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Biomass production and carbon balance in two hybrid poplar(Populus euramericana)plantations raised with and without agriculture in southern France

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Journal of Forestry Research 2018年第6期29卷 1689-1701页

作者： Kaushalendra Kumar jha UMR Systems Institute Nationale de la Recherche Agronomique2 place Pierre Viala34060 MontpellierFrance Technical Forestry Indian Institute of Forest ManagementBhopalIndia

Poplar is useful in different climates for bioenergy production and carbon sequestration when planted as a single species or in agroforestry. Europe has large areas potentially suitable for poplar forestry and a bioenergy policy that would encourage poplar forestry. In this study I estimated biomass production and carbon sequestration in poplar monoculture plantation and poplar-wheat agroforestry, in the Mediterranean region of France. A single-tree harvesting method was used to estimate biomass and an empirical conversion factor was adopted to calculate sequestered carbon. Total biomass was higher in agroforestry trees(1223 kg tree) than in monoculture plantation trees(1102 kg tree).Aboveground and belowground biomass distributions were similar in both cases(89 and 88% aboveground, and 11 and12% belowground, respectively in agroforestry and monoculture). The partitioning of total biomass in an agroforestry tree in leaves, branch, and trunk(aboveground), and fine roots, medium roots, coarse roots and underground stem(belowground) was 1,22,and 77,and 6,9, 44 and 40%,respectively. Except for branch and trunk, all other compartments were similarly distributed in a monoculture *** of C was higher in agroforestry trees(612 kg tree)than in monoculture trees(512 kg tree). In contrast, C storage on a per hectare basis was lower in agroforestry(85 Mg ha) than in monoculture(105 Mg ha) due to the lower density of trees per hectare in agroforestry(139 trees in agroforestry vs 204 trees in monoculture). On a per hectare basis, soil C stocks pattern were similar to per tree stocking:They were higher in agroforestry at 330 Mg hathan in monoculture 304 Mg ha. Higher C accumulation by agroforestry has a direct management implication in the sense that expanding agroforestry into agriculture production areas with short rotation and fast growing trees like poplar would encourage quicker and greater C sequestration. This could simultaneously fulfil the requirement of bioenergy

关键词： Populus euramericana Wood volume and density Root:shoot ratio Vegetation and soil carbon System efficiency

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Dietary fiber in poultry nutrition and their effects on nutrient utilization,performance,gut health,and on the environment:a review

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Journal of Animal Science and Biotechnology 2022年第1期13卷 1-16页

作者： Rajesh jha.Pravin Mishra Department of Human Nutrition Food and Animal SciencesCollege of Tropical Agriculture and Human ResourcesUniversity of Hawaii at ManoaHonoluluHI 96822USA

Dietary fiber(DF)was considered an antinutritional factor due to its adverse effects on feed intake and nutrient ***,with increasing evidence,scientists have found that DF has enormous impacts on the gastrointestinal tract(GIT)development,digestive physiology,including nutrient digestion,fermentation,and absorption processes of *** may help maintain the small and large intestine’s integrity by strengthening mucosal structure and functions and increasing the population and diversity of commensal bacteria in the *** DF content benefits digestive physiology by stimulating GIT development and enzyme *** the inclusion of fiber at a moderate level in diets also alters poultry growth *** improves gut health by modulating beneficial microbiota in the large intestine and enhancing immune ***,determining the source,type,form,and level of DF inclusion is of utmost importance to achieve the above-noted *** paper critically reviews the available information on dietary fibers used in poultry and their effects on nutrient utilization,GIT development,gut health,and poultry *** these functions will help develop nutrition programs using proper DF at an appropriate inclusion level that will ultimately lead to enhanced DF utilization,overall health,and improved poultry growth ***,this review will help researchers and industry identify the sources,type,form,and amount of DF to be used in poultry nutrition for healthy,costeffective,and eco-friendly poultry production.

