1,060 research outputs found

    Coarse--graining, fixed points, and scaling in a large population of neurons

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    We develop a phenomenological coarse--graining procedure for activity in a large network of neurons, and apply this to recordings from a population of 1000+ cells in the hippocampus. Distributions of coarse--grained variables seem to approach a fixed non--Gaussian form, and we see evidence of scaling in both static and dynamic quantities. These results suggest that the collective behavior of the network is described by a non--trivial fixed point

    A study of clinicoradiological and functional outcomes of intramedullary nailing in diaphyseal radius ulna fractures

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    Background: The aim of this study was to evaluate the results of intramedullary nailing in diaphyseal fractures of radius and ulna in age group of 10 to 49 years and to understand its clinicoradiological and functional results.Methods: This is a retrospective case series study of forearm bone fractures and the selected management for the same over a period of 3 years. We chose the cases in which intramedullary nailing was the treatment modality which were followed up over a period of minimum 6 months. Patients with galeazzi variety, monteggia variety, pathological fracture or non-union after previous surgery were excluded. The outcomes were then evaluated with disabilities of the arm, shoulder and hand (DASH) score, Green and O’Brien score, and Grace and Eversmann functional outcome score.Results: Of the 22 patients, 10 patients had excellent functional outcome according to Grace and Eversmann score, 7 patients had good outcome, 4 patients had acceptable while 1 was unacceptable. Green and O’Brien also had similar results, except that patients among fair category were 3 and poor category were 3. The mean DASH score was 16.2.Conclusions: This study shows that closed method for fixation by intramedullary nailing of both bone forearm fractures leads to excellent to good functional outcomes (according to DASH score, Green and O Brien, and Grace and Eversmann score) with less complications. In 6 months follow up x ray there is radiological union in all cases with no angulation, malunion or non-union.

    Baby Steps toward Meeting Engineering-rich Science Standards: Approaches and Results from a Short What is Engineering? Course for K-5 Pre-service Teachers (Work in Progress)

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    Elementary teacher preparation programs are generally tightly packed, with limited room for additional coursework. As states adopt Next Generation Science Standards (NGSS ), the need for teacher education programs to provide meaningful exposure to engineering is growing, and a multitude of approaches can be taken to meet this need. While the topics of engineering and engineering design are typically incorporated into science teaching methods courses, this research presents an alternative approach where we expose elementary pre-service teachers to engineering prior to or concurrently with enrollment in their methods courses. Specifically, we describe here our efforts in building a 12-contact-hour non-credit short course – based upon NGSS-aligned learning outcomes – that was delivered to 10 students in fall 2016. We provide details on our approaches, including examples used in the course, and explain our decision to offer this as a short course instead of a full-semester course. We also report on results from the pre- and post-surveys which we used to assess student learning in the course, and to understand what aspects of the course needed improvement

    Cultivating equality: delivering just and sustainable food systems in a changing climate

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    T oday, the world faces a greater challenge perhaps than ever before: tackling hunger and malnutrition in the face of climate change and increasing natural resource scarcity. Civil society, governments, researchers, donors, and the private sector are simultaneously debating and collaborating to find solutions. But the dialogue is over-emphasizing food production. Improving yields is important, particularly in places where there is not enough food or where food producers live in poverty. But simply producing more is not enough to tackle hunger. Furthermore, acknowledging that lack of food is not the sole cause of hunger is important. Inequality shapes who has access to food and the resources to grow it and buy it. It governs who eats first and who eats worst. Inequality determines who can adapt more readily to a changing climate. Hunger and poverty are not an accident – they are the result of social and economic injustice and inequality at all levels, from household to global. The reality of inequality is no truer for anyone than it is for women – half the world’s population, with far less than their fair share of the world’s resources. If we are to achieve the new Sustainable Development Goal of ending hunger by 2030, we must address the underlying inequalities in food systems. In a changing climate, agriculture and food systems must be sustainable and productive – but our efforts cannot end there. They must be profitable for those for whom it is a livelihood; they must be equitable, to facilitate a level playing field in the market, to secure rights to resources for food producers, and to ensure access to nutritious food for all; they must be resilient to build the capacity of populations vulnerable to economic shocks, political instability, and increasing, climate-induced natural hazards to recover and still lift themselves out of poverty

    Real-Time Magnetic Resonance Imaging to Study Orthostatic Intolerance Mechanisms in Human Beings: Proof of Concept

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    Background:Discerning the mechanisms driving orthostatic symptoms in human beings remains challenging. Therefore, we developed a novel approach combining cardiac and cerebral real‐time magnetic resonance imaging, beat‐to‐beat physiological monitoring, and orthostatic stress testing through lower‐body negative pressure (LBNP). We conducted a proof‐of‐concept study in a patient with severe orthostatic hypotension.Methods and Results:We included a 46‐year‐old man with pure autonomic failure. Without and during −30 mmHg LBNP, we obtained 3T real‐time magnetic resonance imaging of the cardiac short axis and quantitative flow measurements in the pulmonary trunk and middle cerebral artery. Blood pressure was 118/74 mmHg during supine rest and 58/35 mmHg with LBNP. With LBNP, left ventricular stroke volume decreased by 44.6%, absolute middle cerebral artery flow by 37.6%, and pulmonary trunk flow by 40%.Conclusions:Combination of real‐time magnetic resonance imaging, LBNP, and continuous blood pressure monitoring provides a promising new approach to study orthostatic intolerance mechanisms in human beings
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