863 resultados para multi-attribute analysis


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The link between the atmospheric CO2 level and the ventilation state of the deep ocean is an important building block of the key hypotheses put forth to explain glacial-interglacial CO2 fluctuations. In this study, we systematically examine the sensitivity of atmospheric CO2 and its carbon isotope composition to changes in deep ocean ventilation, the ocean carbon pumps, and sediment formation in a global three-dimensional ocean-sediment carbon cycle model. Our results provide support for the hypothesis that a break up of Southern Ocean stratification and invigorated deep ocean ventilation were the dominant drivers for the early deglacial CO2 rise of ~35 ppm between the Last Glacial Maximum and 14.6 ka BP. Another rise of 10 ppm until the end of the Holocene is attributed to carbonate compensation responding to the early deglacial change in ocean circulation. Our reasoning is based on a multi-proxy analysis which indicates that an acceleration of deep ocean ventilation during the early deglaciation is not only consistent with recorded atmospheric CO2 but also with the reconstructed opal sedimentation peak in the Southern Ocean at around 16 ka BP, the record of atmospheric δ13CCO2, and the reconstructed changes in the Pacific CaCO3 saturation horizon.

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The link between the atmospheric CO2 level and the ventilation state of the deep ocean is an important building block of the key hypotheses put forth to explain glacial-interglacial CO2 fluctuations. In this study, we systematically examine the sensitivity of atmospheric CO2 and its carbon isotope composition to changes in deep ocean ventilation, the ocean carbon pumps, and sediment formation in a global 3-D ocean-sediment carbon cycle model. Our results provide support for the hypothesis that a break up of Southern Ocean stratification and invigorated deep ocean ventilation were the dominant drivers for the early deglacial CO2 rise of ~35 ppm between the Last Glacial Maximum and 14.6 ka BP. Another rise of 10 ppm until the end of the Holocene is attributed to carbonate compensation responding to the early deglacial change in ocean circulation. Our reasoning is based on a multi-proxy analysis which indicates that an acceleration of deep ocean ventilation during early deglaciation is not only consistent with recorded atmospheric CO2 but also with the reconstructed opal sedimentation peak in the Southern Ocean at around 16 ka BP, the record of atmospheric δ13CCO2, and the reconstructed changes in the Pacific CaCO3 saturation horizon.

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OBJECTIVES: The aim of this study is to assess the structural and cross-cultural validity of the KIDSCREEN-27 questionnaire. METHODS: The 27-item version of the KIDSCREEN instrument was derived from a longer 52-item version and was administered to young people aged 8-18 years in 13 European countries in a cross-sectional survey. Structural and cross-cultural validity were tested using multitrait multi-item analysis, exploratory and confirmatory factor analysis, and Rasch analyses. Zumbo's logistic regression method was applied to assess differential item functioning (DIF) across countries. Reliability was assessed using Cronbach's alpha. RESULTS: Responses were obtained from n = 22,827 respondents (response rate 68.9%). For the combined sample from all countries, exploratory factor analysis with procrustean rotations revealed a five-factor structure which explained 56.9% of the variance. Confirmatory factor analysis indicated an acceptable model fit (RMSEA = 0.068, CFI = 0.960). The unidimensionality of all dimensions was confirmed (INFIT: 0.81-1.15). Differential item functioning (DIF) results across the 13 countries showed that 5 items presented uniform DIF whereas 10 displayed non-uniform DIF. Reliability was acceptable (Cronbach's alpha = 0.78-0.84 for individual dimensions). CONCLUSIONS: There was substantial evidence for the cross-cultural equivalence of the KIDSCREEN-27 across the countries studied and the factor structure was highly replicable in individual countries. Further research is needed to correct scores based on DIF results. The KIDSCREEN-27 is a new short and promising tool for use in clinical and epidemiological studies.

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Can one observe an increasing level of individual lack of orientation because of rapid social change in modern societies? This question is examined using data from a representative longitudinal survey in Germany conducted in 2002–04. The study examines the role of education, age, sex, region (east/west), and political orientation for the explanation of anomia and its development. First we present the different sources of anomie in modern societies, based on the theoretical foundations of Durkheim and Merton, and introduce the different definitions of anomia, including our own cognitive version. Then we deduce several hypotheses from the theory, which we test by means of longitudinal data for the period 2002–04 in Germany using the latent growth curve model as our statistical method. The empirical findings show that all the sociodemographic variables, including political orientation, are strong predictors of the initial level of anomia. Regarding the development of anomia over time (2002–04), only the region (west) has a significant impact. In particular, the results of a multi-group analysis show that western German people with a right-wing political orientation become more anomic over this period. The article concludes with some theoretical implications.

