157 research outputs found
Sheath parameters for non-Debye plasmas: simulations and arc damage
This paper describes the surface environment of the dense plasma arcs that
damage rf accelerators, tokamaks and other high gradient structures. We
simulate the dense, non-ideal plasma sheath near a metallic surface using
Molecular Dynamics (MD) to evaluate sheaths in the non-Debye region for high
density, low temperature plasmas. We use direct two-component MD simulations
where the interactions between all electrons and ions are computed explicitly.
We find that the non-Debye sheath can be extrapolated from the Debye sheath
parameters with small corrections. We find that these parameters are roughly
consistent with previous PIC code estimates, pointing to densities in the range
. The high surface fields implied by these
results could produce field emission that would short the sheath and cause an
instability in the time evolution of the arc, and this mechanism could limit
the maximum density and surface field in the arc. These results also provide a
way of understanding how the "burn voltage" of an arc is generated, and the
relation between self sputtering and the burn voltage, while not well
understood, seems to be closely correlated. Using these results, and equating
surface tension and plasma pressure, it is possible to infer a range of plasma
densities and sheath potentials from SEM images of arc damage. We find that the
high density plasma these results imply and the level of plasma pressure they
would produce is consistent with arc damage on a scale 100 nm or less, in
examples where the liquid metal would cool before this structure would be lost.
We find that the sub-micron component of arc damage, the burn voltage, and
fluctuations in the visible light production of arcs may be the most direct
indicators of the parameters of the dense plasma arc, and the most useful
diagnostics of the mechanisms limiting gradients in accelerators.Comment: 8 pages, 16 figure
Towards a neurocognitive approach to Dance Movement Therapy for mental health: A systematic review
Dance/Movement Therapy (DMT) has become an increasingly recognized and used treatment, though primarily used to target psychological and physical wellbeing in individuals with physical, medical, or neurological illnesses. To contribute to the relative lack of literature within the field of DMT for clinical mental health disorders, using a narrative synthesis, we review the scope of recent, controlled studies of DMT in samples with different psychiatric disorders including depression, schizophrenia, autism, and somatoform disorder. A systematic search of electronic databases (PubMed, Science Direct, World of Science, and Clinicaltrials.gov) was conducted to identify studies examining the effects of DMT in psychiatric populations. 15 studies were eligible for inclusion. After reviewing the principal results of the studies, we highlight strengths and weaknesses of this treatment approach and examine the potential efficacy of using bodily movements as a tool to reduce symptoms. We conclude by placing DMT within the context of contemporary cognitive neuroscience research, drawing out implications of such an orientation for future research, and discussing potential mechanisms by which DMT might reduce psychiatric symptoms. DMT has clear potential as a treatment for a range of conditions and symptoms and thus further research on its utility is warranted
On Early Applications of Psychology in Music Education
Granville Stanley Hall, founder of the American Psychological Association and president of Clark University, was the first American psychologist to speak and write about music's place in the educational curriculum. An examination of his published writings reveals Hall based his theory of music education on principles of Social Darwinism and Child Study perspectives on education. Hall's theories are referenced and paraphrased in several song series textbooks and music appreciation texts published by music educators during his professional career. These sources indicate that Hall influenced the thinking of certain music educators and was important to music education, in general, in developing a receptivity toward psychological processes in music education practice.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Comparative bioavailability: Eight commercial prednisone tablets
Two four-treatment crossover bioavailability studies were performed in panels of 12 adult male volunteers with eight different commercial prednisone tablets. Plasma samples from the first study were assayed by radioimmunoassay for both prednisone and prednisolone. Plasma samples from the second study were assayed for prednisolone only. Statistical analyses of the data showed significant differences in the rate of appearance of prednisolone in plasma, but not in the amount convened to prednisolone. Some observations are made on the relationships between prednisone and prednisolone concentrations in plasma following oral administration of prednisone .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45064/1/10928_2005_Article_BF01086151.pd
Association of acute toxic encephalopathy with litchi consumption in an outbreak in Muzaffarpur, India, 2014: a case-control study
Background Outbreaks of unexplained illness frequently remain under-investigated. In India, outbreaks of an acute
neurological illness with high mortality among children occur annually in Muzaffarpur, the country’s largest litchi
cultivation region. In 2014, we aimed to investigate the cause and risk factors for this illness.
Methods In this hospital-based surveillance and nested age-matched case-control study, we did laboratory
investigations to assess potential infectious and non-infectious causes of this acute neurological illness. Cases were
children aged 15 years or younger who were admitted to two hospitals in Muzaffarpur with new-onset seizures or
altered sensorium. Age-matched controls were residents of Muzaffarpur who were admitted to the same two hospitals
for a non-neurologic illness within seven days of the date of admission of the case. Clinical specimens (blood,
cerebrospinal fluid, and urine) and environmental specimens (litchis) were tested for evidence of infectious
pathogens, pesticides, toxic metals, and other non-infectious causes, including presence of hypoglycin A or
methylenecyclopropylglycine (MCPG), naturally-occurring fruit-based toxins that cause hypoglycaemia and metabolic
derangement. Matched and unmatched (controlling for age) bivariate analyses were done and risk factors for illness
were expressed as matched odds ratios and odds ratios (unmatched analyses).
Findings Between May 26, and July 17, 2014, 390 patients meeting the case definition were admitted to the two referral
hospitals in Muzaffarpur, of whom 122 (31%) died. On admission, 204 (62%) of 327 had blood glucose concentration
of 70 mg/dL or less. 104 cases were compared with 104 age-matched hospital controls. Litchi consumption (matched
odds ratio [mOR] 9·6 [95% CI 3·6 – 24]) and absence of an evening meal (2·2 [1·2–4·3]) in the 24 h preceding illness
onset were associated with illness. The absence of an evening meal significantly modified the effect of eating litchis
on illness (odds ratio [OR] 7·8 [95% CI 3·3–18·8], without evening meal; OR 3·6 [1·1–11·1] with an evening meal).
Tests for infectious agents and pesticides were negative. Metabolites of hypoglycin A, MCPG, or both were detected in
48 [66%] of 73 urine specimens from case-patients and none from 15 controls; 72 (90%) of 80 case-patient specimens
had abnormal plasma acylcarnitine profiles, consistent with severe disruption of fatty acid metabolism. In 36 litchi
arils tested from Muzaffarpur, hypoglycin A concentrations ranged from 12·4 μg/g to 152·0 μg/g and MCPG ranged
from 44·9 μg/g to 220·0 μg/g.
Interpretation Our investigation suggests an outbreak of acute encephalopathy in Muzaffarpur associated with both
hypoglycin A and MCPG toxicity. To prevent illness and reduce mortality in the region, we recommended minimising
litchi consumption, ensuring receipt of an evening meal and implementing rapid glucose correction for suspected
illness. A comprehensive investigative approach in Muzaffarpur led to timely public health recommendations,
underscoring the importance of using systematic methods in other unexplained illness outbreaks
- …