Obtaining more accurate and reliable information from adolescents regarding STI/HIV risk behaviors

To investigate the quality of self-reported data on sexual behavior, Population Council researchers conducted a study in a rural district of Malawi. They implemented a randomized experiment to assess whether audio computer-assisted self-interviewing (ACASI) produces more valid data on sexual behavior than face-to-face interviews. The Malawi study builds on an experiment conducted as part of a household-based survey of Kenyan adolescents. In Kenya and Malawi, there is clear evidence that mode of interviewing and probing of various sexual partnerships affect the reporting of sexual activity. According to Promoting Healthy, Safe, and Productive Transitions to Adulthood Brief No. 25, ACASI is a feasible methodology to use in rural areas of sub-Saharan Africa among adolescent populations unfamiliar with computers. Computerized interviewing improves quality of data on highly sensitive behaviors collected from adolescents. Given the importance of data on sexual behavior both in understanding the etiology of the AIDS epidemic and in clinical testing of products and technologies to reduce transmission of sexually transmitted infections, more research is needed on the interaction between interviewers and respondents and on reactions to the computer in developing-country populations

Consistency in the reporting of sexual behavior among adolescent girls in Kenya: A comparison of interviewing methods

This paper explores the consistency in reporting of sexual behavior in a household survey of adolescents aged 15-21 in the Kisumu district of Kenya. Respondents were randomly assigned to different interviewing modes: face-to-face interviews, paper-and-pencil self-administered interviews, and audio computer-assisted self-interviewing (ACASI). The analysis focuses on the reporting of sexual behavior by adolescent girls in the face-to-face and ACASI modes and compares responses to a variety of questions about sexual activity, including sexual initiation, risky sexual behavior, and coerced sex. All sexual behavior questions were asked of each adolescent girl even if she answered “no” to the initial question about ever having had sex. The paper also compares the consistency of reporting for questions that were asked twice during the survey-once in the main interview and again in a face-to-face exit interview. By comparison with ACASI, the interviewer-administered mode produces highly consistent reporting of sexual activity both within the main interview and between the main and exit interviews. On the other hand, ACASI produces higher reporting of sex with a relative, stranger, or older man, and higher reporting of coerced sex. We argue that the level of consistency and the high response rates in the interviewer-administered mode are suspect and suggest reasons why one might expect inconsistent responses to survey questions about sexual behavior

Gating of high-mobility two-dimensional electron gases in GaAs/AlGaAs heterostructures

We investigate high-mobility two-dimensional electron gases in AlGaAs heterostructures by employing Schottky-gate-dependent measurements of the samples' electron density and mobility. Surprisingly, we find that two different sample configurations can be set in situ with mobilities diering by a factor of more than two in a wide range of densities. This observation is discussed in view of charge redistributions between the doping layers and is relevant for the design of future gateable high-mobility electron gases

Feminism and the Staged Uncanny

In my Thesis, I work towards a new definition of the uncanny and show the transformation of its sense in the modern period. I will then show how this transformed sense appears in the media of mechanical reproduction—stage theatrics, photography and film—and, then, specifically in my art practice

Sexual behavior and STI/HIV status among adolescents in rural Malawi: An evaluation of the effect of interview mode on reporting

This paper presents the results from an interview-mode experiment conducted by the Population Council with unmarried young women in rural southern Malawi. To collect data on sexual behavior and the dynamics of HIV transmission, respondents were randomly assigned to either an audio computer-assisted self-interview (ACASI) or a conventional face-to-face (FTF) interview. Clear evidence indicates that the mode of interviewing and probing concerning various sexual partnerships affects respondents’ reporting of their sexual activity, yet the results are not always in accordance with expectations. Reporting for “ever had sex” and “sex with a boyfriend” is higher in the FTF mode, whereas, when we ask about other partners as well as multiple lifetime partners, the reporting is consistently higher with ACASI, in many cases significantly so. The interview-administered mode produced more consistent reporting of sexual activity between the main interview and a subsequent interview. Finally, the association between infection status and reporting of sexual behavior is stronger in the FTF mode, although in both modes, some young women who denied ever having had sex tested positive for STIs/HIV

The (Mis)Reporting of Male Circumcision Status among Men and Women in Zambia and Swaziland: A Randomized Evaluation of Interview Methods

BACKGROUND: To date, male circumcision prevalence has been estimated using surveys of men self-reporting their circumcision status. HIV prevention trials and observational studies involving female participants also collect data on partners' circumcision status as a risk factor for HIV/STIs. A number of studies indicate that reports of circumcision status may be inaccurate. This study assessed different methods for improving self- and partner reporting of circumcision status. METHODS/FINDINGS: The study was conducted in urban and rural Zambia and urban Swaziland. Men (N = 1264) aged 18-50 and their female partners (N = 1264), and boys (N = 840) aged 13-17 were enrolled. Participants were recruited from HIV counseling and testing sites, health centers, and surrounding communities. The study experimentally assessed methods for improving the reporting of circumcision status, including: a) a simple description of circumcision, b) a detailed description of circumcision, c) an illustration of a circumcised and uncircumcised penis, and d) computerized self-interviewing. Self-reports were compared to visual examination. For men, the error in reporting was largely unidirectional: uncircumcised men more often reported they were circumcised (2-7%), depending on setting. Fewer circumcised men misrepresented their status (0.05-5%). Misreporting by women was significantly higher (11-15%), with the error in both directions. A sizable number of women reported that they did not know their partner's circumcision status (3-8%). Computerized interviewing did not improve accuracy. Providing an illustration, particularly for illiterate participants, significantly improved reporting of circumcision status, decreasing misreporting among illiterate participants from 13% to 10%, although misreporting was not eliminated. CONCLUSIONS: Study results suggest that the prevalence of circumcision may be overestimated in Zambia and Swaziland; the error in reporting is higher among women than among men. Improved reporting when a description or illustration is provided suggests that the source of the error is a lack of understanding of male circumcision

