139 research outputs found

    Estrutura Política como Determinante dos Gastos Federais

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    Este artigo analisa a distribuição dos gastos federais entre os estados brasileiros. A hipótese principal é a de que outras variáveis além das sociais e geográficas são as que explicam as decisões de gastos federais. A estrutura política do país também é importante na determinação destas escolhas. As teorias positivas da alocação orçamentária tais como a congressista, partidária e eleitoral, são utilizadas para avaliar o papel desempenhado pelos arranjos políticos na alocação do orçamento federal. Um conjunto de variáveis político-eleitorais foi usado para testar a importância destas teorias. O teste das hipóteses utilizou uma análise de painel de 27 estados brasileiros de 1999 a 2003 e as variáveis dependentes utilizadas foram: transferências federais voluntárias e investimentos federais nos estados. Os resultados confirmam a hipótese, indicando que o alinhamento dos representantes partidários e o comportamento do eleitor em eleições passadas influenciam a distribuição de gastos entre os estados.Investment Federalismo, Gasto Público, Determinantes Políticos

    3D tracking of laparoscopic instruments using statistical and geometric modeling

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    International audienceDuring a laparoscopic surgery, the endoscope can be manipulated by an assistant or a robot. Several teams have worked on the tracking of surgical instruments, based on methods ranging from the development of specific devices to image processing methods. We propose to exploit the instruments' insertion points, which are fixed on the patients abdominal cavity, as a geometric constraint for the localization of the instruments. A simple geometric model of a laparoscopic instrument is described, as well as a parametrization that exploits a spherical geometric grid, which offers attracting homogeneity and isotropy properties. The general architecture of our proposed approach is based on the probabilistic Condensation algorithm

    Adaptive niche-based sampling to improve ability to find rare and elusive species: Simulations and field tests

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    This is the peer reviewed version of the following article: Chiffard, Marciau, Yoccoz, Mouillot, Duchateau, Nadeau, Fontanilles, Besnard. Adaptive niche-based sampling to improve ability to find rare and elusive species: Simulations and field tests. Methods in Ecology and Evolution. 2020;11(8):899-909, which has been published in final form at https://doi.org/10.1111/2041-210X.13399. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. Sampling efficiency is crucial to overcome the data crisis in biodiversity and to understand what drives the distribution of rare species.</li Adaptive niche‐based sampling (ANBS) is an iterative sampling strategy that relies on the predictions of species distribution models (SDMs). By predicting highly suitable areas to guide prospection, ANBS could improve the efficiency of sampling effort in terms of finding new locations for rare species. Its iterative quality could potentially mitigate the effect of small and initially biased samples on SDMs. In this study, we compared ANBS with random sampling by assessing the gain in terms of new locations found per unit of effort. The comparison was based on both simulations and two field surveys of mountain birds. We found an increasing probability of contacting the species through iterations if the focal species showed specialization in the environmental gradients used for modelling. We also identified a gain when using pseudo‐absences during first iterations, and a general tendency of ANBS to increase the omission rate in the spatial prediction of the species' niche or habitat. Overall, ANBS is an effective and flexible strategy that can contribute to a better understanding of distribution drivers in rare species. </ol

    Identification of Genes Regulating Gene Targeting by a High-Throughput Screening Approach

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    Homologous gene targeting (HGT) is a precise but inefficient process for genome engineering. Several methods for increasing its efficiency have been developed, including the use of rare cutting endonucleases. However, there is still room for improvement, as even nuclease-induced HGT may vary in efficiency as a function of the nuclease, target site, and cell type considered. We have developed a high-throughput screening assay for the identification of factors stimulating meganuclease-induced HGT. We used this assay to explore a collection of siRNAs targeting 19,121 human genes. At the end of secondary screening, we had identified 64 genes for which knockdown affected nuclease-induced HGT. Two of the strongest candidates were characterized further. We showed that siRNAs directed against the ATF7IP gene, encoding a protein involved in chromatin remodeling, stimulated HGT by a factor of three to eight, at various loci and in different cell types. This method thus led to the identification of a number of genes, the manipulation of which might increase rates of targeted recombination

    Carbon dioxide gas hydrate crystallization in porous silica gel particles partially saturated with a surfactant solution

