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A Systems Approach for Analyzing Vegetative and Soil Degradation in Arnigad Micro-watershed of Indian Himalayan Region

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Journal of Mountain Science 2010年第4期7卷 315-326页

作者： Mohit Gera prem l.sankhayan Ole Hofstad Govt. of J&K VanbhavanBelow GumatJammu-180001(J&K) India Department of Ecology and Natural Resource Management Norwegian University of Life Sciences(UMB)P.O.Box 5003N-1432 sNorway

This study analyzes the vegetative and soil degradation,measured as biomass and soil loss,for Arnigad micro-watershed located in Indian Himalayan state of Uttarakhand,in systems framework by using dynamic linear programming bio-economic *** focus is at investigating the effects of alternate policy regimes,i.e.,introduction of improved energy sources for cooking along with substitution of existing local livestock breeds with improved breed,reduction in human population growth and introduction of high yielding varieties of main crops including paddy,maize and *** model horizon extended over a period of 25 years,i.e.,from 2006 to *** was found that the model scenario incorporating increased use of improved energy sources along with substitution of local cows by improved cows could be the most effective policy option in reducing vegetative and soil *** vegetative biomass density declined to 19.76% compared to 35.24% in the BASE scenario and soil erosion loss was also lowered by 29.13%.Also,the reduction of population growth rate to half of the BASE scenario led to minor improvements in *** of high yielding varieties of main crops slightly increased vegetative degradation but reduced soil loss(8.35%) with respect to the BASE *** a phenomenon could be explained in terms of changed crop mix resulting in reduced amount of crop by-products requiring increased lopping of tree branches for animal *** policy option of the increased use of improved energy sources along with substitution of improved breed of cows resulted in 9.58% higher *** of high yielding varieties of crops led to 1.92% increase in income,but the income decreased by 1.25 % when population growth was reduced to *** usefulness of the model lies in analyzing the systems behavior in its entirety where the results can predict the possible direction of change as a result of manipulation in alternate economic regimes.

关键词： Bio-economic model Dynamic linearprogramming Improved energy sources Vegetativeand soil degradation Soil erosion Indian Himalayanregion

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Estimating the Yield loss of Winter Wheat from Drought in the United States Southern Plains Region as Influenced by El Niño-Southern Oscillation (ENSO)

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Agricultural Sciences 2024年第9期15卷 1018-1034页

作者： prem Woli Gerald R. Smith Charles R. long Francis M. Rouquette, Jr. Texas A&M Agrilife Research Center Overton USA

Wheat (Triticum aestivum l.) production is a major economic activity in most regional and rural areas in the Southern Plains, a semi-arid region of the United States. This region is vulnerable to drought and is projected to experience a drier climate in the future. Since the interannual variability in climate in this region is linked to an ocean-atmospheric phenomenon, called El Niño-Southern Oscillation (ENSO), droughts in this region may be associated with ENSO. Droughts that occur during the critical growth phases of wheat can be extremely costly. However, the losses due to an impending drought can be minimized through mitigation measures if it is predicted in advance. Predicting the yield loss from an imminent drought is crucial for stakeholders. One of the reliable ways for such prediction is using a plant physiology-based agricultural drought index, such as Agricultural Reference Index for Drought (ARID). This study developed ENSO phase-specific, ARID-based models for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to drought. The reasonable values of the drought sensitivity coefficients of the yield model for each ENSO phase (El Niño, la Niña, or Neutral) indicated that the yield models reflected reasonably well the phenomena of water stress decreasing the winter wheat yields in this region during different ENSO phases. The values of various goodness-of-fit measures used, including the Nash-Sutcliffe Index (0.54 to 0.67), the Willmott Index (0.82 to 0.89), and the percentage error (20 to 26), indicated that the yield models performed fairly well at predicting the ENSO phase-specific loss of wheat yields from drought. This yield model may be useful for predicting yield loss from drought and scheduling irrigation allocation based on the phenological phase-specific sensitivity to drought as impacted by ENSO.

