980 resultados para Agropecuarian producers


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Some 30 years ago, Australia introduced the Children's Television Standards (CTS) with the twin goals of providing children with high-quality local programs and offering some protection from the perceived harms of television. The most recent review of the CTS occurred in the context of a decade of increasing international concern at rising levels of overweight and obesity, especially in very young children. Overlapping regulatory jurisdictions and co-regulatory frameworks complicate the process of addressing pressing issues of child health, while rapid changes to the media ecology have both extended the amount of programming for children and increased the economic challenges for producers. Our article begins with an overview of the conceptual shifts in priorities articulated in the CTS over time. Using the 2007-09 Review of the CTS as a case study, it then examines the role of research and stakeholder discourses in the CTS review process and critiques the effectiveness of existing regulatory regimes, both in providing access to dedicated children's content and in addressing the problem of escalating obesity levels in the population.

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This paper identifies a number of strategies employed by policy actors in the production of Australian higher education entry policy during the period 1987 to 1996, with a particular focus on the production of Queensland higher education entry policy text in 1990 (Viviani, 1990, The Review of Tertiary Entrance in Queensland, 1990 , Department of Education, Queensland). The paper begins from the premise that while policy is often intended to be read as if spoken with a single voice, suggesting rational debate and (then) consensus among policy producers, it is more cogently understood as the product of struggle and conflict. Informed by 27 semi-structured interviews with politicians, political advisers, bureaucrats, academics, institutional administrators and independent authorities, the paper addresses the temporary settling of these actors' struggles and conflicts in contexts of policy making through strategies of negotiation. Rather than providing a sequential account of higher education policy that weaves its way through these negotiations, as grand narrative, the paper is more sporadic in its representations of strategies, identifying them in 'local' and specific knowledges and practices. Drawing on Foucault, what emerges is both an archaeology and genealogy of policy production (Gale, 2001, Journal of Education Policy , 16(5), pp. 379-393).

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Extending knowledge of the cultural shaping and variegating of white identity that occurs through the commercial diffusion of identity myths, we examine the reception of Southern identity myths promoted in the oppositional narratives of New South commercial media. We characterize oppositional narratives as texts which operate by eliciting an interpretive reading that devalues rather than supports the surface narrative, and explain the duplicitous text as one intended to seduce a dominant power, while empowering and bolstering identity of a marginalized group. After elaborating how oppositional discourse can serve to reinforce the identity frame constructed by regional media producers, we report on a study examining how urban and rural Southerners read and respond to this discourse. Our findings highlight mediators in the relationship between individuals’ oppositional readings and their alignment of identity in a manner responsive to it.

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Movie directors and producers worldwide, in their quest to narrate a good story that warrants repeated audience viewing, use many cinematic elements to intensify and clarify the viewing experience. One such element that directors manipulate is lighting. In this paper we examine one aspect of lighting, namely flashing lights, and its role as an intensifier of dramatic effects in film. We present an algorithm for robust extraction of flashing lights and a simple mechanism to group detected flashing lights into flashing light scenes and analyze the role of these segments in story narration. In addition, we demonstrate how flashing lights detection can improve the performance of shot-based video segmentation. Experiments on a number of video sequences extracted from real movies yields good results. Our technique detects 90.4% of flashing lights. The detected flashing lights correctly eliminates 92.7% of false cuts in these sequences. In addition, data support is compiled to demonstrate the association between flashing light scenes and certain dramatic intensification events such as supernatural power, crisis or excitement.

