986 resultados para Small central hydroelectric. eng


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Small-scale dairy systems play an important role in the Mexican dairy sector and farm planning activities related to resource allocation have a significant impact on the profitability of such enterprises. Linear programming is a technique widely used for planning and ration formulation, and partial budgeting is a technique for assessing the impact of changes on the profitability of an enterprise. This study used both methods to optimise land use for forage production and nutrient availability, and to evaluate the economic impact of such changes in small-scale Mexican dairy systems. The model showed satisfactory performance when optimal solutions were compared with the traditional strategy. The strategy using fresh ryegrass, maize silage and oat hay, and the strategy using a combination of alfalfa hay, maize silage, fresh ryegrass and oat hay appeared attractive options for providing a better nutrient supply and maintaining a higher stocking rate throughout the year than the traditional strategy.

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There have been limited recent advances in understanding of what influences uptake of innovations despite the current international focus on smallholder agriculture as a means of achieving food security and rural development. This paper provides a rigorous study of factors influencing adoption by smallholders in central Mexico and builds on findings to identify a broad approach to significantly improve research on and understanding of factors influencing adoption by smallholders in developing countries. Small-scale dairy systems play an important role in providing income, employment and nutrition in the highlands of central Mexico. A wide variety of practices and technologies have been promoted by the government public services to increase milk production and economic efficiency, but there have been very low levels of uptake of most innovations, with the exception of improving grassland through introduction of grass varieties together with management practices. A detailed study was conducted with 80 farmers who are already engaged with the use of this innovation to better understand the process of adoption and identify socioeconomic and farm variables, cognitive (beliefs), and social–psychological (social norms) factors associated with farmers' use of improved grassland. The Theory of Reasoned Action (TRA) was used as a theoretical framework and Spearman Rank Order correlation was conducted to analyse the data. Most farmers (92.5%) revealed strong intention to continue to use improved grassland (which requires active management and investment of resources) for the next 12 months; whereas 7.5% of farmers were undecided and showed weak intention, which was associated with farmers whose main income was from non-farm activities as well as with farmers who had only recently started using improved grassland. Despite farmers' experience of using improved grassland (mean of 18 years) farmers' intentions to continue to adopt it was influenced almost as much by salient referents (mainly male relatives) as by their own attitudes. The hitherto unnoticed longevity of the role social referents play in adoption decisions is an important finding and has implications for further research and for the design of extension approaches. The study demonstrates the value and importance of using TRA or TPB approaches to understand social cognitive (beliefs) and social–psychological (social norms) factors in the study of adoption. However, other factors influencing adoption processes need to be included to provide fuller understanding. An approach that would enable this, and the development of more generalisable findings than from location specific case studies, and contribute to broader conceptualisation, is proposed.

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The present study describes and evaluates the horizontal and vertical structures of a lowland forest fragment on a hillock in the municipality of Silva Jardim, Rio de Janeiro State, Brazil (22 degrees 31`56 `` S and 42 degrees 20`46 `` W). Twenty plots (10x2m) totaling 0.5ha were laid out following the slope grade using DBH >= 5cm as the inclusion criterion. A total of 734 individuals were encountered, yielding a total density of 1468 ind./ha and a total basal area of 10783m(2). The richness values (129 species/41 families), Shannon-Wiener diversity (4.22) and equitability (0.87) indices indicated an accentuated floristic heterogeneity and low ecological dominance. Lauraceae, Myrtaceae, Fabaceae and Euphorbiaceae showed the greatest species richness, corroborating other studies that indicated these species as the most representative of Atlantic Forest areas in southeastern Brazil. The species with the greatest importance values (VI) were Aparisthmium cordatum, Guapira opposita, Lacistema pubescens, Xylopia sericea, Tapirira guianensis and Piptocarpha macropoda. The high diversity observed was influenced by earlier anthropogenic actions and by the current successional stage. The forest fragment studied demonstrated closer floristic similarity to areas inventoried in a close-by biological reserve than to fragments dispersed throughout the coastal plain. Similarities in soil type, degree of soil saturation and use-history of forest resources all support these relationships. The fragmented physiognomy of the central lowland in this region and the use-history of the landscape make these small remnant forest areas important in terms of establishing strategies for landscape restoration and species conservation.

