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China CDC weekly 2024年第3期6卷 45-50页

作者： Hui Liu Qiyu Zhu Lei zhang Yujing Liu Peng Xu Mengjie Han National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Chinese Association of STD and AIDS Prevention and Control BeijingChina Beijing Chaoyang Kangzhong Health and Education Center BeijingChina

What is already known about this topic?Approximately 80%of newly diagnosed human immunodeficiency virus(HIV)cases among individuals aged 15–24 years in China are attributed to out-ofschool *** is added by this report?This study presents findings on HIV prevalence and comprehensive insights into HIV service utilization,risky behaviors,and prevention knowledge among young out-of-school men who have sex with men(MSM)aged 16–24 years in *** population exhibits a disproportionately high burden of HIV,with only 51.6%of HIV cases previously *** are the implications for public health practice?HIV services should be expanded to include these key *** interventions are needed to remove barriers to regular HIV services faced by young key populations.

关键词： prevention remove expanded

Deep reinforcement learning using least-squares truncated temporal-difference

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 425-439页

作者： Junkai Ren Yixing Lan Xin Xu Yichuan zhang Qiang Fang Yujun Zeng College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina State Key Laboratory of Astronautic Dynamics Xi'an Satellite Control CenterXi'anChina

Policy evaluation(PE)is a critical sub-problem in reinforcement learning,which estimates the value function for a given policy and can be used for policy ***,there still exist some limitations in current PE methods,such as low sample efficiency and local convergence,especially on complex *** this study,a novel PE algorithm called Least-Squares Truncated Temporal-Difference learning(LST2D)is *** LST2D,an adaptive truncation mechanism is designed,which effectively takes advantage of the fast convergence property of Least-Squares Temporal Difference learning and the asymptotic convergence property of Temporal Difference learning(TD).Then,two feature pre-training methods are utilised to improve the approximation ability of ***,an Actor-Critic algorithm based on LST2D and pre-trained feature representations(ACLPF)is proposed,where LST2D is integrated into the critic network to improve learning-prediction *** simulation studies were conducted on four robotic tasks,and the corresponding results illustrate the effectiveness of *** proposed ACLPF algorithm outperformed DQN,ACER and PPO in terms of sample efficiency and stability,which demonstrated that LST2D can be applied to online learning control problems by incorporating it into the actor-critic architecture.

关键词： Deep reinforcement learning policy evaluation temporal difference value function approximation

Publication-level analysis of Journal of Plant Ecology during 2018-2022

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Journal of Plant Ecology 2024年第4期17卷 197-201页

作者： Yu Liao Pu Wang Lijuan Liu Wen-Hao zhang National Science Library Chinese Academy of SciencesBeijing 100190China Center for Documentation and Information Institute of BotanyChinese Academy of SciencesBeijing 100093China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Journal of Plant Ecology(JPE)was established in 2008 and is sponsored by the Botanical Society of China and the Institute of Botany,Chinese Academy of *** by Oxford University Press,UK,JPE encompasses a wide range of article types within the expansive field of plant *** of July 2021,JPE has transitioned to fully Open Access,ensuring unrestricted access to the full text for both readers and *** shift enhances the journal’s role as a crucial platform for plant ecologists worldwide to disseminate their research findings.

关键词： Open Plant Access

Paleo-uplift forced regional sedimentary evolution:A case study of the Late Triassic in the southeastern Sichuan Basin,South China

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Petroleum 2024年第3期10卷 462-473页

作者： Fangyu He Qingsong Cheng Dongtao zhang Yubing Ji Ziying Wang Tenghui Lu PetroChina Zhejiang Oilfield Company Hangzhou 310023China School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500China Sichuan Natural Gas Geology Key Laboratory Southwest Petroleum UniversityChengdu610500China

