1,888 research outputs found
The importance of the classical channel in the impurity transport of optimized stellarators
In toroidal magnetic confinement devices, such as tokamaks and stellarators,
neoclassical transport is usually an order of magnitude larger than its
classical counterpart. However, when a high-collisionality species is present
in a stellarator optimized for low Pfirsch-Schl\"uter current, its classical
transport can be comparable to the neoclassical transport. In this letter, we
compare neoclassical and classical fluxes and transport coefficients calculated
for Wendelstein 7-X (W7-X) and Large Helical Device (LHD) cases. In W7-X, we
find that the classical transport of a collisional impurity is comparable to
the neoclassical transport for all radii, while it is negligible in the LHD
cases, except in the vicinity of radii where the neoclassical transport changes
sign. In the LHD case, electrostatic potential variations on the flux-surface
significantly enhance the neoclassical impurity transport, while the classical
transport is largely insensitive to this effect in the cases studied.Comment: 10 pages, 2 figure
A MICROCOMPUTER MODEL FOR IRRIGATION SYSTEM EVALUATION
ICEASE (Irrigation Cost Estimator and System Evaluator) is a microcomputer model designed and developed to meet the need for conducting economic evaluation of adjustments to irrigation systems and management techniques to improve the use of irrigated water. ICEASE can calculate the annual operating costs for irrigation systems and has five options that can be used to economically evaluate improvements in the pumping plant or the way the irrigation system is used for crop production.Crop Production/Industries,
Greenhouse gas emissions mitigation in more sustainable agroecosystems in Cerrado.
In this work, we show that the transition to more sustainable rural production can mitigate greenhouse gas (GHG) emissions by agroecosystems without compromising revenues, particularly in the Cerrado region.(Embrapa Gado de Corte. Documentos, 216). Coordenador Roberto Giolo de Almeida. II SIGEE. Disponível em: . Acesso em: 30 nov. 2016
Farmer attitudes to injurious pecking in laying hens and to potential control strategies
PublishedFarmers' recognition of health and welfare problems, and their responses to related intervention programmes, such as those to reduce injurious pecking in hens, directly influence the welfare of animals in their care. Changing those responses can be achieved through a re-positioning of social drivers as well as from individual behaviour. This study begins by considering how certain levels of plumage damage become normalised while others might be considered unacceptable. Drawing upon in-depth farmer interviews, the study investigates how management practices for addressing the issue of injurious pecking are developed and enacted, looking at the relative influence of intrinsic and extrinsic individual behavioural factors. Twelve farmers with varied uptake of evidence-based management strategies designed to reduce levels of injurious pecking were interviewed. Although farmers ranked images of flocks with various levels of plumage damage in a similar order to scientists, their perception of levels of injurious pecking in their own flocks varied, and was not consistently associated with the actual levels measured. Most farmers recognised both financial and welfare implications of injurious pecking and expressed pride in having a good-looking flock. The popular management strategies were those designed to redirect pecking to other objects, whereas a substantial barrier to uptake was the perception of creating other problems: for example, mislaid eggs if early access to litter and range were adopted. To achieve uptake of knowledge that improves animal welfare on-farm, it may be necessary both to shift the norms perceived as acceptable, and to overcome barriers to change that include lack of time and understanding, by providing impartial advice and facilitation of ownership of the issues.Tubney Charitable Trus
Facilitating practice-led co-innovation for the improvement in animal welfare
This is the author accepted manuscript. The final version is available from SAGE Publications via the DOI in this recordUsing the egg-laying-hen sector as a case study, the European Union-funded ‘Hennovation’ thematic network has been testing mechanisms to enable practice-led innovation through the establishment of 19 innovation networks of farmers and within the laying-hen processing industry, supported by existing science and market-driven actors. These networks were facilitated to proactively search for, share and use new ideas to improve hen welfare, efficiency and sustainability. This article provides insights into the tools used, including a framework for the facilitation of practice-led collaborative innovation processes. This framework was developed through participatory action research to monitor network performance and self-reflection by facilitators. Practice-led innovation processes are network specific and evolve as the actors within the network come together to share common problems, experiment with possible solutions and learn. The participatory and iterative nature of this process leads to uncertainty in process and end results. This raises methodological challenges in the management of such processes and requires a flexible and adaptive management approach focusing on learning and reflection.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The article draws upon research and discussions conducted under the HENNOVATION project, a H2020 EU collaborative research project with six academic partners funded under the topic ‘Innovative, Sustainable and Inclusive Bioeconomy’ ISIB-2-2014/ 2015: Closing the research and innovation divide: the crucial role of innovation support services and knowledge exchange. Grant agreement no 652638
Campus Incivility and Free Speech: A Contemporary Dilemma
The issue of free speech on college campuses is as old as education itself and as current as today\u27s news. Institutions of higher education often find themselves torn between their desire to create environments where students and professors remain physically safe and their mission to protect academic freedom and the right of free speech. This interactive presentation will provide academic leaders with the skill set to increase the likelihood that constructive conflicts between ideas don\u27t escalate into destructive, violent acts
A Role for NKG2D in NK Cell–Mediated Resistance to Poxvirus Disease
Ectromelia virus (ECTV) is an orthopoxvirus (OPV) that causes mousepox, the murine equivalent of human smallpox. C57BL/6 (B6) mice are naturally resistant to mousepox due to the concerted action of innate and adaptive immune responses. Previous studies have shown that natural killer (NK) cells are a component of innate immunity that is essential for the B6 mice resistance to mousepox. However, the mechanism of NK cell–mediated resistance to OPV disease remains undefined. Here we show that B6 mice resistance to mousepox requires the direct cytolytic function of NK cells, as well as their ability to boost the T cell response. Furthermore, we show that the activating receptor NKG2D is required for optimal NK cell–mediated resistance to disease and lethality. Together, our results have important implication towards the understanding of natural resistance to pathogenic viral infections
Replication of Molluscum Contagiosum Virus
AbstractMolluscum contagiosum virus (MCV) infects preadolescent children and sexually active adults, frequently causing a disfiguring cutaneous disease in immunosuppressed HIV-infected individuals. The development of an efficacious treatment regime has been hampered by the failure to replicate the virus in the laboratory. Here we report the first demonstration of MCV replication in an experimental system. In human foreskin grafts to athymic mice, MCV induced morphological changes which were indistinguishable from patient biopsies and included the development and migration of molluscum bodies containing mature virions to the epidermal surface
Modelagem sistêmica do ciclo de vida do aguapé no Pantanal e análise do uso desta biomassa para a produção de bio-óleo e bio-fertilizante.
