Impact of parasite sympatry on the geographic mosaic of coevolution

Slave-making ants are specialized social parasites that steal the young from colonies of their host species to augment their slave supply. The degree of parasite–host specialization has been shown to shape the trajectory along which parasites and hosts coevolve and is a prime contributor to the geographic mosaic of coevolution. However, virtually nothing is known about extrinsic influences on parasite–host dynamics, although the simple addition of a competing slave-maker may significantly alter selection pressures. Here we report the effect of two sympatric slave-makers on a single host. We measured temporal and spatial changes in colonies of the primary host Temnothorax curvispinosus that had been placed in field enclosures along with a single colony of either one or both species of the North American slave-making ants Protomognathus americanus and Temnothorax duloticus. Each slave-maker species alone had a negative impact on its hosts, although one slave-maker species more frequently decimated its host assemblage and then went extinct. Nevertheless, the combined effect in mixed-parasite enclosures was, surprisingly, greatly attenuated. Virulent slave-maker growth and prudent slave-maker decay in these shared enclosures, together with field data showing an inverse proportional relationship between the two slave-makers in natural populations, suggest that their checkered distribution is a consequence of direct asymmetrical antagonism between parasites. Thus, our results imply a tripartite coevolutionary arms race, whereby intraguild interactions among social parasites strongly affect the realized selection pressures on hosts and contribute to the geographic mosaic of coevolution

Investigating the relationship between HIV testing and risk behaviour in Britain: National Survey of Sexual Attitudes and Lifestyles 2000.

OBJECTIVES: To estimate the prevalence of, and identify factors associated with, HIV testing in Britain. DESIGN: A large, stratified probability sample survey of sexual attitudes and lifestyles. METHODS: A total of 12,110 16-44 year olds completed a computer-assisted face-to-face interview and self-interview. Self-reports of HIV testing, i.e. the timing, reasons for and location of testing, were included. RESULTS: A total of 32.4% of men and 31.7% of women reported ever having had an HIV test, the majority of whom were tested through blood donation. When screening for blood donation and pregnancy were excluded, 9.0% of men and 4.6% of women had had a voluntary confidential HIV test (VCT) in the past 5 years. However, one third of injecting drug users and men who have sex with men had a VCT in the past 5 years. VCT in the past 5 years was significantly associated with age, residence, ethnicity, self-perceived HIV risk, reporting greater numbers of sexual partners, new sexual partners from abroad, previous sexually transmitted infection diagnosis, and injecting non-prescribed drugs for men and women, and same-sex partners (men only). Whereas sexually transmitted disease clinics were important sites for VCT, general practice accounted for almost a quarter of VCT. CONCLUSION: HIV testing is relatively common in Britain; however, it remains largely associated with population-based blood donation and antenatal screening programmes. In contrast, VCT remains highly associated with high-risk (sexual or drug-injecting) behaviours or population sub-groups at high risk. Strategies to reduce undiagnosed prevalent HIV infection will require further normalization and wider uptake of HIV testing

InSight Aerothermal Environment Assessment

The Mars Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) spacecraft, which successfully touched down on the planet surface on November 26, 2018, was proposed as a near build-to-print copy of the Mars Phoenix vehicle to reduce the overall cost and risk of the mission. Since the lander payload and the atmospheric entry trajectory were similar enough to those of the Phoenix mission, it was expected that the Phoenix thermal protection material thickness would be sufficient to withstand the entry heat load. However, allowances were made for increasing the heatshield thickness because the planned spacecraft arrival date coincided with the Mars dust storm season. The aftbody Thermal Protection System (TPS) components were not expected to change. In a first for a US Mars mission, the aerothermal environments for InSight included estimates of radiative heat flux to the aftbody from the wake. The combined convective and radiative heat fluxes were used to determine if the as-flown Phoenix thermal protection system (TPS) design would be sufficient for InSight. Although the radiative heat fluxes on the aftbody were predicted to be comparable to, or even higher than the local convective heat fluxes, all analyses of the aftbody TPS showed that the design would still be adequate. Aerothermal environments were computed for the vehicle from post-flight reconstruction of the atmosphere and trajectory and compared with the design environments. These comparisons showed that the predicted as-flown conditions were less severe than the design conditions

Exploring the impact of elevated depressive symptoms on the ability of a tailored asthma intervention to improve medication adherence among urban adolescents with asthma