The sedimentary environment of the Upper Triassic in the southeastern Sichuan Basin is obviously controlled by Luzhou paleo-uplift(LPU).However,the influence of paleo-uplift on the sedimentary patterns of the initial stages of this period in the southeastern Sichuan Basin has not yet been clear,which has plagued oil and gas exploration and *** study shows that there is a marine sedimentary sequence,which is considered to be the first member of Xujiahe Formation(T_(3)X^(1))in the southeastern Sichuan *** development of LPU resulted in the sedimentary differences between the eastern and western Sichuan Basin recording T_(3)X^(1)and controlled the regional sedimentary *** western part is dominated by marine sediments,but the eastern paleo-uplift area is dominated by continental sedimentation in the early stage of T_(3)X^(1),and it begins to transform into a marine sedimentary environment consistent with the whole basin in the late stage of the period recorded by the Xujiahe *** evidences are as follows:(1)time series:based on the cyclostratigraphy analysis of Xindianzi section and Well D2,in the southeastern Sichuan Basin,the period of sedimentation of the Xujiahe Formation is about 5.9 Ma,which is basically consistent with the Qilixia section,eastern Sichuan basin,where the Xujiahe Formation is widely considered to be relatively complete;(2)distribution and evolution of palaeobiology:based on analysis of abundance evolution of major spore-pollen,many land plant fossils are preserved in the lower part of T_(3)X^(1),indicates the sedimentary environment of continental *** the upper part of T_(3)X^(1),the fossil of terrestrial plants decreased,while the fossil of marine and tidal environment appeared,this means that it was affected by the sea water in the late stages of T_(3)X^(1);(3)geochemistry:calculate the salinity of water from element indicates that the uplift area is continental sedimentary environment in the early stage

关键词： Luzhou paleo-uplift Late Triassic Cyclostratigraphy Palynology Sedimentary environment

Combined strategies for improving the heterologous expression of a novel xylanase from Fusarium oxysporum Fo47 in Pichia pastoris

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Synthetic and Systems Biotechnology 2024年第3期9卷 426-435页

作者： Chun Liu Yaping zhang Chunting Ye Fengguang Zhao Yian Chen Shuangyan Han School of Biology and Biological Engineering South China University of TechnologyGuangzhou510640China School of Light Industry and Engineering South China University of TechnologyGuangzhou510640China

Xylanase,an enzyme capable of hydrolyzing non-starch polysaccharides found in grain structures like wheat,has been found to improve the organizational structure of dough and thus increase its *** our past work,one promising xylanase FXYL derived from Fusarium oxysporum Fo47 and first expressed 779.64 U/mL activity in *** has shown significant potential in improving the quality of whole wheat bread,making it become a candidate for development as a new flour *** optimization of expression elements and gene dose,the xylanase activity of FXYL strain carrying three-copies reached 4240.92 U/mL in *** addition,12 factors associated with the three stages of protein expression pathway were co-expressed individually in order in three-copies strain,and the translation factor Pab1 co-expression increased FXYL activity to 8893.53 U/***,combining the most effective or synergistic factors from three stages did not exhibit better results than co-expressing them *** further evaluate the industrial potential,the xylanase activity and protein concentration reached 81184.51 U/mL and 11.8 g/L in a 5 L fed-batch *** engineering strategies improved the expression of xylanase FXYL by more than 104-fold,providing valuable insights for the cost-effective industrial application of FXYL in the baking field.

关键词： Xylanase Pichia pastoris Heterologous protein Secretion expression

Design of multi-section luffing apple pruning equipment and cutting test of the key components

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 109-117页

作者： Siyuan Tong Wenbin Li Yaxiong Wang Lei zhang Feng Kang School of Technology Beijing Forestry UniversityKey Lab of State Forestry and Grassland Administration for Forestry Equipment and AutomationBeijing 100083China

In order to reduce the labor intensity and improve the efficiency of pruning,this study designed a multi-section luffing apple pruning equipment suitable for apple orchards in hilly and mountainous areas of *** the essay,the structure and working principle of the equipment are expounded,the cutter was analyzed,and the parameters were *** the self-made test bench to simulate the field experiment,this study selected the ratio of cutting speed to feeding speed and feeding speed as the influencing factors and took the cut-off rate,cutting efficiency and cutting power as the objectives to carry out single factor experiment and quadratic regression orthogonal *** test results show that the cutting power increases with the increase of ratio of cutting speed to feeding speed,and the cut-off rate and cutting efficiency first increase and then *** the feeding speed increases,the cutting efficiency and power increase,and the cut-off rate *** the cutoff rate was greater than 80%,the optimal combination of operating parameters was the feeding speed of 0.55 m/s and ratio of cutting speed to feeding speed of *** this combination,the cut-off rate was 84.9%,the cutting efficiency was 13.1,and the cutting power was 175.7 *** error between the predicted target value of the model and the average measured target value was less than 7%,so the test results are *** to the obtained optimal operating parameters,the actual cutting experiment of the pruning equipment in the field was carried out,and the cutting rate was 96.3%,which meet the design *** study can also meet the needs of mechanized pruning of fruit trees with different crown shapes,improve the applicability of pruning equipment,and provide support for the development of mechanized pruning equipment in China.

