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Association between Residential Greenness and Cardiometabolic Risk Factors among Adults in Rural Xinjiang Uygur Autonomous Region,China:A Cross-Sectional Study
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作者 Leyao Jian Bo Yang +10 位作者 Rulin Ma Shuxia Guo Jia He Yu Li Yusong Ding Dongsheng Rui Yidan Mao Xin He Xueying Sun Shengyu Liao Heng Guo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第10期1184-1194,共11页
Objective This study aimed to explore the relationships between residential greenness and cardiometabolic risk factors among rural adults in Xinjiang Uygur Autonomous Region(Xinjiang)and thus provide a theoretical bas... Objective This study aimed to explore the relationships between residential greenness and cardiometabolic risk factors among rural adults in Xinjiang Uygur Autonomous Region(Xinjiang)and thus provide a theoretical basis and data support for improving the health of residents in this region.Methods We recruited 9,723 adult rural residents from the 51st Regiment of the Third Division of the Xinjiang Production and Construction Corps in September 2016.The normalized difference vegetation index(NDVI)was used to estimate residential greenness.The generalized linear mixed model(GLMM)was used to examine the association between residential greenness and cardiometabolic risk factors.Results Higher residential greenness was associated with lower cardiometabolic risk factor prevalence.After adjustments were made for age,sex,education,and marital status,for each interquartile range(IQR)increase of NDVI500-m,the risk of hypertension was reduced by 10.3%(OR=0.897,95%CI=0.836-0.962),the risk of obesity by 20.5%(OR=0.795,95%CI=0.695-0.910),the risk of type 2 diabetes by 15.1%(OR=0.849,95%CI=0.740-0.974),and the risk of dyslipidemia by 10.5%(OR=0.895,95%CI=0.825-0.971).Risk factor aggregation was reduced by 20.4%(OR=0.796,95%CI=0.716-0.885)for the same.Stratified analysis showed that NDVI500-m was associated more strongly with hypertension,dyslipidemia,and risk factor aggregation among male participants.The association of NDVI500-m with type 2 diabetes was stronger among participants with a higher education level.PM10 and physical activity mediated 1.9%-9.2%of the associations between NDVI500-m and obesity,dyslipidemia,and risk factor aggregation.Conclusion Higher residential greenness has a protective effect against cardiometabolic risk factors among rural residents in Xinjiang.Increasing the area of green space around residences is an effective measure to reduce the burden of cardiometabolic-related diseases among rural residents in Xinjiang. 展开更多
关键词 Green space Cardiometabolic risk factors cross-sectional study Rural adults
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A Cross-Sectional Study on The Prevalence of Anemia in Maintenance Hemodialysis and Peritoneal Dialysis Patients and Its Related Factors
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作者 Mingrong Huang 《Journal of Clinical and Nursing Research》 2024年第3期134-140,共7页
Objective:To study the prevalence of anemia,the proportion of hemoglobin(Hb)levels,the treatment methods,and the influencing factors of Hb levels in maintenance hemodialysis(MHD)and peritoneal dialysis patients.Method... Objective:To study the prevalence of anemia,the proportion of hemoglobin(Hb)levels,the treatment methods,and the influencing factors of Hb levels in maintenance hemodialysis(MHD)and peritoneal dialysis patients.Methods:In this study,602 patients with maintenance hemodialysis and continuous ambulatory peritoneal dialysis were enrolled from December 2020 to December 2022 in our hospital,and their medical records were collected and summarized.The main contents included the patient’s gender,age,primary disease,dialysis duration,dialysis method,the use of erythropoietic stimulating agents(ESA),intravenous iron,and laboratory tests.A Hb index exceeding 110 g/L was set as the standard for the prevalence of anemia.Results:The rate of anemia in patients undergoing blood purification was 83%.The proportion of ESA use was 84.1%,and the proportion of iron use was 76.7%,of which the proportion of intravenous iron used was 17.0%,and the proportion of folic acid used was 28.3%.Conclusion:The incidence of anemia in MHD patients was relatively high,with a low proportion of patients reaching the standard Hb levels.Risk factors include albumin(ALB)levels,iron storage,white blood cells,C-reactive protein,cholesterol,etc.Nutritional support,iron supplementation,and prevention of micro-inflammatory reactions can effectively promote the improvement of Hb indicators in dialysis patients to prevent anemia. 展开更多
