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Prevalence of osteoporotic vertebral fracture among community-dwelling elderly in Shanghai
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作者 Chao Gao Yang Xu +13 位作者 Li Li Wen-Qin Gu Chun-Tao Yi Qiong Zhu Hong-An Gu Bi-Hua Chen Qing-Qing Wang Feng Tang Ju-Liang Xu Jian-Miao Hou Hui-Jiang Song Hui Wang Zhi-Liang Wang Zhen-Lin Zhang 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第14期1749-1751,共3页
To the Editor:Osteoporosis is becoming a common,serious,and costly health problem,which causes over nine million fractures annually worldwide.[1] Currently,osteoporotic fractures are a considerable burden to public he... To the Editor:Osteoporosis is becoming a common,serious,and costly health problem,which causes over nine million fractures annually worldwide.[1] Currently,osteoporotic fractures are a considerable burden to public health services and have fairly high morbidity and mortality.[2] Vertebral fractures are the most common osteoporotic fracture and may lead to a high risk of further fracture and could be prevalent in both females and males.[3] Ling et al[4] and Ms.OS studies[5] evaluated the prevalence of vertebral fractures in Beijing and Hong Kong,respectively.However,our knowledge of the descriptive epidemiology and risk factors for vertebral fracture in China still remains poor. 展开更多
关键词 OSTEOPOROTIC VERTEBRAL fracture AMONG SHANGHAI COMMUNITY-DWELLING ELDERLY
Limited infection by ‘Candidatus Liberibacter asiaticus’ in ‘Valencia’ sweet orange trees in the presence of Citrus tristeza virus 预览
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作者 FU Shi-min Cristina Gouin +1 位作者 ZHOU Chang-yong John S. Hartung 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第10期2284-2293,共10页
Huanglongbing (HLB) is the most destructive disease of citrus and is associated with ‘Candidatus Liberibacter asiaticus’(CLas), a member of the α-proteobacteria. Citrus tristeza virus (CTV) is another pathogen of c... Huanglongbing (HLB) is the most destructive disease of citrus and is associated with ‘Candidatus Liberibacter asiaticus’(CLas), a member of the α-proteobacteria. Citrus tristeza virus (CTV) is another pathogen of citrus with very great historic as well as current importance. Both CLas and CTV are phloem-restricted pathogens. A severe CTV isolate, CTV-B6, and CLas-B232 induce a group of symptoms of phloem dysfunction that overlap, but the mild isolate CTV-B2 does not cause any loss to commercial trees. Prior inoculation and establishment of CLas-B232 did not affect subsequent establishment of either CTV-B2 or CTV-B6, while super infection by CLas-B232 was reduced by prior establishment of CTV-B2 and to a lesser extent by prior infection with CTV-B6. Trees co-infected with CTV-B6 and CLas-B232 developed more severe symptoms, typical of CTV-B6, than either of the two pathogens co-infected with CTV-B2. In this study, we confirmed that CLas established in the rootlets earlier and with higher concentration than in leaves. The distribution of CLas in the plant infected by CLas-B438 alone and with CTV-B2 fits a previously proposed model but CLas was more sporadically distributed in a plant co-infected by CLas and CTV-B2 than in a plant infected by CLas alone. These biological phenomena are aligned with previously analyzed transcriptome data and the study provides a novel idea that mild CTV strains may provide some protection against CLas by limiting its multiplication and spread. The protective effect may be due to opposite regulation of key host defense pathways in response to CTV-B2 and CLas-B438. 展开更多
关键词 HUANGLONGBING PLANT DEFENSE PLANT PROTECTION
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Long-Term Cropping System, Tillage, and Poultry Litter Application Affect the Chemical Properties of an Alabama Ultisol
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作者 Zhongqi HE Irenus A.TAZISONG +3 位作者 Xinhua YIN Dexter B.WATTS Zachary N.SENWO Henry Allen TORBERT 《土壤圈:英文版》 SCIE CAS CSCD 2019年第2期180-194,共15页
Sustainable agricultural practices have been steadily increasing in the last couple of decades. These management practices frequently involve cover crops, less or no-tillage, and organic fertilization. In this study, ... Sustainable agricultural practices have been steadily increasing in the last couple of decades. These management practices frequently involve cover crops, less or no-tillage, and organic fertilization. In this study, we evaluated the effects of cropping systems,tillage and no-tillage, and the application of poultry litter(PL) on selected soil physicochemical properties and soil test nutrients. Soil samples were collected from the topmost surface(0–5 cm) and subsurface(5–10 cm) layers. The general effect trend was PL application > no-tillage > cover crop > cropping type. There were more statistically significant(P ≤ 0.05) correlations between the 18 soil attributes at the topmost surface than at