94 research outputs found
Using galaxy pairs as cosmological tracers
The Alcock-Paczynski (AP) effect uses the fact that, when analyzed with the
correct geometry, we should observe structure that is statistically isotropic
in the Universe. For structure undergoing cosmological expansion with the
background, this constrains the product of the Hubble parameter and the angular
diameter distance. However, the expansion of the Universe is inhomogeneous and
local curvature depends on density. We argue that this distorts the AP effect
on small scales. After analyzing the dynamics of galaxy pairs in the Millennium
simulation, we find an interplay between peculiar velocities, galaxy properties
and local density that affects how pairs trace cosmological expansion. We find
that only low mass, isolated galaxy pairs trace the average expansion with a
minimum "correction" for peculiar velocities. Other pairs require larger, more
cosmology and redshift dependent peculiar velocity corrections and, in the
small-separation limit of being bound in a collapsed system, do not carry
cosmological information.Comment: 15 pages, 14 figures, 1 tabl
Biology teachers’ conceptions of Humankind Origin across secular and religious countries: an international comparison
Striving toward a better understanding of how the global spread of creationist ideology may impact biology teachers and teaching worldwide, this study comparatively examines how biology teachers from three Latin American countries (Argentina, Brazil, and Uruguay) conceive the origin of humankind. It is reported that teachers from Uruguay (the most secular country) and Argentina (a country with intermediate religiosity) more frequently associated humankind origin with scientific terms Evolution, Natural selection, and Australopithecus. In contrast, Brazilian teachers stood out as those most frequently associating humankind’s origin to the religious term “God” alongside scientific terms. This study underscores the importance of the interplay of social factors (societal religiosity) and psychological factors (e.g., personal commitment) when considering the impact of teacher exposure to creationist ideology. It also highlights the need for biology teachers (particularly those in more religious countries) to undergo professional development.Portuguese national funds through the FCT (Foundation for Science and Technology) within the framework of the CIEC (Research Center for Child Studies of the University of Minho) project under the reference UIDB/00317/202
Artificial Pancreas: First Clinical Trials in Argentina
The first clinical trials using an Artificial Pancreas (AP) in Latin America have been defined in 2 stages. The first stage was carried out in November 2016 with the UVA controller (developed by the Center for Diabetes Technology and already clinically tested), and the second will be performed during the first semester of 2017 with the ARG (Automatic Regulation of Glucose) algorithm (developed by ITBA, UNQ, and UNLP in Argentina). Both tests are based on the DiAs (Diabetes Assistant) from the UVA, and are performed in the HIBA on 5 patients with Type 1 Diabetes Mellitus (T1DM), for 36 hours. For the first stage, Open-Loop (OL) insulin boluses were applied before meals and patient’s physical activity was included. On the other hand, for the second stage, patients will not be involved in physical activity, but no OL insulin boluses will be injected before meals. In this work, experimental results from the first stage with the UVA controller, and preliminary results with the ARG control algorithm tested on the UVA/Padova simulator are presented. Due to the final paper deadline, the experimental results from the second stage are not included here, but will be presented at the IFAC World Congress.Facultad de IngenieríaInstituto de Investigaciones en Electrónica, Control y Procesamiento de Señale
A Randomized Trial of Convalescent Plasma in Covid-19 Severe Pneumonia
BACKGROUND:Convalescent plasma is frequently administered to patients with Covid-19 and hasbeen reported, largely on the basis of observational data, to improve clinical outcomes.Minimal data are available from adequately powered randomized, controlled trials.
METHODS:We randomly assigned hospitalized adult patients with severe Covid-19 pneumoniain a 2:1 ratio to receive convalescent plasma or placebo. The primary outcome wasthe patient?s clinical status 30 days after the intervention, as measured on a six-pointordinal scale ranging from total recovery to death.