Solution structure of Mannobioses unravelled by means of Raman optical activity

Structural analysis of carbohydrates is a complicated endeavour, due to the complexity and diversity of the samples at hand. Herein, we apply a combined computational and experimental approach, employing molecular dynamics (MD) and density functional theory (DFT) calculations together with NMR and Raman optical activity (ROA) measurements, in the structural study of three mannobiose disaccharides, consisting of two mannoses with varying glycosidic linkages. The disaccharide structures make up the scaffold of high mannose glycans and are therefore important targets for structural analysis. Based on the MD population analysis and NMR, the major conformers of each mannobiose were identified and used as input for DFT analysis. By systematically varying the solvent models used to describe water interacting with the molecules and applying overlap integral analysis to the resulting calculational ROA spectra, we found that a full quantum mechanical/molecular mechanical approach is required for an optimal calculation of the ROA parameters. Subsequent normal mode analysis of the predicted vibrational modes was attempted in order to identify possible marker bands for glycosidic linkages. However, the normal mode vibrations of the mannobioses are completely delocalised, presumably due to conformational flexibility in these compounds, rendering the identification of isolated marker bands unfeasible

Warming, but Not Acidification, Restructures Epibacterial Communities of the Baltic Macroalga Fucus vesiculosus With Seasonal Variability

Due to ocean acidification and global warming, surface seawater of the western Baltic Sea is expected to reach an average of ∼1100 μatm pCO2 and an increase of ∼5°C by the year 2100. In four consecutive experiments (spanning 10–11 weeks each) in all seasons within 1 year, the abiotic factors temperature (+5°C above in situ) and pCO2 (adjusted to ∼1100 μatm) were tested for their single and combined effects on epibacterial communities of the brown macroalga Fucus vesiculosus and on bacteria present in the surrounding seawater. The experiments were set up in three biological replicates using the Kiel Outdoor Benthocosm facility (Kiel, Germany). Phylogenetic analyses of the respective microbiota were performed by bacterial 16S (V1-V2) rDNA Illumina MiSeq amplicon sequencing after 0, 4, 8, and 10/11 weeks per season. The results demonstrate (I) that the bacterial community composition varied in time and (II) that relationships between operational taxonomic units (OTUs) within an OTU association network were mainly governed by the habitat. (III) Neither single pCO2 nor pCO2:Temperature interaction effects were statistically significant. However, significant impact of ocean warming was detected varying among seasons. (IV) An indicator OTU (iOTU) analysis identified several iOTUs that were strongly influenced by temperature in spring, summer, and winter. In the warming treatments of these three seasons, we observed decreasing numbers of bacteria that are commonly associated with a healthy marine microbial community and—particularly during spring and summer—an increase in potentially pathogenic and bacteria related to intensified microfouling. This might lead to severe consequences for the F. vesiculosus holobiont finally affecting the marine ecosystem

Some General Regularities of Techno-Economic Evolution

One of the most exciting phenomena of the modern world is the fundamentally homogeneous direction of the overall techno-economic development trajectory in practically all regions of the world. The existing economic systems in different countries are collapsing one after another under the pressure of an expanding industrial culture and are becoming drawn into the international division of labor. Simultaneously, their economic development is influenced by the general regularities of the world techno-economic system, the rhythm of which is set by the industrially developed countries. These general regularities of long-term techno-economic development, invariant under different sociopolitical systems, are the subject of this chapter

Structure and giant magnetoresistance of granular Co-Cu nanolayers prepared by cross-beam PLD

A series of Co_xCu_{100-x} (x = 0, 40...75, 100) layers with thicknesses in-between 13 nm and 55 nm were prepared on silicon substrates using cross-beam pulsed laser deposition. Wide-angle X-ray diffraction (WAXRD), transmission electron microscopy (TEM) and electrical transport measurements revealed a structure consisting of decomposed cobalt and copper grains with grain sizes of about 10 nm. The influence of cobalt content and layer thickness on the grain size is discussed. Electron diffraction (ED) indicates the presence of an intermetallic Co-Cu phase of Cu3Au structure-type. Thermal treatment at temperatures between 525 K and 750 K results in the progressive decomposition of Co and Cu, with an increase of the grain sizes up to about 100 nm. This is tunable by controlling the temperature and duration of the anneal, and is directly observable in WAXRD patterns and TEM images. A careful analysis of grain size and the coherence length of the radiation used allows for an accurate interpretation of the X-ray diffraction patterns, by taking into account coherent and non-coherent scattering. The alloy films show a giant magnetoresistance of 1...2.3 % with the maximum obtained after annealing at around 725 K.Comment: 9 pages, 9 figure