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  • Author or Editor: C. A. López-Sánchez x
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Bird migration constitutes a redistribution of bird diversity that radically changes the composition of the bird community worldwide. It comprises about 19% of the world’s bird species. Several studies have indicated that changes in avian community structure and differences in bird richness in different seasons are mainly driven by seasonality and by winter harshness, and that the associated costs increase with the distance involved. Western Mexico is an important wintering area for most passerines that breed in western North America, and that travel long on the long-distance Central and Pacific migration routes. In this study, we examined bird species richness and diversity during the breeding and wintering seasons in the Central Sierra Madre Occidental (SMO), North Durango (Mexico) in relation to i) tree species diversity, ii) tree dimension, iii) forest stand density and site quality, iv) density and dimension of snag trees, and v) various climate variables. The overall aim of the study was to determine how the observed associations between bird species diversity and variables i-v are affected by the season considered (breeding or wintering). The diversity of bird species in the breeding season was not affected by any of the climate and forest stand variables considered. In contrast, bird species diversity in the wintering season was significantly and weakly to moderately associated with climate variables, tree species diversity and stand density, although not with density or dimension of snag trees. Bird species diversity was higher at lower elevations and in drier and warmer locations of the SMO. The association detected is therefore mainly a local migratory phenomenon.

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Acta Physiologica Hungarica
Authors: Cristina Sánchez López, C. Barriga, A. Rodríguez, L. Franco, M. Rivero, and J. Cubero

We describe a chronobiological study of the effects of the oral administration of the essential amino acid L-methionine to common quail ( Coturnix coturnix ). This amino acid is a precursor of the neurotransmitter acetylcholine which is responsible for controlling and maintaining wakefulness through the ventrolateral pre-optic area of the hypothalamus and controlling the REM sleep in the nucleus reticularis pontinus oralis (NRPO). The quail model was chosen as these birds are monophasic and active by day, as are humans. The animals were kept under a constant 12h:12h light/dark cycle, fed ad libitum and housed in separate cages equipped for activity recording. Methionine was administered daily (1 h before lights off) for 1 week (chronic treatment), with the birds divided into 4 groups: a capsule with 15 mg of L-methionine (Met15 treatment group); a capsule with 30 mg of L-methionine (Met30 treatment group); a capsule with methylcellulose as excipient (control group); no capsule (basal group). In addition, we compared the first day of treatment (acute experiment) with the basal and control results. Actimetry (DAS24©) was used to quantify the activity data, and the sleep/wake rhythm was analyzed using the Ritme© software package. The statistical analysis of the activity data was descriptive (± SD) and inferential (Tukey test). The data showed increased (p<0.05) mean diurnal activity pulses in the Met30 group versus the other groups in both the acute and the chronic experiments. No changes were found in nocturnal activity. The chronobiological analysis showed a significant increase in the MESOR parameter of the Met30 group in both chronic and acute experiments versus the other groups. The acrophase showed no significant changes, in all groups being at around 13:45 h. In conclusion, the oral administration of L-methionine increased diurnal activity; probably due to the stimulating neuromodulatory action of acetylcholine.

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Acta Alimentaria
Authors: O.N. Campas-Baypoli, D.I. Sánchez-Machado, C. Bueno-Solano, A.A. Escárcega-Galaz, and J. López-Cervantes

Moringa oleifera tree has been recognized internationally for its nutritional, therapeutic and medicinal properties. Dry seeds are rich sources of oil with a high potential of commercial exploitation. The present study reports the physicochemical characterization, polyphenol content, DPPH radical scavenging capacity and fatty acid profile of moringa seed oil, and the chemical composition of the seed cultivated in Sonora, Mexico. Moisture, ash, protein and lipid contents in the seed were found to be 4.7, 5.8, 26 and 39%, respectively. The oil showed a refractive index of 1.4642. The saponification number was 183 mg KOH/g oil, iodine value: 75 g I/100 g of oil, acid value: 0.49 (% oleic acid). The polyphenol content was 0.137 mg of gallic acid equivalent/g and DPPH radical scavenging capacity was 87.39%. The moringa seed oil was rich (68%) in the major fatty acid, oleic acid (C18:1n9). Moringa oil extracted by sonication showed a fatty acid profile and physicochemical properties comparable to the oil from seeds grown in different regions of the world. The optimization of the oil extraction process on a large scale shows high potential, as the oil could be marketed as edible vegetable oil, for frying purposes, or as a functional ingredient.

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