the subsurface. This could be due to the accumulation of external C inputs and nutrients by crop residues and PL application as well as the retaining effects of no-tillage on less mobile nutrient components. Because of their high mobility and volatile nature, total nitrogen(N), ammonia-N(NH4+-N), and nitrate-N(NO3--N) levels varied greatly(high standard deviations), showing no consistent patterns among the treatments. Compared to the soybean cropping system, corn, especially with the wheat cover crop, contributed more to the total carbon(C) and sulfur(S) in the topmost surface soils(0–5 cm). Poultry litter application greatly increased pH, cation exchange capacity(CEC), base saturation, magnesium(Mg), phosphorus(P), calcium(Ca),sodium(Na), potassium(K), manganese(Mn), copper(Cu), and zinc(Zn) in both soil layers. Contrast comparisons revealed that PL application had more of an effect on these soil chemical properties than no-tillage and cropping systems. These results will shed light on developing better nutrient management practices while reducing their runoff potentials. 展开更多
关键词 conventional TILLAGE cover crop Mehlich-3 extraction NO-TILLAGE nutrient management practice organic fertilization SOIL attributes SOIL test nutrients
Endocannabinoid signaling in psychiatric disorders:a review of positron emission tomography studies
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作者 Matthew E.Sloan Caroline W.Grant +2 位作者 Joshua L.Gowin Vijay A.Ramchandani Bernard Le Foll 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第3期342-350,共9页
Endocannabinoid signaling is implicated in an array of psychopathologies ranging from anxiety to psychosis and addiction.In recent years,radiotracers targeting the endocannabinoid system have been used in positron emi... Endocannabinoid signaling is implicated in an array of psychopathologies ranging from anxiety to psychosis and addiction.In recent years,radiotracers targeting the endocannabinoid system have been used in positron emission tomography(PET)studies to determine whether individuals with psychiatric disorders display altered endocannabinoid signaling.We comprehensively reviewed PET studies examining differences in endocannabinoid signaling between individuals with psychiatric illness and healthy controls.Published studies evaluated individuals with five psychiatric disorders:cannabis use disorder,alcohol use disorder,schizophrenia,post-traumatic stress disorder,and eating disorders.Most studies employed radiotracers targeting cannabinoid receptor 1(CB1).Cannabis users consistently demonstrated decreased CB1 binding compared to controls,with normalization following short periods of abstinence.Findings in those with alcohol use disorder and schizophrenia were less consistent,with some studies demonstrating increased CB1 binding and others demonstrating decreased CB1 binding.Evidence of aberrant CB1 binding was also found in individuals with anorexia nervosa and post-traumatic stress disorder,but limited data have been published to date.Thus,existing evidence suggests that alterations in endocannabinoid signaling are present in a range of psychiatric disorders.Although recent efforts have largely focused on evaluating CB1 binding,the synthesis of new radiotracers targeting enzymes involved in endocannabinoid degradation,such as fatty acid amide hydrolase,will allow for other facets of endocannabinoid signaling to be evaluated in future studies. 展开更多
关键词 positron emission tomography CANNABINOID receptors ENDOCANNABINOIDS fatty acid amide hydrolase monoacylglycerol lipases CANNABIS use disorder ALCOHOLISM schizophrenia post-traumatic stress DISORDERS feeding and eating DISORDERS
RNA-seq analysis for soybean cyst nematode resistance of Glycine soja (wild soybean) 预览
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作者 Cuiping Yuan LingZhang +4 位作者 Hongkun Zhao Yumin Wang Xiaodong Liu Yingshan Dong Glen L. Hartman 《Oil Crop Science-中国油料作物学报英文版》 2019年第1期32-46,共15页
To explore genetic resource of wild soybean (Glycine soia. L), RNA-seq was used to investigate cyst nematode resistance of G. soja. Root transcriptome expressions were profiled at 9, 15 and 20 d post inoculation (DPI)... To explore genetic resource of wild soybean (Glycine soia. L), RNA-seq was used to investigate cyst nematode resistance of G. soja. Root transcriptome expressions were profiled at 9, 15 and 20 d post inoculation (DPI) in resistant and susceptible G. soja to SCN (soybean cyst nematode). A total of 1,594 differentially expressed genes (DEGs) were identified in roots infected by SCN compared with non-infected roots. In the resistant accession, 619, 65, and 8 DEGs were detected at 9, 15, and 20 DPI, respectively, while 327, 460 and 115 DEGs were detected at the same sampling point of susceptible accessions. DEGs were enriched in peroxidase gene sets which were involved in response to oxidative stress and oxidation reduction. Two gene families, ZIM transcription factor and WRKY transcription factor were enriched. WRKY transcription factor was only enriched in resista nt accessi on. Moreover, gene expressions of 9 DEGs were validated by qRT-PCR. XLOC_023202, an unknown protein was up regulated more than 5 fold at 9 and 15 DPI in the resistant accession. These results provided an atlas of gene expressions of G. soja in response to SCN infection, and identified candidate DEGs for future research. 展开更多
