835 resultados para Change in values


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Aeolian dust (windblown silt and clay) is an important component in arid-land ecosystems because it may contribute to soil formation and furnish essential nutrients. Few geologic surfaces, however, have been characterized with respect to dust-accumulation history and resultant nutrient enrichment. We have developed a combination of methods to identify the presence of aeolian dust in arid regions and to evaluate the roles of this dust in ecosystem processes. Unconsolidated sandy sediment on isolated surfaces in the Canyonlands region of the Colorado Plateau differs greatly in mineralogical and chemical composition from associated bedrock, mainly aeolian sandstone. Detrital magnetite in the surficial deposits produces moderately high values of magnetic susceptibility, but magnetite is absent in nearby bedrock. A component of the surficial deposits must be aeolian to account for the abundance of magnetite, which formed originally in far-distant igneous rocks. Particle-size analysis suggests that the aeolian dust component is typically as much as 20–30%. Dust inputs have enriched the sediments in many elements, including P, Mg, Na, K, and Mo, as well as Ca, at sites where bedrock lacks calcite cement. Soil-surface biologic crusts are effective dust traps that apparently record a change in dust sources over the past several decades. Some of the recently fallen dust may result from human disturbance of land surfaces that are far from the Canyonlands, such as the Mojave Desert. Some land-use practices in the study area have the potential to deplete soil fertility by means of wind-erosion removal of aeolian silt.

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The association between human immunodeficiency virus type I (HIV-1) RNA load changes and the emergence of resistant virus variants was investigated in 24 HIV-1-infected asymptomatic persons during 2 years of treatment with zidovudine by sequentially measuring serum HIV-1 RNA load and the relative amounts of HIV-1 RNA containing mutations at reverse transcriptase (RT) codons 70 (K-->R), 41 (M-->L), and 215 (T-->Y/F). A mean maximum decline in RNA load occurred during the first month, followed by a resurgence between 1 and 3 months, which appeared independent of drug-resistance. Mathematical modeling suggests that this resurgence is caused by host-parasite dynamics, and thus reflects infection of the transiently increased numbers of CD4+ lymphocytes. Between 3 and 6 months of treatment, the RNA load returned to baseline values, which was associated with the emergence of virus containing a single lysine to arginine amino acid change at RT codon 70, only conferring an 8-fold reduction in susceptibility. Despite the relative loss of RNA load suppression, selection toward mutations at RT codons 215 and 41 continued. Identical patterns were observed in the mathematical model. While host-parasite dynamics and outgrowth of low-level resistant virus thus appear responsible for the loss of HIV-1 RNA load suppression, zidovudine continues to select for alternative mutations, conferring increasing levels of resistance.

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A retrospective review was undertaken in 744 patients who were dose-individualized with gentamicin once daily to evaluate a change in gentamicin clearance as a potential predictor of nephrotoxicity. The definition of nephrotoxicity was chosen to be a change in creatinine clearance greater than 20%. Similarly, a change in gentamicin clearance of greater than 20% was also considered a possible index of nephrotoxicity. Four criteria were developed to assess the usefulness of gentamicin clearance as a predictor of nephrotoxicity. Following the application of the inclusion/exclusion criteria, 132 patients were available for the analysis. The sensitivity, specificity, positive predictive value, and negative predictive value were assessed for each of the criteria. Receiver operating characteristic (ROC) curves were produced to determine if an optimum value in the change of gentamicin clearance could be found to maximize sensitivity and specificity. The overall incidence of nephrotoxicity based on a decrease in creatinine clearance by 20% or more was 3.8%. Women were overrepresented in the nephrotoxic group [71.4% versus 40.1% (P = 0.0025)]. Patients with nephrotoxicity had statistically longer treatment periods, increased cumulative dose, and more dosing predictions (P < 0.05 in each case). The sensitivity of the criteria ranged from 43 to 46%, and specificity ranged from 93 to 99%. The positive and negative predictive values ranged from 63 to 94% and 86 to 89%, respectively. In those patients in whom nephrotoxicity was predicted from a change in gentamicin clearance, this change occurred on average 3 days before the change in creatinine clearance (P < 0.05). A change in gentamicin clearance to predict nephrotoxicity may be a useful addition to current monitoring methods, although it is not the complete answer.