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This Minor Field Study was carried out during November and December in 2011 in the Mount Elgon District in Western Kenya. The objective was to examine nine small-scale farming household´s land use and socioeconomic situation when they have joined a non-governmental organization (NGO) project, which specifically targets small-scale farming households to improve land use system and socioeconomic situation by the extension of soil and water conservation measures. The survey has worked along three integral examinations methods which are mapping and processing data using GIS, semi structured interviews and literature studies.   This study has adopted a theoretical approach referred to as political ecology, in which landesque capital is a central concept. The result shows that all farmers, except one, have issues with land degradation. However, the extent of the problem and also implemented sustainable soil and water conservation measures were diverse among the farmers. The main causes of this can both be linked to how the farmers themselves utilized their farmland and how impacts from the climate change have modified the terms of the farmers working conditions. These factors have consequently resulted in impacts on the informants’ socioeconomic conditions. Furthermore it was also registered that social and economic elements, in some cases, were the causes of how the farmers manage their farmland. The farmer who had no significant problem with soil erosion had invested in trees and opportunities to irrigate the farmland. In addition, it was also recorded that certain farmers had invested in particular soil and water conservation measures without any significant result. This was probably due to the time span these land measures cover before they start to generate revenue.  The outcome of this study has traced how global, national and local elements exist in a context when it comes to the conditions of the farmers´ land use and their socioeconomic situation. The farmers atMt.Elgon are thereby a component of a wider context when they are both contributory to their socioeconomic situation, mainly due to their land management, and also exposed to core-periphery relationships on which the farmers themselves have no influence.

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The goal of this paper is to examine the relationship between real GDP and oil prices using time series data for the period 1970–2005. Our main finding is that an increase in oil has a positive, albeit inelastic, impact on real GDP, inconsistent with the bulk of the literature. We argue that this is not a surprising result for the Fiji Islands. Our central argument focuses on two aspects of the Fijian economy: (1) the fact that actual output in Fiji has been around 50 per cent less than potential output; thus, Fiji's actual output has not reached a threshold level at which oil prices can negatively impact output; and (2) a rise in oil prices filters through to value added, which in turn is reflected in a larger actual output.

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Stipe lengths of sporophytes of Ecklonia cava Kjellman have been reported to be longer along the southeast than southwest coast of the Izu Peninsula, central Japan. Two bays in this region that have natural populations of E. cava, but with different stipe lengths, were chosen for transplant experiments to examine if stipe length was an environmentally controlled trait. Transplant experiments were carried out in order to determine whether large-type sporophytes of E. cava with long stipes growing in Nabeta Bay (southeast Izu Peninsula, Japan) would turn into small-type sporophytes with short stipes when transplanted to Nakagi Bay (southwest Izu Peninsula). Ten juvenile sporophytes of E. cava (stipe length < 5 cm) were collected from Nabeta Bay (large-type habitat) and transplanted to Nakagi Bay (short-type habitat) in December 1995. As a transplant control, ten juvenile sporophytes of E. cava growing in Nakagi Bay were also transplanted to the same artificial reefs. Growth and survival rates of the sporophytes were monitored monthly for 3 y until December 1998. The transplanted sporophytes showed an increase in their stipe length and diameter from winter to spring, whereas almost no increase was observed from summer to autumn. However, the elongation was greater in Nabeta sporophytes than in Nakagi sporophytes. The primary blade length increased mainly from winter to early spring and decreased largely in autumn. Average primary blade lengths were similar in both Nabeta and Nakagi sporophytes from the end of the first year of transplanting. Although ca. 70% of both Nabeta and Nakagi sporophytes survived during the first 2 y after transplantation, no Nakagi sporophytes and only two Nabeta sporophytes survived to the end of the 3 y study period. Despite transplantation to Nakagi Bay, where short sitpes are naturally present, the sporophytes from Nabeta Bay persisted in having longer stipes, which suggests that stipe length is genetically, rather than environmentally, controlled.

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This research investigates the relationship between principalship and policy in small New Zealand primary schools. A distinctive feature of small primary schools is that their principals typically have to teach as well as manage. Overseas research indicates that in times of educational reform, teaching principals face particular difficulty and may need special support. Following the watershed educational reforms of 1989 and a decade of ‘hands-off’ policy in education (1989-1999), central policy towards school support in New Zealand is now more ‘hands-on’. The impact of this policy change on small schools has not been researched hi New Zealand, where such schools make up over fifty percent of all primary schools. The aims of this study are to analyse the impact of current support policy in New Zealand on small primary school principalship, and to evaluate the extent to which policy adjustment might be needed in the future. Using multiple methods and a case study approach to gather data, the study focuses on small school principalship in one New Zealand region - the Central Districts region. It also considers the recent policy initiatives, their rationale and the extent to which they appear to be meeting the support needs reported by the principals whose work has been researched in the study. Broadly, the study has found that within small schools, the role-balance within a teaching principal’s work is a critical factor, as the ratio within the principal’s role-balance between the teaching role and the management role creates variation in work-demands, work-strategies and types of support needed. Teaching principals in New Zealand generally feel better supported now than they did in the 1990s and the study identifies factors associated with this change. However the analysis in this study suggests that the current policy aim to both rationalise and strengthen the small school network as a whole is rather problematic. Without better targeted support policy in this area, old style parochial and competitive attitudes between schools are unlikely to change in the future.

