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Cross-sectional study of the association between triglyceride glucose-body mass index and obstructive sleep apnea risk
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作者 Li Gong Ming Su +9 位作者 Jing-Han Xu Zhen-Fei Peng Lin Du Ze-Yao Chen Yu-Zhou Liu Lu-Cia Chan Yin-Luan Huang Yu-Tian Chen Feng-Yi Huang Chun-Li Piao 《World Journal of Diabetes》 2025年第3期65-75,共11页
BACKGROUND The triglyceride glucose-body mass index(TyG-BMI)is a novel indicator of insulin resistance(IR).Obstructive sleep apnea(OSA)is a prevalent disorder characterized by recurrent complete or partial collapse of... BACKGROUND The triglyceride glucose-body mass index(TyG-BMI)is a novel indicator of insulin resistance(IR).Obstructive sleep apnea(OSA)is a prevalent disorder characterized by recurrent complete or partial collapse of the pharyngeal airway during sleep;however,the relationship between these two conditions remains unexplored.We hypothesized that a higher TyG-BMI is associated with the occurrence of OSA.AIM To assess the association between TyG-BMI and OSA in adults in the United States.METHODS A cross-sectional study was conducted utilizing data from the National Health and Nutrition Examination Surveys spanning from 2005-2008 to 2015-2018.TyGBMI was calculated as Ln[triglyceride(mg/dL)×fasting blood glucose(mg/dL)/2]×BMI.Restricted cubic splines were used to analyze the risk of TyG-BMI and OSA occurrence.To identify potential nonlinear relationships,we combined Cox proportional hazard regression with smooth curve fitting.We also conducted sensitivity and subgroup analyses to verify the robustness of our findings.RESULTS We included 16794 participants in the final analysis.Multivariate regression analysis showed that participants with a higher TyG-BMI had a higher OSA incidence.After adjusting for all covariates,TyG-BMI was positively correlated with the prevalence of OSA(odds ratio:1.28;95%confidence interval:1.17,1.40;P<0.001);no significant nonlinear relationship was observed.Subgroup analysis showed no strong correlation between TyG-BMI and OSA in patients with diabetes.The correlation between TyG-BMI and OSA was influenced by age,sex,smoking status,marital status,hypertensive stratification,and obesity;these subgroups played a moderating role between TyGBMI and OSA.Even after adjusting for all covariates,there was a positive association between TYG-BMI and OSA prevalence.CONCLUSION A higher TyG-BMI index is linked to higher chances of developing OSA.As TyG-BMI is an indicator of IR,managing IR may help reduce the risk of OSA. 展开更多
关键词 Obstructive sleep apnea Triglyceride glucose-body mass index Insulin resistance cross-sectionAL National Health and Nutrition Examination Surveys
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A cross-sectional study of the association between dietary inflammatory index and glaucoma prevalence in a US population
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作者 Wen-Li Chen Li-Xia Zhang 《International Journal of Ophthalmology(English edition)》 2025年第1期139-145,共7页
AIM:To assess the relationship between dietary inflammatory index(DII)and prevalence of glaucoma among individuals aged 40y and above in the United States.METHODS:Participants were drawn from 2 cycles of the National ... AIM:To assess the relationship between dietary inflammatory index(DII)and prevalence of glaucoma among individuals aged 40y and above in the United States.METHODS:Participants were drawn from 2 cycles of the National Health and Nutrition Examination Survey(NHANES,2005-2008)for a cross-sectional study.DII was calculated from 24-hour dietary recall questionnaire conducted by experienced researchers and data analyzed in R according to the NHANES user guide,“Stratified Multi-stage Probability Sampling”.The relationship between DII and glaucoma was evaluated by multi-factor logistic regression analysis and the existence of a non-linear association examined by restricted cubic spline(RCS)analysis.RESULTS:A total of 5359 subjects were included and the cross-sectional analysis weighted to represent the US population of 109 million.DII was elevated in glaucoma patients(P<0.001)and smoking and alcohol use contributed to significant differences(P<0.001).DII correlated negatively with Healthy Eating Index(HEI)-2015(Spearman rank correlation coefficient,r=-0.49).RCS analysis showed a linear relationship between DII and glaucoma risk(P of non-linear relationship=0.575).CONCLUSION:An increased DII is strongly associated with high risk of glaucoma and diet-induced inflammation should be controlled to delay glaucoma progression. 展开更多
关键词 glaucoma risk factors dietar y inflammatory index National Health and Nutrition Examination Survey restricted cubic spline regression cross-sectional study
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Continuum of glucose and bone metabolism impairment across autonomous cortisol secretion: A cross-sectional study
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作者 Min-Min Han Xiao-Ming Cao +2 位作者 Zi-Ang Liu Yi Zhang Yun-Feng Liu 《World Journal of Diabetes》 2025年第3期134-145,共12页