关键词： ARID Drought Drought Index ENSO El Niño Growth-Stage Model Phenological-Phase Prediction Semi-Arid Wheat Yield loss

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Estimating the Drought-Induced Yield loss for Winter Wheat in a Semi-Arid Region of the Southern United States Using a Drought Index

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Agricultural Sciences 2024年第8期15卷 812-829页

作者： prem Woli Qingwu Xue Gerald R. Smith Charles R. long Francis M. Rouquette Jr. Texas A&M Agrilife Research Center Overton Texas USA Texas A&M Agrilife Research Center Amarillo Texas USA

The economy of most rural locations in the semi-arid region of llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum l.) production. This region is prone to drought and is projected to experience a drier climate. Droughts that coincide with the critical phenological phases of a crop can be remarkably costly. Although drought cannot be prevented, its losses can be minimized through mitigation measures if it is predicted in advance. Predicting yield loss from an imminent drought is an important need of stakeholders. One way to fulfill this need is using an agricultural drought index, such as the Agricultural Reference Index for Drought (ARID). Being plant physiology-based, ARID can represent drought-yield relationships accurately. This study developed an ARID-based yield model for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to water stress. The reasonable values of the drought sensitivity coefficients of the yield model indicated that it could reflect the phenomenon of water stress decreasing the winter wheat yields in this region reasonably. The values of the various metrics used to evaluate the model, including Willmott Index (0.86), Nash-Sutcliffe Index (0.61), and percentage error (26), indicated that the yield model performed fairly well at predicting the drought-induced yield loss for winter wheat. The yield model may be useful for predicting the drought-induced yield loss for winter wheat in the study region and scheduling irrigation allocation based on phenological phase-specific drought sensitivity.

关键词： ARID Drought Drought index Growth-stage Model Phenological-Phase Prediction Semi-Arid Wheat Yield

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Unique and conserved features of floral evocation in legumes

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Journal of Integrative Plant Biology 2014年第8期56卷 714-728页

作者： lim Chee liew Mohan B. Singh prem l. Bhalla Plant Molecular Biology and Biotechnology laboratory Melbourne School of Land and Environment University of Melbourne

legumes, with their unique ability to fix atmo- spheric nitrogen, play a vital role in ensuring future food security and mitigating the effects of climate change because they use less fossil energy and produce less greenhouse gases compared with N-fertilized systems. Grain legumes are second only to cereal crops as a source of human and animal food, and they contribute approximately one third of the protein consumed by the human population. The productivityof seed crops, such as grain legumes, is dependent on flowering. Despite the genetic variation and importance of flowering in legume production, studies of the molecular pathways that control flowering in legumes are limited. Recent advances in genomics have revealed that legume flowering pathways are divergent from those of such model species as Arabidopsis thaliana. Here, we discuss the current understanding of flowering time regulation in legumes and highlight the unique and conserved features of floral evocation in legumes.

关键词： Flowering legume soybean

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Distribution,Use Pattern and Prospects for Conservation of Medicinal Shrubs in Uttaranchal State,India

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Journal of Mountain Science 2007年第2期4卷 155-180页

作者： Bhupendra S. Adhikari Mani M. Babu prem l. Saklani Gopal S. Rawat Herbarium Section Department of Habitat Ecology Wildlife Institute of India P.O. Box # 18 Chandrabani Dehra Dun 248 001 Uttaranchal

The present paper gives an insight into the distribution and use pattern of medicinal shrubs in Uttaranchal State. A total of 222 medicinal and aromatic shrub species have been appended based on secondary information. Euphorbiaceae, Rosaceae, Verbenaceae, and Fabaceae have the highest repre- sentatives of medicinal shrubs. Twenty one families had one species each in medicinal use. Verbenaceae and Euphorbiaceae in the sub-tropical region, Rosaceae in the temperate region, and Ericaceae and Rosaceae in the sub-alpine and alpine regions, respectively, had the highest representatives of medicinal shrubs. The distribution of medicinal shrubs was 42 % in sub-tropical, 29 % in warm temperate, 13 % in cool temperate, 9 % in sub-alpine and 7 % in the alpine region. Of the total species, 70 medicinal shrubs were native to the Himalayas and 22 native to Himalayan region including other Hima- layan countries. The most frequently used plant parts for various ailments were leaves (31 %) and roots (23 %). Most shrubs are being used for the diseases, viz. skin diseases, dysentery, cough, fever, wounds, and rheumatism. The present paper will help in the execution of strategies for promotion and cultivation of medicinal shrubs in Uttaranchal State.

