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Objectives: In this study, we investigated perceptions of prescription opioid misuse among young adults who had or had not been prescribed opioids in the past. Methods: Participants from a national online panel, age 18-34 (N = 1220), completed a survey about their medical use of opioids and their perceptions of the risks and prevalence of opioid misuse and dependence. Associations between prescription history and perceptions of opioids were tested using generalized ordered logistic models. Results:Most respondents reported receiving at least one prescription for opioids in their lifetime (68%), with 57% reporting past-year prescriptions. Re spondents with more lifetime prescriptions perceived higher rates of misuse and dependence. More lifetime prescriptions were associated with lower perceived risk of occasional prescription opioid misuse but higher perceived risk for regular misuse. Conclusions: Prior experience with receiving a prescription for opioid pain relievers is associated with young adults' perceptions of opioid misuse. Taking prescription opioids, even as directed, provides young adults with expo- sure to the drugs that may shape these perceptions both by increasing awareness of the drug and through exposure to misuse of the drug.

A systematic chart review was performed to estimate the frequency of pregnancy outcomes, pregnancy complications and neonatal outcomes at facilities in Blantyre, Malawi; Johannesburg, South Africa; Kampala, Uganda; and Chitungwiza and Harare, Zimbabwe to provide comparisons with estimates from an ongoing clinical trial evaluating the safety of two biomedical HIV prevention interventions in pregnancy. A multi-site, cross-sectional chart review was conducted at Maternal Obstetric Units and hospitals where women participating in the ongoing clinical trial would be expected to deliver. All individuals delivering at the designated facilities or admitted for postpartum care within seven days of a delivery elsewhere (home, health clinic, etc.) were included in the review. Data were abstracted for pregnancy outcomes, pregnancy complications, maternal and neonatal death, and congenital anomalies. Data from 10,138 records were abstracted across all four sites (Blantyre n = 2,384; Johannesburg n = 1,888; Kampala n = 3,708; Chitungwiza and Harare n = 2,158), which included 10,426 pregnancy outcomes. The prevalence of preterm birth was 13% (range across sites: 10.4–20.7) and 4.1% of deliveries resulted in stillbirth (range: 3.1–5.5). The most commonly noted pregnancy complication was gestational hypertension, reported among 4.4% of pregnancies. Among pregnancies resulting in a live birth, 15.5% were low birthweight (range: 13.8–17.4) and 2.0% resulted in neonatal death (range:1.2–3.2). Suspected congenital anomalies were noted in 1.2% of pregnancies. This study provides systematically collected data on background rates of pregnancy outcomes, pregnancy complications and neonatal outcomes that can be used as a reference in support of ongoing HIV prevention studies. In addition, estimates from this study provide important background data for future studies of investigational products evaluated in pregnancy in these urban settings.

Introduction Harm perceptions of menthol cigarettes may contribute to their appeal and use. African-Americans, women, and younger smokers disproportionately use menthol cigarettes, and may misperceive harm of menthol cigarettes. Methods Data were from Wave 1 of the Population Assessment of Tobacco and Health (PATH) Study. Weighted analyses of current adult smokers (18 and older) were used to estimate the correlates of menthol smoking among all cigarette brands and separately for the top three cigarette brands (Newport, Camel, and Marlboro). Adjusted models examined the main effect of menthol smoking on harm perceptions of one's own brand of cigarette and interactions with race/ethnicity, age, and gender. Results Menthol cigarettes were used by nearly 40% of current smokers, although the prevalence of menthol smoking differed across the top three brands (94% Newport, 46% Camel, and 18% Marlboro). Among menthol smokers, 80% perceived their cigarette as equally harmful, 14% perceived their brand as more harmful, and 7% perceived their brand as less harmful. In adjusted models, menthol smokers were more likely than nonmenthol smokers to misperceive their own brand as more harmful than other brands (compared to no difference in harm). Race and gender emerged as moderators of the association between menthol brand preference and harm perceptions. Conclusions In adjusted analyses, menthol smokers were more likely than nonmenthol smokers to perceive their brand as more harmful than other brands, with differences by sub-groups who disproportionately use menthol. Implications Menthol cigarettes have been historically marketed with messages conveying lower harm than other cigarettes. Little is known about how contemporary adult menthol smokers perceive the harm of their usual brand, and potential differences by race, gender, and young adult versus older adult age group. After adjusting for other factors, menthol smokers were more likely than nonmenthol smokers to perceive their cigarette brand as more harmful than other brands. Further, the association between menthol smoking and harm perceptions differed by race and gender, but not by age group (young adult vs. older adult). This type of large-scale study identifies critical links between menthol smoking and harm perceptions among vulnerable smokers that will inform regulatory actions designed to decrease smoking-related harm.

BackgroundAntiretroviral medications that are used as prophylaxis can prevent acquisition of human immunodeficiency virus type 1 (HIV-1) infection. However, in clinical trials among African women, the incidence of HIV-1 infection was not reduced, probably because of low adherence. Longer-acting methods of drug delivery, such as vaginal rings, may simplify use of antiretroviral medications and provide HIV-1 protection. MethodsWe conducted a phase 3, randomized, double-blind, placebo-controlled trial of a monthly vaginal ring containing dapivirine, a non-nucleoside HIV-1 reverse-transcriptase inhibitor, involving women between the ages of 18 and 45 years in Malawi, South Africa, Uganda, and Zimbabwe. ResultsAmong the 2629 women who were enrolled, 168 HIV-1 infections occurred: 71 in the dapivirine group and 97 in the placebo group (incidence, 3.3 and 4.5 per 100 person-years, respectively). The incidence of HIV-1 infection in the dapivirine group was lower by 27% (95% confidence interval [CI], 1 to 46; P=0....

