Calculation of the aerodynamic characteristics of tapered wings with partial-span flaps

Factors derived from wing theory are presented. By means of these factors, the angle of zero lift, the lift-curve slope, the pitching moment, the aerodynamic-center position, and the induced drag of tapered wings with partial-span flaps may be calculated. The factors are given for wings of aspect ratios 6 and 10 , of taper ratios from 0.25 to 1.00, and with flaps of various length. An example is presented of the method of application of the factors. Fair agreement with experimental results is shown for two wings of different taper ratio having plain flaps of various spacing

Future Decreases in Freezing Days across North America

This study used air temperatures from a suite of regional climate models participating in the North American Climate Change Assessment Program (NARCCAP) together with two atmospheric reanalysis datasets to investigate changes in freezing days (defined as days with daily average temperature below freezing) likely to occur between 30-yr baseline (1971–2000) and midcentury (2041–70) periods across most of North America. Changes in NARCCAP ensemble mean winter temperature show a strong gradient with latitude, with warming of over 4°C near Hudson Bay. The decline in freezing days ranges from less than 10 days across north-central Canada to nearly 90 days in the warmest areas of the continent that currently undergo seasonally freezing conditions. The area experiencing freezing days contracts by 0.9–1.0 × 106 km2 (5.7%–6.4% of the total area). Areas with mean annual temperature between 2° and 6°C and a relatively low rate of change in climatological daily temperatures (−) near the time of spring thaw will encounter the greatest decreases in freezing days. Advances in the timing of spring thaw will exceed the delay in fall freeze across much of the United States, with the reverse pattern likely over most of Canada

Low engagement in HIV services and progress through the treatment cascade among key populations living with HIV in Mozambique : alarming gaps in knowledge of status

Background: Mozambique has a generalized HIV epidemic of 13.5% among the general population. Early modeling exercises in Mozambique estimate that key populations (KP), defined as men who have sex with men (MSM), female sex workers (FSW), and people who inject drugs (PWID), along with their partners account for about one third of all new infections. There is limited data describing the engagement of KP living with HIV in testing, care and treatment services. Methods: We conducted a secondary data analysis of HIV-positive participants in the first Bio-behavioral Surveillance (BBS) surveys in Mozambique conducted 2011–2014 in order to assess service uptake and progress though the HIV treatment cascade among MSM, FSW, and PWID. Unweighted pooled estimates were calculated for each key population group. Results: Among HIV-positive MSM, 63.2% of participants had ever received an HIV test, 8.8% were aware of their status, 6.1% reported having been linked to care, while 3.5% initiated ART and were currently on treatment. Of the HIV-infected FSW participants, 76.5% reported a previous HIV test and 22.4% were previously aware of their status. Linkage to care was reported by 20.1%, while 12.7% reported having initiated ART and 11.8% reported being on treatment at the time of the survey. Among HIV-infected PWID participants, 79.9% had previously received an HIV test, 63.2% were aware of their HIV status, and 49.0% reported being linked to care for their HIV infection. ART initiation was reported by 42.7% of participants, while 29.4% were on ART at the time of the survey. Conclusion: Among the three high risk populations in Mozambique, losses occurred throughout critical areas of service uptake with the most alarming breakpoint occurring at knowledge of HIV status. Special attention should be given to increasing HIV testing and linkage to ART treatment. Future surveys will provide the opportunity to monitor improvements across the cascade in line with global targets and should include viral load testing to guarantee a more complete picture of the treatment cascade

Young key populations left behind: The necessity for a targeted response in Mozambique