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Objective and subjective evaluations of goats for meat production are related to important determinants of production and profitability. The most important attributes in assessment of goats for market are: live weight; body condition score; and the age of goats. As goats grow, their carcass and body organs increase in weight in proportion to the empty body weight. For farmers and field workers the linear regression approach for estimating carcass weight by measuring live weight is the most suitable as it accounts for 88 to 97% of the variation in carcass, offal and boneless meat weight. Live weight scales or heart girth tapes should be used and the risks and errors associated with these methods are summarized. The proportion of a live goat that is the carcass, known as dressing percentage, increases from 35% to about 50% as goats grow. The usefulness and errors associated with dressing percentage in field estimation are discussed. A valuable subjective method for estimating the nutritional status of goats is the use of body condition scoring as it accounts for 60 to 67% of the variation in live weight change, carcass weight and fat reserves of goats. A method for body condition scoring and a similar fat scoring system are explained. Body condition score is also associated with mortality risk and reproductive performance of goats. The number of permanent incisors in the lower jaw of goats is a method of estimating the age of goats but is biased by differences in live weights of goats. The value and role of ultrasound scanning the carcasses of goats is summarized. For the marketing of kid meat no permanent incisors should have erupted. Other useful practices for the successful marketing of goat meat are discussed including: knowing market specifications and chemical withholding periods; animal health; prevention of bruising; identification of goats; size of consignments; timeliness; provision of paperwork. A checklist is provided. The use of subjective and objective assessment techniques in evaluating goats for meat production will provide the best results. Where only subjective assessment techniques are available they will provide satisfactory performance provided the skills have been learnt and are applied.

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Classical resource- and the less studied ratio-dependent models of predator–prey relationships provide divergent predictions as to the sustained ecological effects of bottom-up forcing. While resource-dependent models, which consider only instantaneous prey density in modelling predator responses, predict community responses that are dependent on the number of trophic levels in a system, ratio-dependent models, which consider the number of prey per consumer, predict proportional increase in each level irrespective of chain length. The two models are only subtly different for systems with two or three trophic levels but in the case of four trophic levels, predict opposite effects of enrichment on primary producers. Despite the poor discriminatory power of tests of the models in systems with two or three trophic levels, field tests in estuarine and marine systems with four trophic levels have been notably absent. Sampling of phytoplankton, macroinvertebrates, invertebrate-feeding fishes, piscivorous fishes in Kooloonbung Creek, Hastings River estuary, eastern Australia, subject to over 20 years of sewage discharge, revealed increased abundances in all four trophic levels at the disturbed location relative to control sites. Increased abundance of phytoplankton at the disturbed site was counter to the predictions of resource-dependent models, which posit a reduction in the first trophic level in response to enrichment. By contrast, the increase in abundance of this first trophic level and the proportionality of increases in abundances of each of the four trophic groups to nitrogen loading provided strong support for ratio dependency. This first evidence of ratio dependence in an estuarine system with four trophic levels not only demonstrates the applicability of ecological theory which seeks to simplify the complexity of systems, but has implications for management. Although large nutrient inputs frequently induce mortality of invertebrates and fish, we have shown that smaller inputs may in fact enhance biomass of all trophic levels.

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Electrospun polyelectrolyte hydrogel nanofibres are being developed for many applications including artificial muscles, scaffolds for tissue engineering, wound dressings and controlled drug release. For electrospun polyelectrolytes, a post-spinning crosslinking process is necessary for producing a hydrogel. Typically, radiation or thermal crosslinking routines are employed that require multifunctional crosslinking molecules and crosslink reaction initiators (free radical producers). Here, ultraviolet subtype-C (UVC) radiation was employed to crosslink neat poly(acrylic acid) (PAA) nanofibres and films to different crosslink densities. Specific crosslink initiators or crosslinking molecules are not necessary in this fast and simple process providing an advantage for biological applications. Scanning probe microscopy was used for the first time to measure the dry and wet dimensions of hydrogel nanofibres. The diameters of the swollen fibres decrease monotonically with increasing UVC radiation time. The fibres could be reversibly swollen/contracted by treatment with solutions of varying pH, demonstrating their potential as artificial muscles. The surprising success of UVC radiation exposure to achieve chemical crosslinks without a specific initiator molecule exploits the ultrathin dimensions of the PAA samples and will not work with relatively thick samples.

