The state of methamphetamine ('tik') use among youth in the Western Cape, South Africa

BACKGROUND Methamphetamine use among youth in the Western Cape Province of South Africa has increased at alarming rates over the past decade. Although current estimates of youth use exist, they range from 2% to 12%. OBJECTIVES To identify (i) the prevalence of methamphetamine use in Western Cape youth and (ii) the association between use and known risk factors for methamphetamine use. METHODS Data were obtained from 10 000 Western Cape Province Grade 8 learners in 54 secondary schools (mean age 14.0 years). Prevalence was descriptively reported while risk factors for past-month use were modelled in a hierarchical logistic regression with demographic, socioeconomic status, substance use, sexual activity and relationship predictors. RESULTS Approximately 5% (n=496) of learners had used methamphetamine within their lifetime. Of these users, 65% (n=322) had used in the past month or week. Compared to never users, past-month users were more likely to be male, less likely to have a present or partially present mother, less likely to live in an apartment/flat/brick house, more likely to have used alcohol and tobacco and more likely to report having a same-sex partner. CONCLUSION Results replicate previously known methamphetamine risk factors and highlight the need to address methamphetamine use in comprehensive prevention initiatives.DHE

Perceived parental control, restructuring ability, and leisure motivation: A cross-cultural comparison

Leisure is viewedworldwide as an important developmental context for adolescents. As leisure research and programs are shared across nations, it is crucial to examine the cultural equivalence of leisure-related constructs and how they are related. Grounded in self-determination theory, this study explored the influence of perceived parental control and leisure restructuring ability on leisure motivation (amotivation and autonomous motivation) using samples of eighth grade adolescents in the United States and South Africa. Results of multiple-group structural equation modeling showed that the measurement model of the constructs was equivalent across the two samples, but the determinants of leisure motivation differed between the two samples. The findings provide implications for future cross-cultural research in leisure and offer insights on design and adaptation of leisure-based intervention and education programs in different cultural contexts.IS

Suppression of p53 function in normal human mammary epithelial cells increases sensitivity to extracellular matrix–induced apoptosis

Little is known about the fate of normal human mammary epithelial cells (HMECs) that lose p53 function in the context of extracellular matrix (ECM)–derived growth and polarity signals. Retrovirally mediated expression of human papillomavirus type 16 (HPV-16) E6 and antisense oligodeoxynucleotides (ODNs) were used to suppress p53 function in HMECs as a model of early breast cancer. p53+ HMEC vector controls grew exponentially in reconstituted ECM (rECM) until day 6 and then underwent growth arrest on day 7. Ultrastructural examination of day 7 vector controls revealed acinus-like structures characteristic of normal mammary epithelium. In contrast, early passage p53− HMEC cells proliferated in rECM until day 6 but then underwent apoptosis on day 7. p53− HMEC-E6 passaged in non-rECM culture rapidly (8–10 passages), lost sensitivity to both rECM-induced growth arrest and polarity, and also developed resistance to rECM-induced apoptosis. Resistance was associated with altered expression of α3-integrin. Treatment of early passage p53− HMEC-E6 cells with either α3- or β1-integrin function-blocking antibodies inhibited rECM-mediated growth arrest and induction of apoptosis. Our results indicate that suppression of p53 expression in HMECs by HPV-16 E6 and ODNs may sensitize cells to rECM-induced apoptosis and suggest a role for the α3/β1-heterodimer in mediating apoptosis in HMECs grown in contact with rECM

With a little help from my friends? A longitudinal look at the role of peers versus friends on adolescent alcohol use

Introduction: Alcohol is the most commonly used substance by South African adolescents. Social norms play a key role in alcohol use, although distinctions are not always made between descriptive and injunctive norms and peer proximity. Additionally, little research identifies factors attenuating social norms, peer proximity, and alcohol use, such as one's ability to resist peer influence. Methods: The current study investigates the relationship between adolescent alcohol use in 9th Grade and descriptive peer and injunctive friend norms in 8th grade, the moderating role of resistance to peer influence, and sex differences. Data were from South African students (N=3592; Mage=14) participating in the HealthWise South Africa implementation quality trial. Results: Path model results indicated injunctive friend norms, but not peer norms, influenced alcohol use. Resistance to peer influence did not moderate relationships and group comparisons found no sex differences. Conclusion: Findings suggest social proximity shapes influences of alcohol use. Despite a differing cultural context, findings were consistent with those from the United States, indicating social proximity is relevant cross-culturally

Profiles of adolescent leisure motivation and substance use in the HealthWise South Africa research trial: a person-centered approach