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Recent evidence suggests that managers establish a positive link between management accounting system (MAS) integration and controllership effectiveness, which is fully mediated by the perceived consistency of financial language. Our paper extends this research by analyzing whether controllers have similar perceptions on MAS design. Testing a series of multi-group structural equation models, we find evidence for a preparer-user perception gap with respect to the mediating impact of a consistent financial language. Our results contribute to the still-ongoing controversial debate on MAS integration by indicating that the effectiveness of MAS design cannot be evaluated solely from an instrumental perspective independent from users’ perceptions.

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The objective of this paper is to discuss EU lobbying in the area of copyright. Legislation needs to regulate the legal position of various different stakeholders in a balanced manner. However, a number of EU copyright provisions brought into effect over recent years were highly controversial and have led to suggestions that powerful lobbying forces may have had some influence. This article investigates the effects of lobbying on copyright law-making in Europe. A specific comparative and multi-faceted analysis is provided of the legislative process for two recently adopted directives: 2011/77/EU which extends the term of protection of sound recordings and 2012/28/EU which introduces certain permitted uses of orphan works (some references are also made to the ACTA case). Firstly, a short presentation is given of the legal bases for the EU consultation process and lobbying. Next, an analysis is provided of the two cases, taking into consideration the policy-making procedures (with special focus on how the consultation process was handled), the legal solutions proposed and adopted and the various stakeholders’ claims. Lastly, it asks why some interest groups were successful and some others failed (the analysis identifies two types of factor for the effectiveness of lobbying: those resulting from stakeholders’ actions and those connected with the consultation process).

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Changes in agricultural practices of semi-natural mountain grasslands are expected to modify plant community structure and shift dominance patterns. Using vegetation surveys of 11 sites in semi-natural grasslands of the Swiss Jura and Swiss and French Alps, we determined the relative contribution of dominant, subordinate and transient plant species in grazed and abandoned communities and observed their changes along a gradient of productivity and in response to abandonment of pasturing. The results confirm the humpbacked diversity–productivity relationship in semi-natural grassland, which is due to the increase of subordinate species number at intermediate productivity levels. Grazed communities, at the lower or higher end of the species diversity gradient, suffered higher species loss after grazing abandonment. Species loss after abandonment of pasturing was mainly due to a higher reduction in the number of subordinate species, as a consequence of the increasing proportion of dominant species. When plant biodiversity maintenance is the aim, our results have direct implications for the way grasslands should be managed. Indeed, while intensification and abandonment have been accelerated since few decades, our findings in this multi-site analysis confirm the importance of maintaining intermediate levels of pasturing to preserve biodiversity.

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Volunteering rates in Switzerland vary substantially across language regions. In this article, we investigate the cultural roots of this variation by presenting and empirically testing two different conceptualizations of how linguistic culture is related to individual volunteering. Whereas the first perspective perceives the individual as belonging to a particular language community and its norms and values as crucial for individual volunteering, the other sees the linguistic culture mainly as an important context in which an individual lives and which therefore influences individual volunteering. Empirically, we base our analysis on new survey data from 60 Swiss communes and apply a Bayesian multi-level analysis in order to disentangle the linguistic group from contextual effects. Our analysis supports the view that cultural patterns of civic self-organization can indeed explain regional volunteering behaviour in Switzerland. Whereas the propensity to volunteer is generally highest in German-speaking Switzerland, our findings reveal that it is the group of French speakers that exhibits the highest propensity to volunteer when controlling for language region.

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Social Networking Sites (SNSs) have become extremely popular around the world. They rely on user-generated content to offer engaging experience to its members. Cultural differences may influence the motivation of users to create and share content on SNS. This study adopts the privacy calculus perspective to examine the role of culture in individual self-disclosure decisions. The authors use structural equation modeling and multi-group analysis to investigate this dynamics. The findings reveal the importance of cultural dimensions of individualism and uncertainty avoidance in the cognitive processes of SNS users.

