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Estimation and testing of linkages between forest structure and rainfall interception characteristics of a Robinia pseudoacacia plantation on China’s Loess Plateau

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Journal of Forestry Research 2022年第2期33卷 529-542页

作者： Changkun Ma Yi luo Mingan Shao Xiaoxu jia State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xian University of TechnologyXianChina Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China

Understanding the interaction between canopy structure and the parameters of interception loss is essential in predicting the variations in partitioning rainfall and water resources as affected by changes in canopy structure and in implementing water-based management in semiarid forest *** this study,seasonal variations in rainfall interception loss and canopy storage capacity as driven by canopy structure were predicted and the linkages were tested using seasonal filed *** study was conducted in nine 50 m×50 m Robinia pseudoacacia plots in the semiarid region of China’s Loess *** rain-fall,throughfall and stemflow were measured in seasons with and without leaves in 2015 and *** show that measured average interception loss for the nine plots were 17.9% and 9.4% of gross rainfall during periods with leaves (the growing season) and without leaves, respectively. Average canopy storage capacity estimated using an indirect method was 1.3 mm in the growing season and 0.2 mm in the leafless season. Correlations of relative interception loss and canopy storage capacity to canopy variables were highest for leaf/wood area index (LAI/WAI) and canopy cover, fol-lowed by bark area, basal area, tree height and stand density. Combined canopy cover, leaf/wood area index and bark area multiple regression models of interception loss and canopy storage capacity were established for the growing season and in the leafless season in 2015. It explained 97% and 96% of the variations in relative interception loss during seasons with and without leaves, respectively. It also explained 98% and 99% of the variations in canopy storage capacity during seasons with and without leaves, respectively. The empiri-cal regression models were validated using field data col-lected in 2016. The models satisfactorily predicted relative interception loss and canopy storage capacity during seasons with and without leaves. This study provides greater under-standing a

关键词： Rainfall interception loss Canopy storage Canopy structure Regression models China’s Loess Plateau

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Psychoactive Substance Use and the Impact on the AIDS Epidemic Among the MSM Population:a Meta-Analysis—Worldwide,2014-2023

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China CDC weekly 2024年第42期6卷 1086-1092,I0001-I0006页

作者： Donghang luo Jie Xu wei luo National Center for AIDS/STD Control&Prevention Chinese Center for Diseases Control and PreventionBeijingChina

What is already known about this topic?There is a correlation between psychoactive substance use and heightened human immunodeficiency virus(HIV)susceptibility in men who have sex with men(MSM)populations,although the precise impact on transmission risk remains *** is added by this report?In MSM populations,rush poppers and amphetamines are widely used,with rates of 10.91%and 9.97%.In China,rush poppers usage is notably higher at 47.26%.For other regions and coutries,amphetamines(12.86%),rush poppers(3.62%),and GHB(3.34%)are most ***,17%of MSM use psychoactive substances,with higher HIV risk from amphetamines[Odds ratio(OR)3.06]compared to rush poppers(OR 1.51)and general substances(OR 1.76).What are the implications for public health practice?This study supports the idea that targeting specific regions and types of psychoactive substances for reduction among MSM populations can help decrease HIV transmission as well as promote prevention strategies.

关键词： prevention precise Impact

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基于双目视觉和改进YOLOv8n的火灾检测及测距方法

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陕西科技大学学报 2025年第1期43卷 152-160页

作者：刘振董绍江罗家元孙世政潘学娇重庆交通大学机电与车辆工程学院重庆400074

针对火灾检测出现的漏检误检、模型参数量大及定位困难的问题,基于双目视觉和改进YOLOv8n提出了一种轻量化火灾检测及测距方法.通过双目相机拍摄图片,使用改进的检测算法YOLOv8n-AEM和现有的测距算法SGBM进行检测和测距.首先,在主干网... 详细信息

