920 resultados para multiple change-points
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The purpose of this study was to evaluate longitudinally, using the Iowa Gambling Task (IGT), the dynamics of decision-making capacity at a two-year interval (median: 2.1 years) in a group of patients with multiple sclerosis (MS) (n = 70) and minor neurological disability [Expanded Disability Status Scale (EDSS) < or = 2.5 at baseline]. Cognition (memory, executive functions, attention), behavior, handicap, and perceived health status were also investigated. Standardized change scores [(score at retest-score at baseline)/standard deviation of baseline score] were computed. Results showed that IGT performances decreased from baseline to retest (from 0.3, SD = 0.4 to 0.1, SD = 0.3, p = .005). MS patients who worsened in the IGT were more likely to show a decreased perceived health status and emotional well-being (SEP-59; p = .05 for both). Relapsing rate, disability progression, cognitive, and behavioral changes were not associated with decreased IGT performances. In conclusion, decline in decision making can appear as an isolated deficit in MS.
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Geometries, vibrational frequencies, and interaction energies of the CNH⋯O3 and HCCH⋯O3 complexes are calculated in a counterpoise-corrected (CP-corrected) potential-energy surface (PES) that corrects for the basis set superposition error (BSSE). Ab initio calculations are performed at the Hartree-Fock (HF) and second-order Møller-Plesset (MP2) levels, using the 6-31G(d,p) and D95++(d,p) basis sets. Interaction energies are presented including corrections for zero-point vibrational energy (ZPVE) and thermal correction to enthalpy at 298 K. The CP-corrected and conventional PES are compared; the unconnected PES obtained using the larger basis set including diffuse functions exhibits a double well shape, whereas use of the 6-31G(d,p) basis set leads to a flat single-well profile. The CP-corrected PES has always a multiple-well shape. In particular, it is shown that the CP-corrected PES using the smaller basis set is qualitatively analogous to that obtained with the larger basis sets, so the CP method becomes useful to correctly describe large systems, where the use of small basis sets may be necessary
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Mountains and mountain societies provide a wide range of goods and services to humanity, but they are particularly sensitive to the effects of global environmental change. Thus, the definition of appropriate management regimes that maintain the multiple functions of mountain regions in a time of greatly changing climatic, economic, and societal drivers constitutes a significant challenge. Management decisions must be based on a sound understanding of the future dynamics of these systems. The present article reviews the elements required for an integrated effort to project the impacts of global change on mountain regions, and recommends tools that can be used at 3 scientific levels (essential, improved, and optimum). The proposed strategy is evaluated with respect to UNESCO's network of Mountain Biosphere Reserves (MBRs), with the intention of implementing it in other mountain regions as well. First, methods for generating scenarios of key drivers of global change are reviewed, including land use/land cover and climate change. This is followed by a brief review of the models available for projecting the impacts of these scenarios on (1) cryospheric systems, (2) ecosystem structure and diversity, and (3) ecosystem functions such as carbon and water relations. Finally, the cross-cutting role of remote sensing techniques is evaluated with respect to both monitoring and modeling efforts. We conclude that a broad range of techniques is available for both scenario generation and impact assessments, many of which can be implemented without much capacity building across many or even most MBRs. However, to foster implementation of the proposed strategy, further efforts are required to establish partnerships between scientists and resource managers in mountain areas.
Upgrading or polarization? occupational change in Britain, Germany, Spain and Switzerland, 1990-2008
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This paper analyzes the pattern of occupational change in four Western European countries over the last two decades: what kind of jobs have been expanding -- high-paid jobs, low-paid jobs or both? By addressing this issue, we also examine what theoretical account is consistent with the observed pattern of change: skill-biased technical change, skill supply evolution or wage-setting institutions? Our empirical findings show a picture of massive occupational upgrading that closely matches educational expansion. In all four countries, by far the strongest employment growth occurred at the top of the occupational hierarchy, among managers and professionals. Yet in parallel, in Britain and Switzerland, as well as in Germany and Spain after 1996 and 2002 respectively, relative employment declined more strongly in the middling occupations (among clerks and production workers) than at the bottom (among interpersonal service workers). This slightly polarized pattern of occupational upgrading is consistent with the "routinization" hypothesis that technology is a better substitute for average-paid jobs in production and the office that for low-paid jobs in interpersonal services. However, we find large cross-country differences in the employment evolution at the bottom of the occupational hierarchy, among low-paid services workers: sizeable growth in Britain and Spain, but stagnation in Germany and Switzerland. This results points towards the possibility that wage-setting institutions filter the pattern of occupational change.