BACKGROUND Autonomous cortisol secretion(ACS)is linked to a higher prevalence of metabolic abnormalities and an increased risk of major adverse cardiovascular events.AIM To evaluate glucose and bone metabolism in pati... BACKGROUND Autonomous cortisol secretion(ACS)is linked to a higher prevalence of metabolic abnormalities and an increased risk of major adverse cardiovascular events.AIM To evaluate glucose and bone metabolism in patients with ACS using a continuous glucose monitoring system(CGMS)and dual-energy X-ray absorptiometry(DXA).METHODS Patients diagnosed with ACS,including Cushing syndrome,mild ACS(MACS),and nonfunctional adrenal incidentaloma(NFAI),were recruited for this study.Glucose variability and glycemic status were assessed using CGMS.Regional bone mineral content(BMC),bone mineral density(BMD),and bone area(BA)were evaluated using DXA.CGMS-and DXA-derived parameters were compared across the subgroups of ACS.Correlation analysis was performed to examine relationships between varying degrees of cortisol secretion,measured by cortisol after 1 mg overnight dexamethasone suppression test(DST)or 24-hour urine free cortisol(24h UFC),and CGMS-or DXA-derived parameters.RESULTS A total of 64 patients with ACS were included in this study:19 with Cushing syndrome,11 with MACS,and 34 with NFAI.Glucose variability,time above range(TAR),and time in range(TIR)along with specific areal BMC,BMD,and BA,differed significantly between groups of Cushing syndrome and NFAI.A significant positive correlation was observed between glucose variability or TAR and cortisol after 1 mg overnight DST or 24h UFC.By contrast,TIR,along with regional BMC,BMD,and BA,were negatively correlated with varying degrees of cortisol secretion.CONCLUSION Glucose and bone metabolism impairments are on a continuum alteration from NFAI to MACS and Cushing syndrome.Prompt attention should be given to these patients with ACS,especially those with mild hormone secretion.Parameters of glucose variability and glycemic status along with bone condition in regions rich in cancellous bone will provide valuable information. 展开更多
关键词 Continuous glucose monitoring system Glucose variability Time in range Autonomous cortisol secretion Bone mineral content Bone mineral density Bone area
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Relationship between sonographically measured median nerve cross-sectional area and presence of peripheral neuropathy in diabetic subjects 被引量:8
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作者 Fredrick ANDrew Attah Christianah Mopelola Asaleye +3 位作者 Adeleye Dorcas Omisore Babatope Ayodeji Kolawole Adeniyi Sunday Aderibigbe Mathew Alo 《World Journal of Diabetes》 SCIE CAS 2019年第1期47-56,共10页
BACKGROUND Neuropathy is a common complication of diabetes mellitus resulting from direct damage by hyperglycemia to the nerves and/or ischemia by microvascular injury to the endoneurial vessels which supply the nerve... BACKGROUND Neuropathy is a common complication of diabetes mellitus resulting from direct damage by hyperglycemia to the nerves and/or ischemia by microvascular injury to the endoneurial vessels which supply the nerves. Median nerve is one of the peripheral nerves commonly affected in diabetic neuropathy. The median nerve size has been studied in non-Nigerian diabetic populations. In attempt to contribute to existing literature, a study in a Nigerian population is needed.AIM To evaluate the cross-sectional area(CSA) of the median nerve using B-mode ultrasonography(USS) and the presence of peripheral neuropathy(PN) in a cohort of adult diabetic Nigerians.METHODS Demographic and anthropometric data of 85 adult diabetes mellitus(DM) and 85 age-and sex-matched apparently healthy control(HC) subjects were taken. A complete physical examination was performed on all study subjects to determine the presence of PN and modified Michigan Neuropathy Screening Instrument(MNSI) was used to grade its severity. Venous blood was taken from the study subjects for fasting lipid profile(FLP), fasting blood glucose(FBG) and glycated haemoglobin(HbA1 c) while their MN CSA was evaluated at a point 5 cm proximal to(5 cmCATL) and at the carpal tunnel(CATL) by high-resolution Bmode USS. Data was analysed using SPSS version 22.RESULTS The mean MN CSA was significantly thicker in DM subjects compared to the HC at 5 cmCATL(P < 0.01) and at the CATL(P < 0.01) on both sides. The presence of diabetic peripheral neuropathy(DPN) further increased the MN CSA at the CATL(P < 0.05) but not at 5 cmCATL(P > 0.05). However, the severity of DPN had no additional effect on MN CSA 5 cm proximal to and at the CATL. There was no significant association between MN CSA and duration of DM and glycemic control.CONCLUSION Thickening of the MN CSA at 5 cmCATL and CATL is seen in DM. Presence of DPN is associated with worse thickening of the MN CSA at the CATL but not at5 cmCATL. Severity of DPN, duration of DM, and glycemic control had no additional effect on the MN CSA. 展开更多
关键词 MEDIAN nerve cross-sectionAL area SONOGRAPHY DIABETICS Peripheral NEUROPATHY
