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Exploring the mechanism of moist exposed burn ointment for the treatment of diabetic ulcer based on network pharmacology and molecular docking
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作者 YANG Ya-liang GE Xing-yue +3 位作者 LI Wen-wu ZHU Shi-lin YAO Ming-zhe TANG Qian-li 《Journal of Hainan Medical University》 CAS 2023年第22期39-47,共9页
Objective:To discuss the main active components and potential mechanisms of moist burn ointment in the treat-ment of diabetic ulcer were discussed by network pharmacology and molecular docking technology.Methods:Based... Objective:To discuss the main active components and potential mechanisms of moist burn ointment in the treat-ment of diabetic ulcer were discussed by network pharmacology and molecular docking technology.Methods:Based on the TC-MSP database,the main active components and targets of MEBO were screened.The targets related to diabetic ulcers were searched from GeneCards,OMIM,PharmGkb,TTD,and DrugBank databases.The STRING 11.5 database was used to con-struct a protein-protein interaction(PPI)network to screen the core targets.The'drug-target-disease'network diagram was made in Cytoscape 3.8.2 software to screen the core active components.GO enrichment analysis and KEGG pathway enrichment analysis were performed using R language software.Finally,molecular docking was used to preliminarily verify the screening results.Results:A total of 37 active components of MEBO were screened to map 100 targets,5527 targets for diabetic ulcer dis-ease,and 77 intersection targets.PPI network topology analysis suggested that TP53,TNF,HSP90AA1 and other targets were key targets;the network diagram of ‘drug-target-disease’showed that acacetin,wogonin,quercetin,and rutaecarpine were the core active ingredients.GO function analysis mainly involved angiogenesis,ion transport,diameter regulation,cytokine receptor binding,and other processes.KEGG enrichment analysis mainly included PI3K-Akt,AGE-RAGE,and other signaling pathways.Molecular docking showed that the core active ingredients and key targets had good docking activity.Conclusion:The treatment of diabetic ulcer with MEBO is the result of multi-component,multi-target,and synergistic regulation,which provides a theoretical basis for the clinical application of MEBO and the treatment of diabetic ulcer. 展开更多
关键词 Network pharmacology Molecular docking moist exposed burn ointment Diabetic ulcers
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Assessment of Several Moist Adiabatic Processes Associated with Convective Energy Calculation 被引量:7
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作者 李耀东 高守亭 刘健文 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第6期941-950,共10页
Several methods dealing with the moist adiabatic process are described in this paper. They are based on static energy conservation, pseudo-equivalent potential temperature conservation, the strict pseudo- adiabati... Several methods dealing with the moist adiabatic process are described in this paper. They are based on static energy conservation, pseudo-equivalent potential temperature conservation, the strict pseudo- adiabatic equation, and the reversible moist adiabatic process, respectively. Convective energy parame- ters, which are closely related to the moist adiabatic process and which re?ect the gravitational e?ects of condensed liquid water, are reintroduced or de?ned, including MCAPE [Modi?ed-CAPE (convective avail- able potential energy)], DCAPE (Downdraft-CAPE), and MDCAPE (Modi?ed-Downdraft-CAPE). Two real case analyses with special attention given to condensed liquid water show that the selection of moist adiabatic process does a?ect the calculated results of CAPE and the gravitational e?ects of condensed liq- uid water are not negligible in severe storms. Intercomparisons of these methods show that static energy conservation is consistent with pseudo-equivalent potential temperature conservation not only in physical properties but also in calculated results, and both are good approximations to the strict pseudo-adiabatic equation. The lapse rate linked with the reversible moist adiabatic process is relatively smaller than that linked with other moist adiabatic processes, especially when considering solidi?cation of liquid water in the reversible adiabatic process. 展开更多
关键词 moist adiabatic processes modified convective available potential energy downdraft con-vective available potential energy modified downdraft convective available potential energy reversible moist adiabatic process liquid water
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External Heat Transfer in Moist Air and Superheated Steam for Softwood Drying 被引量:2
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作者 PANGShusheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第6期762-766,共5页
