1,634 research outputs found
Capacidad ergódica de sistemas MIMO basados en antenas con polarización dual
MIMO systems based on dual-polarized antennas
at transmitter and receiver constitute an interesting alternative
to conventional MIMO configurations. This paper analyzes the
ergodic capacity of such systems in urban micro- and picocellular
environments. The MIMO channel is modeled by using
a site-specific ray-tracing propagation tool. This technique
permits to analyze the impact of environmental parameters, like
antennas location and orientation, on the system performance.
Ergodic capacity estimations in a specific urban environment are
presented
Report of the Scientific Committee of the Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) on the conditions of use of certain substances to be used in food supplements-4
Los complementos alimenticios son alimentos cuyo fin es complementar la dieta normal y que consisten en fuentes concentradas de nutrientes (vitaminas y minerales) o de otras sustancias que tienen un efecto nutricional o fisiológico, en forma simple o combinada. Los complementos se comercializan en forma dosificada, se entregan al consumidor final únicamente preenvasados. En ningún caso, deben sustituir al uso de medicamentos sin una supervisión médica adecuada. Sólo deben utilizarse para complementar la dieta y, de forma general, su uso no es necesario si se sigue una dieta variada y equilibrada, a la que no pueden reemplazar.
En España los complementos alimenticios están regulados por el Real Decreto 1487/2009 que traspuso a la legislación española la Directiva 2002/46/CE relativa a la aproximación de las legislaciones de los estados miembros en materia de complementos alimenticios. Sin embargo, actualmente sólo está regulado el uso de vitaminas y minerales, por lo que se ha solicitado al Comité Científico que realice una valoración de la propuesta de autorización de la utilización de determinadas sustancias distintas de vitaminas y minerales en la fabricación de complementos alimenticios. Las sustancias propuestas por la Agencia Española de Consumo, Seguridad Alimentaria y Nutrición (AECOSAN) son: ácido L-aspártico, L-citrulina, glicina, L-prolina, L-serina, L-arginina-L-aspartato, L-lisina-L-aspartato, L-lisina-L-glutamato, N-acetil-L-cisteína, N-acetil-L-metionina, hidroximetilbu-
tirato, ácido lipoico, Monascus purpureus, carbón activo y lactulosa.
El Comité Científico ha valorado cada propuesta, analizando las características y fuentes de cada sustancia, así como la nutrición, metabolismo y seguridad y ha concluido, en cada caso, si la presentada por la AECOSAN era aceptable desde el punto de vista de su seguridad en su uso como complemento alimenticio. En ningún caso, la evaluación realizada supone un aval de la eficacia biológica de las sustancias y dosis valoradas. El Comité Científico indica que, en todo caso es necesario que las personas que estén sometidas a tratamientos con medicamentos consulten con su médico la oportunidad o conveniencia de consumir complementos alimenticios dada la posibilidad de que existan interferencias en algunos casos.Food supplements are foods, the purpose of which is to supplement the normal diet and which consist of concentrated nutrient sources (vitamins and minerals) or other substances with a nutritional or physiological effect, alone or in combination. The supplements are marketed in dosage form and are only supplied to the end consumer prepacked. In no event should they replace the use of medicines without suitable medical supervision. They should only be used to supplement the diet and, on the whole, their usage is not required if the individual has a varied and balanced diet, which cannot be replaced.
In Spain, food supplements are regulated by Royal Decree 1487/2009, which transposed Directive 2002/46/EC on the approximation of the laws of the Member States relating to food supplements into Spanish law. However, only the use of vitamins and minerals is currently regulated. Therefore the Scientific Committee has been asked to make an assessment of the proposal to authorise certain substances other than vitamins and minerals in the manufacture of food supplements. The substances proposed by the Spanish Agency for Consumer Affairs, Food Safety and Nutrition (AECOSAN) are food supplements, L-aspartic acid, L-citrulline, glycine, L-proline, L-serine, L-arginine-L-aspar-
tate, L-lysine L-aspartate, L-lysine-L-glutamate, N-acetyl-L-cysteine, N-acetyl-L-methionine, hidro-
xymethylbutyrate, lipoic acid, Monascus purpureus, activated carbon and lactulose.
