3,263 research outputs found

    Development, Test and Validation of a Mechatronic Device for Spasticity Quantification

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    Abstract Spasticity is a common pathological phenomenon in clinical practices, frequently expressed as a stroke, multiple sclerosis or cerebral palsy. The accurate quantification of spasticity allows early action to prevent the potentially irreversible consequences. The aim of this work is to develop and implement a mechatronic device for the accurate quantification of spasticity, which is able to differentiate spasticity from other motor disorders. The proposed method is based on the quantification of the tonic stretch reflex threshold (TSRT) for the assessment of the range of motion of the limb affected by spasticity. In order to validate the developed device, experimental trials have been conducted, considering the flexor muscle of the elbow joint. The developed device was tested, first in a laboratory environment with healthy subjects and secondly, in a clinical environment with the collaboration of patients with spasticity. The evaluations in th clinical environment were performed on three different days in order to evaluate the reproducibility of the obtained results. The experimental trials confirm the sensibility, reproducibility and reliability of spasticity quantification based on the TSRT method. This project has been developed in cooperation with the Hospital of Braga and Fisimaia rehabilitation clinic, both in Portugal

    Variables impacting poultry meat quality from production to pre-slaughter: a review

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    Poultry meat quality has been widely studied, and has become a growing demand of the international market. Parameters that affect meat quality are complex, and occur throughout the production chain. The constant concern with meat quality by the exporting sectors is a response to consumers' demands, and is achieved by increasing efficiency, and investments in personnel training on quality. Understanding where critical points are in the poultry meat production chain, and investing in solving critical problems may lead to better control and management, and consequent reduction of losses. Production and management practices, from farm to processing plant, play an important role in meat quality, and the use of technologies to reduce risk factors throughout the production chain will allow the production of better quality poultry meat not only for exports, but also for the domestic market. This review describes the main factors that influence poultry meat quality in the production chain.20121

    Stellar Coronal and Wind Models: Impact on Exoplanets

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    Surface magnetism is believed to be the main driver of coronal heating and stellar wind acceleration. Coronae are believed to be formed by plasma confined in closed magnetic coronal loops of the stars, with winds mainly originating in open magnetic field line regions. In this Chapter, we review some basic properties of stellar coronae and winds and present some existing models. In the last part of this Chapter, we discuss the effects of coronal winds on exoplanets.Comment: Chapter published in the "Handbook of Exoplanets", Editors in Chief: Juan Antonio Belmonte and Hans Deeg, Section Editor: Nuccio Lanza. Springer Reference Work

    Widespread forest vertebrate extinctions induced by a mega hydroelectric dam in lowland Amazonia

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    Mega hydropower projects in tropical forests pose a major emergent threat to terrestrial and freshwater biodiversity worldwide. Despite the unprecedented number of existing, underconstruction and planned hydroelectric dams in lowland tropical forests, long-term effects on biodiversity have yet to be evaluated. We examine how medium and large-bodied assemblages of terrestrial and arboreal vertebrates (including 35 mammal, bird and tortoise species) responded to the drastic 26-year post-isolation history of archipelagic alteration in landscape structure and habitat quality in a major hydroelectric reservoir of Central Amazonia. The Balbina Hydroelectric Dam inundated 3,129 km2 of primary forests, simultaneously isolating 3,546 land-bridge islands. We conducted intensive biodiversity surveys at 37 of those islands and three adjacent continuous forests using a combination of four survey techniques, and detected strong forest habitat area effects in explaining patterns of vertebrate extinction. Beyond clear area effects, edge-mediated surface fire disturbance was the most important additional driver of species loss, particularly in islands smaller than 10 ha. Based on species-area models, we predict that only 0.7% of all islands now harbor a species-rich vertebrate assemblage consisting of ≥80% of all species. We highlight the colossal erosion in vertebrate diversity driven by a man-made dam and show that the biodiversity impacts of mega dams in lowland tropical forest regions have been severely overlooked. The geopolitical strategy to deploy many more large hydropower infrastructure projects in regions like lowland Amazonia should be urgently reassessed, and we strongly advise that long-term biodiversity impacts should be explicitly included in pre-approval environmental impact assessments

