102 research outputs found
Prótesis 3D para corregir eje corporal y equilibro en lechuza de campanario y cernícalo americano
The amputation of a pelvic limb in raptor, must be carefully evaluated and taken as the last possibility to save the life of the bird, because after the amputation, several degenerative factors can occur, such as alteration of the body axis, an incorrect distribution of weight and bumblefoot. A good alternative to counteract these problems is the use of prostheses that seek to help recover the body axis and maintain good posture. The use of 3D printers for this type of project offers a more accessible and easier to work alternative due to its versatility in both design and materials. The present project tests the design of a 3D prosthesis and documents the correction of the body axis and the modification of its use in the daily activities of an american kestrel and a barn owl with a tibiotarsal amputation in its distal third. Although the use of prostheses does not allow the reintroduction of the birds, it gives the opportunity to integrate them into conservation programs such as captivity reproduction or environmental education.La amputación de miembros pélvicos en aves rapaces, debe ser evaluada con detenimiento y considerada como el último recurso para salvar la vida del ave, debido a que posterior a la amputación, pueden derivarse una serie de factores degenerativos, como la alteración de eje corporal, distribución inadecuada del peso corporal y pododermatitis. Una buena alternativa para contrarrestar estos problemas, es el uso de prótesis, que busquen recuperar el eje corporal y mantener una buena postura en el ave. El uso de impresoras 3D para este tipo de proyectos, ofrece una alternativa más accesible y sencilla debido a su versatilidad tanto en diseño como en materiales. El presente proyecto pone a prueba el diseño de una prótesis 3D y documenta la corrección de eje corporal e incorporación de la prótesis en las actividades diarias de un cernícalo americano (Falco sparverius) y una lechuza de campanario (Tyto alba), ambas con una amputación tibiotarsal en su tercio distal. A pesar de que la utilización de prótesis no permite la reintroducción de las aves al medio ambiente, ofrece una oportunidad para integrar dichas aves en programas de conservación, tales como reproducción en cautiverio o educación ambiental
Emerging energy sources' social acceptability: Evidence from marine-based energy projects
Any decrease in global warming and its effects can only occur with a substantial reduction in anthropogenic CO2 emissions. In this context, renewable energy sources, particularly emerging sources, may play a central role in accelerating the transition from fossil fuels to cleaner energy sources. Emerging energy sources are renewable and have the potential to reduce global warming emissions; however, they are in the early development stages. These technologies include enhanced geothermal processes, artificial photosynthesis, and marine energy. In this study, we assess the main attributes that determine the social acceptance of renewable marine energy projects, highlighting individual preferences and heterogeneity for these projects. The results show that energy generation, ecological impact, job creation, co-ownership, and distributional justice are statistically significant attributes that support projects. However, individual preferences are highly heterogeneous. The existence of distinct classes (two in this case) with different preferences for marine energy attributes indicates that the one-size-fits-all approach may be inappropriate. Instead, policymakers and energy producers should tailor their proposals to meet the needs of both groups, considering their preferences and concerns
A Simultaneous Test of Synchrony Causal Factors in Muskrat and Mink Fur Returns at Different Scales across Canada
Synchrony among populations has been attributed to three major hypotheses: dispersal, the Moran effect, and trophic-level interactions. Unfortunately, simultaneous testing of these hypotheses demands complete and detailed data, which are scarce for ecological systems.Hudson's Bay Company data on mink and muskrat fur returns in Canada represent an excellent opportunity to test these hypotheses because of the detailed spatial and temporal data from this predator-prey system. Using structural equation modelling, support for each hypothesis was evaluated at two spatial scales: across Canada and dividing the country into three regions longitudinally. Our results showed that at both scales mink synchrony is a major factor determining muskrat synchrony, supporting the hypothesis of trophic-level interactions, but the influence of winter precipitation synchrony is also important in eastern Canada. Moreover, mink synchrony is influenced principally by winter precipitation synchrony at the level of all Canada (Moran effect), but by distance at regional level, which might suggest some influence of dispersal at this level.Our result is one of the few reports of synchrony mediated by trophic-level interactions, highlighting the importance of evaluation of scale effects in population synchrony studies