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Optimization Design of the Multi-Layer Cross-Sectional Layout of An Umbilical Based on the GA-GLM 被引量:1
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作者 YANG Zhi-xun YIN Xu +5 位作者 FAN Zhi-rui YAN Jun LU Yu-cheng SU Qi MAO Yandong WANG Hua-lin 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期247-254,共8页
Marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with multi-layers.The layout of these components direct... Marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with multi-layers.The layout of these components directly affects manufacturing,operation and storage performances of the umbilical.For the multi-layer cross-sectional layout design of the umbilical,a quantifiable multi-objective optimization model is established according to the operation and storage requirements.Considering the manufacturing factors,the multi-layering strategy based on contact point identification is introduced for a great number of functional components.Then,the GA-GLM global optimization algorithm is proposed combining the genetic algorithm and the generalized multiplier method,and the selection operator of the genetic algorithm is improved based on the steepest descent method.Genetic algorithm is used to find the optimal solution in the global space,which can converge from any initial layout to the feasible layout solution.The feasible layout solution is taken as the initial value of the generalized multiplier method for fast and accurate solution.Finally,taking umbilicals with a great number of components as examples,the results show that the cross-sectional performance of the umbilical obtained by optimization algorithm is better and the solution efficiency is higher.Meanwhile,the multi-layering strategy is effective and feasible.The design method proposed in this paper can quickly obtain the optimal multi-layer cross-sectional layout,which replaces the manual design,and provides useful reference and guidance for the umbilical industry. 展开更多
关键词 UMBILICAL cross-sectional layout MULTI-LAYERS GA-GLM optimization
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Ultrasonographic measurement of median nerve cross-sectional area reference values in a healthy Han population from Guiyang,China 被引量:3
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作者 Jun Chen Shan Wu Jun Ren 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第24期1883-1887,共5页
High-resolution ultrasonography was used to analyze the nerve cross-sectional area (CSA) of the median nerve at 7 sites: the wrist crease, pisiform bone, hamate bone, 6 cm proximal to the tip of the wrist crease, p... High-resolution ultrasonography was used to analyze the nerve cross-sectional area (CSA) of the median nerve at 7 sites: the wrist crease, pisiform bone, hamate bone, 6 cm proximal to the tip of the wrist crease, proximal forearm (where the nerve enters the pronator teres muscle), 4 cm proximal to the tip of the medial epicondyle, and mid-humerus (mid-point between elbow crease and axilla) in 200 healthy volunteers from Guiyang, China. Results showed similar CSA values between the left and right sides, but the CSA 6 cm proximal to the tip of the wrist crease, proximal forearm, 4 cm proximal to tip of the medial epicondyle, and mid-humerus in males was greater than that of females. Moreover, CSA values at the wrist crease, pisiform bone, and hamate bone were greater in the middle-aged and old groups when compared to the young group, and correlated with body mass and height. Thus, reference values of median nerve CSA of the upper limbs can facilitate the analysis of abnormal nerve conditions. 展开更多
关键词 ULTRASONOGRAPHY median nerve cross-sectional area Guiyang Han nationality
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Does the ratio of the carpal tunnel inlet and outlet cross-sectional areas in the median nerve reflect carpal tunnel syndrome severity? 被引量:6
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作者 Li Zhang Aierken Rehemutula +3 位作者 Feng Peng Cong Yu Tian-bin Wang Lin Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1172-1176,共5页
Although ultrasound measurements have been used in previous studies on carpal tunnel syndrome to visualize injury to the median nerve, whether such ultrasound data can indicate the severity of carpal tunnel syndrome r... Although ultrasound measurements have been used in previous studies on carpal tunnel syndrome to visualize injury to the median nerve, whether such ultrasound data can indicate the severity of carpal tunnel syndrome remains controversial. The cross-sectional areas of the median nerve at the tunnel inlet and outlet can show swelling and compression of the nerve at the carpal. We hypothesized that the ratio of the cross-sectional areas of the median nerve at the carpal tunnel inlet to outlet accurately reflects the severity of carpal tunnel syndrome. To test this, high-resolution ultrasound with a linear array transducer at 5–17 MHz was used to assess 77 patients with carpal tunnel syndrome. The results showed that the cut-off point for the inlet-to-outlet ratio was 1.14. Significant differences in the inlet-to-outlet ratio were found among patients with mild, moderate, and severe carpal tunnel syndrome. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.29 between mild and more severe(moderate and severe) carpal tunnel syndrome patients with 64.7% sensitivity and 72.7% specificity. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.52 between the moderate and severe carpal tunnel syndrome patients with 80.0% sensitivity and 64.7% specificity. These results suggest that the inlet-to-outlet ratio reflected the severity of carpal tunnel syndrome. 展开更多