In kiln drying of softwood timber, external heat and moisture mass transfercoefficients are important in defining boundary temperature and moisture content at the woodsurface. In addition, superheated steam drying of ... In kiln drying of softwood timber, external heat and moisture mass transfercoefficients are important in defining boundary temperature and moisture content at the woodsurface. In addition, superheated steam drying of wood is a promising technology but this has notbeen widely accepted commercially, partially due to the lack of understanding of the dryingphenomena occurred during drying. In this work, experimental investigation was performed to quantifythe heat transfer between wood surface and surrounding moist air or superheated steam. In theexperiment, saturated radiata pine sapwood samples were dried using dry-bulb/wet-bulb temperaturesof 60℃/50℃, 90℃/60℃, 120℃/70℃, 140℃/90℃, 160℃/90℃, 140℃/100℃ and 160℃/100℃. The lasttwo schedules were for superheated steam drying as the wet-bulb temperature was set at 100℃. Thecirculation velocity over the board surface was controlled at 4.2m·s^(-1). Two additional runs(90℃/60℃) using air velocities of 2.4 m·s^(-1) and 4.8 m·s^(-1) were performed to check theeffect of the circulation velocity. During drying, sample weight and temperatures at wood surfaceand different depths were continuously measured. Prom these measurements, changes in woodtemperature and moisture content were calculated and external heat-transfer coefficient wasdetermined for both the moist air and the superheated steam drying. 展开更多
关键词 wood drying external heat transfer coefficient moist air moisture content softwood timber superheated steam
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Diagnosis of Moist Vorticity and Moist Divergence for a Heavy Precipitation Event in Southwestern China 被引量:1
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作者 Gang LI Daoyong YANG +2 位作者 Xiaohua JIANG Jing PAN Yanke TAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第1期88-100,共13页
A regional heavy precipitation event that occurred over Sichuan Province on 8-9 September 2015 is analyzed based on hourly observed precipitation data obtained from weather stations and NCEP FNL data. Two moist dynami... A regional heavy precipitation event that occurred over Sichuan Province on 8-9 September 2015 is analyzed based on hourly observed precipitation data obtained from weather stations and NCEP FNL data. Two moist dynamic parameters, i.e., moist vorticity (mζ and moist divergence (mδ), are used to diagnose this heavy precipitation event. Results show that the topography over southwestern China has a significant impact on the ability of these two parameters to diagnose precipitation. When the impact of topography is weak (i.e., low altitude), rn( cannot exactly depict the location of precipitation in the initial stage of the event. Then, as the precipitation develops, its ability to depict the location improves significantly. In particular, m( coincides best with the location of precipitation during the peak stage of the event. Besides, the evolution of the m( center shows high consistency with the evolution of the precipitation center. For mδ, although some false-alarm regions are apparent, it reflects the location of precipitation almost entirely during the precipitation event. However, the mδ center shows inconsistency with the precipitation center. These results suggest that both m( and mδ have a significant ability to predict the location of precipitation. Moreover, m( has a stronger ability than mδ in terms of predicting the variability of the precipitation center. However, when the impact of topography is strong (i.e., high altitude), both of these two moist dynamic parameters are unable to depict the location and center of precipitation during the entire precipitation event, suggesting their weak ability to predict precipitation over complex topography. 展开更多
关键词 moist vorticity moist divergence heavy precipitation southwestern China
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Moist Potential Vorticity Vector for Diagnosis of Heavy Rainfall Events in Tanzania 被引量:1
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作者 Philbert Modest Luhunga George Djolov Edmund Mutayoba 《Journal of Geoscience and Environment Protection》 2016年第9期128-145,共18页