Introduction: The first exposure to high-risk sexual and drug use behaviors often occurs during the period of youth (15–24 years old). These behaviors increase the risk of HIV infection, especially among young key populations (KP)–men how have sex with men (MSM), female sex workers (FSW), and people who inject drugs (PWID). We describe the characteristics of young KP participants in the first Biobehavioral Surveillance (BBS) surveys conducted in Mozambique and examine their risk behaviors compared to adult KP. Methods: Respondent-driven sampling (RDS) methodology was used to recruit KP in three major urban areas in Mozambique. RDS-weighted pooled estimates were calculated to estimate the proportion of young KP residing in each survey city. Unweighted pooled estimates of risk behaviors were calculated for each key population group and chi-square analysis assessed differences in proportions between youth (aged less than 24 years old) and older adult KP for each population group. Results: The majority of MSM and FSW participants were young 80.7% (95% CI: 71.5–89.9%) and 71.9% (95% CI: 71.9–79.5%), respectively, although not among PWID (18.2%, 95% CI: 13.2–23.2%). Young KP were single or never married, had a secondary education level or higher, and low employment rates. They reported lower perception of HIV risk (MSM: 72.3% vs 56.7%, p\u3c0.001, FSW: 45.3% vs 24.4%, p\u3c0.001), lower HIV testing uptake (MSM: 67.5% vs 72.3%, p\u3c0.001; FSW: 63.2% vs 80.6%; p\u3c0.001, PWID: 53.3% vs 31.2%; p = 0.001), greater underage sexual debut (MSM: 9.6% vs 4.8%, p\u3c0.001; FSW: 35.2% vs 22.9%, p\u3c0.001), and greater underage initiation of injection drug use (PWID: 31.9% vs 7.0%, p\u3c0.001). Young KP also had lower HIV prevalence compared to older KP: MSM: 3.3% vs 27.0%, p\u3c0.001; FSW: 17.2% vs 53.7%, p\u3c0.001; and PWID: 6.0% vs 55.0%, p\u3c0.001. There was no significant difference in condom use across the populations. Conclusion: There is an immediate need for a targeted HIV response for young KP in Mozambique so that they are not left behind. Youth must be engaged in the design and implementation of interventions to ensure that low risk behaviors are sustained as they get older to prevent HIV infection

Recognizing the hidden : strengthening the HIV surveillance system among key and priority populations in Mozambique

High quality, representative data from HIV surveillance systems that have country ownership and commitment are critical for guiding national HIV responses, especially among key and priority populations given their disproportionate role in the transmission of the virus. Between 2011 to 2013, the Mozambique Ministry of Health has conducted five Biobehavioral Surveillance Surveys among key populations (female sex workers, men who has sex with men and people who inject drugs) and priority populations (long distance truck drives and miners) as part of the national HIV surveillance system. We describe the experience of strengthening the HIV surveillance system among those populations through the implementation of these surveys in Mozambique. We document the lessons learned through the impact on coordination and collaboration; workforce development and institutional capacity building; data use and dissemination; advocacy and policy impact; financial sustainability and community impact. Key lessons learned include the importance of multisectoral collaboration, vital role of data to support key populations visibility and advocacy efforts, and institutional capacity building of government agencies and key populations organizations. Given that traditional surveillance methodologies from routine data often do not capture these hidden populations, it will be important to ensure that Biobehavioral Surveillance Surveys are an integral part of ongoing HIV surveillance activities in Mozambique

Prevalence and risk factors associated with HIV/hepatitis B and HIV/hepatitis C co-infections among people who inject drugs in Mozambique

Background: There is scare information about HIV co-infections with hepatitis B virus (HBV) and/or hepatitis C virus (HCV) among People Who Inject Drugs (PWID) in Mozambique. This information is critical to ensure the treatment necessary to decrease the progression of liver disease and the transmission of both HIV and hepatitis. We assess the prevalence of HIV, HBV and HCV co-infections as well as associated risk factors among PWID. Methods: The first Bio-Behavioral Surveillance Survey was conducted in 2013-2014 among persons who self-reported to have ever injected drugs. Using respondent-driven sampling, PWID aged 18 years and older were recruited in two cross-sectional samples in Maputo and Nampula/Nacala, two large urban centers of Mozambique. Rapid screening of HIV, HBV (HBsAg) and HCV was performed on site. Data from participants in both cities were pooled to conduct RDS-weighted bivariate analyses with HIV/HBV and HIV/HCV co-infections as separate outcomes. Unweighted bivariate and multivariate logistic regression analyses were conducted to assess correlates of co-infection. Results: Among 492 eligible PWID, 93.3% were male and median age was 32 years [IQR: 27-36]. HIV, HBV and HCV prevalence were respectively 44.9% (95% CI:37.6-52.3), 32.8% (95% CI:26.3-39.5) and 38.3 (95% CI:30.6-45.9). Co-infections of HIV/HBV, HIV/HCV and HIV/HBV/HCV were identified in 13.1% (95% CI:7.2-18.9), 29.5% (95% CI:22.2-36.8) and 9.2% (95% CI:3.7-14.7) of PWID, respectively. Older age, history of needle/syringe sharing and history of injection with used needle/syringe was associated with HIV/HBV co-infection. Living in Maputo city, have older age, history of needle/syringe sharing and history of injection with used needle/syringe was associated with HIV/HCV co-infection. Conclusion: There is a high burden of HBV and HCV among HIV-infected PWID in Mozambique. Our results highlight the need for targeted harm reduction interventions that include needle exchange programs and integrated services for the diagnosis and treatment of HIV, HBV and HCV to address these epidemics among PWID. Efforts should be made to strengthen ART coverage in the population as an important treatment strategy for both viruses

