349 research outputs found
Excitation Mechanisms of the Nitrogen FirstâPositive and FirstâNegative Radiation at High Temperature
The kinetic mechanisms responsible for the excitation of the first-positive and first-negative emission
of nitrogen have been investigated in a re-examination of previously reported shock-tube measurements
of the nonequilibrium radiation for these systems. The rate coefficients of the collisional quenching reactions, N_2(A^(3)ÎŁ^(+)_u)(^(k^(N)_(-2))â) N_2(X^(1)ÎŁ^(+)_g) + N(^(4)S) and N^(+)_2(B^(2)ÎŁ^(+)_u) + N_2(X^(1)ÎŁ^(+)_g)(^(k^(N)_(q))â) N^(+)_2(X^(2)ÎŁ^(+)_g) or N^(+)_2(A(^(2)II_u)+N_2(X^(1)ÎŁ^(+)_g)
were found to be given by the empirical expressions, k_(2^(N))=5.1x10^(-3)T^(-2.23) cm^3 sec^(-1) and k_(q^(N_2))=1.9x10^(-2)T^(-2.33)cm^3 sec^(-1), respectively, over the approximate temperature range 6000-14 000°K
Reforms in Japanese Criminal Procedure Under Allied Occupation
In the past, reforms in Japanese criminal procedure would have been of little interest to most Americans, who have never felt it important to understand foreign legal systems. Fortunately, this attitude is beginning to change. Moreover, the United States has been officially committed to encourage a desire for individual liberties and democratic processes on the part of the Japanese people since the Potsdam Declaration of July 26, 1945. Consequently, Americans will be interested in the postwar reforms in Japanese criminal procedure, if only to be fully informed of progress toward fulfillment of the objectives of the Allied Occupation, in which the United States has played the leading role
Examining perfectionism in elite junior athletes : measurement and development issues
The major theme of the current thesis was the definition, measurement, and development of perfectionism in elite junior sport. The first purpose was to examine the psychometric properties associated with Hewitt and Flettâs (1991) Multidimensional Perfectionism Scale (MPS-HF) when complete by a sample of elite junior athletes. In study one, a confirmatory factor analysis failed to support the original structure of 45-item MPS-HF. Subsequent exploratory and confirmatory factor analyses revealed a more parsimonious 15-item factor structure representing self-oriented (SOP), socially prescribed (SPP), and other-oriented perfectionism (OOP). Having established a reconstituted version of the MPS-HF, a second purpose of the research programme was to consider the origins of perfectionism in elite junior athletes using a cross-sectional design. Initially, in study two a social learning model was supported, with 18%-26% of variance in athletesâ perfectionism predicted by parentsâ perfectionism. Building upon this finding in study three, a structural equation model revealed that parenting styles, including empathy and psychological control, mediated the parent-athletic child SPP relationship. In study four, a significant pathway emerged between parentsâ achievement goals and athletesâ dispositional perfectionism, offering support for a social expectations model of perfectionism development. Specifically, parentsâ task and ego orientations were positively associated with athletesâ SOP. In contrast, athletesâ SPP was predicted by parentsâ ego orientation. Study four also demonstrated the nature and form of motivational regulation associated with athletesâ SOP and SPP. That is, a pathway emerged between athletesâ SPP and controlled forms of regulation, while athletesâ SOP was correlated with self-determined and controlled motivation. Finally, in study five, the coach-created motivational climate accounted for approximately 19% of variance in athletesâ perfectionistic cognitions, highlighting the role of additional social agents in the development of athletesâ perfectionism. The results of this research programme contribute to existing knowledge of perfectionism by forwarding reliable measures of SOP and SPP for employment in sport, and revealing a complex array of pathways that underpin the development of perfectionism in elite junior athletes.
