962 resultados para Stars: distances
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Ms1/STARS is a novel muscle-specific actin-binding protein that specifically modulates the myocardin-related transcription factor (MRTF)-serum response factor (SRF) regulatory axis within striated muscle. This ms1/STARS-dependent regulatory axis is of central importance within the cardiac gene regulatory network and has been implicated in cardiac development and postnatal cardiac function/homeostasis. The dysregulation of ms1/STARS is associated with and causative of pathological cardiac phenotypes, including cardiac hypertrophy and cardiomyopathy. In order to gain an understanding of the mechanisms governing ms1/STARS expression in the heart, we have coupled a comparative genomic in silico analysis with reporter, gain-of-function, and loss-of-function approaches. Through this integrated analysis, we have identified three evolutionarily conserved regions (ECRs), α, SINA, and DINA, that act as cis-regulatory modules and confer differential cardiac cell-specific activity. Two of these ECRs, α and DINA, displayed distinct regulatory sensitivity to the core cardiac transcription factor GATA4. Overall, our results demonstrate that within embryonic, neonatal, and adult hearts, GATA4 represses ms1/STARS expression with the pathologically associated depletion of GATA4 (type 1/type 2 diabetic models), resulting in ms1/STARS upregulation. This GATA4-dependent repression of ms1/STARS expression has major implications for MRTF-SRF signaling in the context of cardiac development and disease.
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"Vegeu el resum a l'inici del document del fitxer adjunt."
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We propose to analyze shapes as “compositions” of distances in Aitchison geometry asan alternate and complementary tool to classical shape analysis, especially when sizeis non-informative.Shapes are typically described by the location of user-chosen landmarks. Howeverthe shape – considered as invariant under scaling, translation, mirroring and rotation– does not uniquely define the location of landmarks. A simple approach is to usedistances of landmarks instead of the locations of landmarks them self. Distances arepositive numbers defined up to joint scaling, a mathematical structure quite similar tocompositions. The shape fixes only ratios of distances. Perturbations correspond torelative changes of the size of subshapes and of aspect ratios. The power transformincreases the expression of the shape by increasing distance ratios. In analogy to thesubcompositional consistency, results should not depend too much on the choice ofdistances, because different subsets of the pairwise distances of landmarks uniquelydefine the shape.Various compositional analysis tools can be applied to sets of distances directly or afterminor modifications concerning the singularity of the covariance matrix and yield resultswith direct interpretations in terms of shape changes. The remaining problem isthat not all sets of distances correspond to a valid shape. Nevertheless interpolated orpredicted shapes can be backtransformated by multidimensional scaling (when all pairwisedistances are used) or free geodetic adjustment (when sufficiently many distancesare used)
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Time scale parametric spike train distances like the Victor and the van Rossum distancesare often applied to study the neural code based on neural stimuli discrimination.Different neural coding hypotheses, such as rate or coincidence coding,can be assessed by combining a time scale parametric spike train distance with aclassifier in order to obtain the optimal discrimination performance. The time scalefor which the responses to different stimuli are distinguished best is assumed to bethe discriminative precision of the neural code. The relevance of temporal codingis evaluated by comparing the optimal discrimination performance with the oneachieved when assuming a rate code.We here characterize the measures quantifying the discrimination performance,the discriminative precision, and the relevance of temporal coding. Furthermore,we evaluate the information these quantities provide about the neural code. Weshow that the discriminative precision is too unspecific to be interpreted in termsof the time scales relevant for encoding. Accordingly, the time scale parametricnature of the distances is mainly an advantage because it allows maximizing thediscrimination performance across a whole set of measures with different sensitivitiesdetermined by the time scale parameter, but not due to the possibility toexamine the temporal properties of the neural code.
