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1.
Phys Rev Lett ; 120(22): 221301, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29906152

RESUMEN

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

2.
Sci Rep ; 6: 21367, 2016 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-26883288

RESUMEN

The present study aimed at the molecular characterization of pathogenic and non pathogenic F. oxysporum f. sp. lycopersici strains isolated from tomato. The causal agent isolated from symptomatic plants and soil samples was identified based on morphological and molecular analyses. Pathogenicity testing of 69 strains on five susceptible tomato varieties showed 45% of the strains were highly virulent and 30% were moderately virulent. Molecular analysis based on the fingerprints obtained through ISSR indicated the presence of wide genetic diversity among the strains. Phylogenetic analysis based on ITS sequences showed the presence of at least four evolutionary lineages of the pathogen. The clustering of F. oxysporum with non pathogenic isolates and with the members of other formae speciales indicated polyphyletic origin of F. oxysporum f. sp. lycopersici. Further analysis revealed intraspecies variability and nucleotide insertions or deletions in the ITS region among the strains in the study and the observed variations were found to be clade specific. The high genetic diversity in the pathogen population demands for development of effective resistance breeding programs in tomato. Among the pathogenic strains tested, toxigenic strains harbored the Fum1 gene clearly indicating that the strains infecting tomato crops have the potential to produce Fumonisin.


Asunto(s)
Fusarium/clasificación , Fusarium/fisiología , Filogenia , Enfermedades de las Plantas/microbiología , ADN Intergénico , Variación Genética , Genotipo , Solanum lycopersicum/microbiología , Repeticiones de Microsatélite , Tipificación Molecular , Virulencia
3.
Chin Med J (Engl) ; 109(8): 635-8, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9206067

RESUMEN

OBJECTIVE: To study the role of chromosomal aberration in the causation of recurrent spontaneous abortion (RSA) in Chinese population. METHODS: A total of 514 Chinese couples with 2 or more spontaneous abortions at less than 24 weeks of gestation were included. For each proband, a minimum of 13 metaphases were analyzed by G-banding. Additional cells (usually 50-100 cells) were screened when mosaicism was suspected. Chi 2 test was used to compare the number and frequency of couples with and without balanced translocation with respect to whether liveborn was present or absent. Chi 2 test for trend was used to show whether a correlation existed between the occurrence of balanced translocation and the number of spontaneous abortions at ascertainment. RESULTS: The overall incidence of chromosome anomaly was 51 out of 514 (9.92%). Chi 2 test for trend analysis showed that the chance of one member of a couple being a balanced carrier increased with the number of spontaneous abortions. The chance of finding translocation in couples with liveborn was higher than that in couples without liveborn, but the difference was not statistically significant. We also found that pericentric inversion 9 did not play an important role in the causation of recurrent abortion. CONCLUSIONS: Cytogenetic analysis is indicated in couples with 2 or more spontaneous abortions and the chance of finding chromosomal aberration increases with the number of abortions at the time of ascertainment.


Asunto(s)
Aborto Habitual/genética , Mosaicismo , Translocación Genética , Cromosomas Humanos Par 12 , Cromosomas Humanos Par 19 , Femenino , Humanos , Masculino , Embarazo
4.
Med Biol Eng Comput ; 46(8): 789-97, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18496723

RESUMEN

We present a novel parametric power spectral density (PSD) estimation algorithm for nonstationary signals based on a Kalman filter with variable number of measurements (KFVNM). The nonstationary signals under consideration are modeled as time-varying autoregressive (AR) processes. The proposed algorithm uses a block of measurements to estimate the time-varying AR coefficients and obtains high-resolution PSD estimates. The intersection of confidence intervals (ICI) rule is incorporated into the algorithm to generate a PSD with adaptive window size from a series of PSDs with different number of measurements. We report the results of a quantitative assessment study and show an illustrative example involving the application of the algorithm to intracranial pressure signals (ICP) from patients with traumatic brain injury (TBI).


Asunto(s)
Presión Sanguínea , Lesiones Encefálicas/fisiopatología , Presión Intracraneal , Procesamiento de Señales Asistido por Computador , Algoritmos , Diagnóstico por Computador/métodos , Humanos , Monitoreo Fisiológico/métodos
5.
Artículo en Inglés | MEDLINE | ID: mdl-9066191

RESUMEN

DiGeorge syndrome is a developmental field defect involving the third and fourth branchial arches and pouches. It is characterised by conotruncal heart defect, thymic hypoplasia/aplasia, hypocalcemia secondary to hypoparathyroidism and dysmorphic facies. Most of the cases are associated with interstitial deletion of chromosome 22 which can be detected by fluorescent in situ hybridisation study. The clinical presentation of DiGeorge syndrome is highly variable, in both interfamilial and intrafamilial situations. Apart from DiGeorge syndrome, velocardiofacial syndrome and other conditions are also associated with the same interstitial deletion. Here we reported a Chinese family with the same submicroscopic deletion of chromosome 22 as evident by fluorescent in situ hybridisation, but with different clinical presentation; the two brothers had DiGeorge syndrome and velocardiofacial syndrome respectively whereas the mother was asymptomatic.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 22 , Síndrome de DiGeorge/genética , Adulto , Preescolar , Femenino , Humanos , Hibridación Fluorescente in Situ , Recién Nacido , Masculino
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