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Long-term Viability (long-term + viability)
Selected AbstractsIn Vivo Perfusion of Human Skin Substitutes With Microvessels Formed by Adult Circulating Endothelial Progenitor CellsDERMATOLOGIC SURGERY, Issue 2 2008ELAINE F. KUNG MD BACKGROUND At present, tissue-engineered human skin substitutes (HSSs) mainly function as temporary bioactive dressings due to inadequate perfusion. Failure to form functional vascular networks within the initial posttransplantation period compromises cell survival of the graft and its long-term viability in the wound bed. OBJECTIVES Our goal was to demonstrate that adult circulating endothelial progenitor cells (EPCs) seeded onto HSS can form functional microvessels capable of graft neovascularization and perfusion. MATERIALS AND METHODS Adult peripheral blood mononuclear cells (PBMCs) underwent CD34 selection and endothelial cell (EC) culture conditions. After in vitro expansion, flow cytometry verified EC phenotype before their incorporation into HSS. After 2 weeks in vivo, immunohistochemical analysis, immunofluorescent microscopy, and microfil polymer perfusion were performed. RESULTS CD34+ PBMCs differentiated into EPC demonstrating characteristic EC morphology and expression of CD31, Tie-2, and E-selectin after TNF,-induction. Numerous human CD31 and Ulex europaeus agglutinin-1 (UEA-1) microvessels within the engineered grafts (HSS/EPCs) inosculated with recipient murine circulation. Limitation of murine CD31 immunoreactivity to HSS margins showed angiogenesis was attributable to human EPC at 2 weeks posttransplantation. Delivery of intravenous rhodamine-conjugated UEA-1 and microfil polymer to HSS/EPCs demonstrated enhanced perfusion by functional microvessels compared to HSS control without EPCs. CONCLUSION We successfully engineered functional microvessels in HSS by incorporating adult circulating EPCs. This autologous EC source can form vascular conduits enabling perfusion and survival of human bioengineered tissues. [source] A change process imbued with an Eastern ethos revitalizes an Indian businessGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 3 2005Edwina Pio In the rush to outsource to developing countries, global corporations would do well to understand,and leverage,the cultural differences they are likely to encounter in their offshore alliances. In a story of East meets West, the author describes how the marriage of progressive management concepts with uniquely Eastern values and mental models enabled an Indian firm to improve its processes, quality, and productivity in a quest to assure its own long-term viability and provide better value to its global partners. © 2005 Wiley Periodicals, Inc. [source] Relationship marketing, audience retention and performing arts organisation viabilityINTERNATIONAL JOURNAL OF NONPROFIT & VOLUNTARY SECTOR MARKETING, Issue 2 2002Ruth Rentschler Marketing strategy in performing arts organisations has become particularly important in the increasingly competitive environment in which the arts operate. Since the late 1980s there has been a necessary shift in focus to audience development away from product development. This change in focus is being encouraged to ensure the long-term viability of performing arts organisations (PAOs) and micro-economic reform. While government reports have recommended strategies aimed at building audience-based recognition, this is an expensive approach for many PAOs and does not produce short-term returns. Little attention has been paid to building enduring relationships with existing audiences as a way of having a more dramatic impact on PAOs' long-term viability. This paper explores this theme through relationship marketing and the implication of retaining existing audiences. The paper identifies the changing cultural environment which has led to the importance of marketing. It then explains the concepts of relationship marketing and its pertinence to PAOs' viability by presenting a loyalty ladder. The structure is modelled as a dynamic conceptualisation of the relationships (audience and organisation) to assist arts managers to decide whether to focus their efforts on catching or keeping customers to maximise earned income. Copyright © 2002 Henry Stewart Publications [source] Creating rural heritage visitor attractions,the Queensland Heritage Trails projectINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 4 2002Bruce Prideaux Abstract To promote rural heritage in Queensland, the Australian Federal and Queensland State Governments embarked on an ambitious funding programmeme titled the Queensland Heritage Trails Network commencing in 1999. The aim of the programmeme was to fund the development of a series of cultural heritage tourism attractions designed to encourage visitors to travel beyond popular coastal destinations and into the rural hinterland. For a state where travelling times by road are measured in days not hours, the development of visitor attractions away from the relatively closely settled coastal areas is essential if additional visitors are to be attracted to rural hinterland areas. However, distance factors add to the cost of travelling to many remote attractions