关键词 HEMODIALYSIS Peritoneal dialysis ANEMIA Related factors cross-sectional study
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Factors Affecting Patient Satisfaction with Community Health Service under the Gatekeeper System:A Cross-sectional Study in Nanjing,China 被引量:3
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作者 LI Wen Zhen GAN Yong +6 位作者 ZHOU Yan Feng CHEN Ya Wen LI Jing KKANDAWIRE Naomiem HU Sai QIAO Yan LU Zu Xun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第9期685-690,共6页
The gatekeeper policy has been implemented for approximately ten years on a pilot population in China. It is necessary to assess the satisfaction of patients utilizing community health service(CHS) under the gatekee... The gatekeeper policy has been implemented for approximately ten years on a pilot population in China. It is necessary to assess the satisfaction of patients utilizing community health service(CHS) under the gatekeeper system. Our study showed that the cognition of gatekeeper policy was associated with four dimensions including doctor‐patient relationships, information and support, organization of care, and accessibility(P 〈 0.001). One or more factors such as gender and self‐perceived health scores also affected their satisfaction. General practitioners must be prepared to focus on these aspects of information and support, organization of care, and accessibility as indicators of potential opportunities for improvement. Additionally, policymakers can improve patients' satisfaction with CHS by strengthening their awareness of the gatekeeper policy. 展开更多
关键词 CHS A cross-sectional Study in Nanjing China factors Affecting Patient Satisfaction with Community Health Service under the Gatekeeper System
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Systemic Inflammation Response Index and weight loss as prognostic factors in metastatic pancreatic cancer: A concept study from the PANTHEIA-SEOM trial
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作者 Vilma Pacheco-Barcia Sara Custodio-Cabello +7 位作者 Fatima Carrasco-Valero Magda Palka-Kotlowska Axel Mariño-Mendez Alberto Carmona-Bayonas Javier Gallego A J Muñoz Martín Paula Jimenez-Fonseca Luis Cabezon-Gutierrez 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期386-397,共12页
BACKGROUND The prognostic value of the Systemic Inflammation Response Index(SIRI)in advanced pancreatic cancer is recognized,but its correlation with patients´nutritional status and outcomes remains unexplored.AI... BACKGROUND The prognostic value of the Systemic Inflammation Response Index(SIRI)in advanced pancreatic cancer is recognized,but its correlation with patients´nutritional status and outcomes remains unexplored.AIM To study the prognostic significance of SIRI and weight loss in metastatic pancreatic cancer.METHODS The PANTHEIA-Spanish Society of Medical Oncology(SEOM)study is a multicentric(16 Spanish hospitals),observational,longitudinal,non-interventional initiative,promoted by the SEOM Real World-Evidence work group.This pilot study sought to analyze the association between weight loss and inflammatory status as defined by SIRI.The cohort stems from a proof-of-concept pilot study conducted at one of the coordinating centers.Patients with pathologically confirmed metastatic pancreatic adenocarcinoma,treated from January 2020 to January 2023,were included.The index was calculated using the product of neutrophil and monocyte counts,divided by lymphocyte counts,obtained within 15 days before initiation chemotherapy.This study evaluated associations between overall survival(OS),SIRI and weight loss.RESULTS A total of 50 patients were included.66%of these patients were male and the median age was 66 years.Metastasis sites:36%liver,12%peritoneal carcinomatosis,10%lung,and 42%multiple locations.Regarding the first line palliative chemotherapy treatments:50%received gemcitabine plus nab-paclitaxel;28%,modified fluorouracil,leucovorin,irinotecan and oxaliplatin,and 16%were administered gemcitabine.42%had a weight loss>5%in the three months(mo)preceding diagnosis.21 patients with a SIRI≥2.3×10^(3)/L exhibited a trend towards a lower median OS compared to those with a SIRI<2.3×10^(3)/L(4 vs 18 mo;P<0.000).Among 21 patients with>5%weight loss before diagnosis,the median OS was 6 mo,in contrast to 19 mo for those who did not experience such weight loss(P=0.003).Patients with a weight loss>5%showed higher SIRI levels.This difference was statistically significant(P<0.000).For patients with a SIRI<2.3×10^(3)/L,those who did not lose>5%of their weight had an OS of 20 mo,compared to 11 mo for those who did(P<0.001).No association was found between carbohydrate antigen 19-9 levels≥1000 U/mL and weight loss.CONCLUSION A higher SIRI was correlated with decreased survival rates in patients with metastatic pancreatic cancer and associated with weight loss.An elevated SIRI is suggested as a predictor of survival,emphasizing the need for prospective validation in the upcoming PANTHEIA-SEOM study. 展开更多
