The formation of Kuiper-belt Binaries through Exchange Reactions

Recent observations have revealed an unexpectedly high binary fraction among the Trans-Neptunian Objects (TNOs) that populate the Kuiper-belt. The discovered binaries have four characteristics they comprise a few percent of the TNOs, the mass ratio of their components is close to unity, their internal orbits are highly eccentric, and the orbits are more than 100 times wider than the primary's radius. In contrast, theories of binary asteroid formation tend to produce close, circular binaries. Therefore, a new approach is required to explain the unique characteristics of the TNO binaries. Two models have been proposed. Both, however, require extreme assumptions on the size distribution of TNOs. Here we show a mechanism which is guaranteed to produces binaries of the required type during the early TNO growth phase, based on only one plausible assumption, namely that initially TNOs were formed through gravitational instabilities of the protoplanetary dust layer.Comment: 12pages, 4 figure

Engaging with community researchers for exposure science: lessons learned from a pesticide biomonitoring study

A major challenge in biomonitoring studies with members of the general public is ensuring their continued involvement throughout the necessary length of the research. The paper presents evidence on the use of community researchers, recruited from local study areas, as a mechanism for ensuring effective recruitment and retention of farmer and resident participants for a pesticides biomonitoring study. The evidence presented suggests that community researchers' abilities to build and sustain trusting relationships with participants enhanced the rigour of the study as a result of their on-the-ground responsiveness and flexibility resulting in data collection beyond targets expected

Influences of club connectedness among young adults in Western Australian community-based sports clubs

Background: Along with physical benefits, community-based sport provides opportunities to enhance connectedness, an important protective factor of social and emotional health. However, young Australians participating in sport have been found to drink alcohol at higher levels than their non-sporting peers, and many clubs serve unhealthy food and beverages. This study explored the association between the dependent variable, level of alcohol consumption (AUDIT-C) and connectedness to club and other health behaviours among young people aged 18-30 years who play club sport in Western Australia. Methods: An online cross sectional survey measured levels of alcohol consumption (AUDIT-C), alcohol-related harm, connectedness (including volunteering and team cohesion), mental wellbeing, healthy food options and club sponsorship among young adults aged 18-30 years involved in sports clubs in Western Australia (n = 242). Relationships and association between the dependent variable (AUDIT-C) and independent variables were assessed. Results: Male sportspeople were more likely to drink alcohol at high-risk levels than females (p <.001), and respondents belonging to a club that received alcohol-related sponsorship were more likely to drink at high-risk levels (p =.019). Females were significantly more likely to want healthy food and beverage options provided at their clubs (p = 0.011). When all factors were considered team cohesion (p = 0.02), alcohol expectations (p = <.001), occurrences of experienced alcohol-related harm (p = <.001) and length of club membership (p = 0.18) were significant predictors of high-risk AUDIT-C (R 2 =.34, adjusted R 2 =.33, F (4, 156) = 20.43, p = <.001). High-risk AUDIT-C and club connectedness predicted strong team cohesion (R 2 =.39, adjusted R 2 =.39, F (2, 166) = 53.74, p = <.001). Conclusions: Findings from this study may inform policy and practice to enhance healthy behaviours among young adults participating in community sports clubs in Australia and other countries

What's wrong with John? A randomised controlled trial of Mental Health First Aid (MHFA) training with nursing students

BACKGROUND: The prevalence of mental health problems have been found to be higher among university students compared to their non-student peers. Nursing students in particular face a range of additional stressors which may impact their undergraduate performance and their careers. Mental Health First Aid (MHFA) aims to increase mental health literacy and to reduce stigma and may positively impact on the student population. This paper describes a MHFA randomised controlled trial targeting nursing students at a large Australian university. This study aimed to measure the impact of the MHFA course on mental health literacy, mental health first aid intentions, confidence in helping someone with a mental health problem and stigmatising attitudes including social distance. METHODS: Participants were first year nursing students (n = 181) randomly allocated to the intervention (n = 92) or control (n = 89) group. Intervention group participants received the standardised MHFA course for nursing students. Online self-report questionnaires were completed at three time intervals: baseline (one week prior to the intervention: T1) (n = 140), post intervention (T2) (n = 120), and two months post intervention (T3) (n = 109). Measures included demographics, mental health knowledge, recognition of depression, confidence in helping, mental health first aid intentions and stigmatising attitudes including social distance. Repeated measures ANOVA was computed to measure if the impact of time (T1, T2, T3) and group (intervention and control) on the outcome variables. RESULTS: There was a significant improvement among intervention compared to control group participants across the three time periods for knowledge scores (p &lt; 0.001), confidence in helping (p &lt; 0.001), mental health first aid intentions (p &lt; 0.001), total personal stigma (p &lt; 0.05), personal dangerous/unpredictable stigma (p &lt; 0.05) and social distance (p &lt; 0.05) scores. CONCLUSION: MHFA is useful training to embed in university courses and has the potential to enhance mental health literacy and reduce stigmatising attitudes and social distance. While this course has particular salience for nursing and other health science students, there are broader benefits to the general university population that should be considered and opportunities accordingly explored for all students to complete the course. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12614000861651 . Retrospectively registered 11 August 2014