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Landscape change occurs through the interaction of a multitude of natural and human driving forces at a range of organisational levels, with humans playing an increasingly dominant role in many regions of the world. Building on the current knowledge of the underlying drivers of landscape change, a conceptual framework of regional landscape change was developed which integrated population, economic and cultural values, policy and science/technology. Using the Southern Brigalow Belt biogeographic region of Queensland as a case study, the role of natural and human drivers in landscape change was investigated in four phases of settlement since 1840. The Brigalow Belt has experienced comparable rates of vegetation clearance over the past 50 years to areas of tropical deforestation. Economic factors were important during all phases of development, but the five regional drivers often acted in synergy. Environmental constraints played a significant role in slowing rates of change. Temporal trends of deforestation followed a sigmoidal curve, with initial slow change accelerating though the middle phases then slowing in recent times. Future landscape management needs to take account of the influence of all the components of the conceptual framework, at a range of organisational levels, if more ecologically sustainable outcomes are to be achieved. (c) 2006 Elsevier B.V. All rights reserved.

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In communities throughout the developing world, faith-based organizations (FBOs) focus on goals such as eradicating poverty, bolstering local economies, and fostering community development, while premising their activities and interaction with local communities on theological and religious understandings. Due to their pervasive interaction with participants, the religious ideologies of these FBOs impact the religious, economic, and social realities of communities. This study investigates the relationship between the international FBO, World Vision International (WVI), and changes to religious, economic, and social ideologies and practices in Andean indigenous communities in southern Peruvian. This study aims to contribute to the greater knowledge and understanding of (1) institutionalized development strategies, (2) faith-based development, and (3) how institutionalized development interacts with processes of socio-cultural change. Based on fifteen months of field research, this study involved qualitative and quantitative methods of participant-observation, interviews, surveys, and document analysis. Data were primarily collected from households from a sample of eight communities in the Pitumarca and Combapata districts, department of Canchis, province of Cusco, Peru where two WVI Area Development Programs were operating. Research findings reveal that there is a relationship between WVI’s intervention and some changes to religious, economic, and social structure (values, ideologies, and norms) and practices, demonstrating that structure and practices change when social systems are altered by new social actors. Findings also revealed that the impacts of WVI’s intervention greatly increased over the course of several years, demonstrating that changes in structure and practice occur gradually and need a period of time to take root. Finally, results showed that the impacts of WVI’s intervention were primarily limited to those most closely involved with the organization, revealing that the ability of one social actor to incite changes in the structure and practice of another actor is associated with the intensity of the relationship between the social actors. The findings of this study should be useful in ascertaining deductions and strengthening understandings of how faith-based development organizations impact aspects of religious, economic, and social life in the areas where they work.