关键词 Pancreatic cancer NUTRITION Prognostic factor INFLAMMATION Advanced cancer Systemic inflammatory response index Weight loss
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Prevalence of diarrhea and associated risk factors among children under-five years of age in Eastern Ethiopia: A cross-sectional study 被引量:2
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作者 Bezatu Mengistie Yemane Berhane Alemayehu Worku 《Open Journal of Preventive Medicine》 2013年第7期446-453,共8页
Diarrhea remains a major cause of mortality in children under 5 years of age in Sub-Saharan countries in Africa. Risk factors for diarrhea vary by context and have important implications for developing appropriate str... Diarrhea remains a major cause of mortality in children under 5 years of age in Sub-Saharan countries in Africa. Risk factors for diarrhea vary by context and have important implications for developing appropriate strategies to reduce the burden of the disease. The objective of this study was to assess the prevalence of diarrhea and associated risk factors among children un-der 5 years of age in Kersa district, located in Eastern Ethiopia. A community-based cross-sectional study was conducted among 1456 randomly selected households with at least one child under 5 years of age. A questionnaire and an observational check list were used for col-lecting information on socio-economic charac-teristics, environmental hygiene and behavioral practices, and occurrence of diarrhea among children under 5 years of age. Logistic regres-sion was used to calculate the adjusted odds ratio of 95% confidence interval. The two-week prevalence of diarrhea among children under 5 years of age was 22.5% (95% CI: 20.3-24.6). Improper refuse disposal practices (OR = 2.22, 95% CI: 1.20-4.03), lack of hand washing facilities (OR = 1.92, 95%CI: 1.29-2.86), living in rural area (OR = 1.81, 95% CI: 1.12-3.31), the presence of two or more siblings in a household (OR = 1.74, 95% CI: 1.33-2.28), and age of the child (OR= 2.25, 95% CI;1.5-3.36) were the major risk factors for diarrhea. This study demonstrated that diarrhea morbidity was relatively high among children under 5 years of age residing in Eastern Ethiopia. Efforts to reduce childhood diarrhea should focus on improving household sanitation, personal hygiene, and child birth spacing. 展开更多
关键词 DIARRHEA Risk factor CHILDREN under 5 YEARS Ethiopia cross-sectionAL Study HYGIENE
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Nurses' perception of risk factors for infusion phlebitis:A cross-sectional survey 被引量:1
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作者 Xiang-Feng Li Wei Liu Ying Qin 《Chinese Nursing Research》 CAS 2016年第1期37-40,共4页
Objective: The aim of the present study was to investigate Chinese nurses' perception of risk factors for phlebitis. Methods: A convenience sample of hospital nurses was recruited in Beijing, China. Data were colle... Objective: The aim of the present study was to investigate Chinese nurses' perception of risk factors for phlebitis. Methods: A convenience sample of hospital nurses was recruited in Beijing, China. Data were collected using a demographic information questionnaire and a questionnaire measuring nurses' perception of risk factors for infusion phlebitis. Results: It was found that knowledge of risk factors for infusion phlebitis was incomplete, even among experienced nurses in the study participants. A high rate of incorrect answers to questions about the [oH of fluid (89.9%), gauze or polyurethane catheter dressings (79.1%), and steel needles for drug infusion (76.3%) was observed. Conclusions: These findings suggest that nurses should be trained about the risk factors for infusion phlebitis. 展开更多
关键词 cross-sectional surveyNursesPerceptionPhlebitisRisk factors
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Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology
