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Assessment of biomass and net primary productivity of a dry tropical forest using geospatial technology

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Journal of Forestry research 2019年第1期30卷 157-170页

作者： Tarun Kumar Thakur S.L.Swamy Arvind Bijalwan Mammohan J.r.Dobriyal Department of Environmental Science Indira Gandhi National Tribal University (IGNTU) Department of Forestry Indira Gandhi Agricultural University Faculty of Technical Forestry Indian Institute of Forest Management Navsari Agriculture University

This study quantifies biomass, aboveground and belowground net productivity, along with additional environmental factors over a 2-3 year period in Barnawapara Sanctuary of Chhattisgarh, India through satellite remotesensing and GIS techniques. Ten sampling quadrates20×20, 5×5 and 1×1 m were randomly laid for overstorey (OS), understorey (US) and ground vegetation(GS), respectively. Girth of trees was measured at breast height and collar diameters of shrubs and herbs at 0.1 m height. Biomass was estimated using allometric regression equations and herb biomass by harvesting. Net primary productivity (NPP) was determined by Ssumming biomass increment and litter crop values. Aspect and slope influenced the vegetation types, biomass and NPP in different forests. Standing biomass and NPP varied from 18.6 to101.5 Mg ha^(-1) and 5.3 to 12.7 Mg ha^(-1) a^(-1), respectively,in different forest types. The highest biomass was found in dense mixed forest, while net production recoded in Teak forests. Both were lowest in degraded mixed forests of different forest types. OS, US and GS contributed 90.4, 8.7and 0.7%, respectively, for the total mean standing biomass in different forests. This study developed spectral models for the estimation of biomass and NPP using Normalized Difference Vegetation Index and other vegetation *** study demonstrated the potential of geospatial tools for estimation of biomass and net productivity of dry tropical forest ecosystem.

关键词： Allometric regression equations Fine root biomass Litter fall LAI NDVI Spectral models

Clustering Gene Expression Data Through Modified Agglomerative M-CUrE Hierarchical Algorithm

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Computer Systems Science & Engineering 2022年第6期41卷 1027-1041页

作者： E.Kavitha r.Tamilarasan N.Poonguzhali M.K.Jayanthi Kannan A Constituent College of Anna University University College of EngineeringVillupuram605103India A Constituent College of Anna University University College of EngineeringPattukkottai614701India Department of Computer Science and Engineering Manakula Vinayagar Institute of TechnologyPuducherry605107India Department of Computer Science Engineering Faculty of Engineering and TechnologyJAIN(Deemed-To-Be University)Bangalore562112India

Gene expression refers to the process in which the gene information isused in the functional gene product synthesis. They basically encode the proteinswhich in turn dictate the functionality of the cell. The first step in gene expressionstudy involves the clustering usage. This is due to the reason that biological networks are very complex and the genes volume increases the comprehending challenges along with the data interpretation which itself inhibit vagueness, noise andimprecision. For a biological system to function, the essential cellular moleculesmust interact with its surrounding including rNA, DNA, metabolites and proteins. Clustering methods will help to expose the structures and the patterns inthe original data for taking further decisions. The traditional clustering techniquesinvolve hierarchical, model based, partitioning, density based, grid based and softclustering methods. Though many of these methods provide a reliable output inclustering, they fail to incorporate huge data of gene expressions. Also, thereare statistical issues along with choosing the right method and the choice of dissimilarity matrix when dealing with gene expression data. We propose to use amodified clustering algorithm using representatives (M-CUrE) in this workwhich is more robust to outliers as compared to K-means clustering and also ableto find clusters with size variances.

关键词： Clustering gene identifiers representatives dimension reduction

Irrigation Water Use Efficiency of Farmers and Its Determinants: Evidence from a Survey in Northwestern China

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Agricultural Sciences in China 2010年第9期9卷 1326-1337页

作者： WANG Xue-yuan College of Economics, Zhejiang Gongshang University, Hangzhou 310018, P.r.China College of Economics Zhejiang Gongshang University Hangzhou 310018 P.R. China