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Variation in melanin coloration is widespread and often associated with other phenotypic traits. A recent study showed that darker-reddish pheomelanic Barn Owls (Tyto alba) move longer distances between birth and breeding sites. Because this study considered only individuals recovered within a limited study area, it remains unclear whether the association between melanism and dispersal applies to a larger geographic scale. I analysed an independent dataset of birds ringed in the same study area but recovered dead along roads within and outside this area. As expected, dark pheomelanic owls dispersed further than lighter reddish conspecifics at a larger spatial scale.
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Échelle(s) : [ca 1:1 600 000]
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Échelle(s) : [ca 1:2 440 000], échelle 100 kilomètres [= 4,1 cm]
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Échelle(s) : [ca 1:1 600 000]
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Échelle(s) : [ca 1:710 000], échelle de 10 myriamètres [= 14,1 cm]
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Échelle(s) : [ca 1:2 440 000], échelle 100 kilomètres [= 4,1 cm]
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The objective of this study was the identification of the attributes and dimensions of service quality affecting the service performance of the five stars resort hotels located in the Cape Verde Islands. The reason boosting the initiative to do this research was the paramount role of the resort hotels in the development of the travel and tourism sector in Cape Verde, and the impact that today this sector has had in the economy of that country. The research opens with a literature review on the service quality theory in the hotel industry, starting from the middle of the 1980s with the classic model of service quality and SERVQUAL instrument to the analysis of recent models of service quality measurement in the hotel industry, as it is an example the scale of items developed in 2003 in the Lodging Quality Index (LQI). Furthermore, the study elaborates an analysis on the importance of the travel and tourism activities in the Cape Verde Islands, and it evidences the enormous importance of those activities in the performance of the Cape Verdean hotel industry. In sequence the study analyzes in details the hotel industry of Cape Verde and it identifies the market size of the five stars resort hotels and their current operators in that market. Moreover, the research develops with an online questionnaire elaborated and sent through the platforms of travel websites and communities to the guests whom have experienced the service of the five stars resort hotels located in the Cape Verde Islands. The scope of the questionnaire was to assess the attributes and dimensions of service quality in the five stars resort hotels of Cape Verde. The results of the questionnaire were in sequence analyzed through descriptive and applied statistics, using Microsoft Excel and the Statistical Package for Social Science (SPSS). Content validity analysis, factor analysis, and reliability analysis of the factors were made to purify an initial scale of 47 items of service quality. An instrument with three dimensions covering twenty four attributes of service quality assessment in the five stars resort hotels of Cape Verde was finally created. The three dimensions found were: staff competence; food and entertainment; and physical facilities. This study on the service in the five stars resort hotels of Cape Verde ends with brief comments on the status of service quality according to the identified dimensions and their attributes. In the conclusion, the study summarizes the whole work and gives some directions for future research.
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Ancien possesseur : Argenson, Antoine-René de Voyer (1722-1787 ; marquis de Paulmy d')
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A second set of UBVRI photometry results for nearby stars of Gliese's (1969) catalog and its supplements, including in this case some multiple systems, are presented. Most of the observations were carried out between July 1984 and December 1985 at Calar Alto with the 1.23-m Centro Astronomico Hispano-Aleman telescope and the 1.52-m Observatorio Astronomico Nacional telescope. The number of observations of program and standard stars for the six runs and the final results for 60 stars are presented.
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A new statistical parallax method using the Maximum Likelihood principle is presented, allowing the simultaneous determination of a luminosity calibration, kinematic characteristics and spatial distribution of a given sample. This method has been developed for the exploitation of the Hipparcos data and presents several improvements with respect to the previous ones: the effects of the selection of the sample, the observational errors, the galactic rotation and the interstellar absorption are taken into account as an intrinsic part of the formulation (as opposed to external corrections). Furthermore, the method is able to identify and characterize physically distinct groups in inhomogeneous samples, thus avoiding biases due to unidentified components. Moreover, the implementation used by the authors is based on the extensive use of numerical methods, so avoiding the need for simplification of the equations and thus the bias they could introduce. Several examples of application using simulated samples are presented, to be followed by applications to real samples in forthcoming articles.