274 research outputs found

    Structural and optical properties of TeO2- SeO2-Na2O glass system

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    50-6280 TeO2-(20-x) SeO2-xNa2O (where x = 0, 5, 10, 15, 20 mol %) ternary glass system have been successfully prepared by conventional melt-quenching method. The non-crystalline nature of the tested glass samples has been confirmed by X-ray diffraction. The structural transformation in the tested glass samples has been evaluated by measuring density (ρ), molar volume (VM), oxygen packing density (OPD) and oxygen molar volume (V0) values. The characteristic temperature of the glass system (glass transition,Tg, crystallization, Tc ) decreases with increasing Na2O content. Raman spectra show that addition of Na2O to TeO2 + SeO2 glass may result in cleavage of Te-O-Te and Se-O-Se linkages and formation of TeO3- and SeO3- terminal groups in the glass system. FTIR spectra show that the units of TeO4 units decrease and the units of TeO3 / TeO3+1 increase in the tested glass samples. The cut-off wavelength (λC), optical band gap (Eopt), refractive index (n), molar refraction (RM), metallization criterion (M), molar polarizability (αm), electronic polarizability of oxide ion (αo2-), optical basicity (Λ), Fermi energy (EF), dispersion energy (Ed), single oscillator energy (E0) and Urbach energy (ΔE) have been calculated from optical absorption spectra. The reflectivity of light and extinction coefficient (k) is used to find imaginary part of dielectric constant (Δi). The optical band gap energy and allowed transitions have been investigated using five methods; indirect, direct, indirect forbidden, direct forbidden and imaginary part of the dielectric constant. The optical band gap values of direct transition are in well agreement with the optical band values of an imaginary part of dielectric constant. The obtained optical band gap values decrease with increasing sodium oxide in the glass samples. Increase in Urbach energy values in the present glass system is due to an increase in the number of defects in the glass structure. The tested glass samples possess higher values of Urbach energy, molar electronic polarizability, and optical basicity. The excitation energy E0  decreases with the increase of Na2O content in the glass system

    Using spatial reference frames to generate grounded textual summaries of georeferenced data

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    Summarising georeferenced (can be identified according to it’s location) data in natural language is challenging because it requires linking events describing its nongeographic attributes to their underlying geography. This mapping is not straightforward as often the only explicit geographic information such data contains is latitude and longitude. In this paper we present an approach to generating textual summaries of georeferenced data based on spatial reference frames. This approach has been implemented in a data-to-text system we have deployed in the weather forecasting domain.

    Impaired contextual modulation of memories in PTSD: an fMRI and psychophysiological study of extinction retention and fear renewal

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    Post-traumatic stress disorder (PTSD) patients display pervasive fear memories, expressed indiscriminately. Proposed mechanisms include enhanced fear learning and impaired extinction or extinction recall. Documented extinction recall deficits and failure to use safety signals could result from general failure to use contextual information, a hippocampus-dependent process. This can be probed by adding a renewal phase to standard conditioning and extinction paradigms. Human subjects with PTSD and combat controls were conditioned (skin conductance response), extinguished, and tested for extinction retention and renewal in a scanner (fMRI). Fear conditioning (light paired with shock) occurred in one context, followed by extinction in another, to create danger and safety contexts. The next day, the extinguished conditioned stimulus (CS+E) was re-presented to assess extinction recall (safety context) and fear renewal (danger context). PTSD patients showed impaired extinction recall, with increased skin conductance and heightened amygdala activity to the extinguished CS+ in the safety context. However, they also showed impaired fear renewal; in the danger context, they had less skin conductance response to CS+E and lower activity in amygdala and ventral-medial prefrontal cortex compared with combat controls. Control subjects displayed appropriate contextual modulation of memory recall, with extinction (safety) memory prevailing in the safety context, and fear memory prevailing in the danger context. PTSD patients could not use safety context to sustain suppression of extinguished fear memory, but they also less effectively used danger context to enhance fear. They did not display globally enhanced fear expression, but rather showed a globally diminished capacity to use contextual information to modulate fear expression

    The Mind, the Brain, and the Law

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    In this chapter, we explore the potential influence that advances in neuroscience may have on legal decision makers and present the findings from some recent studies that probe folk intuitions concerning the relationships among neuroscience, agency, responsibility, and mental illness. We first familiarize the reader with some of the early research in experimental philosophy on people\u27s intuitions about agency and responsibility. Then, we focus on a more specific issue—namely, whether people respond to explanations of human behavior framed in neuroscientific terms differently than they respond to explanations framed in more traditional folk psychological terms. Next, we discuss some new findings which suggest that explanations of criminal behavior that are couched in neural terms appear to make people less punitive than explanations couched in mental terms, especially in the context of mental illness. Finally, we offer what we take to be the best explanation of these differences in people\u27s intuitions—namely, when people are presented with neural explanations of human behavior, they tend to think that the agent\u27s “deep self” (the values and beliefs the agent identifies with) is somehow left out of the causal loop or bypassed, which in turn mitigates the agent\u27s responsibility