关键词 nerve regeneration peripheral nerve injury ultrasonography carpal tunnel syndrome diagnosis cross-sectional area classification clinical laboratory technique electrodiagnosis median nerve 973 Program neural regeneration
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Association between triglyceride-glucose index and colorectal polyps:A retrospective cross-sectional study 被引量:1
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作者 Ya-Jie Teng Ying-Xue Yang +5 位作者 Jing-Jing Yang Qiu-Yan Lu Jia-Yi Shi Jian-Hao Xu Jie Bao Qing-Hua Wang 《World Journal of Gastrointestinal Endoscopy》 2024年第2期55-63,共9页
BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses met... BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses metabolic health and insulin resistance,and has been linked to gastrointestinal cancers.AIM To investigate the potential association between the TyG index and CPs,as the relation between them has not been documented.METHODS A total of 2537 persons undergoing a routine health physical examination and colonoscopy at The First People's Hospital of Kunshan,Jiangsu Province,China,between January 2020 and December 2022 were included in this retrospective cross-sectional study.After excluding individuals who did not meet the eligibility criteria,descriptive statistics were used to compare characteristics between patients with and without CPs.Logistic regression analyses were conducted to determine the associations between the TyG index and the prevalence of CPs.The TyG index was calculated using the following formula:Ln[triglyceride(mg/dL)×glucose(mg/dL)/2].The presence and types of CPs was determined based on data from colonoscopy reports and pathology reports.RESULTS A nonlinear relation between the TyG index and the prevalence of CPs was identified,and exhibited a curvilinear pattern with a cut-off point of 2.31.A significant association was observed before the turning point,with an odds ratio(95% confidence interval)of 1.70(1.40,2.06),P<0.0001.However,the association between the TyG index and CPs was not significant after the cut-off point,with an odds ratio(95% confidence interval)of 0.57(0.27,1.23),P=0.1521.CONCLUSION Our study revealed a curvilinear association between the TyG index and CPs in Chinese individuals,suggesting its potential utility in developing colonoscopy screening strategies for preventing CRC. 展开更多
关键词 Triglyceride-glucose index Colorectal polyps Colorectal cancer Insulin resistance cross-sectional study
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Mental health and insomnia problems in healthcare workers after the COVID-19 pandemic:A multicenter cross-sectional study 被引量:1
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作者 Wei Ding Min-Zhong Wang +8 位作者 Xian-Wei Zeng Zhen-Hua Liu Yao Meng Hui-Ting Hu Yuan Zhang Yu-Guang Guan Fan-Gang Meng Jian-Guo Zhang Shu Wang 《World Journal of Psychiatry》 SCIE 2024年第5期704-714,共11页
BACKGROUND Healthcare workers(HCWs)are at increased risk of contracting coronavirus disease 2019(COVID-19)as well as worsening mental health problems and insomnia.These problems can persist for a long period,even afte... BACKGROUND Healthcare workers(HCWs)are at increased risk of contracting coronavirus disease 2019(COVID-19)as well as worsening mental health problems and insomnia.These problems can persist for a long period,even after the pandemic.However,less is known about this topic.AIM To analyze mental health,insomnia problems,and their influencing factors in HCWs after the COVID-19 pandemic.METHODS This multicenter cross-sectional,hospital-based study was conducted from June 1,2023 to June 30,2023,which was a half-year after the end of the COVID-19 emergency.Region-stratified population-based cluster sampling was applied at the provincial level for Chinese HCWs.Symptoms such as anxiety,depression,and insomnia were evaluated by the Generalized Anxiety Disorder-7,Patient Health Questionnaire-9,and Insomnia Severity Index.Factors influencing the symptoms were identified by multivariable logistic regression.RESULTS A total of 2000 participants were invited,for a response rate of 70.6%.A total of 1412 HCWs[618(43.8%)doctors,583(41.3%)nurses and 211(14.9%)nonfrontline],254(18.0%),231(16.4%),and 289(20.5%)had symptoms of anxiety,depression,and insomnia,respectively;severe symptoms were found in 58(4.1%),49(3.5%),and 111(7.9%)of the participants.Nurses,female sex,and hospitalization for COVID-19 were risk factors for anxiety,depression,and insomnia symptoms;moreover,death from family or friends was a risk factor for insomnia symptoms.During the COVID-19 outbreak,most[1086(76.9%)]of the participating HCWs received psychological interventions,while nearly all[994(70.4%)]of them had received public psychological education.Only 102(7.2%)of the HCWs received individual counseling from COVID-19.CONCLUSION Although the mental health and sleep problems of HCWs were relieved after the COVID-19 pandemic,they still faced challenges and greater risks than did the general population.Identifying risk factors would help in providing targeted interventions.In addition,although a major proportion of HCWs have received public psychological education,individual interventions are still insufficient. 展开更多
