710 research outputs found
Recurrent Acute Decompensated Heart Failure Admissions for Patients With Reduced Versus Preserved Ejection Fraction (from the Atherosclerosis Risk in Communities Study)
Hospitals are required to report all-cause 30-day readmissions for patients discharged with heart failure. Same-cause readmissions have received less attention but may differ for heart failure with reduced ejection fraction (HFrEF) versus heart failure with preserved ejection fraction (HFpEF). The ARIC study began abstracting medical records for cohort members hospitalized with acute decompensated heart failure (ADHF) in 2005. ADHF was validated by physician review, with HFrEF defined by ejection fraction <50%. Recurrent admissions for ADHF were analyzed within 30 days, 90 days, 6 months, and 1 year of the index hospitalization using repeat-measures Cox regression models. All recurrent ADHF admissions per patient were counted rather than the more typical analysis of only the first occurring readmission. From 2005 to 2014, 1,133 cohort members survived at least 1 hospitalization for ADHF and had ejection fraction recorded. Half were classified as HFpEF. Patients with HFpEF were more often women and had more co-morbidities. The overall ADHF readmission rate was greatest within 30 days of discharge but was higher for patients with HFrEF (115 vs 88 readmissions per 100 person-years). After adjustments for demographics, year of admission, and co-morbidities, there was a trend for higher ADHF readmissions with HFrEF, relative to HFpEF, at 30 days (hazard ratio [HR] 1.41, 95% confidence interval [CI] 0.92 to 2.18), 90 days (HR 1.39, 95% CI 1.05 to 1.85), 6 months (HR 1.47, 95% CI, 1.18 to 1.84), and 1 year (HR 1.42, 95% CI 1.18 to 1.70) of follow-up. In conclusion, patients with HFrEF have a greater burden of short- and long-term readmissions for recurrent ADHF
The structure and dynamics of young star clusters: King 16, NGC 1931, NGC 637 and NGC 189
In this paper, using 2MASS photometry, we study the structural and dynamical
properties of four young star clusters viz. King 16, NGC 1931, NGC 637 and NGC
189. For the clusters King 16, NGC 1931, NGC 637 and NGC 189, we obtain the
limiting radii of 7', 12', 6' and 5' which correspond to linear radii of 3.6
pc, 8.85 pc, 3.96 pc and 2.8 pc respectively. The reddening values
obtained for the clusters are 0.85, 0.65--0.85, 0.6 and 0.53 and their true
distances are 1786 pc, 3062 pc, 2270 pc and 912 pc respectively. Ages of the
clusters are 6 Myr, 4 Myr, 4 Myr and 10 Myr respectively. We compare their
structures, luminosity functions and mass functions () to the parameter to study the star
formation process and the dynamical evolution of these clusters. We find that,
for our sample, mass seggregation is observed in clusters or their cores only
when the ages of the clusters are comparable to their relaxation times (). These results suggest mass seggregation due to dynamical effects. The
values of , which characterise the overall mass functions for the
clusters are 0.96 0.11, 1.16 0.18, 0.55 0.14 and 0.66
0.31 respectively. The change in as a function of radius is a good
indicator of the dynamical state of clusters.Comment: Accepted for publication in Astrophysics & Space Scienc
Loss of the RNA polymerase III repressor MAF1 confers obesity resistance.
MAF1 is a global repressor of RNA polymerase III transcription that regulates the expression of highly abundant noncoding RNAs in response to nutrient availability and cellular stress. Thus, MAF1 function is thought to be important for metabolic economy. Here we show that a whole-body knockout of Maf1 in mice confers resistance to diet-induced obesity and nonalcoholic fatty liver disease by reducing food intake and increasing metabolic inefficiency. Energy expenditure in Maf1(-/-) mice is increased by several mechanisms. Precursor tRNA synthesis was increased in multiple tissues without significant effects on mature tRNA levels, implying increased turnover in a futile tRNA cycle. Elevated futile cycling of hepatic lipids was also observed. Metabolite profiling of the liver and skeletal muscle revealed elevated levels of many amino acids and spermidine, which links the induction of autophagy in Maf1(-/-) mice with their extended life span. The increase in spermidine was accompanied by reduced levels of nicotinamide N-methyltransferase, which promotes polyamine synthesis, enables nicotinamide salvage to regenerate NAD(+), and is associated with obesity resistance. Consistent with this, NAD(+) levels were increased in muscle. The importance of MAF1 for metabolic economy reveals the potential for MAF1 modulators to protect against obesity and its harmful consequences
Macrosegregation During Dendritic Arrayed Growth of Hypoeutectic Pb-Sn Alloys: Influence of Primary Arm Spacing and Mushy Zone Length