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The significance of the multi-isotopic record preserved in K-feldspars is assessed on samples from the Aar metagranite, Central Alps, Switzerland having very tight independent geological constraints. Stepwise leaching reveals that two diachronically grown K-feldspar generations coexist: Kfs-1 (≥ 35 Ma old, Ca-poor, Rb-Cl-rich, with low 87Sr/86Sr and high 206Pb/204Pb) and Kfs-2 (≤ 10 Ma old, antithetic isotopic signatures deriving from external fluids). Microtextures imaged by cathodoluminescence, backscattered electrons, and electron probe microanalysis are patchy and chemically heterogeneous, with pronounced enrichments in Ba in the retrogressed regions. This confirms the simultaneous presence of fluid-dominated retrogression and recrystallization and isotopic inheritance. The staircase-shaped 40Ar/39Ar age spectrum correlates with the Ca/K and Cl/K signatures. This reflects a mixture of heterochemical K-feldspar generations, and not an intracrystalline Ar gradient caused by diffusion. The shape of the age spectrum and the in vacuo release kinetics proceed from entirely different physical and geological phenomena. What K-feldspars can be effectively used for is to constrain the timing of the fluids that interacted with them by multi-isotopic analyses, rather than to model a “cooling history” from 39Ar release alone. The identification of multiple mineral generations by imaging combined with multi-isotopic analysis enables the accurate dating of the events of a multistage evolution after the initial crystallization of the rock in which the minerals occur.

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As social networking sites (SNSs) become increasingly global, the issues of cultural differences in participation patterns become acute. However, current research offers only limited insights into the role of culture behind SNS usage. Aiming to fill this gap, this study adopts a ‘privacy calculus’ perspective to study the differences between German and American SNS users. Results of structural equation modeling and multi-group analysis reveal distinct variability in the cognitive patterns of American and German subjects. We contribute to the theory by rejecting the universal nature of privacy-calculus processes. From a practical standpoint, our results signal that SNS providers cannot rely on the “proven” means in ensuring user participation when crossing geographic boundaries. When financial means are limited, SNS providers should direct their investments into enhancing platform enjoyment and granting users with more control and, paradoxically, lobbying for more legalistic safeguards of user privacy.

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INTRODUCTION Anemia and renal impairment are important co-morbidities among patients with coronary artery disease undergoing Percutaneous Coronary Intervention (PCI). Disease progression to eventual death can be understood as the combined effect of baseline characteristics and intermediate outcomes. METHODS Using data from a prospective cohort study, we investigated clinical pathways reflecting the transitions from PCI through intermediate ischemic or hemorrhagic events to all-cause mortality in a multi-state analysis as a function of anemia (hemoglobin concentration <120 g/l and <130 g/l, for women and men, respectively) and renal impairment (creatinine clearance <60 ml/min) at baseline. RESULTS Among 6029 patients undergoing PCI, anemia and renal impairment were observed isolated or in combination in 990 (16.4%), 384 (6.4%), and 309 (5.1%) patients, respectively. The most frequent transition was from PCI to death (6.7%, 95% CI 6.1-7.3), followed by ischemic events (4.8%, 95 CI 4.3-5.4) and bleeding (3.4%, 95% CI 3.0-3.9). Among patients with both anemia and renal impairment, the risk of death was increased 4-fold as compared to the reference group (HR 3.9, 95% CI 2.9-5.4) and roughly doubled as compared to patients with either anemia (HR 1.7, 95% CI 1.3-2.2) or renal impairment (HR 2.1, 95% CI 1.5-2.9) alone. Hazard ratios indicated an increased risk of bleeding in all three groups compared to patients with neither anemia nor renal impairment. CONCLUSIONS Applying a multi-state model we found evidence for a gradient of risk for the composite of bleeding, ischemic events, or death as a function of hemoglobin value and estimated glomerular filtration rate at baseline.

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Introduction: Over the last decades, Swiss sports clubs have lost their "monopoly" in the market for sports-related services and increasingly are in competition with other sports providers. For many sport clubs long-term membership cannot be seen as a matter of course. Current research on sports clubs in Switzerland – as well as for other European countries – confirms the increasing difficulties in achieving long-term member commitment. Looking at recent findings of the Swiss sport clubs report (Lamprecht, Fischer & Stamm, 2012), it can be noted, that a decrease in memberships does not equally affect all clubs. There are sports clubs – because of their specific situational and structural conditions – that have few problems with member fluctuation, while other clubs show considerable declines in membership. Therefore, a clear understanding of individual and structural factors that trigger and sustain member commitment would help sports clubs to tackle this problem more effectively. This situation poses the question: What are the individual and structural determinants that influence the tendency to continue or to quit the membership? Methods: Existing research has extensively investigated the drivers of members’ commitment at an individual level. As commitment of members usually occurs within an organizational context, the characteristics of the organisation should be also considered. However, this context has been largely neglected in current research. This presentation addresses both the individual characteristics of members and the corresponding structural conditions of sports clubs resulting in a multi-level framework for the investigation of the factors of members’ commitment in sports clubs. The multilevel analysis grant a adequate handling of hierarchically structured data (e.g., Hox, 2002). The influences of both the individual and context level on the stability of memberships are estimated in multi-level models based on a sample of n = 1,434 sport club members from 36 sports clubs. Results: Results of these multi-level analyses indicate that commitment of members is not just an outcome of individual characteristics, such as strong identification with the club, positively perceived communication and cooperation, satisfaction with sports clubs’ offers, or voluntary engagement. It is also influenced by club-specific structural conditions: stable memberships are more probable in rural sports clubs, and in clubs that explicitly support sociability, whereas sporting-success oriented goals in clubs have a destabilizing effect. Discussion/Conclusion: The proposed multi-level framework and the multi-level analysis can open new perspectives for research concerning commitment of members to sports clubs and other topics and problems of sport organisation research, especially in assisting to understand individual behavior within organizational contexts. References: Hox, J. J. (2002). Multilevel analysis: Techniques and applications. Mahwah: Lawrence Erlbaum. Lamprecht, M., Fischer, A., & Stamm, H.-P. (2012). Die Schweizer Sportvereine – Strukturen, Leistungen, Herausforderungen. Zurich: Seismo.

