498 research outputs found
Identification of a rhythmic firing pattern in the enteric nervous system that generates rhythmic electrical activity in smooth muscle
The enteric nervous system (ENS) contains millions of neurons essential for organization of motor behavior of the intestine. It is well established that the large intestine requires ENS activity to drive propulsive motor behaviors. However, the firing pattern of the ENS underlying propagating neurogenic contractions of the large intestine remains unknown. To identify this, we used high-resolution neuronal imaging with electrophysiology from neighboring smooth muscle. Myoelectric activity underlying propagating neurogenic contractions along murine large intestine [also referred to as colonic migrating motor complexes, (CMMCs)] consisted of prolonged bursts of rhythmic depolarizations at a frequency of ∼2 Hz. Temporal coordination of this activity in the smooth muscle over large spatial fields (∼7 mm, longitudinally) was dependent on the ENS. During quiescent periods between neurogenic contractions, recordings from large populations of enteric neurons, in mice of either sex, revealed ongoing activity. The onset of neurogenic contractions was characterized by the emergence of temporally synchronized activity across large populations of excitatory and inhibitory neurons. This neuronal firing pattern was rhythmic and temporally synchronized across large numbers of ganglia at ∼2 Hz. ENS activation preceded smooth muscle depolarization, indicating rhythmic depolarizations in smooth muscle were controlled by firing of enteric neurons. The cyclical emergence of temporally coordinated firing of large populations of enteric neurons represents a unique neural motor pattern outside the CNS. This is the first direct observation of rhythmic firing in the ENS underlying rhythmic electrical depolarizations in smooth muscle. The pattern of neuronal activity we identified underlies the generation of CMMCs
Implicações das políticas de avaliação externa para a Educação Matemática
A partir da década de 1990, no Brasil, diversas reformas educacionais foram levadas a cabo, com viés empresarial e neoliberal, subvertendo-se os fins da educação para favorecer a ação do capital em oposição à formação para a emancipação humana. Essas reformas intensificaram os mecanismos de controle sobre as escolas e tem usado a avaliação em larga escala como mecanismo indutor de qualidade, entendida como atributo universalmente aceito; ranqueamentos se sucedem e tem gerado formas de responsabilizar cada vez mais os atores escolares (Freitas, 2012; Ravitch, 2011). Como consequência, currículos têm sido delineados a partir das matrizes de referência dos testes padronizados, práticas têm sido conformadas para treinar estudantes para os testes, há aberturas para fraudes em exames, competições entre escolas e docentes entre outros (Freitas, 2012; Ravitch, 2011). Este trabalho visa discutir as implicações do modelo de avaliação em larga escala ora hegemônico para a educação matemática, tendo em vista os percalços acima citados. Tais repercussões não são apenas tangentes à educação matemática, pois nesse cenário, práticas alternativas e preocupadas com uma educação matemática socialmente relevante e emancipatória do indivíduo (Skovsmose, 2014) também podem estar afetadas esmaecendo os mecanismos de luta por uma formação humana
Cenários para investigação como ferramenta de avaliação: uma discussão
Neste artigo, apresenta-se uma discussão no campo teórico sobre a possibilidade da utilização dos cenários para investigação como ferramenta de avaliação. Nesse sentido, são contrastadas formas de se conceber o ensino e a avaliação em matemática. Procura-se enfatizar a relação do modelo ora hegemônico de avaliação com o ensino tradicional de matemática, bem como a proposta dos cenários para investigação com uma concepção mais formativa de avaliação dentro de um ensino mais preocupado com uma formação crítica dos indivíduos. Assim, tal estratégia é percebida como um modelo de avaliação que se distancia da medida do desempenho, classificação e seleção dos alunos, onde o erro é fonte de punição e não de reflexão ou investigação por parte do professor. Espera-se que essa discussão possa fomentar espaços de reflexão sobre as práticas de ensino e sobre as práticas avaliativas de professores de Matemática
Kritik Atas Kontroversi Hadis Tentang Aurat Laki-laki
This article discusses two seemingly contradictory hadith, is t tradition of male genitalia. There is a hadith which states that the thigh is including for male genitalia, so that should be covered, and there is another tradition that informs that the Prophet ever -in some circumstances-lifting clothes so it looks his thigh. This seems contradictory hadith then tried to reconcile with utilizing the science of hadith traditions that are concerned in this matter, namely mukhtalif al-hadîth. By the several methods of settlement, the authors take the methods of al-jam‘. Under this settlement, it can be seen that the two traditions is basically not contradictory, both are maqbûl and ma‘mul bih, prohibition to open thighs is makrûh tanzîh arbitrate and be open is allowed if there is an intent
Successful treatment of Trichosporon asahii fungemia with isavuconazole in a patient with hematologic malignancies
International audienceTrichosporon spp. are yeast-like microorganisms responsible for skin, urinary, pulmonary, or bloodstream infections. Due to intrinsic resistance to echinocandins, poor susceptibility to polyenes, and preferred occurrence in immunocompromised patients, such infections are often of poor prognosis. Yet no consensual therapeutic guidelines are presently available. Several clinical cases of Trichosporon infections have been successfully treated with azole therapy, including voriconazole which appeared frequently effective against Trichosporon both in vitro and in vivo. However, the low efficacy associated with some Trichosporon genotypes, complex pharmacokinetics, and the side effects of voriconazole represent limitations for its use and has prompted a search for other therapeutic options. Here, we report a case of T. asahii fungemia in a patient with B-cell acute lymphoblastic leukemia which was successfully treated with isavuconazole consecutive to stopping voriconazole therapy due to severe side effects. This observation suggests that isavuconazole with a similar spectrum to voriconazole, fewer pharmacology interactions, and side effects may be considered as a valuable therapeutic option against Trichosporon infections