关键词 G.soja SCN DIFFERENTIAL expression RNA-SEQ CYST NEMATODE
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Suitability and limitations of mesenchymal stem cells to elucidate human bone illness 预览
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作者 Izaskun Mitxitorena Arantza Infante +1 位作者 Blanca Gener Clara I Rodríguez 《世界干细胞杂志:英文版(电子版)》 2019年第9期578-593,共16页
Functional impairment of mesenchymal stem cells(MSCs),osteoblast progenitor cells,has been proposed to be a pathological mechanism contributing to bone disorders,such as osteoporosis(the most common bone disease)and o... Functional impairment of mesenchymal stem cells(MSCs),osteoblast progenitor cells,has been proposed to be a pathological mechanism contributing to bone disorders,such as osteoporosis(the most common bone disease)and other rare inherited skeletal dysplasias.Pathological bone loss can be caused not only by an enhanced bone resorption activity but also by hampered osteogenic differentiation of MSCs.The majority of the current treatment options counteract bone loss,and therefore bone fragility by blocking bone resorption.These socalled antiresorptive treatments,in spite of being effective at reducing fracture risk,cannot be administered for extended periods due to security concerns.Therefore,there is a real need to develop osteoanabolic therapies to promote bone formation.Human MSCs emerge as a suitable tool to study the etiology of bone disorders at the cellular level as well as to be used for cell therapy purposes for bone diseases.This review will focus on the most relevant findings using human MSCs as an in vitro cell model to unravel pathological bone mechanisms and the application and outcomes of human MSCs in cell therapy clinical trials for bone disease. 展开更多
关键词 Mesenchymal stem cells Bone illness Osteoporosis OSTEOGENESIS Osteoanabolic THERAPIES In VITRO CELL models CELL therapy
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Unmanned Aerial Vehicle Control of Major Sugarcane Diseases and Pests in Low Latitude Plateau 预览
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作者 Xiaoyan WANG Rongyue ZHANG +8 位作者 Hongli SHAN Yuanhong FAN Hong XU Pizhong HUANG Zejuan LI Tingying DUAN Ning KANG Wenfeng LI Yingkun HUANG 《农业生物技术:英文版》 CAS 2019年第4期48-51,共4页
This research was aimed at the defects in traditional artificial spraying control method and the problems such as the difficulty in pesticides applying,labor shortage and low operating efficiency in the middle and lat... This research was aimed at the defects in traditional artificial spraying control method and the problems such as the difficulty in pesticides applying,labor shortage and low operating efficiency in the middle and late stage of sugarcane high stalk crops.The aerial pesticide application technology for sugarcane main diseases and pests was systematically developed and demonstrated from the aspects of aircraft type choice,selection of special pesticides and auxiliaries,integration of pesticides and equipment,field operation,technical specifications,and large-scale application organization mode.The UAV model and flight technical parameters suitable for the sugarcane planting area in low-latitude plateau were analyzed,and the optimal agent formulation combination and application technology of the UAV flight control were screened out,and the UAV flight control was applied to the major sugarcane pests and diseases control in the low-latitude plateau in large scale(UAV flight control was popularized and applied to 15 527 hm 2 in 2018).The research results provided mature whole-process technical support for the normalization of the application of the UVA flight control of major sugarcane pests and diseases.The UAV control technology for major sugarcane pests and diseases had the advantages of ultra-low pesticides applying dosage and high operating efficiency,and could effectively solve the problems such as the difficulty in pesticides applying,labor shortage and low operating efficiency in the middle late growth stage of high stalk crops.This technology successfully opened up a simple,efficient and new way for the effective control of major sugarcane pests and diseases,and practically accelerated the process of integrated control and prevention of sugarcane pests and diseases.In addition,this technology had an extremely significant effect on reducing the loss of sugarcane farmers and enterprises caused by the epidemic and outbreak of sugarcane pests and diseases,increasing sugarcane yield and sugar content.At the same ti 展开更多