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作者 Yiyang Qin Wenzhen Zhu +6 位作者 Tingting Guo Yiran Zhang Tingting Xing Peng Yin Shihua Li Xiao-Jiang Li Su Yang 《Neural Regeneration Research》 SCIE CAS 2025年第9期2655-2666,共12页
Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen r... Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy patients.These aggregates alter protein-protein interactions and compromise transcriptional activity.In this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic factor.Overexpressio n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor aggregation.Conversely.knocking down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor aggregation.Our findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy. 展开更多
关键词 androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model NEURODEGENERATION neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor
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Current Status and Risk Factors of Kinesiophobia in Patients with Temporomandibular Disorders in Tianjin,China:a Cross-Sectional Study
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作者 Qi Zhang 《Psychosomatic Medicine Research》 2022年第1期1-7,共7页
Objective:To investigate the current status of kinesiophobia in patients with temporomandibular disorders(TMD)and analyze its risk factors.Methods:The Tampa Scale for kinesiophobia for patients with Temporomandibular ... Objective:To investigate the current status of kinesiophobia in patients with temporomandibular disorders(TMD)and analyze its risk factors.Methods:The Tampa Scale for kinesiophobia for patients with Temporomandibular Disorders(TSK-TMD),Numerical Rating Scale(NRS),Hospital Anxiety and Depression Scale(HADS),General Self-Efficacy Scale(GSES),Simplified Coping Style Questionnaire(SCSQ),and Social Support Rating Scale(SSRS)were adopted to measure patient's kinesiophobia,pain intensity,anxiety,depression,self-efficacy,coping styles and social support.Multiple linear regression was used to analyze the risk factors of kinesiophobia in patients with TMD.Results:A total of 307 participants were included in the present study.The average score of patients with kinesiophobia was(34.37±6.96)points.Multiple linear regression analysis showed that pain duration,worst pain intensity,mouth opening limitation,joint noise,joint trauma,self-efficacy,depression,negative coping style,support utilization and education level are independent risk factors for kinesiophobia.Conclusion:Patients with TMD have higher levels of kinesiophobia and poor recognition of the disease.Longer pain duration,pain intensity,mouth opening limitation,joint noise,joint trauma,lower self-efficacy,depression,negative coping style,lower support utilization and lower educational level can be used to predict the degree of kinesiophobia. 展开更多
关键词 KINESIOPHOBIA Risk factors cross-sectional study Temporomandibular disorders
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Activation of hypoxia-inducible factor 1 attenuates periapical inflammation and bone loss 被引量:23
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作者 Kimito Hirai Hisako Furusho +1 位作者 Kiichi Hirota Hajime Sasaki 《International Journal of Oral Science》 SCIE CAS CSCD 2018年第2期92-101,共10页
Hypoxia(low oxygen level) is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation... Hypoxia(low oxygen level) is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation of hypoxia-inducible factor 1(HIF-1).Hypoxia interferes degradation of HIF-1 alpha subunit(HIF-1α), leading to stabilisation of HIF-1α, heterodimerization with HIF-1 beta subunit(HIF-1β) and subsequent activation of HIF-1 pathway. Apical periodontitis(periapical lesion) is a consequence of endodontic infection and ultimately results in destruction of tooth-supporting tissue, including alveolar bone. Thus far, the role of HIF-1 in periapical lesions has not been systematically examined. In the present study, we determined the role of HIF-1 in a wellcharacterised mouse periapical lesion model using two HIF-1α-activating strategies, dimethyloxalylglycine(DMOG) and adenovirusinduced constitutively active HIF-1α(CA-HIF1 A). Both DMOG and CA-HIF1 A attenuated periapical inflammation and tissue destruction. The attenuation in vivo was associated with downregulation of nuclear factor-κappa B(NF-κB) and osteoclastic gene expressions. These two agents also suppressed NF-κB activation and subsequent production of proinflammatory cytokines by macrophages. Furthermore, activation of HIF-1α by DMOG specifically suppressed lipopolysaccharide-stimulated macrophage differentiation into M1 cells, increasing the ratio of M2 macrophages against M1 cells. Taken together, our data indicated that activation of HIF-1 plays a protective role in the development of apical periodontitis via downregulation of NF-κB, proinflammatory cytokines, M1 macrophages and osteoclastogenesis. 展开更多
