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Characteristics of different aged plantations of Ormosia hosiei with regards to soil microbial biomass and enzymatic activities
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作者 Xiaolong Zhao Peilin Xie +5 位作者 Xueqian Zhang Zeyu Ou Haoxuan Ma Chun Suo Jingqi Ma Pan Wan 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期121-134,共14页
Stand age is an important indicator of tree growth and life cycle,and has implications for ecological and biological processes.This study examined changes in soil microbial biomass(SMB)as well as enzyme activities of ... Stand age is an important indicator of tree growth and life cycle,and has implications for ecological and biological processes.This study examined changes in soil microbial biomass(SMB)as well as enzyme activities of different aged plantations and revealed their relationship to soil properties.SMB,microbial biomass carbon(MBC),microbial biomass nitrogen(MBN),microbial biomass phos-phorous(MBP)and enzyme activities(β-1,4-glucosidase(β-G),β-1,4-xylosidase(β-X),cellobiohydrolase(CBH),leucine aminopeptidase(LAP),β-1,4-n-acetylglucosamine(NAG)and acid phosphatase(ACP))were measured in Oro-mosia hosiei plantations of different ages.The soil qual-ity index(SQI)model assessed soil quality.SMB contents significantly decreased in young(7-year-old)and mature plantations(45-year-old)compared to middle-aged(20-year-old)plantations.Activity of soilβ-G,β-X,CBH and NAG in the 20-year-old plantations was markedly higher than in the other plantations except forβ-G,CBH and NAG in the 45-year-old plantations.Soil organic carbon(SOC),total potassium(TK),total porosity,dissolved organic carbon,nitrate nitrogen(NO_(3)--N)and non-capillary porosity were key factors affecting SMB,while soil bulk density,pH,SOC,NO_(3)--N,TK and forest litter(FL)were the main factors affecting soil enzyme activities.SQI decreased in the order:middle-aged>mature>young.The efficiency of soil organic matter conversion,the effect of nitrogen min-eralization and fixation by microorganisms,and the better efficiency of phosphorus utilization in mid-age plantations,which improves soil physical properties,better facilitates tree growth,and further improves the buffering of the soil against acidity and alkalinity.FL quality was the only soil biological factor affecting soil enzyme activity.Our findings demonstrate that different aged plantations affect soil micro-bial biomass,enzyme activity,and soil quality. 展开更多
关键词 Plantation age Soil properties Microbial metabolism Soil health Environmental impact
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Evaluation of Compatibilizers for Improving Compatibility between Waste Vegetable Oil and Aged Asphalt
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作者 WANG Yanghui DING Yongjie +3 位作者 LI Danli CAO Zhilong SUN Guoqiang MEI Zijun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1278-1286,共9页
Modifying agents 2,2-Bis(4-glycidyloxyphenyl)propane(2BPE)and dibutyl phthalate(DBP)were selected to enhance the compatibility.By using molecular simulation software(Materials Studio,MS),nine systems were constructed,... Modifying agents 2,2-Bis(4-glycidyloxyphenyl)propane(2BPE)and dibutyl phthalate(DBP)were selected to enhance the compatibility.By using molecular simulation software(Materials Studio,MS),nine systems were constructed,including molecular models of aged asphalt and WVO monomers with 2BPE and/or DBP.The solubility parameters,Flory-Huggins parameters,and interaction energies of these systems were calculated to determine the impact of 2BPE and DBP on the compatibility of WVO and aged asphalt.Results showed that the addition of 2BPE and DBP reduced the difference in the solubility parameters between WVO and aged asphalt,thus improving the compatibility between WVO and aged asphalt.Additionally,using a combination of 2BPE and DBP in both aged asphalt and rejuvenator was found to be more effective than using either 2BPE or DBP alone.Finally,it was determined that evaluating the compatibility of WVO and aged asphalt using Van der Waals potential and non-bonding energy as evaluation indicators was more accurate than using electrostatic potential energy. 展开更多
关键词 road engineering aged asphalt compatibility molecular dynamics solubility parameter Flory-Huggins parameter
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Characteristics of the HIV/AIDS Epidemic among People Aged≥50 Years in China during 2018–2021
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作者 HOU Yu Shan JIN Yi Chen +3 位作者 CAI Chang TANG Hou Lin QIN Qian Qian LYU Fan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第4期399-405,共7页