Photospheric Abundances of the Hot Stars in NGC1399 and Limits on the Fornax Cluster Cooling Flow

We present far-UV spectroscopy of the giant elliptical galaxy NGC 1399, obtained with the Far Ultraviolet Spectroscopic Explorer. Of all quiescent ellipticals, NGC 1399 has the strongest known ``UV upturn'' -- a sharp spectral rise shortward of 2500 A. It is now well-established that this emission comes from hot horizontal branch (HB) stars and their progeny; however, the chemical composition of these stars has been the subject of a long-standing debate. For the first time in observations of any elliptical galaxy, our spectra clearly show photospheric metallic absorption lines within the UV upturn. The abundance of N is at 45% solar, Si is at 13% solar, and C is at 2% solar. Such abundance anomalies are a natural consequence of gravitational diffusion. These photospheric abundances fall in the range observed for subdwarf B stars of the Galactic field. Although NGC1399 is at the center of the Fornax cluster, we find no evidence for O VI cooling flow emission. The upper limit to 1032,1038 emission is 3.9E-15 erg/s/cm2, equivalent to 0.14 M_sun/yr, and less than that predicted by simple cooling flow models of the NGC 1399 X-ray luminosity.Comment: 4 pages, Latex. 2 figures. Uses corrected version of emulateapj.sty and apjfonts.sty (included). Accepted for publication in ApJ Letters. Revised figure placemen

Electrophysiologic actions of high plasma concentrations of propranolol in human subjects

The authors have previously shown that 40% of patients whose ventricular arrhythmias respond to propranolol require plasma concentrations in excess of those producing substantial beta-receptor blockade (> 150 ng/ml). However, the electrophysiologic actions of propranolol have only been examined in human beings after small intravenous doses achieving concentrations of less than 100 ng/ml. In this study, the electrophysiologic effects of a wider concentration range of propranolol was examined in nine patients. Using a series of loading and maintenance infusions, measurements were made at baseline, at low mean plasma propranolol concentrations (104 ± 17 ng/ml) and at high concentrations (472 ± 68 ng/ml). Significant (p < 0.05) increases in AH interval and sinus cycle length were seen at low concentrations of propranolol, with no further prolongation at the high concentrations; these effects are typical of those produced by beta-blockade. However, progressive shortening of the endocardial monophasic action potential duration and QTc interval were seen over the entire concentration range tested (p < 0.05). At high concentrations, there was significant (p < 0.05) further shortening of both the QTc and monophasic action potential duration beyond that seen at low propranolol concentrations, along with a progressive increase in the ratio of the ventricular effective refractory period to monophasic action potential duration. No significant changes were seen in HV interval, QRS duration or ventricular effective refractory period.In summary, the concentration-response relations for atrioventricular conductivity and sinus node automat-icity were flat above concentrations of 150 ng/ml. On the other hand, the durations of the monophasic action potential and the QTc interval shortened at high concentrations. It is concluded that propranolol, in addition to blocking beta-receptors, produces other beta-receptor independent electrophysiologic effects in human beings