105 research outputs found
Synthesis and functionalization of biocompatible Tb:CePO4 nanophosphors with spindle-like shape
Monoclinic Tb:CePO4 nanophosphors with a spindle-like morphology and tailored size (in the nanometer and micrometer range) have been prepared through a very simple procedure, which consists of aging, at low temperature (120 C), ethylene glycol solutions containing only cerium and terbium acetylacetonates and phosphoric acid, not requiring the addition of surfactants or capping agents. The influence of the heating mode (conventional convection oven or microwave oven) and the Tb doping level on the luminescent, structural and morphological features of the precipitated nanoparticles have also been analyzed. This study showed that microwave-assisted heating resulted in an important beneficial effect on the luminescent properties of these nanophosphors. Finally, a procedure for the functionalization of the Tb:CePO4 nanoparticles with asparticdextran is also reported. The functionalized nanospindles presented negligible toxicity for Verocells, which along with theirs excellent luminescent properties, make them suitable for biomedical applications.Junta de Andalucía FQM6090España CICYT MAT2011-2359
The role of life-history and ecology in the evolution of color patterns in Australian chrysomeline beetles
The variation in animal coloration patterns has evolved in response to different visual strategies for reducing the risk of predation. However, the perception of animal coloration by enemies is affected by a variety of factors, including morphology and habitat. We use the diversity of Australian chrysomeline leaf beetles to explore relationships of visual ecology to beetle morphology and color patterns. There is impressive color pattern variation within the Chrysomelinae, which is likely to reflect anti-predatory strategies. Our phylogenetic comparative analyses reveal strong selection for beetles to be less distinct from their host plants, suggesting that the beetle color patterns have a camouflage effect, rather than the widely assumed aposematic function. Beetles in dark habitats were significantly larger than beetles in bright habitats, potentially to avoid detection by predators because it is harder for large animals to be cryptic in bright habitats. Polyphagous species have greater brightness contrast against their host plants than monophagous species, highlighting the conflict between a generalist foraging strategy and the detection costs of potential predators. Host plant taxa-Eucalyptus and Acacia-interacted differently with beetle shape to predict blue pattern differences between beetle and host plant, possibly an outcome of different predator complexes on these host plants. The variety of anti-predator strategies in chrysomelines may explain their successful radiation into a variety of habitats and, ultimately, their speciation
Morbidity, outcomes and cost-benefit analysis of wildlife rehabilitation in Catalonia (Spain)
Background There are few studies of careful examination of wildlife casualties in Wildlife Rehabilitation Centers. These studies are essential for detecting menaces to wild species and providing objective criteria about cost-benefit of treatments in those centers. The release rate is considered the main outcome indicator, but other parameters such as length of stay at the center and a cost-benefit index expressed as number of released animals per euro and day, could be used as reliable estimators of the rehabilitation costs. Methodology A retrospective study based on 54772 admissions recorded from 1995-2013 in the database of the Wildlife Rehabilitation Center of Torreferrussa (Catalonia, NW Spain) assessed the morbidity, outcomes and cost-benefits of the rehabilitation practices. Results Three hundred and two species were included: 232 birds (n = 48633), 37 mammals (n = 3293), 20 reptiles (n = 2705) and 13 amphibians (n = 141). The most frequent causes of admission were: 39.8% confiscation of protected species (89.4% passerines), 31.8% orphaned young animals (35.3% swifts, 21.7% diurnal raptors and owls) and 17.4% trauma casualties (46.7% raptors and owls). The highest proportion of releases was found in the captivity confiscation category [87.4% passerines (median time of stay: 12 days)], followed by the orphaned category [78% owls (66 days), 76.5% diurnal birds of prey (43 days), 75.6% hedgehogs (49 days), 52.7% swifts (19 days) and 52% bats (55 days)]. For the trauma group, 46.8% of releases were hedgehogs (44 days) and 25.6% owls (103 days). As regards the cost-benefit index, the trauma casualties and infectious diseases had the worse values with 1.3 and 1.4 released animals/euro/day respectively, and were particularly low in raptors, waders, marine birds and chiroptera. On the contrary, captivity (4.6) and misplacement (4.1) had the best index, particulary in amphibian, reptiles and passerines. Conclusions/significance Cost-benefit studies including the release rate, the time of stay at the center and the costbenefit index should be implemented for improving management efficiency of the Wildlife Rehabilitation Centers
Primera aproximación al uso de la ocupación del tapir (Tapirella bairdii Gill, 1865) como indicador de la integridad ecológica en la Reserva de la Biosfera Maya, Guatemala
La Reserva de la Biosfera Maya (RBM) es un área protegida de relevancia nacional, regional y mundial por la diversidad biológica asociada y los beneficios que se obtienen de esta. En su plan maestro se plantea el conjunto de elementos de conservación a partir de los cuales se orientan estrategias y se evalúa la efectividad de manejo de dicha reserva, entre los cuales se incluye a Tapirella bairdii (tapir), por lo que es importante contar con un monitoreo de esta especie como una herramienta para la administración de esta reserva. En el 2015 se inició el desarrollo de un protocolo de monitoreo basado en la estimación de la probabilidad de ocupación y el presente estudio constituye la continuación de esta iniciativa a través de la implementación de las temporadas de muestreo en 2017 y 2018. Se registró la presencia del tapir en cinco zonas núcleo de la RBM empleando trampas cámara y se estimó la probabilidad de ocupación. Los valores estimados sugieren una relación de la ocupación con la integridad ecológica, en la cual hay una mayor ocupación en áreas con menor perturbación. Se generaron modelos con cinco covariables relacionadas con amenazas potenciales, sin embargo fue el modelo nulo el que se seleccionó de acuerdo al criterio definido. Los resultados sugieren que la integridad ecológica en las áreas de estudio está siendo afectada como consecuencia de las presiones antrópicas por lo que es necesario el fortalecimiento de aquellas con menores valores de ocupación.