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Biological reference points are important tools for fisheries management. Reference points are not static, but may change when a population's environment or the population itself changes. Fisheries-induced evolution is one mechanism that can alter population characteristics, leading to "shifting" reference points by modifying the underlying biological processes or by changing the perception of a fishery system. The former causes changes in "true" reference points, whereas the latter is caused by changes in the yardsticks used to quantify a system's status. Unaccounted shifts of either kind imply that reference points gradually lose their intended meaning. This can lead to increased precaution, which is safe, but potentially costly. Shifts can also occur in more perilous directions, such that actual risks are greater than anticipated. Our qualitative analysis suggests that all commonly used reference points are susceptible to shifting through fisheries-induced evolution, including the limit and "precautionary" reference points for spawning-stock biomass, Blim and Bpa, and the target reference point for fishing mortality, F0.1. Our findings call for increased awareness of fisheries-induced changes and highlight the value of always basing reference points on adequately updated information, to capture all changes in the biological processes that drive fish population dynamics.
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This final project was made for the Broadband/Implementation department of TeliaSonera Finland. The question to be examined is if the operator should replace multiple ADSL connections implemented over a leased line with Multi-Dwelling access based on an Ethernet/Optical Fibre access network. The project starts with describing the technology related to these access network solu-tions and presents the technology that is used in TeliaSonera Finland's access network. It continues from the technology to describe the problem with some of the ADSL implemen-tations of TeliaSonera. The problem is the implementations done over a leased line that can cost TeliaSonera over years as much as a possible investment to extend network when there is several lines leased to the same building. The project proposes a Multi-Dwelling access as a solution to this problem and defines the circumstances when to use it. After a satisfactory solution has found the project takes a view how implementation of the solution might alter the network and a new problem is found. When used commonly to replace need of ADSL implementation Multi-Dwelling access would significantly increase optical cable congestion near operators POP. As a final deed this project also proposes a technical change to existing way to implement multi-dwelling access with EPON technology.
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Résumé Les champignons endomycorhiziens arbusculaires (CEA) forment des symbioses avec la plupart des plantes terrestres. Les CEA influencent la croissance des plantes et la biodiversité. Ils sont supposés avoir évolué de manière asexuée pendant au moins 400 millions d'années et aucune diversification morphologique majeure n'a été constatée. Pour ces raisons, les CEA sont considérés comme d'anciens asexués. Très peu d'espèces sont connues actuellement. Les individus de ces champignons contiennent des noyaux génétiquement différents dans un cytoplasme continu. La signification évolutive, la variabilité et la maintenance des génomes multiples au sein des individus sont inconnues. Ce travail a démontré qu'une population du CEA Glomus intraradices est génétiquement très variable. Nous avons conclu que les plantes hôtes plutôt que la différenciation géographique devraient être responsables de cette grande diversité. Puis nous avons cherché l'existence de recombinaison entre génotypes dans une population. Nous avons détecté un groupe recombinant au sein de la population, ce qui met en doute l'état d'anciens asexués des CEA. Nous avons également détecté l'occurrence de fusions d'hyphes et l'échange de noyaux entre isolats génétiquement différents. La descendance hybride issue de cet échange était viable et distincte phénotypiquement des isolats parentaux. En résumé, ce travail identifie des événements cruciaux dans le cycle de vie des CEA qui ont le potentiel d'influencer l'évolution de génomes multiples. L'étude des conséquences de ces événements sur les interactions avec les plantes hôtes pourrait éclaircir significativement la compréhension de la symbiose entre plantes et CEA. Abstract Arbuscular mycorrhizal fungi (AMF) are important symbionts of most land plants. AMF influence plant growth and biodiversity. Very few extant species are described. AMF are thought to have evolved asexually for at least 400 million years and no major morphological diversification has occurred. Due to these reasons, they were termed `ancient asexuals'. Fungal individuals harbour genetically different nuclei in a continuous cytoplasm. The variability, maintenance and evolutionary significance of multiple genomes within individuals are unknown. This work showed that a population of the AMF Glomus intraradices harbours very high genetic diversity. We concluded that host plants rather than geographic differentiation were responsible for this diversity. Furthermore, we investigated whether recombination occurred among genotypes of a G. intraradices population. The identification of a core group of recombining genotypes in the population refutes the assumption of ancient asexuality in AMF. We found that genetically different isolates can form hyphal fusions and exchange nuclei. The hybrid progeny produced by the exchange was viable and phenotypically distinct from the parental isolates. Taken together, this work provided evidence for key events in the AMF life cycle, that influence the evolution of multiple genomes. Studying the consequences of these events on the interaction with host plants may significantly further the understanding of the AMF-plant symbiosis.