关键词 COVID-19 Mental health Psychological symptoms INSOMNIA Sleep disorders cross-sectional study Epidemiological study
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Aerodynamic effects on a railway tunnel with partially changed cross-sectional area 被引量:5
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作者 LI Wen-hui LIU Tang-hong +3 位作者 MARTINEZ-VAZQUEZ Pedro XIA Yu-tao CHEN Zheng-wei GUO Zi-jian 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第8期2589-2604,共16页
The present study numerically explored the aerodynamic performance of a novel railway tunnel with a partially reduced cross-section.The impact of the reduction rate of the tunnel cross-section on wave transmissions wa... The present study numerically explored the aerodynamic performance of a novel railway tunnel with a partially reduced cross-section.The impact of the reduction rate of the tunnel cross-section on wave transmissions was analyzed based on the three-dimensional,unsteady,compressible,and RNG k-εturbulence model.The results highlight that the reduction rate(S)most affects pressure configurations at the middle tunnel segment,followed by the enlarged segments near access,and finally the exit.The strength of the newly generated compression wave at the tunnel junction where the cross-section abruptly changes increases exponentially with the decrease of the cross-sectional area.The maximum peak-to-peak pressureΔP on the tunnel and train surface for non-uniform tunnels is reduced by 10.7%and 13.8%,respectively,compared with those of equivalent uniform tunnels.Overall,the economic analysis suggests that the aerodynamic performance of the developed tunnel prototype surpasses those conventional tunnels based on the same excavated volume. 展开更多
关键词 high-speed train railway tunnel cross-section transient pressure blockage ratio
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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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Wideband radar cross-section reduction by a double-layer-plasma-based metasurface
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作者 赵智明 李小平 +2 位作者 董果香 刘旭 牟相超 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期159-168,共10页
Reduction of the radar cross-section(RCS) is the key to stealth technology. To improve the RCS reduction effect of the designed checkerboard metasurface and overcome the limitation of thinlayer plasma in RCS reduction... Reduction of the radar cross-section(RCS) is the key to stealth technology. To improve the RCS reduction effect of the designed checkerboard metasurface and overcome the limitation of thinlayer plasma in RCS reduction technology, a double-layer-plasma-based metasurface—composed of a checkerboard metasurface, a double-layer plasma and an air gap between them—was investigated. Based on the principle of backscattering cancellation, we designed a checkerboard metasurface composed of different artificial magnetic conductor units;the checkerboard metasurface can reflect vertically incident electromagnetic(EM) waves in four different inclined directions to reduce the RCS. Full-wave simulations confirm that the doublelayer-plasma-based metasurface can improve the RCS reduction effect of the metasurface and the plasma. This is because in a band lower than the working band of the metasurface, the RCS reduction effect is mainly improved by the plasma layer. In the working band of the metasurface,impedance mismatching between the air gap and first plasma layer and between first and second plasma layers cause the scattered waves to become more dispersed, so the propagation path of the EM waves in the plasma becomes longer, increasing the absorption of the EM waves by the plasma. Thus, the RCS reduction effect is enhanced. The double-layer-plasma-based metasurface can be insensitive to the polarization of the incoming EM waves, and can also maintain a satisfactory RCS reduction band when the incident waves are oblique. 展开更多
关键词 stealth technology radar cross-section(RCS)reduction backscattering cancellation double-layer-plasma-based metasurface
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Dyslipidemia in Adults with Type 2 Diabetes in a Rural Community in Ganadougou, Mali: A Cross-Sectional Study
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作者 Abdoulaye Diawara Djibril Mamadou Coulibaly +22 位作者 Drissa Kone Mama A. Traore Drissa Konaté Dicko S. Bazi Oumar Kassogue Djeneba Sylla Fatoumata Gniné Fofana Oudou Diabaté Mariam Traore Ibrahim Antoine Nieantao Kaly Keїta Mamadou Diarra Olivia Smith Jian Li Cheickna Cisse Talib Yusuf Abbas Crystal Zheng Segun Fatumo Kassim Traore Mamadou Wele Mahamadou Diakité Seydou O. Doumbia Jeffrey G. Shaffer 《Journal of Diabetes Mellitus》 CAS 2024年第2期133-152,共20页
