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Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects

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Advances in Atmospheric Sciences 2024年第4期41卷 701-716页

作者： Congxi FANG Jinlei CHEN Chaojun OUYANG Lu WANG Changfeng SUN Quan ZHANG jun wen Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China The State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China College of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China

Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate.

关键词： Hengduan Mountains Area normalized difference vegetation index climate change net heat flux downstream effects

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Research progress of slippage characteristic and gas film stability enhancement methods on biomimetic hydrophobic surfaces

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Journal of Hydrodynamics 2024年第1期36卷 87-101页

作者： Meng-zhuo Zhang Hai-bao Hu Liu-zhen Ren Lu-yao Bao jun wen Luo Xie School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China

The biomimetic hydrophobic surface is a potentially efficient underwater drag reduction method and the drag reduction mechanism of this kind of surface comes from the interfacial slippage.For now,it is a hotspot to grasp the slippage characteristic and explore slippage enhancement strategies.This paper not only summarizes our numerical simulation and experimental results of slippage characteristic at the solid-liquid interface(SLI)of hydrophobic surfaces(HS)and the gas-liquid interface(GLI)of superhydrophobic surfaces(SHS)in recent years,but also introduces some innovative methods that can effectively improve the gas film stability and drag reduction effect of SHS.First,we used the molecular dynamics(MD)simulation method to figure out the effect of the solid-liquid interaction strength,the system temperature and the shear rate on the slippage of SLI,and expound their action mechanism from molecular scale.Then,by MD and multibody dissipative particle dynamics(MDPD)method,the slippage behavior at the GLI was studied under the influence of the microstructure size and the flow driving velocity.We proposed a new kind of hybrid slip boundary condition model to describe the slippage characteristic on GLI.In addition,we found through experiment that a three-dimensional backflow will appear on the GLI under the interfacial adsorption of surfactants,and the backflow direction will reverse with the change of GLI morphology.Finally,we put forward the wettability step structure and gas injection method to enhance the stability and drag reduction effect of the gas film on SHS.

关键词： Hydrophobic surface superhydrophobic surface interfacial slip underwater drag reduction

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China stroke surveillance report 2021

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Military Medical Research 2024年第3期11卷 374-399页

作者： wen-jun Tu Long-De Wang 无 Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China School of Public Health Peking UniversityBeijing 100191China Special Writing Group of China Stroke Surveillance Report

Since 2015,stroke has become the leading cause of death and disability in China,posing a significant threat to the health of its citizens as a major chronic non-communicable disease.According to the China Stroke High-risk Population Screening and Intervention Program,an estimated 17.8 million[95%confidence interval(CI)17.6–18.0million]adults in China had experienced a stroke in 2020,with 3.4 million(95%CI 3.3–3.5 million)experiencing their first-ever stroke and another 2.3 million(95%CI 2.2–2.4 million)dying as a result.Additionally,approximately 12.5%(95%CI 12.4%–12.5%)of stroke survivors were left disabled,as defined by a modified Rankin Scale score greater than 1,equating to 2.2 million(95%CI 2.1–2.2 million)stroke-related disabilities in 2020.As the population ages and the prevalence of risk factors like diabetes,hypertension,and hyperlipidemia continues to rise and remains poorly controlled,the burden of stroke in China is also increasing.A large national epidemiological survey initiated by the China Hypertension League in 2017 showed that the prevalence of hypertension was 24.7%;the awareness,treatment,and control rates in hypertensive patients were:60.1%,42.5%,and 25.4%,respectively.A nationally representative sample of the Chinese mainland population showed that the weighted prevalence of total diabetes diagnosed by the American Diabetes Association criteria was 12.8%,suggesting there are 120 million adults with diabetes in China,and the awareness,treatment,and control rates in diabetic patients were:43.3%,49.0%,and 49.4%,respectively.The“Sixth National Health Service Statistical Survey Report in 2018”showed that the proportion of the obese population in China was 37.4%,an increase of 7.2 points from 2013.Data from 1599 hospitals in the Hospital Quality Monitoring System and Bigdata Observatory Platform for Stroke of China(BOSC)showed that a total of 3,418,432 stroke cases[mean age±standard error(SE)was(65.700±0.006)years,and 59.1%were male]were admitted during 2020.Of those,over 80.0%(81.9%)were ischemic