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The emergence of synthetic bovine Somatotropin (bST) is one of the most widely discussed advances in biotechnology. Its potential impacts on milk production around the world could be significant. However, the exact economic impacts of bST in any one region depends on a number of factors, some of which are still highly controversial.

This article sets out to estimate the economic impacts of the adoption of bST in the United States, the single largest milk producer in the Western world. A quarterly econometric model of the U.S. dairy sector is used to forecast the total production, consumption, and excess supply of milk to 1995. The preliminary results indicate that under the assumption of a gradual rate of adoption and a 15 percent milk production response, the United States could be exporting as much milk as New Zealand by 1995. Should the production response rate or the adoption rate be higher, the United States could indeed become a major competitor in the world dairy market by 1995.

Although such a development could adversely impact on other dairy exporters, such as New Zealand, the precise economic impacts on world prices and trade would depend crucially on the position that other major dairy producers, especially the EC, adopt with respect to the use of bST.

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Indian firms are major global producers of relatively affordable generic medicines. Access to such drugs makes the difference between life and death for billions of people in the Global South. The Economist noted recently that ‘America should not use trade deals to swaddle drugmakers in excessive patent protections’. Nor should the European Union (EU) impose obstacles to the supply of generic drugs by Indian firms beyond those already mandated by the Trade Related Aspects of Intellectual Property Rights (TRIPS) Agreement. Free trade negotiations between the EU (reported to be close to completion) constitute a clear threat to the role of India as the ‘pharmacy of the developing world’.

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There are many challenges ahead for producers, consumers and regulators of Australian media. Perhaps the biggest challenge is to understand that, along with new media, we now have a new media audience - an increasingly different social formation, often eluding efforts to contain its actions within profitable corporate pathways.

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Little is known on the degree to which terrestrial organic matter delivered to tropical estuaries contributes to estuarine consumers. Here, stable isotope analysis is used to constrain this contribution for contrasting east African estuaries whose catchments differ in relative C3/C4 vegetation cover. As these two types of vegetation differ strongly in δ13C, we anticipated that terrestrial subsidies would be reflected in a gradient in estuarine consumer δ13C values, following the relative importance of C3 (characterised by low δ13C) vs. C4 (characterised by high δ13C) cover. Five estuaries were sampled for aquatic biogeochemical parameters, primary producers and consumers of different trophic ecologies: the Zambezi (catchment with a C3/C4 cover of 61/39%) in Mozambique, the Tana in Kenya (36/64%) and the Betsiboka (42/58%), Rianila (85/15%) and Canal des Pangalanes (C3-dominated) in Madagascar. Sampling was done before and after the 2010/2011 wet season. There were positive relationships between the proportion of C4 cover in the catchment and turbidity, δ13CDIC, δ13CDOC, δ13CPOC and δ15NPN. There were also significant positive relationships between δ13CPOC and consumer δ13C and between δ15NPN and consumer δ15N for all consumer trophic guilds, confirming the incorporation of organic material transported from the catchments by estuarine consumers, and implying that this material is transported up to high trophic level fish. Bayesian mixing models confirmed that C4 material was the most important source for the highly turbid, C4-dominated estuaries, contributing up to 61–91% (95% CI) to phytodetritivorous fish in the Betsiboka, whereas for the less turbid C3-dominated estuaries terrestrial subsidies were not as important and consumers relied on a combination of terrestrial and aquatic sources. This shows that the ecology of the overall catchment affects the estuaries at the most basic, energetic level, and activities that alter the turbidity and productivity of rivers and estuaries can affect food webs well beyond the area of impact.

