期刊文献+
共找到516,632篇文章
< 1 2 250 >
每页显示 20 50 100
Short-term and long-term effects of sevoflurane inhalation vs propofol total intravenous anesthesia in gastrectomy for gastric cancer
1
作者 Zhi Wang Ji-Wen Cheng Kuai-Yun Yu 《World Journal of Gastrointestinal Oncology》 2025年第11期91-102,共12页
BACKGROUND Gastric cancer is a major global health issue,and the perioperative period critic-ally influences patient outcomes.The different effects of sevoflurane inhalation anesthesia and propofol total intravenous a... BACKGROUND Gastric cancer is a major global health issue,and the perioperative period critic-ally influences patient outcomes.The different effects of sevoflurane inhalation anesthesia and propofol total intravenous anesthesia on intraoperative stability,postoperative complications,and long-term oncologic outcomes in patients with gastric cancer undergoing radical gastrectomy remain unclear.AIM To compare the effects of sevoflurane inhalation anesthesia and propofol total in-travenous anesthesia on clinical outcomes,including intraoperative indicators,postoperative complications,adverse effects,pain scores,and survival.METHODS This single-center retrospective cohort study included 204 patients who underw-ent radical gastrectomy for gastric cancer from February 2019 to December 2022.Patients were assigned to either the sevoflurane group(n=103)or the propofol group(n=101)based on intraoperative anesthetic regimen.Standardized protoc-ols for anesthesia management,intraoperative monitoring,and postoperative analgesia were applied.Baseline characteristics;intraoperative metrics;adverse events;complications;Visual Analog Scale(VAS)scores at 2,4,6,24,and 48 hours;and survival outcomes were retrospectively collected.Group comparisons were performed usingχ2 for categorical variables,t test for continuous variables,RESULTS Baseline demographic and clinical characteristics were similar between groups.No significant differences were observed in intraoperative indicators or most 30-day postoperative outcomes,including length of stay,emergency department visits,and readmission rates.The propofol group showed elevated mean VAS pain score at 24 hours postoperatively,but no differences were found at other time points.The propofol group also had significantly higher postoperative nausea incidence and transiently higher systolic/diastolic blood pressure and heart rate at the time of incision than the sevoflurane group.No significant differences were seen in overall rates or severity of postoperative complications,intraoperative adverse events,or in overall survival and progression-free survival.CONCLUSION In patients undergoing radical gastrectomy for gastric cancer,sevoflurane and propofol anesthesia demonstrated similar profiles regarding intraoperative safety,postoperative complications,adverse events,postoperative pain,and long-term survival.The selection of anesthesia can be personalized without significantly affecting periop-erative or oncologic outcomes. 展开更多
关键词 Gastric cancer Radical gastrectomy ANESTHESIA SEVOFLURANE PROPOFOL long-term effects
暂未订购
Long-term effects of early antibiotic intervention on blood parameters,apparent nutrient digestibility, and fecal microbial fermentation profile in pigs with different dietary protein levels 被引量:9
2
作者 Miao Yu Chuanjian Zhang +4 位作者 Yuxiang Yang Chunlong Mu Yong Su Kaifan Yu Weiyun Zhu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第1期175-186,共12页
Backgroud: This study aimed to determine the effects of early antibiotic intervention(EAI) on subsequent blood parameters, apparent nutrient digestibility, and fecal fermentation profile in pigs with different diet... Backgroud: This study aimed to determine the effects of early antibiotic intervention(EAI) on subsequent blood parameters, apparent nutrient digestibility, and fecal fermentation profile in pigs with different dietary crude protein(CP) levels. Eighteen litters of piglets(total 212) were randomly allocated to 2 groups and were fed a creep feed diet with or without in-feed antibiotics(olaquindox, oxytetracycline calcium and kitasamycin) from postnatal d 7 to d 42. On d 42, the piglets within the control or antibiotic group were mixed, respectively, and then further randomly assigned to a normal-(20%, 18%, and 14% CP from d 42 to d 77, d 77 to d 120, and d 120 to d 185,respectively) or a low-CP diet(16%, 14%, and 10% CP from d 42 to d 77, d 77 to d 120, and d 120 to d 185,respectively), generating 4 groups. On d 77(short-term) and d 185(long-term), serum and fecal samples were obtained for blood parameters, microbial composition and microbial metabolism analysis.Results: EAI increased(P 〈 0.05) albumin and glucose concentrations in low-CP diet on d 77, and increased(P 〈 0.05) urea concentration in normal-CP diet. On d 185, EAI increased(P 〈 0.05) globulin concentration in normal-CP diets, but decreased glucose concentration. For nutrient digestibility, EAI increased(P 〈 0.05)digestibility of CP on d 77. For fecal microbiota, the EAI as well as low-CP diet decreased(P 〈 0.05) E. coli count on d 77. For fecal metabolites, on d 77, EAI decreased(P 〈 0.05) total amines concentration but increased skatole concentration in low-CP diet. On d 185, the EAI increased(P 〈 0.05) putrescine and total amines concentrations in low-CP diets but reduced(P 〈 0.05) in the normal-CP diets. The low-CP diet decreased the concentrations of these compounds.Conclusions: Collectively, these results indicate that EAI has short-term effects on the blood parameters and fecal microbial fermentation profile. The effects of EAI varied between CP levels, which was characterized by the significant alteration of glucose and putrescine concentration. 展开更多