关键词： apple pruning equipment cutting test optimal parameters regression analysis

Conditions for the enrichment of karst hydrothermal resources in Bohai Bay Basin

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Energy Geoscience 2024年第1期5卷 172-183页

作者： Pengwei Li Zhiliang He Zongquan Hu Ying zhang Jianyun Feng Petroleum Exploration and Production Research Institute SINOPECBeijing100083China SINOPEC Beijing100728China

Drilling for karst hydrothermal resources in eastern China has posed challenges,including disparities between the temperature and yield of geothermal *** is evident that relying solely on geothermal anomalies or indications of karst reservoirs is inadequate for the exploration of karst hydrothermal *** study seeks to elucidate the cause of geothermal sweet spots by analyzing the interplay between geothermal anomalies and karst reservoirs and the underlying geological conditions for karst hydrothermal *** findings include:(1)the Bohai Bay Basin has been geologically favorable for the development of karst hydrothermal resources since the Mesozoic era;(2)the karst hydrothermal enrichment varies significantly between the basin’s margin and its *** the basin margin,the enrichment is largely driven by groundwater activity and faults,particularly where faults facilitate the upwelling of geothermal *** contrast,within the basin’s interior,karst hydrothermal resources are predominantly influenced by buried hills and are especially enriched in areas facilitating the discharge of deep geothermal waters.

关键词： Buried hill Karst hydrothermal resources Enrichment regularity Bohai bay basin

N-fixing tree species promote the chemical stability of soil organic carbon in subtropical plantations through increasing the relative contribution of plant-derived lipids

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Forest Ecosystems 2024年第5期11卷 758-769页

作者： Xiaodan Ye Junwei Luan Hui Wang Yu zhang Yi Wang Shirong Liu College of Coastal Agricultural Sciences Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing 100091China Institute of Resources and Environment International Centre for Bamboo and RattanKey Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo&Rattan Science and TechnologyBeijing 100102China

Biodiversity experiments have shown that soil organic carbon(SOC)is not only a function of plant diversity,but is also closely related to the nitrogen(N)-fixing ***,the effect of N-fixing trees on SOC chemical stability is still little known,especially with the compounding effects of tree species *** experimental field manipulation was established in subtropical plantations of southern China to explore the impacts of tree species richness(i.e.,one,two,four and six tree species)and with/without N-fixing trees on SOC chemical stability,as indicated by the ratio of easily oxidized organic carbon to SOC(EOC/SOC).Plant-derived C components in terms of hydrolysable plant lipids and lignin phenols were isolated from soils for evaluating their relative contributions to SOC chemical *** results showed that N-fixing tree species rather than tree species richness had a significant effect on EOC/*** plant lipids and lignin phenols were negatively correlated with EOC/SOC,while hydrolysable plant lipids contributed more to EOC/SOC than lignin phenols,especially in the occurrence of N-fixing *** presence of N-fixing tree species led to an increase in soil N availability and a decrease in fungal abundance,promoting the selective retention of certain key components of hydrolysable plant lipids,thus enhancing SOC chemical *** findings underpin the crucial role of N-fixing trees in shaping SOC chemical stability,and therefore,preferential selection of N-fixing tree species in mixed plantations is an appropriate silvicultural strategy to improve SOC chemical stability in subtropical plantations.