关键词： Stroke Epidemiological characteristics Treatment Prognosis China

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Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： wen-Long Dang Gang Gao Xin-Cai You Ke-Ting Fan jun Wu De-wen Lei wen-jun He Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&Development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu Sag.Crude oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu Sag.These crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep sag.During migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source rocks.These changes might alter source rock evaluations and oil-source correlation.Based on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu Sag.The source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate oil.Source rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped distribution.Furthermore,biomarker composition parameters indicate a higher thermal maturity than in-situ source rocks.Through a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin mudstone.This finding reminds us that the influence of migrated hydrocarbons

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag

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Equivalence between the internal observability and equation

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 89-97页

作者： LIU wen-jun TU Zhi-yu School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China

This paper is concerned with a third order in time linear Moore-Gibson-Thompson equation which describes the acoustic velocity potential in ultrasound wave program.Influenced by the work of Kaltenbacher,Lasiecka and Marchand(Control Cybernet.2011,40:971-988),we establish an observability inequality of the conservative problem,and then discuss the equivalence between the exponential stabilization of a dissipative system and the internal observational inequality of the corresponding conservative system.

关键词： Moore-Gibson-Thompson equation internal observability exponential stability

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Early gastric cancer recurrence after endoscopic submucosal dissection:Not to be ignored!

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 8-12页

作者： Yan Zeng Jian Yang jun-wen Zhang Department of Psychology The Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010China Department of Gastroenterology Changdu People's Hospital of XizangChangdu 854000Tibet Autonomous RegionChina Department of Gastroenterology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

This editorial comments on the article“Efficacy of multi-slice spiral computed tomography in evaluating gastric cancer recurrence after endoscopic submucosal dissection”.We focus on the importance of paying more attention to postendoscopic submucosal dissection(ESD)gastric cancer recurrence in patients with early gastric cancer(EGC)and how to manage it effectively.ESD has been a wellknown treatment and the mainstay for EGC,with the advantages of less invasion and fewer complications when compared with traditional surgical procedures.Despite a lower local recurrence rate after ESD,the problem of postoperative recurrence in patients with EGC has become increasingly non-ignorable with the global popularization of ESD technology and the increasing number of post-ESD patients.

关键词： Early gastric cancer Recurrence Endoscopic submucosal dissection Postoperative Prediction

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Prediction models of burst strength degradation for casing with considerations of both wear and corrosion

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Petroleum Science 2024年第1期21卷 458-474页

作者： Jie-Li Wang wen-jun Huang De-Li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep wells.This paper aims to predict the casing burst strength with considerations of both wear and corrosion.Firstly,the crescent wear shape is simplified into three categories according to common mathematical models.Then,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are obtained.Secondly,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are obtained.At last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is obtained.The results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth growth.The accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded casing.The burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation.

关键词： Deep well Casing integrity Casing wear Casing corrosion Burst strength

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Hole cleaning evaluation and installation spacing optimization of cuttings bed remover in extended-reach drilling

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Petroleum Science 2024年第3期21卷 2005-2022页

作者： Shuo Peng wen-jun Huang De-Li Gao MOE Key Laboratory of Petroleum Engineering China University of Petroleum-Beijing State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-Beijing

In extended-reach or long-horizontal drilling, cuttings usually deposit at the bottom of the annulus. Once cuttings accumulate to a certain thickness, complex problems such as excessive torque and drag, tubing buckling, and pipe stuck probably occur, which results in a lot of non-productive time and remedial operations. Cuttings bed remover can efficiently destroy deposited cuttings in time through hydraulic and mechanical stirring effects. This paper aims to build a method for hole cleaning evaluation and installation spacing optimization of cuttings bed remover to improve the wellbore cleaning effect. Firstly,a Computational Fluid Dynamics approach with Eulerian—Eulerian multiphase model was utilized to investigate the mechanism of cuttings transportation, and a new type of cuttings bed remover was designed. Next, an evaluation method of hole cleaning effect of remover was established. After that, the effects of several drilling parameters on hole cleaning including flow rate of drilling fluid, rotational speed of drillpipe, rate of penetration, wellbore size, rheological property of drilling fluid, and remover eccentricity on the performance of cuttings bed remover were investigated. The results demonstrate that the new type of remover with streamline blade performs better than conventional removers. The efficiency of hole cleaning is greatly improved by increasing the rotational speed of drillpipe, flow rate of drilling fluid, remover eccentricity, and 6 rpm Fann dial reading for drilling fluid. While higher rate of penetration and large wellbore size result in worse hole cleaning. These findings can serve as an important guide for the structure optimization design of cuttings bed remover and installation spacing of removers.

