3,253 research outputs found

    Isocausal spacetimes may have different causal boundaries

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    We construct an example which shows that two isocausal spacetimes, in the sense introduced by Garc\'ia-Parrado and Senovilla, may have c-boundaries which are not equal (more precisely, not equivalent, as no bijection between the completions can preserve all the binary relations induced by causality). This example also suggests that isocausality can be useful for the understanding and computation of the c-boundary.Comment: Minor modifications, including the title, which matches now with the published version. 12 pages, 3 figure

    Effect of Acipimox on Plasma Lipids and Glucose/Insulin in Pregnant Rats

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    To determine how a reduction in maternal hypertriglyceridemia during late pregnancy may affect glucose/insulin relationships, pregnant and virgin rats were orally treated with acipimox, a potent antilipolytic agent. In 20-day pregnant rats receiving 80 mg of acipimox, plasma triglycerides (TG), free fatty acids (FFA), and glycerol decreased more than in virgin rats shortly after the drug (up to 7 hours), when compared with animals treated with distilled water, whereas plasma glucose level was unaffected by the treatment in either group of rats. When acipimox was given every 12 hours from day 17 to day 20 of pregnancy, plasma TG, FFA, and glycerol levels progressively increased, whereas they either decreased or did not change in virgin rats receiving the same treatment, with no effect in plasma glucose levels in either group. Fetal body weight was lower than in controls in 20-day pregnant rats that received acipimox for 3 days. On day 20 of pregnancy, 3 hours after receiving acipimox or distilled water, rats received a 2 g glucose/kg oral load and it was found that the change in plasma glucose was similar in both groups, whereas the increase in plasma insulin was greater in pregnant rats treated with acipimox. However, no difference was found in either variable after the oral glucose load in virgin rats receiving acipimox or distilled water. No differences in plasma glucose levels were found after intravenous (IV) administration of insulin in pregnant rats treated or not treated with acipimox. In conclusion, present results show that administration of acipimox during the last days of gestation inhibited lipolysis and decreased fetal weight. Over a short period of time, in pregnant rats, reductions of plasma FFA and TG after acipimox treatment improved the glucose-induced insulin release, but did not seem to have any effect in peripheral insulin resistance

    Effectiveness of a telerehabilitation intervention using ReCOVery APP of long COVID patients: a randomized, 3-month follow-up clinical trial

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    The main objective of this study is to analyze the clinical efficacy of telerehabilitation in the recovery of Long COVID patients through ReCOVery APP for 3 months, administered in the Primary Health Care context. The second objective is to identify significant models associated with an improvement in the study variables. An open-label randomized clinical trial was conducted using two parallel groups of a total of 100 Long COVID patients. The first group follows the treatment as usual methods established by their general practitioner (control group) and the second follows the same methods and also uses ReCOVery APP (intervention group). After the intervention, no significant differences were found in favour of the group intervention. Regarding adherence, 25% of the participants made significant use of the APP. Linear regression model establishes that the time of use of ReCOVery APP predicts an improvement in physical function (b = 0.001; p = 0.005) and community social support (b = 0.004; p = 0.021). In addition, an increase in self-efficacy and health literacy also contribute to improving cognitive function (b = 0.346; p = 0.001) and reducing the number of symptoms (b = 0.226; p = 0.002), respectively. In conclusion, the significant use of ReCOVery APP can contribute to the recovery of Long COVID patients. Trial Registration No.: ISRCTN91104012

    Computability of the causal boundary by using isocausality

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    Recently, a new viewpoint on the classical c-boundary in Mathematical Relativity has been developed, the relations of this boundary with the conformal one and other classical boundaries have been analyzed, and its computation in some classes of spacetimes, as the standard stationary ones, has been carried out. In the present paper, we consider the notion of isocausality given by Garc\'ia-Parrado and Senovilla, and introduce a framework to carry out isocausal comparisons with standard stationary spacetimes. As a consequence, the qualitative behavior of the c-boundary (at the three levels: point set, chronology and topology) of a wide class of spacetimes, is obtained.Comment: 44 pages, 5 Figures, latex. Version with minor changes and the inclusion of Figure

    Stain-free detection as loading control alternative to Ponceau and housekeeping protein immunodetection in Western blotting

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    The authors want to thank the input of Arnaud Remy and Enrique Orozco of Bio-Rad Laboratories. This study was supported by the Ministry of Science and Innovation (SAF2011-22922 and SAF2011-22812), and by funds from Junta de Andalucia (CTS6736 and CTS164). B. Rivero and A. Anzola were supported by fellowships of the Ministry of Education and Science of Spain and Junta de Andalucia, respectively. CIBERehd is funded by the Instituto de Salud Carlos III.It is currently a routine practice to require a measurement of a housekeeping reference, including actin, glyceraldehyde-3-phosphate dehydrogenase, β-tubulin, among others, in Western blots, as it is the rule in RNA blots. Reversible Ponceau staining has been applied successfully to check equal loading of gels. Here we test a new technique, with the Stain-Free gels from Bio-Rad, against both Ponceau staining and housekeeping protein immunodetection under different conditions. Our results show that Stain-Free gels outperform Ponceau staining and that both are more consistent than housekeeping proteins as a loading control.Spanish Government SAF2011-22922 SAF2011-22812Junta de Andalucia CTS6736 CTS164Instituto de Salud Carlos II

    The QUEST RR Lyrae Survey: Confirmation of the Clump at 50 kpc and Other Over-Densities in the Outer Halo