关键词 Antibiotics long term effect Antimicrobial Blood parameters Low protein diet Metabolites Microbiota
在线阅读 下载PDF
Long-term effects of pattern scan laser pan-retinal photocoagulation on diabetic retinopathy in Chinese patients: a retrospective study 被引量:7
3
作者 Chuang-Xin Huang Kun-Bei Lai +6 位作者 Li-Jun Zhou Zhen Tian Xiao-Jing Zhong Fa-Bao Xu Ya-Jun Gong Lin Lu Chen-Jin Jin 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第2期239-245,共7页
●AIM:To evaluate the long-term effects of pattern scan laser(PASCAL)pan-retinal photocoagulation(PRP)on diabetic retinopathy(DR)in Chinese patients.●METHODS:In this retrospective study,we evaluated clinical data of ... ●AIM:To evaluate the long-term effects of pattern scan laser(PASCAL)pan-retinal photocoagulation(PRP)on diabetic retinopathy(DR)in Chinese patients.●METHODS:In this retrospective study,we evaluated clinical data of 29 patients(53 eyes)with severe non-proliferative DR(SNPDR)or proliferative DR(PDR)who received PRP and follow-up at our hospital from 2008 to 2013.Sixteen patients(29 eyes)received PASCAL PRP and 13 patients(24 eyes)received 100-ms conventional laser PRP.●RESULTS:After long-term follow-up(mean,min-max days:719.8,290-1666 for PASCAL PRP vs 743.5,240-1348 for conventional PRP,P=0.569),patients receiving PASCAL PRP required fewer photocoagulation sessions than the conventional PRP group(2.6±1.0 vs 3.9±0.9,P<0.01).Best corrected visual acuity(BCVA)was reduced slightly in PASCAL PRP group while reduced significantly in conventional PRP group.At last visit,24 eyes in the PASCAL group(88.9%)and 21 eyes in the conventional group(91.7%)were improved or stable.Two eyes in PASCAL PRP group(7.4%)and 3 eyes in the conventional PRP group(12.5%)developed vitreous hemorrhage or vitreous fibrovascular proliferation.●CONCLUSION:PASCAL PRP is as effective and may be more conducive to maintaining visual acuity with less treatment sessions for DR treatment compared to conventional laser PRP. 展开更多
关键词 PROLIFERATIVE DIABETIC RETINOPATHY severe non-proliferative DIABETIC RETINOPATHY PATTERN SCAN laser pan-retinal photocoagulation clinical effect
原文传递
Long-term effects of metformin use in gestational diabetes mellitus on offspring health
4
作者 Ayan Roy Jayaprakash Sahoo 《World Journal of Diabetes》 SCIE 2021年第11期1812-1817,共6页
Metformin is the first-line drug for the treatment of type 2 diabetes mellitus,but its role in gestational diabetes mellitus(GDM)management is not clear.Recent evidence suggests a certain beneficial effect of metformi... Metformin is the first-line drug for the treatment of type 2 diabetes mellitus,but its role in gestational diabetes mellitus(GDM)management is not clear.Recent evidence suggests a certain beneficial effect of metformin in the treatment of GDM,but a high treatment failure rate leads to the initiation of additional medications,such as insulin.Moreover,since metformin crosses the placental barrier and reaches a significant level in the fetus,it is likely to influence the fetal metabolic milieu.The evidence indicates the long-term safety in children exposed to metformin in utero except for mild adverse anthropometric profiles.Diligent follow-up of metformin-exposed offspring is warranted from the clinician’s point of view. 展开更多
关键词 ANTHROPOMETRY FETAL Gestational diabetes mellitus long-term METFORMIN OFFSPRING
暂未订购
Long-term effects of management systems on crop yield and soil physical properties of semi-arid tropics of Vertisols
5
作者 Prabhakar Pathak Suhas P Wani Raghavendra Rao Sudi 《Agricultural Sciences》 2011年第4期435-442,共8页
Long-term experiments can be used to assess management induced changes in soil properties and sustainability of the management system in terms of the productivity. Such data are scanty, especially in the semi-arid tro... Long-term experiments can be used to assess management induced changes in soil properties and sustainability of the management system in terms of the productivity. Such data are scanty, especially in the semi-arid tropics (SAT) region. A long-term experiment established in 1976 at ICRISAT in India on Vertisols with two management treatments;improved management (IM), comprising semi-permanent broadbed and furrow (BBF) landform with minimum tillage and improved cropping practices;and traditional management (TM) system comprising keeping the land fallow during the rainy season and sowing on flat landform during post-rainy season with traditional cropping practices, was sampled after 24 and 34 years for soil physical and hydrological properties. Results showed that both in short-and long-term the management systems had profound effect on crop yields. Also in the long-term IM and TM management systems had significant effect on several soil physical and hydrological properties. Throughout the soil profile IM systems had significantly lower bulk density, significantly higher porosity, substantially lower penetration resistance both at 5 cm (1 and 8 MPa) and 15 cm depths (8 and 15 MPa), significantly higher infiltration and sorptivity and significantly larger mean weight diameter of 4.3 mm compared to 2.8 mm for soils under TM. However, management systems had no significant effect on moisture holding capacities both at 0.033 and 1.5 MPa. Significant differences between the improved and traditional systems were observed in the size and pattern of soil surface cracks. Over the long-term, the improved management systems has very favorable effects on soil physical and hydrological properties and on the soil surface cracking and its patterns, thereby contributing to higher productivity. 展开更多
