3,222 research outputs found
Universality for Black Hole Heat Engines Near Critical Points
Johnson has shown [arXiv:1703.06119] that in the vicinity of a critical point
the efficiency of a black hole heat engine can approach the Carnot efficiency
while maintaining finite power. We characterize and extend this result in
several ways, and we show how the rate of approach to the Carnot efficiency is
governed by the critical exponents. We apply these results to several classes
of black holes to illustrate their validity. Odd-order Lovelock black holes are
known to have isolated critical points for which the critical exponents differ
from the mean field theory values, providing a non-trivial test of the results.
In this case, our results indicate the impossibility of even-order Lovelock
black holes with isolated critical points in this class: their existence would
constitute a violation of the second law of thermodynamics.Comment: 23 pages, 1 figur
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Lipoprotein particles in patients with pediatric Cushing disease and possible cardiovascular risks.
BackgroundCardiovascular (CV) complications are the most significant cause of mortality in adults with Cushing disease (CD); little is known about CV risk factors in children with CD. Measurement of lipoprotein particles by nuclear magnetic resonance (NMR) spectroscopy is a novel technology to assess CV risk. The objective of the current study is to analyze the NMR lipid profile in pediatric CD patients before and 1 year after remission.MethodsNMR lipid profile was obtained via the Vantera NMR analyzer, using frozen serum samples from 33 CD patients (mean age 13.8 ± 4.0 years) evaluated between 1997 and 2017 at the National Institutes of Health (NIH) Clinical Center (CC).ResultsGlycA (glycosylated acute-phase proteins), triglyceride-rich particles (TRLP medium and very small sizes), low-density lipoprotein (LDL) particles (LDLP total and large size), high-density lipoprotein (HDL) particles (HDLP total, medium and small sizes), total cholesterol, LDL-cholesterol, HDL-cholesterol, GlycA inflammatory biomarker, and apolipoprotein B and apolipoprotein A1 (ApoA1) concentrations showed statistically significant changes after remission of CD (p < 0.05).ConclusionIn our study population, most of the lipid variables improved post-CD remission, with the exception of HDL and ApoA1, indicating that NMR lipoprotein profile may be a helpful tool in assessing the CV risk in pediatric patients with CD
Foreskin trapped by zipper: a case report
We present an 84 year-old-male patient with foreskin trapped by his zipper. After several failed attempts with scissors, screwdriver and others we practise an elliptic incision to resolve the problem. Foreskin injuries are frequent in children but are rare in adult men. There are some techniques described for solving the problem using scissors, screwdriver, traction and surgery
Removal of the hormones 17β-estradiol and 17α-ethinylestradiol from aqueous solutions employing a decomposed peat as adsorbent material
REMOVAL OF THE HORMONES 17b-ESTRADIOL AND 17a-ETHINYLESTRADIOL FROM AQUEOUS SOLUTIONS
EMPLOYING A DECOMPOSED PEAT AS ADSORBENT MATERIAL. This paper describes the adsorption of 17b-estradiol (E2)
and 17a-ethinylestradiol (EE2) from aqueous solution by decomposed peat. The peat presented a good adsorption process, close to
76.2% for E2 removal and approximately 55.0% for EE2. Moreover, the results indicated a probable multi-layered process. Adsorption
isotherms were well fitted by Freundlich model. The data were evaluated considering the pseudo-first-order and pseudo-second-order
approaches, being the second more significant mechanism in the rate-controlling step. Thermodynamic data revealed that hormones
adsorption onto peat is spontaneous under the employed experimental conditions. The results confirmed the potential of this adsorbent
to be employed for effluents treatment
Sleep and diet quality in adolescents
Background: Inability to sleep increases the vulnerability of overeating in particular high calorie density foods considering the current obesogenic environment. In addition, scientific research has shown that a healthy and balanced diet positively influences sleep quality. Objectives: This study aimed to evaluate the quality of sleep of adolescents in the county of Bragança and its association with diet quality. Methods: It was carry out the study in a population of 345 high school students. The data was collected in May 2017 through a questionnaire that included the Pittsburgh Sleep Quality Index (PSQI), by Ramalho (2008). Results: Throughout the study and following PSQI analysis, it was concluded that 39.71% (n=137) of participants showed poor quality of sleep (PSQI >5 points). The correlation between sleep quality and diet quality was assessed and a statistically significant association was found between the quality of sleep and the intake of snacks (X2=17.144; p≤0.001), sugary products (X2=18.603; p=0.000), fast-food (X2=12.353; p=0.002) and ready meals (X2=14.852; p≤0.001). The risk of suffering from poor sleep quality is higher in young populations who frequently eat snacks ([OR]: 2.811; 99%), sugary products ([OR]: 1.901; 95%), fast-food ([OR]: 4.000; 99%) and ready meals ([OR]: 5.621; 95%) in comparison with young populations who rarely eat this sort of food. The sleep quality is also significantly related to the number of correct eating habits (test t = 4.857, p≤0.001). Adolescents with good sleep quality presented a greater number of correct eating habits (mean: 7.85) compared to students with poor sleep quality (mean: 6.55). Conclusions: Through the analysis of the results, the correlation between sleep quality and dietary quality is evident. The risk of having poor quality of sleep is higher in students who frequently eat a high calorie diet and also in students who have fewer healthy eating habits.info:eu-repo/semantics/publishedVersio
Impact of Hot Environment on Fluid and Electrolyte Imbalance, Renal Damage, Hemolysis, and Immune Activation Postmarathon
