979 resultados para Virginia Agricultural, Mechanical, and Tobacco Exposition (1888 : Richmond, Va.)
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AIM To systematically assess the efficacy of patient-administered mechanical and/or chemical plaque control protocols in the management of peri-implant mucositis (PM). MATERIAL AND METHODS Randomized (RCTs) and Controlled Clinical Trials (CCTs) were identified through an electronic search of three databases complemented by manual search. Identification, screening, eligibility and inclusion of studies was performed independently by two reviewers. Studies without professional intervention or with only mechanical debridement professionally administered were included. Quality assessment was performed by means of the Cochrane Collaboration's tool for assessing risk of bias. RESULTS Eleven RCTs with a follow-up from 3 to 24 months were included. Definition of PM was lacking or heterogeneously reported. Complete resolution of PM was not achieved in any study. One study reported 38% of patients with complete resolution of PM. Surrogate end-point outcomes of PM therapy were often reported. The choice of control interventions showed great variability. The efficacy of powered toothbrushes, a triclosan-containing toothpaste and adjunctive antiseptics remains to be established. High quality of methods and reporting was found in four studies. CONCLUSIONS Professionally- and patient-administered mechanical plaque control alone should be considered the standard of care in the management of PM. Therapy of PM is a prerequisite for the prevention of peri-implantitis.
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This paper reviews the development of the agricultural sector in Myanmar after the transition to an open economy in 1988 and analyzes the nature as well as the performance of the agricultural sector. The avoidance of social unrest and the maintenance of control by the regime are identified as the two key factors that have determined the nature of agricultural policy after 1988. A major consequence of agricultural policy has been a clear difference in development paths among the major crops. Production of crops that had a potential for development showed sluggish growth due to policy constraints, whereas there has been a self-sustaining increase in the output of those crops that have fallen outside the remit of agricultural policy.
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Abstract: By means of a GTAP based-CGE model, we investigate the impact of the elimination of import tariffs and non-tariff policy barriers (NTPBs) on agricultural trade towards East Asian FTAs. To do that, we first measure the NTPBs by employing a widely-used method derived from the literature on border effects. Next, by adding into the GTAP database our estimates on the NTPBs, which the original GTAP database by its nature does not succeed in incorporating, we compute the impact of the entire elimination of policy barriers (the complete reduction of import tariffs and of NTPBs) on GDP.
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Forest connectivity restoration is a major goal in natural resource planning. Given the high amount of abandoned cultivated lands, setting efficient methods for the reforestation of agricultural lands offers a good opportunity to face this issue. However, reforestations must be carefully planned, which poses two main challenges. In first place, to determine those agricultural lands that, once reforested, would meet more effectively the planning goals. As a further step, in order to grant the success of the activity, it is fairly advisable to select those tree species that are more adapted to each particular environment. Here we intend to give response to both requirements by proposing a sequential and integrated methodology that has been implemented in two Spanish forest districts, which are formed by several landscape types that were previously defined and characterized. Using the software Conefor Sensinode, a powerful tool for quantifying habitat availability that is based on graph theory concepts, we determined the landscapes where forest planning should have connectivity as a major concern and, afterwards, we detected the agricultural patches that would contribute most to enhance connectivity if they were reforested. The subsequent reforestation species assessment was performed within these priority patches. Using penalized logistic regressions we fitted ecological niche models for the Spanish native tree species. The models were trained with species distribution data from the Spanish Forest Map and used climatic and lithological variables as predictors. Model predictions were used to build ordered lists of suitable species for each priority patch. The lists include dominant and non dominant tree species and allow adding biodiversity goals to the reforestation planning. The result of this combined methodology is a map of agricultural patches that would contribute most to uphold forest connectivity if they were reforested and a list of suitable tree species for each patch ordered by occurrence probability. Therefore the proposed methodology may be useful for suitable and efficient forest planning and landscape designing.
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Environmentally friendly molybdenum disulfide (INT-MoS2) inorganic nanotubes were introduced into an isotactic polypropylene (iPP) polymer matrix to generate novel nanocomposite materials through an advantageous melt-processing route. The effects of INT-MoS2 content on the thermal, mechanical and tribological properties were investigated. The incorporation of INT-MoS2 generates notable performance enhancements through reinforcement effects, highly efficient nucleation activity and excellent lubricating ability in comparison with other nanoparticle fillers such as nanoclays, carbon nanotubes, silicon nitrides and halloysite nanotubes. It was shown that these INT-MoS2 nanocomposites can provide an effective balance between performance, cost effectiveness and processability, and should be of some interest in the area of multifunctional polymer nanocomposite materials.