and may deter all but the most determined travellers. This paper examines a number of demand side issues that may effect the long-term viability of many of the projects, particularly those in remote areas. Copyright © 2002 John Wiley & Sons, Ltd. [source] Scottish visitor attractions: a collaborative future?INTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 3 2001Alan Fyall Abstract Although interorganisational collaboration is increasingly being accepted as a necessary, even desirable strategy for the tourism industry as a whole, there would appear to be a number of impediments to the implementation of collaborative initiatives among operators of visitor attractions. This paper focuses on the visitor attractions sector in Scotland, where such impediments are considered to be particularly serious. For a number of reasons, however, collaboration may represent a crucial strategy for visitor attractions in Scotland as they enter the new millennium. This paper sets out to assess the potential for intrasectoral, interorganisational collaborative strategies in enhancing the long-term viability of the Scottish visitor attractions sector. Copyright © 2001 John Wiley & Sons, Ltd. [source] Corporate Acquisitions and the Operating Performance of Malaysian CompaniesJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 3-4 2004R. Abdul Rahman We report improvements in long run operating performance for a sample of Malaysian companies that made acquisitions over the period 1988,1992. As the sample selected consists of acquisitions of private target companies, the analysis allows us to focus on the possibility of changes arising from non-disciplinary sources. The reported improvements do not appear to have been achieved by sacrificing the long-term viability of the combined firms in pursuit of shortterm objectives. However, as the target companies in the current study were previously privately-owned businesses, researchers and policy makers should be wary before generalising from these results. [source] The ecological impacts of a migratory bat aggregation on its seasonal roost in Kasanka National Park, ZambiaAFRICAN JOURNAL OF ECOLOGY, Issue 1 2010James W. Byng Abstract The ecological impacts of migratory species on their seasonal environments are poorly known. The effects of several million straw-coloured fruit bats (Eidolon helvum), which migrate seasonally to Kasanka National Park, Zambia each year, on the small area of mushitu,swamp' forest in which they roost, were investigated. The structure of the mushitu forest was profoundly altered by the presence of E. helvum, with increased roost tree mortality, lowering and opening of the forest canopy and a decrease in tree basal area. Eidolon helvum are also thought to increase the severity of fires within their roost site because the structural changes result in a drier microclimate. The effects of increased nitrogen and phosphorous input were less apparent. These findings suggest that the ecological impact of this migratory bat species on its seasonal environment could ultimately threaten the long-term viability of its seasonal roost. Résumé Les impacts écologiques des espèces migratrices sur leurs environnements saisonniers sont peu connus. Les effets de plusieurs millions de roussettes paillées africaines Eidolon helvum qui, chaque année, migrent de façon saisonnière vers le Parc National de Kasanka, en Zambie, furent étudiés dans la petite zone de forêt marécageuse àmushitu où elles se perchent. La structure de la forêt àmushituétait profondément modifiée par la présence d'E. helvum, qui augmentait la mortalité des arbres servant de perchoirs, qui faisait baisser la hauteur et la densité de la canopée et entraînait une diminution de la surface basale des arbres. On pense aussi que la présence d'E. helvum augmente la gravité des feux dans les sites de repos parce que les changements structurels aboutissent à un microclimat plus sec. Les effets de l'apport accru en azote et en phosphore étaient moins apparents. Ces découvertes suggèrent que l'impact écologique de cette espèce de chauve-souris migratrice sur son environnement saisonnier pourrait, à long terme, menacer la viabilité de ses lieux de repos saisonniers. [source] The Present and Future of MFT Doctoral Education in Research-Focused UniversitiesJOURNAL OF MARITAL AND FAMILY THERAPY, Issue 3 2010Douglas H. Sprenkle Doctoral education is greatly impacted by context, and the large majority of marital and family therapy (MFT) doctoral programs are PhD programs in research-focused universities. I believe their primary mission is to equip students to become scientist,practitioners and do original research that will advance the science of the discipline, whereas the mission of the typical master's program is to produce strong practitioners who are research informed. It is the emphasis on the scientific method, not the content specialty area, that should be the hallmark of PhD programs in research-focused contexts. I describe metrics for success that include not only research productivity but also the development of a supportive, open, flexible, and generous program culture. The research mission of these programs has been only modestly helped by the Commission