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Usual Way (usual + way)
Selected AbstractsAspects of stability and phenomenology in type IIA orientifolds with intersecting D6-branesFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 1 2004T. OttArticle first published online: 14 JAN 200 Abstract Intersecting branes have been the subject of an elaborate string model building for several years. After a general introduction into string theory, this work introduces in detail the toroidal and -orientifolds. The picture involving D9-branes with B-fluxes is shortly reviewed, but the main discussion employs the T-dual picture of intersecting D6-branes. The derivation of the R-R and NS-NS tadpole cancellation conditions in the conformal field theory is shown in great detail. Various aspects of the open and closed chiral and non-chiral massless spectrum are discussed, involving spacetime anomalies and the generalized Green-Schwarz mechanism. An introduction into possible gauge breaking mechanisms is given, too. Afterwards, both ,, = 1 supersymmetric and non-supersymmetric approaches to low energy model building are treated. Firstly, the problem of complex structure instabilities in toroidal ,R -orientifolds is approached by a -orbifolded model. In particular, a stable non-supersymmetric standard-like model with three fermion generations is discussed. This model features the standard model gauge groups at the same time as having a massless hypercharge, but possessing an additional global B - L symmetry. The electroweak Higgs mechanism and the Yukawa couplings are not realized in the usual way. It is shown that this model descends naturally from a flipped SU(5) GUT model, where the string scale has to be at least of the order of the GUT scale. Secondly, supersymmetric models on the -orbifold are discussed, involving exceptional 3-cycles and the explicit construction of fractional D-branes. A three generation Pati-Salam model is constructed as a particular example, where several brane recombination mechanisms are used, yielding non-flat and non-factorizable branes. This model even can be broken down to a MSSM-like model with a massless hypercharge. Finally, the possibility that unstable closed and open string moduli could have played the role of the inflaton in the evolution of the universe is being explored. In the closed string sector, the important slow-rolling requirement can only be fulfilled for very specific cases, where some moduli are frozen and a special choice of coordinates is taken. In the open string sector, inflation does not seem to be possible at all. [source] A COMPARISON OF THE DISCRIMINATING POWER OF ANOVA AND R-INDEX ANALYSES OF HEDONIC DATA FOR VARIOUS PRODUCTS AND EXPERIMENTAL PROTOCOLSJOURNAL OF SENSORY STUDIES, Issue 3 2007HAENA PARK ABSTRACT Consumers rated a set of toothpastes and a set of orange-flavored beverages on a 9-point hedonic scale, using two experimental protocols: Rank-Rating where stimuli could continually be reassessed and a more traditional approach where they could not. A 21-point hedonic scale was also used in the Rank-Rating condition. The hedonic data were analyzed in the usual way using ANOVA with multiple comparisons and also by ranking the data and using an R-index analysis. Regarding the numbers of significant differences recorded, the two analyses were comparable, with a very slight and nonsignificant advantage for the ANOVA analysis. Unlike with intensity scaling, the difference between Rank-Rating and "traditional" scaling was slight but not for all products. The same was true for scale length effects. Differences among the products suggested effects due to the number of attributes that varied. PRACTICAL APPLICATIONS The key finding in this study is the use of Rank-Rating where stimuli could continually be re-assessed for the assessment of hedonic response of consumers in the various products. Rank-Rating may possibly give a better discrimination than more traditional scaling, depending on the number of attributes which varied. The results of the study also recommend the use of R-index analyses of ranked hedonic data in the analyses rather than ANOVA with multiple comparisons. [source] Observations of downslope winds and rotors in the Falkland IslandsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 605 2005S. D. Mobbs Abstract A field campaign aimed at observing the near-surface flow field across and downwind of a mountain range on the Falkland Islands, South Atlantic, is described. The objective was to understand and eventually predict orographically generated turbulence. The instrumentation was based primarily on an array of automatic weather stations (AWSs), which recorded 30 s mean surface pressure, wind speed and direction (at 2 m), temperature and relative humidity for approximately one year. These measurements were supported by twice-daily radiosonde releases. The densest part of the AWS array was located to the south of the Wickham mountain range, across Mount Pleasant Airfield (MPA). In northerly flow the array provides a detailed study of the flow downwind of the mountain range. The dataset contains several episodes in which the flow downwind of the mountains is accelerated relative to the upwind