Common occurrence of Cryptosporidium hominis in asymptomatic and symptomatic calves in France
International audienceSymptomatic infection by the Apicomplexan Cryptosporidium spp. is presently considered the most frequent parasitic cause of acute diarrhea in both humans (especially severe in immunocompromised individuals and infants in both developed and developing countries) and cattle (calves), while asymptomatic infections are less often documented. Cryptosporidium (C.) hominis once considered to be restricted to humans accounts for the majority of pediatric cases in several countries. C. parvum can also infect cattle as well as C. bovis, C. andersoni, and C. ryanae. Recently, cattle C. hominis cryptosporidiosis has been reported, suggesting that the presence of C. hominis in calves was previously underestimated. The aim of this work was to characterize Cryptosporidium spp. infection in both asymptomatic and symptomatic dairy and beef calves from Metropolitan France. From February to November 2015, C. parvum or C. hominis infected calves were detected in farms from 5 geographic regions of France. Surprisingly, C. hominis was present in about one fifth of Cryptosporidium spp. infected calves, and exhibited genotypes which were previously reported in human and nonhuman primate. Further investigations are aimed at documenting direct or indirect C. hominis transmissions between and among livestock and humans
AS AVALIAÇÕES EXTERNAS E A EDUCAÇÃO MATEMÁTICA CRÍTICA: CONEXÕES E IMPASSES
O presente artigo tem como objetivo desvelar as possíveis conexões entre a Educação Matemática Crítica e a problemática das avaliações externas em larga escala no Brasil, tendo como base, a revisão da literatura da área. Tem-se que, atualmente, os resultados de exames de avaliações em larga escala e o fluxo dos estudantes são utilizados para compor índices de qualidade da educação, baseados em lógicas de eficiência e produtividade, mais próximos de ideais mercadológicos do que educacionais. Essa nova racionalidade tem influenciado o cotidiano escolar, por meio da padronização de currículos e práticas, desmoralizando professores e escolas, potencializando o ensino tradicional de Matemática e o absolutismo burocrático, em detrimento de uma Educação Matemática Crítica (EMC), por meio da criação de consensos e de ideologias da certeza. Nesse sentido, a prática calcada nos pressupostos da EMC pode configurar-se como momento de resistência por parte dos professores de Matemática, incentivar a busca pelo fortalecimento do coletivo escolar e a restituição de processos mais democráticos dentro e fora da escola (sobretudo no que diz respeito à construção de critérios de avaliação do ensino) para que se apresentem alternativas ao modelo tradicional de ensino da Matemática
Caching Using Software-Defined Networking in LTE Networks
Research ReportThe data consumption is increasing rapidly in mobile net- works. The cost of network infrastructure is increasing, which will lead to an ”end of profit” within next few years. Thus, mobile operators require technology that allows in- creasing the network capacity within low network costs. There- fore, using caching is the most evident solution to be used in their backhaul networks. However, the current architec- ture of LTE network does not provide sucient flexibility to place the caches in the most optimal locations. The current work on Software-Defined Networking in Evolved Packet Core virtualization has enabled us to integrate dy- namically the caching functionality in a LTE network and improve the caching system performance. In this paper, we present the solution we designed for this aim based on Soft- ware Defined Networking technology. Moreover, we developa testbed for the proof-of-concept and we present perfor- mance analysis of this solution
Altered Cortico-Striatal–Thalamic Connectivity in Relation to Spatial Working Memory Capacity in Children with ADHD
Introduction: Attention deficit hyperactivity disorder (ADHD) captures a heterogeneous group of children, who are characterized by a range of cognitive and behavioral symptoms. Previous resting-state functional connectivity MRI (rs-fcMRI) studies have sought to understand the neural correlates of ADHD by comparing connectivity measurements between those with and without the disorder, focusing primarily on cortical–striatal circuits mediated by the thalamus. To integrate the multiple phenotypic features associated with ADHD and help resolve its heterogeneity, it is helpful to determine how specific circuits relate to unique cognitive domains of the ADHD syndrome. Spatial working memory has been proposed as a key mechanism in the pathophysiology of ADHD. Methods: We correlated the rs-fcMRI of five thalamic regions of interest (ROIs) with spatial span working memory scores in a sample of 67 children aged 7–11 years [ADHD and typically developing children (TDC)]. In an independent dataset, we then examined group differences in thalamo-striatal functional connectivity between 70 ADHD and 89 TDC (7–11 years) from the ADHD-200 dataset. Thalamic ROIs were created based on previous methods that utilize known thalamo-cortical loops and rs-fcMRI to identify functional boundaries in the thalamus. Results/Conclusion: Using these thalamic regions, we found atypical rs-fcMRI between specific thalamic groupings with the basal ganglia. To identify the thalamic connections that relate to spatial working memory in ADHD, only connections identified in both the correlational and comparative analyses were considered. Multiple connections between the thalamus and basal ganglia, particularly between medial and anterior dorsal thalamus and the putamen, were related to spatial working memory and also altered in ADHD. These thalamo-striatal disruptions may be one of multiple atypical neural and cognitive mechanisms that relate to the ADHD clinical phenotype
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