5,712 research outputs found
Structural changes in the Philippine pig industry and their environmental implications:
"Pig production in the Philippines has intensified in the urban and peri-urban areas in response to a radical structural change in the pig industry and a growing demand for pork products. Alongside this rapid growth is the emergence of societal concern about the increasing negative environmental externalities that the industry produces, particularly those related to the disposal of waste and dead animals. Pig producers are said to benefit from negative externalities when they do not bear the full social costs of their business enterprise. Non-internalization of such externalities occurs when pig producers receive payment for their output while not investing in pollution abatement or not making compensatory payments to surrounding communities affected by their production processes. In some cases, producers are able to recycle all nutrients from swine production on-farm through various cropping mechanisms. In other cases, pig production is so large that there is no land to properly dispose of such by-products without some environmental mitigation effort. Failure to implement any sort of measure will most likely lead to an environmental externality. To determine whether a farmer has the ability to utilize all manure produced on-farm, we use a mass balance calculation approach in this paper. Results for the mass balance calculations suggest that, in general, smaller farms generate less excess nutrients per hectare than larger farms. This is because most small-scale pig farms are mixed systems where some croplands are available for nutrient assimilation. Large commercial farms tend to be âpure land-intensiveâ systems. We used a Tobit regression analysis to determine the factors affecting environmental mitigation expenditures of pig farms. Results of the regression showed that smaller farms tend to respond to opportunities to make use of manure as fertilizer on their own farms and crops. For large farms, no single factor significantly influenced mitigation costs. An interpretation of why this is so or what this result implies apparently cannot be achieved without ambiguity. Thus, we do not attempt to do so and we leave the matter for further investigation. With respect to the effects of production arrangement on environmental capture, the factors that significantly influenced mitigation costs varied between independent and contract farms. Only the operation of croplands mattered for independent producers. For contract farms, lands that are classified as agricultural carried the expected positive coefficient sign. Further, farmers in the industrial pig sector, which is concentrated in peri-urban areas favored by market access or feed availability, may consider being located as close as possible to cropland that they can use to dispose of the wastes in pig production. Policy options include zoning, mandatory nutrient management plans, licensing or limiting the number of animals raised per production unit, and contractual agreements between livestock producers and crop farmers. The effectiveness of such regulations will depend largely on the degree to which they are enforced and whether they are accompanied by a well-developed system of education and extension with focus on proper manure management systems and dead animal disposal." from Author's AbstractEnvironmental mitigation, Mass balance, Structural changes, Pig production, Water quality,
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Nasal administration of glutamate decarboxylase (GAD65) peptides induces Th2 responses and prevents murine insulin-dependent diabetes.