关键词 Broadbed and FURROW System Minimum TILLAGE long-term Experiment SUSTAINABILITY
暂未订购
A Prospective Study on Evaluating the Long-Term Effects of Childhood Vaccination from Birth to 13 Years Old in Kuwait
6
作者 Nedaa A. Al-Khamees 《Health》 2024年第10期932-969,共38页
Background: To prevent infectious diseases and deaths of children, vaccinations play a crucial role in public health strategies in Kuwait. However, it remained uncertain to demonstrate the potential long-term health o... Background: To prevent infectious diseases and deaths of children, vaccinations play a crucial role in public health strategies in Kuwait. However, it remained uncertain to demonstrate the potential long-term health outcomes of vaccination, including neurodevelopmental disorders (NDD) and autism. This study aimed to evaluate the long-term health outcomes of vaccination among Kuwait children from birth to thirteen years old. Objectives: This study included the significant objectives: (1) to compare long-term health effects, including chronic and acute conditions for unvaccinated, partially vaccinated, and vaccinated children, and (2) to evaluate the association of vaccination with the neurodevelopmental disorders (NDD) and autism, and the preventable illnesses. Methods: This prospective study involved a sample of 976 children from Kuwait based on mothers’ reporting. Data collection about the vaccination status of children and various health outcomes relevant to chronic and acute illnesses was performed based on structured questionnaires through an online survey. However, participants were classified into unvaccinated (n = 40), partially vaccinated (n = 222), and fully vaccinated (n = 714). Statistical analyses, including the chi-square test, Odds Ratios (OR), 95% Confidence Interval (CI), and logistic regression, were performed using SAS (Version 9.4) to determine the associations between vaccination status and health outcomes among children. Results: The study disclosed that vaccinated children showed an increased diagnosis of chronic (allergic rhinitis, allergies, autism spectrum, eczema, neuro-developmental disorders, learning disability, ADHD, and any chronic condition) and acute (whooping cough, pneumonia, rubella, hepatitis A or B, measles, mumps, meningitis, influenza, rotavirus, cancer, chronic fatigue, Crohn’s disease, inflammatory bowel disease, conduct disorder, diabetes type 1 or 2, rheumatoid arthritis, obesity, seizures, hearing loss, polio, diphtheria, tetanus, and depression) illnesses than unvaccinated children. The fully vaccinated children showed an increased prevalence of influenza diagnosis, while partially vaccinated children were more likely to be diagnosed with rheumatoid arthritis than unvaccinated children. In contrast, unvaccinated were more likely to have been diagnosed with chickenpox and encephalopathy than fully and partially vaccinated. Males with chronic and acute conditions had a lower incidence of allergies and pneumonia, respectively, whereas females had a reduced prevalence of acute illnesses, such as whooping cough, inflammatory bowel disease, and hepatitis A or B among vaccinated (n = 936;combination of partially vaccinated and fully vaccinated) children. Regarding medication use and health service applications, vaccinated children were more likely to use medications for fever, antibiotics, and allergies. In addition, they showed an increased rate of sick visits and emergency visits in the past twelve months. On the other hand, factors like age (2 - 5 years, 6 - 9 years, and 10 - 13 years), birth type (cesarian), and mother suffering during pregnancy (gestational diabetes) were significantly associated with NDD (learning disability, autism spectrum, and attention deficient hyperactivity disorder) in the adjusted analysis. In the interaction model of age and birth type, age (6 - 9 years;OR 5.3, 95% CI: 1.1, 25.3) and mother suffering (gestational diabetes;OR 2.5, 95% CI: 1.2, 5.2) during pregnancy were associated with NDD. Conclusion: The findings of this study showed that there are some cases where the infection rate is higher among the vaccinated compared to unvaccinated children, or there are no significant differences between the two groups in Kuwait. Upon controlling the factors in the interaction model, the age of 6 to 9 years and gestational diabetic mothers during pregnancy were associated with the synergistic increment of odds with NDD. These data findings are recommended to verify a larger and diverse group of samples to optimize the vaccination on health outcomes in Kuwait children. 展开更多
关键词 VACCINATION Partial Vaccination Neurodevelopmental Disorders long-term Health Impacts AUTISM Chronic Conditions Acute Conditions KUWAIT
暂未订购
CUDA‑based GPU‑only computation for efficient tracking simulation of single and multi‑bunch collective effects
7
作者 Keon Hee Kim Eun‑San Kim 《Nuclear Science and Techniques》 2026年第1期61-79,共19页
Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based met... Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based methods,tracking on a single CPU core,or parallelizing the computation across multiple cores via the message passing interface(MPI).Although these approaches work well for single-bunch tracking,scaling them to multiple bunches significantly increases the computational load,which often necessitates the use of a dedicated multi-CPU cluster.To address this challenge,alternative methods leveraging General-Purpose computing on Graphics Processing Units(GPGPU)have been proposed,enabling tracking studies on a standalone desktop personal computer(PC).However,frequent CPU-GPU interactions,including data transfers and synchronization operations during tracking,can introduce communication overheads,potentially reducing the overall effectiveness of GPU-based computations.In this study,we propose a novel approach that eliminates this overhead by performing the entire tracking simulation process exclusively on the GPU,thereby enabling the simultaneous processing of all bunches and their macro-particles.Specifically,we introduce MBTRACK2-CUDA,a Compute Unified Device Architecture(CUDA)ported version of MBTRACK2,which facilitates efficient tracking of single-and multi-bunch collective effects by leveraging the full GPU-resident computation. 展开更多
关键词 Code development GPU computing Collective effects
在线阅读 下载PDF
Chemical composition and pharmacological effects of the Forsythia suspensa
8
作者 Jiayuan Wang Zixuan Che +3 位作者 Yuzheng Xiang Meng Zhang Ying Li Yu Chen 《Asian Journal of Traditional Medicines》 2026年第1期42-57,共16页
The dried fruit of Forsythia suspensa(Oleaceae),also known as Forsythia,is a traditional Chinese medicinal herb known for its heat-clearing and detoxifying properties.It is used to disperse nodules,reduce swelling,rem... The dried fruit of Forsythia suspensa(Oleaceae),also known as Forsythia,is a traditional Chinese medicinal herb known for its heat-clearing and detoxifying properties.It is used to disperse nodules,reduce swelling,remove toxins,clear heat,and alleviate wind-heat syndromes.It also has hepatoprotective,anti-inflammatory,antiviral,antibacterial,anticancer,antioxidant,antiaging,and anti-obesity effects,as well as potential therapeutic effects on Alzheimer’s disease and diabetic nephropathy.It is used to treat scrofula,mastitis,wind-heat common cold,and other ailments.The review summarizes the chemical constituents and pharmacological effects of F.suspensa,aiming to provide a scientific foundation for its future development,research,and clinical utilization. 展开更多
关键词 Forsythia suspensa pharmacological effects chemical constituents
暂未订购
Effects of Ecological Ditch and Wetland in Reducing Farmland Drainage Pollutants in Hetao Irrigation District
9
作者 Zhen HU Qiong LIAO +4 位作者 Xu LI Wei QIAO Xiang ZENG Yongbing HUANG Wei REN 《Asian Agricultural Research》 2026年第1期25-32,共8页
[Objectives]To explore the control mode of farmland drainage pollutants and investigate the effects of ecological ditch and wetland on reducing farmland drainage pollutants in Hetao Irrigation District.[Methods]Based ... [Objectives]To explore the control mode of farmland drainage pollutants and investigate the effects of ecological ditch and wetland on reducing farmland drainage pollutants in Hetao Irrigation District.[Methods]Based on the demonstration construction project of the ecological ditch-constructed wetland system in the Hetao Irrigation District,an experimental study was conducted from July to September 2023 to investigate the interception and purification effects of ecological ditches,constructed wetlands,and the combined ecological ditch-constructed wetland system on farmland drainage pollutants.Key water quality parameters measured included total nitrogen(TN)concentration and total phosphorus(TP)concentration.[Results]Different treatment modes of ecological ditches and constructed wetlands have a certain removal effect on nitrogen and phosphorus pollutants in water bodies.The ecological ditches treated with Astragalus laxmannii,Melilotus officinalis,Medicago sativa,bio-ball substrate,and bio-sheet substrate showed reduction efficiencies for TN and TP of 21.09% and 23.84%,12.06% and 26.67%,20.08% and 34.15%,23.65% and 20.56%,and 19.92% and 25.83%,respectively.The emergent plant area showed reduction efficiencies of 24.28%for TN and 17.89%for TP,while the submerged plant area achieved a reduction efficiency of 10.21%for both TN and TP.Among the different treatment modes,the ecological ditch with M.sativa performed better in TP removal,whereas the bio-ball substrate treatment mode showed higher effectiveness in TN removal.In addition,the emergent plant area exhibited better TP removal performance,while the submerged plant area was more effective in TN removal.The combined system of ecological ditch and constructed wetland achieved removal rates of 37.55% for TN and 11.47% for TP.It effectively facilitates the step-by-step interception and adsorption purification of pollutants,thereby showing significant removal and purification effects on nitrogen and phosphorus contaminants.This contributes to mitigating agricultural non-point source pollution.[Conclusions]The combined ecological ditch-constructed wetland system serves dual functions of agricultural drainage and pollutant interception and purification.It reduces the pollution load of farmland drainage on receiving water bodies to some extent and mitigates agricultural non-point source pollution.Therefore,it is a relatively suitable technology for managing agricultural non-point source pollution in the Hetao Irrigation District. 展开更多
关键词 Ecological DITCH CONSTRUCTED WETLAND POLLUTANT Purification effect HETAO Irrigation District
在线阅读 下载PDF
Calenduloside E produced by Bifidobacterium animalis B960 increases glibenclamide efficacy and alleviates drug-induced adverse effects in a type 2 diabetes model