The Scientific Committee has assessed each proposal, analysing the characteristics and sources of each substance, and the nutrition, metabolism and safety and has concluded, in each case, whether that submitted by the AECOSAN is acceptable from a safety viewpoint for use as a food supplement. In no event is the assessment intended as a guarantee of the biological efficiency of the substances and doses assessed. The Scientific Committee states that, in any case individuals undergoing medical treatment must seek medical advice as to the suitability of taking food supplements, given the possibility of interactions in certain cases
Are Farm-Reared Quails for Game Restocking Really Common Quails (Coturnix coturnix)?: A Genetic Approach
The common quail (Coturnix coturnix) is a popular game species for which restocking with farm-reared individuals is a common practice. In some areas, the number of released quails greatly surpasses the number of wild breeding common quail. However, common quail are difficult to raise in captivity and this casts suspicion about a possible hybrid origin of the farmed individuals from crosses with domestic Japanese quail (C. japonica). In this study we used a panel of autosomal microsatellite markers to characterize the genetic origin of quails reared for hunting purposes in game farms in Spain and of quails from an experimental game farm which was founded with hybrids that have been systematically backcrossed with wild common quails. The genotypes of these quail were compared to those of wild common quail and domestic strains of Japanese quail. Our results show that more than 85% of the game farm birds were not common quail but had domestic Japanese quail ancestry. In the experimental farm a larger proportion of individuals could not be clearly separated from pure common quails. We conclude that the majority of quail sold for restocking purposes were not common quail. Genetic monitoring of individuals raised for restocking is indispensable as the massive release of farm-reared hybrids could represent a severe threat for the long term survival of the native species
Hyperkalemia in Heart Failure Patients in Spain and Its Impact on Guidelines and Recommendations: ESC-EORP-HFA Heart Failure Long-Term Registry
[Abstract] Introduction and objectives: Hyperkalemia is a growing concern in the treatment of patients with heart failure and reduced ejection fraction because it limits the use of effective drugs. We report estimates of the magnitude of this problem in routine clinical practice in Spain, as well as changes in potassium levels during follow-up and associated factors.
Methods: This study included patients with acute (n=881) or chronic (n=3587) heart failure recruited in 28 Spanish hospitals of the European heart failure registry of the European Society of Cardiology and followed up for 1 year. Various outcomes were analyzed, including changes in serum potassium levels and their impact on treatment.
Results: Hyperkalemia (K+> 5.4 mEq/L) was identified in 4.3% (95%CI, 3.7%-5.0%) and 8.2% (6.5%-10.2%) of patients with chronic and acute heart failure, respectively, and was responsible for 28.9% of all cases of contraindication to mineralocorticoid receptor antagonist use and for 10.8% of all cases of failure to reach the target dose. Serum potassium levels were not recorded in 291 (10.8%) of the 2693 chronic heart failure patients with reduced ejection fraction. During follow-up, potassium levels increased in 179 of 1431 patients (12.5%, 95%CI, 10.8%-14.3%). This increase was directly related to age, diabetes, and history of stroke and was inversely related to history of hyperkalemia.
Conclusions: This study highlights the magnitude of the problem of hyperkalemia in patients with heart failure in everyday clinical practice and the need to improve monitoring of this factor in these patients due to its interference with the possibility of receiving optimal treatment.[Resumen] Introducción y objetivos. La hiperpotasemia es una preocupación creciente en el tratamiento de los pacientes con insuficiencia cardiaca y fracción de eyección reducida, pues limita el uso de fármacos eficaces. Este trabajo ofrece estimaciones de la magnitud de este problema en la práctica clínica habitual en España, los cambios en las concentraciones de potasio en el seguimiento y los factores asociados.
Métodos. Pacientes con insuficiencia cardiaca aguda (n = 881) y crónica (n = 3.587) seleccionados en 28 hospitales españoles del registro europeo de insuficiencia cardiaca de la European Society of Cardiology y seguidos 1 año para diferentes desenlaces, incluidos cambios en las cifras de potasio y su impacto en el tratamiento.
