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Developing a second, third, and fourth grade environmental unit on water education
Past research into the ability of students to 'bounce back' from everyday academic setback (academic buoyancy) has lacked sensitivity to the contexts in which children demonstrate this behavior. Here we aimed to contextualize past findings by reporting the results of an exploratory investigation that featured: (1) repeated measurement of students' self-reported buoyancy across English, mathematics, science, and physical education; (2) measures of students' psychological appraisal as a test of external validity; (3) a novel national context (England rather than Australia). In total 260 English secondary school students aged 11-16. years completed self-report questionnaires. Students were found to hold relatively consistent views about their ability to bounce back from everyday academic setbacks (e.g., negative feedback, poor results, study stress or pressure) compared to the relatively less consistent views they held regarding the difficulty of the four school subjects as well as corresponding personal competences and effort. These results are discussed in the context of past research, the implications for interventions, and the need for further confirmatory investigations
Academic buoyancy, student's achievement, and the linking role of control: A cross-lagged analysis of high school students
Background
Previous research has indicated that although academic buoyancy and student's achievement are associated, the relationship is relatively modest.
Aims
We sought to determine whether another construct might link academic buoyancy and student's achievement. Based on prior theoretical and empirical work, we examined a sense of control as one possible linking mechanism.
Sample
The study analysed data from 2,971 students attending 21 Australian high schools.
Methods
We conducted a cross-lagged panel design as a first means of disentangling the relative salience of academic buoyancy, control, and achievement (Phase 1). Based upon these results, we proceeded with follow-up analyses of an ordered process model linking the constructs over time (Phase 2).
Results
Findings showed that buoyancy and achievement were associated with control over time, but not with one another (Phase 1). In addition, control appeared to play a role in how buoyancy influenced achievement and that a cyclical process may operate among the three factors over time (Phase 2).
Conclusion
The findings suggest that control may play an important role in linking past experiences of academic buoyancy and achievement to subsequent academic buoyancy and achievement.The authors would like to thank the Australian Research Council for funding this research
The influence of different forms of early childcare on children's emotional and behavioural development at school entry
Background: Over the past few decades there has been a dramatic increase in maternal employment and, as a result, an increase in the use of non-maternal childcare in the early years. The purpose of this longitudinal study was to examine, in a large representative English sample, the influence of different forms of childcare on children's behavioural and emotional development around the age of school entry.
Methods: A sample of 991 families, originally recruited when the children were 3 months old, was assessed around school entry age at 51 months. The main outcome variable was the children's emotional and behavioural functioning, measured by questionnaire completed by both mothers and teachers. A range of repeated assessments were carried out at different time points, including direct observation of the quality of maternal caregiving and observations of the quality of non-parental care, and amount of time spent in different forms of care.
Results: The strongest and most consistent influences on behaviour and emotional problems were derived from the home, including lower socio-demographic status, poorer maternal caregiving, parental stress/maternal mental health problems, as well as child gender (being a boy). Non-parental childcare had small effects on child outcome. One finding that did emerge was that children who spent more time in group care, mainly nursery care, were more likely to have behavioural problems, particularly hyperactivity.
Conclusions: These findings suggest that interventions to enhance children's emotional and behavioural development might best focus on supporting families and augmenting the quality of care in the home
pfmdr1 amplification is related to increased Plasmodium falciparum In Vitro sensitivity to the Bisquinoline Piperaquine
The 4-aminoquinoline bisquinoline piperaquine is an important partner drug in one of the presently recommended artemisinin combination therapies. Recent clinical trials have confirmed its high efficacy in combination with dihydroartemisinin. Resistance to piperaquine alone has, however, been documented. Amplification in copy number of the Plasmodium falciparum multidrug resistance locus on chromosome 5, containing the pfmdr1 gene, has been shown to confer resistance to structurally unrelated antimalarials. Through the determination of the 50% inhibitory concentrations (IC(50)s) and IC(90)s for piperaquine and chloroquine in a set of 46 adapted P. falciparum cultures originating from the Thai-Burmese border, we have characterized the regions around the pfmdr1 gene and identified a significant association between the presence of pfmdr1 duplications and enhanced sensitivity to piperaquine (P = 0.005 for IC50 and P = 0.002 for IC90) and chloroquine, reaching statistical significance at IC(90)s (P = 0.026). These results substantiate the potential importance of pfmdr1 copy number amplifications in the efficacy of the combination therapy piperaquine-dihydroartemisinin. It supports the rational use of 4-aminoquinolines and artemisinin-based compounds, as they independently select for mutually incompatible combinations of mutations.Swedish Development Cooperation Agency-Department for Research Cooperation [SWE 2005-0017, SWE 2005-4596, SWE-2007-174, SWE-2005-4027]; Fundacao para a Ciencia e Tecnologia (FCT)/Ministerio da Ciencia e Ensino Superior, Portugal-MCES [SFRH/BPD/76614/2011]; Wellcome Trust of Great Britaininfo:eu-repo/semantics/publishedVersio
Introducció
Based on hypothesized reciprocal relations between psychological risk and academic buoyancy (dealing with ‘everyday’ academic setback in the ordinary course of school life), the present study used cross-lagged structural equation models to examine the relative salience of (1) prior academic buoyancy in predicting subsequent psychological risk and (2) prior psychological risk in predicting subsequent academic buoyancy. Academic buoyancy and psychological risk (academic anxiety, failure avoidance, uncertain control, emotional instability, neuroticism) measures were administered to 2971 students (11–19 years) from 21 Australian high schools at two time waves across a one-year interval. Analyses confirmed a reciprocal effects model in which psychological risk impacts academic buoyancy and academic buoyancy impacts psychological risk. The findings hold applied and conceptual implications for practitioners and researchers seeking to help students deal more effectively with adversity in school life
Can Admission and Fasting Glucose Reliably Identify Undiagnosed Diabetes in Patients With Acute Coronary Syndrome?