In this paper, we modify the convective vorticity vector (CVV) defined as a cross product of absolute vorticity and gradient of equivalent potential temperature to moist potential vorticity vector (MPVV) defined as a ... In this paper, we modify the convective vorticity vector (CVV) defined as a cross product of absolute vorticity and gradient of equivalent potential temperature to moist potential vorticity vector (MPVV) defined as a cross product of absolute vorticity () and the gradient of the moist-air entropy potential temperature ().  The patterns of (MPVV) are compared with the patterns of heavy rainfall events that occurred over different regions in Tanzania on 20<sup>th</sup> to 22<sup>nd</sup> December, 2011 and on 5<sup>th</sup> to 8<sup>th</sup> May, 2015. Moreover, the article aimed at assessing the relative contributions of the magnitude, horizontal and vertical components of (MPVV) detecting on the observed patterns of rainfall events. Dynamic and thermodynamic variables: wind speed, temperature, atmospheric pressure and relative humidity from numerical output generated by the Weather Research and Forecasting (WRF) model running at Tanzania Meteorological Agency (TMA) were used to compute MPVV. It is found that MPVV provide accurate tracking of locations received heavy rainfall, suggesting its potential use as a dynamic tracer for heavy rainfall events in Tanzania.  Finally it is found that the first and second components of MPVV contribute almost equally in tracing locations received heavy rainfall events. The magnitude of MPVV described the locations received heavy rainfall events better than the components. 展开更多
关键词 moist Potential Vorticity Vector moist-Air Entropic Potential Temperature Heavy Rainfall Events
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THE CALCULATING EQUATIONS OF THE THERMOPHYSICAL PARAMETERS OF THE MOIST AIR AT HIGH TEMPERATURE
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作者 张静波 刘刚 《Journal of China Textile University(English Edition)》 EI CAS 1997年第1期62-67,共6页
By using compression factors of real gas and the Vilia equations and considering the variation of the thermophysical parameters of the mois air with its temperature, this paper develops the calculating equations of th... By using compression factors of real gas and the Vilia equations and considering the variation of the thermophysical parameters of the mois air with its temperature, this paper develops the calculating equations of the thermophysical para leters of the moist air at high temperature ranging from 100℃- 200℃. It is convenient to calculate the thermophysical parameters and the thermophysical processes of the moist air at high temperature. 展开更多
关键词 enthalpy-moisture DIAGRAM t high temperature thermophysical parameters the moist air
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Impacts of Cloud-Induced Mass Forcing on the Development of Moist Potential Vorticity Anomaly During Torrential Rains 被引量:20
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作者 高守亭 周玉淑 +1 位作者 崔晓鹏 戴国平 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第6期923-927,共5页
The impacts of cloud-induced mass forcing on the development of the moist potential vorticity (MPV) anomaly associated with torrential rains are investigated by using NCEP/NCAR 1? × 1? data. The MPV ten... The impacts of cloud-induced mass forcing on the development of the moist potential vorticity (MPV) anomaly associated with torrential rains are investigated by using NCEP/NCAR 1? × 1? data. The MPV tendency equation with the cloud-induced mass forcing is derived, and applied to the torrential rain event over the Changjiang River-Huaihe River Valleys during 26–30 June 1999. The result shows that positive anomalies are located mainly between 850 hPa and 500 hPa, while the maximum MPV, maximum positive tendency of the MPV, and maximum surface rainfall are nearly collocated. The cloud-induced mass forcing contributes to the positive tendency of the moist potential vorticity anomaly. The results indicate that the MPV may be used to track the propagation of rain systems for operational applications. 展开更多
关键词 torrential rain cloud-induced mass forcing moist potential vorticity anomaly
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Diagnostic Analyses and Application of the Moist Ageostrophic Vector Q 被引量:16
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作者 姚秀萍 于玉斌 寿绍文 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第1期96-102,共7页
Considering the main thermal forcing factor, which is critical for the development of synoptic systems, the concept of the moist ageostrophic vector Q is introduced. A formula of the moist ageostrophic Q and the ageos... Considering the main thermal forcing factor, which is critical for the development of synoptic systems, the concept of the moist ageostrophic vector Q is introduced. A formula of the moist ageostrophic Q and the ageostrophic diabatic equation, in which the divergence of the moist ageostrophic Q is taken as a single forcing term, is derived. Meanwhile, the moist ageostrophic Q is applied to diagnose a torrential rain process in North China. The results suggest that the moist ageostrophic Q can clearly reveal the system development during the torrential rain process; the corresponding relationship between the divergence of the moist ageostrophic Q and the rainfall area is better than that of the vertical velocity (w) and the divergence of the dry Q; the 6-h rainfall region can be correctly drawn according to the negative area of the divergence of the moist ageostrophic Q, and its precipitation is positively correlated to the magnitude of the divergence of the moist ageostrophic Q. The research provides valuable information for improving short-term weather forecast. 展开更多
