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Impacts of climate change and human activities on vegetation dynamics on the Mongolian Plateau, East Asia from 2000 to 2023

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Journal of Arid Land 2024年第8期16卷 1062-1079页

作者： YAN Yujie CHENG Yiben xin Zhiming zhou Junyu zhou Mengyao WANG Xiaoyu School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Experimental Center of Desert Forestry Chinese Academy of ForestryDengkou 015200China Inner Mongolia Dengkou Desert Ecosystem National Observation Research Station National Forestry and Grassland AdministrationDengkou 015200China

The Mongolian Plateau in East Asia is one of the largest contingent arid and semi-arid areas of the *** the impacts of climate change and human activities,desertification is becoming increasingly severe on the Mongolian *** the vegetation dynamics in this region can better characterize its ecological *** this study,based on Moderate Resolution Imaging Spectroradiometer(MODIS)images,we calculated the kernel normalized difference vegetation index(kNDVI)on the Mongolian Plateau from 2000 to 2023,and analyzed the changes in kNDVI using the Theil-Sen median trend analysis and Mann-Kendall significance *** further investigated the impact of climate change on kNDVI change using partial correlation analysis and composite correlation analysis,and quantified the effects of climate change and human activities on kNDVI change by residual *** results showed that kNDVI on the Mongolian Plateau was increasing overall,and the vegetation recovery area in the southern region was significantly larger than that in the northern *** 50.99%of the plateau showed dominant climate-driven effects of temperature,precipitation,and wind speed on kNDVI *** analysis showed that climate change and human activities together contributed to 94.79%of the areas with vegetation *** human activities promoted the recovery of local vegetation,and climate change inhibited vegetation growth in the northern part of the Mongolian *** study provides scientific data for understanding the regional ecological environment status and future changes and developing effective ecological protection measures on the Mongolian Plateau.

关键词： kernel normalized difference vegetation index(kNDVI) human activities climate change partial correlation analysis composite correlation analysis residual analysis Mongolian Plateau

Microphase Separation of Semiflexible Ring Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第2期42卷 267-276,I0011页

作者： Dan-Yan Qin Sheng-Da Zhao Zhi-xin Liu Jing Zhang xing-hua Zhang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the difficult problem of solving the conformation statistics of complex polymers, this study presents a novel and concise conformation statistics theoretical approach based on Monte Carlo and Neural Network method. This method offers a new research idea for investigating the conformation statistics of complex polymers, characterized by its simplicity and practicality. It can be applied to more complex topological structure, more higher degree of freedom polymer systems with higher dimensions, theory research on dynamic self-consistent field theory and polymer field theory, as well as the analysis of scattering experimental data. The conformation statistics of complex polymers determine the structure and response properties of the system. Using the new method proposed in this study, taking the semiflexible ring diblock copolymer as an example, Monte Carlo simulation is used to sample this ring conformation to construct the dataset of polymer. The structure factor describing conformation statistics are expressed as continuous functions of structure parameters by neural network supervised learning. This is the innovation of this work. As an application, the structure factors represented by neural networks were introduced into the random phase approximation theory to study the microphase separation of semiflexible ring diblock copolymers. The influence of the ring's topological properties on the phase transition behavior was pointed out.

关键词： Ring copolymer Diblock copolymers Semiflexible The order-disorder transition

Effect of Al content in molten steel on interaction between MgO-C refractory and SPHC steel

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Journal of Iron and Steel Research International 2024年第4期31卷 838-848页

作者： Fu-bin Gao Fu-ming Wang Xiang Zhang Tian-yu Du xin-hua Wangg School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Handan Iron and Steel Company Hegang GroupHandan 056015HebeiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The effect of Al content in molten steel on the interaction between SPHC steel(0.005-0.068 wt.%Al,and 19×10^(-4)-58×10^(-4)wt.%O)and MgO-C refractory(11.63 wt.%C)was ***-metallic inclusions in the steel were examined at various periods(0,5,15,30,45,and 60 min)as well as the MgO-C interface after 60 min of corrosion at 1600℃.The results show that when MgO-C refractory comes into contact with SPHC steel,the refractory interface consists of three layers arranged from the innermost to the outermost,including the original refractory layer,the dense MgO layer,and the iron infiltration *** carbon in the MgO-C refractories and the Al content in the molten steel undergo a reaction with the MgO in the refractories,resulting in an increase in Mg concentration in the *** Al content in the molten steel from 0.005 to 0.068 wt.%causes a spinel layer to appear at the interface,and the disappearance time of Al_(2)O_(3) inclusions in the steel decreases from 60 to 30 min,while the average MgO content in inclusions ***,controlling the Al content in the molten steel and the smelting duration can help regulate the formation of spinel inclusionsinthe steel.

