106 resultados para LINKAGES
Resumo:
The selective fermentation by human gut bacteria of gluco-oligosaccharides obtained from the reaction between the glucosyl group of sucrose and cellobiose, catalyzed by dextransucrases (DSR) from Leuconostoc mesenteroides, has been evaluated. Oligosaccharides were fractionated according to their molecular weight, and their effect on the growth of different bacterial groups was studied. To determine the structure (position and configuration of glycosidic linkages)�function relationship, their properties were compared to those of DSR maltose acceptor products (DSRMal) and of recognized prebiotic carbohydrates (fructo-oligosaccharides, FOS). Cellobiose acceptor products (DSRCel) showed bifidogenic properties similar to those of FOS. However, no significant differences related to molecular weight or isomeric configurations were found for DSRCel and DSRMal products.
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Cyanobacteria (blue-green algae) blooms in water bodies present serious public health issues with attendant economic and ecological impacts. Llyn Tegid (Lake Bala) is an important conservation and amenity asset within Snowdonia National Park, Wales which since the mid-1990s has experienced multiple toxic cyanobacteria blooms threatening the ecology and tourism-dependent local economy. Multiple working hypotheses explain the emergence of this problem, including climate change, land management linked to increased nutrient flux, hydromorphological alterations or changing trophic structure - any of which may operate individually or cumulatively to impair lake function. This paper reports the findings of a sedimentfingerprinting study using dated lake cores to explore the linkages between catchment and lake management practices and the emergence of the algal blooms problem. Since 1900 AD lake bed sedimentation rates have varied from 0.06 to 1.07 g cm−2 yr−1, with a pronounced acceleration since the early 1980s. Geochemical analysis revealed increases in the concentrations of total phosphorus (TP), calcium and heavy metals such as zinc and lead consistent with eutrophication and a rising pollution burden, particularly since the late 1970s. An uncertainty-inclusive sedimentfingerprinting approach was used to apportion the relative fluxes from the major catchment land cover types of improved pasture, rough grazing, forestry and channel banks. This showed improved pasture and channel banks are the dominant diffuse sources of sediment in the catchment, though forestry sources were important historically. Conversion of rough grazing to improved grassland, coupled with intensified land management and year-round livestock grazing, is concluded to provide the principal source of rising TP levels. Lake Habitat Survey and particle size analysis of lake cores demonstrate the hydromorphological impact of the River Dee Regulation Scheme, which controls water level and periodically diverts flow into Llyn Tegid from the adjacent Afon Tryweryn catchment. This hydromorphological impact has also been most pronounced since the late 1970s. It is concluded that an integrated approach combining land management to reduce agricultural runoff allied to improved water level regulation enabling recovery of littoral macrophytes offers the greatest chance halting the on-going cyanobacteria issue in Llyn Tegid.
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International competitiveness ultimately depends upon the linkages between a firm’s unique, idiosyncratic capabilities (firm-specific advantages, FSAs) and its home country assets (country-specific advantages, CSAs). In this paper, we present a modified FSA/CSA matrix building upon the FSA/CSA matrix (Rugman 1981). We relate this to the diamond framework for national competitiveness (Porter 1990), and the double diamond model (Rugman and D’Cruz 1993). We provide empirical evidence to demonstrate the merits and usefulness of the modified FSA/CSA matrix using the Fortune Global 500 firms. We examine the FSAs based on the geographic scope of sales and CSAs that can lead to national, home region, and global competitiveness. Our empirical analysis suggests that the world’s largest 500 firms have increased their firm-level international competitiveness. However, much of this is still being achieved within their home region. In other words, international competitiveness is a regional not a global phenomenon. Our findings have significant implications for research and practice. Future research in international marketing should take into account the multi-faceted nature of FSAs and CSAs across different levels. For MNE managers, our study provides useful insights for strategic marketing planning and implementation.
Resumo:
With increasing emphasis being placed on concentrating development in urban areas and improving the quality of life in British cities and towns, the importance of accommodating necessary development without compromising the valued heritage and architectural quality of urban areas is now becoming central to sustainable urban development. Urban conservation policy and practice has the potential to contribute to this and other aspects of sustainability. This paper explores this contribution and develops an analytical framework which draws out the key linkages between conservation area policy and sustainable development. The framework is then used to research the potential and actual contribution of urban conservation policy and practice in England, using a selective survey and two case studies (i.e. Winchester and Basingstoke). The main conclusions from the research are that: Conservation area policy can make a significant contribution to the principles of sustainable development; Most local planning authorities in England have not fully woken-up to this potential and have not developed policies or practices to address it; and Urban conservation policy needs to develop a more proactive approach in which local planning authorities actively guide and encourage new development with regard to use, design, layout, methods of construction, materials and energy efficiency.