O Pantanal ocupa uma área extensa do Brasil em torno de 140.000 km²; seus ecossistemas são caracterizados por áreas com alagamento periódico, campos inundados constantemente e ambientes aquáticos naturais com lagoas (baías), rios e canais (vazantes e corixos); não existem quedas d? água para a geração de energia elétrica dentro da bacia. Em virtude das áreas alagadas existem poucas vias para o abastecimento de combustíveis para as fazendas produtoras que, assim, dependem fortemente de diesel e lenha como fonte de energia. Além disso, as cidades da região dependem da energia elétrica originária de outros estados da federação e a produção industrial (cimento e ferro gusa) é baseada em carvão vegetal, cuja origem é questionável, possivelmente do desmatamento do Cerrado. O uso de fontes alternativas de biomassa produzidas localmente poderia amenizar a carência energética no Pantanal. O aguapé, que se desloca nas lagoas e rios do Pantanal na forma de ilhas flutuantes, pode ser uma fonte alternativa de biomassa para a obtenção de combustíveis sólidos, líquidos e gasosos renováveis produzidos e distribuídos localmente. Esta pesquisa objetivou uma análise do ciclo de vida do aguapé na região de Corumbá mediante estudos teóricos que permitiram modelar e simular a dinâmica de crescimento (nas baías e margens dos rios) e de decaimento do aguapé (decomposição), elaborar cenários de colheita sustentável e dos mecanismos de remoção de nutrientes pelo aguapé em diferentes épocas do ano e realizar a avaliação emergética da produção natural de biomassa e de produtos derivados da conversão termoquímica desta biomassa, bio-óleo e bio-carvão. O estudo foi complementado com uma avaliação econômica de uma unidade industrial de pirólise rápida de biomassa. Os resultados obtidos permitem que tomadores de decisão avaliem de modo sistêmico a viabilidade ambiental e econômica da criação de um sistema para extração e aproveitamento de biomassa de aguapé. Os níveis de colheita estudados e os indicadores emergéticos e econômicos apontam para a viabilidade ecológica e econômica de um sistema operando com extração de 1% da biomassa de aguapé escoada no rio Paraguai. Para níveis maiores de extração, os resultados trazem à tona questões que requerem estudos adicionais a fim de garantir uma visão ecológica sobre a exploração de recursos naturais do Pantanal que é um importante provedor de serviços ambientais. As interferências na região devem ser baseadas em mecanismos de monitoramento contínuo dos impactos ambientais e socioeconômicos da atividade antrópica e em premissas de responsabilidade socioambiental no longo prazo.Dissertação (Mestrado em Engenharia de Alimentos) - Universidade Estadual de Campinas, Campinas, SP. Co-orientador: Dr. Ivan Bergier Tavares de Lima
Systemic behavior of a Brazilian municipality whose economy is based on agricultural commodities.
The municipality evaluated is São Gabriel do Oeste, located in the state of Mato Grosso do Sul, Brazil. In the 1960's the region was occupied by migrants from southern Brazil who have converted native vegetation (savanna) into extensive cattle and monocrops (coffee, cotton, soybeans and corn, successively), and more recently intensive swine was introduced. The following emergy indicators were calculated for the current municipal situation: Renewability (%R): 8%; Emergy yield ratio (EYR): 14; Emergy investment ratio (EIR): 0.08; Environmental loading ratio (ELR): 11; Emergy exchange ratio (EER): 13 and Transformity of the commodities: 8x105seJ.J-1. The very low %R and high environmental pressure (ELR) signalize that the municipality's economy is highly dependent on external inputs. Above all, there is a high loss of system internal stocks (soil) and the high EYR obtained is directly related to this predatory land use. The emergy value of the soil loss is 83% of the total emergy, which is an environmental imbalanced situation. The main land use in São Gabriel do Oeste, accounting for 39% of the territory, is extensive cattle farming that demands few agricultural inputs, what explains the very low EIR. The EER shows that the rural area is subsidizing urban economies that import products from the study area. The real value of the agricultural products should be 13 times the market value of such commodities to be considered as a fair trade. The inclusion of soil loss as a negative externality shows that (in economic terms) the amount of soil lost by erosion and leaching (4,149x106 emUSD.year-1) corresponds to 46% of the total production monetary value (9,018x106 emUSD.year-1). The emergy diagnosis shows that the business model established for commodities producers is highly dependent on the external market, which does not remunerate the imported resources accordingly to its real value. To settle this situation, a dialogue between farmers, consumers and authorities should be established. The latter two should involve not only local representatives as well as players of the importing countries.BIWAES 2015
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