关键词： Chicken Dietary fiber Environment Gastrointestinal tract Immunity Intestinal microbiota

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Temporal patterns of storage and flux of N and P in young Teak plantations of tropical moist deciduous forest,India

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Journal of Forestry Research 2014年第1期25卷 75-86页

作者： Kaushalendra Kumar jha Technical Forestry Indian Institute of Forest Management

Teak （Tectona grandis Linn. f.） ranks among the top five tropical hardwood species and is being promoted for use in plantations in its non-native range due to its high economic value. However, there is a general lack of data on ecosystem functioning of teak plantations. We aimed at understanding storage and flux of nutrients related to young plantations of teak. Cycling of nitrogen （N） and phosphorus （P） in a chronosequence of plantations （1, 5, 11, 18, 24 and 30 years） was studied in the Moist Deciduous Forest Region of North India with the objective of investigating the nutrient cycling pattern at younger age since the current trend of harvesting age of the species in several tropical countries is being drastically reduced for quick return from this high value crop. Standing state, nutrient uptake, nutrient return and nutrient retransloca-tion in these plantations were estimated by tree harvesting and chemical analysis methods. The range of total standing nutrient across all these plantations was 20.3 to 586.6 kg？ha-1 for N and 5.3 to 208.8 kg？ha-1 for P. Net uptake of N ranged from 19.4 to 88.9 kg？ha-1？a-1 and P from 3.8 to 18.1 kg？ha-1？a-1. Retranslocation of N and P among all the stands ranged from 8.7 to 48.0 kg？ha-1？a-1 and 0.01 to 3.5 kg？ha-1？a-1, respectively. Range of total nutrient return was 25.8 to 91.3 kg？ha-1？a-1 for N and 2.7 to 10.1 kg？ha-1？a-1 for P. N and P use efficiency was between 107.4 and 192.5 g dry organic matter （OM） g-1N, and 551.9 and 841.1 g OM g-1P, respec-tively. The turnover time ranged from 2.04-13.17 years for N and be-tween 2.40-22.66 years for P. Quantity of N and P in the soil nutrient pool ranged from 2566.8 to 4426.8 kg？ha-1 and 372 to 520 kg？ha-1, re-spectively. Storage and flux of components in different plant parts of different aged plantations were assessed and depicted in compartment models. Percentage storage in soil, litter and vegetation ranged from 82% to 99%, 0.6% to 2.4% and 0.5% to 15% for N, respectively, and from

关键词： nutrient uptake standing state return turnover time nutrient use efficiency compartment model harvest loss Tectona grandis

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Carbon storage and sequestration rate assessment and allometric model development in young teak plantations of tropical moist deciduous forest, India

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Journal of Forestry Research 2015年第3期26卷 589-604页

作者： Kaushalendra Kumar jha Technical Forestry Indian Institute of Forest ManagementPO Box No. 357 Nehru Nagar Bhopal 462 003 MP India

Carbon （C） sequestration through plantations is one of the important mitigation measures for rising levels of carbon dioxide and other greenhouse gases in the atmosphere. This study aimed to assess C stocks and their sequestration rate, and to develop allometric models for estimation of C stocking in age-series young teak （Tectona grandis） planta- tions （1, 5, 11, 18, 24 and 30 years） by using biomass and productivity estimation and regression, respectively. These plantations were raised in tropical moist deciduous forests of Kumaun Himalayan tarai. Total C stocks estimated for these plantations were 1.6, 15.8, 35.4, 39.0, 61.5 and 73.2 Mg ha-1, respectively. Aboveground and belowground C storage in- creased with increasing plantation age; however, the range of their percentage contribution showed little variation （87.8-88.2 and 11.7-12.7 %, respectively）, The rate of C sequestration for these respective plantations was 1.06, 6.95, 5.46, 5.42, 3.39 and 5.37 Mg ha-1 a-1. Forty percent of the aboveground annual storage was retained in the tree while 60 % was released in the form of foliage, twigs, and fruit litter. In the case of total （tree） annual production, 43 % was retained while 57 % was released as litter including root. C stock, C sequestration rate, accumulation ratio （1.4-18.1）, root：shoot C ratio （0.61--0.13） and production efficiency （0.01-0.18） were comparable to some previous reports for other species and forests. These data could be useful in deciding the harvesting age for young teak with respect to C storage and sequestrationrate. Four allometric models using linear regression equations were developed between biomass （twice the C stock） and diameter, girth, and height of the tree at different ages. The diameter model was found more suitable for C stock predic- tion in similar areas.