Constraining dust and color variations of high-z SNe using NICMOS on Hubble Space Telescope

We present data from the Supernova Cosmology Project for five high redshift Type Ia supernovae (SNe Ia) that were obtained using the NICMOS infrared camera on the Hubble Space Telescope. We add two SNe from this sample to a rest-frame I-band Hubble diagram, doubling the number of high redshift supernovae on this diagram. This I-band Hubble diagram is consistent with a flat universe (Omega_Matter, Omega_Lambda= 0.29, 0.71). A homogeneous distribution of large grain dust in the intergalactic medium (replenishing dust) is incompatible with the data and is excluded at the 5 sigma confidence level, if the SN host galaxy reddening is corrected assuming R_V=1.75. We use both optical and infrared observations to compare photometric properties of distant SNe Ia with those of nearby objects. We find generally good agreement with the expected color evolution for all SNe except the highest redshift SN in our sample (SN 1997ek at z=0.863) which shows a peculiar color behavior. We also present spectra obtained from ground based telescopes for type identification and determination of redshift.Comment: 30 pages, 10 figures; accepted for publication in ApJ; v2: revised to match the version in the journa

Fast polarization mechanisms in the uniaxial tungsten-bronze relaxor strontium barium niobate SBN-81

The high-frequency dielectric response of the uniaxial strontium barium niobate crystals with 81% of Sr has been studied from 1 kHz to 30 THz along the polar c axis by means of several techniques (far infrared, time domain terahertz, high-frequency and low-frequency dielectric spectroscopies) in a wide temperature interval 20–600 K. Relaxor properties were observed in the complex dielectric response and four main excitations were ascertained below the phonon frequencies. These fast polarization mechanisms take place at THz, GHz and MHz ranges and show different temperature evolution. The central mode excitation in the THz range, related to anharmonic dynamics of cations, slightly softens from high temperatures and then hardens below T ~ 400 K. Below the phase transition (at T ~ 330 K) an additional microwave excitation appears near 10 GHz related to micro domain wall oscillations. The strongest relaxation appears in the GHz range and slows down on cooling according to the Arrhenius law. Finally, another relaxation, present in the MHz range at high temperatures, also slows down on cooling at least to the kHz range. These two relaxations are due to polar fluctuations and nanodomains dynamics. Altogether, the four excitations explain the dielectric permittivity maximum in the kHz range

Treatment of Aspergillus fumigatus in Patients with Cystic Fibrosis: A Randomized, Placebo-Controlled Pilot Study

Many patients with cystic fibrosis develop persistent airway infection/colonization with Aspergillus fumigatus, however the impact of A. fumigatus on clinical outcomes remains unclear. The objective of this study was to determine whether treatment directed against Aspergillus fumigatus improves pulmonary function and clinical outcomes in patients with cystic fibrosis (CF).We performed a double-blind randomized placebo-controlled pilot clinical trial involving 35 patients with CF whose sputum cultures were chronically positive for A. fumigatus. Participants were centrally randomized to receive either oral itraconazole 5 mg/kg/d (N = 18) or placebo (N = 17) for 24 weeks. The primary outcome was the proportion of patients who experienced a respiratory exacerbation requiring intravenous antibiotics over the 24 week treatment period. Secondary outcomes included changes in FEV(1) and quality of life.Over the 24 week treatment period, 4 of 18 (22%) patients randomized to itraconazole experienced a respiratory exacerbation requiring intravenous antibiotics, compared to 5 of 16 (31%) placebo treated patients, P = 0.70. FEV(1) declined by 4.62% over 24 weeks in the patients randomized to itraconazole, compared to a 0.32% improvement in the placebo group (between group difference = -4.94%, 95% CI: -15.33 to 5.45, P = 0.34). Quality of life did not differ between the 2 treatment groups throughout the study. Therapeutic itraconazole blood levels were not achieved in 43% of patients randomized to itraconazole.We did not identify clinical benefit from itraconazole treatment for CF patients whose sputum was chronically colonized with A. fumigatus. Limitations of this pilot study were its small sample size, and failure to achieve therapeutic levels of itraconazole in many patients.ClinicalTrials.gov NCT00528190

How does social integration influence breast cancer control among urban African-American women? Results from a cross-sectional survey

