32 research outputs found

    Deciphering the functional role of spatial and temporal muscle synergies in whole-body movements

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    International audienceVoluntary movement is hypothesized to rely on a limited number of muscle synergies, the recruitment of which translates task goals into effective muscle activity. In this study, we investigated how to analytically characterize the functional role of different types of muscle synergies in task performance. To this end, we recorded a comprehensive dataset of muscle activity during a variety of whole-body pointing movements. We decomposed the electromyographic (EMG) signals using a space-by-time modularity model which encompasses the main types of synergies. We then used a task decoding and information theoretic analysis to probe the role of each synergy by mapping it to specific task features. We found that the temporal and spatial aspects of the movements were encoded by different temporal and spatial muscle synergies, respectively, consistent with the intuition that there should a correspondence between major attributes of movement and major features of synergies. This approach led to the development of a novel computational method for comparing muscle synergies from different participants according to their functional role. This functional similarity analysis yielded a small set of temporal and spatial synergies that describes the main features of whole-body reaching movements

    Track D Social Science, Human Rights and Political Science

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

    Pathogens, parasites, and parasitoids associated with bumble bees (Bombus spp.) from Uruguay

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    As elsewhere in the world, bumble bees play a vital role as pollinators in Uruguay, but knowledge on their health status is still limited. Between September 2012 and May 2013, 403 adult individuals of the two speciesof Bombus known for the country (Bombus atratus , Bombus bellicosus ) were collected in six localities.We found that 177 (119 B. atratus, 58 B. bellicosus ) were harboring one or two types of pathogens, parasites, or parasitoids.Identification of these natural enemies carried out by morphological or molecular procedures revealed the presence of two species of Microsporidia [Nosema ceranae (prevalence: 18.2 % in B. atratus; 44.9 % in B. bellicosus ),Tubulinosema pampeana (prevalence: 13 % in B. atratus )], two species of Nematoda [Sphaerularia bombi (prevalence: 40.4 % in B. atratus; 40% in B. bellicosus ) and an unidentified Mermithidae (prevalence: 0.8 % inB. bellicosus )], and one species of Diptera parasitoid (prevalence: 3.2 % in B. atratus ; 4.2 % in B. bellicosus ). Except N. ceranae , none of the other species have been previously reported in Uruguay.Fil: Plischuk, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Salvarrey, Sheena. Universidad de la República. Facultad de Ciencias; UruguayFil: Arbulo, Natalia. Universidad de la República; UruguayFil: Santos, Estela. Universidad de la República. Facultad de Ciencias; UruguayFil: Skevington, Jeffrey H.. Canadian National Collection of Insects; CanadáFil: Kelso, Scott. Canadian National Collection of Insects; CanadáFil: Revainera, Pablo Damian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Maggi, Matías Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata; ArgentinaFil: Invernizzi, Ciro. Universidad de la República. Facultad de Ciencias; UruguayFil: Lange, Carlos Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentin

    Integração de três conceitos: função executiva, memória de trabalho e aprendizado

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    O presente artigo discute o conceito de função executiva enquanto um processo de integração temporal, envolvendo funções como o ajuste preparatório, o controle inibitório e a memória de trabalho. Em seguida questiona o modelo multicomponente de Baddeley para a memória de trabalho e propõe uma nova classificação da função executiva que engloba os modelos de Fuster e de Baddeley. Finalmente revisita o conceito neurobiológico de aprendizado e sugere uma abordagem para se avaliar os déficits de aprendizagem que leve em conta a função executiva como a pedra angular do processo cognitivo

    Inflammatory responses of a human keratinocyte cell line to 10 nm citrate- and PEG-coated silver nanoparticles

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    Silver nanoparticles (AgNPs) are among the most commonly used engineered NPs and various commercially available products are designed to come in direct contact with the skin (wound dressings, textiles, creams, among others). Currently, there is limited understanding of the influence of coatings on the toxicity of AgNPs and in particular their ability to impact on AgNP's mediated inflammatory responses. As AgNPs are often stabilized by different coatings, including citrate and polyethyleneglycol (PEG), in this study we investigate the influence of citrate (Cit10) or PEG (PEG10) coatings to 10 nm AgNP on skin, using human HaCaT keratinocytes. AgNPs cytotoxicity and inflammatory response (nuclear factor (NF)-kappa B induction and cytokine production) of HaCaT were assessed after in vitro exposure to 10 and 40 A mu g/mL after 4, 24, and 48 h. Results showed that although both types of coated AgNPs decreased cell proliferation and viability, Cit10 AgNPs were more toxic. NF-kappa B inhibition was observed for the highest concentration (40 A mu g/mL) of PEG10 AgNPs, and the putative link to early apoptotic pathways observed in these cells is discussed. No production of IL-1 beta, IL-6, IL-10, and TNF alpha was stimulated by AgNPs. Furthermore, Cit10 and PEG10 AgNPs decreased the release of MCP-1 by HaCaT cells after 48 h of exposure. As cytokines are vital for the immunologic regulation in the human body, and it is demonstrated that they may interfere with NPs, more research is needed to understand how different AgNPs affect the immune system

    Febre amarela Yellow fever

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    A febre amarela é doenca infecciosa não-contagiosa causada por um arbovírus mantido em ciclos silvestres em que macacos atuam como hospedeiros amplificadores e mosquitos dos gêneros Aedes na África, e Haemagogus e Sabethes na América, são os transmissores. Cerca de 90% dos casos da doença apresentam-se com formas clínicas benignas que evoluem para a cura, enquanto 10% desenvolvem quadros dramáticos com mortalidade em torno de 50%. O problema mostra-se mais grave em África onde ainda há casos urbanos. Nas Américas, no período de 1970-2001, descreveram-se 4.543 casos. Os países que mais diagnosticaram a doença foram o Peru (51,5%), a Bolívia (20,1%) e o Brasil (18,7%). Os métodos diagnósticos utilizados incluem a sorologia (IgM), isolamento viral, imunohistoquímica e RT-PCR. A zoonose não pode ser erradicada, mas, a doença humana é prevenível mediante a vacinação com a amostra 17D do vírus amarílico. A OMS recomenda nova vacinação a cada 10 anos. Neste artigo são revistos os principais conceitos da doença e os casos de mortes associados à vacina.<br>Yellow fever is an infectious and non-contagious disease caused by an arbovirus, the yellow fever virus. The agent is maintained in jungle cycles among primates as vertebrate hosts and mosquitoes, especially Aedes in Africa, and Haemagogus and Sabethes in America. Approximately 90% of the infections are mild or asymptomatic, while 10% course to a severe clinical picture with 50% case-fatality rate. Yellow fever is largely distributed in Africa where urban epidemics are still reported. In South America, between 1970-2001, 4,543 cases were reported, mostly from Peru (51.5%), Bolivia (20.1%) and Brazil (18.7%). The disease is diagnosed by serology (detection of IgM), virus isolation, immunohistochemistry and RT-PCR. Yellow fever is a zoonosis and cannot be eradicated, but it is preventable in man by using the 17D vaccine. A single dose is enough to protect an individual for at least 10 years, after which revaccination is recommended. In this paper, the main concepts about yellow fever as well as the fatal adverse effects of the vaccine are updated
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