Irrigation water shortage is becoming an increasingly serious problem in agricultural production. In this case, it is very important for policy makers to take measures to improve irrigation water use efficiency, especially in the water-scarce areas. In this paper, the data envelopment analysis （DEA） techniques, based on the concept of input-specific technical efficiency were used to develop farm-level technical efficiency measures and sub-vector efficiencies for irrigation water use. The Tobit regression technique was then adopted to identify the factors that influence irrigation water efficiency differentials under the shortage of water resources. Based on a sample data of 432 wheat farmers in northwestern China, our experimental results of the DEA analysis showed the average technical efficiency of 0.6151. It suggested that wheat farmers could increase their production by as much as 38.49% by using inputs more efficiently. Further, the mean irrigation water efficiency of 0.3065, suggested that wheat farmers could produce the same quantity of wheat using the same quantity of inputs but with 69.35% less water. The results of the Tobit regression analysis showed that the farmer＇s age, income, education level, and the farm size tended to affect the degree of irrigation water efficiency positively, and the channel conditions and different irrigation methods made a significant impact on irrigation water use efficiency. Furthermore, the arrangements of exclusive water property rights and competitive water price mechanism have effectively encouraged the water saving behavior of farmers. These results are valuable for policy makers since it could help to guide policies towards high irrigation water use efficiency.

关键词： irrigation water efficiency determinants data envelopment analysis Tobit regression

Prevention of laryngeal webs through endoscopic keel placement for bilateral vocal cord lesions

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Frontiers of Medicine 2018年第3期12卷 301-306页

作者： Jian Chen Yilai Shu Matthew r. Naunheim Min Chen Lei Cheng Haitao Wu Department of Otolaryngology-Head and Neck Surgery Eye Ear Nose and Throat Hospital Fudan University Shanghai Key Clinical Disciplines of Otorhinolaryngology Shanghai 200031 China Department of Otology and Laryngology Harvard Medical School Boston MA 02138 USA Department of Otolaryngology Massachusetts Eye and Ear Infirmary Boston MA 02138 USA

Transoral microresection for treatment of vocal cord lesions involving the anterior commissure may result in anterior glottic webs. In this study, we retrospectively reviewed 54 patients who underwent microsurgery for bilateral lesions involving the anterior commissure and categorized them into two groups. The keel placement and control groups received endoscopic keel placement and mitomycin C, respectively. During the follow-up of at least 1 year, the laryngeal web formation rate significantly decreased in the keel placement group compared with that in the control group （18.6% versus 54.5%, P 〈 0.05）. Furthermore, the voice handicap index-10 scores for patients without web formation decreased in both the keel placement and control groups （P 〈 0.0001 and P 〈 0.001, respectively）. A pseudomembrane covering the vocal cords was detected in 16.3% （7 of 43） cases after keel removal. A total of 100% （7 of 7） of these cases and 2.8% （1 of 36） of the other cases formed laryngeal webs （P 〈 0.0001）. Endoscopic keel placement could be an effective method for preventing anterior glottic webs after surgery for bilateral vocal cord diseases involving the anterior commissure. The pseudomembrane observed at the time of keel removal may imply a high risk of web formation.

关键词： glottic stenosis glottic web laryngeal keel silastic sheets anterior commissure

recent advances and applications of machine learning in solidstate materials science

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npj Computational Materials 2019年第1期5卷 394-429页

作者： Jonathan Schmidt Mário r.G.Marques Silvana Botti Miguel A.L.Marques Institut für Physik Martin-Luther-Universität06120 Halle-WittenbergHalle(Saale)Germany Institut für Festkörpertheorie und-optik Friedrich-Schiller-Universität JenaMax-Wien-Platz 107743 JenaGermany

One of the most exciting tools that have entered the material science toolbox in recent years is machine *** collection of statistical methods has already proved to be capable of considerably speeding up both fundamental and applied *** present,we are witnessing an explosion of works that develop and apply machine learning to solid-state *** provide a comprehensive overview and analysis of the most recent research in this *** a starting point,we introduce machine learning principles,algorithms,descriptors,and databases in materials *** continue with the description of different machine learning approaches for the discovery of stable materials and the prediction of their crystal *** we discuss research in numerous quantitative structure–property relationships and various approaches for the replacement of first-principle methods by machine *** review how active learning and surrogate-based optimization can be applied to improve the rational design process and related examples of *** major questions are always the interpretability of and the physical understanding gained from machine learning *** consider therefore the different facets of interpretability and their importance in materials ***,we propose solutions and future research paths for various challenges in computational materials science.

