Electron dynamics in planar radio frequency magnetron plasmas: II. Heating and energization mechanisms studied via a 2d3v particle-in-cell/Monte Carlo code

The present work investigates electron transport and heating mechanisms using an (r, z) particle-in-cell (PIC) simulation of a typical rf-driven axisymmetric magnetron discharge with a conducting target. It is shown that for the considered magnetic field topology the electron current flows through different channels in the (r, z) plane: a ``transverse'' one, which involves current flow through the electrons' magnetic confinement region (EMCR) above the racetrack, and two ''longitudinal'' ones. Electrons gain energy from the electric field along these channels following various mechanisms, which are rather distinct from those sustaining dc-powered magnetrons. The longitudinal power absorption involves mirror-effect heating (MEH), nonlinear electron resonance heating (NERH), magnetized bounce heating (MBH), and the heating by the ambipolar field at the sheath-presheath interface. The MEH and MBH represent two new mechanisms missing from the previous literature. The MEH is caused by a reversed electric field needed to overcome the mirror force generated in a nonuniform magnetic field to ensure sufficient flux of electrons to the powered electrode, and the MBH is related to a possibility for an electron to undergo multiple reflections from the expanding sheath in the longitudinal channels connected by the arc-like magnetic field. The electron heating in the transverse channel is caused mostly by the essentially collisionless Hall heating in the EMCR above the racetrack, generating a strong ExB azimuthal drift velocity. The latter mechanism results in an efficient electron energization, i.e., energy transfer from the electric field to electrons in the inelastic range. Since the main electron population energized by this mechanism remains confined within the discharge for a long time, its contribution to the ionization processes is dominant

Poor Thermal Care Practices among Home Births in Nepal: Further Analysis of Nepal Demographic and Health Survey 2011

Introduction - Hypothermia is a major factor associated with neonatal mortality in low and middle income countries. Thermal care protection of newborn through a series of measures taken at birth and during the initial days of life is recommended to reduce the hypothermia and associated neonatal mortality. This study aimed to identify the prevalence of and the factors associated with receiving ‘optimum thermal care’ among home born newborns of Nepal. Methods - Data from the Nepal Demographic and Health Surveys (NDHS) 2011 were used for this study. Women who reported a home birth for their most recent childbirth was included in the study. Factors associated with optimum thermal care were examined using Chi-square test followed by logistic regression. Results - A total of 2464 newborns were included in the study. A total of 57.6 % were dried before the placenta was delivered; 60.3% were wrapped; 24.5% had not bathing during the first 24 hours, and 63.9% were breastfed within one hour of birth. Overall, only 248 (10.7%; 95% CI (8.8 %, 12.9%)) newborns received optimum thermal care. Newborns whose mothers had achieved higher education (OR 2.810; 95% CI (1.132, 6.976)), attended four or more antenatal care visits (OR 2.563; 95% CI (1.309, 5.017)), and those whose birth were attended by skilled attendants (OR 2.178; 95% CI (1.428, 3.323)) were likely to receive optimum thermal care. Conclusion - The current study showed that only one in ten newborns in Nepal received optimum thermal care. Future newborn survival programs should focus on those mothers who are uneducated; who do not attend the recommended four or more attend antenatal care visits; and those who deliver without the assistance of skilled birth attendants to reduce the risk of neonatal hypothermia in Nepal

Institutional Innovations for Building Impact-oriented Agricultural Research, Knowledge and Development Institutions

The central development question in African agriculture is how to catalyze a more competitive, equitable and sustainable agricultural growth within the context of smallholder production systems, inefficient agricultural marketing, inefficient investments by private sector amidst degradation prone natural resources base (Lynam and Blackie, 1994; IAC, 2004; World bank, 2006 ). Concerted scholarly analyses of Science and Technology (S&T) strategies have given birth to Integrated Agricultural Research for Development (IAR4D) an organizing concept of the Innovation Systems Approach (ISA) as the promise holder. It is hypothesized that the generation, diffusion and application of impactful innovations critically depend on systemic integration of knowledge systems that promote communication, interaction and cooperation between agricultural research, education, extension, farmers, private sector and policy regulatory systems. This paper examines how the different institutional innovations arising from various permutations of linkages and interactions of ARD organizations (national, international advanced agricultural research centres and universities) influenced the different outcomes in addressing identified ARD problems. A multi-institutional, multi-disciplinary phased Participatory Action Research approach was used to pool knowledge to address outstanding and emerging challenges in three countries (DRC, Rwanda and Uganda) with 2, 16 and 24 years out of conflict, respectively) of the Lake Kivu Pilot Learning Site. A landmark institutional innovation was the participatory establishment of twelve (12) Innovation Platforms as tools for pooling knowledge across the agricultural business, education, research and extension systems. The knowledge “pool” was to generate, diffuse and apply innovations to reduce transactions costs and create value chain based “win-win” situations. A number of innovations (e.g. International Public Goods-IPGs, market binding contracts, registered brands and/or certification processes, diversity, density and quality of networks/collective action, bulking centres, ICT application and depth of knowledge pools) were initiated. There were major breakthroughs which included bringing on board non-traditional private sector and policy maker partners, overcoming the predominant “farmer handout syndrome”, building consensus and addressing common interest challenge. Making markets work, bringing various stakeholders including universities to the community and vice-versa, appreciation of indigenous knowledge system, propelling collective soil and water conservation and demand/utilization of technologies hitherto on-shelf were other very significant breakthroughs. Sustainable operations of the Innovation Systems knowledge “pool” nurturing institutional learning were ensured through the availability of a “functional body”. The body undertook the social enterprise of organizing farmers and traders, facilitating/brokering ARD organization linkages by using multi-media to build social capital to overcome emergent knowledge, credit, market, technology and resource degradation challenges under different policy regulatory systems

