24 research outputs found
La importancia de los ácidos grasos en la leche materna y en las fórmulas lácteas
The best choice for feeding the newborn child is breast milk, and when it is not possible to breastfeed a baby, the breast milk is replaced by lacteal formula, which is why numerous studies focus their attention on the analysis of the diverse components of baby formula as well as functions in the breastfed baby. Fatty acids are components of great nutritional importance in the fetus and in the newborn child. Nowadays it is estimated that the fetus, during the last trimester of the gestational period and the newborn child, during the first six months of life, need a great contribution of araquidonic and docosahexaenoic acids, due to the fact that the speed of transformation of the predecessors to the hepatic level are not sufficient to cover the metabolic requirements of these fatty acids and it is the mother who contributes them through placental transport during gestation and her milk during lactation. The Organization of Food and Agriculture (FAO), the World Health Organization (WHO), the European Society of Gastroenterology, Hepatology and Pediatric Nutrition (ESPGHAN) and the American Academy of Pediatrics recommend that lacteal formula imitate the composition of the breast milk, especially in the fatty polyunsaturated acids (PUFA).<br><br>El alimento natural por excelencia para el recién nacido es la leche materna, cuando no es posible darla se sustituye por fórmulas lácteas, por lo que numerosos estudios enfocan su interés en el análisis de los diversos componentes de éstas, y sus funciones en el lactante. Los ácidos grasos son componentes de gran importancia nutricional tanto en el feto como en el recién nacido. Actualmente se estima que el feto, durante el último tercio del periodo gestacional y el recién nacido, durante los primeros seis meses de vida, requieren un gran aporte de ácidos araquidónico y docosahexaenoico, debido a que la velocidad de transformación de los precursores a nivel hepático no son suficientes para cubrir los requerimientos metabólicos de éstos ácidos grasos y es la madre quien los aporta a través del transporte placentario durante la gestación y a través de la leche durante la lactancia. La Organización para Alimentación y Agricultura (FAO), la Organización Mundial de la Salud (OMS) y la Sociedad Europea de Gastroenterología, Hepatología y Nutrición Pediátrica (ESPGHAN), así como la Academia Americana de Pediatría recomiendan que las fórmulas lácteas deben ser inocuas y similares a la composición de la leche humana y muy especialmente en los ácidos grasos poliinsaturados (PUFA)
Árboles del Santuario Histórico de Machu Picchu: Monitoreo de diversidad y carbono a largo plazo
Understanding how the richness, diversity, and carbon monitoring vary and are distributed through altitudinal gradients in Andean montane forests is essential to understand how these forests are adapting to global warming effects. Botanical explorations and general collections were carried out within the limits of the Historic Sanctuary of Machu Picchu in an altitude gradient of 1600 to 4200 m.a.s.l. Two permanent plots of 1.0 ha were established in the sectors of Intipunku (SHM – 01) at an altitude of 2,653 m.a.s.l and Kantupata (SHM-02) at an altitude of 3,200 m.a.s.l., with the standardized methodology of RAINFOR in 2013 and remedied in 2016. We updated the number of tree species for the Historic Sanctuary of Machu Picchu, 364 species are reported so far, this catalog includes all wild and cultivated species but also tree ferns and palm trees. In recent years, four new tree species have been described whose TYPE collections come from SHM forests: Ocotea alveatavan der Werff, Ocotea mollivillosavan der Werff (Lauraceae), Bunchosia cuscanaW.R. Anderson (Malpighiaceae), Ficus machupicchuensisC.C. Berg (Moraceae). In the two permanent plots, a total of 69 species were recorded in 1286 individuals. Individually in the SHM – 01 plot, 26 families, 36 genera and 45 species were recorded in 682 individuals; and in the SHM – 02 plot: 22 families, 28 genera and 31 species in 604 individuals. Stored aerial biomass was higher in the Intipunku sector (146 Mg ha-1) compared to Kantupata sector (101 Mg ha-1). Our research shows that the Andean forests of Machu Picchu provide important ecosystem services, and there is still much to do in terms of scientic research. The continued discovery of new tree species in the locality demonstrates the need for conservation to protect forests that support some of the highest levels of endemism in the world
Biomimetic, Mild Chemical Synthesis of CdTe-GSH Quantum Dots with Improved Biocompatibility
