The Nature and Role of Physical Models in Enhancing Sixth Grade Students\u27 Mental Models of Groundwater and Groundwater Processes

Through a non-experimental descriptive and comparative mixed-methods approach, this study investigated the experiences of sixth grade earth science students with groundwater physical models through an extended SE learning cycle format. The data collection was based on a series of quantitative and qualitative research tools intended to investigate students\u27 ideas and changes in ideas rather than measure their achievement. The measures included a groundwater survey, classroom observations, and one-on-one follow-up student interviews for triangulation of data sources. The research was carried out at a K-12 independent school in eastern Virginia using two classes of sixth grade earth science students (n=30). The findings suggest that physical models help students identify the components porosity and permeability with respect to water flow in groundwater systems. Higher levels of system thinking were best demonstrated in model components that allowed students to experience groundwater pollution activities and pumping groundwater wells. However, the results also indicated that due to model constraints, students can develop misconceptions during the use of physical models, specifically more complex physical models as in the Groundwater Exploration Activity Model. A pure discovery learning format while using physical models without guidance or formative assessment probes can lead to misconceptions about groundwater processes as well as confusion between model attributes and real world groundwater systems. The implications of this study relate directly to the inclusion of groundwater in the new national science standards released in 2011; A Framework for K-12 Science Standard; Practices, Crosscutting Concepts, and Core Ideas (NRC, 2011). The new national standards, as in other educational reform efforts, will have the ability to affect curricular and instructional strategies in science education. From the results of this study, it was concluded that best practices for using groundwater physical models in groundwater instruction should be through an inquiry based approach such as a 5E learning cycle, that includes both teacher guidance and feedback during model activities and incorporates an Express phase with extensive formative assessment probes for student reflection of their learning process

The Y-Band at 1.035 um: Photometric Calibration and the Dwarf Stellar/Sub-Stellar Color Sequence

We define and characterize a photometric bandpass (called "Y") that is centered at 1.035 um, in between the traditionally classified ``optical'' and ``infrared'' spectral regimes. We present Y magnitudes and Y-H and Y-K colors for a sample consisting mostly of photometric and spectral standards, spanning the spectral type range sdO to T5V. Deep molecular absorption features in the near-infrared spectra of extremely cool objects are such that the Y-H and Y-K colors grow rapidly with advancing spectral type especially from late M through mid L, substantially more rapidly than J-H or H-K which span a smaller total dynamic range. Consistent with other near-infrared colors, however, Y-H and Y-K colors turn blueward in the L6-L8 temperature range with later T-type objects having colors similar to those of warmer M and L stars. Use of the Y-band filter is nonetheless promising for easy identification of low-mass stars and brown dwarfs, especially at young ages. The slope of the interstellar reddening vector within this filter is A_Y = 0.38 x A_V. Reddening moves stars nearly along the YHK dwarf color sequence making it more difficult to distinguish unambiguously very low mass candidate brown dwarf objects from higher mass stars seen, e.g. through the galactic plane or towards star-forming regions. Other diagrams involving the Y-band may be somewhat more discriminating.Comment: accepted at PAS

Composition of objectively measured physical activity and sedentary behaviour participation across the school-day, influence of gender and weight status: cross-sectional analyses among disadvantaged Victorian school children

BACKGROUND: The after-school period has been described as the \u27critical window\u27 for physical activity (PA) participation. However, little is known about the importance of this window compared with the before and during-school period among socioeconomically disadvantaged children, and influence of gender and weight status. METHODS: 39 out of 156 (RR=25%) invited primary schools across 26 local government areas in Victoria, Australia, consented to participate with 856 children (RR=36%) participating in the wider study. The analysis sample included 298 Grade 4 and Grade 6 children (mean age: 11.2±1.1; 44% male) whom met minimum accelerometry wear-time criteria and had complete height, weight and health-behaviours questionnaire data. Accelerometry measured duration in daily light-intensity PA (LPA), moderate-to-vigorous PA (MVPA) and sedentary time (ST) was calculated for before-school=8-8:59, during-school=9:00-15:29 and after-school=15:30-18:00. Bivariate and multivariable linear regression analyses were conducted. RESULTS: During-school represented the greatest accumulation of LPA and MVPA compared with the before and after-school periods. Boys engaged in 102 min/day of LPA (95% CI 98.5 to 104.9) and 62 min/day of MVPA (95% CI 58.9 to 64.7) during-school; girls engaged in 103 min/day of LPA (95% CI 99.7 to 106.5) and 45 min/day of MVPA (95% CI 42.9 to 47.4). Linear regression models indicated that girls with overweight or obesity engaged in significantly less LPA, MVPA and more time in ST during-school. CONCLUSIONS: This study highlights the importance of in-school PA compared with after-school PA among socioeconomically disadvantage children whom may have fewer resources to participate in after-school PA

The Influence of Affect on HPV Vaccine Decision Making in an HPV Vaccine Naïve College Student Population

The HPV vaccine is recommended for all adolescents starting at age 11, but coverage is low, especially in the young adult population. The CDC is prioritizing catch-up vaccination and has expanded recommendations for all young adults to age 26. College students may be ideal targets for HPV vaccine interventions as they typically have on-site clinics that offer prevention services and students are in the position to make decisions about their own healthcare. We examined the risk perceptions of 101 HPV vaccine-naïve college students, both in terms of risk cognition (beliefs about susceptibility to HPV-related cancers and genital warts) and affect (worry and fear regarding HPV-related health outcomes) as they relate to HPV vaccine intentions. Participants completed an online survey, reporting absolute and comparative risk perceptions for HPV-related cancers/genital warts, fear and worry related to getting HPV-related cancer and/or genital warts, desire for positive emotions, affective associations with the HPV vaccine, and intentions to get the HPV vaccine. More fear/worry about vaccination was directly associated with increased vaccine intentions. The perceived risk to intentions relation included an indirect effect via fear/worry. Desire for positive affect strengthened this relation. Positive affective associations with the HPV vaccine were also related to increased vaccine intentions. Given the public health impact of increasing HPV vaccine coverage for young adults, educational strategies framing the HPV vaccine positively while decreasing fear/worry related to negative health outcomes might increase interest in on-campus catch-up vaccination

