多样性 珠江中下游
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