关键词 CA Activation hypoxia-inducible factor attenuates periapical inflammation bone loss HIF
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Dynamic caustics test of blast load impact on neighboring different cross-section roadways 被引量:6
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作者 Guo Dongming Zhou Baowei +2 位作者 Liu Kang Yang Renshu Yan Pengyang 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期803-808,共6页
Using digital laser dynamic caustics experimental system and conducting simulation experiment researched the influence rule of blasting excavation of a new roadway on neighboring existed different cross-section roadwa... Using digital laser dynamic caustics experimental system and conducting simulation experiment researched the influence rule of blasting excavation of a new roadway on neighboring existed different cross-section roadways. The experimental results show that the influence of blast load on adjacent roadway has a good relationship with the cross-section of roadway. The expansion distance of precrack existed in circular, arch-wall, rectangular roadway is respectively 1.76, 1.61 and 0 cm under blast load.At the same time, the direct-blast side of rectangular roadway has more obvious damage compared with circular and arch-wall roadway. It explains that plane reflects more stress wave than arc, so that it exerts more tensile failure in the direct-blast side, which leads to less stress wave diffracting to the precrack in the back-blast side. When the precrack extends, higher value dynamic stress intensity factor in circular roadway works longer than that of arch-wall roadway. Indirectly, it explains that plane's weakening function on stress wave is significantly stronger than arc. Stress wave brings about self-evident influence on the upper and bottom endpoints of the rectangular roadway, and it respectively extends 1.03, 2.06 cm along the line link direction of the center of the blasthole and the upper and bottom endpoints on the right wall. 展开更多
关键词 Dynamic caustics Blast load Different cross-section roadways Precrack Dynamic stress intensity factor
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Evaluation of C and P Factors in Universal Soil Loss Equation on Trapping Sediment: Case Study of Santubong River 被引量:3
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作者 Kelvin K. K. Kuok Darrien Y. S. Mah P. C. Chiu 《Journal of Water Resource and Protection》 2013年第12期1149-1154,共6页
Universal Soil Loss Equation (USLE) is the most comprehensive technique available to predict the long term average annual rate of erosion on a field slope. USLE was governed by five factors include soil erodibility fa... Universal Soil Loss Equation (USLE) is the most comprehensive technique available to predict the long term average annual rate of erosion on a field slope. USLE was governed by five factors include soil erodibility factor (K), rainfall and runoff erodibility index (R), crop/vegetation and management factor (C), support practice factor (P) and slope length-gradient factor (LS). In the past, K, R and LS factors are extensively studied. But the impacts of factors C and P to outfall Total Suspended Solid (TSS) and % reduction of TSS are not fully studied yet. Therefore, this study employs Buffer Zone Calculator as a tool to determine the sediment removal efficiency for different C and P factors. The selected study areas are Santubong River, Kuching, Sarawak. Results show that the outfall TSS is increasing with the increase of C values. The most effective and efficient land use for reducing TSS among 17 land uses investigated is found to be forest with undergrowth, followed by mixed dipt. forest, forest with no undergrowth, cultivated grass, logging 30, logging 10^6, wet rice, new shifting agriculture, oil palm, rubber, cocoa, coffee, tea and lastly settlement/cleared land. Besides, results also indicate that the % reduction of TSS is increasing with the decrease of P factor. The most effective support practice to reduce the outfall TSS is found to be terracing, followed by contour-strip cropping, contouring and lastly not implementing any soil conservation practice. 展开更多