关键词： Extended-reach drilling Drilling hydraulics Cuttings transport Hole cleaning Cuttings bed remover

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Bone block from lateral window-correcting vertical and horizontal bone deficiency in maxilla posterior site:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2109-2115页

作者： Yu-Lan Wang wen-jun Shao Min Wang State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool and Hospital of StomatologyWuhan UniversityWuhan 430079Hubei ProvinceChina Department of Oral Implantology School and Hospital of StomatologyWuhan UniversityWuhan 430079Hubei ProvinceChina

BACKGROUND Lateral window approach for sinus floor lift is commonly used for vertical bone augmentation in cases when the residual bone height is less than 5 mm.However,managing cases becomes more challenging when a maxillary sinus pseudocyst is present or when there is insufficient bone width.In this case,we utilized the bone window prepared during the lateral window sinus lift as a shell for horizontal bone augmentation.This allowed for simultaneous horizontal and vertical bone augmentation immediately after the removal of the maxillary sinus pseudocyst.CASE SUMMARY A 28-year-old female presented to our clinic with the chief complaint of missing upper left posterior teeth.Intraoral examination showed a horizontal deficiency of the alveolar ridge contour.The height of the alveolar bone was approximately 3.6 mm on cone beam computed tomography(CBCT).And a typical well-defined'dome-shaped'lesion in maxillary sinus was observed on CBCT imaging.The lateral bony window was prepared using a piezo-ultrasonic device,then the bony window was fixed to the buccal side of the 26 alveolar ridge using a titanium screw with a length of 10 mm and a diameter of 1.5 mm.The space between the bony window and the alveolar ridge was filled with Bio-Oss,covered with a Bio-Gide collagen membrane,and subsequently sutured.Nine months later,the patient’s bone width increased from 4.8 to 10.5 mm,and the bone height increased from 3.6 to 15.6 mm.Subsequently,a Straumann^(■)4.1 mm×10 mm implant was placed.The final all-ceramic crown restoration was completed four months later,and both clinical and radiographic examinations showed that the implant was successful,and the patient was satisfied with the results.CONCLUSION The bone block harvested from the lateral window sinus lift can be used for simultaneous horizontal bone augmentation acting as a shell for good two-dimensional bone augmentation.

关键词： Sinus lift Lateral window Dental implant Horizontal bone augmentation Case report

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Effect of early stepwise cardiopulmonary rehabilitation on function and quality of life in sepsis patients

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World Journal of Clinical Cases 2024年第4期12卷 729-736页

作者： Ming-Hui Zheng wen-jun Liu Juan Yang Division of Cardiovascular First Ward Departments of Internal Medicine Liyuan HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Department of Respiratory Medicine PuRen Hospital Affiliated to Wuhan University of Science and Technology/Respiratory MedicineWuhan 430000Hubei ProvinceChina Department of Cardiology Huanggang Central HospitalHuanggang 438000Hubei ProvinceChina

BACKGROUND Sepsis,as a non-limiting host infection disease,can be accompanied by serious complications such as organ failure,which seriously threatens patient quality of life.AIM To investigate the effect of early stepwise cardiopulmonary rehabilitation on cardiopulmonary function and quality of life in patients evacuated from mechanical ventilation with sepsis.METHODS A total of 80 patients with sepsis who were hospitalized in our hospital from January 2021 to January 2022 were selected and divided into the observation group(n=40)and the control group(n=40)according to the random number table method.The observation group was treated with early stepwise cardiopulmonary rehabilitation,and the control group was treated with a conventional treatment regimen.Cardiac function indexes(central venous pressure,cardiac troponin I,B-type brain natriuretic peptide),lung function indicators(diaphragmatic mobility,changes in central venous oxygen saturation,oxygenation index),and quality of life(Quality of Life Evaluation Scale)were compared between the two groups after treatment.RESULTS After treatment,the central venous pressure,diaphragm mobility,central venous oxygen saturation,oxygenation index,and Quality of Life Evaluation Scale scores in the observation group were higher than those in the control group,and the differences were statistically significant(P<0.05).The observation group was less than that of the control group for other parameters,and the differences were statistically significant(P<0.05).CONCLUSION Early stepwise cardiopulmonary rehabilitation can effectively enhance cardiac and pulmonary function and improve the quality of life in patients evacuated from mechanical ventilation with sepsis.

关键词： Stepwise cardiopulmonary rehabilitation Sepsis Evacuation of mechanical ventilation Cardiopulmonary function Quality of life

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