Thermosolutal convection in the dendritic mushy zone occurs during directional solidification of hypoeutectic lead tin alloys in a positive thermal gradient, with the melt on the top and the solid below. This results in macrosegregation along the length of the solidified samples. The extent of macrosegregation increases with increasing primary dendrite spacings for constant mushy zone length. For constant primary spacings, the macrosegregation increases with decreasing mushy zone length. Presence of convection reduces the primary dendrite spacings. However, convection in the interdendritic melt has significantly more influence on the spacings as compared with that in the overlying melt, which is caused by the solutal buildup at the dendrite tips
The Labour of Love: Seasonal Migration from Jharkhand to the Brick Kilns of Other States in India
Seasonal casual labour migration in India has conventionally been understood as the result of extreme poverty whereby villagers are forced to become migrants for the dry six months to subsist or merely survive. This article draws on fieldwork in a village in Jharkhand and a brick kiln in West Bengal to argue that migrants do not understand their movement in economic terms alone. Many see the brick kilns as a temporary space of freedom to escape problems back home, explore a new country, gain independence from parents or live out prohibited amorous relationships. It is suggested that Jharkhandi activists and policy-makers’ construction of such migration as a ‘problem’ is as much about their vision of how the new tribal state ought to be as about exploitation. Migration to the kilns is seen by them as a threat to the purity and regulation of the social and sexual tribal citizen. This moralising perspective creates a climate that paradoxically encourages many young people to flee to the brick kilns where they can live ‘freely’. In this way, the new puritanism at home helps to reproduce the conditions for capitalist exploitation and the extraction of surplus value
Ethics of controlled human infection to study COVID-19
Development of an effective vaccine is the clearest path to controlling the coronavirus disease 2019 (COVID-19) pandemic. To accelerate vaccine development, some researchers are pursuing, and thousands of people have expressed interest in participating in, controlled human infection studies (CHIs) with severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2) (1, 2). In CHIs, a small number of participants are deliberately exposed to a pathogen to study infection and gather preliminary efficacy data on experimental vaccines or treatments. We have been developing a comprehensive, state-of-the-art ethical framework for CHIs that emphasizes their social value as fundamental to justifying these studies. The ethics of CHIs in general are underexplored (3, 4), and ethical examinations of SARS-CoV-2 CHIs have largely focused on whether the risks are acceptable and participants could give valid informed consent (1). The high social value of such CHIs has generally been assumed. Based on our framework, we agree on the ethical conditions for conducting SARS-CoV-2 CHIs (see the table). We differ on whether the social value of such CHIs is sufficient to justify the risks at present, given uncertainty about both in a rapidly evolving situation; yet we see none of our disagreements as insurmountable. We provide ethical guidance for research sponsors, communities, participants, and the essential independent reviewers considering SARS-CoV-2 CHIs
Simultaneous Quantitative Analysis of Olmesartan Medoxomil and Amlodipine Besylate in Plasma by High-performance Liquid Chromatography Technique
A rapid, simple and sensitive high-performance liquid chromatography (HPLC) method has been developed for quantification of olmesartan medoxomil (OLM) and amlodipine besylate (AM) in plasma. The assay enables the measurement of OLM and AM for therapeutic drug monitoring with a minimum detectable limit of 2 ng mL. The method involves a simple, one-step extraction procedure and analytical recovery was above 50%. The separation was performed on an analytical 250 × 4.6 mm Eurospher 100-5 C18 column. The wavelength was set at 239 nm. The mobile phase was a mixture of acetonitrile:0.05 M ammonium acetate buffer: 0.1 mL triethylamine at pH 6.8 was selected at a flow rate of 1.0 mL min. The calibration curve for the determination of OLM and AM in plasma was linear over the range 2–2500 and 8–10,000 ng mL AM and OLM. The coefficients of variation for interday and intraday assay were found to be <15%. The method can be applied to a pharmacokinetic and pharmacodynamic study of OLM and AM in a combined dosage form
Suppression of High-p_T Neutral Pion Production in Central Pb+Pb Collisions at sqrt{s_NN} = 17.3 GeV Relative to p+C and p+Pb Collisions
Neutral pion transverse momentum spectra were measured in p+C and p+Pb
collisions at sqrt{s_NN} = 17.4 GeV at mid-rapidity 2.3 < eta_lab < 3.0 over
the range 0.7< p_T < 3.5 GeV/c. The spectra are compared to pi0 spectra
measured in Pb+Pb collisions at sqrt{s_NN} = 17.3 GeV in the same experiment.
For a wide range of Pb+Pb centralities (N_part < 300) the yield of pi0's with
p_T > 2 GeV/c is larger than or consistent with the p+C or p+Pb yields scaled
with the number of nucleon-nucleon collisions (N_coll), while for central Pb+Pb
collisions with N_part > 350 the pi0 yield is suppressed.Comment: 5 pages, 4 figure
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