关键词 moist ageostrophic Q diabatic heating effect torrential rain
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Study on Moist Potential Vorticity and Symmetric Instabilityduring a Heavy Rain Event Occurred inthe Jiang-Huai Valleys 被引量:15
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作者 寿绍文 李耀辉 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第2期314-321,共8页
In the light of the theory on moist potential vorticity (MPV) investigation was undertaken of the 700 hPa vertical (horizontal) component MP1 (MPV2) for the heavy rain event occurring in July 5–6, 1991. Results show ... In the light of the theory on moist potential vorticity (MPV) investigation was undertaken of the 700 hPa vertical (horizontal) component MP1 (MPV2) for the heavy rain event occurring in July 5–6, 1991. Results show that the distribution features of the two components were closely related to the development of a mesoscale cyclone as a rainstorm-causing weather system in the lower troposphere in such a way that the ambient atmosphere of which MPV1 > 0 and MPV2 < 0 with |MPV1| ≥ |MPV2| favored the genesis of conditional symmetric instability (CSI) and that, as indicated by calculations, a CSI sector was really existent in the lower troposphere during the heavy rain happening and contributed greatly to its development. 展开更多
关键词 Heavy rain moist potential vorticity (MPV) Conditional symmetric instability
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Diagnosis of a Moist Thermodynamic Advection Parameter in Heavy-Rainfall Events 被引量:11
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作者 吴贤笃 冉令坤 楚艳丽 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第4期957-972,共16页
A moist thermodynamic advection parameter, defined as an absolute value of the dot product of hori- zontal gradients of three-dimensional potential temperature advection and general potential temperature, is introduce... A moist thermodynamic advection parameter, defined as an absolute value of the dot product of hori- zontal gradients of three-dimensional potential temperature advection and general potential temperature, is introduced to diagnose frontal heavy rainfall events in the north of China. It is shown that the parameter is closely related to observed 6-h accumulative surface rainfall and simulated cloud hydrometeors. Since the parameter is capable of describing the typical vertical structural characteristics of dynamic, thermodynamic and water vapor fields above a strong precipitation region near the front surface, it may serve as a physical tracker to detect precipitable weather systems near to a front. A tendency equation of the parameter was derived in Cartesian coordinates and calculated with the simulation output data of a heavy rainfall event. Results revealed that the advection of the parameter by the three-dimensional velocity vector, the covariance of potential temperature advection by local change of the velocity vector and general potential temperature, and the interaction between potential temperature advection and the source or sink of general potential temperature, accounted for local change in the parameter. This indicated that the parameter was determined by a combination of dynamic processes and cloud microphysical processes. 展开更多
关键词 moist thermodynamic advection parameter potential temperature advection general potential temperature heavy rainfall event
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Soil Microbial Population Dynamics along a Chronosequence of Moist Evergreen Broad-leaved Forest Succession in Southwestern China 被引量:10
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作者 ZHU Wanze CAI Xiaohu +5 位作者 LIU Xingliang WANG Jinxi CHENG Song ZHANG Xiuyan LI Dengyu LI Maihe 《Journal of Mountain Science》 SCIE CSCD 2010年第4期327-338,共12页
Little is known about whether soil microbial population dynamics are correlated with forest succession.To test the hypotheses that(1) soil microbial composition changes over successional stages,and(2) soil microbial d... Little is known about whether soil microbial population dynamics are correlated with forest succession.To test the hypotheses that(1) soil microbial composition changes over successional stages,and(2) soil microbial diversity is positively correlated with plant species diversity,we determined the soil microbial populations,community composition,and microflora diversity in evergreen broad-leaved forests along a chronosequence of vegetation succession from 5 to 300 years in southwestern China.The soil microbial community was mainly composed of bacteria(87.1-98.7% of the total microorganisms and 10 genera