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Purpose – The purpose of this paper is to illustrate the potential for green roof retrofit to commercial buildings in a city centre to property managers and other property professionals.

Design/methodology/approach – This paper addresses the research question: what is the potential of existing buildings in the CBD to accommodate a retrofitted green roof? Furthermore, it questions how many buildings are suitable for green roofs? The researchers compile a unique building database incorporating information about 536 commercial buidings and evaluate the potential suitability of each building to undergo a green roof retrofit. Assisted by other commercially available databases and software, the researchers are able to assess each roof based on criteria derived from an extensive literature review.

Findings – A relatively small proportion of roofs are found to be suitable, partly a result of local climate conditions and rainfall patterns, and the physical property stock. On a purely physical assessment, only a very small proportion of CBD stock is found to be suited. These buildings are most likely to be in low secondary locations, ungraded or B grade buildings, privately owned, concrete framed and not overshadowed by adjoining properties.

Practical implications –
Property managers and other property professionals can now determine the potential of their portfolio stock for green roof retrofit based on the review of building attributes required for success adaptation in this paper. It possible that greater potential for green roof retrofit exists in the suburbs or regional towns where lower rise buildings may reduce the amount of overshadowing found in city centres. Follow-up research could focus on a comparison of regional and suburban developments.

Originality/value – This is the first study of its kind and has assessed such a large number of buildings for their suitability for green roof retrofit; the findings provide a reliable guide for policymakers regarding the potential number of city centre buildings which would be possible to retrofit. Such findings should influence policymaking and incentives to target effective sustainability policies with regards to existing buildings.

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Survivin is a dual functioning protein. It inhibits the apoptosis of cancer cells by inhibiting caspases, and also promotes cancer cell growth by stabilizing microtubules during mitosis. Since the molecular chaperone Hsp90 binds and stabilizes survivin, it is widely believed that down-regulation of survivin is one of the important therapeutic functions of Hsp90 inhibitors such as the phase III clinically trialed compound 17-AAG. However, Hsp90 interferes with a number of molecules that up-regulate the intracellular level of survivin, raising the question that clinical use of Hsp90 inhibitors may indirectly induce survivin expression and subsequently enhance cancer anti-drug responses. The purpose of this study is to determine whether targeting Hsp90 can alter survivin expression differently in different cancer cell lines and to explore possible mechanisms that cause the alteration in survivin expression.

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A central issue of this thesis has been an examination of the effects that the current wool crisis has had on the Balmoral district, an area almost solely devoted to the production of wool and wool sheep. Examines the methods being utilised to try to alleviate some of these effects.

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A key task in ecology is to understand the drivers of animal distributions. In arid and semi-arid environments, this is challenging because animal populations show considerable spatial and temporal variation. An effective approach in such systems is to examine both broad-scale and long-term data. We used this approach to investigate the distribution of small mammal species in semi-arid ‘mallee’ vegetation in south-eastern Australia. First, we examined broad-scale data collected at 280 sites across the Murray Mallee region. We used generalized additive mixed models (GAMMs) to examine four hypotheses concerning factors that influence the distribution of individual mammal species at this scale: vegetation structure, floristic diversity, topography and recent rainfall. Second, we used long-term data from a single conservation reserve (surveyed from 1997 to 2012) to examine small mammal responses to rainfall over a period spanning a broad range of climatic conditions, including record high rainfall in 2011. Small mammal distributions were strongly associated with vegetation structure and rainfall patterns, but the relative importance of these drivers was species-specific. The distribution of the mallee ningaui Ningaui yvonneae, for example, was largely determined by the cover of hummock grass; whereas the occurrence of the western pygmy possum Cercartetus concinnus was most strongly associated with above-average rainfall. Further, the combination of both broad-scale and long-term data provided valuable insights. Bolam's mouse Pseudomys bolami was uncommon during the broad-scale survey, but long-term surveys showed that it responds positively to above-average rainfall. Conceptual models developed for small mammals in temperate and central arid Australia, respectively, were not, on their own, adequate to account for the distributional patterns of species in this semi-arid ecosystem. Species-specific variation in the relative importance of different drivers was more effectively explained by qualitative differences in life-history attributes among species.

