Search results for " recombination"
showing 10 items of 86 documents
Is the Mean Blood Leukocyte Telomere Length a Predictor for Sporadic Thoracic Aortic Aneurysm? Data from a Preliminary Study
2012
Telomeres have been postulated as a universal clock that shortens in parallel with cellular aging. They are specialized DNA-protein structures at the ends of chromosome with remarkable functions--preventing their recognition as double-stranded DNA breaks, protecting their recombination and degradation, and avoiding a DNA damage cellular response. Telomere shortening is currently considered the best aging marker, but is also a predictor for age-related diseases, including cardiovascular diseases. Biological age clearly seems to be a better predictor of vascular risk rather than chronological age. This concept is supported by key assumptions that peripheral blood leukocyte telomere content ac…
The first case of myoclonic epilepsy in a child with a de novo 22q11.2 microduplication
2011
Chromosome 22, particularly the q11.2 sub-band, has long been recognized as responsible for multiple congenital anomaly disorders. In particular, its susceptibility to subtle microdeletions or, more rarely, microduplications has been attributed to the presence of several low-copy repeats spanning the region as mediators of nonallelic homologous recombination that result in 22q11.2 rearrangements. While recent data suggest that the frequency of 22q11.2 microduplications could be approximately half of all deletions, now only 50 unrelated cases have been reported thus far. However, it is reasonable to suppose that microduplications of 22q11.2 may be largely undetected as a result of a less-dis…
An ancestral recombination graph for diploid populations with skewed offspring distribution
2013
A large offspring number diploid biparental multilocus population model of Moran type is our object of study. At each timestep, a pair of diploid individuals drawn uniformly at random contribute offspring to the population. The number of offspring can be large relative to the total population size. Similar `heavily skewed' reproduction mechanisms have been considered by various authors recently. Each diploid parental individual contributes exactly one chromosome to each diploid offspring, and hence ancestral lineages can only coalesce when in distinct individuals. A separation of timescales phenomenon is thus observed. A result of M\"{o}hle (1998) is extended to obtain convergence of the an…
A binary genetic approach to characterize TRPM5 cells in mice
2015
International audience; Transient receptor potential channel subfamily M member 5 (TRPM5) is an important downstream signaling component in a subset of taste receptor cells making it a potential target for taste modulation. Interestingly, TRPM5 has been detected in extra-oral tissues; however, the function of extra-gustatory TRPM5-expressing cells is less well understood. To facilitate visualization and manipulation of TRPM5-expressing cells in mice, we generated a Cre knock-in TRPM5 allele by homologous recombination. We then used the novel TRPM5-IRES-Cre mouse strain to report TRPM5 expression by activating a tau GFP transgene. To confirm faithful coexpression of tau GFP and TRPM5 we gene…
CEP63 deficiency promotes p53-dependent microcephaly and reveals a role for the centrosome in meiotic recombination
2015
Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM
The time course of recombinant production in Streptomyces coelicolor.
1971
SUMMARYThe process leading to gene recombination can be interrupted in the filamentous bacteriaStreptomyces coelicolorby growing mixed cultures on cellophane disks lying on complete medium. The mycelium is harvested, broken, diluted and the broken hyphae plated at different time intervals. By this means some markers can be excluded from heteroclones or from recombinant progeny in early samples. The recombinant pattern clearly changes with time, with an increase of markers contributed to the recombinant progeny. In crosses between male (NF) and female (UF) strains, the maleness is the first donor trait to appear in the cells of the recipient parent. The fertility factor does not produce a tr…
Non-radiative recombination centres in catalyst-free ZnO nanorods grown by atmospheric-metal organic chemical vapour deposition
2013
We have investigated the cathodoluminescence (CL) emission and the Raman spectra along individual ZnO nanorods grown by a catalyst-free method. The spatial correlation between the CL emission and the defect related Raman modes permits establishing a correspondence between the non-radiative recombination centres (NRRCs) and the defects responsible for the 275 cm−1 Raman band. According to this relation, the NRRCs in these nanorods are tentatively associated with complexes of zinc interstitials.
Millisecond radiative recombination in poly(phenylene vinylene)-based light-emitting diodes from transient electroluminescence
2007
The current and electroluminescence transient responses of standard poly phenylene vinylene -based light-emitting devices have been investigated. The electroluminescence time response is longer milliseconds scale than the current switch-off time by more than one order of magnitude, in the case of small area devices 0.1 cm2 . For large area devices 6 cm2 the electroluminescence decay time decreases from 1.45 ms to 100 s with increasing bias voltage. The fast current decay limits the electroluminescence decay at higher voltages. Several approaches are discussed to interpret the observed slow decrease of electroluminescence after turning off the bias. One relies upon the Langevin-type bimolecu…
Non radiative recombination centers in ZnO nanorods
2013
ABSTRACTNowadays, the nature of the non radiative recombination centres in ZnO is a matter of controversy; they have been related to extended defects, zinc vacancy complexes, and surface defects, among other possible candidates. We present herein the optical characterization of catalyst free ZnO nanorods grown by atmospheric MOCVD by microRaman and cathodoluminescence spectroscopies. The correlation between the defect related Raman modes and the cathodoluminescence emission along the nanorods permits to establish a relation between the non radiative recombination centers and the defects responsible for the local Raman modes, which have been related to Zn interstitial complexes.
Temperature dependence of recombination radiation in semiconductor nanostructures with quantum dots containing impurity complexes
2021
Temperature dependence of the spectral intensity of recombination radiation in a quasi-zero-dimensional structure, containing impurity complexes “A++e” (a hole localized on a neutral acceptor, interacting with an electron localized in the ground state of a quantum dot), has been investigated in an external electric field in the presence of tunneling decay of a quasistationary A+-state. Probability of dissipative tunneling of a hole has been calculated in the one-instanton approximation, and the influence of tunneling decay and of an external electric field on the A+-state binding energy and on the spectra of recombination radiation, associated with the optical transition of an electron from…