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C R Moreno

Publications and source records attributed to C R Moreno.

8 recordsLinked to original sources
PubMed2006

No associations between PrP genotypes and reproduction traits in INRA 401 sheep.

In this study, the potential association of PrP genotypes with ewe reproductive traits and lamb growth traits was investigated. Data were included on ewes and lambs of the INRA 401 breed from the Bourges-La Sapinière INRA experimental farm. This breed was chosen because of good breeding (prolificacy and maternal abilities) and carcass qualities, and the large number of available animals with performance records and PrP genotypes. Ewes were categorized into 3 PrP genotype classes: ARR homozygous, ARR heterozygous, and animals without any ARR haplotype. Two analyses differing in the traits considered were carried out. Firstly, the potential association of the PrP genotype of ewes with their reproduction traits (fertility, litter size, and ovulation rate) was studied. The data included 801, 779, and 587 genotyped ewes for fertility, litter size, and ovulation rate, respectively. Secondly, the association of the PrP genotype of the ewes with growth traits of their lambs (birth weight, ADG between 10 and 30 d of age) was investigated. The data included 3,749 and 3,512 lambs for birth weight and ADG, respectively. The different traits were analyzed using an animal model, where the PrP genotype effect was included as a fixed effect. The reproductive traits were modeled under a probit or a threshold approach. The results of this study indicate no evidence of an association between PrP genotypes and reproductive and growth traits. It is unlikely that selection for scrapie resistance will have an effect on the reproductive or performance traits studied in the INRA 401 breed.

Animals↗
PubMed2005

Interval mapping methods for detecting QTL affecting survival and time-to-event phenotypes.

Quantitative trait loci (QTL) are usually searched for using classical interval mapping methods which assume that the trait of interest follows a normal distribution. However, these methods cannot take into account features of most survival data such as a non-normal distribution and the presence of censored data. We propose two new QTL detection approaches which allow the consideration of censored data. One interval mapping method uses a Weibull model (W), which is popular in parametrical modelling of survival traits, and the other uses a Cox model (C), which avoids making any assumption on the trait distribution. Data were simulated following the structure of a published experiment. Using simulated data, we compare W, C and a classical interval mapping method using a Gaussian model on uncensored data (G) or on all data (G'=censored data analysed as though records were uncensored). An adequate mathematical transformation was used for all parametric methods (G, G' and W). When data were not censored, the four methods gave similar results. However, when some data were censored, the power of QTL detection and accuracy of QTL location and of estimation of QTL effects for G decreased considerably with censoring, particularly when censoring was at a fixed date. This decrease with censoring was observed also with G', but it was less severe. Censoring had a negligible effect on results obtained with the W and C methods.

Animals↗
PubMed1997

Do weekly and fast-rotating shiftwork schedules differentially affect duration and quality of sleep?

Characteristics of shiftwork schedules can have distinct impacts on workers' sleep. This report presents comparisons of the effects of two different shiftwork schedules on duration and quality of the main sleep episodes in comparable worker populations at two different petrochemical plants. No significant differences were found for sleep duration in comparing the two plants. However, within each plant's shift cycles, morning and night shifts showed shorter sleep durations than all other workdays and days off. Quality of sleep was perceived as lowest for night shifts of both plant schedules, and of lesser quality for weekly than for fast-rotating shifts. These results support recommendations for reducing the number of consecutive nights of shiftwork. However, before recommending any optimal shift schedule, interactions of sleep duration and quality with shift schedules need much further evaluation.

Adolescent↗
PubMed1990

Lateralization for the expression and perception of facial emotion as a function of age.

In order to test the hypothesis of right hemisphere changes with age, this study examined lateralization for facial emotion in young, middle-aged, and older women (N = 90). For expression, subjects were photographed while posing positive and negative emotions. Composite photographs were created and rated for intensity. For perception, subjects were required to make intensity judgements about emotional chimeric faces. Overall, subjects demonstrated significant left-sided facial asymmetry for expression and significant left hemispace biases for perception. The findings for facial expression were not influenced by emotional valence or resting face asymmetries. There were no changes in lateralization as a function of age for either expression or perception. Taken together, these findings lend support to the notion that the right hemisphere mediates emotional processing across the adult life span.

Adult↗
PubMed1989

Biological aspects and self-evaluation of shiftwork adaptation.

Two male truck drivers working in a Brazilian cellulose plant and classifying themselves as "well-" and "ill-adapted" to a shiftwork schedule of 4 days-on and 1 day-off, participated in an autorhythmometric study. Psychophysiological self-ratings (calmness, stress and alertness), oral temperature measurements and urine collections (detection of K+,Na+ and 17-OH concentrations) were performed regularly during the waking period for 15 consecutive days during the shift schedule--the midday shift (11:00 to 19:00 h), early-morning shift (03:00 to 11:00 h) and evening shift (18:00 to 02:00 h), including days-off. Cosine fitting of the data to a successive running one-day window revealed different individual temporal patterns, with the "well-adapted" subject showing a relatively stable phase relationship of the variables under study and the "ill-adapted" subject showing a less stable relationship. The different patterns could explain, at least partially, the fact that one subject feels "adapted" to shiftwork and the other not.

Adaptation, Physiological↗
PubMedDate not supplied

Individual differences in night and continuously-rotating shiftwork: seeking anticipatory rather than compensatory strategy.

Individual differences in adaptation to night or continuously-rotating shiftwork may reflect distinct strategies of coping with temporal challenges of the environment. Rather than studying compensatory mechanisms, we have chosen the anticipatory response of the sleep onset time preceding work in order to reveal the strategy used by workers submitted to those shift systems including night work. Comprehensive interviews, taking into account several aspects of the workers' lives, allowed for a classification of the subjects in terms of adaptation to their working schedules. Night workers go to bed once a day, whereas shiftworkers prefer to allocate their sleep onsets to two different periods of the day. For both cases, the more well-adapted an individual is, according to the classification obtained by the interviews, the more regular will be the choice of sleep onset times.

Adaptation, Physiological↗