identified),fungi(0.3-4.0%,7 genera),and actinomycetes(2.1-9.1%,8 species and 1 genus).There were significant differences in soil microbial populations among different successional stages and within the four seasons.The seasonal variations of the soil microbial community may be associated with the seasonal changes in environmental conditions.The changes in soil microbial diversity(Shannon-Wiener index) with successional time followed one-humped,convex curves peaked at-100 years since restoration,which is identical with the trends of the aboveground plant diversity.Higher plant diversity resulting in enhanced nutrient flow and root exudation may contribute to positive relationships between the soil microbial diversity and plant diversity.Hence,decreases in soil microbial diversity in the late-successional stages appear to be related to the net loss in species richness that occurs after 100 years since restoration.Our findings confirm the intermediate disturbance hypothesis that suggests diversity peaks at midsuccessional stages. 展开更多
关键词 ACTINOMYCETES Bacteria Fungi Microbial diversity moist evergreen broad-leavedforest Seasonal dynamics
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Treating aplasia cutis congenita in a newborn with the combination of ionic silver dressing and moist exposed burn ointment: A case report 被引量:4
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作者 Guo-Feng Lei Jun-Ping Zhang +6 位作者 Xiao-Bing Wang Xiao-Li You Jin-Ya Gao Xiao-Mei Li Mei-Ling Chen Xiu-Qin Ning Jiang-Li Sun 《World Journal of Clinical Cases》 SCIE 2019年第17期2611-2616,共6页
BACKGROUND Aplasia cutis congenita (ACC) in newborns is a condition in which congenital defects or hypoplasia is present in part of the epidermis,dermis and even subcutaneous tissue (including muscle and bones).First ... BACKGROUND Aplasia cutis congenita (ACC) in newborns is a condition in which congenital defects or hypoplasia is present in part of the epidermis,dermis and even subcutaneous tissue (including muscle and bones).First reported by Cordon in 1767,ACC is a rare disease with a low incidence of 1/100000 to 3/10000.Currently,there are 500 cases reported worldwide.ACC can be accompanied by other malformations.The onset mechanism of the disease remains unknown but is thought to be correlated to factors such as genetics,narrow uterus,foetal skin and amniotic membrane adhesion,use of teratogenic drugs in early pregnancy and viral infection.CASE SUMMARY In August 2018,we treated a newborn with ACC on the left lower limbs using a combination of ionic silver dressing and moist exposed burn ointment (MEBO) and achieved a satisfactory treatment outcome.The skin defects were observed on the external genitals and on areas from the left foot to 3/4 of the upper left side.Subcutaneous tissue and blood vessels were observed in the regions with skin defects.The following treatments were provided.First,the wound was rinsed with 0.9% sodium chloride solution followed by disinfection with povidone-iodine twice.And then MEBO was applied to the wound at a thickness of approximately 1 mm.After applying ionic silver dressing,the wound was covered with sterile gauze.The wound dressing was replaced every 2-3 d.At the 4-mo follow-up,the treatment outcome was satisfactory.There was minimal scar tissue formation,and limb function was not impaired.CONCLUSION The combination of ionic silver dressing and MEBO to ACC is helpful. 展开更多
关键词 APLASIA cutis congenita Newborns IONIC SILVER DRESSING moist EXPOSED burn OINTMENT
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Structure and regeneration status of Komto Afromontane moist forest, East Wollega Zone, west Ethiopia 被引量:4
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作者 Fekadu Gurmessa Teshome Soromessa Ensermu Kelbessa 《Journal of Forestry Research》 CAS CSCD 2012年第2期205-216,共12页
We conducted a study in Komto Forest in East WoUega Zone, Oromia National Regional State, West Ethiopia for determining vegetation structure and regeneration status in this forest. We systematically sampled 53 quadra... We conducted a study in Komto Forest in East WoUega Zone, Oromia National Regional State, West Ethiopia for determining vegetation structure and regeneration status in this forest. We systematically sampled 53 quadrats (20 m ×20 m) along line transects radiating from the peak of Komto Mountain in eight directions. Vegetation parameters such as DBH, height, seedling and sapling density of woody species, and location and altitude of each quadrat were recorded. In total, 103 woody plant species of 87 genera and 45 families were identified. Analysis of selected tree species revealed different population structures. Generally, the forest was dominated by small trees and shrubs characteristic of secondary regeneration. Observations on the regeneration of the forest indicated that there are woody species that require urgent conservation measures. Based on the results of this study, we recommend detailed ecological studies of various environmental factors such as soil type and properties, and ethnobotanical studies to explore indigenous knowledge on uses of plants. 展开更多