Objective This study aimed to determine the current epidemiological status of PLWHA aged≥50 years in China from 2018 to 2021.It also aimed to recommend targeted interventions for the prevention and treatment of HIV/A... Objective This study aimed to determine the current epidemiological status of PLWHA aged≥50 years in China from 2018 to 2021.It also aimed to recommend targeted interventions for the prevention and treatment of HIV/AIDS in elderly patients.Methods Data on newly reported cases of PLWHA,aged≥50 years in China from 2018 to 2021,were collected using the CRIMS.Trend tests and spatial analyses were also conducted.Results Between 2018 and 2021,237,724 HIV/AIDS cases were reported among patients aged≥50 years in China.The main transmission route was heterosexual transmission(91.24%).Commercial heterosexual transmission(CHC)was the primary mode of transmission among males,while non-marital non-CHC([NMNCHC];60.59%)was the prevalent route in women.The proportion of patients with CHC decreased over time(Z=67.716,P<0.01),while that of patients with NMNCHC increased(Z=153.05,P<0.01).The sex ratio varied among the different modes of infection,and it peaked at 17.65 for CHC.The spatial analysis indicated spatial clustering,and the high-high clustering areas were mainly distributed in the southwestern and central-southern provinces.Conclusion In China,PLWHA,aged≥50 years,were predominantly infected through heterosexual transmission.The primary modes of infection were CHC and NMNCHC.There were variations in the sex ratio among different age groups,infected through various sexual behaviors.HIV/AIDS cases exhibited spatial clustering.Based on these results,the expansion of HIV testing,treatment,and integrated behavioral interventions in high-risk populations is recommended to enhance disease detection in key regions. 展开更多
关键词 HIV/AIDS aged≥50 years China
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Laboratory Evaluation of Performance Recovery of Aged SBS-modified Asphalt Using Regenerants with Different Base Oil Components
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作者 Li Hongzhen Li Shengbin +3 位作者 Feng Zhuangzhuang Jiang Mengmeng Li Ning Dong Fuqiang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期98-107,共10页
In this study,the regenerative effects of different regenerants on aged SBS-modified asphalt from different perspectives were investigated,including their conventional properties,viscoelastic behavior,creep-related pr... In this study,the regenerative effects of different regenerants on aged SBS-modified asphalt from different perspectives were investigated,including their conventional properties,viscoelastic behavior,creep-related properties,and micromorphology.Base oils composed of different proportions of aromatic and saturated hydrocarbons as well as the styrene-butadiene-styrene(SBS)restorer were used to prepare the regenerants.The results showed that the components of the base oil of the regenerant played a crucial role in determining the characteristics and performance of the recycled SBSmodified asphalt.Regenerants containing a high proportion of aromatics dissolved the hard segment in the SBS restorer,thereby delaying the effect of a reduction in the regenerants on the performance of the aged asphalts at a high temperature.Regenerants containing a high proportion of saturates dissolved the soft segment in the SBS restorer to enhance the lowtemperature performance of the recycled asphalts.In addition,the stress sensitivity of the recycled asphalts increased with the fraction of aromatics in the regenerant.As the aromatic content of the base oil components of the regenerants increased and their saturate content decreased,the state of dispersion of the SBS phase in the recycled SBS-modified asphalts improved.The optimal content of aromatics in the base oil of the regenerants should be set in the range of 33%to 47%to ensure the adequate performance of the recycled asphalts and a high efficiency of the SBS restorer. 展开更多
关键词 aged SBS-modified asphalt regeneration mechanisms base oil rheological properties MORPHOLOGY
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Microbiomics and metabolomics insights into the microbial regulation on the formation of flavor components in the traditional fermentation process of Chinese Hongqu aged vinegar
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作者 Shangong Tong Wenlong Li +7 位作者 Yuandong Rao Yanqin Xiao Yingyin Yan Weiling Guo Xucong Lü Jinyuan Sun Lianzhong Ai Li Ni 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2765-2778,共14页
This study aimed to investigate microbial succession and metabolic dynamics during the traditional fermentation of Hongqu aged vinegar,and explore the core functional microbes closely related to the formation of flavo... This study aimed to investigate microbial succession and metabolic dynamics during the traditional fermentation of Hongqu aged vinegar,and explore the core functional microbes closely related to the formation of flavor components.Microbiome analysis demonstrated that Lactobacillus,Acetobacter,Bacillus,Enterobacter,Lactococcus,Leuconostoc and Weissella were the predominant bacterial genera,while Aspergillus piperis,Aspergillus oryzae,Monascus purpureus,Candida athensensis,C.xylopsoci,Penicillium ochrosalmoneum and Simplicillium aogashimaense were the predominant fungal species.Correlation analysis revealed that Acetobacter was positively correlated with the production of tetramethylpyrazine,acetoin and acetic acid,Lactococcus showed positive correlation with the production of 2-nonanone,2-heptanone,ethyl caprylate,ethyl caprate,1-hexanol,1-octanol and 1-octen-3-ol,C.xylopsoci and C.rugosa were positively associated with the production of diethyl malonate,2,3-butanediyl diacetate,acetoin,benzaldehyde and tetramethylpyrazine.Correspondingly,non-volatile metabolites were also detected through ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry.A variety of amino acids and functional dipeptides were identified during the traditional brewing of Hongqu aged vinegar.Correlation analysis revealed that Lactobacillus was significantly associated with DL-lactate,indolelactic acid,D-(+)-3-phenyllactic acid,pimelic acid,pregabalin and 3-aminobutanoic acid.This study is useful for understanding flavor formation mechanism and developing effective strategies for the suitable strains selection to improve the flavor quality of Hongqu aged vinegar. 展开更多
