52 research outputs found

    High-temperature molten salt thermal energy storage systems

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    The results of comparative screening studies of candidate molten carbonate salts as phase change materials (PCM) for advanced solar thermal energy storage applications at 540 to 870 C (1004 to 1600 F) and steam Rankine electric generation at 400 to 540 C (752 to 1004 F) are presented. Alkali carbonates are attractive as latent heat storage materials because of their relatively high storage capacity and thermal conductivity, low corrosivity, moderate cost, and safe and simple handling requirements. Salts were tested in 0.1 kWhr lab scale modules and evaluated on the basis of discharge heat flux, solidification temperature range, thermal cycling stability, and compatibility with containment materials. The feasibility of using a distributed network of high conductivity material to increase the heat flux through the layer of solidified salt was evaluated. The thermal performance of an 8 kWhr thermal energy storage (TES) module containing LiKCO3 remained very stable throughout 5650 hours and 130 charge/discharge cycles at 480 to 535 C (896 to 995 F). A TES utilization concept of an electrical generation peaking subsystem composed of a multistage condensing steam turbine and a TES subsystem with a separate power conversion loop was defined. Conceptual designs for a 100 MW sub e TES peaking system providing steam at 316 C, 427 C, and 454 C (600 F, 800 F, and 850 F) at 3.79 million Pa (550 psia) were developed and evaluated. Areas requiring further investigation have also been identified

    Recurrent neuroendocrine adenoma of the middle ear: A case report

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    Les historiens, qui sont rarement des oiseaux de trĂšs bon augure pour la vitalitĂ© des croyances qu’ils Ă©tudient, ont beaucoup Ă©crit, depuis les annĂ©es 1970, sur le purgatoire, ce troisiĂšme « lieu » de l’au-delĂ  catholique, situĂ© entre enfer et paradis. Support d’une dĂ©votion trĂšs populaire, il a connu en Europe trois pics successifs de popularitĂ©, Ă  la fin du Moyen Âge, au xviie et au xixe siĂšcles. Le dogme et la croyance ont ainsi puissamment structurĂ© dans la longue durĂ©e le rapport aux morts dans les sociĂ©tĂ©s de culture catholique, en leur confĂ©rant une « utilité » particuliĂšre, Ă  la fois matĂ©rielle, institutionnelle, pastorale et anthropologique, que cet article s’efforce d’explorer.Historians are people who rarely contribute to the continued vitality of the beliefs they study. Since the 1970’s they have written a lot about purgatory, the third place in the catholic beyond. This is situated in between hell and paradise. The belief was the basis of a very popular cult which peaked in popularity in three different periods, one at the end of the Middle Ages, another in the seventeenth and a third in the nineteenth century. The dogma and the belief in purgatory have thus for long periods powerfully structured the relation to the dead in catholic cultures and have given these a particular “usefulness” whether this concerns material, institutional, pastoral or anthropological aspects. The paper attempts to explore these issues

    Tracking the Expression of Excitatory and Inhibitory Neurotransmission-Related Proteins and Neuroplasticity Markers after Noise Induced Hearing Loss

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    Excessive exposure to loud noise can damage the cochlea and create a hearing loss. These pathologies coincide with a range of CNS changes including reorganisation of frequency representation, alterations in the pattern of spontaneous activity and changed expression of excitatory and inhibitory neurotransmitters. Moreover, damage to the cochlea is often accompanied by acoustic disorders such as hyperacusis and tinnitus, suggesting that one or more of these neuronal changes may be involved in these disorders, although the mechanisms remain unknown. We tested the hypothesis that excessive noise exposure increases expression of markers of excitation and plasticity, and decreases expression of inhibitory markers over a 32-day recovery period. Adult rats (n = 25) were monaurally exposed to a loud noise (16 kHz, 1/10th octave band pass (115 dB SPL)) for 1-hour, or left as non-exposed controls (n = 5). Animals were euthanased at either 0, 4, 8, 16 or 32 days following acoustic trauma. We used Western Blots to quantify protein levels of GABAA receptor subunit α1 (GABAAα1), Glutamic-Acid Decarboxylase-67 (GAD-67), N-Methyl-D-Aspartate receptor subunit 2A (NR2A), Calbindin (Calb1) and Growth Associated Protein 43 (GAP-43) in the Auditory Cortex (AC), Inferior Colliculus (IC) and Dorsal Cochlear Nucleus (DCN). Compared to sham-exposed controls, noise-exposed animals had significantly (p<0.05): lower levels of GABAAα1 in the contralateral AC at day-16 and day-32, lower levels of GAD-67 in the ipsilateral DCN at day-4, lower levels of Calb1 in the ipsilateral DCN at day-0, lower levels of GABAAα1 in the ipsilateral AC at day-4 and day-32. GAP-43 was reduced in the ipsilateral AC for the duration of the experiment. These complex fluctuations in protein expression suggests that for at least a month following acoustic trauma the auditory system is adapting to a new pattern of sensory input

    Recent developments in genetics and medically assisted reproduction : from research to clinical applications

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    Two leading European professional societies, the European Society of Human Genetics and the European Society for Human Reproduction and Embryology, have worked together since 2004 to evaluate the impact of fast research advances at the interface of assisted reproduction and genetics, including their application into clinical practice. In September 2016, the expert panel met for the third time. The topics discussed highlighted important issues covering the impacts of expanded carrier screening, direct-to-consumer genetic testing, voiding of the presumed anonymity of gamete donors by advanced genetic testing, advances in the research of genetic causes underlying male and female infertility, utilisation of massively parallel sequencing in preimplantation genetic testing and non-invasive prenatal screening, mitochondrial replacement in human oocytes, and additionally, issues related to cross-generational epigenetic inheritance following IVF and germline genome editing. The resulting paper represents a consensus of both professional societies involved.Peer reviewe
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