关键词 East Wollega Komto Forest moist montane forest regen- eration status structural analysis
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Tree species diversity and stand structure along major community types in lowland primary and secondary moist deciduous forests in Tripura,Northeast India 被引量:4
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作者 Koushik Majumdar Uma Shankar Badal Kumar Datta 《Journal of Forestry Research》 CAS CSCD 2012年第4期553-568,共16页
Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging ... Tree species diversity and population structure at different community types were described and analyzed for primary and secondary lowland moist deciduous forests in Tripura. Overall 10,957 individual trees belonging to 46 family, 103 genera and 144 species were counted at ≥30 cm DBH (diameter at breast height) using 28 permanent belt transects with a size of 1 ha (10 m × 1000 m). Four different tree communities were identified. The primary forests was dominated by Shorea robusta (mean density 464.77 trees.ha^-1, 105 species) and Schima wallichii (336.25 trees.ha^-1, 82 species), while the secondary forests was dominated by Tectona grandis (333.88 trees.ha^-1, 105 species) and Hevea brasiliensis (299.67 trees.ha^-1, 82 species). Overall mean basal area in this study was 18.01m2.ha^-1; the maximum value was recorded in primary Shorea forest (26.21 m2.ha^-1). Mean density and diversity indices were differed significantly within four different communities. No significant differences were observed in number of species, genera, family and tree basal cover area. Significant relationships were found between the species richness and different tree population groups across the communities. Results revealed that species diversity and density were increased in those forests due to past disturbances which resulted in slow accumu- lation of native oligarchic small tree species. Seventeen species were recorded with 〈2 individuals of which Saraca asoka (Roxb.) de Wilde and Entada phaseoloides (L.) Men'. etc. extensively used in local ethnomedicinal formulations. The present S. robusta Gaertn dominated forest was recorded richer (105 species) than other reported studies. Moraceae was found more speciose family instead of Papilionaceae and Euphorbiaceae than other Indian moist deciduous forests. Seasonal phenological gap in such moist deciduous forests influenced the population of Trachypithecus pileatus and capped langur. The analysis of FIV suggested a slow trend of shifting the population of Lamiaceae group by Moraceae species in secondary T. grandis L. dominated community. 展开更多
关键词 diversity and stand structure moist deciduous forest species conservation tree community types
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A Numerical Study of Mesoscale Vortex Formation in the Midlatitudes:The Role of Moist Processes 被引量:5
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作者 Yongqiang JIANG Yuan WANG +2 位作者 Chaohui CHEN Hongrang HE Hong HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第1期65-78,共14页
In this study, a three-dimensional mesoscale model was used to numerically simulate the well-known "98.7" heavy rainfall event that affected the Yangtze Valley in July 1998. Two experiments were conducted to... In this study, a three-dimensional mesoscale model was used to numerically simulate the well-known "98.7" heavy rainfall event that affected the Yangtze Valley in July 1998. Two experiments were conducted to analyze the impact of moist processes on the development of meso-β scale vortices(MβV) and their triggering by mesoscale wind perturbation(MWP). In the experiment in which the latent heat feedback(LHF) scheme was switched off, a stable low-level col field(i.e., saddle field—a region between two lows and two highs in the isobaric surface) formed, and the MWP triggered a weak MβV. However, when the LHF scheme was switched on as the MWP was introduced into the model, the MβV developed quickly and intense rainfall and a mesoscale low-level jet(mLLJ) were generated. The thickness of the air column and average temperature between 400 and 700 hPa decreased without the feedback of latent heat, whereas they increased quickly when the LHF scheme was switched on, with the air pressure falling at low levels but rising at upper levels. A schematic representation of the positive feedbacks among the mesoscale vortex, rainfall, and mLLJ shows that in the initial stage of the MβV, the MWP triggers light rainfall and the latent heat occurs at low levels, which leads to weak convergence and ageostrophic winds. In the mature stage of the MβV, convection extends to the middle-to-upper levels, resulting in an increase in the average temperature and a stretching of the air column. A low-level cyclonic circulation forms under the effect of Coriolis torque, and the m LLJ forms to the southeast of the MβV. 展开更多