关键词 Hongqu aged vinegar Traditional fermentation Microbial dynamics Flavor components Bidirectional orthogonal partial least squares
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Weldability of steel used in an aged bridge
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作者 Hirohata Mikihito 《China Welding》 CAS 2024年第3期33-38,共6页
A series of experiments was performed to investigate the weldability of steel used in an aged bridge.A steel material used in an aged railway bridge constructed in 1912 was extracted for this investigation.The chemica... A series of experiments was performed to investigate the weldability of steel used in an aged bridge.A steel material used in an aged railway bridge constructed in 1912 was extracted for this investigation.The chemical compositions of this steel were suitable for welding.However,the aged steel contained much sulfur.Cruciform welded joints were fabricated with this aged steel.Welding defects or cracks were not observed in the joints.The Vickers hardness test on the welded part did not confirm extreme hardening or softening.After yielding by the static tensile test,the cruciform joints were fractured at the welded parts.One of the specimens was fractured in the middle of the thickness of the aged steel.The Sulfur contained in the aged steel might cause this type of fracture.The results show that there may be a risk of brittle fracture not only from the welded part but also from the base metal.The chemical compositions of aged steel must be analyzed when repair welding is applied to the steel. 展开更多
关键词 aged steel bridge repair welding chemical compositions weld defect brittle fracture
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Risk Factors for Geo-Helminthiasis in Children Aged 6 - 36 Months in a Rural Health District in Cameroon
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作者 Isabelle Mekone Nkwele Monono Naiza +6 位作者 Gervais Talla Kamga Hugues Nana Djeunga Jeannette Epée Ngoue Patricia Epée Eboumbou Suzanne Ngo Um Sap Evelyn Mah Mungeh Joseph Kamgno 《Open Journal of Pediatrics》 2024年第2期391-400,共10页
Introduction and Objectives: Soil-Transmitted-Helminthiasis (STH) is a public health problem in Cameroon. The control strategies currently in place, particularly chemoprevention, has shortcomings linked to the target ... Introduction and Objectives: Soil-Transmitted-Helminthiasis (STH) is a public health problem in Cameroon. The control strategies currently in place, particularly chemoprevention, has shortcomings linked to the target population, which are school-age children. The objective was to determine the prevalence and the risk factors associated with geo-helminthiasis in children aged 0 to 3 years in a rural health district. Method: From December 2020 to May 2021, a descriptive and analytical cross-sectional study of 376 children between 6 and 36 months was carried out in the Akonolinga health district. This was a cluster sampling in 4 health areas. Stool samples were collected and analysed using the mini-FLOTAC method. The results expressed as the number of eggs per gram of stool. A questionnaire on socio-demographic and lifestyle data was administered to the parents. The Chi-squared test was used to measure the association between geo-helminth infection and the data collected. A multivariate analysis using logistic regression was performed (p 0.05). Results: The prevalence of STH was 19.4% (Ascaris lumbricoides: 16% and Trichuris trichiura: 8%). Risk factors were: consumption of contaminated water (AOR = 1.93 [1.03 - 3.6];p = 0.040), early contact of the child with the ground (before age of 4 months) (AOR = 4.9 [2.1 - 11.37];p .001), habit of walking barefoot (AOR = 2.91 [1.1 - 7.97];p = 0.038), and living in a habitat with unpaved ground (AOR = 7.4 [1.55 - 35.7];p = 0.012). Conclusion: The prevalence of STHs in infants was high. Preventive chemotherapy should be extended to this age-group, and other measures intensified. 展开更多
关键词 Akonolinga Soil-Transmitted-Helminths Children aged 0 - 3 Years Risk Factors
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Factors Associated with Acute Respiratory Infections in Children Aged 0 - 5 Years in the Yénawa District of Cotonou (Benin) in 2023
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作者 Virginie Mongbo Luc Béhanzin +2 位作者 Lamidhi Salami Nicolas Hamondji Amegan Edgard-Marius Ouendo 《Open Journal of Epidemiology》 2024年第2期331-342,共12页
