Effects of Acoustics on Induced Droplet Shedding In Dropwise Condensation

Research studies over the years have confirmed that dropwise condensation is more effective than film-wise condensation since it promotes higher rates of heat transfer. However, droplet shedding in dropwise condensation still is one of the limiting steps in the overall condensation phenomena, even when using engineered surfaces. Therefore, acoustic stimuli should be considered to promote adequate droplet shedding during condensation. To that end, an acoustic system has been developed to induce droplet shedding via substrate-droplet resonance. To understand the relationship between droplet sliding angle and body forces such as gravity and acoustic streaming, a mathematical model has been postulated capable of predicting the critical sliding angle of droplets. Recently, a mathematical physics-based model has been developed, which can predict droplet-sliding angles while using a variety of surfaces including those with hydrophobic and hydrophilic wetting characteristics. The model has been validated experimentally with and without imposing acoustic stimuli under the influence of gravity. Initially, the relationship between the sliding angle and droplet volume were investigated experimentally to obtain the contact angle hysteresis for smooth surfaces. Then, different natural frequencies of droplets were also examined to determine the best resonance mode of vibration that leads to lower-sliding angles. Experimental data show that the model can be used effectively to relate imposed resonance frequency to critical sliding angle of droplets. Experimental results to date also show that surfaces with hydrophobic properties, depict lower condensation rates than hydrophilic surfaces. Moreover, hydrophobic surfaces depict droplets with less contact area and greater surface area on the vapor side, which lead to greater thermal resistance and lower condensation rates. While imposing vibrations to a condensation system, a surface with super-hydrophobic properties shows an enhancement in heat flux of 45%. Furthermore, heat transfer enhancement in both hydrophilic and hydrophobic surfaces can be achieved when the difference between surface temperature and ambient temperature (T) is in the range of 10 to 12.5 °C. In summary, vibrations help shed smaller droplets faster, which allow for faster rate of dropwise condensation. Furthermore, vibrations help mitigate the effects of surface tension on condensation

Effects of Acoustics on Induced Droplet Shedding In Dropwise Condensation

Research studies over the years have confirmed that dropwise condensation is more effective than film-wise condensation since it promotes higher rates of heat transfer. However, droplet shedding in dropwise condensation still is one of the limiting steps in the overall condensation phenomena, even when using engineered surfaces. Therefore, acoustic stimuli should be considered to promote adequate droplet shedding during condensation. To that end, an acoustic system has been developed to induce droplet shedding via substrate-droplet resonance. To understand the relationship between droplet sliding angle and body forces such as gravity and acoustic streaming, a mathematical model has been postulated capable of predicting the critical sliding angle of droplets. Recently, a mathematical physics-based model has been developed, which can predict droplet-sliding angles while using a variety of surfaces including those with hydrophobic and hydrophilic wetting characteristics. The model has been validated experimentally with and without imposing acoustic stimuli under the influence of gravity. Initially, the relationship between the sliding angle and droplet volume were investigated experimentally to obtain the contact angle hysteresis for smooth surfaces. Then, different natural frequencies of droplets were also examined to determine the best resonance mode of vibration that leads to lower-sliding angles. Experimental data show that the model can be used effectively to relate imposed resonance frequency to critical sliding angle of droplets. Experimental results to date also show that surfaces with hydrophobic properties, depict lower condensation rates than hydrophilic surfaces. Moreover, hydrophobic surfaces depict droplets with less contact area and greater surface area on the vapor side, which lead to greater thermal resistance and lower condensation rates. While imposing vibrations to a condensation system, a surface with super-hydrophobic properties shows an enhancement in heat flux of 45%. Furthermore, heat transfer enhancement in both hydrophilic and hydrophobic surfaces can be achieved when the difference between surface temperature and ambient temperature (T) is in the range of 10 to 12.5 °C. In summary, vibrations help shed smaller droplets faster, which allow for faster rate of dropwise condensation. Furthermore, vibrations help mitigate the effects of surface tension on condensation

Los claroscuros de la sincronización internacional de los ciclos económicos: evidencia sobre la manufactura de México

Se analiza la sincronización de las fluctuaciones cíclicas de la división manufacturera de México con el ciclo estadounidense. Se utiliza el enfoque tradicional de los ciclos de crecimiento para el periodo 1980-2004 en submuestras de cinco años que se desplazan en el tiempo, lo cual permite estudiar la evolución temporal del proceso. Los resultados sugieren que la sincronización se ha incrementado sustancialmente en el marco del TLCAN, pero ha sido heterogénea, pues el comercio exterior puede haber sido un mecanismo de transmisión fundamental en el proceso. También se muestra que las actividades más integradas al exterior son más vulnerables a los choques externos, lo cual puede constituir una debilidad de la nueva estrategia de desarrollo