关键词： Age series Biomass Carbon budget DBH Productivity Production ratios Regression equations -Tectona grandis

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HIGH ORDER ACCURATE QUINTIC NONPOLYNOMIAL SPLINE FINITE DIFFERENCE APPROXIMATIONS FOR THE NUMERICAL SOLUTION OF NON-LINEAR TWO POINT BOUNDARY VALUE PROBLEMS

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International Journal of Modeling, Simulation, and Scientific Computing 2014年第1期5卷 132-147页

作者： NAVNIT jha Department of Mathematics South Asian University Chanakyapuri New Delhi-110021India

We develop a new sixth-order accurate numerical scheme for the solution of two point boundary value *** scheme uses nonpolynomial spline basis and high order finite difference *** the help of spline functions,we derive consistency conditions and it is used to derive high order discretizations of the first *** resulting difference schemes are solved by the standard Newton’s method and have very small computing *** new method is analyzed for its convergence and the efficiency of the proposed scheme is illustrated by convection-diffusion problem and nonlinear Lotka–Volterra *** order of convergence and maximum absolute errors are computed to present the utility of the new scheme.

关键词： Maximum absolute errors order of convergence trigonometric spline Lotka-Volterra equation convection-diffusion equations

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Structural reliability analysis using a hybrid HDMR-ANN method

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Journal of Central South University 2017年第11期24卷 2532-2541页

作者： Bhaw Nath jha.LI Hong-shuang Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicles Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A new hybrid method is proposed to estimate the failure probability of a structure subject to random parameters. The high dimensional model representation(HDMR) combined with artificial neural network(ANN) is used to approximate implicit limit state functions in structural reliability analysis. HDMR facilitates the lower dimensional approximation of the original limit states function. For evaluating the failure probability, a first-order HDMR approximation is constructed by deploying sampling points along each random variable axis and hence obtaining the structural responses. To reduce the computational effort of the evaluation of limit state function, an ANN surrogate is trained based on the sampling points from HDMR. The component of the approximated function in HDMR can be regarded as the input of the ANN and the response of limit state function can be regarded as the target for training an ANN surrogate. This trained ANN surrogate is used to obtain structural outputs instead of directly calling the numerical model of a structure. After generating the ANN surrogate, Monte Carlo simulation(MCS) is performed to obtain the failure probability, based on the trained ANN surrogate. Three numerical examples are used to illustrate the accuracy and efficiency of the proposed method.

关键词： high dimensional model representation structural reliability artificial neural network failure probability

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Strategies to modulate the intestinal microbiota and their effects on nutrient utilization, performance, and health of poultry

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Journal of Animal Science and Biotechnology 2019年第3期10卷 529-539页

作者： Sudhir Yadav Rajesh jha Department of Human Nutrition Food and Animal Sciences College of Tropical Agriculture and Human Resources University of Hawaii at Manoa

Poultry is widely produced and consumed meat *** demand is expected to continue increasing to meet the animal protein requirement for ever-increasing human ***,the challenge that poultry scientists and industry face are to produce sufficient amount of poultry meat in the most efficient *** the past,using antibiotics to promote the growth of poultry and manage gut microbiota was a ***,due to concerns over potential fatalistic impacts on food animals and indirectly to humans,their use as feed additives are banned or regulated in several *** this changed context,several alternative strategies have been proposed with some success that mimics the functions of antibiotics as growth promoters and modulate gut microbiota for their beneficial *** include the use of probiotics,prebiotics,organic acids,and exogenous enzyme,among *** microbiota and their metabolic products improve nutrient digestion,absorption,metabolism,and overall health and growth performance of *** paper reviews the available information on the effect of feed additives used to modulate intestinal microbiota of poultry and their effects on overall health and growth *** these functions and interactions will help to develop new dietary and managerial strategies that will ultimately lead to enhanced feed utilization and improved growth performance of *** review will help future researchers and industry to identify alternative feed ingredients having properties like prebiotics,probiotics,organic acids,and exogenous enzymes.

关键词： Enzymes Microbiota Organic acids Poultry Prebiotics Probiotics

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Palaeogeographic reconstruction of a fluvio-marine transitional system in Narmada rift basin, India——Implications on Late Cretaceous global sea-level rise

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Journal of Palaeogeography 2021年第1期10卷 76-97页

作者： Biplab Bhattacharya Suparna jha.Prantik Mondal Department of Earth Sciences Indian Institute of TechnologyRoorkee 247667India Geological Survey of India Jabalpur 482003India