关键词 moist process latent heat feedback mesoscale vortex col field
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Sensitivity of Cyclone Tracks to the Initial Moisture Distribution:A Moist Potential Vorticity Perspective 被引量:3
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作者 Zuohao CAO Da-Lin ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第6期807-820,共14页
In this study, the characteristics of moist potential vorticity (MPV) in the vicinity of a surface cyclone center and their physical processes axe investigated. A prognostic equation of surface absolute vorticity is... In this study, the characteristics of moist potential vorticity (MPV) in the vicinity of a surface cyclone center and their physical processes axe investigated. A prognostic equation of surface absolute vorticity is then used to examine the relationship between the cyclone tracks and negative MPV (NMPV) using numerical simulations of the life cycle of an extratropical cyclone. It is shown that the MPV approach developed herein, i.e., by tracing the peak NMPV, can be used to help trace surface cyclones during their development and mature stages. Sensitivity experiments are conducted to investigate the impact of different initial moisture fields on the effectiveness of the MPV approach. It is found that the lifetime of NMPV depends mainly on the initial moisture field, the magnitude of condensational heating, and the advection of NMPV. When NMPV moves into a saturated environment at or near a cyclone center, it can trace better the evolution of the surface cyclone due to the conservative property of MPV. It is also shown that the NMPV generation is closely associated with the coupling of large potential temperature and moisture gradients as a result of frontogenesis processes. Analyses indicate that condensation, confluence and tilting play important but different roles in determining the NMPV generation. NMPV is generated mainly through the changes in the strength of baroclinicity and in the direction of the moisture gradient due to moist and/or dry air mass intrusion into the baroclinic zone. 展开更多
关键词 cyclone tracks moist potential vorticity mid-latitude cyclones
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Effect of moisture and fungal exposure on the mechanical properties of hem-fir plywood 被引量:2
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作者 WANG Wei-hong Scott Kent +2 位作者 Camille Freitag Rorbert J. leichti Jeffrey J. Morrell 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期299-300,共2页
Hem-fir plywood were exposed to two brown rot fungi, Gloeophyllum trabeum and Postia placenta, and one white rot fungus, Trametes versicolor, to investigate the effect of fungal decay on mechanical properties of plywo... Hem-fir plywood were exposed to two brown rot fungi, Gloeophyllum trabeum and Postia placenta, and one white rot fungus, Trametes versicolor, to investigate the effect of fungal decay on mechanical properties of plywood. Results showed that modulus of rupture (MOR) and modulus of elasticity (MOE) of hem-fir plywood declined significantly by inoculating fungi, and weight loss of sample had a modest decrease. The fungi also made a greater effect on MOR than on MOE. Of three fungi, Postia placenta caused a most significant weight loss, and Gloeophyllum trabeum resulted in a largest flexural properties loss. Substantial declines in MOR and MOE of hem-fir plywood were also observed when the plywood samples were stored under wet conditions over 15 weeks, even in the absence of fungal attack. 展开更多
关键词 Fungus decay Weight loss Flexural properties moist condition PLYWOOD MOR MOE
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The Impact of Moist Physics on the Sensitive Area Identification for Heavy Rainfall Associated Weather Systems 被引量:3
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作者 Huizhen YU Zhiyong MENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第5期684-696,共13页