关键词： Medicinal shrub distribution use pattern eco-region Uttaranchal Himalayan region India

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Biological Parts for Engineering Abiotic Stress Tolerance in Plants

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BioDesign Research 2022年第1期2022卷 395-435页

作者： Neeta lohani Mohan B.Singh prem l.Bhalla Plant Molecular Biology and Biotechnology laboratory Faculty of Veterinary and Agricultural SciencesThe University of MelbourneParkvilleVIC 3010Australia

It is vital to ramp up crop production dramatically by 2050 due to the increasing global population and demand for ***, with the climate change projections showing that droughts and heatwaves becoming common in much of the globe,there is a severe threat of a sharp decline in crop yields. Thus, developing crop varieties with inbuilt genetic tolerance toenvironmental stresses is urgently needed. Selective breeding based on genetic diversity is not keeping up with the growingdemand for food and feed. However, the emergence of contemporary plant genetic engineering, genome-editing, and syntheticbiology offer precise tools for developing crops that can sustain productivity under stress conditions. Here, we summarize thesystems biology-level understanding of regulatory pathways involved in perception, signalling, and protective processesactivated in response to unfavourable environmental conditions. The potential role of noncoding RNAs in the regulation ofabiotic stress responses has also been highlighted. Further, examples of imparting abiotic stress tolerance by geneticengineering are discussed. Additionally, we provide perspectives on the rational design of abiotic stress tolerance throughsynthetic biology and list various bioparts that can be used to design synthetic gene circuits whose stress-protective functionscan be switched on/off in response to environmental cues.

关键词： protective crops precise

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Four-Way Turiyam Set-Based Human Quantum Cognition Analysis

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Journal of Artificial Intelligence and Technology 2022年第4期2卷 144-151页

作者： prem Kumar Singh Department of Computer Science and Engineering Gandhi Institute of Technology and Management-VisakhapatnamAndhra Pradesh 530045India

Recently, the Turiyam set was introduced for characterization of data sets beyond true, false, and uncertain regionsbased on human cognition. This set is able to represent the unknown, undefined, or conduit metaphor of human quantumcognition precisely. One of the suitable examples is USA–Russia conflicts or Cold war is beyond the characterization of win,draw, or loss. It is totally based on the conduit metaphor of USA and Russia. In this case, a set of countries that may supportRussia (Sr) can be characterized as true regions. A set of countries that does not support Russia (i.e., supporting the USA) can becharacterized as false regions (Su). There is also a set of countries that supports both Russia–USA based on the given *** types of countries and their vote are uncertain. The fourth case is some countries like India, China, and UAE that choosenothing to fulfill their conduit metaphor. It is called Turiyam or four-dimension cognition. The characterization of this typeof four-dimension Turiyam cognition and its representation is one of the crucial tasks for data science researchers. It is indeed arequirement to understand the human quantum cognition and its conduit metaphor. To tackle this issue, the current paper will tryto introduce a method for characterization of this undefined, unknown, or Turiyam cognition via a defined interval set. Theobjective is to provide a way to explore them in known graph (t), not known graph (f), partial graph (i), or unknown graph (l) withan example.

关键词： fourth dimensions knowledge representation non-Euclidean Quaternion Turiyam set unknown

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A 2000 Year Multi-Proxy Evidence of Natural/Anthropogenic Influence on Climate from the Southwest Coast of India

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Journal of Earth Science 2020年第5期31卷 1029-1044页

作者： M.C.Manoj Jyoti Srivastava prem Raj Uddandam Biswajeet Thakur Birbal Sahni Institute of Paleosciences 53 University RoadL ucknowUttar Pradesh 226007India Banaras Hindu University VaranasiUttar PradeshIndia