on Accreditation for Marriage and Family Therapy Education process and the programs are largely not doing the programmatic intervention research that the field needs. As the universities that house these programs are also "raising the bar," the long-term viability of the programs themselves will likely hinge on success in this arena. [source] DAM-INDUCED MODIFICATIONS TO UPPER ALLEGHENY RIVER STREAMFLOW PATTERNS AND THEIR BIODIVERSITY IMPLICATIONS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2002C. Mark Cowell ABSTRACT: This study evaluates the streamflow characteristics of the upper Allegheny River during the periods preceding (1936 to 1965) and following (1966 to 1997) completion of the Kinzua Dam in northwestern Pennsylvania. Inter-period trends in seasonal patterns of discharge and peak flow at three downstream sites are compared to those at two upstream sites to determine the influence of this large dam on surface water hydrology. Climatic records indicate that significant changes in annual total and seasonal precipitation occurred over the twentieth century. Increased runoff during the late summer through early winter led to increased discharge both upstream and downstream during these months, while slightly less early-year rainfall produced minor reductions in spring flood peaks since 1966. The Kinzua Dam significantly enhanced these trends downstream, creating large reductions in peak flow, while greatly augmenting low flow during the growing season. This reduction in streamflow variability, coupled with other dam-induced changes, has important biodiversity implications. The downstream riparian zone contains numerous threatened/endangered species, many of which are sensitive to the type of habitat modifications produced by the dam. Flood dynamics under the current post-dam conditions are likely to compound the difficulties of maintaining their long-term viability. [source] Variation in physiological health of diademed sifakas across intact and fragmented forest at Tsinjoarivo, eastern MadagascarAMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2010Mitchell T. Irwin Abstract As undisturbed habitat becomes increasingly rare, managers charged with ensuring the survival of endangered primate species must increasingly utilize disturbed and degraded habitats in species survival plans. Yet we have an imperfect understanding of the true long-term viability of primate populations in disturbed habitat, and census data can be misleading because density is not necessarily correlated with habitat quality and population viability in predictable ways. Here we present clinical laboratory data on hematology, serum biochemistry, fat-soluble vitamins, minerals, iron analytes, viral serology, and parasitology of diademed sifaka (Propithecus diadema), derived from the capture of 26 individuals spanning eight groups and two habitats (undisturbed vs. disturbed and fragmented) at Tsinjoarivo, Madagascar. Blood from fragment individuals had significantly lower values for several factors: white blood cell counts, bilirubin, total protein, albumin, calcium, sodium, chloride, manganese, zinc, iron and total iron-binding capacity. Several biochemical variables were higher in immature individuals, probably due to active growth. The large number of interhabitat differences suggests that habitat disturbance has an impact on physiological health within this population, perhaps reflecting dietary stress and/or immunosuppression. These results, combined with previous data showing altered diet, slower juvenile growth, and reduced activity in disturbed forest fragments, suggest that fragment sifakas may be less healthy than continuous forest groups. Finally, Tsinjoarivo sifakas have extremely low blood urea nitrogen (perhaps reflecting protein limitation) and selenium levels relative to other lemurs. Despite their survival and reproduction in the short term in fragments, these sifakas may represent a riskier conservation investment than conspecifics in undisturbed forest, and may be more susceptible to environmental stressors. However, more data on the fitness consequences of these biochemical differences are needed for a better interpretation of their impacts on long-term viability prospects. Am. J. Primatol. Am. J. Primatol. 72:1013,1025, 2010. © 2010 Wiley-Liss, Inc. [source] Landscape features and crustacean prey as predictors of the Southern river otter distribution in Chile.ANIMAL CONSERVATION, Issue 6 2009M. A. Sepúlveda Abstract Understanding the processes that affect freshwater ecosystems at the watershed level is fundamental for the conservation and management of river otters. During 2 consecutive years, we surveyed the occurrence of the Southern river otter Lontra provocax and its main prey (crustaceans) in a watershed of 9900 km2 in the Chilean temperate forest. We modeled predator and prey distributions with a variety of statistical techniques by relating a set of environmental predictors to species occurrence records. Otter and crustaceans were associated with areas of intermediate to low human disturbance with a mosaic of riparian vegetation densities, mainly at low altitudes. The singularity of the Andean Range, with a very marked elevation gradient and