Dyslipidemia is a disorder where abnormally lipid concentrations circulate in the bloodstream. The disorder is common in type 2 diabetics (T2D) and is linked with T2D comorbidities, particularly cardiovascular disease... Dyslipidemia is a disorder where abnormally lipid concentrations circulate in the bloodstream. The disorder is common in type 2 diabetics (T2D) and is linked with T2D comorbidities, particularly cardiovascular disease. Dyslipidemia in T2D is typically characterized by elevated plasma triglyceride and low high-density lipoprotein cholesterol (HDL-C) levels. There is a significant gap in the literature regarding dyslipidemia in rural parts of Africa, where lipid profiles may not be captured through routine surveillance. This study aimed to characterize the prevalence and demo-graphic profile of dyslipidemia in T2D in the rural community of Ganadougou, Mali. We performed a cross-sectional study of 104 subjects with T2D in Ganadougou between November 2021 and March 2022. Demographic and lipid profiles were collected through cross-sectional surveys and serological analyses. The overall prevalence of dyslipidemia in T2D patients was 87.5% (91/104), which did not differ by sex (P = .368). High low-density lipoprotein cholesterol (LDL-C) was the most common lipid abnormality (78.9%, [82/104]). Dyslipidemia was associated with age and hypertension status (P = .013 and.036, respectively). High total and high LDL-C parameters were significantly associated with hypertension (P = .029 and .006, respectively). In low-resource settings such as rural Mali, there is a critical need to improve infrastructure for routine dyslipidemia screening to guide its prevention and intervention approaches. The high rates of dyslipidemia observed in Gandadougou, consistent with concomitant increases in cardiovascular diseases in Africa suggest that lipid profile assessments should be incorporated into routine medical care for T2D patients in African rural settings. 展开更多
关键词 CHOLESTEROL cross-sectional Study DYSLIPIDEMIA LIPIDS MALI Type 2 Diabetes
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Cross-section distortion and springback characteristics of double-cavity aluminum profile in force controlled stretch-bending
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作者 Zhi-wen LIU Zi-xuan DONG +2 位作者 Cong-chang XU Jie YI Luo-xing LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2476-2490,共15页
3D elastic-plastic FE model for simulating the force controlled stretch-bending process of double-cavity aluminum profile was established using hybrid explicit−implicit solvent method.Considering the computational acc... 3D elastic-plastic FE model for simulating the force controlled stretch-bending process of double-cavity aluminum profile was established using hybrid explicit−implicit solvent method.Considering the computational accuracy and efficiency,the optimal choices of numerical parameters and algorithms in FE modelling were determined.The formation mechanisms of cross-section distortion and springback were revealed.The effects of pre-stretching,post-stretching,friction,and the addition of internal fillers on forming quality were investigated.The results show that the stress state of profile in stretch-bending is uniaxial with only a circumferential stress.The stress distribution along the length direction of profile is non-uniform and the maximum tensile stress is located at a certain distance away from the center of profile.As aluminum profile is gradually attached to bending die,the distribution characteristic of cross-section distortion along the length direction of profile changes from V-shape to W-shape.After unloading the forming tools,cross-section distortion decreases obviously due to the stress relaxation,with a maximum distortion difference of 13%before and after unloading.As pre-stretching and post-stretching forces increase,cross-section distortion increases gradually,while springback first decreases and then remains unchanged.With increasing friction between bending die and profile,cross-section distortion slightly decreases,while springback increases.Cross-section distortion decreases by 83%with adding PVC fillers into the cavities of profile,while springback increases by 192.2%. 展开更多
关键词 hollow aluminum profile force controlled stretch-bending numerical parameters springback analysis approach cross-section distortion SPRINGBACK process parameters
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Prediction of(n,2n)reaction cross-sections of long-lived fission products based on tensor model
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作者 Jia-Li Huang Hui Wang +7 位作者 Ying-Ge Huang Er-Xi Xiao Yu-Jie Feng Xin Lei Fu-Chang Gu Long Zhu Yong-Jing Chen Jun Su 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期208-221,共14页