10
作者 Siyuan Shen Liting Lu +4 位作者 Haiyang Tu Shuaiming Jiang Zeng Zhang Zhe Han Jiachao Zhang 《Science Bulletin》 2026年第3期520-524,共5页
Concerns about the long-term safety and efficacy of glibenclamide(GLIB),a type 2 diabetes mellitus(T2DM)treatment,have been reported[1].Recent evidence indicates the gut microbiota composition significantly affects ho... Concerns about the long-term safety and efficacy of glibenclamide(GLIB),a type 2 diabetes mellitus(T2DM)treatment,have been reported[1].Recent evidence indicates the gut microbiota composition significantly affects host glucose metabolism and drugbioavailability,increasingthe efficacy of T2DM therapy[2].In this context,probiotic-drug coadministration,an emerging adjunct approach for treating metabolic diseases,improves therapeutic outcomes and ameliorates side effects[3]. 展开更多
关键词 treating metabolic diseasesimproves type diabetes mellitus t dm treatmenthave bifidobacterium animalis B adjunct approach calenduloside E glibenclamide efficacy ameliorates side effects drug induced adverse effects
原文传递
An overview of the advantageous effects and underlying mechanisms of natural polysaccharides in inflammatory bowel disease
11
作者 Yating Shao Bo Li +6 位作者 Yongfang Wang Chuanjie Zhou Yunlong Qiao Xinglishang He Shengqiang Tong Guiyuan Lv Suhong Chen 《Chinese Journal of Natural Medicines》 2026年第1期45-58,共14页
Inflammatory bowel disease(IBD),which includes Crohn’s disease(CD)and ulcerative colitis(UC),is a chronic inflammatory condition affecting the gastrointestinal tract.The global incidence and prevalence of IBD continu... Inflammatory bowel disease(IBD),which includes Crohn’s disease(CD)and ulcerative colitis(UC),is a chronic inflammatory condition affecting the gastrointestinal tract.The global incidence and prevalence of IBD continue to increase.While multiple clinical treatments exist,conventional therapies frequently present limitations and adverse effects.Natural polysaccharides(PSs)have emerged as a significant focus of research interest due to their therapeutic potential and applications in functional foods and health products.This review synthesizes current understanding of IBD pathophysiology and the mechanisms by which natural PSs counter IBD,including their capacity to restore immune homeostasis and intestinal barrier function,modulate gut microbiota and metabolites,reduce oxidative stress,and address irregularities in autophagy and endoplasmic reticulum stress(ERS).The review examines the structure-activity relationships of PSs demonstrating anti-IBD effects and identifies promising therapeutic products.The discussion encompasses pharmacokinetics,safety evaluations,and clinical applications of these compounds.This comprehensive review establishes a theoretical foundation for developing natural PS-based therapeutic approaches for IBD management. 展开更多
关键词 Natural polysaccharides Inflammatory bowel disease PATHOGENESIS Therapeutic effect Research progress
原文传递
Research Advances in Pharmacological Effects and Clinical Applications of Rhubarb and Its Compound Formulations in the Treatment of Sepsis
12
作者 Yu CHEN Linna LU +1 位作者 Qingmin XING Lijuan SHEN 《Medicinal Plant》 2026年第1期83-91,共9页
This article reviews the research advances in traditional Chinese medicine rhubarb and its compound formulations in the treatment of sepsis,with particular emphasis on elucidating their mechanisms of action and clinic... This article reviews the research advances in traditional Chinese medicine rhubarb and its compound formulations in the treatment of sepsis,with particular emphasis on elucidating their mechanisms of action and clinical application value.Research has demonstrated that rhubarb and its compound formulations exert therapeutic effects via multiple targets and mechanisms,including anti-inflammatory actions,protection of the intestinal barrier,modulation of immune balance,inhibition of oxidative stress,and regulation of associated signaling pathways.Clinically,rhubarb has shown distinct advantages in enhancing gastrointestinal function,mitigating systemic inflammatory responses,and reducing mortality rates among patients with sepsis.These findings provide a foundational reference for the integrated prevention and treatment of sepsis through the combined use of traditional Chinese and Western medicine. 展开更多
关键词 SEPSIS RHUBARB Traditional Chinese medicine Compound formulation Pharmacological effect Clinical application
暂未订购
Correction models of Reynolds number effects for through-flow method in axial compressors
13
作者 Xiaochen WANG Chunwei GU 《Chinese Journal of Aeronautics》 2026年第1期78-94,共17页
Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages ha... Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages have difficulties in predicting comprehensively Reynolds number effects on airfoils,matching and characteristics curves.This study proposes Re-correction models for loss,deviation angle and endwall blockage based on classical theories and cascade tests,and loss and deviation models show good agreement in test data of NACA65 and C4 cascades.Throughflow method considering Reynolds number effects is developed by integrating the correction models into a verified Streamline Curvature(SLC)tool.A three-stage axial compressor is investigated through SLC and CFD methods from design Reynolds number(Red=2106)to low Re=4104,and the numerical methods are validated with test data of characteristic curves and spanwise distributions at Red.With Re reduction,SLC method with correction models well predicts variation in overall performances compared with CFD calculations and Wassell's model.Streamwise and spanwise matching such as total pressure and loss distributions in SLC predictions are basically consistent with those in CFD results at near-stall points under design and low Reynolds numbers.SLC and CFD methods share similar detections of stall risks in the third stage(Stg3),and their analyses of diffusion processes deviate to some extent due to different predictions in separated endwall flow.The correction models can be adopted to consider Reynolds number effects in through-flow design and analysis of axial compressors. 展开更多
