1,157 research outputs found
Up and down the number line: modelling collaboration in contrasting school and home environments
This paper is concerned with user modelling issues such as adaptive educational environments, adaptive information retrieval, and support for collaboration. The HomeWork project is examining the use of learner modelling strategies within both school and home environments for young children aged 5 – 7 years. The learning experience within the home context can vary considerably from school especially for very young learners, and this project focuses on the use of modelling which can take into account the informality and potentially contrasting learning styles experienced within the home and school
Improving water quality assessment and supply
Over 90 per cent of avaiable freshwater in the Arusha region of Northern Tanzania is abstracted from groundwater aquifers. The majority of this is from regolithhosted or alluvial hosted groundwater aquifers situated within 30 m of the surface. Historically this weathered mantle was assumed to protect groundwater from contamination and it is only recently that water quality has
been monitored (Coster, 1950; Wateraid, 1991). It has been demonstrated that the biogeochemical processes influencing water quality are complex (Lahermo et al., 1991; Mjengera, 1991; Smith et al., 1996; Bowell et al., 1996). The aim of this paper is to describe the relationships between water chemistry and microbiological activity in
protolith (collected below 30m, hosted by unweathered bedrock), regolith (above 30m, water hosted in the weathered
rocks and soils) and alluvial hosted groundwaters in urban (Arusha district) and rural areas (Hanang, Mbulu and Babati districts) of the Arusha region, Tanzania. An assessment is made of possible advantages and disadvantages
in utilising the various groundwaters as supplies of potable water and in potential treatment options
Displaying the Heterogeneity of the SN 2002cx-like Subclass of Type Ia Supernovae with Observations of the Pan-STARRS-1 Discovered SN2009ku
SN2009ku, discovered by Pan-STARRS-1, is a Type Ia supernova (SNIa), and a
member of the distinct SN2002cx-like class of SNeIa. Its light curves are
similar to the prototypical SN2002cx, but are slightly broader and have a later
rise to maximum in g. SN2009ku is brighter (~0.6 mag) than other SN2002cx-like
objects, peaking at M_V = -18.4 mag - which is still significantly fainter than
typical SNeIa. SN2009ku, which had an ejecta velocity of ~2000 kms^-1 at 18
days after maximum brightness is spectroscopically most similar to SN2008ha,
which also had extremely low-velocity ejecta. However, SN2008ha had an
exceedingly low luminosity, peaking at M_V = -14.2 mag, ~4 mag fainter than
SN2009ku. The contrast of high luminosity and low ejecta velocity for SN2009ku
is contrary to an emerging trend seen for the SN2002cx class. SN2009ku is a
counter-example of a previously held belief that the class was more homogeneous
than typical SNeIa, indicating that the class has a diverse progenitor
population and/or complicated explosion physics. As the first example of a
member of this class of objects from the new generation of transient surveys,
SN2009ku is an indication of the potential for these surveys to find rare and
interesting objects.Comment: 7 pages, 3 figure
A comparative study of the dynamic critical behavior of the four-state Potts like models
We investigate the short-time critical dynamics of the Baxter-Wu (BW) and
Turban (3TU) models to estimate their global persistence exponent . We conclude that this new dynamical exponent can be useful in detecting
differences between the critical behavior of these models which are very
difficult to obtain in usual simulations. In addition, we estimate again the
dynamical exponents of the four-state Potts (FSP) model in order to compare
them with results previously obtained for the BW and 3TU models and to decide
between two sets of estimates presented in the current literature. We also
revisit the short-time dynamics of the 3TU model in order to check if, as
already found for the FSP model, the anomalous dimension of the initial
magnetization could be equal to zero
Drivers of change in crop–livestock systems and their potential impacts on agro-ecosystems services and human wellbeing to 2030: A study commissioned by the CGIAR Systemwide Livestock Programme
A Study commissioned by the CGIAR Systemwide Livestock Programm
Oral oncology parity laws, medication use, and out-of-pocket spending for patients with blood cancers
Background: In this study, we sought to estimate the association between oral oncology parity law adoption and anticancer medication use for patients with chronic myeloid leukemia or multiple myeloma. Methods: This was an observational study of administrative claims from 2008 to 2017. Among individuals initiating tyrosine kinase inhibitors (TKIs) for chronic myeloid leukemia or immunomodulatory drugs for multiple myeloma, we compared out-of-pocket spending, adherence, and discontinuation before and after parity among individuals in fully insured plans (subject to parity) vs self-funded plans (exempt from parity) using propensity-score weighted difference-in-differences regression models. Results: Among patients initiating TKIs (N = 2082) or immunomodulatory drugs (N = 3326) there were no statistically significant differences in adherence or discontinuation associated with parity. The proportion of patients with initial out-of-pocket payments of 100 decreased from 30.3% to 24.7% for TKIs and 30.6% to 27.5% for immunomodulatory drugs in fully insured plans after parity. Relative to changes in self-funded plans, those in fully insured plans were 0.74 (95% CI = 0.54 to 1.01) times as likely to pay more than 100 for immunomodulatory drugs after parity. Conclusions: Among patients initiating TKIs or immunomodulatory drugs, parity was not associated with better adherence or less discontinuation of therapy but yielded decreased patient out-of-pocket payments for some patients
A single-center, observational study of 607 children & young people presenting with Differences in Sex Development (DSD)
Context
Differences in sex development (DSD) represent a wide range of conditions presenting at different ages to various health professionals. Establishing a diagnosis, supporting the family and developing a management plan are important.