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This thesis investigates the crossover from and intersection between tangible and intangible heritage in the context of World Heritage. Since the start of the twenty-first century, intangible heritage has become increasingly important in international cultural heritage conservation theory and practice. In heritage literature, intangible heritage has been theorized in relation to tangible or built heritage, thereby extending the definition of cultural heritage to consider a holistic perspective. New heritage conservation instruments have been created for the protection of intangible heritage, such as most prominently the 2003 UNESCO Convention for the Safeguarding of the Intangible Cultural Heritage. The changing conception of cultural heritage that goes beyond tangible heritage has also influenced existing instruments like the 1972 UNESCO Convention concerning the protection of the World Cultural and Natural Heritage. The thesis studies how intangible heritage has been recognized and interpreted in implementing the concept of cultural heritage as defined by the World Heritage Convention. It examines the historical development of the concept of World Cultural Heritage with the aim of tracing the construction of intangible heritage in this context. The thesis consists of six chapters. The introduction sets out the research problem and research question. In the literature review, international cultural heritage conservation is portrayed as the research context, the knowledge gap between World Heritage and intangible heritage is identified and an understanding of the research problem deepened, and methods from similar research in the subject area are presented. The methodology in the third chapter describes choices made concerning the research paradigm, research approach and strategy, the use of concepts and illustrative examples, as well as data collection and analysis methods. Knowledge is constructed using primarily a historical approach and related methods. Through the analysis of pertinent documents and heritage discourses, an understanding of the concept of intangible heritage is developed and the concept of World Cultural Heritage is investigated. In the fourth chapter, intangible heritage is studied by looking at specific cultural heritage discourses, that is, a scientific, a UNESCO, and an ICOMOS discourse. Intangible heritage is theorized in relation to the concepts of tangible heritage, heritage value, and cultural heritage. Knowledge gained in this chapter serves as a theoretical lens to trace the recognition of and tease out interpretations of intangible heritage in the context of implementing the concept of World Cultural Heritage. The results are presented in chapter five. A historical development is portrayed in five time periods and for the concepts of cultural heritage, Outstanding Universal Value, the criteria to assess World Heritage value, and authenticity. The conclusion summarizes the main outcomes, assesses the thesis’ contribution to scientific knowledge as well as its limitations, and outlines possible further research. The main results include the identification of the term intangible heritage as an indicator for a paradigm shift and a new approach to conceiving cultural heritage in international cultural heritage conservation. By focusing on processes and the living relationship between people and their environment or place, intangible heritage emphasizes the anthropological. In the context of this conception, intangible heritage takes on two meanings. First, value is attributed by people and hence, is inherently immaterial. Secondly, place is constituted of a tangible-intangible continuum in terms of attributes. A paradigm shift and increasing recognition of an anthropological approach to cultural heritage were identified for all discourses, that is, UNESCO, ICOMOS, the scientific field, and World Heritage. For World Heritage, intangible heritage was recognized indirectly in terms of historical associations during the 1970s and 1980s. The anthropological shift occurred in the early 1990s. The term intangible was introduced and the meaning of intangible heritage was extended to include cultural associations. The subsequent decade is characterized by a process of internalization and implementation of the new approach to cultural heritage. The 2003 Intangible Cultural Heritage Convention created momentum. By the early 2010s, while not explicitly recognizing the immaterial character of values, a holistic approach to cultural heritage was fully endorsed that considers the idea of intangible attributes as carriers of values. An understanding of the recognition of intangible heritage through the implementation of the World Heritage Convention and scientific research in general provide an important knowledge base for implementing the Convention in a more coherent, objective, and well-informed way.

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This thesis investigates the crossover from and intersection between tangible and intangible heritage in the context of World Heritage. Since the start of the twenty-first century, intangible heritage has become increasingly important in international cultural heritage conservation theory and practice. In heritage literature, intangible heritage has been theorized in relation to tangible or built heritage, thereby extending the definition of cultural heritage to consider a holistic perspective. New heritage conservation instruments have been created for the protection of intangible heritage, such as most prominently the 2003 UNESCO Convention for the Safeguarding of the Intangible Cultural Heritage. The changing conception of cultural heritage that goes beyond tangible heritage has also influenced existing instruments like the 1972 UNESCO Convention concerning the protection of the World Cultural and Natural Heritage. The thesis studies how intangible heritage has been recognized and interpreted in implementing the concept of cultural heritage as defined by the World Heritage Convention. It examines the historical development of the concept of World Cultural Heritage with the aim of tracing the construction of intangible heritage in this context. The thesis consists of six chapters. The introduction sets out the research problem and research question. In the literature review, international cultural heritage conservation is portrayed as the research context, the knowledge gap between World Heritage and intangible heritage is identified and an understanding of the research problem deepened, and methods from similar research in the subject area are presented. The methodology in the third chapter describes choices made concerning the research paradigm, research approach and strategy, the use of concepts and illustrative examples, as well as data collection and analysis methods. Knowledge is constructed using primarily a historical approach and related methods. Through the analysis of pertinent documents and heritage discourses, an understanding of the concept of intangible heritage is developed and the concept of World Cultural Heritage is investigated. In the fourth chapter, intangible heritage is studied by looking at specific cultural heritage discourses, that is, a scientific, a UNESCO, and an ICOMOS discourse. Intangible heritage is theorized in relation to the concepts of tangible heritage, heritage value, and cultural heritage. Knowledge gained in this chapter serves as a theoretical lens to trace the recognition of and tease out interpretations of intangible heritage in the context of implementing the concept of World Cultural Heritage. The results are presented in chapter five. A historical development is portrayed in five time periods and for the concepts of cultural heritage, Outstanding Universal Value, the criteria to assess World Heritage value, and authenticity. The conclusion summarizes the main outcomes, assesses the thesis’ contribution to scientific knowledge as well as its limitations, and outlines possible further research. The main results include the identification of the term intangible heritage as an indicator for a paradigm shift and a new approach to conceiving cultural heritage in international cultural heritage conservation. By focusing on processes and the living relationship between people and their environment or place, intangible heritage emphasizes the anthropological. In the context of this conception, intangible heritage takes on two meanings. First, value is attributed by people and hence, is inherently immaterial. Secondly, place is constituted of a tangible-intangible continuum in terms of attributes. A paradigm shift and increasing recognition of an anthropological approach to cultural heritage were identified for all discourses, that is, UNESCO, ICOMOS, the scientific field, and World Heritage. For World Heritage, intangible heritage was recognized indirectly in terms of historical associations during the 1970s and 1980s. The anthropological shift occurred in the early 1990s. The term intangible was introduced and the meaning of intangible heritage was extended to include cultural associations. The subsequent decade is characterized by a process of internalization and implementation of the new approach to cultural heritage. The 2003 Intangible Cultural Heritage Convention created momentum. By the early 2010s, while not explicitly recognizing the immaterial character of values, a holistic approach to cultural heritage was fully endorsed that considers the idea of intangible attributes as carriers of values. An understanding of the recognition of intangible heritage through the implementation of the World Heritage Convention and scientific research in general provide an important knowledge base for implementing the Convention in a more coherent, objective, and well-informed way.

