2,032 research outputs found
Intestinal neuromuscular function after preservation and transplantation
While it is well known that prolonged preservation of the intestinal graft causes severe mucosal damage after transplantation, little is known about the effect on neuromuscular function. The entire small intestine of adult hound dogs was flushed and preserved with cold lactated Ringer's solution and autotransplanted either immediately (n = 6) or after 24 hr (n = 6). Animals undergoing sham operation (n = 4) were used as a control. Fasting motility and the response of the intestinal smooth muscle and enteric nerves to bethanechol (100 μg/kg/0.5 hr, iv) and cisapride (0.5 mg/kg, iv) were determined by a multiple strain gauge method on Postoperative Days 2, 4, 7, 14, 21, and 28. Compared to the control, immediately transplanted grafts and those preserved for 24 hr developed delayed reappearance of migrating myoelectric complexes (MMC), hypercontractile activity, and reduced response to bethanechol and cisapride administration. Animals in the preservation group developed more abnormal fasting motility after transplantation, but responses to bethanechol and cisapride stimulation were not markedly different from those of the immediate group. The reappearance of MMC occurred 3 weeks postoperatively in the preservation group compared to 2 days in the immediate group. The results of our study indicate that intestinal dysmotility is augmented in prolonged-preservation grafts compared to those with brief preservation. The dysmotility was transient and normalized 3 to 4 weeks after surgery. Preservation and reperfusion injury to the neuromuscular system of intestinal grafts are reversible and are attenuated by simple hypothermia
Reducing the Effects of Unequal Number of Games on Rankings
Ranking is an important mathematical process in a variety of contexts such as information retrieval, sports and business. Sports ranking methods can be applied both in and beyond the context of athletics. In both settings, once the concept of a game has been defined, teams (or individuals) accumulate wins, losses, and ties, which are then factored into the ranking computation. Many settings involve an unequal number of games between competitors. This paper demonstrates how to adapt two sports rankings methods, the Colley and Massey ranking methods, to settings where an unequal number of games are played between the teams. In such settings, the standard derivations of the methods can produce nonsensical rankings. This paper introduces the idea of including a super-user into the rankings and considers the effect of this fictitious player on the ratings. We apply such techniques to rank batters and pitchers in Major League baseball, professional tennis players, and participants in a free online social game. The ideas introduced in this paper can further the scope that such methods are applied and the depth of insight they offer
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An evaluation of mercury removal in the IDMS using the nitric acid flowsheet
The present DWPF flowsheet calls for the chemical treatment of waste sludge with 90 wt % formic acid prior to the addition of the Precipitate Hydrolysis Aqueous (PHA) product. An alternative processing methodology, denoted the Nitric Acid Flowsheet'', has been proposed. in the application of this flowsheet, nitric acid would be used to neutralize sludge base components (hydroxides and carbonates) prior to the addition of late wash PHA. The late wash PHA will contain sufficient quantities of formic acid to adequately complete necessary reduction-oxidation (REDOX) reactions
The neurobiological basis of binge-eating disorder
AbstractRelatively little is known about the neuropathophysiology of binge-eating disorder (BED). Here, the evidence from neuroimaging, neurocognitive, genetics, and animal studies are reviewed to synthesize our current understanding of the pathophysiology of BED. Binge-eating disorder may be conceptualized as an impulsive/compulsive disorder, with altered reward sensitivity and food-related attentional biases. Neuroimaging studies suggest there are corticostriatal circuitry alterations in BED similar to those observed in substance abuse, including altered function of prefrontal, insular, and orbitofrontal cortices and the striatum. Human genetics and animal studies suggest that there are changes in neurotransmitter networks, including dopaminergic and opioidergic systems, associated with binge-eating behaviors. Overall, the current evidence suggests that BED may be related to maladaptation of the corticostriatal circuitry regulating motivation and impulse control similar to that found in other impulsive/compulsive disorders. Further studies are needed to understand the genetics of BED and how neurotransmitter activity and neurocircuitry function are altered in BED and how pharmacotherapies may influence these systems to reduce BED symptoms
Rotational quenching of CO due to H collisions
Rate coefficients for state-to-state rotational transitions in CO induced by
both para- and ortho-H collisions are presented. The results were obtained
using the close-coupling method and the coupled-states approximation, with the
CO-H interaction potential of Jankowski & Szalewicz (2005). Rate
coefficients are presented for temperatures between 1 and 3000 K, and for
CO() quenching from to all lower levels. Comparisons
with previous calculations using an earlier potential show some discrepancies,
especially at low temperatures and for rotational transitions involving large
. The differences in the well depths of the van der Waals
interactions in the two potential surfaces lead to different resonance
structures in the energy dependence of the cross sections which influence the
low temperature rate coefficients. Applications to far infrared observations of
astrophysical environments are briefly discussed.Comment: 28 pages, 10 figure
Large Effects of Electric Fields on Atom-Molecule Collisions at Millikelvin Temperatures