Intubación de Vía Aérea Difícil con Broncoscopio Flexible

ResumenJustificativa y objetivoDescribir un protocolo de intubación con broncoscopio flexible (FBI, de flexible bronchoscopy intubation) en pacientes con la vía aérea difícil, su eficacia y seguridad. Métodos: Se revisaron las historias clínicas de pacientes diagnosticados con vía aérea difícil y que fueron sometidos a la broncoscopia flexible para la intubación bajo ventilación espontánea y sedación con midazolam y fentanilo, de marzo de 2009 a diciembre de 2010.ResultadosFueron seleccionados 102 pacientes, 69 (67,7%) hombres y 33 (32,3%) mujeres, con una edad promedio de 44 años. En 59 pacientes con vía aérea difícil prevista (57,8%) la FBI se hizo en un centro quirúrgico; 39 (38,2%) ocurrieron en la Unidad de Cuidados Intensivos y cuatro casos (3,9%) en la sala de emergencia. La tos, la caída de saturación de oxígeno transitoria y la dificultad para insertar la cánula a través de la laringe, fueron las principales complicaciones del método, pero no impidieron la intubación.ConclusionesLa FBI, si secunda un protocolo de sedación consciente con midazolam y fentanilo, es eficiente y segura en el manejo de pacientes con vía aérea difícil

Sodium restriction in patients with chronic heart failure and reduced ejection fraction: A randomized controlled trial

Background: Sodium restriction is recommended for patients with heart failure (HF) despite the lack of solid clinical evidence from randomized controlled trials. Whether or not sodium restrictions provide beneficial cardiac effects is not known. Methods: The present study is a randomized, double-blind, controlled trial of stable HF patients with ejection fraction ≤ 40%. Patients were allocated to sodium restriction (2 g of sodium/day) vs. control (3 g of sodium/day). The primary outcome was change in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 20 weeks. Secondary outcomes included quality of life and adverse safety events (HF readmission, blood pressure or electrolyte abnormalities). Results: Seventy patients were enrolled. Median baseline sodium consumption was 3268 (2225–4537) mg/day. Adherence to the intervention based on 24-hour urinary sodium was 32%. NT-proBNP and quality of life did not significantly change between groups (p > 0.05 for both). Adverse safety events were not significantly different between the arms (p > 0.6 for all). In the per protocol analysis, patients who achieved a sodium intake < 2500 mg/day at the  intervention conclusion showed improvements in NT-proBNP levels (between-group difference: –55%, 95% confidence interval –27 to –73%; p = 0.002) and quality of life (between-group difference –11 ± 5 points; p = 0.04). Blood pressure decreased in patients with lower sodium intake (between-group difference –9 ± 5 mmHg; p = 0.05) without significant differences in symptomatic hypotension or other safety events (p > 0.3 for all). Conclusions: Adherence assessed by 24-hour natriuresis and by the nutritionist was poor. The group allocated to sodium restriction did not show improvement in NT-proBNP. However, patients who achieved a sodium intake < 2500 mg/day appeared to have improvements in NT-proBNP and quality of life without any adverse safety signals. ClinicalTrials.gov Identifier: NCT03351283

Global, regional, and national incidence and mortality for HIV, tuberculosis, and malaria during 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013