Engaging in intrinsically motivated behaviors, both within and outside of the leisure context, is associated with well-being. However, individuals can be driven by multiple types of motivation simultaneously, and the impact of constellations of leisure motivation is relatively unknown. The current study uses South African adolescents in the HealthWise South Africa efficacy trial (N¼2,204; Mage¼14.0) to identify profiles of leisure motivation, examine the association between profiles and substance use, and evaluate the impact of HealthWise on changes in motivation profiles over time. Results indicate three distinct profiles: high consistent motivation, low consistent motivation, and high intrinsic motivation. Members of the high intrinsic profile had the lowest odds of substance use. Profiles were fairly stable across all time points except for females in a high-training intervention school. Results illustrate the importance of identifying and understanding typologies of leisure motivation and health across time, which can be used to promote positive development in adolescents

Testing the Cosmic Coincidence Problem and the Nature of Dark Energy

Dark energy models which alter the relative scaling behavior of dark energy and matter could provide a natural solution to the cosmic coincidence problem - why the densities of dark energy and dark matter are comparable today. A generalized class of dark energy models is introduced which allows non-canonical scaling of the ratio of dark matter and dark energy with the Robertson-Walker scale factor a(t). Upcoming observations, such as a high redshift supernova survey, application of the Alcock-Paczynski test to quasar pairs, and cluster evolution, will strongly constrain the relative scaling of dark matter and dark energy as well as the equation of state of the dark energy. Thus, whether there actually is a coincidence problem, and the extent of cosmic coincidence in the universe's recent past can be answered observationally in the near future. Determining whether today is a special time in the history of the universe will be a SNAP.Comment: 5 pages, 3 figures, revtex4, submitted to PR

Tied to the worldly work of writing: parent as ethnographer

Parent narratives have contributed to ethnographic accounts of the lives of autistic children (Kelly, 2005) but there are fewer examples of parents producing their own autoethnographies. This paper explores the affordances of an online blog for enabling a parent of an autistic child to produce a written record of practice which may be considered 'autoethnographic'. Richardson’s (2005) framework for ethnography as Creative Analytic Process is applied to extracts from a blog post in order to consider its contribution; reflexivity; aesthetic merit; and impact. The paper addresses the methodological and ethical implications of reconceptualising parents as researchers and the potential contribution of new writing platforms to the development of auto/ethnography. Key words: Autism, Auto/ethnography, Blog, Disability, Mothe

TZM-gfp cells: a tractable fluorescent tool for analysis of rare and early HIV-1 infection

Here we describe TZM-gfp, a novel HIV-1 reporter cell derived from the same parental clone JC.53, used previously to generate the widely-utilized indicator cell line TZM-bl. We re-engineered JC.53 cells to express GFP under regulation of HIV Tat and Rev. We characterize the new reporter cell line to show that TZM-gfp cells are equally susceptible to HIV infection, exhibit minimal background signal, and can report HIV infection in rare cells from a bulk population of experimentally-infected human monocyte-derived macrophages. We demonstrate the utility and sensitivity of the cells in detection of even a single HIV-positive macrophage by fluorescence-assisted correlative electron microscopy, using the GFP signal to guide imaging of HIV virions in primary co-culture. Finally, we used TZM-gfp cells for viral capture during co-culture with human peripheral blood mononuclear cells, showing that TZM-gfp can support outgrowth and analyses of patient-derived primary HIV-1 isolates

Space Based Gravitational Wave Astronomy Beyond LISA

The Laser Interferometer Space Antenna (LISA) will open three decades of gravitational wave(GW) spectrum between 0.1 and 100 mHz, the mHz band [1]. This band is expected to be the richest part of the GW spectrum, in types of sources, numbers of sources, signal-to-noise ratios and discovery potential. When LISA opens the low-frequency window of the gravitational wave spectrum,around 2034, the surge of gravitational-wave astronomy will strongly compel a subsequent mission to further explore the frequency bands of the GW spectrum that can only be accessed from space. The 2020's is the time to start developing technology and studying mission concepts for a large-scale mission to be launched in the 2040's. The mission concept would then be proposed to Astro2030. Only space-based missions can access the GW spectrum between 108 and 1 Hz because of the Earth's seismic noise. This white paper surveys the science in this band and mission concepts that could accomplish that science. The proposed small scale activity is a technology development program that would support a range of concepts and a mission concept study to choose a specific mission concept for Astro2030. In this white paper, we will refer to a generic GW mission beyond LISA as bLISA