Introduction: Acute respiratory infections remain one of the main causes of mortality in children aged 0 to 5. This work aimed to study the associated factors with the occurrence of acute respiratory infections in chi... Introduction: Acute respiratory infections remain one of the main causes of mortality in children aged 0 to 5. This work aimed to study the associated factors with the occurrence of acute respiratory infections in children 0 to 5 years old in Yénawa, Cotonou in 2023. Subjects and Method: It was an analytical cross-sectional study of children aged 0 - 5 years and their mothers in Yénawa, selected by four-degree random sampling. The sampling size, calculated using the Schwartz formula, was 126 children and 126 mothers. The dependent variable was the occurrence of acute respiratory infections. The independent variables were classified into four groups: socio-demographic and economic characteristics, behavioral factors, child-related factors, and environmental factors. Data collected by observation and questionnaire survey were analyzed using STATA version 15 software. Associated factors were investigated by bivariate analysis and multiple logistic regression, at the 5% significance level. Results: A total of 126 children aged 0 - 5 years and 126 mothers were surveyed, aged 23.5 (11 - 36) months and 30 (18 - 48) years respectively. The prevalence of acute respiratory infections was 74.60% (CI95% = 66.89 to 82.30). The associated factors were the mother’s age between 18 and 28 (OR = 10.77;CI95% = 1.89 to 61.27;p = 0.007), the use of charcoal/wood for cooking (OR = 7.36;IC = 1.99 to 27.10;p = 0.003)), children's poor personal hygiene (OR = 8.87;IC = 2.92 to 26.97;p 0.001)), and cohabitation with domestic animals (OR = 7.27;IC = 1.67 to 31.71;p = 0.015). Conclusion: Communicating with mothers about the factors identified will help reduce the prevalence of acute respiratory infections in children aged 0 to 5. 展开更多
关键词 Acute Respiratory Infections Children aged 0 - 5 Associated Factors Yénawa BENIN
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Factors Associated with Mortality in Children Aged 1 Month to 15 Years Hospitalized in the Pediatric Ward of the Kalaban-Coro Reference Health Center: Cross-Sectional Study
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作者 Abdoul Salam Diarra Mohamed Diarra +13 位作者 Dramane Touré Tawfiq Abu Beyadari Balilé Harber Maimouna Kanté Issa Guindo Belco Maiga Karamoko Sacko Kalirou Traoré Fatoumata Dicko Mamadou Togo Kalba Pélieba Mariam Sylla Mamadou Samaké Hamadoun Sangho 《Open Journal of Pediatrics》 2024年第5期800-813,共14页
Introduction: Infant and child mortality is a worldwide concern, but developing countries such as Mali are more affected. The aim of this study was to investigate morbidity and factors associated with mortality in chi... Introduction: Infant and child mortality is a worldwide concern, but developing countries such as Mali are more affected. The aim of this study was to investigate morbidity and factors associated with mortality in children aged 1 month to 15 years. Methodology: This was a cross-sectional study which took place from January 1 to December 31, 2020 covering children aged 1 month to 15 years hospitalized at the Kalaban-Coro CSRéf. Data were entered into Excel and analyzed using SPSS version 20 software. Results: Five hundred children aged 1 months to 15 years were included. The age range 1 to 5 years (53.6%) and male sex (58.2%) were the most represented. Malaria (72.2%), acute respiratory infections (6.2%) and diarrhea/dehydration (3%) were the main morbidities. Mortality was estimated at 10.6%, and the two main causes of death were malaria (56.6%) and acute respiratory infections (7.54%). Univariate analysis revealed a statistically significant association between the dependent variable (death) and age (p Conclusion: This study confirms the high rate of infant and child morbidity and mortality in our health facilities. Strengthening human resources and intensifying behavior-change communication can help reverse the trend. 展开更多
关键词 Children aged 1 Months to 15 Years MORBIDITY Factors Associated with Mortality MORBIDITY
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The Association Between Daily Physical Activity and Risk of Hypertension in Middle-Aged and Older Adults:A Nationwide Cohort Study in China
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作者 Junhua Zhang Jie Rong +1 位作者 Hui Zhang Yongmei Yan 《Journal of Clinical and Nursing Research》 2024年第9期83-92,共10页
Physical activity (PA) plays a key role in the treatment of hypertension, and moderate to vigorous PA has been documented to lower the risk of developing hypertension. However, dose-response relationships between PA a... Physical activity (PA) plays a key role in the treatment of hypertension, and moderate to vigorous PA has been documented to lower the risk of developing hypertension. However, dose-response relationships between PA and hypertension are not consistent, and little is known about this relationship within the Chinese middle-aged and older people. We investigated the relationship between PA and hypertension within this population using China Health and Nutrition Survey 1991-2015 data. Physical activity was expressed in terms of the metabolic equivalent task (MET) and participants were divided into groups according to quartiles, namely, Q1 (< 32.97 METs-h/w), Q2 (32.97-60.38 METs-h/ w), Q3 (60.38-98.95 METs-h/w), and Q4 (> 98.95 METs-h/w). Compared with the Q1 group, the odds ratio of risk with hypertension (95% CIs) after adjusting for confounding factors were 0.63 (0.35, 1.12), 0.49 (0.28, 0.86), and 0.62 (0.35, 1.09) for those in Q2, Q3, and Q4, respectively. Restricted cubic spline functions were used and a U-shaped relationship between physical activity and hypertension risk was found, indicative of an optimal level of physical activity, which was found to be 112 METs-h/w. Our data suggest maintenance of optimal levels of total daily physical activity may be important for preventing hypertension in Chinese adults over the age of 40. 展开更多