Interest has recently emerged in potential applications of(n,2n)reactions of unstable nuclei.Challenges have arisen because of the scarcity of experimental cross-sectional data.This study aims to predict the(n,2n)reac... Interest has recently emerged in potential applications of(n,2n)reactions of unstable nuclei.Challenges have arisen because of the scarcity of experimental cross-sectional data.This study aims to predict the(n,2n)reaction cross-section of long-lived fission products based on a tensor model.This tensor model is an extension of the collaborative filtering algorithm used for nuclear data.It is based on tensor decomposition and completion to predict(n,2n)reaction cross-sections;the corresponding EXFOR data are applied as training data.The reliability of the proposed tensor model was validated by comparing the calculations with data from EXFOR and different databases.Predictions were made for long-lived fission products such as^(60)Co,^(79)Se,^(93)Zr,^(107)P,^(126)Sn,and^(137)Cs,which provide a predicted energy range to effectively transmute long-lived fission products into shorter-lived or less radioactive isotopes.This method could be a powerful tool for completing(n,2n)reaction cross-sectional data and shows the possibility of selective transmutation of nuclear waste. 展开更多
关键词 (n 2n)Reaction cross-section Tensor model Machine learning Collaborative filtering algorithm Selective transmutation
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Correlation between current and cross-sectional area of parallel fixed-movable dual electrodes in ESC
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作者 Li-ting Zhao Yun-long Xiong +2 位作者 Rui Chen Zeng-rui Wang An-guo Wang 《China Foundry》 SCIE 2020年第3期245-249,共5页
Electroslag casting with parallel fixed-movable dual electrodes is a new method for achieving better quality of castings in complex mold cavities.In this work,a mathematical model,y=kx^2+(k+1)x,was established to desc... Electroslag casting with parallel fixed-movable dual electrodes is a new method for achieving better quality of castings in complex mold cavities.In this work,a mathematical model,y=kx^2+(k+1)x,was established to describe the ideal correlation between the current ratio(y)and the cross-sectional area ratio(x)of the dual electrodes,where k is the filling ratio.Investigation was conducted on the electroslag casting process with dual electrodes of various cross-sectional areas,but at a constant k value.The experimental results indicated that the ideal correlation was obtained at the stable casting stage,and the fitting results were consistent with the experimental results at certain k values.The experimental findings show that better castings can be obtained when the current ratio is greater than 1.536 and the cross-sectional area ratio is greater than 0.5. 展开更多
关键词 electroslag casting fixed-movable dual electrode current ratio cross-sectional area ratio
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Usefulness of the acromioclavicular joint cross-sectional area as a diagnostic image parameter of acromioclavicular osteoarthritis
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作者 Young Joo Jee Youn Moon +5 位作者 Jung Youn Han Yun-Sic Bang Keum Nae Kang Young Su Lim Young-SoonChoi Young-Uk Kim 《World Journal of Clinical Cases》 SCIE 2022年第7期2087-2094,共8页
BACKGROUND Acromioclavicular joint(ACJ)space narrowing has been considered to be an important diagnostic image parameter of ACJ osteoarthritis(ACJO).However,the morphology of the ACJ space is irregular because of oste... BACKGROUND Acromioclavicular joint(ACJ)space narrowing has been considered to be an important diagnostic image parameter of ACJ osteoarthritis(ACJO).However,the morphology of the ACJ space is irregular because of osteophyte formation,subchondral irregularity,capsular distention,sclerosis,and erosion.Therefore,we created the ACJ cross-sectional area(ACJCSA)as a new diagnostic image parameter to assess the irregular morphologic changes of the ACJ.AIM To hypothesize that the ACJCSA is a new diagnostic image parameter for ACJO.METHODS ACJ samples were obtained from 35 patients with ACJO and 30 healthy individuals who underwent shoulder magnetic resonance(S-MR)imaging that revealed no evidence of ACJO.Oblique coronal,T2-weighted,fat-suppressed SMR images were acquired at the ACJ level from the two groups.We measured the ACJCSA and the ACJ space width(ACJSW)at the ACJ on the S-MR images using our imaging analysis program.The ACJCSA was measured as the cross-sectional area of the ACJ.The ACJSW was measured as the narrowest point between the acromion and the clavicle.RESULTS The average ACJCSA was 39.88±10.60 mm;in the normal group and 18.80±5.13 mm;in the ACJO group.The mean ACJSW was 3.51±0.58 mm in the normal group and 2.02±0.48 mm in the ACJO group.ACJO individuals had significantly lower ACJCSA and ACJSW than the healthy individuals.Receiver operating characteristic curve analyses demonstrated that the most suitable ACJCSA cutoff score was 26.14 mm^(2),with 91.4%sensitivity and 90.0%specificity.CONCLUSION The optimal ACJSW cutoff score was 2.37 mm,with 88.6%sensitivity and 96.7%specificity.Even though both the ACJCSA and ACJSW were significantly associated with ACJO,the ACJCSA was a more sensitive diagnostic image parameter. 展开更多
