958 resultados para Massachusetts Agricultural Repository and Journal.


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Signed on p.24: John Hare Powel.

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Mode of access: Internet.

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A review is presented of the interrelationships between arthropod vectors, the diseases they transmit and agricultural development. Particular attention is given to the effects of deforestation, livestock development and irrigation on the abundance of vectors and changing patterns of diseases such as malaria, trypanosomiases, leishmaniasis, Chagas' and some arboviral infections. The question as whether keeping livestock diverts biting away from people and reduces diseases such as malaria - that is zooprophylaxis, or whether the presence of cattle actually increases biting populations is discussed.

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The use of fertilizers and solid amendments in agriculture generates special interest for their effect on crop productivity, as well as for their environmental impact. The efficient use of these products demands knowing their physical and mechanical properties, the storing conditions effect and the operational characteristics of the metering systems used in the fertilizing equipment. In this context, the present study was developed with the purpose of evaluating the operational characteristics of different fertilizing metering systems and to determine the adequate metering system-product operational parameters, using powder lime, powder gypsum, granular 10-30-10 (N-P-K), and granular urea. Operational differences were established among four types of commercial fertilizer metering systems, including wire auger, star-shaped feed wheel, feed screw and ridged traction wheel. The study found that the unloading rate depends directly on the fertilizer metering system's rotating speed and is affected by particle size, repose angle, bulk density and moisture content of the applied product. The wire auger and star-shaped feed wheel metering systems were adequate for the distribution of powder products and the feed screw for granulated fertilizers. Furthermore, theoretical and experimental characteristic equations were established, defining curves for calibration and handling of the products plus the rotating speed range in which a better distributing behavior was achieved.

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ABSTRACT This study aims at presenting the process of machine design and agricultural implements by means of a reference model, formulated with the purpose of explaining the development activities of new products, serving as a guideline to coach human resources and to assist in formalizing the process in small and medium-sized businesses (SMB), i.e. up to 500 employees. The methodology used included the process modeling, carried out from case studies in the SMB, and the study of reference models in literature. The modeling formalism used was based on the IDEF0 standard, which identifies the dimensions required for the model detailing: input information; activities; tasks; knowledge domains; mechanisms; controls and information produced. These dimensions were organized in spreadsheets and graphs. As a result, a reference model with 27 activities and 71 tasks was obtained, distributed over four phases of the design process. The evaluation of the model was carried out by the companies participating in the case studies and by experts, who concluded that the model explains the actions needed to develop new products in SMB.

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Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

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The recent discovery of the monumental 5000 years old tower tombs on top of the up to 1850 m high Shir plateau has raised numerous questions about the economic and infrastructural basis of the agro-pastoral-piscicultural society which likely has constructed them. The scattered oasis settlement of Maqta, situated just below the towers in a rugged desert environment has therefore been studied from 2001 to 2003 to understand its prehistoric and present role along the ancient trade route which connected the inner-Omani Sharqiya across the southern Hajar mountains with the ocean port of Tiwi. Maqta consists of a central area with 59 buildings and 12 scattered temporary settlements comprising a total of about 200 semi-nomadic inhabitants and next to 900 sheep and goats. The 22 small springs with a flow rate between 5 and 1212-l h^-1 are watering 16 terrace systems totaling 4.5 ha of which 2.9 ha are planted to date palms (Phoenix dactylifera L.), 0.4 ha to wheat landraces (Triticum durum and Triticum aestivum) during the cooler winter months, 0.4 are left fallow and 0.8 h are abandoned. During a pronounced drought period from 2001 to 2003, the springs’ flow rate declined between 38% and 72%. Most of the recent buildings of the central housing area were found empty or used as temporary stores by the agro-pastoral population watching their flocks on the surrounding dry mountains. There is no indication that there ever was a settlement older than the present one. A number of Hafit (3100–2700 BC) and Umm an-Nar (2700–2000 BC) tombs just above the central housing area and further along one of the trade routes to the coast are the only indication of an old pastoral landuse in Maqta territory where oasis agriculture may have entered only well after 1000 AD. With this little evidence of existence during the 3rd millennium BC, Maqta is unlikely to have played any major role favouring the construction of the nearby monumental Shir tower tombs other than providing water for herders and their flocks, early migrant traders or tower tomb constructors.