The impact of moist physics on the sensitive areas identified by conditional nonlinear optimal perturbation(CNOP)is examined based on four typical heavy rainfall cases in northern China through performing numerical ex... The impact of moist physics on the sensitive areas identified by conditional nonlinear optimal perturbation(CNOP)is examined based on four typical heavy rainfall cases in northern China through performing numerical experiments with and without moist physics.Results show that the CNOP with moist physics identifies sensitive areas corresponding to both the lower-(850−700 hPa)and upper-level(300−100 hPa)weather systems,while the CNOP without moist physics fails to capture the sensitive areas at lower levels.The reasons for the CNOP peaking at different levels can be explained in both algorithm and physics aspects.Firstly,the gradient of the cost function with respect to initial perturbations peaks at the upper level without moist physics which results in the upper-level peak of the CNOP,while it peaks at both the upper and lower levels with moist physics which results in both the upper-and lower-level peaks of the CNOP.Secondly,the upper-level sensitive area is associated with high baroclinicity,and these dynamic features can be captured by both CNOPs with and without moist physics.The lower-level sensitive area is associated with moist processes,and this thermodynamic feature can be captured only by the CNOP with moist physics.This result demonstrates the important contribution of the initial error of lower-level systems that are related to water vapor transportation to the forecast error of heavy rainfall associated weather systems,which could be an important reference for heavy rainfall observation targeting. 展开更多
关键词 moist physics heavy rainfall sensitive area CNOP
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A Modified Moist Ageostrophic Q Vector 被引量:2
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作者 岳彩军 寿绍文 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1053-1061,共9页
The quasi-geostrophic Q vector is an important rainfall associated with large-scale weather systems diagnostic tool for studying development of surface and is calculated using data at single vertical level. When ageos... The quasi-geostrophic Q vector is an important rainfall associated with large-scale weather systems diagnostic tool for studying development of surface and is calculated using data at single vertical level. When ageostrophic Q vector was introduced, it required data at two vertical levels. In this study, moist ageostrophic Q vector is modified so that it can be calculated using data at a single vertical level. The comparison study between the original and modified moist ageostrophic Q vectors is conducted using the data from 5 to 6 July 1991 during the torrential rainfall event associated with the Changjiang-Huaihe mei-yu front in China. The results reveal that divergences of original and modified moist ageostrophic Q vectors have similar horizontal distributions and their centers are almost located in the precipitation centers. This indicates that modified moist ageostrophic Q vector can be used to diagnose convective development with reasonable accuracy. 展开更多
关键词 moist ageostrophic Q vector MODIFICATION latent heating torrential rainfall associated with mei-yu front
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Application and Characteristic Analysis of the Moist Singular Vector in GRAPES-GEPS 被引量:3
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作者 Jing WANG Bin WANG +3 位作者 Juanjuan LIU Yongzhu LIU Jing CHEN Zhenhua HUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第11期1164-1178,共15页
The singular vector(SV)initial perturbation method can capture the fastest-growing initial perturbation in a tangent linear model(TLM).Based on the global tangent linear and adjoint model of GRAPES-GEPS(Global/Regiona... The singular vector(SV)initial perturbation method can capture the fastest-growing initial perturbation in a tangent linear model(TLM).Based on the global tangent linear and adjoint model of GRAPES-GEPS(Global/Regional Assimilation and Prediction System-Global Ensemble Prediction System),some experiments were carried out to analyze the structure of the moist SVs from the perspectives of the energy norm,energy spectrum,and vertical structure.The conclusions are as follows:The evolution of the SVs is synchronous with that of the atmospheric circulation,which is flowdependent.The moist and dry SVs are located in unstable regions at mid-to-high latitudes,but the moist SVs are wider,can contain more small-and medium-scale information,and have more energy than the dry SVs.From the energy spectrum analysis,the energy growth caused by the moist SVs is reflected in the relatively small-scale weather system.In addition,moist SVs can generate perturbations associated with large-scale condensation and precipitation,which is not true for dry SVs.For the ensemble forecasts,the average anomaly correlation coefficient of large-scale circulation is better for the forecast based on moist SVs in the Northern Hemisphere,and the low-level variables forecasted by the moist SVs are also improved,especially in the first 72 h.In addition,the moist SVs respond better to short-term precipitation according to statistical precipitation scores based on 10 cases.The inclusion of the large-scale condensation process in the calculation of SVs can improve the short-term weather prediction effectively. 展开更多
关键词 moist singular vector GRAPES-GEPS adjoint model ensemble prediction
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