关键词 Universal Soil loss Equation Crop/Vegetation and Management factor (C) Support Practice factor (P) OUTFALL TOTAL Suspended SOLID % Reduction of TOTAL Suspended SOLID
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New Resolution to Coupling Loss Factor of Beam Plate Structure
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作者 刘景泉 姚德源 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期267-272,共6页
The transmission of transverse vibrational energy of a vertically rigid beam plate coupled structure is analyzed to get the theoretical results of coupling loss factor(CLF), a very important parameter in statistical ... The transmission of transverse vibrational energy of a vertically rigid beam plate coupled structure is analyzed to get the theoretical results of coupling loss factor(CLF), a very important parameter in statistical energy analysis(SEA). The modal analysis method is used to discuss the vibration energy of the typical model, as well as the power flow between the two subsystems. Furthermore, the resolution to the coupling loss factor is also derived and compared with the measured values. The analytical results of the coupling loss factor agree with the measured ones fully, this new resolution is significant for the application of SEA. 展开更多
关键词 statistical energy analysis coupling loss factor modal analysis method
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Power Transformer No-Load Loss Prediction with FEM Modeling and Building Factor Optimization 被引量:2
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作者 Ehsan Hajipour Pooya Rezaei +1 位作者 Mehdi Vakilian Mohsen Ghafouri 《Journal of Electromagnetic Analysis and Applications》 2011年第10期430-438,共9页
Estimation of power transformer no-load loss is a critical issue in the design of distribution transformers. Any deviation in estimation of the core losses during the design stage can lead to a financial penalty for t... Estimation of power transformer no-load loss is a critical issue in the design of distribution transformers. Any deviation in estimation of the core losses during the design stage can lead to a financial penalty for the transformer manufacturer. In this paper an effective and novel method is proposed to determine all components of the iron core losses applying a combination of the empirical and numerical techniques. In this method at the first stage all computable components of the core losses are calculated, using Finite Element Method (FEM) modeling and analysis of the transformer iron core. This method takes into account magnetic sheets anisotropy, joint losses and stacking holes. Next, a Quadratic Programming (QP) optimization technique is employed to estimate the incomputable components of the core losses. This method provides a chance for improvement of the core loss estimation over the time when more measured data become available. The optimization process handles the singular deviations caused by different manufacturing machineries and labor during the transformer manufacturing and overhaul process. Therefore, application of this method enables different companies to obtain different results for the same designs and materials employed, using their historical data. Effectiveness of this method is verified by inspection of 54 full size distribution transformer measurement data. 展开更多
关键词 BUILDING factor CORE lossES FINITE ELEMENT Method Power Transformer
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Panel data models with cross-sectional dependence: a selective review 被引量:1
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作者 XU Qiu-hua CAI Zong-wu FANG Ying 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第2期127-147,共21页
In this review, we highlight some recent methodological and theoretical develop- ments in estimation and testing of large panel data models with cross-sectional dependence. The paper begins with a discussion of issues... In this review, we highlight some recent methodological and theoretical develop- ments in estimation and testing of large panel data models with cross-sectional dependence. The paper begins with a discussion of issues of cross-sectional dependence, and introduces the concepts of weak and strong cross-sectional dependence. Then, the main attention is primarily paid to spatial and factor approaches for modeling cross-sectional dependence for both linear and nonlinear (nonparametric and semiparametric) panel data models. Finally, we conclude with some speculations on future research directions. 展开更多
关键词 Panel data models cross-sectional dependence Spatial dependence Interactive fixed effects Common factors.