Resumo:
Practical applications of portfolio optimisation tend to proceed on a “top down” basis where funds are allocated first at asset class level (between, say, bonds, cash, equities and real estate) and then, progressively, at sub-class level (within property to sectors, office, retail, industrial for example). While there are organisational benefits from such an approach, it can potentially lead to sub-optimal allocations when compared to a “global” or “side-by-side” optimisation. This will occur where there are correlations between sub-classes across the asset divide that are masked in aggregation – between, for instance, City offices and the performance of financial services stocks. This paper explores such sub-class linkages using UK monthly stock and property data. Exploratory analysis using clustering procedures and factor analysis suggests that property performance and equity performance are distinctive: there is little persuasive evidence of contemporaneous or lagged sub-class linkages. Formal tests of the equivalence of optimised portfolios using top-down and global approaches failed to demonstrate significant differences, whether or not allocations were constrained. While the results may be a function of measurement of market returns, it is those returns that are used to assess fund performance. Accordingly, the treatment of real estate as a distinct asset class with diversification potential seems justified.
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Adaptive Social Protection refers to efforts to integrate social protection (SP), disaster risk reduction (DRR) and climate change adaptation (CCA). The need to integrate these three domains is now increasingly recognized by practitioners and academics. Relying on 124 agricultural programmes implemented in 5 countries in Asia, this paper considers how these elements are being brought together, and explores the potential gains of these linkages. The analysis shows that full integration of SP, DRR and CCA interventions is still relatively limited but that when it occurs, integration helps to shift the time horizon beyond short-term interventions aimed at supporting peoples’ coping strategies and/or graduation objectives, toward longer-term interventions that can assist in promoting transformation towards climate and disaster resilient livelihood options.
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This paper examined the incidence of intrafirmcausalambiguity in the management's perception concerning the critical drivers of their firms’ performance. Building on insights from the resource-based view we developed and tested hypotheses that examine (1) linkage ambiguity as a discrepancy between perceived and measured resource–performance linkages, (2) characteristic ambiguity for resources and capabilities with a high degree of complexity and tacitness, and (3) the negative association between linkage ambiguity and performance. The observations based on the explicit perceptions of 356 surveyed managers were contrasted with the empirical findings of the resource/performance relationship derived by structural equation modelling from the same data sample. The findings validate the presence of linkage ambiguity particularly in the case of resources and capabilities with higher degree of characteristic ambiguity. The findings also provide empirical evidence in support of the advocacy for a negative relationship between intrafirmcausalambiguity and performance. The paper discusses the potential reasons for the disparities between empirical findings and management's perceptions of the key determinants of export success and makes recommendations for future research.
Resumo:
Snakebites are a major neglected tropical disease responsible for as many as 95000 deaths every year worldwide. Viper venom serine proteases disrupt haemostasis of prey and victims by affecting various stages of the blood coagulation system. A better understanding of their sequence, structure, function and phylogenetic relationships will improve the knowledge on the pathological conditions and aid in the development of novel therapeutics for treating snakebites. A large dataset for all available viper venom serine proteases was developed and analysed to study various features of these enzymes. Despite the large number of venom serine protease sequences available, only a small proportion of these have been functionally characterised. Although, they share some of the common features such as a C-terminal extension, GWG motif and disulphide linkages, they vary widely between each other in features such as isoelectric points, potential N-glycosylation sites and functional characteristics. Some of the serine proteases contain substitutions for one or more of the critical residues in catalytic triad or primary specificity pockets. Phylogenetic analysis clustered all the sequences in three major groups. The sequences with substitutions in catalytic triad or specificity pocket clustered together in separate groups. Our study provides the most complete information on viper venom serine proteases to date and improves the current knowledge on the sequence, structure, function and phylogenetic relationships of these enzymes. This collective analysis of venom serine proteases will help in understanding the complexity of envenomation and potential therapeutic avenues.
