1,423 research outputs found

    Infinite charge mobility in muscovite at 300K

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    Evidence is presented for infinite charge mobility in natural crystals of muscovite mica at room temperature. Muscovite has a basic layered structure containing a flat monatomic sheet of potassium sandwiched between mirror silicate layers. It is an excellent electrical insulator. Studies of defects in muscovite crystals indicated that positive charge could propagate over great distances along atomic chains in the potassium sheets in absence of an applied electric potential. The charge moved in association with anharmonic lattice excitations that moved at about sonic speed and created by nuclear recoil of the radioactive isotope K40. This was verified by measuring currents passing through crystals when irradiated with energetic alpha particles at room temperature. The charge propagated more than 1000 times the range of the alpha particles of average energy and 250 times the range of channelling particles of maximum energy. The range is limited only by size of the crystal.Comment: 6 pages, 8 figure

    Responses of Agronomically Important Tropical Crops to the Application of Brassinosteroid

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    Brassinosteroids (Br) have been shown to favor the growth and reproduction of crops under adverse environmental conditions, which negatively affect their growth and production. In order to solve some of the problems in the field with various perennial crops, the application of a homobrassinolide (HBr) (CIDEF-4) has been investigated under in vitro and ex vitro conditions to evaluate growth at different concentrations in Musa spp. L. and Saccharum officinarum L and in the field with foliar applications in Theobroma cacao L, Mangifera indica L and Coffea arabica L. to evaluate yield and quality of fruits. Morphological and physiological yield components were recorded. The results indicate in the in vitro evaluations, increased regrowth height and ex vitro differences in growth are improved by increasing the number of applications. In cocoa and coffee plants, flowering and yield are influenced. The high concentrations applied did not necessarily increase the crop yield or the combination with potassium nitrate. In mango, the quality of the fruits was better when applying the HBr alone or in combination with nitrate in fruit firmness, and total soluble solids improved

    Hidrotubación: técnica combinada: cirugía más fluidos intrauterino

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    The objective of this work is to expose the medical community a technique of Hidrotubation less aggressive, more economical and practical to solve infertility caused by tubal obstruction postsurgical. For manyyears dating back to the last century physicians have been practicing some surgical techniques and theapplication of intrauterine substances in order to “un-cork” the(s) tube(s) of Fallopian with flattering resultsslightly. The technique consists of a combined procedure of pelvic laparotomy and intrauterine applicationvaginally of distilled water, corticosteroids and mucolytic that at the time this giving successful outcomesfor the treatment of tubal infertility cause. The innovations that have been demonstrated in this work arethe product of many years of persistent practice and private experience in the treatment of obstructivetubal pathology strictly in the surgical field and the drug aspect will be a significant contribution to the improvement of the technique hydrotubation in our midst. In this work I expose a case of post-surgical tubalobstruction was resolved by applying this technique conservative and had a happy ending, sought successpregnancy, live birth in good condition, happiness mother and partner.With this report, also demonstrate the benefit post - surgical instruments when applying less material in theregion is operated and a matter of adaptation of the technique.El presente trabajo tiene como objetivo, exponer a la comunidad médica una técnica de Hidrotubación, menos agresiva, más práctica y económica para resolver la infertilidad por causa de obstrucción tubárica postquirúrgica. Desde hace muchos años que datan del siglo pasado se han venido practicando algunas técnicas quirúrgicas y la aplicación de sustancias intrautero con el fin de “destapar” la(s) Trompa(s) de Falopio con resultados levemente halagadores. La técnica consiste en un procedimiento combinado de la parotomía pélvica y la aplicación intrauterina por vía vaginal de agua destilada, corticoides y mucolítico que al momento está dando resultados exitosos para el tratamiento de la infertilidad de causa tubárica. Las innovaciones que se han demostrado en este trabajo son producto de muchos años de práctica perseverante y experiencia privada en el tratamiento de la patología tubárica obstructiva en el campo quirúrgico estrictamente y en el aspecto medicamentoso que servirá de importante aporte al mejoramiento de la técnica de hidrotubación en nuestro medio. En este trabajo expongo un caso de obstrucción tubárica postquirúrgica que fue resuelto mediante la aplicación de esta técnica innovadora y que tuvo un final feliz, el éxito buscado: embarazo, nacido vivo en óptimas condiciones, la felicidad materna y de su pareja. Con este reporte, además demuestro el beneficio post - quirúrgico cuando aplicamos menos material instrumental en la región operada y que es cuestión de adaptación de la técnica