关键词 Physical activity HYPERTENSION Middle age Older adults
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Metformin promotes angiogenesis and functional recovery in aged mice after spinal cord injury by adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway 被引量:3
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作者 Jin-Yun Zhao Xiao-Long Sheng +7 位作者 Cheng-Jun Li Tian Qin Run-Dong He Guo-Yu Dai Yong Cao Hong-Bin Lu Chun-Yue Duan Jian-Zhong Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1553-1562,共10页
Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of a... Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury. 展开更多
关键词 adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway ANGIOGENESIS aged mice compound C METFORMIN spinal cord injury
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Impact of age on transcatheter aortic valve implantation outcomes:a comparison of patients aged≤ 80 years versus patients &gt; 80 years 被引量:2
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作者 Frank van der Kley Philippe J van Rosendael +8 位作者 Spyridon Katsanos Vasileios Kamperidis Nina A Marsan Ioannis Karalis Arend de Weger Meindert Palmen Jeroen J Bax Martin J Schalij Victoria Delgado 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第1期31-36,共6页
ObjectiveTo investigate the procedural outcomes and the long-term survival of patients undergoing transcatheter aortic valve implantation (TAVI) and compare study results of patients≤ 80 years and patients &gt; 80... ObjectiveTo investigate the procedural outcomes and the long-term survival of patients undergoing transcatheter aortic valve implantation (TAVI) and compare study results of patients≤ 80 years and patients &gt; 80 years old.MethodsA total of 240 patients treated with TAVI were divided into two groups according to age≤ 80 years (n = 105; 43.8%) and &gt; 80 years (n= 135; 56.2%). The baseline characteristics and the pro-cedural outcomes were compared between these two groups of patients.ResultsWith the exception of peripheral artery disease and hypercho-lesterolemia, which were more frequently observed in the older age group, baseline characteristics were comparable between groups. Complica-tion rates did not differ significantly between patients≤ 80 years and patients &gt; 80 years. There were no differences in 30-day mortality rates be-tween patients aged≤ 80 years and patients &gt; 80 years old (9.5%vs. 7.4%, respectively;P = 0.557). After a median follow-up of 28 months (in-terquartile range: 16-42 months), 50 (47.6%) patients aged≤ 80 years died compared to 57 (42%) deaths in the group of patients &gt; 80 years old (P= 0.404).ConclusionThe results of the present single center study showed that age did not significantly impact the outcomes of TAVI. 展开更多
关键词 age Survival rate Transcatheter aortic valve implantation
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Effects of process parameters on mechanical properties and microstructures of creep aged 2124 aluminum alloy 被引量:7
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作者 湛利华 李炎光 黄明辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2232-2238,共7页
A series of tests were carried microstructures of 2124 aluminum alloy in increase of aging time, temperature and low-to-peak-to-low manner. No significant out to investigate the effects of process parameters on mechan... A series of tests were carried microstructures of 2124 aluminum alloy in increase of aging time, temperature and low-to-peak-to-low manner. No significant out to investigate the effects of process parameters on mechanical properties and creep aging process. The results show that creep strain and creep rate increase with the applied stress. The hardness of specimen varies with aging time and stress in a effect of temperature on hardness of material is seen in the range of 185-195 ℃. The optimum mechanical properties are obtained at the conditions of (200 MPa, 185 ℃, 8 h) as the result of the coexistence of strengthening S" and S' phases in the matrix by transmission electron microscopy (TEM). TEM observation shows that applied stress promotes the formation and growth of precioitates and no obvious stress orientation effect is observed in the matrix. 展开更多
关键词 aluminum alloy creep aging behavior age hardening mechanical property MICROSTRUCTURE process parameter
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Study of Factors Associated with the Age of Natural Menopause in Menopausal Women Aged 30 to 80 Years from the Keur Massar Health District in 2015 (Senegal)
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作者 Fatoumata Binetou Diongue Adama Faye +4 位作者 Khadim Niang Jean Augustin Diégane Tine Amadou Ibra Diallo Rodrigue Magloire Eyema Anta Tal-Dia 《Health》 2020年第10期1333-1344,共12页