针对火灾检测出现的漏检误检、模型参数量大及定位困难的问题,基于双目视觉和改进YOLOv8n提出了一种轻量化火灾检测及测距方法.通过双目相机拍摄图片,使用改进的检测算法YOLOv8n-AEM和现有的测距算法SGBM进行检测和测距.首先,在主干网络中引入可变核卷积AKConv和EMA注意力机制,通过构建不规则卷积核有效提取火灾的特征;然后,在颈部网络中构建C2f-SCConv模块,通过特征重组降低模型参数,提高检测速度;其次,基于最小点距离改进损失函数,解决火源与光源重叠导致的漏检与误检问题;最后,增加小目标检测头,提高对小火苗的检测能力.实验结果表明,改进后的检测算法P、R、mAP分别为83.6%、76.4%、83.6%,分别提高了2.5%、3.6%、4.8%;参数量和模型大小分别为2.54 M和5.1 MB,分别降低了15.3%和15%;测距精度误差不超过2.5%,证明改进的方法能准确完成火灾的检测及测距.

关键词：火灾检测双目视觉测距 YOLOv8n 轻量化

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Characteristics of nonlinear evolution of wavepackets in boundary layers

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Science China(Physics,Mechanics & Astronomy) 2013年第2期56卷 250-256页

作者： YU Min luo JiSheng LI jia Department of Mechanics Tianjin University

The nonlinear evolution of a finite-amplitude disturbance in a 3-D supersonic boundary layer over a cone was investigated recently by Liu et al. using direct numerical simulation （DNS）. It was found that certain small-scale 3-D disturbances amplified rapidly. These disturbances exhibit the characteristics of second modes, and the most amplified components have a well- defined spanwise wavelength, indicating a clear selectivity of the amplification. In the case of a cone, the three-dimensionality of the base flow and the disturbances themselves may be responsible for the rapid amplification. In order to ascertain which of these two effects are essential, in this study we carried out DNS of the nonlinear evolution of a spanwise localized disturbance （wavepacket） in a flat-plate boundary layer. A similar amplification of small-scale disturbances was observed, suggesting that the direct reason for the rapid amplification is the three-dimensionality of the disturbances rather than the three-dimensional nature of the base flow, even though the latter does alter the spanwise distribution of the disturbance. The rapid growth of 3-D waves may be attributed to the secondary instability mechanism. Further simulations were performed for a wavepacket of first modes in a supersonic boundary layer and of Tollmien-Schlichting （T-S） waves in an incompressible boundary layer. The re- suits show that the amplifying components are in the band centered at zero spanwise wavenumber rather than at a finite spanwise wavenumber. It is therefore concluded that the rapid growth of 3-D disturbances in a band centered at a preferred large spanwise wavenumber is the main characteristic of nonlinear evolution of second mode disturbances in supersonic boundary layers.

关键词： boundary layer wavepacket nonlinear evolution second mode spanwise small-scale disturbance

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Nucleolar histone deacetylases HDT1,HDT2,and HDT3 regulate plant reproductive development

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Journal of Genetics and Genomics 2022年第1期49卷 30-39页

作者： Yu luo Dong-Qiao Shi Peng-Fei jia Yuan Bao Hong-Ju Li wei-Cai Yang State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China

Nucleolus is a membrane-less organelle where ribosomes are assembled, and ribosomal RNAs(r RNAs)transcribed and processed. The assembled ribosomes composed of ribosomal proteins and r RNAs synthesize proteins for cell survival. In plants, the loss of nucleolar ribosomal proteins often causes gametophytically or embryonically lethality. The amount of r RNAs are under stringent regulation according to demand and partially switched off by epigenetic modifications. However, the molecular mechanism for the selective activation or silencing is still unclear, and the transcriptional coordination of r RNAs and ribosomal proteins is also unknown. Here, we report the critical role of three Arabidopsis nucleolar proteins HDT1,HDT2, and HDT3 in fertility and transcription of r DNAs and r RNA processing-related genes through histone acetylation. This study highlights the important roles of transcriptional repression of ribosome biogenesisrelated genes for plant reproductive development.