关键词 Low latitude plateau Sugarcane diseases and pests Unmanned aerial vehicle Prevention and control technology
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Burnout in the emergency department:Randomized controlled trial of an attention-based training program
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作者 Pádraic J. Dunne Julie Lynch +10 位作者 Lucia Prihodova Caoimhe Oleary Atiyeh Ghoreyshi Sharee A. Basdeo Donal J. Cox Rachel Breen Ali Sheikhi Aine Carroll Cathal Walsh Geraldine McMahon Barry White 《结合医学学报:英文版》 CAS CSCD 2019年第3期173-180,共8页
Background:Burnout(encompassing emotional exhaustion,depersonalization and personal accomplishment)in healthcare professionals is a major issue worldwide.Emergency medicine physicians are particularly affected,potenti... Background:Burnout(encompassing emotional exhaustion,depersonalization and personal accomplishment)in healthcare professionals is a major issue worldwide.Emergency medicine physicians are particularly affected,potentially impacting on quality of care and attrition from the specialty.Objective:The aim of this study was to apply an attention-based training(ABT)program to reduce burnout among emergency multidisciplinary team(MDT)members from a large urban hospital.Design,setting,participants and interventions:Emergency MDT members were randomized to either a notreatment control or an in terve ntion group.In tervention group participa nts engaged in a four sessi on(4 h/sessi on)ABT program over 7 weeks with a practice target of 20 min twice-daily.Practice adhere nee was measured using a smart phone application together with a wearable Charge 2 device.Main outcome measures:The primary outcome was a change in burnout,comprising emotional exhaustion,depersonalization and personal achieveme nt.The sec on dary outcomes were cha nges in other psychological and biometric parameters.Results:The ABT program resulted in a significant reduction(P<0.05;T1|one week before intervention]vs T3[follow-up at two mon ths after intervention])in burnout,specifically,emotional exhaustion,with an effect size(probability of superiority)of 59%.Similar reductions were observed for stress(P<0.05)and anxiety(P<0.05).Furthermore,ABT group participants demonstrated significant improvements in heart rate variability,resting heart rate,sleep as well as an in crease in pro-inflammatory cytokine expression.Conclusion:This study describes a positive impact of ABT on emergency department staff bumout compared to a no-treatment control group.Trial registration:ClinicalTrials.gov identifier NCT02887300. 展开更多
关键词 BURNOUT EMOTIONAL EXHAUSTION MEDITATION Healthcare professional Sleep Stress Cytokines CORTISOL Randomized controlled trial
Detection of Huanglongbing (citrus greening) based on hyperspectral image analysis and PCR
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作者 Kejian WANG Dongmei GUO +7 位作者 Yao ZHANG Lie DENG Rangjin XIE Qiang LV Shilai YI Yongqiang ZHENG Yanyan MA Shaolan HE 《农业科学与工程前沿:英文版》 2019年第2期172-180,共9页
Huanglongbing (HLB, citrus greening) is one of the most serious quarantine diseases of citrus worldwide. To monitor in real-time, recognize diseased trees, and efficiently prevent and control HLB disease in citrus, it... Huanglongbing (HLB, citrus greening) is one of the most serious quarantine diseases of citrus worldwide. To monitor in real-time, recognize diseased trees, and efficiently prevent and control HLB disease in citrus, it is necessary to develop a rapid diagnostic method to detect HLB infected plants without symptoms. This study used Newhall navel orange plants as the research subject, and collected normal color leaf samples and chlorotic leaf samples from a healthy orchard and an HLB-infected orchard, respectively. First, hyperspectral data of the upper and lower leaf surfaces were obtained, and then the polymerase chain reaction (PCR) was used to detect the HLB bacterium in each leaf. The PCR test results showed that all samples from the healthy orchard were negative, and a portion of the samples from the infected orchard were positive. According to these results, the leaf samples from the orchards were divided into disease-free leaves and HLB-positive leaves, and the least squares support vector machine recognition model was established based on the leaf hyperspectral reflectance. The effect on the model of the spectra obtained from the upper and lower leaf surfaces was investigated and different pretreatment methods were compared and analyzed. It was observed that the HLB recognition rate values of the calibration and validation sets based on upper leaf surface spectra under 9-point smoothing pretreatment were 100% and 92.5%, respectively. The recognition rate values based on lower leaf surface spectra under the second-order derivative pretreatment were also 100% and 92.5%, respectively. Both upper and lower leaf surface spectra were available for recognition of HLB-infected leaves, and the HLB PCR-positive leaves could be distinguished from the healthy by the hyperspectral modeling analysis. The results of this study show that early and nondestructive detection of HLBinfected leaves without symptoms is possible, which provides a basis for the hyperspectral diagnosis of citrus with HLB. 展开更多