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    We have measured the periods and light curves of 148 RR Lyrae variables from V=13.5 to 19.7 from the first 100 sq. degrees of the QUEST RR Lyrae survey. Approximately 55% of these stars belong to the clump of stars detected earlier by the Sloan Digital Sky Survey. According to our measurements, this feature has ~10 times the background density of halo stars, spans at least 37.5 deg by 3.5 deg in right ascension and declination (>=30 by >=3 kpc), lies ~50 kpc from the Sun, and has a depth along the line of sight of ~5 kpc (1 sigma). These properties are consistent with the recent models that suggest it is a tidal stream from the Sgr dSph galaxy. The mean period of the type ab variables, 0.58 d, is also consistent. In addition, we have found two smaller over-densities in the halo, one of which may be related to the globular cluster Pal 5.Comment: 12 pages (including 4 figures). Accepted for publication in the ApJ Letter

    Síndrome de Lady Windermere como causa de tos crónica. A propósito de un caso

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    Nontuberculous mycobacteria are rarely recognized in the world today; their prevalence is increasing due to suspicion in immunocompromised patients or in those suffering from chronic illnesses such as cystic fibrosis. A case with of Lady Windermere Syndrome diagnosis that originally started with chronic cough is presented. Tomography showed bilateral bronchiectasis in the left lingual segment and in the middle and lower right lobe. Mycobacterium avium-intracellulare complex was isolated using bronchoscopy. The lack of suspicion of nontuberculous mycobacteria in patients without risk factors and chronic cough leads to diagnosis delay and clinical deterioration of the patient.Las micobacterias no tuberculosas son poco reconocidas hoy en el mundo, incrementándose su prevalencia a punto de partida de su sospecha en inmunodeprimidos o en enfermedades crónicas, como la fibrosis quística. Se presenta el caso de una paciente con diagnóstico de síndrome de Lady Windermere a punto de partida de un cuadro de tos crónica. Se realizó tomografía computarizada donde se evidenciaron bronquiectasias en el segmento lingular del pulmón izquierdo y en los lóbulos medio e inferior del derecho. Mediante la broncoscopia se aisló el complejo Mycobacterium avium-intracellulare. La falta de sospecha de micobacterias atípicas en pacientes sin factores predisponentes, con un cuadro de tos crónica, conduce al retraso en el diagnóstico y el deterioro clínico del paciente

    Discovery of the Optical Transient of the Gamma Ray Burst 990308

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    The optical transient of the faint Gamma Ray Burst 990308 was detected by the QUEST camera on the Venezuelan 1-m Schmidt telescope starting 3.28 hours after the burst. Our photometry gives V=18.32±0.07V = 18.32 \pm 0.07, R=18.14±0.06R = 18.14 \pm 0.06, B=18.65±0.23B = 18.65 \pm 0.23, and R=18.22±0.05R = 18.22 \pm 0.05 for times ranging from 3.28 to 3.47 hours after the burst. The colors correspond to a spectral slope of close to fνν1/3f_{\nu} \propto \nu^{1/3}. Within the standard synchrotron fireball model, this requires that the external medium be less dense than 104cm310^{4} cm^{-3}, the electrons contain >20> 20% of the shock energy, and the magnetic field energy must be less than 24% of the energy in the electrons for normal interstellar or circumstellar densities. We also report upper limits of V>12.0V > 12.0 at 132 s (with LOTIS), V>13.4V > 13.4 from 132-1029s (with LOTIS), V>15.3V > 15.3 at 28.2 min (with Super-LOTIS), and a 8.5 GHz flux of <114μJy< 114 \mu Jy at 110 days (with the Very Large Array). WIYN 3.5-m and Keck 10-m telescopes reveal this location to be empty of any host galaxy to R>25.7R > 25.7 and K>23.3K > 23.3. The lack of a host galaxy likely implies that it is either substantially subluminous or more distant than a red shift of 1.2\sim 1.2.Comment: ApJ Lett submitted, 5 pages, 2 figures, no space for 12 coauthor

    Comportamiento de variables predictivas de exacerbaciones de la EPOC en el Hospital Neumológico de Cuba

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    La utilización de variables predictoras de exacerbaciones de la EPOCno es una práctica generalizada en nuestro medio, por lo que no podemos caracterizar los pacientes exacerbadores ni diseñar estrategias para su manejo integral. Se realizó un estudio descriptivo prospectivo correlacionar en pacientes con diagnóstico de EPOC del Hospital Neumológico de Cuba, con el objetivo de determinar la asociación entre variables clínicas, funcionales e imagenológicas y la frecuencia de exacerbaciones al año. La población estuvo constituida por pacientes con diagnóstico clínico de EPOC y la muestra por aquellos pacientes con diagnóstico confirmado que cumplieran los criterios de inclusión. La correlación entre las variables se realizó mediante el Coeficiente de Correlación de Pearson con un intervalo de Confianza del 95% y la prueba t de student con un nivel de significación (p) menor de 0.05.El 81.82% de los pacientes muy graves son agudizadores con enfisema. El 75% de los pacientes con índice de la arteria pulmonar/ aorta tienen más de dos exacerbaciones al año. El 84.61% de los pacientes agudizadores presentaron grado cuatro de la disnea. La presión media de la arteria pulmonar junto al VEF1 constituyeron los mejores predictores de exacerbaciones en el grupo de pacientes estudiados.</p
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