关键词 Acromioclavicular joint OSTEOARTHRITIS cross-sectional area DIAGNOSIS
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Patterns of Infertility and Abortion in Saudi Arabia: A Cross-Sectional Study
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作者 Majed Saeed Alshahrani 《Open Journal of Obstetrics and Gynecology》 2024年第6期911-922,共12页
Background: Infertility and abortion are significant reproductive health concerns globally, impacting individuals' well-being and healthcare systems. In Saudi Arabia, cultural, social, and religious factors influe... Background: Infertility and abortion are significant reproductive health concerns globally, impacting individuals' well-being and healthcare systems. In Saudi Arabia, cultural, social, and religious factors influence perceptions and management of these issues, necessitating research to understand the patterns and associated factors. Study Aim: This cross-sectional study aimed to investigate the patterns of infertility and abortion among 458 women in Saudi Arabia, focusing on demographic profiles, reproductive histories, medical conditions, and lifestyle factors. Methodology: Participants were recruited from healthcare facilities, and data on age, BMI, reproductive history, medical conditions, assisted reproduction methods, and lifestyle behaviors were collected. Statistical analyses, including chi-square tests, were conducted to examine associations between variables. Results: The majority of participants were aged 30 - 39 years (47.4%), with 76.9% experiencing secondary infertility. Among those with offspring (76.9%), 31% reported using assisted reproduction methods, primarily ovarian stimulators (54.2%). Abortion history was reported by 39.5% of participants. Significant associations were found between age and infertility type (X2 = 5.8, p = 0.054), having offspring and infertility type (X2 = 458.0, p = 0.001), menstrual irregularity and infertility type (X2 = 11.4, p = 0.001), and abortion history and delayed fertility (X2 = 10.4, p = 0.001). Conclusion: Our study reveals significant associations between demographic, medical, and lifestyle factors with infertility patterns and abortion history among Saudi women. These findings emphasize the need for tailored interventions addressing medical conditions, age-related factors, and access to reproductive healthcare services. 展开更多
关键词 INFERTILITY ABORTION Saudi Arabia Reproductive Health Assisted Reproduction cross-sectional Study
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Theoretical analysis of the double-differential cross-sections of neutron,proton,deuteron,^(3)He,andαfor the p+^(6) Li reaction
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作者 Fang-Lei Zou Xiao-Jun Sun +10 位作者 Jing-Shang Zhang Hai-Rui Guo Yin-Lu Han Rui-Rui Xu Xi Tao Ji-Min Wang Xiao-Dong Sun Yuan Tian Tao Ye Yong-Li Xu Chun-Tian Liang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期181-197,共17页
Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of l... Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the targets.The reaction channels,including sequential and simultaneous emission processes,are analyzed in detail.Taking the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted particles.The optical potential parameters of the proton are obtained by fitting the elastic scattering differential cross-sections.The calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing angles.Simultaneously,the mixed double differential cross-sections of^(3) He andαare in good agreement with the measurements.The agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction processes.Based on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles. 展开更多
关键词 Statistical theory of light nucleus reaction p+^(6)Li reaction Light composite charged particle Double-differential cross-sections Two-body breakup Three-body breakup
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First Born Double Differential Cross-Section for Ionization of H (3d) by Incident Electron Impact
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作者 Sushmita Banerjee Sunil Dhar 《Open Journal of Microphysics》 2024年第2期67-77,共11页
Double differential cross section (DDCS) of First-Born approximation is calcu-lated for the ionization of metastable 3d-state hydrogen atoms by electron impact energy at 150 eV and 250 eV. A multiple scattering theory... Double differential cross section (DDCS) of First-Born approximation is calcu-lated for the ionization of metastable 3d-state hydrogen atoms by electron impact energy at 150 eV and 250 eV. A multiple scattering theory is applied in the present study. The present results are compared with the other related the-oretical results for the ionization of hydrogen atoms from different metastable states and ground-state experimental results. The findings demonstrate a strong qualitative agreement with the existing results. The obtained results have an extensive scope for further study of such an ionization process. 展开更多
关键词 Electron IONIZATION cross-section SCATTERING
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