RESULTS:A total of 228 patients were assigned to receive convalescent plasma and 105 toreceive placebo. The median time from the onset of symptoms to enrollment inthe trial was 8 days (interquartile range, 5 to 10), and hypoxemia was the mostfrequent severity criterion for enrollment. The infused convalescent plasma had amedian titer of 1:3200 of total SARS-CoV-2 antibodies (interquartile range, 1:800 to1:3200]. No patients were lost to follow-up. At day 30 day, no significant differencewas noted between the convalescent plasma group and the placebo group in thedistribution of clinical outcomes according to the ordinal scale (odds ratio, 0.83(95% confidence interval [CI], 0.52 to 1.35; P=0.46). Overall mortality was 10.96%in the convalescent plasma group and 11.43% in the placebo group, for a risk difference of −0.46 percentage points (95% CI, −7.8 to 6.8). Total SARS-CoV-2 antibodytiters tended to be higher in the convalescent plasma group at day 2 after the intervention. Adverse events and serious adverse events were similar in the two groups.
CONCLUSIONS:no significant differences were observed in clinical status or overall mortality between patients treated with convalescent plasma and those who received placebo.(PlasmAr ClinicalTrials.gov number, NCT04383535.)Fil: Simonovich, Ventura A.. Hospital Italiano. Departamento de Medicina. Servicio de Clinica Medica.; ArgentinaFil: Burgos Pratx, Leandro D.. Hospital Italiano. Departamento de Medicina. Servicio de Clinica Medica.; ArgentinaFil: Scibona, Paula. Hospital Italiano. Departamento de Medicina. Servicio de Clinica Medica.; ArgentinaFil: Beruto, Maria Valeria. No especifíca;Fil: Vallone, Miguel Gabriel. No especifíca;Fil: Vázquez, C.. No especifíca;Fil: Savoy, N.. No especifíca;Fil: Giunta, Diego Hernan. No especifíca;Fil: Pérez, L.G.. No especifíca;Fil: Sánchez, M.L.. No especifíca;Fil: Gamarnik, Andrea Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Ojeda, D.S.. No especifíca;Fil: Santoro, D.M.. No especifíca;Fil: Camino, P. J.. No especifíca;Fil: Antelo, S.. No especifíca;Fil: Rainero, K.. No especifíca;Fil: Vidiella, G. P.. No especifíca;Fil: Miyazaki, E. A.. No especifíca;Fil: Cornistein, W.. No especifíca;Fil: Trabadelo, O. A.. No especifíca;Fil: Ross, F. M.. No especifíca;Fil: Spotti, M.. No especifíca;Fil: Funtowicz, G.. No especifíca;Fil: Scordo, W. E.. No especifíca;Fil: Losso, M. H.. No especifíca;Fil: Ferniot, I.. No especifíca;Fil: Pardo, P. E.. No especifíca;Fil: Rodriguez, E.. No especifíca;Fil: Rucci, P.. No especifíca;Fil: Pasquali, J.. No especifíca;Fil: Fuentes, N. A.. No especifíca;Fil: Esperatti, M.. No especifíca;Fil: Speroni, G. A.. No especifíca;Fil: Nannini, Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Inmunología Clinica y Experimental de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Instituto de Inmunología Clinica y Experimental de Rosario; ArgentinaFil: Matteaccio, A.. No especifíca;Fil: Michelangelo, H.G.. No especifíca;Fil: Follmann, D.. No especifíca;Fil: Lane, H. Clifford. No especifíca;Fil: Belloso, Waldo Horacio. Hospital Italiano. Departamento de Medicina. Servicio de Clinica Medica.; Argentin
Increased indoleamine-2,3-dioxygenase activity is associated with poor clinical outcome in adults hospitalized with influenza in the INSIGHT FLU003Plus study
BACKGROUND:
Indoleamine-2,3-dioxygenase (IDO) mediated tryptophan (TRP) depletion has antimicrobial and immuno-regulatory effects. Increased kynurenine (KYN)-to-TRP (KT) ratios, reflecting increased IDO activity, have been associated with poorer outcomes from several infections.