oligotrophic watercourses in the higher areas, created more vulnerable conditions for otter presence because prey abundances were limited in those areas. Human impacts affected otter populations at a landscape scale through the presence of main roads, as these were mostly located in lower parts of the watershed where otters have their primary habitat. These results point to the importance of land management and protection of low-elevation areas where otters still occur to ensure the long-term viability of its freshwater populations. [source] Assessing ecological changes in and around marine reserves using community perceptions and biological surveysAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2010M. Yasué Abstract 1. Well-enforced partial or total no-fishing zones (collectively known as marine protected areas, or MPAs) can help restore degraded coral reefs and enhance fish populations. 2. A comparison was made of community perceptions of ecological changes in an MPA with concurrent scientific data on these changes in the same MPA. Such analyses are particularly important in community-based MPAs where local support is a key determinant of ecological success. 3. The no-take MPA in question was initially launched in partnership with the community in 1995 and formalized in 1998. The perceptions data come from interviews with community members in 1999 and 2004, the biological data come from underwater visual censuses of the MPA from 1998 to 2004. 4. Community members perceived more fish within the MPA and slight increases in catch outside the MPA. In contrast, fish censuses showed a high degree of stochastic variation and only minor increases in fish abundance, size and diversity in and around the MPA between 1998 and 2004. 5. Possible explanations for these discrepancies include different temporal, spatial or species frames of reference and/or limitations to the biological survey technique. Other options include wishful thinking, external influences, a desire to please, or confounding with other benefits. 6. This study demonstrates some of the strengths and weaknesses of community perceptions and biological data. In order to improve our understanding about the changes that occur over time in an MPA and engender community support for the long-term viability of MPAs, it is important to develop diverse and efficient monitoring schemes. Copyright © 2010 John Wiley & Sons, Ltd. [source] Regulation versus pricing in urban water policy: the case of the Australian National Water InitiativeAUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 3 2006Joel Byrnes The Australian National Water Initiative (NWI) builds on the foundations of earlier water reforms, attempts to correct earlier errors in both policy and its implementation, and seeks to better define some of the policy aims with the benefit of hindsight. However, despite the deliberate effort to improve on earlier reforms, the NWI still embodies a significant economic paradox. Although policymakers have shown their faith in the market insofar as allocating water between competing agricultural interests is concerned, they have not shown the same degree of faith in the ability of urban users to respond to price signals. This paper attempts to shed at least some light on this question by examining the responses of a number of State governments across Australia to the NWI. The paper specifically explores the rationale for non-price regulation in the urban context but challenges the long-term viability of this approach. [source] Alginate,chitosan complex coacervation for cell encapsulation: Effect on mechanical properties and on long-term viabilityBIOPOLYMERS, Issue 6 2006Limor Baruch Abstract The use of chitosan in complexation with alginate appears to be a promising strategy for cell microencapsulation, due to the biocompatibility of both polymers and the high mechanical properties attributed by the use of chitosan. The present work focuses on the optimization and characterization of the alginate,chitosan system to achieve long-term cell encapsulation. Microcapsules were prepared from four types of chitosan using one- and two-stage encapsulation procedures. The effect of reaction time and pH on long-term cell viability and mechanical properties of the microcapsules was evaluated. Using the single-stage encapsulation procedure led to increase of at least fourfold in viability compared with the two-stage procedure. Among the four types of chitosan, the use of high molecular weight (MW) chitosan glutamate and low MW chitosan chloride provided high viability levels as well as good mechanical properties, i.e., more than 93% intact capsules. The high viability levels were found to be independent of the reaction conditions when using high MW chitosan. However, when using low MW chitosan, better viability levels (195%) were obtained when using a pH of 6 and a reaction time of 30 min. An alginate,chitosan cell encapsulation system was devised to achieve high cell viability levels as well as to improve mechanical properties, thus holding great potential for future clinical application. © 2006 Wiley Periodicals, Inc. Biopolymers 82:570,579, 2006 This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] | |||||||||||||