BACKGROUND: The Millennium Declaration in 2000 brought special global attention to HIV, tuberculosis, and malaria through the formulation of Millennium Development Goal (MDG) 6. The Global Burden of Disease 2013 study provides a consistent and comprehensive approach to disease estimation for between 1990 and 2013, and an opportunity to assess whether accelerated progress has occured since the Millennium Declaration. METHODS: To estimate incidence and mortality for HIV, we used the UNAIDS Spectrum model appropriately modified based on a systematic review of available studies of mortality with and without antiretroviral therapy (ART). For concentrated epidemics, we calibrated Spectrum models to fit vital registration data corrected for misclassification of HIV deaths. In generalised epidemics, we minimised a loss function to select epidemic curves most consistent with prevalence data and demographic data for all-cause mortality. We analysed counterfactual scenarios for HIV to assess years of life saved through prevention of mother-to-child transmission (PMTCT) and ART. For tuberculosis, we analysed vital registration and verbal autopsy data to estimate mortality using cause of death ensemble modelling. We analysed data for corrected case-notifications, expert opinions on the case-detection rate, prevalence surveys, and estimated cause-specific mortality using Bayesian meta-regression to generate consistent trends in all parameters. We analysed malaria mortality and incidence using an updated cause of death database, a systematic analysis of verbal autopsy validation studies for malaria, and recent studies (2010-13) of incidence, drug resistance, and coverage of insecticide-treated bednets. FINDINGS: Globally in 2013, there were 1·8 million new HIV infections (95% uncertainty interval 1·7 million to 2·1 million), 29·2 million prevalent HIV cases (28·1 to 31·7), and 1·3 million HIV deaths (1·3 to 1·5). At the peak of the epidemic in 2005, HIV caused 1·7 million deaths (1·6 million to 1·9 million). Concentrated epidemics in Latin America and eastern Europe are substantially smaller than previously estimated. Through interventions including PMTCT and ART, 19·1 million life-years (16·6 million to 21·5 million) have been saved, 70·3% (65·4 to 76·1) in developing countries. From 2000 to 2011, the ratio of development assistance for health for HIV to years of life saved through intervention was US$4498 in developing countries. Including in HIV-positive individuals, all-form tuberculosis incidence was 7·5 million (7·4 million to 7·7 million), prevalence was 11·9 million (11·6 million to 12·2 million), and number of deaths was 1·4 million (1·3 million to 1·5 million) in 2013. In the same year and in only individuals who were HIV-negative, all-form tuberculosis incidence was 7·1 million (6·9 million to 7·3 million), prevalence was 11·2 million (10·8 million to 11·6 million), and number of deaths was 1·3 million (1·2 million to 1·4 million). Annualised rates of change (ARC) for incidence, prevalence, and death became negative after 2000. Tuberculosis in HIV-negative individuals disproportionately occurs in men and boys (versus women and girls); 64·0% of cases (63·6 to 64·3) and 64·7% of deaths (60·8 to 70·3). Globally, malaria cases and deaths grew rapidly from 1990 reaching a peak of 232 million cases (143 million to 387 million) in 2003 and 1·2 million deaths (1·1 million to 1·4 million) in 2004. Since 2004, child deaths from malaria in sub-Saharan Africa have decreased by 31·5% (15·7 to 44·1). Outside of Africa, malaria mortality has been steadily decreasing since 1990. INTERPRETATION: Our estimates of the number of people living with HIV are 18·7% smaller than UNAIDS's estimates in 2012. The number of people living with malaria is larger than estimated by WHO. The number of people living with HIV, tuberculosis, or malaria have all decreased since 2000. At the global level, upward trends for malaria and HIV deaths have been reversed and declines in tuberculosis deaths have accelerated. 101 countries (74 of which are developing) still have increasing HIV incidence. Substantial progress since the Millennium Declaration is an encouraging sign of the effect of global action. FUNDING: Bill & Melinda Gates Foundation

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV

Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017.

The Global Burden of Diseases, Injuries and Risk Factors 2017 includes a comprehensive assessment of incidence, prevalence, and years lived with disability (YLDs) for 354 causes in 195 countries and territories from 1990 to 2017. Previous GBD studies have shown how the decline of mortality rates from 1990 to 2016 has led to an increase in life expectancy, an ageing global population, and an expansion of the non-fatal burden of disease and injury. These studies have also shown how a substantial portion of the world's population experiences non-fatal health loss with considerable heterogeneity among different causes, locations, ages, and sexes. Ongoing objectives of the GBD study include increasing the level of estimation detail, improving analytical strategies, and increasing the amount of high-quality data. METHODS: We estimated incidence and prevalence for 354 diseases and injuries and 3484 sequelae. We used an updated and extensive body of literature studies, survey data, surveillance data, inpatient admission records, outpatient visit records, and health insurance claims, and additionally used results from cause of death models to inform estimates using a total of 68 781 data sources. Newly available clinical data from India, Iran, Japan, Jordan, Nepal, China, Brazil, Norway, and Italy were incorporated, as well as updated claims data from the USA and new claims data from Taiwan (province of China) and Singapore. We used DisMod-MR 2.1, a Bayesian meta-regression tool, as the main method of estimation, ensuring consistency between rates of incidence, prevalence, remission, and cause of death for each condition. YLDs were estimated as the product of a prevalence estimate and a disability weight for health states of each mutually exclusive sequela, adjusted for comorbidity. We updated the Socio-demographic Index (SDI), a summary development indicator of income per capita, years of schooling, and total fertility rate. Additionally, we calculated differences between male and female YLDs to identify divergent trends across sexes. GBD 2017 complies with the Guidelines for Accurate and Transparent Health Estimates Reporting