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Effect of intravariceal sclerotherapy combined with esophageal mucosal sclerotherapy using small-volume sclerosant for cirrhotic patients with high variceal pressure

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World Journal of Gastroenterology 2015年第9期21卷 2800-2806页

作者： de-Run kong Jin-Guang Wang Chen Chen Fang-Fang Yu Qiong Wu Jian-Ming Xu department of Gastroenterology the First Affiliated Hospital of Anhui Medical University

AIM:To explore the effect of intravariceal-mucosal sclerotherapy using small dose of sclerosant on the recurrence of esophageal ***:We randomly assigned 38 cirrhotic patients with previous variceal bleeding and high variceal pressure(> 15.2 mm Hg) to receive endoscopic variceal ligation(EVL) and combined intravariceal and esophageal mucosal sclerotherapy(combined group) using small-volume *** end-points of the study were rebleeding and recurrence of esophageal ***:During a median follow-up period of 16 mo,varices recurred in 1 patient in the combined group as compared with 7 patients in the EVL group(p =0.045).Rebleeding occurred in 3 patients in the EVL group as compared with 1 patient in the combined group(p=0.687).No patient died in the two *** significant differences were observed between the two groups with respect to serious adverse ***:Intravariceal-mucosal sclerotherapy using small dose of sclerosant is more effective than EVL in decreasing the incidence of variceal recurrence for cirrhotic patients.

关键词： Variceal bleeding Endoscopic variceal ligation End

Assessment of self-reacting bobbin tool friction stir welding for joining AZ31 magnesium alloy at inert gas environment

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Journal of Magnesium and Alloys 2019年第4期7卷 661-671页

作者： prakash kumar Sahu Nikhil p Vasudevan Bipul Das Sukhomay pal department of Mechanical Engineering and IDM Joint Lab Tsinghua UniversityBeijing 100084China Larsen and Toubro Limited HaziraSuratGujarat 394510India department of Mechanical Engineering National Institute of Technology Silchar788010 AssamIndia department of Mechanical Engineering Indian Institute of Technology Guwahati781039 AssamIndia

Research work presented in this study has the primary target of exploring joint attributes of AZ31 magnesium alloys using friction stir welding process with a modified tool referred as bobbin *** of inert and open atmosphere on mechanical properties are evaluated over a wide range of welding speed and tool rotation *** of the research findings from the inert atmosphere bobbin tool were made with the traditional process of friction stir *** results depicted improved joint properties for inert atmosphere *** and intermediate range of tool rotational speed is found to be favorable for bobbin tool friction stir welding without and with an inert medium,*** atmosphere due to inert medium leads to less oxidation of the AZ31 Mg alloy leading to superior joint *** investigations are also made with the aim of evaluating the impact of bobbin tool and inert medium on joint *** each aspect for joining of AZ31 Mg alloy,bobbin tool with inert medium is found to be an effective solution for joining with improved mechanical properties compared to without inert bobbin tool as well as conventional tool friction stir welding.

关键词： Mg FSW Bobbin tool process parameters Mechanical properties Fractography Microstructural characterization

Distribution patterns of fire regime in the pendjari Biosphere Reserve, West Africa

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Journal of Arid Land 2023年第10期15卷 1160-1173页

作者： Omobayo G ZOFFOUN Chabi A M S DJAGOUN EtotépéA SOGBOHOSSOU Laboratory of Applied Ecology(LEA) Faculty of Agronomic SciencesUniversity of Abomey-Calavi(UAC)Cotonou 01 BP 526Benin GeoEnvironmemt and Biodiversity Conservation(GeoEBC)NGO Cotonou 02 BP 775Benin department of Environment Senghor University1 Place Ahmed OrabiA1 Mancheya BP 415Alexandria 21111Egypt

pendjari Biosphere Reserve(pBR),a primary component of the W-Arly-pendjari transboundary biosphere reserve,represents the largest intact wild ecosystem and pristine biodiversity spot in West *** savannah ecosystem has long been affected by fire,which is the main ecological driver for the annual rhythm of life in the *** the fire distribution patterns will help to improve its management plan in the *** study explores the fire regime in the pRB during 2001–2021 in terms of burned area,seasonality,fire frequency,and mean fire return interval(MFRI)by analysing moderate resolution imaging spectroradiometer(MODIS)burned area *** indicated that the fire season in the pBR extends from October to May with a peak in early dry season(November–december).The last two fire seasons(2019–2020 and 2020–2021)recorded the highest areas burned in the pBR out of the twenty fire seasons *** the twenty years period,8.2%of the reserve burned every 10–11 months and 11.5%burned *** largest part of the reserve burned every one to two years(63.1%),while 8.3%burned every two to four years,5.8%burned every four to ten years,and 1.9%burned every ten to twenty *** 1.3%of the entire area did not fire during the whole study *** returned to a particular site every 1.39 a and the annual percentage of area burned in the pBR was 71.9%.The MFRI(MFRIk *** regime must be maintained to preserve the integrity of the *** this context,we suggest applying early fire in tree and woodland savannahs to lower grass height,and late dry season fires every two to three years in shrub savannah to limit the expansion of shrubs and *** propose a laissez-faire system in areas in woodland savannah where the fire frequency is sufficient to allow tree *** findings highlight the utility of remote sensing in defining the geographical and