关键词： Histone deacetylase rRNAs Ribosome Reproductive development

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Graft cholangiopathy: etiology, diagnosis, and therapeutic strategies

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Hepatobiliary & Pancreatic Diseases International 2014年第1期13卷 10-17页

作者： Ying luo Wen-Bin Ji wei-Dong Duan Sheng Ye jia-Hong Dong Department of Hepatobiliary Surgery Chinese PLA General Hospital

BACKGROUND: Graft cholangiopathy has been recognized as a significant cause of morbidity, graft loss, and even mortality in patients after orthotopic liver transplantation. The aim of this review is to analyze the etiology, pathogenesis, diagnosis and therapeutic strategies of graft cholangiopathy after liver transplantation. DATA SOURCE: A PubMed database search was performed to identify articles relevant to liver transplantation, biliary complications and cholangiopathy. RESULTS: Several risk factors for graft cholangiopathy after liver transplantation have been identified, including ischemia/ reperfusion injury, cytomegalovirus infection, immunological injury and bile salt toxicity. A number of strategies have been attempted to prevent the development of graft cholangiopathy, but their efficacy needs to be evaluated in large clinical studies. Non-surgical approaches may offer good results in patients with extrahepatic lesions. For most patients with complex hilar and intrahepatic biliary abnormalities, however, surgical repair or re-transplantation may be required. CONCLUSIONS: The pathogenesis of graft cholangiopathy after liver transplantation is multifactorial. In the future, more efforts should be devoted to the development of more effective preventative and therapeutic strategies against graft cholangiopathy.

关键词： liver transplantation bile ducts complications ischemia/reperfusion injury therapy

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Natural and human-induced decline and spatio-temporal differentiation of terrestrial water storage over the Lancang-Mekong River Basin

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Journal of Geographical Sciences 2025年第1期35卷 112-138页

作者： CHEN Junxu WANG Yuan ZHAO Zhifang FAN Yunjiang luo Xiaochuan YI Lu FENG Siqi YANG Liang Emlyn Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Yunnan University International Joint Research Center for Karstology Yunnan University School of Engineering Westlake University Department of Geography Ludwig Maximilian University of Munich (LMU)

Due to water conflicts and allocation in the Lancang-Mekong River Basin(LMRB), the spatio-temporal differentiation of total water resources and the natural-human influence need to be clarified. This work investigated LMRB's terrestrial water storage anomaly(TWSA) and its spatio-temporal dynamics during 2002–2020. Considering the effects of natural factors and human activities, the respective contributions of climate variability and human activities to terrestrial water storage change(TWSC) were separated. Results showed that:(1) LMRB's TWSA decreased by 0.3158 cm/a.(2) TWSA showed a gradual increase in distribution from southwest of MRB to middle LMRB and from northeast of LRB to middle LMRB. TWSA positively changed in Myanmar while slightly changed in Laos and China. It negatively changed in Vietnam, Thailand and Cambodia.(3) TWSA components decreased in a descending order of soil moisture, groundwater and precipitation.(4) Natural factors had a substantial and spatial differentiated influence on TWSA over the LMRB.(5) Climate variability contributed 79% of TWSC in the LMRB while human activities contributed 21% with an increasing impact after 2008. The TWSC of upstream basin countries was found to be controlled by climate variability while Vietnam and Cambodia's TWSC has been controlled by human activities since 2012.

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Variation of soil-plant-atmosphere continuum stable isotope and water source in Qinghai spruce forest of the eastern Qilian Mountains

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Journal of Mountain Science 2023年第2期20卷 355-366页

作者： ZHOU Jun-ju WANG Xue MA luo luo Chu-yu TANG Hai-tao GUO Zhao-nan CHEN jia-wei SHI Su-han SHI wei wei wei ZHANG Dong-xia LIU Chun-fang College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Lanzhou 730070China Sate Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Understanding the hydrogen and oxygen stable isotope composition and characteristics of different water bodies in soil-plant-atmosphere continuum is of significance for revealing regional hydrological processes and water cycle *** this study,we analyzed the stable isotopic composition,relationship and indicative significance of precipitation,soil water(0~100 cm depth)and xylem water of Qinghai spruce(Picea crassifolia)forest in the eastern Qilian Mountains,and explored the circulation process among different water *** results show that the stable isotopes of precipitation vary greatly during the entire observation *** values ofδ2H andδ^(18)O in the precipitation in the warm season are richer than those in the cold season,and the slope and intercept of local meteoric water line(LMWL,δ2H=6.79δ18O+7.13)are both smaller than global meteoric water line(GMWL,δ2H=8.17δ18O+10.56).The stable isotopes of soil water at different depths underwent different degrees of evaporative fractionation,and theδ18O andδ2H of shallow soil water varied greatly,while the deep soil water tended to be *** topsoil(0~10 cm)can respond quickly to precipitation,and the response of the deep soil has a time *** the whole growing season,0~30 cm and 60~100 cm soil water are the main water sources of Qinghai *** water source of Qinghai spruce was from all soil layers in May and September,mainly from the shallow soil layer(0~30 cm)in August and October,and mainly from the deep soil layer(60~100 cm)in June and July.