Gardnerella vaginalis promotes group B Streptococcus vaginal colonization, enabling ascending uteroplacental infection in pregnant mice

BACKGROUND: Group B Streptococcus is a common vaginal bacterium and the leading cause of invasive fetoplacental infections. Group B Streptococcus in the vagina can invade through the cervix to cause ascending uteroplacental infections or can be transmitted to the neonate during vaginal delivery. Some studies have found that women with a dysbiotic polymicrobial or Lactobacillus-depleted vaginal microbiota are more likely to harbor group B Streptococcus. Gardnerella vaginalis is often the most abundant bacteria in the vaginas of women with dysbiosis, while being detected at lower levels in most other women, and has been linked with several adverse pregnancy outcomes. Mouse models of group B Streptococcus and Gardnerella vaginalis colonization have been reported but, to the best of our knowledge, the two have not been studied together. The overarching idea driving this study is that certain members of the dysbiotic vaginal microbiota, such as Gardnerella vaginalis, may directly contribute to the increased rate of group B Streptococcus vaginal colonization observed in women with vaginal dysbiosis. OBJECTIVE: We used a mouse model to test the hypothesis that vaginal exposure to Gardnerella vaginalis may facilitate colonization and/or invasive infection of the upper reproductive tract by group B Streptococcus during pregnancy. STUDY DESIGN: Timed-pregnant mice were generated using an allogeneic mating strategy with BALB/c males and C57Bl/6 females. Dams were vaginally inoculated at gestational day 14 with group B Streptococcus alone (using a 10-fold lower dose than previously reported models) or coinoculated with group B Streptococcus and Gardnerella vaginalis. Bacterial titers were enumerated in vaginal, uterine horn, and placental tissues at gestational day 17. The presence (Fisher exact tests) and levels (Mann-Whitney U tests) of bacterial titers were compared between mono- and coinoculated dams in each compartment. Relative risks were calculated for outcomes that occurred in both groups. Tissue samples were also examined for evidence of pathophysiology. RESULTS: Inoculation of pregnant mice with 10 CONCLUSION: These data suggest that Gardnerella vaginalis vaginal exposure can promote group B Streptococcus vaginal colonization, resulting in a greater likelihood of invasive perinatal group B Streptococcus infections. These findings suggest that future clinical studies should examine whether the presence of Gardnerella vaginalis is a risk factor for group B Streptococcus vaginal colonization in women. Because Gardnerella vaginalis can also be present in women without bacterial vaginosis, these findings may be relevant both inside and outside of the context of vaginal dysbiosis

Factors associated with physical activity referral uptake and participation

The aim of this study was to examine participant and scheme characteristics in relation to access, uptake, and participation in a physical activity referral scheme (PARS) using a prospective population-based longitudinal design. Participants (n = 3762) were recruited over a 3-year period. Logistic regression analyses identified the factors associated with the outcomes of referral uptake, participation, and completion (>= 80% attendance). Participant's age, sex, referral reason, referring health professional, and type of leisure provider were the independent variables. Based on binary logistic regression analysis (n=2631), only primary referral reason was associated with the PARS coordinator making contact with the participants. In addition to the influence of referral reason, females were also more likely (odds ratio 1.250, 95% confidence interval 1.003-1.559, P = 0.047) to agree to be assigned to a leisure provider. Referral reason and referring health professional were associated with taking up a referral opportunity. Older participants (1.016, 1.010-1.023, P = 0.001) and males were more likely to complete the referral. In conclusion, the PARS format may be less appropriate for those more constrained by time (women, young adults) and those with certain referral reasons (overweight/obesity, mental health conditions). More appropriate targeting at the point of referral could improve participation rates by revealing or addressing barriers that might later result in dropout

Low-dose inoculation of Escherichia coli achieves robust vaginal colonization and results in ascending infection accompanied by severe uterine inflammation in mice

Escherichia coli infection of the female reproductive tract is a significant cause of disease in humans and animals, but simple animal models are lacking. Here we report that vaginal inoculation of uropathogenic E. coli strains UTI89 and CFT073 in non-pregnant, estrogen-treated mice resulted in robust colonization of the vagina and uterine horns, whereas titers of the lab strain MG1655 were significantly lower. Non-estrogenized mice also became colonized, but there was more variation in titers. A dose of 104 colony-forming units (CFU) UTI89 was sufficient to result in colonization in all estrogenized mice, and we also observed bacterial transfer between inoculated and uninoculated estrogenized cage mates. UTI89 infection led to inflammation and leukocyte infiltration into the uterine horns as evidenced by tissue histology. Flow cytometry experiments revealed that neutrophil, monocyte and eosinophil populations were significantly increased in infected uterine horns. This model is a simple way to study host-pathogen interactions in E. coli vaginal colonization and uterine infection. There are immediate implications for investigators studying urinary tract infection using mouse models, as few E. coli are required to achieve reproductive colonization, resulting in an additional, underappreciated mucosal reservoir