Perceived experiences of discrimination have been linked to negative health behaviors including tobacco, alcohol, and marijuana use across various racial/ethnic groups. Tobacco and alcohol marketing exposure have also been linked with substance use. This study examined the independent and interacting effects of perceived experiences of discrimination and exposure to alcohol and tobacco marketing, and receptivity to marijuana marketing on substance use in an online survey of a multiethnic sample of young adults in 6 metropolitan areas (

Aluminum nitride (AlN) was grown on c-plane sapphire substrates by hydride vapor phase epitaxy (HVPE). The experiments utilized a two zone inductively heated hot-wall reactor capable of temperatures exceeding 1500 °C. The precursors of aluminum monochloride (AlCl) and aluminum trichloride (AlCl3) were used, and it was determined that AlCl3 was more thermodynamically conducive to single crystalline AlN growth at 1450 °C. AlN templates were optimized at a thickness of 1 µm without cracking. The double axis X-ray diffraction (XRD) rocking curves full width half maximums (FWHMs) were reproducibly demonstrated with an average of 130 arcsec for the (002) and 516 arcsec for the (102). The AlN was transparent in the UV spectrum with a band gap cut off of 200 nm. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The benefits of dry oxidation of n -GaN for the fabrication of metal-oxide-semiconductor structures are reported. GaN thin films grown on sapphire by MOCVD were thermally oxidized for 30, 45 and 60 minutes in a pure oxygen atmosphere at 850 °C to produce thin, smooth GaOx layers. The GaN sample oxidized for 30 minutes had the best properties. Its surface roughness (0.595 nm) as measured by atomic force microscopy (AFM) was the lowest. Capacitance-voltage measurements showed it had the best saturation in accumulation region and the sharpest transition from accumulation to depletion regions. Under gate voltage sweep, capacitance-voltage hysteresis was completely absent. The interface trap density was minimum (Dit = 2.75×1010 cm–2eV–1) for sample oxidized for 30 mins. These results demonstrate a high quality GaOx layer is beneficial for GaN MOSFETs. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Semiconducting icosahedral boron arsenide, B 12 As 2 , is an excellent candidate for neutron detectors, thermoelectric converters, and radioisotope batteries, for which high quality single crystals are required. Thus, the present study was undertaken to grow B 12 As 2 crystals by precipitation from metal solutions (nickel) saturated with elemental boron (or B 12 As 2 powder) and arsenic in a sealed quartz ampoule. B 12 As 2 crystals of 10-15 mm were produced when a homogeneous mixture of the three elements was held at 1150 °C for 48-72 h and slowly cooled (3.5 °C/h). The crystals varied in color and transparency from black and opaque to clear and transparent. X-ray topography (XRT), and elemental analysis by energy dispersive X-ray spectroscopy (EDS) confirmed that the crystals had the expected rhombohedral structure and chemical stoichiometry. The concentrations of residual impurities (nickel, carbon, etc.) were low, as measured by Raman spectroscopy and secondary ion mass spectrometry (SIMS). Additionally, low etch-pit densities (4.4 x 10 7 cm ―2 ) were observed after etching in molten KOH at 500 °C. Thus, the flux growth method is viable for growing large, high-quality B 12 As 2 crystals.

Aluminum nitride (AlN) was grown on c -plane sapphire substrates by hydride vapor phase epitaxy (HVPE). The experiments utilized a two zone inductively heated hot-wall reactor. The surface morphology, crystal quality, and growth rate were investigated as a function of growth temperature in the range of 1450–1575 °C. AlN templates grown to a thickness of 1 μm were optimized with double axis X-ray diffraction (XRD) rocking curve full width half maximums (FWHMs) of 135″ for the (002) and 513″ for the (102).

The present work reports on the defect-selective etching (DSE) for estimating dislocation densities in icosahedral boron arsenide (B12As2) crystals using molten potassium hydroxide (KOH). DSE takes advantage of the greater reactivity of high-energy sites surrounding a dislocation, compared to the surrounding dislocation-free regions. The etch pits per area are indicative of the defect densities in the crystals, as confirmed by x-ray topography (XRT). Etch pit densities were determined for icosahedral boron arsenide crystals produced from a molten nickel flux as a function of etch time (1-5 minutes) and temperature (400-700°C). The etch pits were predominately triangle shaped, and ranged in size from 5-25μm. The average etch pit density of the triangle and oval etch-pits was on the order of 5x107cm-2 and 3x106cm-2 (respectively), for crystals that were etched for two minutes at 550°C.

The crystallographic properties of bulk icosahedral boron arsenide (B12As2) crystals grown by precipitation from molten nickel solutions were characterized. Large crystals (5-8 mm) were produced by dissolving the boron in nickel at 1150°C for 48-72 hours, reacting with arsenic vapor, and slowly cooling to room temperature. The crystals varied in color from black and opaque to clear and transparent. Raman spectroscopy, x-ray topography (XRT), and defect selective etching revealed that the B12As2 single crystals were high quality with low dislocation densities. Furthermore, XRT results suggest that the major face of the plate-like crystals was (111) type, while (100), (010) and (001) type facets were also observed optically. The predominant defect in these crystals was edge character growth dislocations with a Burgers vector, and line direction. In short, XRT characterization shows that solution growth is a viable method for producing good quality B12As2 crystals.