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Mandatory food fortification “occurs when governments legally oblige food producers to fortify particular foods or categories of foods with specified micronutrients” [1]. Because mandatory food fortification exposes everyone in the population who consumes the fortified food(s) to raised levels of the specified micronutrient, it is one of the most powerful policy instruments available to influence dietary intake and population health outcomes. Many national food regulatory authorities have established policy guidance on mandatory food fortification. From an international perspective, the Codex Alimentarius Commission (Codex) provides principles for the addition of essential nutrients to foods [2]. According to these Codex principles, mandatory food fortification with additional vitamins and minerals is recommended where there is proven public health and nutrition need (Note: these principles are under review at the time of writing).

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In spite of all the debates and controversies, a global consensus has been reached that climate change is a reality and that it will impact, in diverse manifestations that may include increased global temperature, sea level rise, more frequent occurrence of extreme weather events, change in weather patterns, etc., on food production systems, global biodiversity and overall human well being. Aquaculture is no exception. The sector is characterized by the fact that the organisms cultured, the most diverse of all farming systems and in the number of taxa farmed, are all poikilotherms. It occurs in fresh, brackish and marine waters, and in all climatic regimes from temperate to tropical. Consequently, there are bound to be many direct impacts on aquatic farming systems brought about by climate change. The situation is further exacerbated by the fact that certain aquaculture systems are dependent, to varying degrees, on products such as fishmeal and fish oil, which are derived from wild-caught resources that are subjected to reduction processes. All of the above factors will impact on aquaculture in the decades to come and accordingly, the aquatic farming systems will begin to encounter new challenges to maintain sustainability and continue to contribute to the human food basket. The challenges will vary significantly between climatic regimes. In the tropics, the main challenges will be to those farming activities that occur in deltaic regions, which also happen to be hubs of aquaculture activity, such as in the Mekong and Red River deltas in Viet Nam and the Ganges-Brahamaputra Delta in Bangladesh. Aquaculture in tropical deltaic areas will be mostly impacted by sea level rise, and hence increased saline water intrusion and reduced water flows, among others. Elsewhere in the tropics, inland cage culture and other aquaculture activities could be impacted by extreme weather conditions, increased upwelling of deoxygenated waters in reservoirs, etc., requiring greater vigilance and monitoring, and even perhaps readiness to move operations to more conducive areas in a waterbody. Indirect impacts of climate change on tropical aquaculture could be manifold but are perhaps largely unknown. The reproductive cycles of a great majority of tropical species are dependent on monsoonal rain patterns, which are predicted to change. Consequently, irrespective of whether cultured species are artificially propagated or not, changes in reproductive cycles will impact on seed production and thereby the whole grow-out cycle and modus operandi of farm activities. Equally, such impacts will be felt on the culture of those species that are based on natural spat collection, such as that of many cultured molluscs. In the temperate region, global warming could raise temperatures to the upper tolerance limits of some cultured species, thereby making such culture systems vulnerable to high temperatures. New or hitherto non-pathogenic organisms may become virulent with increases in water temperature, confronting the sector with new, hitherto unmanifested and/or little known diseases. One of the most important indirect effects of climate change will be driven by impacts on production of those fish species that are used for reduction, and which in turn form the basis for aquaculture feeds, particularly for carnivorous species. These indirect effects are likely to have a major impact on some key aquaculture practices in all climatic regimes. Limitations of supplies of fishmeal and fish oil and resulting exorbitant price hikes of these commodities will lead to more innovative and pragmatic solutions on ingredient substitution for aquatic feeds, which perhaps will be a positive result arising from a dire need to sustain a major sector. Aquaculture has to be proactive and start addressing the need for adaptive and mitigative measures. Such measures will entail both technological and socio-economic approaches. The latter will be more applicable to small-scale farmers, who happen to be the great bulk of producers in developing countries, which in turn constitute the “backbone’ of global aquaculture. The sociological approaches will entail the challenge of addressing the potential climate change impacts on small farming communities in the most vulnerable areas, such as in deltaic regions, weighing the most feasible adaptive options and bringing about the policy changes required to implement these adaptive measures economically and effectively. Global food habits have changed over the years. We are currently in an era where food safety and quality, backed up by ecolabelling, are paramount; it was not so 20 years ago. In the foreseeable future, we will move into an era where consumer consciousness will demand that farmed foods of every form will have to include in their labeled products the green house gas (GHG) emissions per unit of produce. Clearly, aquaculture offers an opportunity to meet these aspirations. Considering that about 70 percent of all finfish and almost 100 percent of all molluscs and seaweeds are minimally GHG emitting, it is possible to drive aquaculture as the most GHG-friendly food source. The sector could conform to such demands and continue to meet the need for an increasing global food fish supply. However, to achieve this, a paradigm shift in our seafood consumption preferences will be needed.

