52 research outputs found
Etiologie particuliere de l’encephalite limbique : la neurosyphilis (a propos de deux cas)
L’encéphalite limbique syphilitique est une affection rare et son incidence est inconnue nous rapportons l’observation deux patients hospitalisés pour troubles du comportement, troubles de mémoire et crises épileptiques, l’IRM cérébrale montrait un hypersignal sur les séquences pondérées en T2 et FLAIR des régions temporo-limbiques, la sérologie de la syphilis fut positive dans le sang et le LCR. Le diagnostic d’encéphalite limbique syphilitique fut retenu sur un ensemble d’arguments clinique, biologique etradiologique. Le traitement spécifique de la neurosyphilis a permis une amélioration de l’état neurologique des deux patients
The Terminating-Knockoff Filter: Fast High-Dimensional Variable Selection with False Discovery Rate Control
We propose the Terminating-Knockoff (T-Knock) filter, a fast variable
selection method for high-dimensional data. The T-Knock filter controls a
user-defined target false discovery rate (FDR) while maximizing the number of
selected variables. This is achieved by fusing the solutions of multiple early
terminated random experiments. The experiments are conducted on a combination
of the original predictors and multiple sets of randomly generated knockoff
predictors. A finite sample proof based on martingale theory for the FDR
control property is provided. Numerical simulations show that the FDR is
controlled at the target level while allowing for a high power. We prove under
mild conditions that the knockoffs can be sampled from any univariate
probability distribution with existing finite expectation and variance. The
computational complexity of the proposed method is derived and it is
demonstrated via numerical simulations that the sequential computation time is
multiple orders of magnitude lower than that of the strongest benchmark methods
in sparse high-dimensional settings. The T-Knock filter outperforms
state-of-the-art methods for FDR control on a simulated genome-wide association
study (GWAS), while its computation time is more than two orders of magnitude
lower than that of the strongest benchmark methods. An open source R package
containing the implementation of the T-Knock filter is available at
https://github.com/jasinmachkour/tknock.Comment: 26 pages, 13 figures, 2 table
Megaselia scalaris (Diptera: Phoridae): an opportunistic endoparasitoid of the endangered Mexican redrump tarantula, Brachypelma vagans (Araneae: Theraphosidae)
Volume: 43Start Page: 115End Page: 11
Dimorphism and population size of the Mexican redrump tarantula, Brachypelma vagans (Araneae: Theraphosidae), in Southeast Mexico
AbstractAs a general rule, spiders exhibit sexual dimorphism and their populations may differ in size according to season duration and resource availability. However, few studies have focused on dimorphism in tarantulas. Mexican redrump tarantulas, Brachypelma vagans, listed in CITES, have an exceptionally wide distribution. Surprisingly, there are no studies on the possible relationship between the abundance of tarantulas per population and the geographical areas where they are present, or on how the distribution pattern of this spider may affect individual morphological characteristics. Furthermore, there are no studies on sexual dimorphism within the genus Brachypelma. The aim of the study is to determine the existence of sexual and geographical dimorphism in populations of B. vagans. It was observed that the abundance of spiders per population may vary according to the geographical areas where they were recorded. In six localities in southern Mexico, we recorded morphological data on adult tarantulas. Sexual dimorphism was clearly observed at the site that presented numerous spiders characterized by much smaller females. Since the results of this study demonstrate differences in tarantula number of individuals per locality in southern Mexico, they make an important contribution to the conservation of this species
Insect attraction by webs of Nephila clavipes (Araneae: Nephilidae)
Volume: 38Start Page: 135End Page: 13
The phylogeographic history of Megistostegium (Malvaceae) in the dry, spiny thickets of southwestern Madagascar using RAD-seq data and ecological niche modeling
The spiny thicket of southwestern Madagascar represents an extreme and ancient landscape with extraordinary levels of biodiversity and endemism. Few hypotheses exist for explaining speciation in the region and few plant studies have explored hypotheses for species diversification. Here, we investigate three species in the endemic genus Megistostegium (Malvaceae) to evaluate phylogeographic structure and explore the roles of climate, soil, and paleoclimate oscillations on population divergence and speciation throughout the region. We combine phylogenetic and phylogeographic inference of RADseq data with ecological niche modeling across space and time. Population structure is concurrent with major rivers in the region and we identify a new, potentially important biogeographic break coincident with several landscape features. Our data further suggests that niches occupied by species and populations differ substantially across their distribution. Paleodistribution modeling provide evidence that past climatic change could be responsible for the current distribution, population structure, and maintenance of species in Megistostegium
- …