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The generalization of simple correspondence analysis, for two categorical variables, to multiple correspondence analysis where they may be three or more variables, is not straighforward, both from a mathematical and computational point of view. In this paper we detail the exact computational steps involved in performing a multiple correspondence analysis, including the special aspects of adjusting the principal inertias to correct the percentages of inertia, supplementary points and subset analysis. Furthermore, we give the algorithm for joint correspondence analysis where the cross-tabulations of all unique pairs of variables are analysed jointly. The code in the R language for every step of the computations is given, as well as the results of each computation.
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In the analysis of multivariate categorical data, typically the analysis of questionnaire data, it is often advantageous, for substantive and technical reasons, to analyse a subset of response categories. In multiple correspondence analysis, where each category is coded as a column of an indicator matrix or row and column of Burt matrix, it is not correct to simply analyse the corresponding submatrix of data, since the whole geometric structure is different for the submatrix . A simple modification of the correspondence analysis algorithm allows the overall geometric structure of the complete data set to be retained while calculating the solution for the selected subset of points. This strategy is useful for analysing patterns of response amongst any subset of categories and relating these patterns to demographic factors, especially for studying patterns of particular responses such as missing and neutral responses. The methodology is illustrated using data from the International Social Survey Program on Family and Changing Gender Roles in 1994.
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Purpose of the evaluation This is a scheduled standard mid-term evaluation (MTR) of a UNDP implemented GEF LDCF co-financed project. It is conducted by a team of an international and a national independent evaluator. The objective of the MTR, as set out in the Terms of Reference (TORs; Annex 1), is to provide an independent analysis of the progress of the project so far. The MTR aims to: identify potential project design problems, assess progress towards the achievement of the project objective and outcomes, identify and document lessons learned (including lessons that might improve design and implementation of other projects, including UNDP-GEF supported projects), and make recommendations regarding specific actions that should be taken to improve the project. The MTR is intended to assess signs of project success or failure and identify the necessary changes to be made. The project commenced its implementation in the first half of 2010 with the recruitment of project staff. According to the updated project plan, it is due to close in July 201410 with operations scaling down in December 2013 due to funding limits. Because of a slow implementation start, the mid-term evaluation was delayed to July 201311 The intended target audience of the evaluation are: The project team and decision makers in the INGRH The GEF and UNFCCC Operational Focal Points The project partners and beneficiaries UNDP in Cape Verde as well as the regional and headquarter (HQ) office levels The GEF Secretariat.
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On April 27, 2007, Iowa Governor Chet Culver signed Senate File 485, a bill related to greenhouse gas emissions. Part of this bill created the Iowa Climate Change Advisory Council (ICCAC), which consists of 23 governor-appointed members from various stakeholder groups, and 4 nonvoting, ex officio members from the General Assembly. ICCAC’s immediate responsibilities included submitting a proposal to the Governor and General Assembly that addresses policies, cost-effective strategies, and multiple scenarios designed to reduce statewide greenhouse gas emissions. Further, a preliminary report was submitted in January 2008, with a final proposal submitted in December 2008. In the Final Report, the Council presents two scenarios designed to reduce statewide greenhouse gas emissions by 50% and 90% from a 2005 baseline by the year 2050. For the 50% reduction by 2050, the Council recommends approximately a 1% reduction by 2012 and an 11% reduction by 2020. For the 90% reduction scenario, the Council recommends a 3% reduction by 2012 and a 22% reduction 2020. These interim targets were based on a simple extrapolation assuming a linear rate of reduction between now and 2050. In providing these scenarios for your consideration, ICCAC approved 56 policy options from a large number of possibilities. There are more than enough options to reach the interim and final emission targets in both the 50% and 90% reduction scenarios. Direct costs and cost savings of these policy options were also evaluated with the help of The Center for Climate Strategies, who facilitated the process and provided technical assistance throughout the entire process, and who developed the Iowa Greenhouse Gas Emissions Inventory and Forecast in close consultation with the Iowa Department of Natural Resources (IDNR) and many Council and Sub-Committee members. About half of the policy options presented in this report will not only reduce GHG emissions but are highly cost-effective and will save Iowans money. Still other options may require significant investment but will create jobs, stimulate energy independence, and advance future regional or federal GHG programs.
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Objective The aim is to analyze and compare individual BMI growth patterns of adults from Switzerland and the U.S. Methods The analyses are based on data from two population representative longitudinal household surveys, one from Switzerland, the other from the U.S. Each data set contains up to four data points for each adult individual. We use multilevel models for growth. Results It can be shown that growth patterns are different in different cohorts in the two countries: there are only small growth differences in the youngest and oldest, but large differences in the middle ages. The individual BMI increase of the middle age Swiss amounts to only half of that in the comparable U.S. individuals. Conclusion Given the much higher BMI level especially in the youngest cohort, this points to severe obesity problems in the U.S. middle aged population in the near future. A positive correlation between individual BMI level and growth may aggravate this fact.