关键词 CITRUS HLB HYPERSPECTRAL identification PCR
Global sensitivity analysis of wheat grain yield and quality and the related process variables from the DSSAT-CERES model based on the extended Fourier Amplitude Sensitivity Test method 预览
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作者 LI Zhen-hai JIN Xiu-liang +2 位作者 LIU Hai-long XU Xin-gang WANG Ji-hua 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第7期1547-1561,共15页
A crop growth model,integrating genotype,environment,and management factor,was developed to serve as an analytical tool to study the influence of these factors on crop growth,production,and agricultural planning.A maj... A crop growth model,integrating genotype,environment,and management factor,was developed to serve as an analytical tool to study the influence of these factors on crop growth,production,and agricultural planning.A major challenge of model application is the optimization and calibration of a considerable number of parameters.Sensitivity analysis(SA) has become an effective method to identify the importance of various parameters.In this study,the extended Fourier Amplitude Sensitivity Test(EFAST) approach was used to evaluate the sensitivity of the DSSAT-CERES model output responses of interest to 39 crop genotype parameters and six soil parameters.The outputs for the SA included grain yield and quality(take grain protein content(GPC) as an indicator) at maturity stage,as well as leaf area index,aboveground biomass,and aboveground nitrogen accumulation at the critical process variables.The key results showed that:(1) the influence of parameter bounds on the sensitivity results was slight and less than the impacts from the significance of the parameters themselves;(2) the sensitivity parameters of grain yield and GPC were different,and the sensitivity of the interactions between parameters to GPC was greater than those between the parameters to grain yield;and(3) the sensitivity analyses of some process variables,including leaf area index,aboveground biomass,and aboveground nitrogen accumulation,should be performed differently.Finally,some parameters,which improve the model’s structure and the accuracy of the process simulation,should not be ignored when maturity output as an objective variable is studied. 展开更多
关键词 global sensitivity analysis DSSAT EFAST wheat yield GRAIN protein content
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Large System Analysis of Downlink C-RAN with Phase Noise and Fronthaul Compression 预览
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作者 Yishi Xue Jun Zhang +2 位作者 Shi Jin Gan Zheng Hongbo Zhu 《中国通信:英文版》 SCIE CSCD 2019年第8期58-71,共14页
This paper studies the effect of phase noise and fronthaul compression on a downlink cloud radio access network(C-RAN), where several remote radio heads(RRHs) are coordinated to communicate with users by a baseband un... This paper studies the effect of phase noise and fronthaul compression on a downlink cloud radio access network(C-RAN), where several remote radio heads(RRHs) are coordinated to communicate with users by a baseband unit(BBU) on the cloud server. In the system, the baseband signals are precoded at BBU, and then compressed before being transmitted to RRHs through capacity-limited fronthaul links which results in the compressive quantization noise. We assume the regularized zero-forcing precoding is performed with an imperfect channel state information and a compression strategy is applied at BBU. The effect of phase noise arising from nonideal local oscillators both at RRHs and users is considered. We propose an approximate expression for the downlink ergodic sum-rate of considered C-RAN utilizing large dimensional random matrix theory in the large-system regime. From simulation results, the accuracy of the approximate expression is validated, and the effect of phase noise and fronthaul compression can be analyzed theoretically based on the approximate expression. 展开更多
关键词 CLOUD radio access network phase noise capacity-limited fronthaul LINKS large dimensional random matrix theory
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Changes in soil organic carbon contents and fractionations of forests along a climatic gradient in China 预览
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作者 Xiaolu Sun Zuoxin Tang +2 位作者 Michael G. Ryan Yeming You Osbert Jianxin Sun 《森林生态系统:英文版》 CSCD 2019年第1期1-12,共12页