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Aims This paper describes the refinement and adaptation to small business of a previously developed method for systematically prioritizing needs for intervention on hazardous substance exposures in manufacturing worksites, and evaluating intervention effectiveness. Methods We developed a checklist containing six unique sets of yes/no variables organized in a 2 × 3 matrix of exposure potential versus exposure protection at three levels corresponding to a simplified hierarchy of controls: materials, processes, and human interface. Each of the six sets of indicator variables was reduced to a high/moderate/low rating. Ratings from the matrix were then combined to generate an exposure prevention 'Small Business Exposure Index' (SBEI) Summary score for each area. Reflecting the hierarchy of controls, material factors were weighted highest, followed by process, and then human interface. The checklist administered by an industrial hygienist during walk-through inspection (N = 149 manufacturing processes/areas in 25 small to medium-sized manufacturing worksites). One area or process per manufacturing department was assessed and rated. A second hygienist independently assessed 36 areas to evaluate inter-rater reliability. Results The SBEI Summary scores indicated that exposures were well controlled in the majority of areas assessed (58% with rating of 1 or 2 on a 6-point scale), that there was some room for improvement in roughly one-third of areas (31% of areas rated 3 or 4), and that roughly 10% of the areas assessed were urgently in need of intervention (rated as 5 or 6). Inter-rater reliability of EP ratings was good to excellent (e.g., for SBEI Summary scores, weighted kappa = 0.73, 95% CI 0.52–0.93). Conclusion The SBEI exposure prevention rating method is suitable for use in small/medium enterprises, has good discriminatory power and reliability, offers an inexpensive method for intervention needs assessment and effectiveness evaluation, and complements quantitative exposure assessment with an upstream prevention focus.

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Background The aim of this study was to examine the distribution of physical activity facilities by area-level deprivation in Scotland, adjusting for differences in urbanicity, and exploring differences between and within the four largest Scottish cities. Methods We obtained a list of all recreational physical activity facilities in Scotland. These were mapped and assigned to datazones. Poisson and negative binomial regression models were used to investigate associations between the number of physical activity facilities relative to population size and quintile of area-level deprivation. Results The results showed that prior to adjustment for urbanicity, the density of all facilities lessened with increasing deprivation from quintiles 2 to 5. After adjustment for urbanicity and local authority, the effect of deprivation remained significant but the pattern altered, with datazones in quintile 3 having the highest estimated mean density of facilities. Within-city associations were identified between the number of physical activity facilities and area-level deprivation in Aberdeen and Dundee, but not in Edinburgh or Glasgow. Conclusions In conclusion, area-level deprivation appears to have a significant association with the density of physical activity facilities and although overall no clear pattern was observed, affluent areas had fewer publicly owned facilities than more deprived areas but a greater number of privately owned facilities.

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The mud crab, Scylla olivacea, is one of the most economically valuable marine species in Southeast Asian countries. However, commercial cultivation is disadvantaged by reduced reproductive capacity in captivity. Therefore, an understanding of the general and detailed anatomy of central nervous system (CNS) is required before investigating the distribution and functions of neurotransmitters, neurohormones, and other biomolecules, involved with reproduction. We found that the anatomical structure of the brain is similar to other crabs. However, the ventral nerve cord (VNC) is unlike other caridian and dendrobrachiate decapods, as the subesophageal (SEG), thoracic and abdominal ganglia are fused, due to the reduction of abdominal segments and the tail. Neurons in clusters within the CNS varied in sizes, and we found that there were five distinct size classes (i.e., very small globuli, small, medium, large, and giant). Clusters in the brain and SEG contained mainly very small globuli and small-sized neurons, whereas, the VNC contained small-, medium-, large-, and giant-sized neurons. We postulate that the different sized neurons are involved in different functions. Microsc. Res. Tech. 77:189–200, 2014. © 2013 Wiley Periodicals, Inc.

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Background: Spontaneous gastrointestinal neoplasms in non-human primates are commonly seen in aged individuals. Due to genetic similarities between human and non-human primates, scientists have shown increasing interest in terms of comparative oncology studies.Case presentation: The present study is related to a case of an intestinal leiomyoma in a black crested macaque (Macaca nigra), kept on captivity by Mateca a Zoo, Pereira City, Colombia. The animal had abdominal distension, anorexia, vomiting, diarrhea and behavioral changes. Clinical examination showed an increased volume in the upper right abdominal quadrant caused by a neoplastic mass. The patient died during the surgical procedure. Necropsy revealed several small nodules in the peritoneum with adhesion to different portions of the small and large intestines, liver, stomach and diaphragm. Tissue samples were collected, routinely processed and stained by H&E. Microscopic examination revealed a mesenchymal tumor limited to tunica muscularis, resembling normal smooth muscle cells. Neoplastic cells were positive for alpha-smooth muscle actin and vimentin, and negative for cytokeratin AE1/AE3 by immunohistochemistry. Those morphological and immunohistochemical findings allowed to diagnose the intestinal leiomyoma referred above.Conclusion: Neoplastic diseases in primates have multifaceted causes. Their manifestations are understudied, leading to a greater difficulty in detection and measurement of the real impact provides by this disease.