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This data set contains the inputs and the results of the REDD+ Policy Assessment Centre project (REDD-PAC) project (http://www.redd-pac.org), developed by a consortium of research institutes (IIASA, INPE, IPEA, UNEP-WCMC), supported by Germany's International Climate Initiative. Taking a new land use map of Brazil for 2000 as input, the research team used the global economic model GLOBIOM to project land use changes in Brazil up to 2050. Model projections show that Brazil has the potential to balance its goals of protecting the environment and becoming a major global producer of food and biofuels. The model results were taken into account by Brazilian decision-makers when developing the country's intended nationally determined contribution (INDC).

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The recently proposed global monsoon hypothesis interprets monsoon systems as part of one global-scale atmospheric overturning circulation, implying a connection between the regional monsoon systems and an in-phase behaviour of all northern hemispheric monsoons on annual timescales (Trenberth et al., 2000). Whether this concept can be applied to past climates and variability on longer timescales is still under debate, because the monsoon systems exhibit different regional characteristics such as different seasonality (i.e. onset, peak, and withdrawal). To investigate the interconnection of different monsoon systems during the pre-industrial Holocene, five transient global climate model simulations have been analysed with respect to the rainfall trend and variability in different sub-domains of the Afro-Asian monsoon region. Our analysis suggests that on millennial timescales with varying orbital forcing, the monsoons do not behave as a tightly connected global system. According to the models, the Indian and North African monsoons are coupled, showing similar rainfall trend and moderate correlation in rainfall variability in all models. The East Asian monsoon changes independently during the Holocene. The dissimilarities in the seasonality of the monsoon sub-systems lead to a stronger response of the North African and Indian monsoon systems to the Holocene insolation forcing than of the East Asian monsoon and affect the seasonal distribution of Holocene rainfall variations. Within the Indian and North African monsoon domain, precipitation solely changes during the summer months, showing a decreasing Holocene precipitation trend. In the East Asian monsoon region, the precipitation signal is determined by an increasing precipitation trend during spring and a decreasing precipitation change during summer, partly balancing each other. A synthesis of reconstructions and the model results do not reveal an impact of the different seasonality on the timing of the Holocene rainfall optimum in the different sub-monsoon systems. They rather indicate locally inhomogeneous rainfall changes and show, that single palaeo-records should not be used to characterise the rainfall change and monsoon evolution for entire monsoon sub-systems.