Resultados. La hiperpotasemia (K+ > 5,4 mEq/l) está presente en el 4,3% (IC95%, 3,7-5,0%) y el 8,2% (6,5-10,2%) de los pacientes con insuficiencia cardiaca crónica y aguda; causa el 28,9% de todos los casos en que se contraindica el uso de antagonistas del receptor de mineralocorticoides y el 10,8% de los que no alcanzan la dosis objetivo. Del total de 2.693 pacientes ambulatorios con fracción de eyección reducida, 291 (10,8%) no tenían registrada medición de potasio. Durante el seguimiento, 179 de 1.431 (12,5%, IC95%, 10,8-14,3%) aumentaron su concentración de potasio, aumento relacionado directamente con la edad, la diabetes mellitus y los antecedentes de ictus e inversamente con los antecedentes de hiperpotasemia.
Conclusiones. Este trabajo destaca el problema de la hiperpotasemia en pacientes con insuficiencia cardiaca de la práctica clínica habitual y la necesidad de continuar y mejorar la vigilancia de este factor en estos pacientes por su interferencia en el tratamiento óptimo
Effect of viral storm in patients admitted to intensive care units with severe COVID-19 in Spain: a multicentre, prospective, cohort study
Background: The contribution of the virus to the pathogenesis of severe COVID-19 is still unclear. We aimed to evaluate associations between viral RNA load in plasma and host response, complications, and deaths in critically ill patients with COVID-19. Methods: We did a prospective cohort study across 23 hospitals in Spain. We included patients aged 18 years or older with laboratory-confirmed SARS-CoV-2 infection who were admitted to an intensive care unit between March 16, 2020, and Feb 27, 2021. RNA of the SARS-CoV-2 nucleocapsid region 1 (N1) was quantified in plasma samples collected from patients in the first 48 h following admission, using digital PCR. Patients were grouped on the basis of N1 quantity: VIR-N1-Zero ([removed]2747 N1 copies per mL). The primary outcome was all-cause death within 90 days after admission. We evaluated odds ratios (ORs) for the primary outcome between groups using a logistic regression analysis. Findings: 1068 patients met the inclusion criteria, of whom 117 had insufficient plasma samples and 115 had key information missing. 836 patients were included in the analysis, of whom 403 (48%) were in the VIR-N1-Low group, 283 (34%) were in the VIR-N1-Storm group, and 150 (18%) were in the VIR-N1-Zero group. Overall, patients in the VIR-N1-Storm group had the most severe disease: 266 (94%) of 283 patients received invasive mechanical ventilation (IMV), 116 (41%) developed acute kidney injury, 180 (65%) had secondary infections, and 148 (52%) died within 90 days. Patients in the VIR-N1-Zero group had the least severe disease: 81 (54%) of 150 received IMV, 34 (23%) developed acute kidney injury, 47 (32%) had secondary infections, and 26 (17%) died within 90 days (OR for death 0·30, 95% CI 0·16–0·55; p<0·0001, compared with the VIR-N1-Storm group). 106 (26%) of 403 patients in the VIR-N1-Low group died within 90 days (OR for death 0·39, 95% CI 0·26–0·57; p[removed]11 página
International Consensus Document on Obstructive Sleep Apnea
El objetivo principal de este documento internacional de consenso sobre apnea obstructiva del sueno es proporcionar unas directrices que permitan a los profesionales sanitarios tomar las mejores decisiones en la asistencia de los pacientes adultos con esta enfermedad según un resumen crítico de la literatura más actualizada. El grupo de trabajo de expertos se ha constituido principalmente por 17 sociedades científicas y 56 especialistas con amplia representación geográfica (con la participación de 4 sociedades internacionales), además de un metodólogo experto y un documentalista del Centro Cochrane Iberoamer icano. El documento consta de un manuscrito principal, con las novedades más relevantes del DIC, y una serie de manuscritos online que recogen las búsquedas bibliográficas sistemáticas de cada uno de los apartados del DIC. Este documento no cubre la edad pediátrica ni el manejo del paciente en ventilación mecánica crónica no invasiva (que se publicarán en sendos documentos de consenso aparte)
Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV
The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8 TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
Role of age and comorbidities in mortality of patients with infective endocarditis
[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality.
[Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk.
[Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality.
[Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group
- …