关键词 Axial compressor Reynolds number effects Correction model Through-flow method Aerodynamic performance
原文传递
A comparison of porous sandstone fracturing induced by increasing fluid pressure or decreasing confining pressure:Stress-path and rate-dependence effects
14
作者 Xu Han Lei Wang +2 位作者 Erik Rybacki Marco Bohnhoff Georg Dresen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期151-165,共15页
When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may aff... When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may affect the initiation and propagation of fractures within brittle materials.Understanding the physical mechanisms leading to failure is crucial for underground engineering applications and geo-energy exploration and storage.We conducted triaxial compression experiments on porous Bentheim sandstone samples at different stress paths and pressure change rates.First,at a constant confining pressure of 35 MPa and pore pressure of 5 MPa,intact cylindrical samples were axially loaded up to about 85%of the peak strength.Subsequently,the axial piston position was fixed,and then either the pore pressure was increased or the confining pressure was decreased at two different rates(0.5 MPa/min or 2 MPa/min),leading to final catastrophic failure.The mechanical results revealed that samples subjected to higher rates of decreasing effective confining pressure exhibited larger stress drop rates,higher slip rates,higher total breakdown work,higher rates of acoustic emissions(AEs)before failure,and higher post-failure AE decay rates.In contrast,the applied stress path did not significantly affect rock failure characteristics.Comparison of located AE events with post-mortem microstructures of deformed samples shows a good agreement.The AE source type determined from the P-wave first-motion polarity shows that shear failure dominated the fracture process when approaching failure.Gutenberg-Richter b-values revealed a significant decrease before failure in all tests.Our results indicate that,in contrast to the stress path,the rate of effective stress change strongly affects fracturing behavior and AE rate changes. 展开更多
关键词 Porous sandstone Fluid injection effective confining pressure changing rate Stress path
在线阅读 下载PDF
From ancient herb to modern miracle:an in-depth analysis of the cardioprotective effects of artemisinin and its derivatives
15
作者 Hao-Shuang LI Shu-Rong LI +6 位作者 Wen-Jue LIU Yuan ZHANG Rui WU Xu-Yang CUI Jia-Zheng SUN You-Wei MA Ying ZHAO 《Journal of Geriatric Cardiology》 2026年第1期45-64,共20页
Significant progress has been recently made in studying artemisinin and its derivatives for treating cardiovascular diseases,making this area a prominent research focus.Artemisinin,discovered with great acclaim,was in... Significant progress has been recently made in studying artemisinin and its derivatives for treating cardiovascular diseases,making this area a prominent research focus.Artemisinin,discovered with great acclaim,was initially and widely adopted in antimalarial treatments.As scientific research steadily progressed,its latent potential role in the cardiovascular system gradually captured the attention of the global scientific community.Artemisinin and its derivatives can reportedly play a protective role in the cardiovascular system through various mechanisms,including anti-inflammatory,anti-angiogenic,antioxidant,and anti-fibrotic effects,as well as the regulation of blood lipids and blood pressure.In particular,they have shown promising therapeutic effects in models of cardiovascular diseases such as atherosclerosis,myocardial ischaemia,and cardiac hypertrophy.In addition,artemisinin and its derivatives can improve cardiovascular function and prevent cardiovascular injury by regulating signalling pathways closely related to cardiovascular disease,such as AMPK and NF-kB.Although numerous ex vivo and in vivo experiments have verified the potential role of artemisinin in treating cardiovascular diseases,systematic studies to comprehensively elucidate its specific mechanism of action remain scarce.Further exploration of the precise roles of artemisinin and its derivatives in cardiovascular disease therapy,along with their potential clinical applications,could offer valuable insights for future research and treatment strategies. 展开更多
关键词 antimalarial treatmentsas ARTEMISININ cardiovascular diseasesmaking myocardial ischemia cardiac hypertrophy cardiovascular system cardioprotective effects ATHEROSCLEROSIS
暂未订购
Damage evolution and constitutive model of limestone with horizontal fissure under the coupled effects of dry-wet cycling and precompression stress
16
作者 Shunbo Zhang Zhongping Yang +2 位作者 Yang Gao Miao Liu Shanmeng Hou 《International Journal of Mining Science and Technology》 2026年第1期205-228,共24页