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Secular trends in height and weight are reasonably well documented in Europe. Corresponding observations for skeletal maturation are lacking. Aim: To assess secular trends in height, body mass and skeletal maturity of Portuguese children and adolescents and to provide updated reference values for skeletal maturity scores (SMSs). Subjects and methods: Data for 2856 children and adolescents of 4–17 years, 1412 boys and 1444 girls, from The ‘Madeira Growth Study’ (MGS; 1996–1998) and from the‘Healthy Growth of Madeira Children Study’ (CRES; 2006) were used. Height and body mass were measured. Skeletal maturity was assessed with the Tanner-Whitehouse 2 and 3 methods. Results: Children from CRES were taller and heavier than peers from MGS. Differences in height reached 5.8cm in boys and 5.5cm in girls. RUS SMSs did not differ consistently between surveys boys, while higher RUS scores were observed in CRES girls. Adult RUS SMSs for MGS and CRES combined were attained at 15.8 years in boys and 14.8 years in girls. Corresponding ages for adult Carpal SMSs were 14.4 and 14.0, respectively. Conclusion: The short-term trends for height and mass were not entirely consistent with the trends in RUS and Carpal SMSs and SAs.

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Community development is centrally concerned with people in communities working together to achieve a common goal, that is, to collaborate, whether within local geographical communities, in communities of shared interests or among groups sharing a common identity. Its overarching goal is one of progressive transformational social change. As Belfast transitions from a conflict to a post-conflict society, there is a need for greater, more effective work at local community level in order to address a range of ongoing social and economic issues facing communities, including high levels of disadvantage and division. Given the significance of leadership in building effective collaboration and the centrality of collaboration for community development, it is important to understand how leadership is currently enacted and what kinds of leadership are required to support communities to collaborate effectively to bring about social change. This thesis thus centers on the kind of leadership practised and required to support collaboration for social change within the community sector in Belfast, a city that contains an estimated 28% of the total number of community and voluntary sector (CVS) organisations in Northern Ireland (Northern Ireland Council for Voluntary Action, 2012). Through a series of qualitative, in-depth interviews with people playing leadership roles in local communities, the study critically explores and analyses their experiences and perceptions in relation to leadership and collaboration. Community development in Belfast today is practised within a wider context of neoliberal policies, characterised by austerity and public spending cuts. Whilst not the only influencing factor, this context has had a particular and profound impact on the nature and role of community development practised, and on the kind of leadership enacted within it. The space for reflection and transformative action appears to be shrinking as the contraction of resources to support community development in local communities continues unabated. Those playing leadership roles increasingly find themselves compelled to spend time seeking resources and managing complex funding arrangements rather than focusing on the social change dimensions of their work. Collaboration as promoted by the state seems to have become an instrumental tactic used to implement its austerity measures and curtail the potential of the community sector. Despite this, local leaders are driving initiatives that attempt to push back, helping the sector refocus on its transformational goals of social change. To do this requires support. Those playing leadership roles require resources, including time, to encourage and enable communities to reconnect with the purpose and underpinning values of community development. Leaders also need support to develop and promote new, progressive narratives and visions and pursue these through building collaboration and solidarity.

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Secular trends in height and weight are reasonably well documented in Europe. Corresponding observations for skeletal maturation are lacking. Aim: To assess secular trends in height, body mass and skeletal maturity of Portuguese children and adolescents and to provide updated reference values for skeletal maturity scores (SMSs). Subjects and methods: Data for 2856 children and adolescents of 4–17 years, 1412 boys and 1444 girls, from The ‘Madeira Growth Study’ (MGS; 1996–1998) and from the‘Healthy Growth of Madeira Children Study’ (CRES; 2006) were used. Height and body mass were measured. Skeletal maturity was assessed with the Tanner-Whitehouse 2 and 3 methods. Results: Children from CRES were taller and heavier than peers from MGS. Differences in height reached 5.8cm in boys and 5.5cm in girls. RUS SMSs did not differ consistently between surveys boys, while higher RUS scores were observed in CRES girls. Adult RUS SMSs for MGS and CRES combined were attained at 15.8 years in boys and 14.8 years in girls. Corresponding ages for adult Carpal SMSs were 14.4 and 14.0, respectively. Conclusion: The short-term trends for height and mass were not entirely consistent with the trends in RUS and Carpal SMSs and SAs.