关键词： MgO-C refractory SPHC steel Inclusion-Spinel Al-killed steel Interfacial reaction

Imaging characteristics and treatment strategies for carotid artery occlusion caused by skull base fracture:Three case reports

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World Journal of Clinical Cases 2024年第15期12卷 2664-2671页

作者： Pei-xin Shangguan Ke-Chun zhou Department of Emergency Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina

BACKGROUND Traumatic internal carotid artery(ICA)occlusion is a rare complication of skull base fractures,characterized by high mortality and disability rates,and poor ***,timely discovery and correct management are crucial for saving the lives of such patients and improving their *** article retrospectively analyzed the imaging and clinical data of three patients,to explore the imaging characteristics and treatment strategies for carotid artery occlusion,combined with severe skull base *** SUMMARY This case included three patients,all male,aged 21,63,and 16 *** underwent plain film skull computed tomography(CT)examination at the onset of their illnesses,which revealed fractures at the bases of their ***,these cases were definitively diagnosed through CT angiography(CTA)*** first patient did not receive surgical treatment,only anticoagulation therapy,and recovered smoothly with no residual limb dysfunction(Case 1).The other two patients both developed intracranial hypertension and underwent decompressive *** of these patients had high intracranial pressure and significant brain swelling postoperatively,leading the family to choose to take him home(Case 2).The other patient also underwent decompressive craniectomy and recovered well postoperatively with only mild limb motor dysfunction(Case 3).We retrieved literature from PubMed on skull base fractures causing ICA occlusion to determine the imaging characteristics and treatment strategies for this type of *** For patients with cranial trauma combined with skull base fractures,it is essential to complete a CTA examination as soon as possible,to screen for blunt cerebrovascular injury.

关键词： Skull base fracture Traumatic internal carotid artery occlusion Blunt cerebrovascular injury Imaging Case report

Relationship among Parkinson’s disease, constipation, microbes, and microbiological therapy

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World Journal of Gastroenterology 2024年第3期30卷 225-237页

作者： xin-Yang Yuan Yu-Sen Chen zhou Liu Department of Neurology Affiliated Hospital of Guangdong Medical UniversityZhanjiang 524000Guangdong ProvinceChina Institute of Neurology Guangdong Key Laboratory of Age-Related Cardiac and Cerebral DiseasesZhanjiang 524000Guangdong ProvinceChina

This comprehensive review elucidates the complex interplay between gut microbiota and constipation in Parkinson’s disease(PD),a prevalent non-motor symptom contributing significantly to patients’morbidity.A marked alteration in the gut microbiota,predominantly an increase in the abundance of Proteobacteria and Bacteroidetes,is observed in PD-related *** treatments,although safe,have failed to effectively alleviate symptoms,thereby necessitating the development of novel therapeutic *** interventions such as prebiotics,probiotics,and fecal microbiota transplantation(FMT)hold therapeutic *** prebiotics improve bowel movements,probiotics are effective in enhancing stool consistency and alleviating abdominal *** shows potential for significantly alleviating constipation symptoms by restoring gut microbiota balance in patients with *** promising developments,the causal relationship between changes in gut microbiota and PD-related constipation remains elusive,highlighting the need for further research in this expanding field.

关键词： Parkinson disease Constipation Gut microbiota Prebiotics Probiotics Fecal microbiota transplantation

Identification and Molecular Characterization of the Alkaloid Biosynthesis Gene Family in Dendrobium catenatum

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 81-96页

作者： Liping Yang xin Wan Runyang zhou Yingdan Yuan College of Horticulture and Landscape Architecture Yangzhou UniversityYangzhouChina Jiangsu Academy of Forestry NanjingChina Jiangsu Yangzhou Urban Forest Ecosystem National Observation and Research Station YangzhouChina

As one of the main active components of Dendrobium catenatum, alkaloids have high medicinal value. The physicochemicalproperties, conserved domains and motifs, phylogenetic analysis, and cis-acting elements of the genefamily members in the alkaloid biosynthesis pathway of D. catenatum were analyzed by bioinformatics, and theexpression of the genes in different years and tissues was analyzed by qRT-PCR. There are 16 gene families,including 25 genes, in the D. catenatum alkaloid biosynthesis pathway. The analysis of conserved domains andmotifs showed that the types, quantities, and orders of domains and motifs were similar among members ofthe same family, but there were significant differences among families. Phylogenetic analysis indicated that thegene family members showed some evolutionary conservation. Cis-acting element analysis revealed that therewere a large number of light-responsive elements and MYB (v-myb avian myeloblastosis viral oncogene homolog)-related elements in these genes. qRT-PCR showed that expressions of gene family members involved in alkaloidsynthesis were different in different years and tissues of D. catenatum. This study provides a theoretical basisfor further exploration of the regulatory mechanisms of these genes in the alkaloid biosynthesis of D. catenatum.