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Brazil has been increasing its importance in agricultural markets. The reasons are well known to be the relative abundance of land, the increasing technology used in crops, and the development of the agribusiness sector which allow for a fast response to price stimuli. The elasticity of acreage response to increases in expected return is estimated for Soybeans in a dynamic (long term) error correction model. Regarding yield patterns, a large variation in the yearly rates of growth in yield is observed, climate being probably the main source of this variation which result in ‘good’ and ‘bad’ years. In South America, special attention should be given to the El Niño and La Niña phenomena, both said to have important effects on rainfalls patterns and consequently in yield. The influence on El Niño and La Niña in historical data is examined and some ways of estimating the impact of climate on yield of Soybean and Corn markets are proposed. Possible implications of climate change may apply.

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Agriculture in the Mojanda Watershed is facing rainfall reductions caused by climate change. Reductions of water availability in the Watershed are also due to constant extension of the agricultural activities into the páramo ecosystem above 3000m a.s.l., with this ecosystem having immanently important functions in the local water balance. The application of pesticides threatens the quality of water and with less precipitation contaminations will further concentrate in the outflow. To analyze problems associated with agricultural practices in the area a questionnaire about agricultural practices (28) was conducted and fields (20) were surveyed for pests and diseases with a focus on potatoes (Solanum tuberosum L.), tree tomatoes (Solanum betaceum Cav.) and peas (Pisum sativum L.). Potatoes were infected to a low degree with Phytophthora infestans and according to the farmers the Andean potato weevil (Premnotrypes spec.) caused biggest losses. To combat the weevil the soils are disinfected with toxic Carbofuran (WHO Class 1B). Tree tomatoes showed symptoms of various fungal diseases. Most important was Fusarium solani causing the branches to rot and Anthracnosis (Colletotrichum gloeosporioides) causing the fruits to rot. Fungicide applications were correspondingly high. Peas were only minorly affected by Ascochyta blight (Mycosphaerella pinodes) and a root rot. Overall 19 active ingredients were applied of which fungicide Mancozeb (WHO class table 5) and insecticide Carbofuran (WHO Class 1B) were applied the most. Approved IPM methods are advised to reduce pesticide use. For tree tomatoes regular cutting of branches infected with F. solani and regular collection and disposal of infected fruits with Anthracnosis are advised. For potatoes plastic barriers around the fields prevent the Andean potato weevil from laying eggs thus reducing infestation with the larvae in the tubers. Local bioinsecticide “Biol” seems effective and without harm to the environment, although not used by many farmers. Organic fertilization promises to restore decreasing soil fertility, water holding capacity and reduce erosion. The here presented alternatives and strategies to reduce pesticide use pose an opportunity to preserve the water resources of the region.

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In this chapter we provide a summary description of Colombian Competition Policy with an emphasis on the agricultural sector. Key developments and recent changes in institutional arrangements affecting competition policy, as it applies to the agricultural sector, are highlighted. Illustrative case studies are depicted to show the richness and complexity of policy developments and enforcement. Some general conclusions are drawn from this examination.

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This article demonstrates that the design and nature of agricultural support schemes has an influence on farmers' perception of their level of dependence on agricultural support. While direct aid payments inform farmers about the extent to which they are subsidised, indirect support mechanisms veil the level of subsidisation, and therefore they are not fully aware of the extent to which they are supported. To test this hypothesis, we applied data from a survey of 4,500 farmers in three countries: the United Kingdom, Germany and Portugal. It is demonstrated that indirect support, such as that provided through artificially high consumer prices, gives an illusion of free and competitive markets among farmers. This 'visibility' hypothesis is evaluated against an alternative hypothesis that assumes farmers have complete, or at least a fairly comprehensive level of, information on agricultural support schemes. Our findings show that this alternative hypothesis can be ruled out.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)