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Marine diatoms and dinoflagellates play a variety of key ecosystem roles as important primary producers (diatoms and some dinoflagellates) and grazers (some dinoflagellates). Additionally some are harmful algal bloom (HAB) species and there is widespread concern that HAB species may be increasing accompanied by major negative socio-economic impacts, including threats to human health and marine harvesting1, 2. Using 92,263 samples from the Continuous Plankton Recorder survey, we generated a 50-year (1960–2009) time series of diatom and dinoflagellate occurrence in the northeast Atlantic and North Sea. Dinoflagellates, including both HAB taxa (for example, Prorocentrum spp.) and non-HAB taxa (for example, Ceratium furca), have declined in abundance, particularly since 2006. In contrast, diatom abundance has not shown this decline with some common diatoms, including both HAB (for example, Pseudo-nitzschia spp.) and non-HAB (for example, Thalassiosira spp.) taxa, increasing in abundance. Overall these changes have led to a marked increase in the relative abundance of diatoms versus dinoflagellates. Our analyses, including Granger tests to identify criteria of causality, indicate that this switch is driven by an interaction effect of both increasing sea surface temperatures combined with increasingly windy conditions in summer.

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1.Quantitative tools to describe biological communities are important for conservation and ecological management. The analysis of trophic structure can be used to quantitatively describe communities. Stable isotope analysis is useful to describe trophic organization, but statistical models that allow the identification of general patterns and comparisons between systems/sampling periods have only recently been developed. 2.Here, stable isotope-based Bayesian community-wide metrics are used to investigate patterns in trophic structure in five estuaries that differ in size, sediment yield and catchment vegetation cover (C3/C4): the Zambezi in Mozambique, the Tana in Kenya and the Rianila, the Betsiboka and Pangalanes Canal (sampled at Ambila) in Madagascar. 3.Primary producers, invertebrates and fish of different trophic ecologies were sampled at each estuary before and after the 2010–2011 wet season. Trophic length, estimated based on δ15N, varied between 3·6 (Ambila) and 4·7 levels (Zambezi) and did not vary seasonally for any estuary. Trophic structure differed the most at Ambila, where trophic diversity and trophic redundancy were lower than at the other estuaries. Among the four open estuaries, the Betsiboka and Tana (C4-dominated) had lower trophic diversity than the Zambezi and Rianila (C3-dominated), probably due to the high loads of suspended sediment, which limited the availability of aquatic sources. 4.There was seasonality in trophic structure at Ambila and Betsiboka, as trophic diversity increased and trophic redundancy decreased from the prewet to the postwet season. For Ambila, this probably resulted from the higher variability and availability of sources after the wet season, which allowed diets to diversify. For the Betsiboka, where aquatic productivity is low, this was likely due to a greater input of terrestrial material during the wet season. 5.The comparative analysis of community-wide metrics was useful to detect patterns in trophic structure and identify differences/similarities in trophic organization related to environmental conditions. However, more widespread application of these approaches across different faunal communities in contrasting ecosystems is required to allow identification of robust large-scale patterns in trophic structure. The approach used here may also find application in comparing food web organization before and after impacts or monitoring ecological recovery after rehabilitation.