关键词： Tree species diversity Soil organic carbon N-fixing tree species Hydrolysable plant lipids Lignin phenols

Disc-cutter induced rock breakage mechanism for TBM excavation in rock masses with different joint shear strengths

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Underground Space 2024年第6期19卷 119-137页

作者： Bolong Liu Bo Li Liang zhang Rui Huang Huicai Gao Shilin Luo Tao Wang Key Laboratory of Rock Mechanics and Geohazards of Zhejiang Province Shaoxing UniversityShaoxing 312000China College of Civil Engineering Tongji UniversityShanghai 200092China College of Civil and Architectural Engineering Xi’an University of Science and TechnologyXi’an 710054China College of Civil Engineering Changsha UniversityChangsha 410022China School of Transportation Science and Engineering Harbin Institute of TechnologyHarbin 150040China Chongqing Research Institute of Harbin Institute of Technology Harbin Institute of TechnologyChongqing 401151China

When tunnel boring machines(TBMs)excavate through jointed rock masses,the cutting efficiency is strongly affected by the shear strength of joints,the mechanism of which,however,remains poorly *** this study,a series of disc-cutter indentation tests were conducted on granite rock mass specimens with different joint shear *** the indentation,the cracking process was recorded by a digital image correlation(DIC)*** deformation and strength of specimens,cracking behavior,rock breakage mode and cutting efficiency were quantitatively *** addition,to investigate the combined effects of joint shear strength,orientation and spacing on the rock breakage mechanism,numerical rock mass models were established based on a particle flow code *** results reveal that the cracking of primary and secondary cracks changes from the mixed shear-tensile to tensile mode in the initial stage,while the joint shear strength does not affect the cracking mode in the subsequent propagation *** rock breakage mode is classified to an internal block breakage mode,a cross-joint breakage mode and a cutters-dependent breakage *** cross-joint breakage mode is optimal for improving the cutting *** simulation results reveal that the increase in the joint shear strength changes the internal block breakage mode to cross-joint breakage mode for rock masses of particular ranges of joint orientation and *** findings provide basis for improving the TBM cutting efficiency through jointed rock masses.

关键词： Indentation test Joint shear strength Disc cutter Rock breakage mechanism Cutting efficiency

A highly sensitive multiple-mode optical thermometer designed in Eu^(2+/3+)and Li^(+)co-doped polymorphism compound LaSc_(3)(BO_(3))_(4)

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Journal of Advanced Ceramics 2024年第6期13卷 821-833页

作者： Nan Yang Zhuo Li Tingxia Zhou Ziwang zhang Wen Shi Yexiang Tong Jianxin Shi School of Chemistry IGCMESun Yat-sen UniversityGuangzhou 510006China MOE of the Key Laboratory of Bioinorganic and Synthetic Chemistry IGCMEThe Key Lab of Low-Carbon Chemistry&Energy Conservation of Guangdong ProvinceSun Yat-sen UniversityGuangzhou 510006China

Noncontact optical thermometers have attracted widespread attention,but existing problems such as single-mode and low-sensitivity thermometers still urgently need to be ***,a novel multiple-mode thermometer was designed for the polymorphism LaSc_(3)(BO_(3))_(4):Eu^(2+/3+),Li^(+).X-ray diffraction(XRD)patterns revealed a slight transition betweenα-andβ-phases with the concentrations of the dopants,which is further proved by structure refinements and first-principles *** coexistence of Eu^(2+)and Eu^(3+)in the phosphors and their relative percentages were confirmed by X-ray absorption near-edge structure(XANES)*** from appropriate emissions from Eu^(2+)and Eu^(3+)without obvious energy transfer and their opposite changing trends with temperatures under 307 nm excitation,a triple-mode optical thermometer is obtained for this material within the temperature range of 150–450 *** highest sensitivities of 27.65,14.05,and 7.68%·K^(−1)are achieved based on two fluorescence intensity ratio(FIR)modes of Eu^(2+)and Eu^(3+)(5d–4f/^(5)D_(0)–^(7)F_(2,4))and the fluorescence lifetime(FL)mode of Eu^(2+),*** the best of our knowledge,the former is almost the highest in Eu^(2+)and Eu^(3+)co-doped *** results indicate that this material may be used as an excellent multiple-mode optical thermometer.

关键词： phase transition europium(Eu)ions multiple-mode optical thermometer thermal quenching properties fluorescence intensity ratio(FIR) fluorescence lifetime(FL)