Previous studies have demonstrated the physiological changes induced by exercise exposure in hot environments. We investigated the hematological and oxidative changes and tissue damage induced by marathon race in different thermal conditions. Twenty-six male runners completed the São Paulo International Marathon both in hot environment (HE) and in temperate environment (TE). Blood and urine samples were collected 1 day before, immediately after, 1 day after, and 3 days after the marathon to analyze the hematological parameters, electrolytes, markers of tissue damage, and oxidative status. In both environments, the marathon race promotes fluid and electrolyte imbalance, hemolysis, oxidative stress, immune activation, and tissue damage. The marathon runner’s performance was approximately 13.5% lower in HE compared to TE; however, in HE, our results demonstrated more pronounced fluid and electrolyte imbalance, renal damage, hemolysis, and immune activation. Moreover, oxidative stress induced by marathon in HE is presumed to be related to protein/purine oxidation instead of other oxidative sources. Fluid and electrolyte imbalance and protein/purine oxidation may be important factors responsible for hemolysis, renal damage, immune activation, and impaired performance after long-term exercise in HE. Nonetheless, we suggested that the impairment on performance in HE was not associated to the muscle damage and lipoperoxidation
Diagnosis of solid waste management in the petrochemical-plastic sector of Cartagena de indias, Northern Colombia
In the production of most petrochemical products there is a generation of associated solid waste. The objective is to diagnose solid waste management in a company in the petrochemical-plastic sector. The methodology initially consisted in the identification of the different operational areas and type of waste under the NTC GTC 24, in the second instance the solid waste classification was carried out taking into account the simple method of analysis of CEPIS and finally the quantification of The waste taking as a reference what Ruiz (2012)[1] did. It is evident that there is an increase (10.2%) in the generation of solid waste generated, from 545,750 kg in 2013 to 601,492 kg in 2014. The activities with the largest generation of solid waste (cardboard, plastic, wood) Are those of the reception and storage processes and the packaging process in each of the plants
Identification of genomic regions associated with morphological traits in Murciano-Granadina goats
Resumen del póster presentado a la 37th International Conference on Animal Genetics (ISAG), celebrada en Lleida (España) del 7 al 12 de julio de 2019.Morphological traits are of great importance to dairy goat production given their strong incidence on milk yield and longevity. However, their genomic architecture has not yet been extensively characterized. Murciano-Granadina is one of the most important goat dairy breeds in Spain, and its breeding program includes the measurement of 17 morphological traits related to udder, feet and body conformation. Our aim was to identify genomic regions associated with these 17 different morphological traits by performing a genome-wide association analysis (GWAS). A total of 722 Murciano-Granadina female goats with linear
evaluation records of each morphological trait were genotyped with the Goat SNP50 BeadChip. Raw phenotypes were corrected for fixed factors (farm, age, number of births and milking stage at the scoring date). After quality control of the data, genome-wide association analyses and chromosome-wide association analyses were performed by using the genome-wide efficient mixed-model association (GEMMA) software. We found no significant associations between the typed SNPs and the studied traits at the genome-wide level. However, the chromosome-wide analysis made possible to identify 3 SNPs associated with
diameter and positioning of the nipples in chromosomes 26 and 28. Interestingly, one significant SNP on chromosome 26 was located downstream
the FGFBP3 gene, which modulates FGFR signaling, one of the main pathways determining the proper development of mammary stem cells. With regard to body conformation, SNPs on chromosome 17 were found to be associated with the chest width. These SNPs mapped to the genes ZNF268 and ZNF827, which encode zinc finger proteins playing important roles in cell growth, proliferation, development, apoptosis, and intracellular signal transduction. Our results suggest a strong additive polygenic background for these morphological traits since we were unable to identify any region on the genome with major effects on their phenotypic variance
Estimating the impact of a gender-neutral quadrivalent human papillomavirus vaccination program in all hpv 6/11/16/18 -related diseases in Colombia
We assessed the public health and economic impact of adding males to the existing female-only quadrivalent HPV vaccine (4vHPV) program in Colombia, analyzing different gender-neutral vaccination (GNV) vaccine coverage rates (VCRs). A published HPV-type dynamic transmission model was used to compare female-only vaccination (FOV) versus GNV with two-dose 4vHPV in the 9-10-year-old cohort over a 100-year timeframe in Colombia. The model compared 35% VCR for FOV with GNV at VCRs of 35% (scenario A), 50% (scenario B) and different VCRs between females/males (50%/35%, scenario C). The predicted health outcomes included HPV 6/11/16/18-related disease and deaths averted [cervical intraepithelial neoplasia, cervical, vaginal, vulvar, penile, anal and head and neck cancers, genital warts (GW), and recurrent respiratory papillomatosis], direct healthcare cost prevented by vaccination, and incremental cost-effectiveness ratios (ICERs). All GNV scenarios are estimated to provide faster and greater reductions in HPV 6/11/16/18-related diseases relative to FOV at 35% VCR, mainly scenarios B and C. The highest cumulative reductions in the incidence of HPV 6/11/16/18-related disease and deaths were seen in scenario B relative to FOV at 35% VCR at year 100, averting 28,001 cervical cancer (CC) cases, 11,968 non-CC cases (4,753 in females and 7,215 in males) and 15,141 deaths. The greatest projected reductions in health care costs are due to diseases caused by HPV-6/11 infection, driven by GW. The cost savings varied from 88 (scenario A) to 184 million (scenario B) relative to FOV at 35%. The ICER for all scenarios was <0, indicating that under the model assumptions it is cost-saving to implement a GNV-4vHPV in Colombia. In Colombia, a GNV-4vHPV program is a cost-saving strategy in the three scenarios analyzed relative to the current FOV program and result in greater improvement of the public health and economic impact in both women and men
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