    Ursodeoxycholic Acid Is Conjugated with Taurine to Promote Secretin-Stimulated Biliary Hydrocholeresis in the Normal Rat

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    BACKGROUND & AIMS: Secretin induces bicarbonate-rich hydrocholeresis in healthy individuals, but not in untreated patients with primary biliary cirrhosis (PBC). Ursodeoxycholic acid (UDCA)--the first choice treatment for PBC--restores the secretin response. Compared with humans, secretin has poor effect in experimental normal-rat models with biliary drainage, although it may elicit hydrocholeresis when the bile-acid pool is maintained. In view of the benefits of UDCA in PBC, we used normal-rat models to unravel the acute contribution of UDCA (and/or taurine-conjugated TUDCA) for eliciting the biliary secretin response. METHODS: Intravascular and/or intrabiliary administration of agonists and inhibitors was performed in normal rats with biliary monitoring. Secretin/bile-acid interplay was analyzed in 3D cultured rat cholangiocytes that formed expansive cystic structures with intralumenal hydroionic secretion. RESULTS: In vivo, secretin stimulates hydrocholeresis upon UDCA/TUDCA infusion, but does not modify the intrinsic hypercholeretic effect of dehydrocholic acid (DHCA). The former effect is dependent on microtubule polymerization, and involves PKCα, PI3K and MEK pathways, as shown by colchicine (i.p.) and retrograde biliary inhibitors. In vitro, while secretin alone accelerates the spontaneous expansion of 3D-cystic structures, this effect is enhanced in the presence of TUDCA, but not UDCA or DHCA. Experiments with inhibitors and Ca(2+)-chelator confirmed that the synergistic effect of secretin plus TUDCA involves microtubules, intracellular Ca(2+), PKCα, PI3K, PKA and MEK pathways. Gene silencing also demonstrated the involvement of the bicarbonate extruder Ae2. CONCLUSIONS: UDCA is conjugated in order to promote secretin-stimulated hydrocholeresis in rats through Ae2, microtubules, intracellular Ca(2+), PKCα, PI3K, PKA, and MEK

    Autoimmune neurological conditions associated with Zika virus infection

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    Zika virus (ZIKV) is an emerging flavivirus rapidly spreading throughout the tropical Americas. mosquitoes is the principal way of transmission of the virus to humans. ZIKV can be spread by transplacental, perinatal, and body fluids. ZIKV infection is often asymptomatic and those with symptoms present minor illness after 3 to 12 days of incubation, characterized by a mild and self-limiting disease with low-grade fever, conjunctivitis, widespread pruritic maculopapular rash, arthralgia and myalgia. ZIKV has been linked to a number of central and peripheral nervous system injuries such as Guillain-Barré syndrome (GBS), transverse myelitis (TM), meningoencephalitis, ophthalmological manifestations, and other neurological complications. Nevertheless, mechanisms of host-pathogen neuro-immune interactions remain incompletely elucidated. This review provides a critical discussion about the possible mechanisms underlying the development of autoimmune neurological conditions associated with Zika virus infection

    Field Evaluation of Smart Sensor Vehicle Detectors at Railroad Grade Crossings���Volume 4: Performance in Adverse Weather Conditions