flow. During some of these episodes short-lived (typically ,1 hour) periods of unsteady flow separation are observed and these are associated with the formation of rotors aloft. Such events present a significant hazard to aviation at MPA. Examination of radiosonde profiles suggests that the presence of a strong temperature inversion at a height similar to the mountain height is a necessary condition for both downwind acceleration and the formation of rotors. The data are used to show that the downwind fractional speed-up is proportional to the non-dimensional mountain height (based on upstream near-surface winds and a depth-averaged Brunt,Väisälä frequency diagnosed from radiosonde data). Similarly, a relationship is established between a quantity that describes the spatial variability of the flow downwind of the mountains and the upstream wind and depth-averaged Brunt,Väisälä frequency. The dependence of the flow behaviour on the Froude number (defined in the usual way for two-layer shallow-water flow) and ratio of mountain height to inversion height is presented in terms of a flow regime diagram. © Royal Meteorological Society, 2005. S. B. Vosper's and P. F. Sheridan's contributions are Crown copyright [source] Octahedral tilting in cation-ordered Jahn,Teller distorted perovskites , a group-theoretical analysisACTA CRYSTALLOGRAPHICA SECTION B, Issue 1 2010Christopher J. Howard Computer-based group-theoretical methods are used to enumerate structures arising in A2BB,X6 perovskites, with either rock-salt or checkerboard ordering of the B and B, cations, under the additional assumption that one of these two cations is Jahn,Teller active and thereby induces a distortion of the BX6 (or B,X6) octahedron. The requirement to match the pattern of Jahn,Teller distortions to the cation ordering implies that the corresponding irreducible representations should be associated with the same point in the Brillouin zone. Effects of BX6 (and B,X6) octahedral tilting are included in the usual way. Finally, an analysis is presented of more complex models of ordering and distortion as might lead to the doubling of the long axis of the common Pnma perovskite, observed in systems such as Pr1,,,xCaxMnO3 (x, 0.5). The structural hierarchies derived in this work should prove useful in interpreting experimental results. [source] The choice of timing for diuresis renography:the F+0 methodBJU INTERNATIONAL, Issue 1 2001A.A.B. Adeyoju Objective To investigate a method of diuresis renography where the radiopharmaceutical and frusemide (diuretic) are given simultaneously, in contrast to conventional renography which involves an intravenous injection with frusemide 20 min after administering the radiopharmaceutical (F+20) or 15 min before (F,15), with particular interest in the effect of this change on assessing split renal function and interpreting upper tract drainage dynamics. Patients and methods In a prospective study, 29 patients (18 women and 11 men, mean age 47 years, range 21,86) were assessed. Each patient had two renograms taken over a 48-h period, either by the F+20 or F,15, and the F+0 method. Data for split renal function and drainage curves were obtained in the usual way. Two independent assessments of the drainage curves were obtained and the results compared. Results The split function assessments were identical (<5% variation) in all but two patients; 26 of 29 (90%) gave identical conclusions about the drainage curves. The three patients with discrepancies between the studies had either hugely dilated upper tracts or otherwise had multiple complicating factors, e.g. impaired renal function, neuropathic bladder. Conclusions F+0 renography has been used in paediatric urological practice before, but there are no comparative studies and no data on its use in adults. This prospective study confirmed that in investigating dilated upper tracts, the F+0 technique gives similar results to the conventional techniques. The F+0 method has the potential to reduce the time required to undertake standard F+20 renography but it may not be useful in evaluating the grossly dilated upper tract, where the F,15 technique has the best record in terms of reducing equivocal results. [source] Emotions in Solution-Focused Therapy: A Re-examinationFAMILY PROCESS, Issue 1 2000Gale Miller Ph.D. This article re-examines whether and how emotions are an aspect of solution-focused therapy. A major theme in the article focuses on the usual ways that therapists define and discuss emotions in solution-focused and other therapies. We argue that these discussions are a source of much confusion about emotions and about solution-focused therapy, including the confusing idea that emotions are neglected in solution-focused therapy. The second major theme describes an alternative approach to these issues, one that we believe better fits with the assumptions and concerns of solution-focused therapy. The approach is based on Wittgenstein's writings about language games, private experience, and how emotions are rule-following activities. Viewed from this perspective, solution-focused therapists take account of their clients' emotions by helping clients to create new emotion rules to follow. [source] | ||||||||||