Ultimately, by preventing the occurrence of such pathways, athletic children may be protected from the perils of perfectionism
Transitional services for adolescents with epilepsy in the UK: A survey
AbstractPurposeTo survey the current transitional epilepsy services in tertiary paediatric neurology centres in the UK within the principles of transitional care for young people with epilepsy.MethodsAn online web-based questionnaire was sent to the lead epilepsy clinicians in tertiary paediatric neurology centres on behalf of the British Paediatric Epilepsy Group, the specialist epilepsy group of the British Paediatric Neurology Association (BPNA). A transition clinic was defined as a âclinic or service that provided joint paediatric and adult supervision of care from paediatric to adult servicesâ.ResultsTwenty-three centres were approached of which18 responded and 15 of which provided auditable data. The clinics were held between three and 12 times per year, mostly in the afternoon and sited equally between the paediatric and adult centre. Approximately three to five new, and three to eight follow up patients were seen in each clinic. Most clinics accepted new referrals with a minimum age of 14 and a maximum of 20 years. Most young people were seen only once in a transition clinic before then being promoted into the adult epilepsy service. Very few clinics accepted direct referrals from the GP. Adult, slightly more than the paediatric team provided out-of-hospital advice after the young person was seen in the transition clinic.ConclusionsYoung people with epilepsy are a challenging, but interesting group and their care at this time may have a potentially irreversible impact on their life. Their progress from paediatric to adult services should be a dynamic, gradual and smoothly transitioned process to optimise their care. Although recommended by the National Institute for Health and Clinical Excellence (NICE) and the National Services Framework (NSF), the findings of this survey would suggest an un-met need of this population
Withholding the choice of sodium valproate to young women with generalised epilepsy: Are we causing more harm than good?
PURPOSE: Although sodium valproate (VPA) remains the most effective antiepileptic for generalised and unclassified epilepsies, clinicians may be failing to discuss this treatment option because of guideline misinterpretation. Current guidelines recommend caution regarding teratogenic risks but do not advocate absolute avoidance. METHOD: We assessed VPA prescribing in young people attending a transition epilepsy clinic. We present six patients with idiopathic generalised epilepsy (IGE) in whom VPA had been initially avoided. RESULTS: Overall, the results were consistent with VPA's superior antiepileptic efficacy and ability to reduce harmful seizure-related complications. Young people denied of VPA showed prolonged periods of poor seizure control with medical, social and psychological complications. Following contraceptive counselling and VPA introduction, all six patients showed improved seizure control including seizure-freedom during follow-up of up to twenty-four months. There was also evidence of reduced seizure-related morbidity and improved educational and occupational functioning. Prior to referral, documentation revealed no discussion of VPA treatment options. CONCLUSION: Failure to prescribe valproate for IGE, particularly when another first-line treatment has failed, may not be in a young woman's best interests-particularly when they are most vulnerable to sequelae from uncontrolled seizures. Indiscriminate avoidance of valproate needs to be recognised as a misinterpretation of current epilepsy guidelines as it may harm young people. Although the use of valproate demands careful consideration, there remains a strong case to always discuss this medication because of its efficacy and potential to reduce seizure-related harm. Patients must be allowed to make their own informed decisions about effective epilepsy treatments.NoneThis is the author's accepted manuscript. The final version is available from Elsevier at: http://www.sciencedirect.com/science/article/pii/S1059131114002349
Comparing paediatric intravenous phenytoin doses using physiologically based pharmacokinetic (PBPK) modelling software