To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests ... To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests were conducted,and a corresponding piecewise damage constitutive model(PDCM)was established.We found that both dry-wet cycling and precompression stress deteriorate the physical properties,alter the microscopic characteristics,and reduce the mechanical properties of the LHF.These degradations are particularly pronounced under the CEDWCPS,although the magnitude of these changes gradually diminishes with the progression of dry-wet cycling.Meanwhile,they also reduce the deformation degree,prolong the micropore compaction stage,shorten the unstable crack propagation stage,lower the frequency and intensity of AE events,decrease the high-amplitude and high-frequency AE signals,enlarge crack scales,and shorten the crack initiation time.Among the changes of these indicators,the dry-wet cycling plays a dominant role.The crack types of LHF under the CEDWCPS(LHFCEDWCPS)are predominantly tensile cracks,supplemented by shear cracks.The failure mode can be defined as tensileshear composite failure.Finally,the established PDCM effectively captures the nonlinear deformation of micropore and the linear deformation of the matrix in LHFCEDWCPS,with all corresponding R^(2) consistently exceeding 0.97. 展开更多
关键词 Dry-wet cycling Precompression stress Coupled effect Fractured limestone Damage evolution Damage constitutive model
在线阅读 下载PDF
Effects of confinedaquifer on water-sand gushing disasters in soft soil
17
作者 Liangjin Li Yafei Qiao +1 位作者 Jinchun Chai Wenqi Ding 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1126-1137,共12页
Water-sand gushing(WSG)disasters in confinedaquifers pose significantchallenges to the utilization of deep underground spaces in soft soil areas.Since few studies have considered the impact of confined aquifer thickne... Water-sand gushing(WSG)disasters in confinedaquifers pose significantchallenges to the utilization of deep underground spaces in soft soil areas.Since few studies have considered the impact of confined aquifer thickness and confinedwater pressure on WSG disasters,a novel visual model test system was developed to investigate the influencingcharacteristics and mechanisms of the two aforementioned factors.The test results showed that the WSG process in clay aquiclude-confinedaquifer composite strata exhibits two prominent stages.First,the sand loss zone expands vertically in an ellipsoid shape.Then,it expands horizontally once the ellipsoid reaches the boundary of the clay layer.The sand loss continues until the overlying clay sinks to the bottom to clog the gushing crack,creating a large sinkhole at the surface.Increasing the confinedaquifer thickness can increase the vertical expansion of the ellipsoid and delay the clay-clogging effects,thereby considerably increasing the severity of sand loss,stratum deformation,and surface settlement.An increase in the confinedwater pressure markedly increases the hydraulic gradient along the seepage path,which contributes to increasing the gushing rates of water and sand.As a result,substantial sand loss occurs before the clay clogs the gushing crack,inducing more cracks and deeper sinkholes at the surface.All the aforementioned results provide insights into the effects of confinedaquifer on WSG disasters in clay aquiclude-confinedaquifer composite strata. 展开更多
关键词 Water-sand gushing(WSG)disasters Confinedaquifer thickness Confinedwater pressure Beam-bearing mechanism Clay-clogging effects Model test
在线阅读 下载PDF
Effects of non-plastic silt and soil aging on re-liquefaction resistance of sandy soils
18
作者 Tadao Enomoto 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1601-1620,共20页
To investigate the influencesof non-plastic silt and soil aging on the re-liquefaction resistance of sands,a series of undrained triaxial tests was performed on sand-silt mixtures with finescontent ranging from 0%to 1... To investigate the influencesof non-plastic silt and soil aging on the re-liquefaction resistance of sands,a series of undrained triaxial tests was performed on sand-silt mixtures with finescontent ranging from 0%to 100%,as well as on undisturbed and reconstituted non-plastic sandy soils retrieved from earth structures with a history of earthquake-induced damage.The specimens on sand-silt mixtures were produced under an initial degree of compaction of 95%.In these tests,liquefaction histories were applied three times to a single specimen under the same cyclic stress ratio after the respective consolidation stages with the measurements of the shear wave velocities.The following conclusions can be obtained from the test results:(1)The liquefaction resistance obtained in the firstto third cyclicloading stages decreased initially with increasing finescontent up to about 45%,while it increased afterward.Therefore,the susceptibility of sands containing a relatively large amount of non-plastic silt to reliquefaction may be more significantthan that of clean sands;(2)The liquefaction resistance and the shear wave velocity decreased significantlyduring the second cyclic-loading stage and after the second consolidation,respectively,despite an increase in the specimen density caused by the first liquefaction history,while they increased in the third stage.The possible reason for this change would be the disturbance of soil structures due to liquefaction,which may be partially evaluated by the volumetric strain during the respective consolidation stages,and the stress-induced anisotropy formed in the previous liquefaction stage;and(3)The liquefaction resistance and the shear wave velocity of the undisturbed specimens,which were measured in the firstto third stages,were larger than those of the reconstituted ones due to the aging effects,respectively.That is,the aging effects may not necessarily be eliminated by the subsequent liquefaction history and may remain partially in some cases. 展开更多