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Widely distributed proxy records indicate that the Medieval Climate Anomaly (MCA; *900–1350 AD) was characterized by coherent shifts in large-scale Northern Hemisphere atmospheric circulation patterns. Although cooler sea surface temperatures in the central and eastern equatorial Pacific can explain some aspects of medieval circulation changes, they are not sufficient to account for other notable features, including widespread aridity through the Eurasian sub-tropics, stronger winter westerlies across the North Atlantic and Western Europe, and shifts in monsoon rainfall patterns across Africa and South Asia. We present results from a full-physics coupled climate model showing that a slight warming of the tropical Indian and western Pacific Oceans relative to the other tropical ocean basins can induce a broad range of the medieval circulation and climate changes indicated by proxy data, including many of those not explained by a cooler tropical Pacific alone. Important aspects of the results resemble those from previous simulations examining the climatic response to the rapid Indian Ocean warming during the late twentieth century, and to results from climate warming simulations—especially in indicating an expansion of the Northern Hemisphere Hadley circulation. Notably, the pattern of tropical Indo-Pacific sea surface temperature (SST) change responsible for producing the proxy-model similarity in our results agrees well with MCA-LIA SST differences obtained in a recent proxy-based climate field reconstruction. Though much remains unclear, our results indicate that the MCA was characterized by an enhanced zonal Indo-Pacific SST gradient with resulting changes in Northern Hemisphere tropical and extra-tropical circulation patterns and hydroclimate regimes, linkages that may explain the coherent regional climate shifts indicated by proxy records from across the planet. The findings provide new perspectives on the nature and possible causes of the MCA—a remarkable, yet incompletely understood episode of Late Holocene climatic change.
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This paper critically examines the impact of the ‘Guidelines for Hariyali’ – a rural watershed development policy launched in Rajasthan, Western India which has been implemented through a Public Private Partnership (PPP) – for local communities. In 2003, the Government of India launched the ‘Guidelines’ (a comprehensive Integrated Wastelands Development Programme and Drought Prone Areas Programme and Desert Development Programme), the purpose of which is to restore ecological balance by harnessing, conserving and developing natural resources in drought-prone and arid rural areas for the benefit of villages. In the particular case-study area, the policy has been implemented through institutional linkages between a corporation and the government with the aim of sharing responsibilities for finances, planning, implementation and monitoring, the end goal being to enhance the livelihoods of rural households. The analysis focuses specifically on how the ‘Guidelines’ have affected the livelihoods of Rajasthani women, drawing upon findings from focus groups with men and women in the project catchment area, as well as interviews with key actors at public and private sector institutions. Findings reveal that there are significant gaps between policy objectives and the realities on the ground, particularly in the context of women's accessibilities and entitlements. The paper also broadens understanding of how PPPs, if implemented properly, could empower women in the area of watershed management across rural South Asia.
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Let 0 denote the level of quality inherent in a food product that is delivered to some terminal market. In this paper, I characterize allocations over 0 and provide an economic rationale for regulating safety and quality standards in the food system. Zusman and Bockstael investigate the theoretical foundations for imposing standards and stress the importance of providing a tractable conceptual foundation. Despite a wealth of contributions that are mainly empirical (for reviews of these works see, respectively, Caswell and Antle), there have been relatively few attempts to model formally the linkages between farm and food markets when food quality and consumer safety are at issue. Here, I attempt to provide such a framework, building on key contributions in the theoretical literature and linking them in a simple model of quality determination in a vertically related marketing channel. The food-marketing model is due to Gardner. Spence provides a foundation for Pareto-improving intervention in a deterministic model of quality provision, and Leland, building on the classic paper by Akerlof, investigates licensing and minimum standards when the information structure is incomplete. Linking these ideas in a satisfactory model of the food markets is the main objective of the paper.
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We exploit a theory of price linkages that lends itself readily to empirical examination using Markovchain, Monte Carlo methods. The methodology facilitates classification and discrimination among alternative regimes in economic time series. The theory and procedures are applied to annual series (1955-1992) on the U.S. beef sector
Resumo:
The paper explores the relationships between UK commercial real estate and regional economic development as a foundation for the analysis of the role of real estate investment in local economic development. Linkages between economic growth, development, real estate performance and investment allocations are documented. Long-run regional property performance is not the product of long-run economic growth, and weakly related to indicators of long-run supply and demand. Changes in regional portfolio weights seem driven by neither market performance nor underlying fundamentals. In the short run, regional investment shifts show no clear leads or lags with market performance.
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This paper examines biogas innovation system and processes in two farming communities in Davao del Sur, Philippines. Innovation histories were traced through workshops, semi-structured interviews, observations and document analysis. The paper shows that there were diverse innovation actors both from public and private sectors. Restrictive attitudes and practices resulted in weak and limited interactions among actors. Multi-actor interaction was weak, signifying a lack of innovation actors that focus on creating, developing and strengthening linkages, networks and partnerships. The lack of support in the socio-organisational institutions that constitute the enabling environment within which innovation actors operate may lead to systemic failure.
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The relationship between price volatility and competition is examined. Atheoretic, vector auto regressions on farm prices of wheat and retail prices of derivatives (flour, bread, pasta, bulgur and cookies) are compared to results from a dynamic, simultaneous-equations model with theory-based farm-to-retail linkages. Analytical results yield insights about numbers of firms and their impacts on demand- and supply-side multipliers, but the applications to Turkish time series (1988:1-1996:12) yield mixed results.