The last millennium climate reconstructions are complex and limit our understanding of the mechanisms behind environmental and climate variability. We present multi-proxy centennial-scale records from the Cherai, southwest India. The last 2000 cal yr AD record suggests a complex environmental condition that prevailed at the depositional site augmenting the role of natural as well as anthropogenic agents. Increased elemental variations and indices values indicate stronger weathering, presumably wetter conditions and intense precipitation. Provenance studies suggest diverse sources and the main composition fall close to the Charnockite and Gneissic composition. Multi-proxy data suggests that a shift towards wetter climatic conditions, which occurred from 910 to 1230 cal yr AD. The core also records a shift towards the drier conditions that started around 1230 cal yr AD with a loss in vegetation diversity. The pollution load index values suggest that the overall study area falls in moderate contamination levels, which are also substantiated with the diatom data indicating human influence in the natural habitat during the deposition time. The present study reveals that the enhanced Cd and As concentration is due to strong anthropogenic influence. We compared the multi-proxy record with other continental and marine palaeoclimatic records to explore global and/or regional trends in climate variability during the last 2000 years.

关键词： estuaries monsoon provenance vegetation clmate contamination

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MUlTIDENTATE lIGAND EXCHANGE KINETICS: REACTIONS OF AMINOCARBOXYlATO-FERRATE(Ⅲ) COMPlEXES WITH 4-(2-PYRIDYlAZO) RESORCINOl

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无机化学学报 1989年第3期 61-72页

作者： NISHI GUPTA,prem C.NIGAM Department of Chemistry Indian Institute of Technology India Department of Chemistry Indian Institute of Technology India

The kinetics and mechanism of ligand substitution reactions of nitrilotriacetatoiron（Ⅲ）, [Fe（NTA）], and N-（2-hydroxyethyl）-ethylenediaminetfiacetatoiron（Ⅲ）, [Fe（HEDTA）], complexes with 4-（2-pyridylazo） resorcinol （Par） has been investigated at pH = 9.0±0.02, I= 0.1mol·1-1（NaClO4）, and temp. = 25 ±0.1℃ and 30±0.1℃ respectively. The reaction has been studied spectrophotometrically at 496 nm. (λmaxof Fe（Par）2). In both reactions the final product was [Fe（Par）2]-. The values of second order rate constants for NTA and HEDTA exchange reactions are （10.0±0.8）×10～1·mol-1·s-1and （2.7± 0.1）×10-11·mol-1·s-1respectively. The reactions of NTA and HEDTA exchange were studied in the pH range 6-9.5 and 7-10.85 respectively. The rate of reacton of [Fe（NTA）] with HPar-first increases with pH and then levels off. However, in the case of [Fe（HEDTA）] reaction, the rate increases monotonically with increase of pH in the specified range. The reverse reactions between [Fe（Par）2

关键词： kinetic multidentate exchange aminocarboxylatoferrate(Ⅲ) Par

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Tuning the particle size and morphology of high energetic material nanocrystals

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Defence Technology（防务技术） 2015年第4期11卷 382-389页

作者： Raj KUMAR prem Felix SIRIl Pramod SONI School of Basic Sciences and Advanced Materials Research Centre Indian Institute of Technology Mandi Terminal Ballistics Research laboratory

Morphology controlled synthesis of nanoparticles of powerful high energetic compounds(HECs) such as l,3,5-trinitro-l,3,5-triazinane(RDX) and 1,3,5,7-tetranitro-l,3,5,7-tetrazocane(HMX) were achieved by a simple solvent—antisolvent interaction(SAI) method at 70 ℃.The effects of different solvents on particle size and morphology of the prepared nano-HECs were studied *** size and morphology of the nano-HECs was characterized using field emission scanning electron microscopy(FE-SEM) imaging.X-ray diffraction(XRD) and Fourier transform infrared(FTIR) spectroscopy studies revealed that RDX and HMX were precipitated in their most stable polymorphic forms,i.e.a and P,*** analysis coupled with differential scanning calorimetry(TGA-DSC) studies showed that the thermal response of the nanoparticles was similar to the respective *** nanoparticles with spherical and rod shaped morphology were observed under different solvent *** mean particle size also varied considerably with the use of different solvents.

关键词：平均粒径高含能材料形貌纳米晶体场发射扫描电子显微镜差示扫描量热法纳米颗粒纳米粒子

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