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Lake Butrint (39°47 N, 20°1 E) is a ca. 21 m deep, coastal lagoon located in SW Albania where finely-laminated sediments have been continuously deposited during the last millennia. The multi-proxy analysis (sedimentology, high-resolution elemental geochemistry and pollen) of a 12 m long sediment core, supported by seven AMS radiocarbon dates and 137Cs dating, enable a precise reconstruction of the environmental change that occurred in the central Mediterranean region during the last ∼4.5 cal kyrs BP. Sediments consist of triplets of authigenic carbonates, organic matter and clayey laminae. Fluctuations in the thickness and/or presence of these different types of seasonal laminae indicate variations in water salinity, organic productivity and runoff in the lake's catchment, as a result of the complex interplay of tectonics, anthropogenic forcing and climate variability. The progradation of the Pavllo river delta, favoured by variable human activity from the nearby ancient city of Butrint, led to the progressive isolation of this hydrological system from the Ionian Sea. The system evolved from an open bay to a restricted lagoon, which is consistent with archaeological data. An abrupt increase in mass-wasting activity between 1515 and 1450 BC, likely caused by nearby seismic activity, led to the accumulation of 24 homogenites, up to 17 cm thick. They have been deposited during the onset of finely laminated sedimentation, which indicates restricted, anoxic bottom water conditions and higher salinity. Periods of maximum water salinity, biological productivity, and carbonate precipitation coincide with warmer intervals, such as the early Roman Warm Period (RWP) (500 BC–0 AD), the Medieval Climate Anomaly (MCA) (800–1400 AD) and recent times (after 1800 AD). Conversely, lower salinity and more oxic conditions, with higher clastic input were recorded during 1400–500 BC, the Late Roman and the Early Medieval periods (0–800 AD) and during the Little Ice Age (1400–1800 AD). Hydrological fluctuations recorded in Butrint are in phase with most central and western Mediterranean records and correlate with NAO variability. In contrast, opposite hydrological patterns have been recorded in the Eastern Balkans and the Levant during the last millennium, emphasizing a complex spatial variability in the region. Phases of maximum settlement intensity in Butrint (Roman-Late Antique) coincide with warmer and/or stable climate periods (0–800 AD and MCA, respectively), indicating a long-term influence of climatic conditions on human activities. The Late Holocene sedimentary record of Lake Butrint demonstrates the complex interplay of climate variability, tectonics and human impact in the recent evolution of coastal Mediterranean regions.

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Inductively coupled plasma mass spectrometry (ICP-MS) is a suitable tool for multi-element analysis at low concentration levels. Rare earth element (REE) determinations in standard reference materials and small volumes of molten ice core samples from Antarctica have been performed with an ICP-time of flight-MS (ICP-TOF-MS) system. Recovery rates for REE in e.g. SPS-SW1 amounted to not, vert, similar ~103%, and the relative standard deviations were 3.4% for replicate analysis at REE concentrations in the lower ng/l range. Analyses of REE concentrations in Antarctic ice core samples showed that the ICP-TOF-MS technique meets the demands of restricted sample mass. The data obtained are in good agreement with ICP-Quadrupole-MS (ICP-Q-MS) and ICP-Sector Field-MS (ICP-SF-MS) results. The ICP-TOF-MS system determines accurately and precisely REE concentrations exceeding 5 ng/l while between 0.5 and 5 ng/l accuracy and precision are element dependent.