关键词 Multiple liquefaction Non-plastic silt Undisturbed non-plastic sandy soil Aging effect Triaxial liquefaction test Shear wave velocity
在线阅读 下载PDF
Examining the Nonlinear Effects of Urban Population Polycentricity on Carbon Emissions Efficiency Using a Gradient Boosting Decision Tree Model:Evidence from 295 Chinese Cities
19
作者 WANG Cheng YANG Xingzhu 《Chinese Geographical Science》 2026年第2期222-238,共17页
Transforming urban spatial structures to promote green and low-carbon development is an effective strategy.Although prior studies have examined the impact of urban polycentricity on carbon emissions and economic devel... Transforming urban spatial structures to promote green and low-carbon development is an effective strategy.Although prior studies have examined the impact of urban polycentricity on carbon emissions and economic development,research on its role in the synergistic relationship between these factors regarding carbon emission efficiency is limited.Furthermore,existing literature often overlooks nonlinear effects and interactions with other urban variables.This paper analyzed data from 295 Chinese cities in 2020,calculating urban population polycentricity,population dispersion indices,and carbon emission efficiency.Utilizing local spatial autocorrelation tools,we reveal interactions among urban population polycentricity,dispersion,carbon emissions,and carbon emission efficiency.We then employ a gradient boosting decision tree model(GBDT)to explore nonlinear and synergistic effects of polycentric urbanization.Key findings include:1)polycentric urbanization in Chinese cities exhibits significant spatial differentiation characteristics.The Polycentricity index is relatively high in economically developed eastern coastal regions with an overall low level,carbon emissions are concentrated in industrialized north-central cities and some Yangtze River Delta hubs,and carbon emission efficiency is the highest in the Yangtze River Delta while relatively low in Northeast China;there are significant spatially heterogeneous interaction characteristics among population polycentricity,population dispersion,carbon emissions,and carbon emission efficiency.2)Urban population polycentricity contributes 9.42%to total carbon emissions and 6.24%to carbon emission efficiency.3)The polycentricity index has a nonlinear impact on carbon emissions and carbon emission efficiency:no significant effect when below 0.50 or above 0.55,increased carbon emissions in 0.50-0.53,and reduced carbon emissions with improved efficiency in 0.53-0.55.4)The polycentricity index has an interaction effect with other variables;specifically,when the polycentricity index is between 0.53 and 0.55,its interaction with urban gross domestic product(GDP),urban population,urban built-up area,green coverage rate in built-up areas,urban technological expenditure,and the proportion of the output value of the secondary industry will reduce carbon emissions and improve carbon emission efficiency.These findings enhance the understanding of urban spatial structures and carbon emissions,providing valuable insights for policymakers in developing green and low-carbon strategies. 展开更多
关键词 urban polycentricity carbon emission efficiency gradient boosting decision tree(GBDT) nonlinear threshold effects Chinese cities
在线阅读 下载PDF
Lithium Nitrate Effects for Lithium-Based Chemical Batteries:A Review
20
作者 Xianshu Wang Junru Wu +6 位作者 Huirong Wang Xiangshao Yin Zhuo Zhou Yuanyuan Huang Yelong Zhang Weishan Li Baohua Li 《Carbon Energy》 2026年第1期197-222,共26页
Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and l... Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and long-range electric vehicles.However,technical barriers such as dendrite growth and poor Li plating/stripping reversibility severely hinder the practical application of LMBs.However,lithium nitrate(LiNO_(3))is found to be able to stabilize the Li/electrolyte interface and has been used to address the above challenges.To date,considerable research efforts have been devoted toward understanding the roles of LiNO_(3) in regulating the surface properties of Li anodes and toward the development of many effective strategies.These research efforts are partially mentioned in some articles on LMBs and yet have not been reviewed systematically.To fill this gap,we discuss the recent advances in fundamental and technological research on LiNO_(3) and its derivatives for improving the performances of LMBs,particularly for Li-sulfur(S),Li-oxygen(O),and Li-Li-containing transition-metal oxide(LTMO)batteries,as well as LiNO_(3)-containing recipes for precursors in battery materials and interphase fabrication.This review pays attention to the effects of LiNO_(3) in lithium-based batteries,aiming to provide scientific guidance for the optimization of electrode/electrolyte interfaces and enrich the design of advanced LMBs. 展开更多
关键词 effects and mechanisms LiNO_(3)derivatives LiNO_(3)-containing recipes lithium metal anode Lithium nitrate basis lithium-based chemical batteries
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部