OBJECTIVE—Our objectives were to determine the prevalence of previously undiagnosed abnormal glucose tolerance, i.e., diabetes and impaired glucose tolerance (IGT) in patients with acute coronary syndrome and to assess the utility of admission and fasting glucose in identifying diabetes in these patients
Observation of dipole-mode vector solitons
We report on the first experimental observation of a novel type of optical
vector soliton, a {\em dipole-mode soliton}, recently predicted theoretically.
We show that these vector solitons can be generated in a photorefractive medium
employing two different processes: a phase imprinting, and a symmetry-breaking
instability of a vortex-mode vector soliton. The experimental results display
remarkable agreement with the theory, and confirm the robust nature of these
radially asymmetric two-component solitary waves.Comment: 4 pages, 8 figures; pictures in the PRL version are better qualit
Quasispecies Theory for Horizontal Gene Transfer and Recombination
We introduce a generalization of the parallel, or Crow-Kimura, and Eigen
models of molecular evolution to represent the exchange of genetic information
between individuals in a population. We study the effect of different schemes
of genetic recombination on the steady-state mean fitness and distribution of
individuals in the population, through an analytic field theoretic mapping. We
investigate both horizontal gene transfer from a population and recombination
between pairs of individuals. Somewhat surprisingly, these nonlinear
generalizations of quasi-species theory to modern biology are analytically
solvable. For two-parent recombination, we find two selected phases, one of
which is spectrally rigid. We present exact analytical formulas for the
equilibrium mean fitness of the population, in terms of a maximum principle,
which are generally applicable to any permutation invariant replication rate
function. For smooth fitness landscapes, we show that when positive epistatic
interactions are present, recombination or horizontal gene transfer introduces
a mild load against selection. Conversely, if the fitness landscape exhibits
negative epistasis, horizontal gene transfer or recombination introduce an
advantage by enhancing selection towards the fittest genotypes. These results
prove that the mutational deterministic hypothesis holds for quasi-species
models. For the discontinuous single sharp peak fitness landscape, we show that
horizontal gene transfer has no effect on the fitness, while recombination
decreases the fitness, for both the parallel and the Eigen models. We present
numerical and analytical results as well as phase diagrams for the different
cases.Comment: 54 pages; 8 figures; 12 tables; some typos corrected; to appear in
Phys. Rev.
WASP-23b: a transiting hot Jupiter around a K dwarf and its Rossiter-McLaughlin effect
We report the discovery of a new transiting planet in the Southern
Hemisphere. It has been found by the WASP-south transit survey and confirmed
photometrically and spectroscopically by the 1.2m Swiss Euler telescope, LCOGT
2m Faulkes South Telescope, the 60 cm TRAPPIST telescope and the ESO 3.6m
telescope. The orbital period of the planet is 2.94 days. We find it is a gas
giant with a mass of 0.88 \pm 0.10 Mj and a radius estimated at 0.96 \pm 0.05
Rj . We have also obtained spectra during transit with the HARPS spectrograph
and detect the Rossiter-McLaughlin effect despite its small amplitude. Because
of the low signal to noise of the effect and of a small impact parameter we
cannot place a constraint on the projected spin-orbit angle. We find two
confiicting values for the stellar rotation. Our determination, via spectral
line broadening gives v sin I = 2.2 \pm 0.3 km/s, while another method, based
on the activity level using the index log R'HK, gives an equatorial rotation
velocity of only v = 1.35 \pm 0.20 km/s. Using these as priors in our analysis,
the planet could either be misaligned or aligned. This should send strong
warnings regarding the use of such priors. There is no evidence for
eccentricity nor of any radial velocity drift with time.Comment: 13 pages, 8 figures, 7 tables, accepted for publication in A&
Stable vortex and dipole vector solitons in a saturable nonlinear medium
We study both analytically and numerically the existence, uniqueness, and
stability of vortex and dipole vector solitons in a saturable nonlinear medium
in (2+1) dimensions. We construct perturbation series expansions for the vortex
and dipole vector solitons near the bifurcation point where the vortex and
dipole components are small. We show that both solutions uniquely bifurcate
from the same bifurcation point. We also prove that both vortex and dipole
vector solitons are linearly stable in the neighborhood of the bifurcation
point. Far from the bifurcation point, the family of vortex solitons becomes
linearly unstable via oscillatory instabilities, while the family of dipole
solitons remains stable in the entire domain of existence. In addition, we show
that an unstable vortex soliton breaks up either into a rotating dipole soliton
or into two rotating fundamental solitons.Comment: To appear in Phys. Rev.
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