191 research outputs found

    Nonparametric Weight Initialization of Neural Networks via Integral Representation

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    A new initialization method for hidden parameters in a neural network is proposed. Derived from the integral representation of the neural network, a nonparametric probability distribution of hidden parameters is introduced. In this proposal, hidden parameters are initialized by samples drawn from this distribution, and output parameters are fitted by ordinary linear regression. Numerical experiments show that backpropagation with proposed initialization converges faster than uniformly random initialization. Also it is shown that the proposed method achieves enough accuracy by itself without backpropagation in some cases.Comment: For ICLR2014, revised into 9 pages; revised into 12 pages (with supplements

    Analysis of Manuals about Education for Disaster Prevention in Schools

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    Schools have recently made efforts to include education for disaster prevention. Teachers have practices lessons using teaching materials as authoritative guidelines for disaster prevention education; thus, by understanding the basis of learning, they are engaging in educational practice. The purpose of this study is to clarify the contents and practical use of educational manuals for disaster prevention education in schools. Additional purpose is the manual contents were analyzed from five perspectives that should be examined in education for disaster prevention (i.e., the original goals, topographical characteristics of the area and that of past disasters, sustainability, the role of social studies and geography, and child development stages). Four items comprised most of the disaster prevention education manualsā€™ contents: i.e., the disaster prevention education aim, characteristics and consideration of disaster prevention educational practices, or examples of situations during a natural disaster. The result of analysis show that some manuals present topographical materials and past disasters in each local area. However, specific contents of disaster were different for each prefecture. Furthermore, there were very few contents about sustainability. To overcome this problem, it is necessary to improve teaching materials for disaster prevention education that understands the regional circumstances such as dangerous areas and includes an education for sustainable development perspective

    Environmental Study in Elementary Geography in the United Kingdom by Analysis of Geographical Schoolā€™s Textbook

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    Environmental education in elementary school in Japan is defined as ā€œMoral Educationā€ by the national curriculum. However, environmental education is one of the most important contents in geographical education. This study aims to clarify the contents in elementary geography in the United Kingdom by analyzing the elementary geographical textbook, in order to develop the basic environmental geographical education. And also we want to know how to educate environmental study in elementary school and how to improve it, from the view point of ESD (ā€œEducation for Sustainable Developmentā€). Analyzed the elementary geographical textbooks, we find that it is effective for environmental education in UK to use various activities. All geographical textbooks foster problem solving abilities by using geographical activities and rearing scientific thinking

    1Ī±,25-Dihydroxyvitamin D3 enhances cerebral clearance of human amyloid-Ī² peptide(1-40) from mouse brain across the blood-brain barrier

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    <p>Abstract</p> <p>Background</p> <p>Cerebrovascular dysfunction has been considered to cause impairment of cerebral amyloid-Ī² peptide (AĪ²) clearance across the blood-brain barrier (BBB). Further, low levels of vitamin D are associated with increased risk of Alzheimer's disease, as well as vascular dysfunction. The purpose of the present study was to investigate the effect of 1Ī±,25-dihydroxyvitamin D<sub>3 </sub>(1,25(OH)<sub>2</sub>D3), an active form of vitamin D, on cerebral AĪ² clearance from mouse brain.</p> <p>Methods</p> <p>The elimination of [<sup>125</sup>I]hAĪ²(1-40) from mouse brain was examined by using the Brain Efflux Index method to determine the remaining amount of [<sup>125</sup>I]hAĪ²(1-40) radioactivity after injection into the cerebral cortex. [<sup>125</sup>I]hAĪ²(1-40) internalization was analyzed using conditionally immortalized mouse brain capillary endothelial cells (TM-BBB4).</p> <p>Results</p> <p>Twenty-four hours after intraperitoneal injection of 1,25(OH)<sub>2</sub>D3 (1 Ī¼g/mouse), [<sup>125</sup>I]hAĪ²(1-40) elimination from mouse brain was increased 1.3-fold, and the level of endogenous AĪ²(1-40) in mouse brain was reduced. These effects were observed at 24 h after i.p. injection of 1,25(OH)<sub>2</sub>D3, while no significant effect was observed at 48 or 72 h. Vitamin D receptor (VDR) mRNA was detected in mouse brain capillaries, suggesting that 1,25(OH)<sub>2</sub>D3 has a VDR-mediated genomic action. Furthermore, forskolin, which activates mitogen-activated protein kinase kinase (MEK), enhanced [<sup>125</sup>I]hAĪ²(1-40) elimination from mouse brain. Forskolin also enhanced [<sup>125</sup>I]hAĪ²(1-40) internalization in TM-BBB4 cells, and this enhancement was inhibited by a MEK inhibitor, suggesting involvement of non-genomic action.</p> <p>Conclusions</p> <p>The active form of vitamin D, 1,25(OH)<sub>2</sub>D3, appears to enhance brain-to-blood AĪ²(1-40) efflux transport at the BBB through both genomic and non-genomic actions. Compounds activating these pathways may be candidate agents for modulating AĪ²(1-40) elimination at the BBB.</p

    Tests of human auditory temporal resolution: preliminary investigation of ZEST parameters for amplitude modulation detection

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    Auditory temporal resolution plays a critical role in the everyday experience of listening to complex acoustic patterns. Amplitude modulation detection thresholds are widely used to measure auditory temporal resolution. In an attempt to develop a standardized clinical test of auditory temporal resolution, we used ZEST (Zippy Estimation by Sequential Testing, a Bayesian threshold estimation procedure, to measure amplitude modulation detection thresholds. ZEST utilizes prior knowledge about a listenerā€™s thresholds, as represented by a probability density function of the thresholds, and psychometric functions of the listenerā€™s responses. This paper reports a preliminary study in which ZEST parameters that could be used for measurements of amplitude modulation detection thresholds were sought. For this purpose, we created histograms of the detection thresholds for a wide range of modulation frequencies, measured the psychometric functions of amplitude modulation detection, and performed computer simulations of ZEST threshold estimation. The results suggested that, with appropriately-set parameters, ZEST allows for the accurate estimation of amplitude modulation detection thresholds within 20 trials

    Day-to-Day Variation in the Hoffmann Reflex in Females

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    The present study aimed to investigate changes in the Hoffmann reflex (H-reflex) at the same time on different days and to compare the findings between genders. Four males and five females in healthy subjects agreed to participate in the study and provided informed consent. All subjects were nonsmokers, and none of the females were consuming any oral contraceptives. The H-reflex was elicited in the right soleus muscle by constant current stimulation of the tibial nerve in the popliteal fossa with the subjects in the prone position. As a reference, the maximal amplitude of the H-wave relative to that of the M-wave (Hmax/Mmax) was measured to determine changes in Ī±-motoneuron excitability. Hmax/Mmax of 6 to 9 trials and was represented by the coefficient of variation (CV). The CV of Hmax/Mmax in females was significantly higher than that in males. The level of Hmax/Mmax for males was highly reproducible, suggesting that fewer factors alter Ī±-motoneuron excitability in males compared with those in females. Several female subjects experienced symptoms of depression and suffered from body and menstrual pain. Variations in Hmax/Mmax values were considerably greater for females than for males, suggesting that the Ī±-motoneuron might be influenced by the menstrual cycle phase as well as by individual differences
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