AbstractPurposeTo use a physiologically based pharmacokinetic (PBPK) modelling system to predict the serum levels achieved by two different intravenous loading doses of phenytoin.MethodsA phenytoin pharmacokinetic model was used in the Simcypâą population-based ADME simulator, simulating 100 children age 2â10 years receiving intravenous phenytoin (18 and 20mg/kg). Visual checks were used to evaluate the predictive performance of the candidate model.ResultsLoading with doses of 18mg/kg, blood levels were sub-therapeutic in 22/100 (concentration at 2h post infusion (C2h) <10ÎŒg/mL), therapeutic in 62/100 (C2h 10â20ÎŒg/mL), and supra-therapeutic in 16/100 (C2h>20ÎŒg/mL). Loading with 20mg/kg, the percentages were 15, 59, and 26, respectively. Increasing from 18 to 20mg/kg increased the mean C2h from 16.0 to 17.9ÎŒg/mL, and the mean AUC from 145 to 162ÎŒg/mL/h. A C2h>30ÎŒg/mL was predicted in 4% and 8% of children in the 18 and 20mg/kg doses, with 3% predicted to have a C2h>40ÎŒg/mL following either dose. For maintenance doses, a 1st dose of 2.5 or 5mg/kg (intravenous) given at 12h (after either 18 or 20mg/kg loading) gives the highest percentages of 10â20ÎŒg/mL serum concentrations. For sub-therapeutic concentrations following intravenous loading (20mg/kg), a 1st maintenance dose (intravenous) of 10mg/kg will achieve therapeutic concentrations in 93%.ConclusionUse of PBPK modelling suggests that children receiving the 20mg/kg intravenous loading dose are at slightly increased risk of supra-therapeutic blood levels. Ideally, therapeutic drug monitoring is required to monitor serum concentrations, although the dose regime suggested by the BNFc appear appropriate
THE BIVALVES OF THE SPILSBY SANDSTONE FORMATION AND CONTIGUOUS DEPOSITS
PhDHitherto the bivalve fauna of the Spilsby Sandstone and contiguous
deposits including the lower part of the Sandringham Sands and Speeton
Clay of-Middle Volgian to Ryazanian age has been inadequately described.
As a consequence of this study 92 taxa have been recorded. 45 of these
are described fully and include 13 new species and one new subgenus.
Information has been obtained from the author's collecting and from museum'
collections. Locality and section information is given for sites examined
by the author. The preservation of the fauna is normally as moulds, but
cold cure silicone rubber has been used to obtain casts with great success.
The ecology of the less well understood bivalves is discussed.
Five bivalve dominated assemblages are recognised. They represent various
shallow marine facies. The sediments include glauconitic sands and silts
with condensed sequences containing phosphatised nodules and also a
sideritic ironstone occurs. A facies model is produced for the East
Midlands Shelf, and the contemporary relationships with other parts of
England are discussed. The Spilsby basin represents a westerly embayment
or estuary of the Southern North Sea basin. In Middle Volgian times there
were marine connections to the Wessex basin to the south, but with the
subsequent draining of this latter area in Upper Volgian to Ryazanian
times to restricted marine, brackish and freshwater lagoonal environments,
open marine connection ceased. The Spilsby basin remained fully marine
during these times, but became more enclosed.
The Spilsby bivalve fauna indicates strong faunal similarities
with Boreal regions, and in particular with East Greenland and the Russian
Platform. The fauna also compares closely with the sandy Upper Kimmeridgian
facies in central England but contrasts strongly with the contemporary
faunas of the Portland and Purbeck Beds. The relationships of the Spilsby
fauna with other Boreal regions and with Tethyan Europe are discussed
Probing the Evolution of the Galaxy Interaction/Merger Rate Using Collisional Ring Galaxies
We present the results from our program to determine the evolution of the
galaxy interaction/merger rate with redshift using the unique star-forming
characteristics of collisional ring galaxies. We have identified 25 distant
collisional ring galaxy candidates (CRGCs) in a total of 162 deep Hubble Space
Telescope Wide Field/Planetary Camera-2 images obtained from the HST Archives.
Based on measured and estimated redshifts, these 25 CRGCs all lie in the
redshift interval of 0.1 < z < 1. Using the local collisional ring galaxy
volume density and the new ``standard'' cosmology, we find that in order to
account for the number of identified CRGCs in our surveyed fields, the galaxy
interaction/merger rate, parameterized as (1 + z)^m, must increase steeply with
redshift.We determine a minimum value of m = 5.2 0.7, though m could be
as high as 7 or 8. We can rule out a non-evolving (m = 0) and weakly evolving
(m = 1-2) galaxy interaction/merger rate at greater than the 4 sigma level of
confidence.Comment: Accepted in the Astrophysical Journal (11 pages, 4 figures). Higher
resolution version of the figures is available at
http://www.astro.cornell.edu/~vassilis/papers
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