Simulating farm income under the current soil management regime in the mid-hills of Nepal

Farmers in the mid-hills of Nepal follow diverse farming systems. The peri-urban area of this region, where population density is higher, faces several problems in farming. While hills suffer from erosion because they are erodible, the peri-urban areas face the problem of decline in factor productivity, particularly in intensively cultivated farmlands. The present study is concerned with simulating farm income on a regional scale based on soil management practices. Spatial explicit simulation shows that the loss of farm income due to degradation is substantially higher in hills while it is lower in valley bottoms. Strategy formulation and testing in the spatial environment indicates that Geographic Information System is an appropriate methodological tool for simulating the consequences of particular interventions

Environmental impact of organic agriculture in temperate regions

Can organic agriculture elaborate a scientifically based, resource-efficien and agroecological approach to low-input farm management? This review examines the literature from temperate regions, with a particular emphasison Canadian and USstudies that relate to environmental and ecological impacts of organic agriculture with respect to (i )soil organic matter storage, (ii) soil quality/soil health, (iii) nutrient loading and risks of off-farm nutrient and agrochemical losses, (iv) biodiversity and (v) energy use and global warming potential. The context and implications of semi-arid conditions and low soil P levels, common to many organic farms in North America, and wide spread adoption of genetically engineered crops in conventional production, is also considered. The consensus of the data available to date indicates the distinctiveness of cropping, flora and habitat diversity, soil management regime, nutrient intensity and use efficiency and energy, and pesticide use in organic farming confer important environmental and ecological benefits. These include maintenance of soil organic matter and added return of carbon to soil, improved soil health, reduced off-farm nitrogen and phosphorus losses, enhanced vegetative and wildlife (bird) biological diversity, extended some times to other taxa depending on landscape context, improved support for pollinators and pollination and reduced energy use and improved energy efficiency. The continued evolution of organic agriculture to a more outcomes-based, agroe cological production system will require an expanded multi-disciplinary research effort, linked ideally to support from consumers and policy-makers on the basis of renewed under-standing of its potential contribution to global environmental sustainability

Effect of Hydraulic Resistivity on a Weakly Nonlinear Thermal Flow in a Porous Layer

Heat and mass transfer through porous media has been a topic of research interest because of its importance in various applications. The flow system in porous media is modelled by a set of partial differential equations. The momentum equation which is derived from Darcy’s law contains a resistivity parameter. We investigate the effect of hydraulic resistivity on a weakly nonlinear thermal flow in a horizontal porous layer. The present study is a realistic study of nonlinear convection flow with variable resistivity whose rate of variation is arbitrary in general. This is a first step for considering more general problems in applications that involve variable resistivity that may include both variations in permeability and viscosity of the porous layer. Such problems are important for understanding properties of underground flow, migration of moisture in fibrous insulations, underground disposal of nuclear waste, welding process, petrochemical generation, drug delivery in vascular tumor, etc. Using weakly non-linear procedure, the linear and first-order systems are derived. The critical Rayleigh number and the critical wave number are obtained from the linear system using the normal mode approach for the two-dimensional case. The linear and first-order systems are solved numerically using the fourth-order Runge-Kutta and shooting methods. Numerical results for the temperature are presented in tabular and graphical forms for different resistivities. Through this study, it is observed that a stabilizing effect on the dependent variables occurs in the case of a positive vertical rate of change in resistivity, whereas a destabilizing effect is noticed in the case of a negative vertical rate of change in resistivity. The results obtained indicate that the convective flow due to the buoyancy force is more effective for weaker resistivity

On Temporal Instability of Electrically Forced Axisymmetric Jets with Variable Applied Field and Nonzero Basic State Velocity

The problem of instability of electrically forced axisymmetric jets with respect to temporally growing disturbances is investigated computationally. We derive a dispersion relation based on the relevant approximated versions of the equations of the electro-hydrodynamics for an electrically forced jet flow. For temporal instability, we find in the realistic cases of the non-zero basic state velocity that the growth rate of the unstable mode is unaffected by the value of the basic state velocity. However, the non-zero value of the basic state velocity affects significantly the period of the unstable mode in the sense that it decreases the period, and the rate of increase of the frequency with respect to the axial wave number increases with the basic state velocity. It is also observed from numerical investigations that there are two modes of instability for small values of the wavenumber

Mathematical modeling of nonlinear blood glucose-insulin dynamics with beta cells effect

We consider mathematical modeling of blood glucose-insulin regulatory system with the additional effect of the secreted insulin by the pancreatic beta cells and in the presence of an external energy input to such system. Such modeling system is investigated to determine the time-dependent nonlinear dynamics that take place by the quantities, which represent the glucose and insulin concentrations in the blood, insulin action as well as in the absence or presence of secreted insulin due to the pancreatic beta cells. Using both analytical and numerical procedures, we determine such quantities versus time for both diabetes patients and normal human and for different values of the parameters. We find that the nonlinear effect of the dynamics of the investigated regulatory system increases the values of the insulin action and the glucose and insulin concentrations. In the absence of the beta cells effects, which can correspond to the case of severe type 1 diabetes, the plasma glucose is higher and the insulin action and the insulin concentration are less active than the corresponding ones for the case in the presence of beta cells, which is relevant for type 2 diabetes or moderate type 1 diabetes patients. For the present system, smaller values of the parameters of the model, which represent kinetics of the glucose and insulin action, insulin sensitivity, insulin secretion enhancement and the plasma insulin decay rate, can lead to notably lower values of the glucose concentration. In the presence of the secreted insulin by the pancreatic beta cells the insulin action and the insulin concentration are more effective to reduce the blood glucose, which can help to improve the diabetes patient’s health