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Platelet factor 4 induces bone loss by inhibiting the integrinα5-FAK-ERK pathway 被引量:1
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作者 Wei Li Qiwei Zhang +2 位作者 Ranli Gu Lijun Zeng Hao Liu 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第6期573-584,共12页
Background:The effect of platelet factor 4(PF4)on bone marrow mesenchymal stem cells(BMMSCs)and osteoporosis is poorly understood.Therefore,this study aimed to evaluate the effects of PF4-triggered bone destruction in... Background:The effect of platelet factor 4(PF4)on bone marrow mesenchymal stem cells(BMMSCs)and osteoporosis is poorly understood.Therefore,this study aimed to evaluate the effects of PF4-triggered bone destruction in mice and determine the underlying mechanism.Methods:First,in vitro cell proliferation and cell cycle of BMMSCs were assessed using a CCK8 assay and flow cytometry,respectively.Osteogenic differentiation was confirmed using staining and quantification of alkaline phosphatase and Alizarin Red S.Next,an osteoporotic mouse model was established by performing bilateral ovariectomy(OVX).Furthermore,the PF4 concentrations were obtained using enzymelinked immunosorbent assay.The bone microarchitecture of the femur was evaluated using microCT and histological analyses.Finally,the key regulators of osteogenesis and pathways were investigated using quantitative real-time polymerase chain reaction and Western blotting.Results:Human PF4 widely and moderately decreased the cell proliferation and osteogenic differentiation ability of BMMSCs.Furthermore,the levels of PF4 in the serum and bone marrow were generally increased,whereas bone microarchitecture deteriorated due to OVX.Moreover,in vivo mouse PF4 supplementation triggered bone deterioration of the femur.In addition,several key regulators of osteogenesis were downregulated,and the integrinα5-focal adhesion kinase-extracellular signalregulated kinase(ITGA5-FAK-ERK)pathway was inhibited due to PF4 supplementation.Conclusions:PF4 may be attributed to OVX-i nduced bone loss triggered by the suppression of bone formation in vivo and alleviate BMMSC osteogenic differentiation by inhibiting the ITGA5-FAK-ERK pathway. 展开更多
关键词 bone loss bone marrow mesenchymal stem cells integrinα5 OSTEOGENESIS platelet factor 4
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Loss Factors and their Effect on Resonance Peaks in Mechanical Systems 被引量:1
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作者 Roman Vinokur 《Sound & Vibration》 EI 2023年第1期1-13,共13页
The loss factors and their effects on the magnitude and frequency of resonance peaks in various mechanical sys-tems are reviewed for acoustic,vibration,and vibration fatigue applications.The main trends and relationsh... The loss factors and their effects on the magnitude and frequency of resonance peaks in various mechanical sys-tems are reviewed for acoustic,vibration,and vibration fatigue applications.The main trends and relationships were obtained for linear mechanical models with hysteresis damping.The well-known features(complex module of elasticity,total loss factor,etc.)are clarified for practical engineers and students,and new results are presented(in particular,for 2-DOF in-series models with hysteresis friction).The results are of both educational and prac-tical interest and may be applied for NVH analysis and testing,mechanical and aeromechanical design,and noise and vibration control in buildings. 展开更多
关键词 Mechanical loss factor resonance peak ACOUSTICS VIBRATION structural failure noise NVH engineering systems
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Simulation of higher order modes and loss factor of a new type of 500-MHz single cell superconducting cavity at SSRF 被引量:2
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作者 YU Haibo LIU Jianfei +5 位作者 HOU Hongtao LU Changwang WEI Yelong MA Zhenyu FENG Ziqiang MAO Dongqing 《Nuclear Science and Techniques》 SCIE CAS CSCD 2011年第5期257-260,共4页
In this paper,higher order modes(HOMs) and loss factor of a new type of 500-MHz superconducting cavity is studied,by simulating its broadband HOMs damping at different positions of the ferrite HOM-absorber and differe... In this paper,higher order modes(HOMs) and loss factor of a new type of 500-MHz superconducting cavity is studied,by simulating its broadband HOMs damping at different positions of the ferrite HOM-absorber and different lengths of the ferrite.The results show that the impedance and Q value of the HOMs in transverse and longitudinal modes could be greatly reduced.The HOM longitudinal impedance could be damped to meet the requirement of SSRF beam instability threshold.The calculated loss factor of the new SC cavity was compared with cavities at SSRF.It was estimated that the HOM absorber could absorb a total power of 3.16 kW at 4-mm beam bunch length. 展开更多
关键词 损耗因子 高阶模 超导腔 光源 上海 模拟 单细胞 纵向阻抗