Multicriterion structure/control design for optimal maneuverability and fault tolerance of flexible spacecraft

A multicriterion design problem for optimal maneuverability and fault tolerance of flexible spacecraft is considered. The maneuverability index reflects the time required to perform rest-to-rest attitude maneuvers for a given set of angles, with the postmaneuver spillover within a specified bound. The performance degradation is defined to reflect the maximum possible attitude error after maneuver due to the effect of faults. The fault-tolerant design is to minimize the worst performance degradation from all admissible faults by adjusting the design of the spacecraft. It is assumed that admissible faults can be specified by a vector of real parameters. The multicriterion design for optimal maneuverability and fault tolerance is shown to be well defined, leading to a minimax problem. Analysis for this nonsmooth problem leads to closed-form expressions of the generalized gradient of the performance degradation function with respect to the fault parameters and structural design variables. Necessary and sufficient conditions for the optimum are derived, and the closed-form expressions of the generalized gradients are applied for their interpretation. The bundle method is applicable to this minimax problem. Approximate methods which efficiently solve this minimax problem with relatively little computational difficulties are presented. Numerical examples suggest that it is possible to improve the fault tolerance substantially with relatively little loss in maneuverability.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45242/1/10957_2005_Article_BF02191852.pd

Tobacco industry globalization and global health governance: : towards an interdisciplinary research agenda

Shifting patterns of tobacco production and consumption, and the resultant disease burden worldwide since the late twentieth century prompted efforts to strengthen global health governance through adoption of the Framework Convention on Tobacco Control. While the treaty is rightfully considered an important achievement, to address a neglected public health issue through collective action, evidence suggests that tobacco industry globalization continues apace. In this article we provide a systematic review of the public health literature and reveal definitional and measurement imprecision, ahistorical timeframes, transnational tobacco companies and the state as the primary units and levels of analysis, and a strong emphasis on agency as opposed to structural power. Drawing on the study of globalization in international political economy and business studies, we identify opportunities to expand analysis along each of these dimensions. We conclude that this expanded and interdisciplinary research agenda provides the potential for fuller understanding of the dual and dynamic relationship between the tobacco industry and globalization. Deeper analysis of how the industry has adapted to globalization over time, as well as how the industry has influenced the nature and trajectory of globalization, is essential for building effective global governance responses

Principles, design and processes of integrated agricultural research for development: experiences and lessons from LKPLS under the SSACP

With increasing recognition holding the promise of overcoming the outstanding problems faced byAfrican agriculture, IAR4D faces the danger of being ‘blurred’ by past approaches and falling short of its potential to deliver the desired impacts in diverse multi-stakeholder, biophysical, socio- economic, cultural, technological and market contexts unless its actualisation and working is clearly understood. In this paper, we present the conceptualisation and principles of and knowledge-based experiences and lessons from the implementation of the sub-Saharan Africa Challenge Programme (SSACP) in the Lake Kivu Pilot Learning Site (LKPLS). The presentation covers the formation and facilitation of IPs for the actualisation of IAR4D to evolve mechanisms for the early recognition of interlinked issues in natural resource management, productivity and value addition technologies, markets, gender and policy arrangements. These have autonomously triggered flexible, locally directed interactions to innovate options from within or outside their environment for resolving the challenges, and have moved along a new institutional and technological change trajectory. Emerging lessons point to the endowment of IP members with selfhelp knowledge interactions, training in IAR4D, quality of facilitation and research to be key determinants of the power behind of self-regulating mechanisms