关键词： Stable hydrogen isotope Stable oxygen isotope Soil-plant-atmosphere continuum SPAC Plant water use IsoSource model

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Characteristics of gas explosion flow fields in complex pipelines

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International Journal of Mining Science and Technology 2015年第1期25卷 157-164页

作者： Zhu Zhao jia Zhenyuan luo Haizhu School of Mechanical Engineering Dalian University of Technology Shenyang Branch China Coal Research Institute

The explosion flow field in five straight pipes with different diameters and one bending pipe selected from a domestic coal mine are studied by the method of numerical simulation. And the results show that,both in the straight and bending pipes, the pressure wave and velocity wave are accelerated by the rising of reaction rate. As the explosion progressed, with the temperature reaching approximately 3000 K, only one pressure wave and one reaction rate wave were observed, while several velocity waves were *** larger diameter presented the highest relative pressure as well as the largest velocity increase and subsequent decrease inside the tube. The bent pipes caused both turbulence and kinetic energy to increase, resulting in the acceleration of the reaction rate. The burning time was 7.4% shorter than the burning time observed for the straight pipe. Based on these results, designing one explosion resistance device, and in the practical engineering applications, it was to be proved to meet the security requirements fully.

关键词： ExplosionNumerical simulationAccelerationReaction rate

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Serum tumor markers for detection of hepatocellular carcinoma

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World Journal of Gastroenterology 2006年第8期12卷 1175-1181页

作者： Lin Zhou jia Liu Feng luo Division of Biotherapy for Cancer Cancer Center West China Hospital'ofSichuan University Chengdu 610041 Sichuan Province China Cancer Center West China Hospital of Sichuan University Chengdu 610041 Sichuan Province China

Hepatocellular carcinoma （HCC） is one of the most frequent malignant tumors and is the second most common cause of cancer death in China. Therefore, it is very important to detect this disease and the recurrence at its earlier period. Serum tumor markers, as the effective method for detecting hepatocellular carcinoma for a long time, could be divided into 4 categories： oncofetal antigens and glycoprotein antigens; enzymes and isoenzymes; genes; and cytokines. Serum alpha fetoprotein （AFP） is the most widely used tumor marker in detecting patients with hepatocellular carcinoma, and has been proven to have capability of prefiguring the prognosis. However, it has been indicated that AFP-L3 and DCP excel AFP in differentiating hepatocellular carcinoma from nonmalignant hepatopathy and detecting small hepatocellular carcinoma. Some tumor markers, such as human cervical cancer oncogene and human telomerase reverse transcriptase mRNA, have also been indicated to have higher accuracies than AFP. Furthermore, some other tumor markers, such as glypican-3, gamma-glutamyl transferase Ⅱ, alpha-Ifucosidase, transforming growth factor-beta1, tumorspecific growth factor, have been indicated to be available supplementaries to AFP in the detection. AFP mRNA has been shown to correlate with the metastasis and recurrence of HCC, and it may be the most useful marker to prefigure the prognosis. Some other markers, such as gamma-glutamyl transferase mRNA, vascular endothelial growth factor, and interleukin-8, could also be used as available prognostic indicators, and the simultaneous determination of AFP and these markers may detect the recurrence of HCC at its earlier period.

关键词： Hepatocellular carcinoma Serum tumor markers Sensitivity Specificity Prognosis

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