Background: Soil organic carbon(SOC) is a large reservoir of terrestrial carbon(C);it consists of different fractions of varying complexity and stability. Partitioning SOC into different pools of decomposability help ... Background: Soil organic carbon(SOC) is a large reservoir of terrestrial carbon(C);it consists of different fractions of varying complexity and stability. Partitioning SOC into different pools of decomposability help better predict the trend of changes in SOC dynamics under climate change. Information on how physical fractions and chemical structures of SOC are related to climate and vegetation types is essential for spatial model ing of SOC processes and responses to global change factors.Method: Soil samples were col ected from multiple representative forest sites of three contrasting climatic zones(i.e. cool temperate, warm temperate, and subtropical) in eastern China. Measurements were made on SOC contents and physical fractions of the 0–20 cm soil layer, and the chemical composition of SOC of the 0–5 cm soil layer, along with measurements and compilation of the basic site and forest stand variables. The long-term effects of temperature, litter inputs, soil characteristics and vegetation type on the SOC contents and factions were examined by means of "space for time substitution" approach and statistical analysis.Result: Mean annual temperature(MAT) varied from 2.1 ℃ at the cool temperate sites to 20.8 ℃ at the subtropical sites. Total SOC of the 0–20 cm soil layer decreased with increasing MAT, ranging from 89.2 g·kg^-1 in cool temperate forests to 57.7 g·kg^-1 in subtropical forests, at an average rate of 1.87% reduction in SOC with a 1 ℃ increase in MAT.With increasing MAT, the proportions of aromatic C and phenolic C displayed a tendency of decreases, whereas the proportion of alkyl C and A/O-A value(the ratio of alkyl C to the sum of O-alkyl C and acetal C) displayed a tendency of increases. Overall, there were no significant changes with MAT and forest type in either the physical fractions or the chemical composition. Based on the relationship between the SOC content and MAT, we estimate that SOC in the top 20 soil layer of forests potentially contribute 6.58–26.3 Pg C globally to the at 展开更多
关键词 Carb on FRACTIONS FOREST soil Global WARMING SOLID-STATE 13C-CPMAS NMR
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Energy Efficiency and Spectrum Efficiency in Underlay Device-to-Device Communications Enabled Cellular Networks 预览
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作者 Yan Cai Yiyang Ni +2 位作者 Jun Zhang Su Zhao Hongbo Zhu 《中国通信:英文版》 SCIE CSCD 2019年第4期16-34,共19页
In this paper,we investigate the energy efficiency and spectrum efficiency,including one-hop device-to-device(D2D)communications mode and two-way amplify-and-forward(AF)relaying D2D communications mode in underlay D2D... In this paper,we investigate the energy efficiency and spectrum efficiency,including one-hop device-to-device(D2D)communications mode and two-way amplify-and-forward(AF)relaying D2D communications mode in underlay D2D communications enabled cellular networks.An analysis of average energy efficiency and spectrum efficiency are developed and closed-form expressions are obtained for two types of D2D communications modes under the effect of Rayleigh fading channel,path loss,and co-channel interference.Analytical results are validated through numerical simulations.Based on the simulation,the effects of the interference,the distance between D2D pair and the position of relay node on the energy efficiency and spectrum efficiency of D2D communications are investigated.The optimal D2D transmission powers of these two modes to maximize the energy efficiency are also investigated. 展开更多
关键词 D2D COMMUNICATIONS energyefficiency SPECTRUM efficiency two-way AMPLIFY-AND-FORWARD RELAYING PROTOCOL
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秦淮河流域土地利用/覆被变化对蒸散量变化的贡献 预览
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作者 秦孟晟 郝璐 +2 位作者 郑箐舟 金楷仑 孙阁 《中国农业气象》 CSCD 北大核心 2019年第5期269-283,共15页
为评估城市化造成的土地利用/覆被类型变化(Land use/cover change,LUCC)对流域尺度蒸散量变化的影响,选取长三角地区秦淮河流域为研究区,基于Landsat系列卫星数据和站点气象数据,构建决策树模型,提取2000年和2013年土地利用/覆被类型数... 为评估城市化造成的土地利用/覆被类型变化(Land use/cover change,LUCC)对流域尺度蒸散量变化的影响,选取长三角地区秦淮河流域为研究区,基于Landsat系列卫星数据和站点气象数据,构建决策树模型,提取2000年和2013年土地利用/覆被类型数据,同时借助SEBAL模型估算研究区四季典型日(春季:2014-05-26、夏季:2013-08-11、秋季:2013-10-14、冬季:2014-01-02)栅格尺度蒸散,探讨2000-2013年秦淮河流域主要土地利用/覆被类型间转化过程对流域尺度日蒸散量变化的贡献。结果表明:(1)相较于2000年,2013年秦淮河流域不透水面增加183.8%,而水稻田、旱地、林地和水域分别减少19.1%、10.7%、12.8%和9.5%。2000-2013年主要土地利用/覆被类型转化方向包括水稻田→不透水面、旱地→不透水面、水稻田→旱地和旱地→水稻田,转化面积分别为208、168、282和232km^2;(2)仅考虑LUCC的影响,对比2000年,2013年研究区流域尺度日蒸散总量在四季典型日分别减少134万、109万、60万和5万m^3。在春、夏、秋三季典型日,水稻田和旱地向不透水面转化过程造成的贡献率分别为-58.5%、-59.5%、-54.4%和-35.1%、-36.3%、-39.8%,负贡献会抵消旱地向水稻田转化过程造成的正贡献(分别为16.8%、16.3%、5.7%),导致春、夏、秋三季典型日流域尺度日蒸散量下降;而在冬季典型日,水稻田向不透水面、旱地向不透水面和水稻田向旱地转化过程造成的负贡献(分别为-48.8%、-20.5%和-31.8%)会抵消旱地向水稻田转化过程造成的正贡献(26.1%),导致冬季典型日流域尺度日蒸散量下降。总体而言,2000-2013年秦淮河流域城市化带来土地利用/覆被的显著变化,使蒸散较高的水稻田和旱地向蒸散较低的不透水面大面积转化,导致流域尺度日蒸散量在四季均呈下降趋势。 展开更多
关键词 蒸散 SEBAL模型 土地利用/覆被变化 秦淮河流域 Landsat卫星影像
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西瓜果肉番茄红素含量及果实相关性状QTL分析 预览