BACKGROUND: In patients with asthma, medication adherence is a voluntary behavior that can be affected by numerous factors. Depression is an important co-morbidity in adolescents with asthma that may significantly impact their controller medication adherence and other asthma-related outcomes. The modifying effect of depressive symptoms on an asthma intervention’s ability to improve asthma controller medication adherence among urban adolescents with asthma has not yet been reported. OBJECTIVE: To assess self-reported symptoms of depression as an effect modifier of the relationship between randomization group and controller medication adherence at 6-month follow-up. METHODS: These analyses use data from a randomized controlled trial (RCT) conducted in Detroit high schools to evaluate a tailored asthma management program. The intervention included referrals to school or community resources for students reporting symptoms of depression and other issues. “Elevated depressive symptoms” was defined as a positive answer to ≥ 5 of 7 questions from a validated tool included on the baseline questionnaire. Self-reported adherence to controller medication was collected at intervention onset (session 1) and at 6-month follow up. Analyses were restricted to students with report of a controller medication at baseline. Logistic regression was used to assess elevated depressive symptoms as an effect modifier of the relationship between randomization group and 6-month adherence. RESULTS: Of the 422 students enrolled in the RCT, a controller medication was reported at intervention onset by n = 123 adolescents (29%). Analyzing this group, we observed an interaction between elevated depressive symptoms and adherence (p = 0.073). Stratified analysis showed better adherence in treatment group adolescents meeting criteria for elevated depressive symptoms at baseline as compared to the control group (adjusted Odds Ratio [aOR] = 9.50; p = 0.024). For adolescents without elevated depressive symptoms at baseline, differences in adherence by group assignment did not reach statistical significance (aOR 1.40, p = 0.49). CONCLUSIONS: In this sample of students reporting controller medications at baseline, report of elevated depressive symptoms at baseline and randomization to the intervention group was associated with significantly better adherence at 6-month follow up when compared to that of a control group. Larger studies are needed to evaluate the impact of depression on the relationship between adherence and asthma intervention effectiveness

Ozone profile observations in Houston, Texas (1994 - 2010) from aircraft, balloons, and satellites

Houston, Texas has long been an urban area plagued with high levels of surface ozone, particularly in spring and late summer. The combination of a large commuter population and one of the largest concentrations of petrochemical plants in the world results in abundant and nearly co-located sources of NOx and hydrocarbons. The location of Houston on the South Coast of the United States in a subtropical climate results in meteorological conditions that favor ozone production. Using MOZAIC (1994 - 2004), ozonesonde (2000, 2004 - 2010), and TES (2005 – 2010) data, we examine the evolution of ozone profiles over Houston during a period in which various strategies have been implemented to alleviate the ozone pollution problem. Using meteorological data from associated soundings and analyses, we identify and evaluate influences on the ozone profiles from natural and anthropogenic sources, as well as local and remote sources. We further investigate how these various influences have changed with time

A Web-Based Intervention is Feasible for Supporting Weight Loss and Increased Activity in Rural Women with Arthritis

Rural women have well documented health disparities, with higher prevalence of obesity and chronic conditions, including arthritis. Change in weight and actigraph-recorded data were examined in a subset of 63 of 82 women with physician-diagnosed arthritis who completed a 30-month web-based clinical trial. Repeated measures analyses showed women lost weight from baseline to six months, slowly regained at 18 and 30 months, ending with a lower weight than baseline F(1,62)=40.89, p\u3c0.001, η2p =0.40. Of 53 women with complete data, activity increased at six months, decreased at 18 months, and increased at 30 months F(1,52)=4.14, p =.04, η2p=0.07. Women showed improved change in weight and activity from baseline at six, 18 and 30 months. This study adds support that web-based programs may promote weight loss and activity in a hard-to-reach, underserved population of midlife and older rural women with arthriti

Contributions to anelasticity in langasite and langatate

Maximization of the quality factors Q of langasite (LGS) and langatate (LGT) is necessary for optimal performance of acoustic resonators of these materials in frequency-control and high-temperature sensing applications. In this report, measurements and least-squares analysis of Q(-1) as a function of ultrasonic frequency and temperature of undoped LGS (100 K to 750 K) and LGT (300 K to 760 K) reveal a superposition of physical effects, including point-defect relaxations and intrinsic phonon-phonon loss. In LGS, these effects are superimposed on a large temperature-dependent background with weak frequency dependence that is interpreted as arising from a relaxation process with a distribution of activation energies. This distributed relaxation is suggested to be a result of anelastic kink migration. No evidence for a significant background of this form is found in the LGT specimen, consistent with the lower measured dislocation etch-pit density of this crystal. The analysis of the dependence of Q(-1) of LGT on frequency and temperature indicates that, at near-ambient temperatures, the damping in this specimen is close to the intrinsic limit determined by phonon-phonon interactions. Piezoelectric/carrier relaxation, which must occur at sufficiently elevated temperatures, is found not to be a significant contribution to Q(-1), relative to defect-related contributions, in either LGS or LGT in the measured range of temperatures