<strong>Introduction: </strong>Menopause is a biological phenomenon that occurs at a more or less early or late age in the life of every woman. The general objective is to study the factors associated with... <strong>Introduction: </strong>Menopause is a biological phenomenon that occurs at a more or less early or late age in the life of every woman. The general objective is to study the factors associated with the age of natural menopause in menopausal women aged between 30 and 80 years who have gone through down Keur Massar health district in 2015. <strong>Methodology:</strong> This was an observational, cross-sectional, descriptive and analytical study conducted in Keur Massar health district from December 1<sup>st</sup> to 10<sup>th</sup>, 2015. Two-stage cluster sampling was conducted. Data were collected during an individual interview at home after consent. They covered socio-economic conditions, health and nutrition status, gynecological-obstetrical history, and lifestyle. A multivariate analysis was performed using the Cox model with a 5% risk of alpha error. <strong>Results: </strong>A total of 627 postmenopausal women were surveyed. Mean age of these women was 54.5 years (±8.6 years). A proportion of 72.1% of the women was married and 46.7% was in school. Mean age of natural menopause was 47.1 years (±5.03 years). The median age of natural menopause was 47 years. Factors associated with the age of natural menopause were high parity of more than 4 children (Hra = 0.35 [0.13 - 0.92]), the existence of frequent childhood illnesses (Hra = 1.72 [1.13 - 2.64]), use of the intra-uterine device—IUD—as a modern contraceptive method (HRa = 0.39 [0.24 - 0.63]), sibling size (HRa = 0.85 [0.78 - 0.93]), family size (HRa = 1.03 [1.01 - 1.06]), and polygamy regime (HRa = 0.56 [0.37 - 0.85]). <strong>Conclusion: </strong>Many factors in childhood as well as during the period of female genital activity can impact the age of natural menopause. It is then important to improve the health status of women, children and the standard of living of the population. 展开更多
关键词 age Menopause Associated Factors SURVIVAL Senegal
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Age-specific differences in the association between prediabetes and cardiovascular diseases in China:A national cross-sectional study 被引量:1
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作者 Shuo Xie Li-Ping Yu +4 位作者 Fei Chen Yao Wang Rui-Fen Deng Xue-Lian Zhang Bo Zhang 《World Journal of Diabetes》 SCIE 2024年第2期240-250,共11页
BACKGROUND Cardiovascular disease(CVD)is a leading cause of morbidity and mortality worldwide,the global burden of which is rising.It is still unclear the extent to which prediabetes contributes to the risk of CVD in ... BACKGROUND Cardiovascular disease(CVD)is a leading cause of morbidity and mortality worldwide,the global burden of which is rising.It is still unclear the extent to which prediabetes contributes to the risk of CVD in various age brackets among adults.To develop a focused screening plan and treatment for Chinese adults with prediabetes,it is crucial to identify variations in the connection between prediabetes and the risk of CVD based on age.AIM To examine the clinical features of prediabetes and identify risk factors for CVD in different age groups in China.METHODS The cross-sectional study involved a total of 46239 participants from June 2007 through May 2008.A thorough evaluation was conducted.Individuals with prediabetes were categorized into two groups based on age.Chinese atherosclerotic CVD risk prediction model was employed to evaluate the risk of developing CVD over 10 years.Random forest was established in both age groups.SHapley Additive exPlanation method prioritized the importance of features from the perspective of assessment contribution.RESULTS In total,6948 people were diagnosed with prediabetes in this study.In prediabetes,prevalences of CVD were 5(0.29%)in the younger group and 148(2.85%)in the older group.Overall,11.11%of the younger group and 29.59% of the older group were intermediate/high-risk of CVD for prediabetes without CVD based on the Prediction for ASCVD Risk in China equation in ten years.In the younger age group,the 10-year risk of CVD was found to be more closely linked to family history of CVD rather than lifestyle,whereas in the older age group,resident status was more closely linked.CONCLUSION The susceptibility to CVD is age-specific in newly diagnosed prediabetes.It is necessary to develop targeted approaches for the prevention and management of CVD in adults across various age brackets. 展开更多
关键词 age Cardiovascular diseases PREDIABETES Risk factors DIFFERENCES
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Non-linear relationship between age and subfoveal choroidal thickness in Chinese patients with proliferative diabetic retinopathy 被引量:1
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作者 Chun-Yan Lei Jiang-Ying Xie +1 位作者 Qi-Bo Ran Mei-Xia Zhang 《World Journal of Diabetes》 SCIE 2024年第9期1903-1915,共13页