Controlling interactions between cold molecules using external fields can
elucidate the role of quantum mechanics in molecular collisions. We create a
new experimental platform in which ultracold rubidium atoms and cold ammonia
molecules are separately trapped by magnetic and electric fields and then
combined to study collisions. We observe inelastic processes that are faster
than expected from earlier field-free calculations. We use quantum scattering
calculations to show that electric fields can have a major effect on collision
outcomes, even in the absence of dipole-dipole interactions.Comment: 5 pages, 4 figure
Calculating energy levels of isomerizing tetra-atomic molecules. II. The vibrational states of acetylene and vinylidene
A general, full-dimensional computational method for the accurate calculation of rotationally and vibrationally excited states of tetra-atomic molecules is further developed. The resulting computer program may be run in serial and parallel modes and is particularly appropriate for molecules executing wide-amplitude motions and isomerizations. An application to the isomerizing acetylene∕vinylidene system is presented. Large-scale calculations using a coordinate system based on orthogonal satellite vectors have been performed in six dimensions and vibrational term values and wave functions for acetylene and vinylidene states up to ≈23000cm−1 above the potential minimum have been determined. This has permitted the characterization of acetylene and vinylidene states at and above the isomerization barrier. These calculations employ more extensive vibrational basis sets and hence consider a much higher density of states than in any variational calculations reported hitherto for this system. Comparison of the calculated density of states with that determined empirically suggests that our calculations are the most realistic achieved for this system to date. Indeed more states have been converged than in any previous study of this system. Calculations on lower lying excited states of acetylene based on HC–CH diatom-diatom coordinates give nearly identical results to those based on orthogonal satellite vectors. Comparisons are also made with calculations based on HH–CC diatom-diatom coordinates
Calculating energy levels of isomerizing tetra-atomic molecules. I. The rovibrational bound states of Ar2HF
A general, six-dimensional computational method for the accurate calculation of rotationally and vibrationally excited states of tetra-atomic molecules is developed. The resulting program is particularly appropriate for molecules executing wide-amplitude motions and isomerizations. An application to the Ar2HF van der Waals trimer is presented in which the HF intramolecular stretching coordinate is separated out adiabatically and is not treated explicitly. Vibrational term values up to about 100 cm−1 with absolute convergence to better than 0.1 cm−1 are reported. These calculations employ more extensive vibrational basis sets and hence consider a much higher density of states than hitherto. States that sample Ar–Ar–HF linear configurations and approach Ar–HF–Ar linear configurations are characterized for the first time. Results for total angular momentumJ=0 and 1 provide the first accurate calculations of rotational constants for this system. The rotational constants for the HF bending states of Ar2HF in the ground and first vibrationally excited states of the HF monomer are in good agreement with experiment, confirming the accuracy of the potential used in this work
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Young Offenders in Prison – perceptions of mental health disorders and their treatment: a qualitative study
Aim: To explore the understanding of young offenders about the mental health issues that affect them whilst incarcerated, and what support they require.
Background: The mental health needs of young people in prison continue to pose a serious health problem for the individuals concerned and for society as a whole. Violent behaviour, towards others and towards the self, remains a disturbing problem. This study addresses the issue from the perspective of the young people themselves through interviews with young offenders currently serving custodial sentences. Method Qualitative interview study with thematic analysis. Setting Twenty in-depth interviews with young people (10 males and 10 females) in 2 Young Offenders Institutions.
Participants: 16-20 year old young offenders, completing sentences in Young Offender Institutions in England. Results Awareness of a range of mental health issues existed among all of the participants. At the same time, there was widespread prejudice towards those with mental health difficulties despite personal experiences of difficulty and day-to-day observation of peers in distress. Participants appreciated the information and treatment that they received on drugs, alcohol and substance abuse but felt that this input took place at the expense of treating other mental health difficulties. They reported over-use of medication, some inappropriate prescribing practices and a dearth of therapeutic interventions such as counselling. They reported suspicion of in-house support because of the lack of trust inherent in the prison environment.
Conclusion: Young people in custody are a particularly vulnerable group with a strong need for appropriate information about mental health issues and the provision of counselling and other forms of social support to alleviate their distress. Nursing and counselling staff in prisons potentially play a critical role in addressing this urgent issue by focussing on the emotional and educational needs of young offenders. Nurses currently tend to fulfil a medical role in prisons, prescribing medication, but additional counselling based training seems an appropriate way forward so that nurses are empowered to address their mental health issues in a holistic way
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