Multiple applications of nanotechnology, especially those involving highly fluorescent nanoparticles (NPs) or quantum dots (QDs) have stimulated the research to develop simple, rapid and environmentally friendly protocols for synthesizing NPs exhibiting novel properties and increased biocompatibility
Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates
Unidad de excelencia María de Maeztu CEX2019-000940-MAim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types
Local hydrological conditions influence tree diversity and composition across the Amazon basin
Tree diversity and composition in Amazonia are known to be strongly determined by the water supplied by precipitation. Nevertheless, within the same climatic regime, water availability is modulated by local topography and soil characteristics (hereafter referred to as local hydrological conditions), varying from saturated and poorly drained to well-drained and potentially dry areas. While these conditions may be expected to influence species distribution, the impacts of local hydrological conditions on tree diversity and composition remain poorly understood at the whole Amazon basin scale. Using a dataset of 443 1-ha non-flooded forest plots distributed across the basin, we investigate how local hydrological conditions influence 1) tree alpha diversity, 2) the community-weighted wood density mean (CWM-wd) – a proxy for hydraulic resistance and 3) tree species composition. We find that the effect of local hydrological conditions on tree diversity depends on climate, being more evident in wetter forests, where diversity increases towards locations with well-drained soils. CWM-wd increased towards better drained soils in Southern and Western Amazonia. Tree species composition changed along local soil hydrological gradients in Central-Eastern, Western and Southern Amazonia, and those changes were correlated with changes in the mean wood density of plots. Our results suggest that local hydrological gradients filter species, influencing the diversity and composition of Amazonian forests. Overall, this study shows that the effect of local hydrological conditions is pervasive, extending over wide Amazonian regions, and reinforces the importance of accounting for local topography and hydrology to better understand the likely response and resilience of forests to increased frequency of extreme climate events and rising temperatures
LONG-TERM IMPACT OF MAIZE AGROECOLOGICAL MANAGEMENT ON BACTERIAL COMMUNITIES AND SOIL HEALTH IN THE ARID NORTH OF MEXICO
Background. Soil management practices modify the microbial communities and the carbon stocks (organic, inorganic, and total). The increase in microbiological communities’ diversity improves the production of plants; thus, it is essential to understand the predominant bacterial taxa in the soil. Objective. The objective of the present study was to establish the bacterial communities’ alteration by agroecological management in maize crops in arid northern Mexico. Methodology. Bacterial diversity and composition were determined in soils from Coahuila, Mexico, under three different scenarios: i) Agroecological management (AM), ii) Conventional management (CM), and iii) Control (T, with no vegetation). In addition, pH, electrical conductivity (EC), and soil organic matter (SOM) were analyzed using standard methods. Bacterial DNA was extracted from the soil, amplifying the V3-V4 region of the 16S rRNA gene and sequencing with Illumina. The gene sequences were analyzed in QIIME. Results. A total of 20 bacterial phyla and 631 genera were registered. For AM, CM, and T, respectively, the most abundant genera were Tepidisphaera (7.02, 9.29, and 9.93 %), Sphingomonas (6.55, 5.15, and 4.06 %), Microvirga (2.64, 2.39, and 3.63 %), and Blastococcus (2.91, 3.10, and 3.37 %). A significant difference was observed among groups (p = 0.004), where AM was different, which suggests that the type of substrate determines the diversity and abundance of the bacterial community. Significant differences were found for pH and EC, with higher pH in CM (7.87) and T (7.86) soils. The EC was higher in AM (446 μ Scm-1) and T (419 μ Scm-1). On the other hand, AM showed the best result in SOM content (21.80 ± 1.10 gC kg-1). Implication. Therefore, AM in maize crops has the potential to conserve or restore C stock in degraded arid lands, increasing bacterial diversity, favoring the health of the soil. Conclusion. Agroecological management of maize crops soils in arid North of Mexico promotes greater bacterial diversity, which will favor the availability of nutrients for the future development of healthy plants