    Tearing Out the Income Tax by the (Grass)Roots

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    Landscapes are increasingly fragmented, and conservation programs have started to look at network approaches for maintaining populations at a larger scale. We present an agent-based model of predator–prey dynamics where the agents (i.e. the individuals of either the predator or prey population) are able to move between different patches in a landscaped network. We then analyze population level and coexistence probability given node-centrality measures that characterize specific patches. We show that both predator and prey species benefit from living in globally well-connected patches (i.e. with high closeness centrality). However, the maximum number of prey species is reached, on average, at lower closeness centrality levels than for predator species. Hence, prey species benefit from constraints imposed on species movement in fragmented landscapes since they can reproduce with a lesser risk of predation, and their need for using anti-predatory strategies decreases.authorCount :

    Prioritization of fish communities with a view to conservation and restoration on a large scale European basin, the Loire (France)

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    The hierarchical organization of important sites for the conservation or the restoration of fish communities is a great challenge for managers, especially because of financial or time constraints. In this perspective, we developed a methodology, which is easy to implement in different locations. Based on the fish assemblage characteristics of the Loire basin (France), we created a synthetic conservation value index including the rarity, the conservation status and the species origin. The relationship between this new synthetic index and the Fish-Based Index allowed us to establish a classification protocol of the sites along the Loire including fish assemblages to be restored or conserved. Sites presenting disturbed fish assemblages, a low rarity index, few threatened species, and a high proportion of non-native species were considered as important for the restoration of fish biodiversity. These sites were found mainly in areas where the assemblages are typical of the bream zone, e.g. with a higher number of eurytopic and limnophilic species. On the contrary, important sites for conservation were defined as having an important conservation potential (high RI, a lot of threatened species, and few nonnatives fish species) and an undisturbed fish assemblage similar to the expected community if habitats are undisturbed. Important sites for conservation were found in the Loire basin’s medium reaches which host assemblages typical for the grayling and the barbell zones, e.g. with a higher number of rheophilic species. The synthetic conservation value index could be adapted and completed with other criteria according to management priorities and capacities

    Two Separate Effects Contribute to Regulatory T Cell Defect in Systemic Lupus Erythematosus Patients and Their Unaffected Relatives

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    Forkhead box P3 (FoxP3)+ regulatory T cells (Tregs ) are functionally deficient in systemic lupus erythematosus (SLE), characterized by reduced surface CD25 [the interleukin (IL)-2 receptor alpha chain]. Low-dose IL-2 therapy is a promising current approach to correct this defect. To elucidate the origins of the SLE Treg phenotype, we studied its role through developmentally defined regulatory T cell (Treg ) subsets in 45 SLE patients, 103 SLE-unaffected first-degree relatives and 61 unrelated healthy control subjects, and genetic association with the CD25-encoding IL2RA locus. We identified two separate, uncorrelated effects contributing to Treg CD25. (1) SLE patients and unaffected relatives remarkably shared CD25 reduction versus controls, particularly in the developmentally earliest CD4+ FoxP3+ CD45RO- CD31+ recent thymic emigrant Tregs . This first component effect influenced the proportions of circulating CD4+ FoxP3high CD45RO+ activated Tregs . (2) In contrast, patients and unaffected relatives differed sharply in their activated Treg CD25 state: while relatives as control subjects up-regulated CD25 strongly in these cells during differentiation from naive Tregs , SLE patients specifically failed to do so. This CD25 up-regulation depended upon IL2RA genetic variation and was related functionally to the proliferation of activated Tregs , but not to their circulating numbers. Both effects were found related to T cell IL-2 production. Our results point to (1) a heritable, intrathymic mechanism responsible for reduced CD25 on early Tregs and decreased activation capacity in an extended risk population, which can be compensated by (2) functionally independent CD25 up-regulation upon peripheral Treg activation that is selectively deficient in patients. We expect that Treg -directed therapies can be monitored more effectively when taking this distinction into account.info:eu-repo/semantics/publishedVersio
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