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    The performance of a microwave radar system for vehicle detection at a railroad grade crossing with quadrant gates was evaluated in adverse weather conditions: rain (light and torrential), snow (light and heavy), dense fog, and wind. The first part of this report compares the results of the modified system setup in adverse weather conditions with those from good weather conditions (as presented in Volume 3 of this study). Then, the results of a re-modified system setup were compared to the results for the modified system setup in good and adverse weather conditions. The re-modification was in response to increased detection errors in adverse weather conditions. With the modified setup, system performance was sensitive to the adverse weather conditions. In torrential rain, false calls increased to 24.82%–27.08% (e.g., May 28 and June 1) when there was some traffic on the crossing. However, when there was torrential rain but only one vehicle (e.g., May 31) or no traffic flow (e.g., June 10), the radar units generated 15 false calls on each of those 2 days. For all heavy snow datasets combined, missed calls by a single radar unit and by the two radar units working as a combined unit (i.e., systemwide) represented 13.51% and 11.66% of the loop calls, respectively. The most severe snow effects were found during freezing rain/ice. In dense fog, false calls increased to 11.58%, and all false calls were generated when the gates were moving or in the down position. Wind did not affect system performance, and the errors were similar to those in good weather conditions. With the re-modified setup, the frequency of errors in heavy rain and heavy snow conditions was reduced and system performance was similar to the good weather, light rain, and light snow conditions. In heavy rain, false calls in the re-modified setup were reduced to 2.6% compared with 30.5% in the modified setup. This reduction was the result of a significant decrease in the false calls generated without objects in the crossing. The re-modified setup eliminated the systemwide missed calls in heavy snow. The re-modified setup also reduced the false calls to less than 1% in good weather, light rain, and light snow conditions and practically had no missed, stuck-on, or dropped calls. Results indicate that re-modifications improved the performance of detection system.Illinois Department of Transportation, R27-095Ope

    Localized waves in silicates. What do we know from experiments?

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    Since the latest review about solitary localized waves in muscovite, called quodons, (F.M. Russell in Quodons in Mica. Springer, Cham, pp. 475–559, 2015a [1], F.M. Russell in Quodons in Mica. Springer, Cham, pp. 3–33, 2015b [2]) there have been many developments, specially from the point of view of experiments, published in several journals. The breakthrough hypothesis that was advanced in that review that dark tracks were produced by positive electrical charge moving in a localized wave, either transported by swift particles or by nonlinear localized waves, has been confirmed by experiments in muscovite and other silicates. In this paper we review the experimental results, some already published and some new, specially the phenomenon of charge transport without an electric field, called hyperconductivity. We also consider alternative explanations as phase transitions for other tracks. We also attempt to describe numerical simulations that have confirmed the order of magnitude of quodons energy and calculations underway to determine more properties of electron and hole transport by quodons.Ministerio de Ciencia e Innovación MICINN PID2019-109175GB-C22Junta de Andalucía PAIDI 2019/FQM-280Universidad de Sevilla VIPPITUS 2020Universiad de Sevilla VIPPITUS 201

    Proof-of-Concept Application - Annual Report Year 2

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    This document first gives an introduction to Application Layer Networks and subsequently presents the catallactic resource allocation model and its integration into the middleware architecture of the developed prototype. Furthermore use cases for employed service models in such scenarios are presented as general application scenarios as well as two very detailed cases: Query services and Data Mining services. This work concludes by describing the middleware implementation and evaluation as well as future work in this area. --Grid Computing

    Joint Ultra-wideband Characterization of Azimuth, Elevation and Time of Arrival with Toric Arrays

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    In this paper, we present an analytical framework for the joint characterization of the 3D direction of arrival (DoA), i.e., azimuth and elevation components, and time of arrival (ToA) in multipath environments. The analytical framework is based on the use of nearly frequency-invariant beamformers (FIB) formed by toric arrays. The frequency response of the toric array is expanded as a series of phase modes, which leads to azimuth-time and elevation-time diagrams from which the 3D DoA and the ToA of the incoming waves can be extracted over a wide bandwidth. Firstly, we discuss some practical considerations, advantages and limitations of using the analytical method. Subsequently, we perform a parametric study to analyze the influence of the method parameters on the quality of the estimation. The method is tested in single-path and multipath mm-wave environments over a large bandwidth. The results show that the proposed method improves the quality of the estimation, i.e., decreases the level of the artifacts, compared to other state-of-art FIB approaches based on the use of single/concentric circular and elliptical arrays.Comment: 10 pages, 8 figure
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