Objective
We aimed to better understand the presentation and prevalence of pediatric DSD.
Design
A retrospective, observational cohort study was undertaken of all children and young people (CYP) referred to a DSD multi-disciplinary team over 25 years (1995-2019).
Setting
A single tertiary paediatric center.
Participants
In total, 607 CYP (520 regional referrals) were included.
Main Outcome Measures
Data were analyzed for diagnosis, sex-assignment, age and mode of presentation, additional phenotypic features, mortality, and approximate point prevalence.
Results
Amongst the three major DSD categories, sex chromosome DSD was diagnosed in 11.2% (68/607) (most commonly 45, X/46, XY mosaicism), 46, XY DSD in 61.1% (371/607) (multiple diagnoses often with associated features), while 46, XX DSD occurred in 27.7% (168/607) (often 21-hydroxylase deficiency). Most children (80.1%) presented as neonates, usually with atypical genitalia, adrenal insufficiency, undescended testes or herniae. Those presenting later had diverse features. Rarely, the diagnosis was made antenatally (3.8%, n = 23) or following incidental karyotyping/family history (n = 14). Mortality was surprisingly high in 46, XY children, usually due to complex associated features (46, XY girls, 8.3%; 46, XY boys, 2.7%). The approximate point prevalence of neonatal referrals for investigation of DSD was 1 in 6,347 births, and 1 in 5,101 overall throughout childhood.
Conclusions
DSD represent a diverse range of conditions that can present at different ages. Pathways for expert diagnosis and management are important to optimize care
Production and Decay of D_1(2420)^0 and D_2^*(2460)^0
We have investigated and final states and
observed the two established charmed mesons, the with mass
MeV/c and width MeV/c and
the with mass MeV/c and width
MeV/c. Properties of these final states, including
their decay angular distributions and spin-parity assignments, have been
studied. We identify these two mesons as the doublet predicted
by HQET. We also obtain constraints on {\footnotesize } as a function of the cosine of the relative phase of the two
amplitudes in the decay.Comment: 15 pages in REVTEX format. hardcopies with figures can be obtained by
sending mail to: [email protected]
Measurement of the branching fraction for
We have studied the leptonic decay of the resonance into tau
pairs using the CLEO II detector. A clean sample of tau pair events is
identified via events containing two charged particles where exactly one of the
particles is an identified electron. We find . The result is consistent with
expectations from lepton universality.Comment: 9 pages, RevTeX, two Postscript figures available upon request, CLNS
94/1297, CLEO 94-20 (submitted to Physics Letters B
Self-regulation and self-control in exercise: The strength-energy model
Self-regulation is an important component of psychosocial theories of exercise behaviour and lack of self-regulatory skills are associated with low adherence to health-related exercise. This review presents a strength-energy model of self-control as an explanation of self-regulation in exercise contexts. The review will provide impetus for original research aimed at understanding exercise behaviour and help develop recommendations for exercise promotion. In the model, self-control is conceptualized as a global but limited resource. Engaging in actions requiring self-control depletes resources leading to self-regulatory failure. Self-control resource depletion is reduced through rest and frequent training on self-control. The expectation of the need to exert self-control in future leads to a conservation of self-control resources. Proposed mechanisms for self-control resource depletion include changes in physiological markers and blood glucose levels. Based on our review, we propose an integrated model of self-regulation incorporating hypotheses from the strength-energy model with those from traditional psychosocial models of exercise behaviour. Recommendations for future research include incorporating hypotheses from the strength-energy model into theories of self-presentation and interpersonal relations in exercise. Practical recommendations aimed at minimising self-control depletion in exercise include the provision of advice on nutrition and recovery, self-control training and motivational and implementation intention strategies
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