Rising sea-levels in tectonically active epicontinental basins often lead to varied depositional settings and palaeogeography, mostly influenced by the net accommodation resulting from mutual interference of the extent and nature of landward encroachment by the sea and the net sedimentation. The Cenomanian Nimar Sandstone Formation, Bagh Group, Narmada rift basin, uniquely portrays the effect of sea-level rise within an intra-cratonic setting and attributes to the corresponding palaeogeographic changes in west-central India. An integrated sedimentological–sequence-stratigraphic study of the broadly fining-upward Nimar Sandstone Formation(thickness~ 20–30 m) depicts the actual nature of changeover from a fluvial to a marine-dominated transitional depositional setting. Detailed sedimentological study reveals total seventeen facies, grouped in five facies associations, viz., the channel-fill facies association(FA-1), the overbank facies association(FA-2), the fluvial-dominated fluvio-tidal facies association(FA-3), the tide-dominated fluvio-tidal facies association(FA-4), and the shoreface facies association(FA-5). Overall facies architecture indicates a west-to-eastward marine encroachment, resulting in stacking of three distinct palaeo-depositional conditions:(i) an initial fluvial system with channel and overbank, changing into a tideinfluenced fluvial bay-head delta in the inner estuary, followed by(ii) marine encroachment leading to a tidedominated central estuary with inter-to sub-tidal settings, and finally,(iii) with further intense marine encroachments, a wave-reworked open shore condition in the outer estuary zone. The overall fining-up succession with a systematic change from fluvial to marine-dominated depositional systems points to a landward shift of the shoreline, signifying a major transgressive event correlated to the Cenomanian global sea-level rise. Characteristic stratal stacking patterns point to four coarsening-and fining-up hemicycles, embedded w

关键词： Late Cretaceous Fluvial-estuary transition Nimar Sandstone Formation Bagh Group Narmada rift basin Transgressive–regressive cycles Global sea-level

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Finite element model to study the effect of exogenous buffer on calcium dynamics in dendritic spines

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International Journal of Modeling, Simulation, and Scientific Computing 2014年第2期5卷 1-12页

作者： Amrita jha.Neeru Adlakha Department of Applied Mathematics and Humanities S.V.National Institute of Technology Surat Gujarat-395007

Dendritic spine plays an important role in calcium regulation in a neuron *** serves as a storage site for synaptic strength and receives input from a single synapse of *** order to understand the calcium dynamics in a neuron cell,it is crucial to understand the calcium dynamics in dendritic *** this paper,an attempt has been made to study the calcium dynamics due to the exogenous buffers,in dendritic spines with the help of a sectional *** compartments of dendritic spines are discretized using triangular *** boundary conditions have been *** element method has been employed to obtain the solution in the region for a two-dimensional unsteady state *** 7.11 is used for simulation of the problem and numerical *** numerical results have been used to study the effect of exogenous buffers on calcium distribution in dendritic spines.

关键词： Diffusion coefficient buffers variational form finite element method

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Sulfide oxidation in fluidized bed bioreactor using nylon support material

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Journal of Environmental Sciences 2012年第3期24卷 512-519页

作者： Varsha Midha M K jha.Apurba Dey Department of Chemical Engineering National Institute of TechnologyJalandhar 144011India Department of Biotechnology National Institute of Technology DurgapurIndia

A continuous fluidized bed bioreactor （FBBR） with nylon support particles was used to treat synthetic sulfide wastewater at different hydraulic retention time of 25, 50 and 75 min and upflow velocity of 14, 17 and 20 m/hr. The effects of upflow velocity, hydraulic retention time and reactor operation time on sulfide oxidation rate were studied using statistical model. Mixed culture obtained from the activated sludge, taken from tannery effluent treatment plant, was used as a source for microorganisms. The diameter and density of the nylon particles were 2-3 mm and 1140 kg/m3, respectively. Experiments were carried out in the reactor at a temperature of （30 ± 2）°C, at a fixed bed height of 16 cm after the formation of biofilm on the surface of support particles. Biofilm thickness reached （42 ± 3） μm after 15 days from reactor start-up. The sulfide oxidation, sulfate and sulfur formation is examined at all hydraulic retention times and upflow velocities. The results indicated that almost 90%-92% sulfide oxidation was achieved at all hydraulic retention times. Statistical model could explain 94% of the variability and analysis of variance showed that upflow velocity and hydraulic retention time slightly affected the sulfide oxidation rate. The highest sulfide oxidation of 92% with 70% sulfur was obtained at hydraulic retention time of 75 min and upflow velocity of 14 m/hr.

关键词： biofilm fluidized bed bioreactor mixed culture sulfide oxidation

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