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    This paper reports on investigations into the way carbon dioxide (CO2) hydrate forms in porous silica gel partially saturated with pure water or with a surfactant solution. The experiments, conducted at two different temperatures (278.2 and 279.2 K) and under a loading pressure of 3.8 MPa, used silica particles of different nominal pore diameters (30 and 100 nm), saturated at 80% pore volume with pure water or with a 100 ppm solution of either sodium dodecyl sulfate (SDS) or polyoxyethylenesorbitan monoleate (Tween-80). They were run following the “hydrate precursor method” developed in previous works (Duchateau et al., 2009, 2010) to form bulk hydrate under controlled subcooling conditions, and adapted for studying hydrate formation behavior in porous media. The work demonstrated that the successive hydrate formation and decomposition cycles involved in this method do not alter the pore size distribution in the porous media. At the two temperatures investigated, silica gel particles with a nominal pore diameter of 100 nm proved better suited to comparing the CO2-hydrate formation behaviors: higher water-to-hydrate conversions (>90 mol%) were effectively obtained for all the conditions tested making comparison of the results much easier. Of the two surfactants used, only SDS was found to produce a positive effect on both the hydrate formation kinetics and the amount of hydrate formed. Our visual observations of quiescent bulk systems (without porous silica gel) suggest that when SDS is present, CO2 hydrate forms not only at the w/g interface (where it occurs without SDS too), but also in the bulk water phase. This may explain the beneficial effect observed on the porous medium

    Emergency department outcome of elderly patients assisted by professional home services, the EPIGER study.

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    BACKGROUND: For the elderly population living at home, the implementation of professional services tends to mitigate the effect of loss of autonomy and increases their quality of life. While helping in avoiding social isolation, home services could also be associated to different healthcare pathways. For elderly patients, Emergency Departments (EDs) are the main entrance to hospital where previous loss of autonomy is associated to worst hospital outcomes. Part of elderly patients visiting EDs are still admitted to hospital for having difficulties coping at home without presenting any acute medical issue. There is a lack of data concerning elderly patients visiting EDs assisted by home services. Our aim was to compare among elderly patients visiting ED those assisted by professional home services to those who do not in terms of emergency resources' use and patients' outcome. METHODS: A multicenter, prospective cohort study was performed in 124 French EDs during a 24-h period on March 2016.Consecutive patients living at home aged ≥80 years were included. The primary objective was to assess the risk of mortality for patients assisted by professional home services vs. those who were not. Secondary objectives included admission rate and specific admission rate for "having difficulties coping at home". The primary endpoint was in-hospital mortality. Cox proportional-hazards regression model was used to test the association between professional home services and the primary endpoint. Multi variables logistic regressions were performed to assess secondary endpoints. RESULTS: One thousand one hundred sixty-eight patients were included, median age 86(83-89) years old,32% were assisted by professional home services. The overall in-hospital mortality rate was 7%. Assisted patients had more investigations performed. Home services were not associated with increased in-hospital mortality (HR = 1.34;95%CI [0.68-2.67]), nor with the admission rate (OR = 0.92;95%CI [0.65-1.30]). Assisted patients had a lower risk of being admitted for "having difficulties coping at home" (OR = 0.59;95%CI [0.38-0.92]). CONCLUSION: Professional home services which assist one-third of elderly patients visiting EDs, were not associated to lower in-hospital mortality or to an increased admission rate. Assisted patients were associated to a lower risk of being admitted for «having difficulties coping at home».Professional home services could result in avoiding some admissions and their corollary complications. TRIAL REGISTRATION: Clinicaltrial.gov - NCT02900391 , 09/14/2016, retrospectively registered

    Generation of redesigned homing endonucleases comprising DNA-binding domains derived from two different scaffolds

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    Homing endonucleases have become valuable tools for genome engineering. Their sequence recognition repertoires can be expanded by modifying their specificities or by creating chimeric proteins through domain swapping between two subdomains of different homing endonucleases. Here, we show that these two approaches can be combined to create engineered meganucleases with new specificities. We demonstrate the modularity of the chimeric DmoCre meganuclease previously described, by successfully assembling mutants with locally altered specificities affecting both I-DmoI and I-CreI subdomains in order to create active meganucleases with altered specificities. Moreover these new engineered DmoCre variants appear highly specific and present a low toxicity level, similar to I-SceI, and can induce efficient homologous recombination events in mammalian cells. The DmoCre based meganucleases can therefore offer new possibilities for various genome engineering applications
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