<p>Abstract</p> <p>Background</p> <p>Although social integration is a well-established influence on health, less is known about how the specific types of social connection (social roles, social networks, and social support) influence knowledge, attitudes, and practices for specific prevention goals, and how to utilize these influences in interventions with priority populations. This research examined the prevalence of social roles, networks and support among 576 urban African-American women age 45–93 in East Baltimore, Maryland, and the association of these social factors with breast cancer related knowledge, attitudes, and practices.</p> <p>Methods</p> <p>Using data from 1997–1998 in-home interviews, we developed indices of six possible social roles, social networks of family, neighborhood and church, and instrumental and emotional social support. In multivariate models adjusting for age, education, and medical care, we examined the association of each social influence on breast cancer knowledge, attitudes, screening recency and intention, and treatment preferences.</p> <p>Results</p> <p>We found substantial variation in social integration among these women, with social integration positively associated with overall health and well-being. Social roles and networks were positively associated with screening knowledge, and emotional support and church networks were positively associated with attitudes conducive to early detection and treatment. In regard to screening behaviors, family networks were associated with both screening recency and intention. Women with greater church networks and emotional support held more conservative attitudes towards lumpectomy, reconstruction, and clinical trials.</p> <p>Conclusion</p> <p>Overall, social integration is a positive influence on breast cancer control and should be utilized where possible in interventions, including identifying surrogate mechanisms for support for subgroups without existing social resources.</p

Longer postpartum hospitalization options – who stays, who leaves, what changes?

BACKGROUND: This paper examines the practice implications of a policy initiative, namely, offering women in Ontario Canada up to a 60-hour postpartum in-hospital stay following an uncomplicated vaginal delivery. This change was initiated out of concern for the effects of 'early' discharge on the health of mothers and their infants. We examined who was offered and who accepted extended stays, to determine what factors were associated with the offer and acceptance of this option, and the impact that these decisions had on post-discharge health status and service utilization of mothers and infants. METHODS: The data reported here came from two related studies of health outcomes and service utilization of mothers and infants. Data were collected from newly delivered mothers who had uncomplicated vaginal deliveries. Questionnaires prior to discharge and structured telephone interviews at 4-weeks post discharge were used to collect data before and after policy implementation. Qualitative data were collected using focus groups with hospital and community-based health care managers and providers at each site. For both studies, samples were drawn from the same five purposefully selected hospitals. Further analysis compared postpartum health outcomes and post discharge service utilization of women and infants before and after the practice change. RESULTS: Average length of stay (LOS) increased marginally. There was a significant reduction in stays of <24 hours. The offer of up to a 60-hour LOS was dependent upon the hospital site, having a family physician, and maternal ethnicity. Acceptance of a 60-hour LOS was more likely if the baby had a post-delivery medical problem, it was the woman's first live birth, the mother identified two or more unmet learning needs in hospital, or the mother was unsure about her own readiness for discharge. Mother and infant health status in the first 4 weeks after discharge were unchanged following introduction of the extended stay option. Infant service use also was unchanged but rate of maternal readmission to hospital increased and mothers' use of community physicians and emergency rooms decreased. CONCLUSION: This research demonstrates that this policy change was selectively implemented depending upon both institutional and maternal factors. LOS marginally increased overall with a significant decrease in <24-hour stays. Neither health outcomes nor service utilization changed for infants. Women's health outcomes remained unchanged but service utilization patterns changed

Murine Dendritic Cells Transcriptional Modulation upon Paracoccidioides brasiliensis Infection

Limited information is available regarding the modulation of genes involved in the innate host response to Paracoccidioides brasiliensis, the etiologic agent of paracoccidioidomycosis. Therefore, we sought to characterize, for the first time, the transcriptional profile of murine bone marrow-derived dendritic cells (DCs) at an early stage following their initial interaction with P. brasiliensis. DCs connect innate and adaptive immunity by recognizing invading pathogens and determining the type of effector T-cell that mediates an immune response. Gene expression profiles were analyzed using microarray and validated using real-time RT-PCR and protein secretion studies. A total of 299 genes were differentially expressed, many of which are involved in immunity, signal transduction, transcription and apoptosis. Genes encoding the cytokines IL-12 and TNF-α, along with the chemokines CCL22, CCL27 and CXCL10, were up-regulated, suggesting that P. brasiliensis induces a potent proinflammatory response in DCs. In contrast, pattern recognition receptor (PRR)-encoding genes, particularly those related to Toll-like receptors, were down-regulated or unchanged. This result prompted us to evaluate the expression profiles of dectin-1 and mannose receptor, two other important fungal PRRs that were not included in the microarray target cDNA sequences. Unlike the mannose receptor, the dectin-1 receptor gene was significantly induced, suggesting that this β-glucan receptor participates in the recognition of P. brasiliensis. We also used a receptor inhibition assay to evaluate the roles of these receptors in coordinating the expression of several immune-related genes in DCs upon fungal exposure. Altogether, our results provide an initial characterization of early host responses to P. brasiliensis and a basis for better understanding the infectious process of this important neglected pathogen