    Mental Health Service Utilization before and after Receipt of a Service‐Connected Disability Award for PTSD: Findings from a National Sample

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146624/1/hesr12859.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146624/2/hesr12859-sup-0001-AppendixSA1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146624/3/hesr12859_am.pd

    Weakly Ionized Plasma Arc Heat Transfer Between Geometrically Dissimilar Electrodes

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    A set of self-consistent conservation equations for the charged particle densities and the temperatures in a weakl

    Design and Fabrication of Liquid Pressure Sensor using FBG Sensor through Seesaw Hinge Mechanism

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    Pressure sensors are used in various industrial applications assisting in preventing unintended disasters. This paper presents the design and fabrication of a novel Seesaw device incorporating a diaphragm and Fiber Bragg Grating (FBG) sensor to measure the pressure of liquids. The designed sensor has been tested in a static water column. The proposed design enables the user to easily make and modify the diaphragm based on the required pressure range without interfering with the FBG sensor. The developed pressure sensor produces improved accuracy and sensitivity to applied liquid pressure in both low and high-pressure ranges without requiring sophisticated sensor construction. A finite element analysis has been performed on the diaphragm and on the entire structure at 10 bar pressure. The deformation of the diaphragm is comparable to theoretical deformation levels. A copper diaphragm with a thickness of 0.25 mm is used in the experiments. All experiments are performed in the elastic region of the diaphragm. The sensor’s sensitivity as 19.244 nm/MPa with the linearity of 99.64% is obtained based on the experiments. Also, the proposed sensor’s performance is compared with recently reported pressure sensors.publishedVersio

    Expression of expanded FMR1-CGG repeats alters mitochondrial miRNAs and modulates mitochondrial functions and cell death in cellular model of FXTAS

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    Fragile X-associated tremor/ataxia syndrome (FXTAS) is a progressive neurodegenerative disorder caused by an expansion of 55 to 200 CGG repeats located within 5â€ČUTR of FMR1.These CGG repeats are transcribed into RNAs, which sequester several RNA binding proteins and alter the processing of miRNAs. CGG repeats are also translated into a toxic polyglycine-containing protein, FMRpolyG, that affects mitochondrial and nuclear functions reported in cell and animal models and patient studies. Nuclear-encoded small non-coding RNAs, including miRNAs, are transported to mitochondria; however, the role of mitochondrial miRNAs in FXTAS pathogenesis is not understood. Here, we analyzed mitochondrial miRNAs from HEK293 cells expressing expanded CGG repeats and their implication in the regulation of mitochondrial functions. The analysis of next generation sequencing (NGS) data of small RNAs from HEK293 cells expressing CGG premutation showed decreased level of cellular miRNAs and an altered pattern of association of miRNAs with mitochondria (mito-miRs). Among such mito-miRs, miR-320a was highly enriched in mitoplast and RNA immunoprecipitation of Ago2 (Argonaute-2) followed by Droplet digital PCR (ddPCR)suggested that miR-320a may form a complex with Ago2 and mitotranscripts. Finally, transfection of miR-320a mimic in cells expressing CGG permutation recovers mitochondrial functions and rescues cell death. Overall, this work reveals an altered translocation of miRNAs to mitochondria and the role of miR-320a in FXTAS pathology

    Mitochondria-Associated MicroRNAs in Rat Hippocampus Following Traumatic Brain Injury

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    Traumatic brain injury (TBI) is a major cause of death and disability. However, the molecular events contributing to the pathogenesis are not well understood. Mitochondria serve as the powerhouse of cells, respond to cellular demands and stressors, and play an essential role in cell signaling, differentiation, and survival. There is clear evidence of compromised mitochondrial function following TBI; however, the underlying mechanisms and consequences are not clear. MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally, and function as important mediators of neuronal development, synaptic plasticity, and neurodegeneration. Several miRNAs show altered expression following TBI; however, the relevance of mitochondria in these pathways is unknown. Here, we present evidence supporting the association of miRNA with hippocampal mitochondria, as well as changes in mitochondria-associated miRNA expression following a controlled cortical impact (CCI) injury in rats. Specifically, we found that the miRNA processing proteins Argonaute (AGO) and Dicer are present in mitochondria fractions from uninjured rat hippocampus, and immunoprecipitation of AGO associated miRNA from mitochondria suggests the presence of functional RNA-induced silencing complexes. Interestingly, RT-qPCR miRNA array studies revealed that a subset of miRNA is enriched in mitochondria relative to cytoplasm. At 12h following CCI, several miRNAs are significantly altered in hippocampal mitochondria and cytoplasm. In addition, levels of miR-155 and miR-223, both of which play a role in inflammatory processes, are significantly elevated in both cytoplasm and mitochondria. We propose that mitochondria-associated miRNAs may play an important role in regulating the response to TBI
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