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Factor value determination and applicability evaluation of universal soil loss equation in granite gneiss region
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作者 Wen-hai ZHANG Xing-nan ZHANG Zhi-dong GAO 《Water Science and Engineering》 EI CAS 2009年第2期87-97,共11页
Six types of runoff plots were set up and an experimental study was carried out to examine natural rate of soil and water loss in the granite gneiss region of northern Jiangsu Province in China. Through correlation an... Six types of runoff plots were set up and an experimental study was carried out to examine natural rate of soil and water loss in the granite gneiss region of northern Jiangsu Province in China. Through correlation analysis of runoff and soil loss during 364 rainfall events, a simplified and convenient mathematical formula suitable for calculating the rainfall erosivity factor (R) for the local region was established. Other factors of the universal soil loss equation (USLE model) were also determined. Relative error analysis of the soil loss of various plots calculated by the USLE model on the basis of the observed values showed that the relative error ranged from -3.5% to 9.9% and the confidence level was more than 90%. In addition, the relative error was 5.64% for the terraced field and 12.36% for the sloping field in the practical application. Thus, the confidence level was above 87.64%. These results provide a scientific basis for forecasting and monitoring soil and water loss, for comprehensive management of small watersheds, and for soil and water conservation planning in the region. 展开更多
关键词 granite gneiss region soil erosion universal soil loss equation factor value applicability evaluation
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Analysis on the Influence Factors of Capacitor Voltage Transformer Dielectric Loss Measurement
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作者 Yongdong Li Qing-da Meng +3 位作者 Po Yang Zheyuan Zhao Wei Zhang Zhuo Pan 《Energy and Power Engineering》 2013年第4期1240-1242,共3页
Capacitor voltage transformer (CVT), which is with simple structure, convenient maintenance, functional diversity and high impact pressure strength, is widely used. And its capacitance and dielectric loss Angle measur... Capacitor voltage transformer (CVT), which is with simple structure, convenient maintenance, functional diversity and high impact pressure strength, is widely used. And its capacitance and dielectric loss Angle measurement is an important test on testing the insulation of the equipment. This paper is mainly to introduce and discuss one of the CVT test methods——the “self excitation method”, combined with the actual situation encountered in the work, sums up and expounds the maintenance of CVT and preventive test of influence factors. 展开更多
关键词 Capacitive VOLTAGE TRANSFORMER DIELECTRIC loss the Influencing factorS
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Association between knowledge and risk for cardiovascular disease among older adults: A cross-sectional study in China
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作者 Qi Liu Yan-Jin Huang +5 位作者 Ling Zhao Wen Wang Shan Liu Guo-Ping He Li Liao Ying Zeng 《International Journal of Nursing Sciences》 CSCD 2020年第2期184-190,共7页
Objectives:This study aimed to describe cardiovascular risk and cardiovascular disease(CVD)knowledge among older adults,and further explore the association between knowledge and risk.Methods:In this cross-sectional st... Objectives:This study aimed to describe cardiovascular risk and cardiovascular disease(CVD)knowledge among older adults,and further explore the association between knowledge and risk.Methods:In this cross-sectional study,we enrolled 1120 older adults who received physical examination in health centers.The participants were interviewed to obtain their behavioral risk factors related to CVD and clinical characteristics.A risk prediction chart was used to predict participants'cardiovascular risk based on clinical characteristics and behavioral risk factors.Participants'CVD knowledge was collected with a pretested knowledge questionnaire.Results:Among the 1120 participants,240(21.4%)had low cardiovascular risk,353(31.5%)had moderate cardiovascular risk,527(47%)had high and very high cardiovascular risk.The knowledge level about CVD among 0.8%of the 1120 participants was good while that of 56.9%was poor.Lower CVD knowledge level,older age,lower income,and lower educational level were the independent factors of higher cardiovascular risk level.Conclusions:This study highlights the need to reduce the cardiovascular risk among older adults.CVD knowledge should be considered when developing health interventions. 展开更多
关键词 Aged cross-sectional studies Cardiovascular diseases KNOWLEDGE Physical examination Risk factors Surveys and questionnaires
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