Oligophrenin-1: the link between calcium-regulated exocytosis and compensatory endocytosis in neuroendocrine cells
In neuroendocrine cells, hormones and neuropeptides are released from large-dense core vesicles (secretory granules) by calcium-regulated exocytosis. Following exocytosis, compensatory uptake of membrane is required to maintain membrane homeostasis and allow recycling of secretory vesicle membranes. How these cells initiate and regulate this compensatory endocytosis remains poorly understood. Our recent data suggests that oligophrenin-1 (OPHN1) is a link coupling calcium-regulated exocytosis to compensatory endocytosis of secretory granules in the adrenal chromaffin cells (Houy et al., 2015, J Neurosci. 2015, 35:11045-55). Here, we highlight the major evidence and discuss how OPHN1 could couple these two processes
Ecology of the collapse of Rapa Nui society
Collapses of food producer societies are recurrent events in prehistory and have triggered a growing concern for identifying the underlying causes of convergences/divergences across cultures around the world. One of the most studied and used as a paradigmatic case is the population collapse of the Rapa Nui society. Here, we test different hypotheses about it by developing explicit population dynamic models that integrate feedbacks between climatic, demographic and ecological factors that underpinned the sociocultural trajectory of these people. We evaluate our model outputs against a reconstruction of past population size based on archaeological radiocarbon dates from the island. The resulting estimated demographic declines of the Rapa Nui people are linked to the long-term effects of climate change on the island's carrying capacity and, in turn, on the 'per-capita food supply'
¿Las lechuzas de campanario (Tyto alba) son estrictamente nocturnas? Cuidado parental de una hembra en cautiverio.
Se describen las actividades diurnas y nocturnas de una hembra de lechuza de campanario en cautiverio, con énfasis en la asignación de tiempo a sus actividades diurnas y nocturnas. Las observaciones se realizaron mediante la vídeo-grabación y posterior revisión de sus actividades al interior de una caja nido. La hembra presentó un patrón de actividades diurnas. Se discute el papel de disponibilidad de alimento y el número de polluelos producidos en este patrón
Analysis of the association between spawning time QTL markers and the biannual spawning behavior in rainbow trout (Oncorhynchus mykiss)
The rainbow trout is a salmonid fish that occasionally exhibits broodstocks with biannual spawning behavior, a phenomenon known as a double annual reproductive cycle (DARC). Spawning time quantitative trait loci (SPT-QTLs) affect the time of the year that female rainbow trout spawn and may influence expression of the DARC trait. In this study, microsatellite markers linked and unlinked to SPT-QTLs were genotyped to investigate the underlying genetics of this trait. SPT-QTLs influenced the DARC trait since in two case-control comparisons three linked markers (OmyFGT12TUF, One3ASC and One19ASC) had significant levels of allelic frequency differentiation and marker-character association. Furthermore, alleles of One3ASC and One19ASC had significantly higher frequencies in populations that carried the DARC trait
Consensus guidelines for the use and interpretation of angiogenesis assays
The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference
Influence of androgen receptor in vascular cells on reperfusion following hindlimb ischaemia
AIMS:Studies in global androgen receptor knockout (G-ARKO) and orchidectomised mice suggest that androgen accelerates reperfusion of the ischaemic hindlimb by stimulating angiogenesis. This investigation used novel, vascular cell-specific ARKO mice to address the hypothesis that the impaired hindlimb reperfusion in G-ARKO mice was due to loss of AR from cells in the vascular wall. METHODS AND RESULTS:Mice with selective deletion of AR (ARKO) from vascular smooth muscle cells (SM-ARKO), endothelial cells (VE-ARKO), or both (SM/VE-ARKO) were compared with wild type (WT) controls. Hindlimb ischaemia was induced in these mice by ligation and removal of the femoral artery. Post-operative reperfusion was reduced in SM-ARKO and SM/VE-ARKO mice. Immunohistochemistry indicated that this was accompanied by a reduced density of smooth muscle actin-positive vessels but no change in the density of isolectin B4-positive vessels in the gastrocnemius muscle. Deletion of AR from the endothelium (VE-ARKO) did not alter post-operative reperfusion or vessel density. In an ex vivo (aortic ring culture) model of angiogenesis, AR was not detected in vascular outgrowths and angiogenesis was not altered by vascular ARKO or by exposure to dihydrotestosterone (DHT 10(-10)-10(-7)M; 6 days). CONCLUSION:These results suggest that loss of AR from vascular smooth muscle, but not from the endothelium, contributes to impaired reperfusion in the ischaemic hindlimb of G-ARKO. Impaired reperfusion was associated with reduced collateral formation rather than reduced angiogenesis
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