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作者 王超楠 刘识(编译) +4 位作者 高鹏 王学征 Angela R.Davis Abdul Majeed Baloch 栾非时 《中国瓜菜》 CAS 北大核心 2019年第8期223-224,共2页
目的与意义:番茄红素是重要的天然类胡萝卜素,对人体具有保健作用,同时也是红色果肉西瓜中的主要色素,是决定西瓜果实品质的重要因素之一.栽培西瓜较低的DNA多态性阻碍了高质量遗传图谱的构建和番茄红素含量主效QTL的研究.该研究中,笔... 目的与意义:番茄红素是重要的天然类胡萝卜素,对人体具有保健作用,同时也是红色果肉西瓜中的主要色素,是决定西瓜果实品质的重要因素之一.栽培西瓜较低的DNA多态性阻碍了高质量遗传图谱的构建和番茄红素含量主效QTL的研究.该研究中,笔者成功地利用自行开发的CAPS标记构建了一个包含16个连锁群的西瓜遗传连锁图谱,该图谱将有利于西瓜果肉番茄红素含量关键基因确定及其克隆的进一步研究,同时为西瓜果肉番茄红素含量分子育种提供行之有效的分子标记. 展开更多
关键词 番茄红素 QTL分析 果实品质 西瓜 果肉 相关性状 天然类胡萝卜素 DNA多态性
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Formulation of Determining the Gravity Potential Difference Using Ultra-High Precise Clocks via Optical Fiber Frequency Transfer Technique
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作者 Ziyu Shen Wen-Bin Shen +3 位作者 Zhao Peng Tao Liu Shougang Zhang Dingbo Chao 《地球科学学刊:英文版》 SCIE CAS CSCD 2019年第2期422-428,共7页
Based on gravity frequency shift effect predicted by general relativity theory, this study discusses an approach for determining the gravity potential(geopotential) difference between arbitrary two points P and Q by r... Based on gravity frequency shift effect predicted by general relativity theory, this study discusses an approach for determining the gravity potential(geopotential) difference between arbitrary two points P and Q by remote comparison of two precise optical clocks via optical fiber frequency transfer. After synchronization, by measuring the signal’s frequency shift based upon the comparison of bidirectional frequency signals from P and Q oscillators connected with two optical atomic clocks via remote optical fiber frequency transfer technique, the geopotential difference between the two points could be determined, and its accuracy depends on the stabilities of the optical clocks and the frequency transfer comparison technique. Due to the fact that the present stability of optical clocks achieves 1.6×10-18 and the present frequency transfer comparison via optical fiber provides stabilities as high as 10-19 level, this approach is prospective to determine geopotential difference with an equivalent accuracy of 1.5 cm. In addition, since points P and Q are quite arbitrary, this approach may provide an alternative way to determine the geopotential over a continent, and prospective potential to unify a regional height datum system. 展开更多
关键词 GRAVITY FREQUENCY shift OPTICAL fiber FREQUENCY TRANSFER OPTICAL CLOCK GRAVITY potential
EDOA: an efficient delay optimization approach for mixed-polarity Reed-Muller logic circuits under the unit delay model
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作者 Zhenxue HE Limin XIAO +7 位作者 Fei GU Li RUAN Zhisheng HUO Mingzhe LI Mingfa ZHU Longbing ZHANG Rui LIU Xiang WANG 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第5期1102-1115,共14页
Delay optimization has recently attracted signif-icant attention. However, few studies have focused on the delay optimization of mixed-polarity Reed-Muller (MPRM) logic circuits. In this paper, we propose an efficient... Delay optimization has recently attracted signif-icant attention. However, few studies have focused on the delay optimization of mixed-polarity Reed-Muller (MPRM) logic circuits. In this paper, we propose an efficient delay op-timization approach (EDOA) for MPRM logic circuits under the unit delay model, which can derive an optimal MPRM logic circuit with minimum delay. First, the simplest MPRM expression with the fewest number of product terms is ob-tained using a novel Reed-Muller expression simplification approach (RMESA) considering don't-care terms. Second, a minimum delay decomposition approach based on a Huffman tree construction algorithm is utilized on the simplest MPRM expression. Experimental results on MCNC benchmark cir-cuits demonstrate that compared to the Berkeley SIS 1.2 and ABC, the EDOA can significantly reduce delay for most cir-cuits. Furthermore, for a few circuits, while reducing delay, the EDOA incurs an area penalty. 展开更多
关键词 DELAY optimization mixed-polarity Reed-Muller LOGIC CIRCUITS UNIT DELAY model don't-care terms
Cooperative resource allocation in cognitive wireless powered communication networks with energy accumulation and deadline requirements
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作者 Ding XU Qun LI 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第8期141-154,共14页