关键词： Dendrobium catenatum gene family alkaloid biosynthesis

Freestanding MoSe_(2)nanoflowers for superior Li/Na storage properties

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Tungsten 2024年第1期6卷 238-247页

作者： Qiao Cu Chao-Qun Shang Guo-Fu zhou xin Wang Guangdong Provincial Key Laboratory of Optical Information Materials South China Normal UniversityGuangzhou 510006China School of Materials Science and Engineering and Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Wuhan Institute of TechnologyWuhan 430205China International Academy of Optoelectronics at Zhaoqing South China Normal UniversityZhaoqing 526060China

MoSe_(2),with high theoretical specific capacity,has attracted a lot of *** remains an open challenge to effectively suppress the irreversible selenium dissolution and rapid capacity decrease induced by severe volume change during ***,we synthesize MoSe_(2)nanoflowers dispersed on one-dimensional(1D)N-doped carbon nanofibers(MoSe_(2)@NCNFs)for use as a freestanding *** this unique structure,the 1D N-doped carbon nanofibers are found to not only enhance the conductivity but also ensure the structural integrity during the Li^(+)/Na^(+)insertion/destraction *** expected,at 2 A·g^(-1),the specific capacity of the MoSe_(2)@NCNFs is maintained at 180 mAh·g^(-1)after 500 cycles when used in lithium storage ***,in the case of sodium storage,at 1 A·g^(-1),the MoSe_(2)@NCNFs shows a capacity of 122mAh·g^(-1)after 500 *** findings suggest that the MoSe_(2)@NCNF electrodes may be a promising candidate for use in reversible Li/Na storage applications.

关键词： Li/Na storage Freestanding electrode MoSe_(2) Electrochemical reaction kinetics Structural integrity

Research progress on temperature field evolution of hot reservoirs under low-temperature tailwater reinjection

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Journal of Groundwater Science and Engineering 2024年第2期12卷 205-222页

作者： xin Wang Guo-qiang zhou Yan-guang Liu Ying-nan Zhang Mei-hua Wei Kai Bian School of Earth science and Engineering Hebei University of EngineeringHandan 056038HebeiChina Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Technology Innovation Center of Geothermal&Hot Dry Rock Exploration and Development Ministry of Natural ResourcesShijiazhuang 050061China Shanxi Key Laboratory for Exploration and Exploitation of Geothermal Resources Taiyuan 030024China Shanxi Geological Engineering Exploration Institute Taiyuan 030024China

This paper focuses on the study of the evolutionary mechanism governing the temperature field of geothermal reservoir under low-temperature tailwater reinjection conditions,which is crucial for the sustainable geothermal energy *** advancing exploitation of geothermal resources deepens,precise understanding of this mechanism becomes paramount for devising effective reinjection strategies,optimizing reservoir utilization,and bolstering the economic viability of geothermal energy *** article presents a comprehensive review of temperature field evolution across diverse heterogeneous thermal reservoirs under low-temperature tailwater reinjection conditions,and analyzes key factors influ-encing this *** evaluates existing research methods,highlighting their strengths and *** study identifies gaps in the application of rock seepage and heat transfer theories on a large scale,alongside the need for enhanced accuracy in field test results,particularly regarding computational effi-ciency of fractured thermal reservoir models under multi-well reinjection *** address these shortcomings,the study proposes conducting large-scale rock seepage and heat transfer experiments,coupled with multi-tracer techniques for field testing,aimed at optimizing fractured thermal reservoir models'computational efficiency under multi-well reinjection ***,it suggests integrat-ing deep learning methods into research *** initiatives are of significance in deepening the understanding of the evolution process of the temperature field in deep thermal reservoirs and enhancing the sustainability of deep geothermal resource development.

关键词： Geothermal reinjection Seepage heat transfer Tracer test Numerical simulation Thermal breakthrough

Evaluation of suitability,adaptability,and reserve potential of construction land on the Qinghai-Tibet Plateau

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Journal of Geographical Sciences 2024年第1期34卷 41-61页

作者： YANG hua XU Yong zhou Kan WANG Lijia XU Lin Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Construction land is the leading carrier of human activities such as production and *** the construction land suitability(CLS)on the Qinghai-Tibet Plateau(QTP)holds significant implications for harmonizing the relationship between ecological protection and human activity and promoting population and industry layout ***,no relevant studies provide a complete CLS assessment of the *** this study,we developed a model-based CLS evaluation framework coupling of pattern and process to calculate the global CLS on the QTP based on a previously developed CLS evaluation ***,using the land-use data of 1990,2000,2010,and 2020,we examined the adaptability of existing construction land(ECL)to the CLS assessment result through the adaptability index and vertical gradient index and further analyzed the limitations of maladaptive construction ***,we calculated the potential area of reserve suitable construction *** article includes four conclusions:(1)The highly suitable,suitable,moderately suitable,marginally suitable,and unsuitable CLS classes cover areas of 0.33×10^(4)km^(2),10.42×10^(4)km^(2),18.06×10^(4)km^(2),24.12×10^(4)km^(2),and 205.29×10^(4)km^(2),*** approximately 11%of the study area on the QTP is suitable for large-scale permanent construction land,and approximately 79.50%of the area is unsuitable under current economic and technological conditions.(2)The ECL adaptability index is 85.16%,85.93%,85.18%,and 78.01%during 1990–2020,respectively,with an average adaptability index exceeding 80%on the *** ECL distribution generally conforms to construction land suitable space characteristics but with a significant spatial difference.(3)From 1990 to 2020,the maladaptive ECL was dominated by rural settlement land,transport land,and special land,with a rapidly increasing proportion of urban and other construction *** maladaptive ECL is constrained by both elevation and slope in the southern Qinghai Pla

关键词： land resource construction land suitability existing construction land adaptability human activity Qinghai-Tibet Plateau