METHODS:
We performed a case-control (1:2; age and sex matched) analysis of adults hospitalized with influenza A(H1N1)pdm09 with protocol-defined disease progression (died/transferred to ICU/mechanical ventilation) after enrollment (cases) or survived without progression (controls) over 60 days of follow-up. Conditional logistic regression was used to analyze the relationship between baseline KT ratio and other metabolites and disease progression.
RESULTS:
We included 32 cases and 64 controls with a median age of 52 years; 41% were female, and the median durations of influenza symptoms prior to hospitalization were 8 and 6 days for cases and controls, respectively (P = .04). Median baseline KT ratios were 2-fold higher in cases (0.24 mM/M; IQR, 0.13-0.40) than controls (0.12; IQR, 0.09-0.17; P ≤ .001). When divided into tertiles, 59% of cases vs 20% of controls had KT ratios in the highest tertile (0.21-0.84 mM/M). When adjusted for symptom duration, the odds ratio for disease progression for those in the highest vs lowest tertiles of KT ratio was 9.94 (95% CI, 2.25-43.90).
CONCLUSIONS:
High KT ratio was associated with poor outcome in adults hospitalized with influenza A(H1N1)pdm09. The clinical utility of this biomarker in this setting merits further exploration.
CLINICALTRIALSGOV IDENTIFIER:
NCT01056185
Effects of Intermittent IL-2 Alone or with Peri-Cycle Antiretroviral Therapy in Early HIV Infection: The STALWART Study
The Study of Aldesleukin with and without antiretroviral therapy (STALWART) evaluated whether intermittent interleukin-2 (IL-2) alone or with antiretroviral therapy (ART) around IL-2 cycles increased CD4+ counts compared to no therapy
Circulating microRNAs in sera correlate with soluble biomarkers of immune activation but do not predict mortality in ART treated individuals with HIV-1 infection: A case control study
Introduction: The use of anti-retroviral therapy (ART) has dramatically reduced HIV-1 associated morbidity and mortality. However, HIV-1 infected individuals have increased rates of morbidity and mortality compared to the non-HIV-1 infected population and this appears to be related to end-organ diseases collectively referred to as Serious Non-AIDS Events (SNAEs). Circulating miRNAs are reported as promising biomarkers for a number of human disease conditions including those that constitute SNAEs. Our study sought to investigate the potential of selected miRNAs in predicting mortality in HIV-1 infected ART treated individuals. Materials and Methods: A set of miRNAs was chosen based on published associations with human disease conditions that constitute SNAEs. This case: control study compared 126 cases (individuals who died whilst on therapy), and 247 matched controls (individuals who remained alive). Cases and controls were ART treated participants of two pivotal HIV-1 trials. The relative abundance of each miRNA in serum was measured, by RTqPCR. Associations with mortality (all-cause, cardiovascular and malignancy) were assessed by logistic regression analysis. Correlations between miRNAs and CD4+ T cell count, hs-CRP, IL-6 and D-dimer were also assessed. Results: None of the selected miRNAs was associated with all-cause, cardiovascular or malignancy mortality. The levels of three miRNAs (miRs -21, -122 and -200a) correlated with IL-6 while miR-21 also correlated with D-dimer. Additionally, the abundance of miRs -31, -150 and -223, correlated with baseline CD4+ T cell count while the same three miRNAs plus miR- 145 correlated with nadir CD4+ T cell count. Discussion: No associations with mortality were found with any circulating miRNA studied. These results cast doubt onto the effectiveness of circulating miRNA as early predictors of mortality or the major underlying diseases that contribute to mortality in participants treated for HIV-1 infection
Experimental confirmation of efficient island divertor operation and successful neoclassical transport optimization in Wendelstein 7-X
Sanificação e eliminação do excesso de líquidos em laranja 'Pêra' minimamente processada
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