Agrocombustibles: ¿Otro negocio es posible?
Hoy en día, los agrocombustibles (principalmente biodiesel y bioetanol) son objeto de políticas públicas e incentivos, y se ha acelerado su producción a gran escala, con la intención de reducir las emisiones de gases de efecto invernadero, y por tanto contribuir a la mitigación del cambio climático. Las y los autores de este libro integran el Grup de Bionegocis, un espacio multidisciplinario impulsado desde la Campaña “No te Comas el Mundo”, que investiga en Cataluña desde el año 2007 sobre la temática de los agrocombustibles. El principal objetivo de esta publicación se ubica en profundizar algunos aspectos con el objetivo de brindar herramientas de reflexión y de acción. Pretende responder a preguntas tales como: ¿Qué son los agrocombustibles? ¿Es positivo su rendimiento energético? ¿Cuál es la huella hídrica de estos carburantes? ¿Son realmente una respuesta ante el calentamiento global? ¿De dónde proviene la materia prima? ¿Mejoran las condiciones de vida en los países del Sur? ¿Cuáles son los intereses corporativos en este rubro? ¿Generarán los agrocombustibles una mayor Deuda ecológica? ¿Es la segunda generación una respuesta adecuada? ¿Qué perspectivas tenemos ante la Soberanía alimentaria y la Soberanía energética?Peer reviewe
Importancia del roedor Mus musculus en enfermedades infecciosas relevantes en salud pública
El Mus musculus, es una especie de roedor miomorfo de la familia Muridae, comúnmente utilizado en experimentos de laboratorio, subdividiéndose en 4 subespecies; Mus musculus domesticus, Mus musculus musculus, Mus musculus castaneus y Mus musculus bactrianus (1). Es un múrido de tamaño pequeño y aspecto grácil, su peso aproximado es de 12,5 a 29 gr, su cola está recubierta de escamas presentando escaso pelo fino, su hocico es ligeramente puntiagudo, sus ojos son normalmente negros y pequeños, orejas redondeadas, presenta un pelaje de color gris en su etapa de juventud y en etapa adulta su coloración puede variar de clara a oscura (2), posee un numero estándar de cromosomas de 40 n con 19 pares de cromosomas autosómicos
Childhood abuse increases the risk of depressive and anxiety symptoms and history of suicidal behavior in Mexican pregnant women
Rapid Plant Identification Using Species- and Group-Specific Primers Targeting Chloroplast DNA
Plant identification is challenging when no morphologically assignable parts are available. There is a lack of broadly applicable methods for identifying plants in this situation, for example when roots grow in mixture and for decayed or semi-digested plant material. These difficulties have also impeded the progress made in ecological disciplines such as soil- and trophic ecology. Here, a PCR-based approach is presented which allows identifying a variety of plant taxa commonly occurring in Central European agricultural land. Based on the trnT-F cpDNA region, PCR assays were developed to identify two plant families (Poaceae and Apiaceae), the genera Trifolium and Plantago, and nine plant species: Achillea millefolium, Fagopyrum esculentum, Lolium perenne, Lupinus angustifolius, Phaseolus coccineus, Sinapis alba, Taraxacum officinale, Triticum aestivum, and Zea mays. These assays allowed identification of plants based on size-specific amplicons ranging from 116 bp to 381 bp. Their specificity and sensitivity was consistently high, enabling the detection of small amounts of plant DNA, for example, in decaying plant material and in the intestine or faeces of herbivores. To increase the efficacy of identifying plant species from large number of samples, specific primers were combined in multiplex PCRs, allowing screening for multiple species within a single reaction. The molecular assays outlined here will be applicable manifold, such as for root- and leaf litter identification, botanical trace evidence, and the analysis of herbivory
Detection of Mitochondrial COII DNA Sequences in Ant Guts as a Method for Assessing Termite Predation by Ants
Termites and ants contribute more to animal biomass in tropical rain forests than any other single group and perform vital ecosystem functions. Although ants prey on termites, at the community level the linkage between these groups is poorly understood. Thus, assessing the distribution and specificity of ant termitophagy is of considerable interest.We describe an approach for quantifying ant-termite food webs by sequencing termite DNA (cytochrome c oxidase subunit II, COII) from ant guts and apply this to a soil-dwelling ant community from tropical rain forest in Gabon. We extracted DNA from 215 ants from 15 species. Of these, 17.2% of individuals had termite DNA in their guts, with BLAST analysis confirming the identity of 34.1% of these termites to family level or better. Although ant species varied in detection of termite DNA, ranging from 63% (5/7; Camponotus sp. 1) to 0% (0/7; Ponera sp. 1), there was no evidence (with small sample sizes) for heterogeneity in termite consumption across ant taxa, and no evidence for species-specific ant-termite predation. In all three ant species with identifiable termite DNA in multiple individuals, multiple termite species were represented. Furthermore, the two termite species that were detected on multiple occasions in ant guts were in both cases found in multiple ant species, suggesting that anttermite food webs are not strongly compartmentalised. However, two ant species were found to consume only Anoplotermes-group termites, indicating possible predatory specialisation at a higher taxonomic level. Using a laboratory feeding test, we were able to detect termite COII sequences in ant guts up to 2 h after feeding, indicating that our method only detects recent feeding events. Our data provide tentative support for the hypothesis that unspecialised termite predation by ants is widespread and highlight the use of molecular approaches for future studies of ant-termite food webs
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