We previously demonstrated that a spontaneous Th1 response against glutamate decarboxylase (GAD65) arises in NOD mice at four weeks in age and subsequently T cell autoimmunity spreads both intramolecularly and intermolecularly. Induction of passive tolerance to GAD65, through inactivation of reactive T cells before the onset of autoimmunity, prevented determinant spreading and the development of insulin-dependent diabetes mellitus (IDDM). Here, we examined whether an alternative strategy, designed to induce active tolerance via the engagement of Th2 immune responses to GAD65, before the spontaneous onset of autoimmunity, could inhibit the cascade of Th1 responses that lead to IDDM. We observed that a single intranasal administration of GAD65 peptides to 2-3-wk-old NOD mice induced high levels of IgG1 antibodies to GAD65. GAD65 peptide treated mice displayed greatly reduced IFN gamma responses and increased IL-5 responses to GAD65, confirming the diversion of the spontaneous GAD65 Th1 response toward a Th2 phenotype. Consistent with the induction of an active tolerance mechanism, splenic CD4+ (but not CD8+) T cells from GAD65 peptide-treated mice, inhibited the adoptive transfer of IDDM to NOD-scid/scid mice. This active mechanism not only inhibited the development of proliferative T cell responses to GAD65, it also limited the expansion of autoreactive T cell responses to other beta cell antigens (i.e., determinant spreading). Finally, GAD65 peptide treatment reduced insulitis and long-term IDDM incidence. Collectively, these data suggest that the nasal administration of GAD65 peptides induces a Th2 cell response that inhibits the spontaneous development of autoreactive Th1 responses and the progression of beta cell autoimmunity in NOD mice
Effects of weight loss interventions for adults who are obese on mortality, cardiovascular disease and cancer : a systematic review and meta-analysis
We thank Associate Professor Andrew Grey for helping to resolve discrepancies in data extraction and interpretation for cardiovascular events and cancer events. We thank trialists from 16 studies for clarifying or providing additional information for this review [Andrews 2011, Aveyard 2016, Bennett 2012, de Vos 2014, Finnish Diabetes Prevention Study 2009, Goodwin 2014, Green 2015, Horie 2016, Hunt (FFIT) 2014, Katula 2013, Li (Da Qing) 2014, Logue 2005, Ma 2013, OâNeil 2016, Rejeski (CLIP) 2011, Uusitupa 1993] and also others who provided information, but their trials were later found not to fulfil our inclusion criteria. Funding: The Health Services Research Unit is funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorate.Peer reviewedPublisher PD
Local Cortical Tension by Myosin II Guides 3D Endothelial Cell Branching
SummaryA key feature of angiogenesis is directional control of endothelial cell (EC) morphogenesis and movement [1]. During angiogenic sprouting, endothelial âtip cellsâ directionally branch from existing vessels in response to biochemical cues such as VEGF or hypoxia and migrate and invade the surrounding extracellular matrix (ECM) in a process that requires ECM remodeling by matrix metalloproteases (MMPs) [2â4]. Tip EC branching is mediated by directional protrusion of subcellular pseudopodial branches [5, 6]. Here, we seek to understand how EC pseudopodial branching is locally regulated to directionally guide angiogenesis. We develop an in vitro 3D EC model system in which migrating ECs display branched pseudopodia morphodynamics similar to those in living zebrafish. Using this system, we find that ECM stiffness and ROCK-mediated myosin II activity inhibit EC pseudopodial branch initiation. Myosin II is dynamically localized to the EC cortex and is partially released under conditions that promote branching. Local depletion of cortical myosin II precedes branch initiation, and initiation can be induced by local inhibition of myosin II activity. Thus, local downregulation of myosin II cortical contraction allows pseudopodium initiation to mediate EC branching and hence guide directional migration and angiogenesis
Generalised Compositional Theories and Diagrammatic Reasoning
This chapter provides an introduction to the use of diagrammatic language, or
perhaps more accurately, diagrammatic calculus, in quantum information and
quantum foundations. We illustrate the use of diagrammatic calculus in one
particular case, namely the study of complementarity and non-locality, two
fundamental concepts of quantum theory whose relationship we explore in later
part of this chapter.
The diagrammatic calculus that we are concerned with here is not merely an
illustrative tool, but it has both (i) a conceptual physical backbone, which
allows it to act as a foundation for diverse physical theories, and (ii) a
genuine mathematical underpinning, permitting one to relate it to standard
mathematical structures.Comment: To appear as a Springer book chapter chapter, edited by G.