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Introduction: The Thalidomide-Dexamethasone (TD) regimen has provided encouraging results in relapsed MM. To improve results, bortezomib (Velcade) has been added to the combination in previous phase II studies, the so called VTD regimen. In January 2006, the European Group for Blood and Marrow Transplantation (EBMT) and the Intergroupe Francophone du Myélome (IFM) initiated a prospective, randomized, parallel-group, open-label phase III, multicenter study, comparing VTD (arm A) with TD (arm B) for MM patients progressing or relapsing after autologous transplantation. Patients and Methods: Inclusion criteria: patients in first progression or relapse after at least one autologous transplantation, including those who had received bortezomib or thalidomide before transplant. Exclusion criteria: subjects with neuropathy above grade 1 or non secretory MM. Primary study end point was time to progression (TTP). Secondary end points included safety, response rate, progression-free survival (PFS) and overall survival (OS). Treatment was scheduled as follows: bortezomib 1.3 mg/m2 was given as an i.v bolus on Days 1, 4, 8 and 11 followed by a 10-Day rest period (days 12 to 21) for 8 cycles (6 months) and then on Days 1, 8, 15, 22 followed by a 20-Day rest period (days 23 to 42) for 4 cycles (6 months). In both arms, thalidomide was scheduled at 200 mg/Day orally for one year and dexamethasone 40 mg/Day orally four days every three weeks for one year. Patients reaching remission could proceed to a new stem cell harvest. However, transplantation, either autologous or allogeneic, could only be performed in patients who completed the planned one year treatment period. Response was assessed by EBMT criteria, with additional category of near complete remission (nCR). Adverse events were graded by the NCI-CTCAE, Version 3.0.The trial was based on a group sequential design, with 4 planned interim analyses and one final analysis that allowed stopping for efficacy as well as futility. The overall alpha and power were set equal to 0.025 and 0.90 respectively. The test for decision making was based on the comparison in terms of the ratio of the cause-specific hazards of relapse/progression, estimated in a Cox model stratified on the number of previous autologous transplantations. Relapse/progression cumulative incidence was estimated using the proper nonparametric estimator, the comparison was done by the Gray test. PFS and OS probabilities were estimated by the Kaplan-Meier curves, the comparison was performed by the Log-Rank test. An interim safety analysis was performed when the first hundred patients had been included. The safety committee recommended to continue the trial. Results: As of 1st July 2010, 269 patients had been enrolled in the study, 139 in France (IFM 2005-04 study), 21 in Italy, 38 in Germany, 19 in Switzerland (a SAKK study), 23 in Belgium, 8 in Austria, 8 in the Czech republic, 11 in Hungary, 1 in the UK and 1 in Israel. One hundred and sixty nine patients were males and 100 females; the median age was 61 yrs (range 29-76). One hundred and thirty six patients were randomized to receive VTD and 133 to receive TD. The current analysis is based on 246 patients (124 in arm A, 122 in arm B) included in the second interim analysis, carried out when 134 events were observed. Following this analysis, the trial was stopped because of significant superiority of VTD over TD. The remaining patients were too premature to contribute to the analysis. The number of previous autologous transplants was one in 63 vs 60 and two or more in 61 vs 62 patients in arm A vs B respectively. The median follow-up was 25 months. The median TTP was 20 months vs 15 months respectively in arm A and B, with cumulative incidence of relapse/progression at 2 years equal to 52% (95% CI: 42%-64%) vs 70% (95% CI: 61%-81%) (p=0.0004, Gray test). The same superiority of arm A was also observed when stratifying on the number of previous autologous transplantations. At 2 years, PFS was 39% (95% CI: 30%-51%) vs 23% (95% CI: 16%-34%) (A vs B, p=0.0006, Log-Rank test). OS in the first two years was comparable in the two groups. Conclusion: VTD resulted in significantly longer TTP and PFS in patients relapsing after ASCT. Analysis of response and safety data are on going and results will be presented at the meeting. Protocol EU-DRACT number: 2005-001628-35.
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We propose an algorithm that extracts image features that are consistent with the 3D structure of the scene. The features can be robustly tracked over multiple views and serve as vertices of planar patches that suitably represent scene surfaces, while reducing the redundancy in the description of 3D shapes. In other words, the extracted features will off er good tracking properties while providing the basis for 3D reconstruction with minimum model complexity