关键词： fire season fire frequency West African savannah moderate resolution imaging spectroradiometer(MODIS) burned area

Mobility-Aware partial Computation Offloading in Vehicular Networks: A deep Reinforcement Learning Based Scheme

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China Communications 2020年第10期17卷 31-49页

作者： Jianfei Wang Tiejun Lv pingmu Huang p.Takis Mathiopoulos School of Information and Communication Engineering Beijing University of Posts and Telecommunications(BUPT)Beijing 100876China department of Informatics and Telecommunications National and Kapodistrian University of AthensAthens 15784Greece

Encouraged by next-generation networks and autonomous vehicle systems,vehicular networks must employ advanced technologies to guarantee personal safety,reduce traffic accidents and ease traffic *** leveraging the computing ability at the network edge,multi-access edge computing(MEC)is a promising technique to tackle such *** to traditional full offloading,partial offloading offers more flexibility in the perspective of application as well as deployment of such ***,in this paper,we investigate the application of partial computing offloading in-vehicle *** particular,by analyzing the structure of many emerging applications,e.g.,AR and online games,we convert the application structure into a sequential multi-component *** on shortening the application execution delay,we extend the optimization problem from the single-vehicle computing offloading(SVCOp)scenario to the multi-vehicle computing offloading(MVCOp)by taking multiple constraints into account.A deep reinforcement learning(DRL)based algorithm is proposed as a solution to this *** performance evaluation results have shown that the proposed algorithm achieves superior performance as compared to existing offloading mechanisms in deducing application execution delay.

关键词： partial offloading MEC fog computing vehicular networks D2D AR

An analysis of air pollution associated with the 2023 sand and dust storms over China:Aerosol properties and pM_(10) variability

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Geoscience Frontiers 2024年第2期15卷 155-168页

作者： Mikalai Filonchyk Michael p.p.terson Lifeng Zhang Haowen Yan Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China Gansu provincial Engineering Laboratory for National Geographic State Monitoring Lanzhou 730070China department of Geography/Geology University of Nebraska OmahaOmahaNE 68182USA

Every spring,a large part of China is confronted with sand and dust storms(SDS)–mainly originating in the Gobi(including Chinese and Mongolian Gobi)and Taklamakan *** March-April 2023,most of northern,northwestern and northeastern China was struck by three sandstorms that affected an area with more than 500 million *** this study,aerosol optical,microphysical and radiative properties were studied during these SDS events using an integrated approach that combines satellite,terrestrial and re-analysis *** results showed that dusty conditions were observed in most areas north of the Yangtze River(Chang Jiang)with daily average pM_(10)concentrations exceeding 1000 lg/m^(3) in many *** aerosol optical depth(AOD)at 550 nm during three SDS events exceeded a value of 1 throughout nearly the entire northern part of the *** AERONET data obtained from the AOE_Baotou site showed a significant increase in total AOD and a corresponding decrease in AE during the *** single scattering albedo(SSA),asymmetry parameter(ASY),real refractive index(RRI)and imaginary refractive index(IRI)values indicate an abundance of scattering coarse-mode *** radiative forcing(ARF)at top of the atmosphere and at the earth’s surface was nearly always negative during the period and ranged from48.5 to+2.7 Wm^(-2)and from180.8 to66.6 Wm^(-2),resulting in high positive ARF values at ATM(from+63.8 to+132.3 Wm^(-2)).Each of these affects the heating of the atmosphere and cooling on the earth’s *** atmospheric heating rates ranged from 1.8 to 3.7 k day*** formation of these SDS mainly resulted from the passage of cold fronts associated with low pressure systems in the Gobi and Taklamakan deserts,creating conditions for dust to rise into the atmosphere and move further downwind.

关键词： Dust storm pM_(10) Aerosol optical depth Radiative forcing VIIRS AERONET

Anthropogenic Influence on decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s

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Advances in Atmospheric Sciences 2024年第2期41卷 233-246页

作者： Qin SU Buwen DONG Fangxing TIAN Nicholas p.kLINGAMAN Yunnan key Laboratory of Meteorological Disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunming 650500China department of Atmospheric Sciences Yunnan UniversityKunming 650500China National Centre for Atmospheric Science Department of MeteorologyUniversity of ReadingReadingRG66BBUK Geofysisk Institut University of BergenBergen 5007Norway Citadel Investment Group Moor House120 London WallLondonRG66BBUK