This study investigates a multi-carrier cognitive wireless powered communication network(CWPCN) with a wirelessly powered primary user(PU). A two-stage cooperative protocol between the PU and the secondary user(SU) is... This study investigates a multi-carrier cognitive wireless powered communication network(CWPCN) with a wirelessly powered primary user(PU). A two-stage cooperative protocol between the PU and the secondary user(SU) is adopted so that the PU can harvest energy from the SU while the SU gains transmission opportunities. It is assumed that the energy harvested by the PU can be accumulated for future usage, and the quality of service of the PU is guaranteed by satisfying the required minimum number of data bits for a given deadline. Herein, we maximize the SU rate by considering the time allocation,subcarrier allocation, and power allocation in both an offline setting(in which the future channel gains are known a priori) and an online setting(in which only the current channel gains are known). In the offline and online schemes, the maximization problem is solved using the block-coordinate descent method and the Lagrange duality method. The effectiveness of the proposed schemes is evaluated and verified via simulation experiments against benchmark schemes. 展开更多
关键词 WIRELESS powered communication networks ENERGY HARVESTING COGNITIVE radio DEADLINE constraint ENERGY accumulation
Twenty-four-hour ambulatory blood pressure changes in older patients with essential hypertension receiving monotherapy or dual combination antihypertensive drug therapy 预览
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作者 Pei-Pei LU Xu MENG +9 位作者 Ying ZHANG Yan-Qi LI Shu WANG Li-Sheng LIU Wen WANG Yu-Ling LI Yu-Qing ZHANG Ai-Hua HU Xian-Liang ZHOU Li-Hong MA 《老年心脏病学杂志:英文版》 SCIE CAS CSCD 2019年第4期354-361,共8页
Objective To evaluate the differences in 24-hour ambulatory blood pressure (BP) in older patients with hypertension treated with the five major classes of antihypertensive drugs,as monotherapy or dual combination ther... Objective To evaluate the differences in 24-hour ambulatory blood pressure (BP) in older patients with hypertension treated with the five major classes of antihypertensive drugs,as monotherapy or dual combination therapy,to improve daytime and nighttime BP control. Methods We enrolled 1920 Chinese community-dwelling outpatients aged ≥ 60 years and compared ambulatory BP values and ambulatory BP control (24-hour BP < 130/80 mmHg;daytime mean BP < 135/85 mmHg;and nighttime mean BP < 120/70 mmHg),as well as nighttime BP dip patterns for monotherapy and dual combination therapy groups. Results Patients’ mean age was 71 years,and 59.5% of patients were women. Calcium channel blockers (CCBs) constituted the most common (60.3% of patients) monotherapy,and renin–angiotensin system (RAS) blockers combined with CCBs was the most common (56.5% of patients) dual combination therapy. Monotherapy with beta-blockers (BB) provided the best daytime BP control. The probabilities of having a nighttime dip pattern and nighttime BP control were higher in patients receiving diuretics compared with CCBs (OR = 0.52,P = 0.05 and OR = 0.41,P = 0.007,respectively). Patients receiving RAS/diuretic combination therapy had a higher probability of having controlled nighttime BP compared with those receiving RAS/CCB (OR = 0.45,P = 0.004). Compared with RAS/diuretic therapy,BB/CCB therapy had a higher probability of achieving daytime BP control (OR = 1.27,P = 0.45). Conclusions Antihypertensive monotherapy and dual combination drug therapy provided different ambulatory BP control and nighttime BP dip patterns. BB-based regimens provided lower daytime BP,whereas diuretic-based therapies provided lower nighttime BP,compared with other antihypertensive regimens. 展开更多
关键词 Aging AMBULATORY blood pressure monitoring ANTIHYPERTENSIVE drugs BETA-BLOCKERS DIURETICS
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Human immunodeficiency virus and hepatotropic viruses comorbidities as the inducers of liver injury progression 预览
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作者 Murali Ganesan Larisa Y Poluektova +1 位作者 Kusum K Kharbanda Natalia A Osna 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第4期398-410,共13页
Hepatotropic viruses induced hepatitis progresses much faster and causes more liver-related health problems in people co-infected with human immunodeficiency virus(HIV).Although treatment with antiretroviral therapy h... Hepatotropic viruses induced hepatitis progresses much faster and causes more liver-related health problems in people co-infected with human immunodeficiency virus(HIV).Although treatment with antiretroviral therapy has extended the life expectancy of people with HIV,liver disease induced by hepatitis B virus(HBV)and hepatitis C virus(HCV)causes significant numbers of non-acquired immune deficiency syndrome(AIDS)-related deaths in coinfected patients.In recent years,new insights into the mechanisms of accelerated fibrosis and liver disease progression in HIV/HCV and HIV/HBV co-infections have been reported.In this paper,we review recent studies examining the natural history and pathogenesis of liver disease in HIV-HCV/HBV co-infection in the era of direct acting antivirals(DAA)and antiretroviral therapy(ART).We also review the novel therapeutics for management of HIV/HCV and HIV/HBV coinfected individuals. 展开更多
关键词 Human IMMUNODEFICIENCY VIRUS HEPATITIS C VIRUS HEPATITIS B VIRUS FIBROSIS Stiffness Treatment
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