关键词： learning gained starting

roles of Superthermal Electrons and Adiabatic Heavy Ions on Heavy-Ion-Acoustic Solitary and Shock Waves in a Multi-Component Plasma

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Communications in Theoretical Physics 2015年第8期64卷 208-214页

作者： M.G.Shah M.M.rahman M.r.Hossen A.A.Mamun Department of Physics Jahangirnagar University Department of Natural Sciences Daffodil International University

Heavy-ion-acoustic(HIA) waves in an unmagnetized collisionless plasma system comprising superthermal electrons, Boltzmann distributed light ions, and adiabatic positively charged inertial heavy ions have been investigated both numerically and analytically. The well-known reductive perturbation method has been used to derive the Kortewegde Vries(K-d V) and Burgers(BG) equations. The parametric regimes for the existence of both the positive and negative solitary and shock waves have been obtained. The effects of adiabaticity of heavy ions and superthermality of electrons,which are found to notably modify the fundamental features(viz. polarity, amplitude, phase speed, etc.) of HIA solitary and shock waves, are precisely studied. The results of our theoretical investigation can be applicable to understand the characteristics and basic nonlinear structures of HIA waves both in space and laboratory plasma situations.

关键词： heavy-ion acoustic waves superthermality adiabatic

Saccharification of Sugarcane Bagasse Using an Enzymatic Extract Produced by Aspergillus fumigatus

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Journal of renewable Materials 2018年第2期6卷 169-175页

作者： Kenia F.r.Lamounier Patrisia O.rodrigues Daniel Pasquini Milla A.Baffi Institute of Agricultural Sciences Federal University of Uberlândia(UFU)UberlândiaMG38408-100Brazil Chemistry Institute Federal University of Uberlândia(UFU)UberlândiaMG38408-100Brazil

This study investigates the efficiency of a crude enzymatic extract produced by Aspergillus fumigatus SCBM6 by solid state fermentation(SSF)in the hydrolysis of alkali pretreated sugarcane bagasse(PTB).After SSF using in natura sugarcane bagasse(SCB),the enzymatic extract presented 21.33 U.g^-1 of β-glucosidase and 544.46 U.g^-1 of *** alkaline pretreatment with sodium hydroxide 2%NaOH(w/v)removed 43% of the lignin from PTB and the cellulosic fraction increased to 75%.The hydrolysis was optimized as a function of time,temperature,and concentration of *** hydrolysis,the maximum yield(30.05%)of total released reducing sugars(TrS)was obtained under the following conditions:24 h,55℃,2% of PTB and 3 U.g^-1 of β-glucosidase(CBU).Furthermore,an approximate TrS value(26.4%)was also obtained after saccharification carried out during 6 h,55℃,4% of PTB and 1 *** results indicate that hydrolysis can be performed in a short incubation period and with low enzymatic load for reasonable TrS release.

关键词： A.fumigatus enzymatic hydrolysis sugarcane bagasse alkaline pretreatment solid state fermentation

Campaign-style U-Pb titanite petrochronology:Along-strike variations in timing of metamorphism in the Himalayan metamorphic core

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Geoscience Frontiers 2019年第3期10卷 827-847页

作者： Catherine M.Mottram John M.Cottle Andrew r.C.Kylander-Clark School of Earth and Environmental Sciences University of Portsmouth Department of Earth Science University of CaliforniaSanta Barbara

Present-day along-strike heterogeneities within the Himalayan orogen are seen at many scales, from variations within the deep architecture of the lithospheric mantle, to differences in geomorphologic surface processes. Here, we present an internally consistent petrochronologic dataset from the Himalayan metamorphic core(HMC), in order to document and investigate the causes of along-strike variations in its Oligocene-Miocene tectonic history. Laser ablation split-stream analysis was used to date and characterise the geochemistry of titanite from 47 calc-silicate rocks across >2000 km along the *** combined U-Pb-rEE-Zr single mineral dataset circumvents uncertainties associated with interpretations based on data compilations from different studies, mineral systems and laboratories, and allows for direct along-strike comparisons in the timing of metamorphic processes. Titanite dates range from ～30 Ma to 12 Ma, recording(re-)crystallization between 625 ℃ and 815 ℃. Titanite T-t data overlap with previously published P-T-t paths from interleaved peltic rocks, demonstrating the usefulness of titanite petrochronology for recording the metamorphic history in lithologies not traditionally used for thermobarometry. Overall, the data indicate a broad eastward-younging trend along the *** in the duration and timing of metamorphism within the HMC are best explained by alongstrike variations in the position of ramps on the basal detachment controlling a two-stage process of preferential ductile accretion at depth followed by the formation of later upper-crust brittle *** processes, coupled with variable erosion, resulted in the asymmetric exhumation of a younger,thicker crystalline core in the eastern Himalaya.

关键词： Himalaya Petrochronology Titanite Metamorphic petrology

Foucault, Douglass, Fanon, and Scotus in dialogue

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Foucault, Douglass, Fanon, and Scotus in dialogue