BACKGROUND No study has investigated the change regularity between age and subfoveal choroidal thickness(SFCT)in proliferative diabetic retinopathy(PDR).AIM To investigate the relationship between the SFCT and age in ... BACKGROUND No study has investigated the change regularity between age and subfoveal choroidal thickness(SFCT)in proliferative diabetic retinopathy(PDR).AIM To investigate the relationship between the SFCT and age in Chinese patients with PDR.METHODS This was a cross-sectional retrospective study.The participants were hospitalized individuals with type 2 diabetes who underwent vitrectomy for PDR.Contralateral eyes that met the criteria were included in the study.All necessary laboratory tests were performed at the time of admission.Central macular thickness(CMT)and SFCT were two quantitative assessments made using enhanced depth imaging optical coherence tomography.CMT was measured automatically and SFCT was measured manually with digital calipers provided by the Heidelberg Eye Explorer software.RESULTS The final analysis included a total of 234 individuals with PDR.The average age was 55.60 years old±10.03 years old,and 57.69%of the population was male.Univariate analysis revealed a significant negative connection between age and SFCT in patients with PDR[β=-2.44,95%confidence interval(95%CI):-3.46 to-1.42;P<0.0001].In the fully adjusted model,the correlation between SFCT and age remained steady(β=-1.68,95%CI:-2.97 to-0.39;P=0.0117).Spline smoothing showed that the relationship between SFCT and age in patients with PDR was non-linear,with an inflection point at 54 years of age.CONCLUSION Our findings suggest that age is a key determinant of choroidal thickness.The non-linear link between SFCT and age in PDR patients should be taken into account. 展开更多
关键词 age Subfoveal choroidal thickness Proliferative diabetic retinopathy Optical coherence tomography Central macular thickness
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Microstructure of Mg-8Zn-4Al-1Ca aged alloy 被引量:1
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作者 董允 林小娉 +2 位作者 叶杰 郑润国 何娜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期310-315,共6页
The microstructure of Mg-8Zn-4Al-1Ca aged alloy was investigated by TEM and HRTEM. The results show that the hardening produced in the Mg-8Zn-4Al-1Ca alloy is considerably higher than that in the Mg-8Zn-4A1 alloy. A d... The microstructure of Mg-8Zn-4Al-1Ca aged alloy was investigated by TEM and HRTEM. The results show that the hardening produced in the Mg-8Zn-4Al-1Ca alloy is considerably higher than that in the Mg-8Zn-4A1 alloy. A dense dispersion of disc-like Ca2Mg6Zn3 precipitates are formed in Mg-8Zn-4Al-1Ca alloy aged at 160 ℃ for 16 h. In addition, the lattice distortions, honeycomb-looking Moir&#233; fringes, edge dislocations and dislocation loop also exist in the microstructure. The precipitates of alloy aged at 160 ℃ for 48 h are coarse disc-like and fine dispersed grainy. When the alloy is subjected to aging at 160 ℃ for 227 h, the microstructure consists of numerous MgZn2 precipitates and Ca2Mg6Zn3 precipitates. All the analyses show that Ca is a particularly effective trace addition in improving the age-hardening and postponing the formation of MgZn2 precipitates in Mg-8Zn-4Al alloy aged at 160 ℃. 展开更多
关键词 Mg-8Zn-4Al-1 Ca alloy age hardening Ca2Mg6Zn3 Moire fringe
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Bowel preparation protocol for hospitalized patients ages 50 years or older:A randomized controlled trial 被引量:1
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作者 Yu He Qi Liu +3 位作者 Yi-Wen Chen Li-Jian Cui Kai Cao Zi-Hao Guo 《World Journal of Gastrointestinal Endoscopy》 2024年第1期18-28,共11页
BACKGROUND The incidence and mortality rate of colorectal cancer progressively increase with age and become particularly prominent after the age of 50 years.Therefore,the population that is≥50 years in age requires l... BACKGROUND The incidence and mortality rate of colorectal cancer progressively increase with age and become particularly prominent after the age of 50 years.Therefore,the population that is≥50 years in age requires long-term and regular colonoscopies.Uncomfortable bowel preparation is the main reason preventing patients from undergoing regular colonoscopies.The standard bowel preparation regimen of 4-L polyethylene glycol(PEG)is effective but poorly tolerated.AIM To investigate an effective and comfortable bowel preparation regimen for hospitalized patients≥50 years in age.METHODS Patients were randomly assigned to group 1(2-L PEG+30-mL lactulose+a lowresidue diet)or group 2(4-L PEG).Adequate bowel preparation was defined as a Boston bowel preparation scale(BBPS)score of≥6,with a score of≥2 for each segment.Non-inferiority was prespecified with a margin of 10%.Additionally,the degree of comfort was assessed based on the comfort questionnaire.RESULTS The proportion of patients with a BBPS score of≥6 in group 1 was not significantly different from that in group 2,as demonstrated by intention-to-treat(91.2%vs 91.0%,P=0.953)and per-protocol(91.8%vs 91.0%,P=0.802)analyses.Furthermore,in patients≥75 years in age,the proportion of BBPS scores of≥6 in group 1 was not significantly different from that in group 2(90.9%vs 97.0%,P=0.716).Group 1 had higher comfort scores(8.85±1.162 vs 7.59±1.735,P<0.001),longer sleep duration(6.86±1.204 h vs 5.80±1.730 h,P<0.001),and fewer awakenings(1.42±1.183 vs 2.04±1.835,P=0.026)than group 2.CONCLUSION For hospitalized patients≥50 years in age,the bowel preparation regimen comprising 2-L PEG+30-mL lactulose+a low-residue diet produced a cleanse that was as effective as the 4-L PEG regimen and even provided better comfort. 展开更多