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Outline: • Introduction • Process Experimental Setup • Experimental Procedure • Experimental Results for Al2024-T351 and Ti6Al4V - Residual stresses - Tensile Strength - Fatigue Life • Discussion and Outlook - Prospects for technological applications of LSP
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The Renewable Energy Directive (2009/28/EC) requires that 20% of the EU's energy needs should come from renewable sources by 2020, and includes a target for the transport sector of 10% from biofuels. This report analyses and discusses the global impacts of this biofuel target on agricultural production, markets and land use, as simulated by three agricultural sector models, AGLINK-COSIMO, ESIM and CAPRI. The impacts identified include higher EU production of ethanol and biodiesel, and of the crops used to produce them, as well as more imports of both biofuels. Trade flows of biofuel feedstocks also change to reflect greater EU demand, including a significant increase in vegetable oil imports. However, as the extra demand is small in world market terms, the impact on world market prices is limited. With the EU biofuel target, global use of land for crop cultivation is higher by 5.2 million hectares. About one quarter is area within the EU, some of which would otherwise have left agriculture.
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This study evaluated the effect of adding soy protein isolate (SPI) and long-chain perception, trained and untrained panel inulin (INL) blends with 10 different SPI : INL ratios on the textural, rheological and 17 microstructural properties of freshly made and frozen/thawed potato puree. All the potato puree samples were subjected to a sensory texture pro?le analysis and a 21 trained panel rated the intensity of six descriptors, while an untrained panel did the same on six selected frozen/thawed products. The main SPI : INL ratio effect remained signi?cant for all the descriptors evaluated, when the analysis of variance was applied considering the untrained assessors as random effects. However, only trained panel scores for creaminess corresponded well with untrained assessor. Rheological ?ow index values were linked with variations in perceived consistency, and geometric and surface textural attributes were explained by structural features such as the presence of INL crystallites and SPI coarse strands.
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Nitrate leaching (NL) is an important N loss process in irrigated agriculture that imposes a cost on the farmer and the environment. A meta-analysis of published experimental results from agricultural irrigated systems was conducted to identify those strategies that have proven effective at reducing NL and to quantify the scale of reduction that can be achieved. Forty-four scientific articles were identified which investigated four main strategies (water and fertilizer management, use of cover crops and fertilizer technology) creating a database with 279 observations on NL and 166 on crop yield. Management practices that adjust water application to crop needs reduced NL by a mean of 80% without a reduction in crop yield. Improved fertilizer management reduced NL by 40%, and the best relationship between yield and NL was obtained when applying the recommended fertilizer rate. Replacing a fallow with a non-legume cover crop reduced NL by 50% while using a legume did not have any effect on NL. Improved fertilizer technology also decreased NL but was the least effective of the selected strategies. The risk of nitrate leaching from irrigated systems is high, but optimum management practices may mitigate this risk and maintain crop yields while enhancing environmental sustainability.
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The thermal and mechanical behaviour of isotactic polypropylene (iPP) nanocomposites reinforced with different loadings of inorganic fullerene-like tungsten disulfide (IF-WS2) nanoparticles was investigated. The IF-WS2 noticeably enhanced the polymer stiffness and strength, ascribed to their uniform dispersion, the formation of a large nanoparticle?matrix interface combined with a nucleating effect on iPP crystallization. Their reinforcement effect was more pronounced at high temperatures. However, a drop in ductility and toughness was found at higher IF-WS2 concentrations. The tensile behaviour of the nanocomposites was extremely sensitive to the strain rate and temperature, and their yield strength was properly described by the Eyring s equation. The activation energy increased while the activation volume decreased with increasing nanoparticle loading, indicating a reduction in polymer chain motion. The nanoparticles improved the thermomechanical properties of iPP: raised the glass transition and heat deflection temperatures while decreased the coefficient of thermal expansion. The nanocomposites also displayed superior flame retardancy with longer ignition time and reduced peak heat release rate. Further, a gradual rise in thermal conductivity was found with increasing IF-WS2 loading both in the glassy and rubbery states. The results presented herein highlight the benefits and high potential of using IF-nanoparticles for enhancing the thermomechanical properties of thermoplastic polymers compared to other nanoscale fillers.