Chirabella, R. Spekken
Interpreting BOLD: towards a dialogue between cognitive and cellular neuroscience
Cognitive neuroscience depends on the use of blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to probe brain function. Although commonly used as a surrogate measure of neuronal activity, BOLD signals actually reflect changes in brain blood oxygenation. Understanding the mechanisms linking neuronal activity to vascular perfusion is, therefore, critical in interpreting BOLD. Advances in cellular neuroscience demonstrating differences in this neurovascular relationship in different brain regions, conditions or pathologies are often not accounted for when interpreting BOLD. Meanwhile, within cognitive neuroscience, increasing use of high magnetic field strengths and the development of model-based tasks and analyses have broadened the capability of BOLD signals to inform us about the underlying neuronal activity, but these methods are less well understood by cellular neuroscientists. In 2016, a Royal Society Theo Murphy Meeting brought scientists from the two communities together to discuss these issues. Here we consolidate the main conclusions arising from that meeting. We discuss areas of consensus about what BOLD fMRI can tell us about underlying neuronal activity, and how advanced modelling techniques have improved our ability to use and interpret BOLD. We also highlight areas of controversy in understanding BOLD and suggest research directions required to resolve these issues
Vascular responses of the extremities to transdermal application of vasoactive agents in Caucasian and African descent individuals
This is an accepted manuscript of an article published by Springer in European Journal of Applied Physiology on 04/04/2015, available online: https://doi.org/10.1007/s00421-015-3164-2
The accepted version of the publication may differ from the final published version.© 2015, Springer-Verlag Berlin Heidelberg. Purpose: Individuals of African descent (AFD) are more susceptible to non-freezing cold injury than Caucasians (CAU) which may be due, in part, to differences in the control of skin blood flow. We investigated the skin blood flow responses to transdermal application of vasoactive agents. Methods: Twenty-four young males (12 CAU and 12 AFD) undertook three tests in which iontophoresis was used to apply acetylcholine (ACh 1 w/v %), sodium nitroprusside (SNP 0.01 w/v %) and noradrenaline (NA 0.5 mM) to the skin. The skin sites tested were: volar forearm, non-glabrous finger and toe, and glabrous finger (pad) and toe (pad). Results: In response to SNP on the forearm, AFD had less vasodilatation for a given current application than CAU (P = 0.027â0.004). ACh evoked less vasodilatation in AFD for a given application current in the non-glabrous finger and toe compared with CAU (P = 0.043â0.014) with a lower maximum vasodilatation in the non-glabrous finger (median [interquartile], AFD n = 11, 41[234] %, CAU n = 12, 351[451] %, P = 0.011) and non-glabrous toe (median [interquartile], AFD n = 9, 116[318] %, CAU n = 12, 484[720] %, P = 0.018). ACh and SNP did not elicit vasodilatation in the glabrous skin sites of either group. There were no ethnic differences in response to NA. Conclusion: AFD have an attenuated endothelium-dependent vasodilatation in non-glabrous sites of the fingers and toes compared with CAU. This may contribute to lower skin temperature following cold exposure and the increased risk of cold injuries experienced by AFD.Published versio
An approach for assessing and ranking fisheries management scenarios in spatially delimited marine areas
Spatial restrictions to human activities such as bottom trawling are increasingly used to improve the ecological condition of disturbed habitats. Such management interventions typically have socio-economic consequences, which creates a challenge for those making decisions about which activities should be restricted and where restrictions should apply. We present an approach for predicting the effects of fisheries management scenarios in spatially delimited marine areas and ranking themâusing a loss functionâaccording to how well they achieve desired outcomes across a set of ecological and socio-economic indicators. This approach is demonstrated by simulating alternative fishing gear restrictions and zoning options within a hypothetical marine protected area (MPA). Relative benthic status (RBS; an indicator of ecological condition) and relative catch value (RCV; an indicator of potential economic cost) were estimated for the baseline environment and 21 potential management scenarios. The rank order depended on which indicator was prioritized (i.e. whether RBS or RCV was given greater weighting in the loss function), with the top-ranked scenarios in each case involving considerably different management measures. The methods presented can be applied anywhere using locally or strategically relevant indicators to help identify spatial fisheries management measures that minimize ecological and socio-economic trade-offs
Diagenetic priming of submarine landslides in ooze-rich substrates
Oozes are the most widespread deep-sea sediment in the global ocean, but very little is known about how changes in their physical properties during burial impact slope stability and related geohazards. We used three-dimensional seismic reflection, geochemical, and petrophysical data acquired both within and adjacent to 13 large (in total ~6330 km2) submarine slides on the Exmouth Plateau, North West Shelf, Australia, to investigate how the pre-slide physical properties of oozes control slope failure and emplacement processes. Our integrated data set allows potential slide surfaces to be detected within ooze successions, a crucial advance for improved submarine geohazard assessment. Moreover, we demonstrate that the interplay of tectonics, ocean current activity, and silica diagenesis can prime multiple slides on very low-gradient slopes in tropical oceanic basins. Therefore, the diagenetic state of silica-rich sediments should be considered in future studies to improve slope stability assessments
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