2,570 research outputs found

    Do Small, Patchy, Constructed Intertidal Oyster Reefs Reduce Salt Marsh Erosion As Well As Natural Reefs?

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    One ecological service that oyster reefs provide is stabilization of shorelines through reduced wave energy and erosion from boat traffic, storms, and predominant wind direction. Additionally, increasing sedimentation can enhance the growth of emergent marsh vegetation which further stabilizes unconsolidated sediments. A 21 mo study of constructed (with only 30-35% coverage) and natural oyster reefs in 3 bayous in the Grand Bay National Estuarine Research Reserve (NERR) suggested constructed reefs benefit this retrograding deltaic ecosystem. The marsh edge adjacent to all constructed reefs was less eroded (mean = 0.043 m) than edges adjacent to natural reefs (mean = 0.728 m), although all natural and constructed sites, regardless of bayou, illustrated large variations in marsh edge growth. The marsh edge in constructed sites in one bayou retreated more than in the other bayous, most likely due to its coarser sediments, greater boat traffic, and its apparent higher energy location within the landscape. By the end of this study, the ecological function of constructed oyster reefs in all bayous, as measured by marsh edge erosion reduction, was equivalent or exceeded the function in nearby natural oyster reefs. The physical structure of the reef further served to reduce erosion and marsh loss and this approach may be useful for management of a retrograding deltaic estuarine ecosystem like the Grand Bay NERR

    Universities and community-based research in developing countries: community voice and educational provision in rural Tanzania

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    The main focus of recent research on the community engagement role of universities has been in developed countries, generally in towns and cities and usually conducted from the perspectives of universities rather than the communities with which they engage. The purpose of this paper is to investigate the community engagement role of universities in the rural areas of developing countries, and its potential for strengthening the voice of rural communities. The particular focus is on the provision of primary and secondary education. The paper is based on the assumption that in order for community members to have both the capacity and the confidence to engage in political discourse for improving educational capacity and quality, they need the opportunity to become involved and well-versed in the options available, beyond their own experience. Particular attention is given in the paper to community-based research (CBR). CBR is explored from the perspectives of community members and local leaders in the government-community partnerships which have responsibility for the provision of primary and secondary education in rural Tanzania. The historical and policy background of the partnerships, together with findings from two case studies, provide the context for the paper

    TQM implementation: An empirical examination and proposed generic model

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    Total quality management (TQM) is considered by many as an important quality and business performance improvement tool. The popularity of the concept has led to an explosion of TQM related literature. A careful review of the literature suggests that most publications recount the experiences or perceptions of the authors or deal with single case organisations. Furthermore, there is a dearth of empirical research and literature dealing with TQM's implementation process. This paper reports the findings of a research project that empirically examined the process of TQM implementation in a sample of organisations widely regarded as leading exponents of TQM. The paper presents a non-prescriptive model of the TQM implementation process derived from the findings and proposes an "outcome driven" approach as an alternative to the more commonplace TQM implementation strategies

    A mathematical model for breath gas analysis of volatile organic compounds with special emphasis on acetone

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    Recommended standardized procedures for determining exhaled lower respiratory nitric oxide and nasal nitric oxide have been developed by task forces of the European Respiratory Society and the American Thoracic Society. These recommendations have paved the way for the measurement of nitric oxide to become a diagnostic tool for specific clinical applications. It would be desirable to develop similar guidelines for the sampling of other trace gases in exhaled breath, especially volatile organic compounds (VOCs) which reflect ongoing metabolism. The concentrations of water-soluble, blood-borne substances in exhaled breath are influenced by: (i) breathing patterns affecting gas exchange in the conducting airways; (ii) the concentrations in the tracheo-bronchial lining fluid; (iii) the alveolar and systemic concentrations of the compound. The classical Farhi equation takes only the alveolar concentrations into account. Real-time measurements of acetone in end-tidal breath under an ergometer challenge show characteristics which cannot be explained within the Farhi setting. Here we develop a compartment model that reliably captures these profiles and is capable of relating breath to the systemic concentrations of acetone. By comparison with experimental data it is inferred that the major part of variability in breath acetone concentrations (e.g., in response to moderate exercise or altered breathing patterns) can be attributed to airway gas exchange, with minimal changes of the underlying blood and tissue concentrations. Moreover, it is deduced that measured end-tidal breath concentrations of acetone determined during resting conditions and free breathing will be rather poor indicators for endogenous levels. Particularly, the current formulation includes the classical Farhi and the Scheid series inhomogeneity model as special limiting cases.Comment: 38 page

    The role of knowledge management strategies and task knowledge in stimulating service innovation

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    Are service firms that enact strategies to manage their new service development (NSD) knowledge able to generate a sustainable competitive advantage (SCA)? Based on analysis of data from a large survey of service companies, the answer is yes. We find that companies employing the knowledge management strategies of codification and personalization reflect higher levels of NSD knowledge. However, the two strategies vary in their individual performance outcomes, with codification promoting NSD proficiency (an ability to execute NSD activities) and personalization promoting greater NSD innovativeness (market perception of the company as novel and as an innovator). When used together, the two strategies magnify NSD knowledge, which when combined with NSD proficiency and NSD innovativeness, promote a SCA. Therefore, companies planning to invest in a knowledge management system should heed the outcomes desired from their NSD process. A system based on documentation exemplifies a codification strategy and will drive NSD proficiency; a system emphasizing interpersonal communication exemplifies a personalization strategy and will drive NSD innovativeness. A system that blends the two strategies appears the most advantageous for service companies’ NSD efforts aiming to build a long-term sustainable competitive advantage

    The role of mathematical modeling in VOC analysis using isoprene as a prototypic example

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    Isoprene is one of the most abundant endogenous volatile organic compounds (VOCs) contained in human breath and is considered to be a potentially useful biomarker for diagnostic and monitoring purposes. However, neither the exact biochemical origin of isoprene nor its physiological role are understood in sufficient depth, thus hindering the validation of breath isoprene tests in clinical routine. Exhaled isoprene concentrations are reported to change under different clinical and physiological conditions, especially in response to enhanced cardiovascular and respiratory activity. Investigating isoprene exhalation kinetics under dynamical exercise helps to gather the relevant experimental information for understanding the gas exchange phenomena associated with this important VOC. A first model for isoprene in exhaled breath has been developed by our research group. In the present paper, we aim at giving a concise overview of this model and describe its role in providing supportive evidence for a peripheral (extrahepatic) source of isoprene. In this sense, the results presented here may enable a new perspective on the biochemical processes governing isoprene formation in the human body.Comment: 17 page

    IT controls in the public cloud : success factors for allocation of roles and responsibilities

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    The rapid adoption of cloud computing by organizations has resulted in the transformation of the roles and responsibilities of staff in managing the information technology (IT) resources (via IT governance controls) that have migrated to the cloud. Hence, the objective of this research is to provide a set of success factors that can assist IT managers to allocate the roles and responsibilities of IT controls appropriately to staff to manage the migrated IT resources. Accordingly, we generated a set of success factors from behavioral and information systems (IS) literature. These success factors were verified using in-depth interviews of executives from the United Arab Emirates (UAE). The empirical intervention suggests that the role allocation is driven predominantly by people’s skills, competencies, organizational strategy, structures, and policies. In addition, the research made clear that the most significant competency and skill for a person allocated to IT controls is to be able to evaluate and manage a cloud service provider, especially in terms of risks, compliance, and security issues related to public cloud technology. The findings of this study not only offer new insights for scholars and practitioners involved in assigning responsibilities but also provide extensions for IT governance framework authorities to align their guidelines to the emerging cloud technology
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