10 research outputs found

    Waveguide antenna array for automotive radar

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    Automotive radars can use the wide band at extremely high frequencies (EHF) between 30 GHz and 300 GHz, which has a higher amount of free frequency bands than the lower part of the electromagnetic spectrum. The focus of this thesis is to develop a horn antenna to work in this band with the central frequency of 77 GHz, a Field of View (FOV) of 20º on Elevation and 130º on Azimuth and a reflection coefficient (S11) below -15 dB. It was possible to accomplish the requirements set by the company with a single horn antenna, which is a less complex and more compact solution. This thesis presents the results with a brief review of a two-element antenna array for possible future works.Los radares de automoción pueden utilizar la banda ancha a frecuencias extremadamente altas (EHF) entre 30 GHz y 300 GHz, que tiene una mayor cantidad de bandas de frecuencia libres que la parte inferior del espectro electromagnético. El objetivo de esta tesis es desarrollar una antena de bocina para trabajar en esta banda con la frecuencia central de 77 GHz, un campo de visión de 20º en elevación y 130º en azimut y un coeficiente de reflexión (S11) por debajo de los - 15 dB. Fue posible cumplir los requisitos establecidos por la empresa con una sola antena de bocina, que es una solución menos compleja y más compacta. Esta tesis presenta los resultados con una breve revisión de una matriz de antenas de dos elementos para posibles trabajos futuros.Els radars d'automoció poden utilitzar la banda ampla a freqüències extremadament altes (EHF) entre 30 GHz i 300 GHz, que té una major quantitat de bandes de freqüència lliures que la part inferior de l'espectre electromagnètic. L'objectiu d'aquesta tesi és desenvolupar una antena de botzina per treballar en aquesta banda amb la freqüència central de 77 GHz, un camp de visió de 20º en elevació i 130º en azimut i un coeficient de reflexió (S11) per sota dels -15 dB. Va ser possible complir els requisits establerts per l'empresa amb una sola antena de botzina, que és una solució menys complexa i més compacta. Aquesta tesi presenta els resultats amb una breu revisió d'una matriu d'antenes de dos elements per a possibles treballs futurs

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites

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    The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples.Peer reviewe

    Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign

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    Abstract: In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M ⊙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87’s spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded

    Monitoratge amb microones de stents biodegradables.

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    The main purpose of this project is to provide a simple, economical and useful device that enables the study of the effects of changes of biodegradable vascular stents in a well-controlled environment.El objetivo principal de este proyecto es crear un dispositivo simple y económico que permita el estudio de los efectos del paso del tiempo sobre stents biodegradables en un ambiente controlado.L'objectiu principal d'aquest projecte és crear un dispositiu simple i econòmic que permeti l'estudi dels efectes del pas del temps sobre stents biodegradables en un ambient controlat

    Clinical validation of cutoff target ranges in newborn screening of metabolic disorders by tandem mass spectrometry: A worldwide collaborative project

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    PURPOSE:: To achieve clinical validation of cutoff values for newborn screening by tandem mass spectrometry through a worldwide collaborative effort. METHODS:: Cumulative percentiles of amino acids and acylcarnitines in dried blood spots of approximately 25-30 million normal newborns and 10,742 deidentified true positive cases are compared to assign clinical significance, which is achieved when the median of a disorder range is, and usually markedly outside, either the 99th or the 1st percentile of the normal population. The cutoff target ranges of analytes and ratios are then defined as the interval between selected percentiles of the two populations. When overlaps occur, adjustments are made to maximize sensitivity and specificity taking all available factors into consideration. RESULTS:: As of December 1, 2010, 130 sites in 45 countries have uploaded a total of 25,114 percentile data points, 565,232 analyte results of true positive cases with 64 conditions, and 5,341 cutoff values. The average rate of submission of true positive cases between December 1, 2008, and December 1, 2010, was 5.1 cases/day. This cumulative evidence generated 91 high and 23 low cutoff target ranges. The overall proportion of cutoff values within the respective target range was 42% (2,269/5,341). CONCLUSION:: An unprecedented level of cooperation and collaboration has allowed the objective definition of cutoff target ranges for 114 markers to be applied to newborn screening of rare metabolic disorders. © 2011 Lippincott Williams &amp; Wilkins

    The Effects of Cinacalcet in Older and Younger Patients on Hemodialysis: The Evaluation of Cinacalcet HCl Therapy to Lower Cardiovascular Events (EVOLVE) Trial.

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    This article contains supplemental material online at http://cjasn. asnjournals.org/lookup/suppl/doi:10.2215/CJN.07730814/-/ DCSupplemental.BACKGROUND AND OBJECTIVES: The calcimimetic cinacalcet reduced the risk of death or cardiovascular (CV) events in older, but not younger, patients with moderate to severe secondary hyperparathyroidism (HPT) who were receiving hemodialysis. To determine whether the lower risk in younger patients might be due to lower baseline CV risk and more frequent use of cointerventions that reduce parathyroid hormone (kidney transplantation, parathyroidectomy, and commercial cinacalcet use), this study examined the effects of cinacalcet in older (≥65 years, n=1005) and younger (3-fold higher in younger relative to older patients and were more frequent in patients randomized to placebo. In older patients, the adjusted relative hazard (95% confidence interval) for the primary composite (CV) end point (cinacalcet versus placebo) was 0.70 (0.60 to 0.81); in younger patients, the relative hazard was 0.97 (0.86 to 1.09). Corresponding adjusted relative hazards for mortality were 0.68 (0.51 to 0.81) and 0.99 (0.86 to 1.13). Reduction in the risk of severe unremitting HPT was similar in both groups. CONCLUSIONS: In the EVOLVE trial, cinacalcet decreased the risk of death and of major CV events in older, but not younger, patients with moderate to severe HPT who were receiving hemodialysis. Effect modification by age may be partly explained by differences in underlying CV risk and differential application of cointerventions that reduce parathyroid hormone.The Evaluation of Cinacalcet HCl Therapy to Lower Cardiovascular Events (EVOLVE) trial was funded by Amgen

    ПОЯСНЮВАЛЬНА ЗАПИСКА кваліфікаційної роботи бакалавра студента Варганова_Дмитра_Дмитровича напряму підготовки 124 Системний аналіз

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    Об’єкт дослідження – підприємство КПШНЗ «СДЮСШОР з кінного спорту» ДМР. Предмет дослідження – приготування кормів для годування тренованих і спортивних коней. Мета дослідження: оптимізація витрат підприємства шляхом удосконалення технологій виробництва і рецептів кормів для тренованих і спортивних коней, підвищення їх якості та зниження питомих витрат на виробництво. Методи дослідження: методи багатокритеріальної та нечіткої оптимізації Економічна ефективність: очікується позитивною завдяки розробці оптимальних кормових сумішей, які дозволяють отримувати більше користі для коней та знизити витрати на компоненти, це дозволяє збільшити прибуток підприємства.Кваліфікаційна робота ступеня бакалавр напряму підготовки 124 Системний аналіз, НТУ "Дніпровська політехніка", м. Дніпро, 2020 р. Практична цінність роботи полягає у розробці математичних моделей, які дозволяють визначити оптимальну суміш корму, котра буде відповідати необхідним умовам

    Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A

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    Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign

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