关键词 aged 50 years or older HOSPITALIZED 2-L polyethylene-glycol+30-mL lactulose+a low-residue diet Comfort
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The intrinsic developmental age signal defines an age-dependent climbing behavior in cucumber
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作者 Zezhou Hong Xinrui Wang +7 位作者 Zipei Fan Jiahao Wang Aiyi Yang Guochao Yan Yong He Huasen Wang Zhujun Zhu Yunmin Xu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期797-808,共12页
The tendril is a climbing organ in cucurbits and functions in physical support and to avoid shading by neighboring vegetation.However,how cucurbits produce tendrils to obtain climbing ability is largely unknown.In thi... The tendril is a climbing organ in cucurbits and functions in physical support and to avoid shading by neighboring vegetation.However,how cucurbits produce tendrils to obtain climbing ability is largely unknown.In this study,tendril phenotypes were investigated during different developmental stages.Our results revealed that tendril growth exhibited an age-dependent pattern in cucurbits.Tendril growth was inhibited,and the tendril was formed as a short tendril[nonfunctional tendril(nonF-tendril),approximately 0.1 cm]during the seedling stage.In contrast,enhanced cell proliferation and cell expansion led to rapid elongation of the tendril during the climbing stage,and the tendril formed as a functional tendril(F-tendril,approximately 30 cm)to obtain climbing ability.RT-qPCR detection showed that age-dependent tendril growth correlated negatively with the abundance of the conserved age regulator CsmiR156.Defoliation induced CsmiR156 to inhibit CsSPLs,and F-tendril formation and climbing ability were delayed in defoliated cucumbers,which confirmed the role of CsmiR156 in regulating tendril growth in vivo.Additionally,exogenous gibberellin(GA)treatment showed that GA positively regulated tendril growth,and RT-qPCR detection showed that the GA bio-synthetic genes and metabolic genes were affected by age pathway,suggesting that the age pathway depended on GA bio-synthetic and metabolic pathway to regulate cell expansion to determine tendril growth.In summary,our work reveals that change in tendril type is an important marker of phase transition in cucumber,and tendril growth is regulated by an intrinsic developmental age signal,ensuring that the cucumber obtains climbing ability at a suitable age. 展开更多
关键词 CUCUMBER TENDRIL age CsmiR156 CsSPL Climbing ability
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Can serum immunoglobulin G4 levels and age serve as reliable predictors of relapse in autoimmune pancreatitis?
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作者 Jun-Min Song Si-Yu Sun 《World Journal of Gastroenterology》 SCIE CAS 2024年第5期512-515,共4页
We are writing in response to the paper published in the World Journal of Gastroenterology by Zhou et al.The authors identified higher serum immunoglobulin(Ig)G4 levels and age over 55 years as independent risk factor... We are writing in response to the paper published in the World Journal of Gastroenterology by Zhou et al.The authors identified higher serum immunoglobulin(Ig)G4 levels and age over 55 years as independent risk factors for disease relapse.Despite notable strengths,it is crucial to address potential biases.Firstly,the cohort study included 189 patients with autoimmune pancreatitis(AIP)type 1(with higher IgG4 seropositivity and higher relapse)and 24 with type 2(with lower IgG4 seropositivity and lower relapse).Consequently,most,if not all,AIP type 2 patients were assigned to the normal group,possibly inflating the association of higher serum IgG4 levels with relapse and potentially exaggerating the association of older age with relapse.Secondly,the authors did not provide sufficient details regarding AIP diagnosis,such as the ratio of definitive vs probable cases and the proportion of biopsies.In cases where histological evidence is unavailable or indeterminate,AIP type 2 may be misdiagnosed as definitive type 1,and type 1 may also be misdiagnosed as probable type 2,particularly in cases with normal or mildly elevated serum IgG4 levels.Lastly,in this retrospective study,approximately one-third of the consecutive patients initially collected were excluded for various reasons.Accordingly,the impact of nonrandom exclusion on relapse outcomes should be carefully considered.In conclusion,the paper by Zhou et al offers plausible,though not entirely compelling,evidence suggesting a predictive role of elevated serum IgG4 levels and advanced age in AIP relapse.The foundation for future investigations lies in ensuring a reliable diagnosis and accurate disease subtyping,heavily dependent on obtaining histological specimens.In this regard,endoscopic ultrasound-guided fine-needle biopsy emerges as a pivotal component of the diagnostic process,contributing to mitigating biases in future explorations of the disease. 展开更多
关键词 Autoimmune pancreatitis IMMUNOGLOBULIN Endoscopic ultrasound RELAPSE age
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