The frequency and duration of observed concurrent hot and dry events(Hdes) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in Hde frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of Hdes averaged over China in the present day(pD,1994–2011) is double that in the early period(Ep, 1964–81);the duration of Hdes increases by 60%. Climate experiments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthropogenic forcing to Hde decadal changes over China. Anthropogenic forcing changes can explain 60%–70% of the observed decadal changes,suggesting an important anthropogenic influence on Hde changes over China across the mid-1990s. Single-forcing experiments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of Hdes throughout China. The change in anthropogenic aerosol(AA) emissions significantly decreases the frequency and duration of Hdes over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in Hdes in response to anthropogenic forcing are mainly due to the response of climatological mean surface air temperatures. The contributions from changes in variability and changes in climatological mean soil moisture and evapotranspiration are relatively small. The physical processes associated with the response of Hdes to GHG and AA changes are also revealed.

关键词： concurrent hot and dry events decadal variation greenhouse gases aerosol emissions

Lifetime measurements for some n=2 levels in Be-like S ⅩⅢ

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原子与分子物理学报 2003年第2期20卷 132-134页

作者： LIU H.p. InstituteofModernphysice

Highly ionized Spectra from sulfur obtained at an energy of 80 MeV have been studied in the 19.0～53.0 nm wavelength range. Radiative lifetimes for some n =2 level in Be+-like S ⅩⅢwere measured using he beam-foil time of flight method. The results, using an arbitrarily normalized decay curves analysis, are compared with theoretical predictions and earlier measurement.

关键词：能量辐射能级跃迁离子激发态寿命实验研究分子物理学性质测定

Migration of Biodegradable Organic Matter in Underlying Soils of Household Waste Dumpsites: A Case Study in Abomey-Calavi, Benin

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Journal of Crystallization process and Technology 2018年第1期8卷 18-32页

作者： Metogbe B.Djihouessi Sofiath Onifade Martin p.Aina Hervé E.Labité Francois de paule Codo Laboratoire des Sciences et Techniques de l’Eau(LSTE) Institut National de l’EauUniversitéd’Abomey-Calavi(UAC)CotonouBénin Institut National de l’Eau(INE) Universitéd’Abomey-Calavi(UAC)CotonouBénin

This paper presented the first part of the studies about the development of a tool for groundwater contamination prediction, conducted by the Laboratory of Sciences and Technology of Water (UAC/Benin). The investigation made consisted in estimating the combined effect of retardation factor and biodegradation on migration processes of leachate, in the underlying soils of household waste dumpsites, without active safety barrier. Leachate infiltration tests for different initial conditions were made on soil columns and the breakthrough curves were traced for electrical conductivity, the 5 day biochemical oxygen demand (BOD5) and total kjeldahl nitrogen TkN. A mathematical migration model was developed and solved numerically by finite difference method and implemented with Matlab R2013a. Thus, the calibration of the model was made with electric conductivity data by determining the dispersion coefficient of the studied soils (D = 0.96 cm2/min). Simulations for model verification showed that the established model can perfectly predict the migration of biodegradable organic pollution (BOD5) but did not give conclusive results for the monitoring of nitrogenous organic matter (TkN). The influence of the retardation factor on the migration of biodegradable organic pollutants in soils was linear, while the biodegradation rate of the organic material on migration showed an exponential pattern.

关键词： Waste Dumpsites pollutants Biodegradability Soil Dispersion Column Test Biodegradable Organic pollution Nitrogenous Organic Matter

Analyzing Dominant 13.5 and 27 day periods of Solar terrestrial Interaction:A New Insight into Solar Cycle Activities

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Research in Astronomy and Astrophysics 2022年第8期22卷 63-73页

作者： Rissnalin Syiemlieh Manashee Adhikary prasanta k panigrahi Eeshankur Saikia department of Applied Sciences Gauhati UniversityAssam 781014India Complex photonic Systems MESA+Institute for NanotechnologyUniversity of TwenteP.O.Box 2177500 AE EnschedeThe Netherlands department of physical Sciences Indian Institute of Science Education and ResearchKolkata 741246India

Our analysis presents an explanation of the Sun–Earth coupling mechanism during declining phase of a solar cycle,and how the dominant 13.5 and 27 day periods play roles in the coupling mechanism which led to intense terrestrial magnetic storms during this declining phase compared to the rising phase of a solar ***,it is observed that while the 27 day period gets strongly modulated in the rising phase,the 13.5 day period modulation is more prominent during the declining *** is suggested that out of the 27 and 13.5 day periods of Sun–Earth interaction,the preferred period of modulation happens to be the one which is more dominant for the less random or quieter system participating in the *** is reported for the first time that the 13.5 day period is more prominent in the Sun–Earth interaction during the declining phase of a solar cycle,as it is the most dominant period of Earth's magnetic system,which happens to be more persistent as a dynamical system and hence quieter or more receptive than the Sun.

关键词： (Sun:)solar wind (Sun:)sunspots (Sun:)solar-terrestrial relation (Sun:)activity methods:data analysis