Effect of Graded Levels of Condensed Tannin (CT) from \u3cem\u3eMimosa pudica\u3c/em\u3e on \u3cem\u3ein-Vitro\u3c/em\u3e Methane Production

Livestock in the country are primarily being fed on fibrous feed resulted in high enteric methane (CH4) emission along with low nutrients availability to host animal. Rumen methano genesis is necessary for the host system as this process ensure the removal of fermentative H2 through the reduction of CO2 into CH4. At the same time this process is wasteful because the emission also represents a loss of dietary energy (6-12% of gross energy intake) apart from contributing to global warming. Worldwide livestock contribute around 90-95 Tg methane to the pool with a contribution of 12-13% from the Indian livestock. Various nutritional and other approaches have been attempted with highly variable success rate in the country and elsewhere for the enteric methane amelioration. The cost of the item used for the mitigation purpose, adaptation of ruminal microbes and toxicity to either host animal or inhabiting microbes are few important criteria for an economic, sustainable and effective amelioration approach (Malik et al. 2015). Herbal materials are being used by the peoples since ages; however, their anti-methanogenic effect is recently established. The anti-methanogenic effect of different herbal materials mainly lies in their secondary metabolites which are highly effective even at very low concentration (Bhatta et al., 2014). Keeping these facts in view, a study was carried to ascertain the effect of varying levels of CT on in vitro total gas and methane production

Effect of Selected Tanniniferous Leaves on \u3cem\u3ein Vivo\u3c/em\u3e Enteric Methane Emission in Sheep

Concentration of methane is continuously increasing in atmosphere and now almost 155% (IPCC, 2007) more than that recorded during pre-industrial era. Livestock production is a major sector accountable for high methane emission into atmospheric pool. World’s livestock is contributing around 15% of total atmospheric methane on annual basis feeds (Moss et al., 2000). Additionally, methane emission from ruminants leads to a loss of 2 to 15% of the dietary energy (Holter and Young, 1992). Due to these two crucial issues, researchers are working tirelessly to find a suitable and effective way for enteric methane amelioration accompanied with minimal inputs. So far numerous interventions have been tried with variable results, but due to one or another reason the search for effective strategy is on the priority of animal scientist. One of the possible approaches for enteric methane amelioration may be the use of plant secondary metabolites which are being traditionally used by the people since ages. Under the ICAR sponsored outreach project on Estimation of methane emission under different feeding systems and development of mitigation strategies more than 1700 feed, herbs and grasses samples were screened through in vitro gas production technique at different participating centres and finally selected few plant & herbs for evaluating the secondary metabolites on in vivo enteric methane emission. Three selected tanniniferous leaves were evaluated for their effect on enteric methane emission and feed fermentability in adult sheep

Oxidation mechanism in metal nanoclusters: Zn nanoclusters to ZnO hollow nanoclusters

Zn nanoclusters (NCs) are deposited by Low-energy cluster beam deposition technique. The mechanism of oxidation is studied by analysing their compositional and morphological evolution over a long span of time (three years) due to exposure to ambient atmosphere. It is concluded that the mechanism proceeds in two steps. In the first step, the shell of ZnO forms over Zn NCs rapidly up to certain limiting thickness: with in few days -- depending upon the size -- Zn NCs are converted to Zn-ZnO (core-shell), Zn-void-ZnO, or hollow ZnO type NCs. Bigger than ~15 nm become Zn-ZnO (core-shell) type: among them, NCs above ~25 nm could able to retain their initial geometrical shapes (namely triangular, hexagonal, rectangular and rhombohedral), but ~25 to 15 nm size NCs become irregular or distorted geometrical shapes. NCs between ~15 to 5 nm become Zn-void-ZnO type, and smaller than ~5 nm become ZnO hollow sphere type i.e. ZnO hollow NCs. In the second step, all Zn-void-ZnO and Zn-ZnO (core-shell) structures are converted to hollow ZnO NCs in a slow and gradual process, and the mechanism of conversion proceeds through expansion in size by incorporating ZnO monomers inside the shell. The observed oxidation behaviour of NCs is compared with theory of Cabrera - Mott on low-temperature oxidation of metal.Comment: 9 pages, 8 figure

Injury and Mortality in Young Nepalese Migrant Workers: A Call for Public Health Action

Approximately 3.5 million Nepalese are working as migrant workers in the Gulf countries, Malaysia, and India. Every year there are more than 1000 deaths and many hundreds cases of injuries among Nepalese workers in these countries excluding India. A postmortem examination of migrant workers is not carried out in most of these countries, and those with work-related injuries are often sent back to home. Uninsured migrant workers also do not have easy access to health care services in host countries due to the high medical and hospital fees. Greater efforts are needed to protect the health and well-being, labor rights, and human rights of migrant workers from Nepal and other South- Asian nations. There is a need to enforce universal labor laws in these countries and to develop accurate records of mortality and morbidity and their causes