Semiclassical collision theory. Multidimensional integral method

Numerical results on the integral expression for the semiclassical S matrix are compared with exact quantum results for a multidimensional problem. The collision of a rigid rotor with an atom is treated. The integral method proves to be easy to apply. Within its range of maximum validity (no sign changes in the pre‐exponential factor of the semiclassical wavefunction) the agreement was typically within 20%. When sign changes occurred, the agreement was about a factor of 2 or better. Conditions affecting sign changes are described

Semiclassical collision theory. Multidimensional Bessel uniform approximation

A multidimensional Bessel uniform approximation for the semiclassical S matrix is derived for the case of four real stationary phase points. A formula is also developed for the particular case when four stationary phase points may be considered to be well separated in pairs. The latter equation is then used in the treatment of two real and two complex stationary phase points

Semiclassical collision theory. Application of multidimensional uniform approximations to the atom-rigid-rotor system

The multidimensional Bessel and Airy uniform approximations developed earlier in this series for the semiclassical S matrix are applied to the atom rigid−rotor system. The need is shown for (a) using a geoemetrical criterion for determining whether a stationary phase point (s.p.pt) is a maximum, minimum, or saddle point; (b) choosing a proper quadrilateral configuration of the s.p.pts. with the phases as nearly equal as possible; and (c) choosing a unit cell to favor near−separation of variables. (a) and (b) apply both to the Airy and to the Bessel uniform approximations, and (c) to the Bessel. The use of a contour plot both to understand and to facilitate the search in new cases is noted. The case of real and complex−valued stationary phase points is also considered, and the Bessel uniform−in−pairs approximation is applied. Comparison is made with exact quantum results. As in the one−dimensional case, the Bessel is an improvement over the Airy for ’’k = 0’’ transitions, while for other transitions they give similar results. Comparison in accuracy with the results of the integral method is also given. As a whole, the agreement can be considered to be reasonable. The improvement of the present over various more approximate results is shown

Evolving empowerment in an online community collection memories of Amsterdam East

In this article we study the evolvement of empowering and dis-empowering aspects of a local memory website, initiated by the Amsterdam Museum and currently active for more than a decade. The results partly fill a gap in the available literature about this field, because the relation between collective empowerment and online behaviour in these communities has been underexposed. Departing from a narrative perspective on memories as resources for empowerment, we show how the online dynamics around these memories exhibit collective processes of identity formation, social learning and networking. However, certain patterns in the online dynamics also uncover that, although the online activity is increasing, the diversity in the content and the number of participants are decreasing. Describing the organizational development of the local memory community, we argue that the growth into a self-organizing community is the cause of increasing activity and decreasing participation. This implies that the online community has become a small, empowered group, which at the same time has developed dis-empowering characteristics, i.e. limitations to include ‘other’ locals, neighbourhoods and topics. We illustrate how the current self-organization, unintentionally, fuels the decreasing diversity in content by a natural selection process of a rather homogeneous group of participants. In addition, the conviction of what constitutes a successful online community is discussed for emphasizing individual empowerment and attracting empowered locals instead of vulnerable ones

EP-DRAFT-1.1 2014-01-19 OSI-GAM-SOP-00x In Situ High-resolution Gamma Spectroscopy

Abstract not provide

Hypothalamic‐specific proopiomelanocortin deficiency reduces alcohol drinking in male and female mice

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136536/1/gbb12362_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136536/2/gbb12362.pd

The discriminative effects of the κ-opioid hallucinogen salvinorin A in nonhuman primates: dissociation from classic hallucinogen effects

RATIONALE: The widely available hallucinogen salvinorin A is a unique example of a plant-derived compound selective for κ-opioid receptors and may produce effects distinct from those of other compounds with classic hallucinogenic or dissociative properties which are also abused in humans. OBJECTIVES: The objective of this study is to characterize the salvinorin A discriminative cue in nonhuman primates with high κ-receptor genetic homology to humans. METHODS: Adult rhesus monkeys (n=3) were trained to discriminate salvinorin A (0.015 mg/kg, s.c.) from vehicle, in a food-reinforced operant discrimination assay. Parallel studies, using unconditioned behavioral endpoints (facial relaxation and ptosis) also evaluated the κ-opioid receptor mediation of salvinorin A in vivo function. RESULTS: Monkeys trained to discriminate salvinorin A generalized structurally diverse, centrally penetrating κ-agonists (bremazocine, U69,593, and U50,488). By contrast, μ- and δ-opioid agonists (fentanyl and SNC80, respectively) were not generalized, nor were the serotonergic 5HT2 hallucinogen psilocybin or the dissociative N-methyl-D-aspartic acid antagonist, ketamine. The discriminative effects of salvinorin A were blocked by the opioid antagonist quadazocine (0.32 mg/kg), but not by the 5HT2 antagonist ketanserin (0.1 mg/kg). Consistent with these findings, salvinorin and κ-agonists (e.g., U69,593) produce effects in the unconditioned endpoints (e.g., ptosis), whereas psilocybin was inactive. Conclusions: These findings support the conclusion that the interoceptive/discriminative cue produced by salvinorin A is mediated by agonism at κ-receptors and is mechanistically distinct from that produced by a classic serotonergic hallucinogen

V1b Receptor Antagonist SSR149415 and Naltrexone Synergistically Decrease Excessive Alcohol Drinking in Male and Female Mice

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141424/1/acer13544.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141424/2/acer13544_am.pd