One-loop QCD interconnection effects in pair production of top quarks

We calculate the one-loop non-factorizable QCD corrections to the production and decay of pairs of top quarks at various collider experiments. These non-factorizable corrections interconnect the different production and decay stages of the off-shell top-pair production processes. This in particular affects the invariant-mass distributions of the off-shell top quarks, resulting in a shift of the maximum of the distorted Breit-Wigner distributions. Although the non-factorizable corrections can be large, the actual shift in the mass as determined from the peak position of the corrected Breit-Wigner line-shape is below 100\MeV.Comment: 11 pages, LaTeX2e (uses axodraw.sty), 2 ps figures included; some numerical results changed, reference adde

Olfactory dysfunction in patients with primary progressive MS

OBJECTIVE: We tested the hypothesis that olfactory function is more impaired in patients with primary progressive MS (PPMS) than that in relapsing-remitting MS (RRMS). METHODS: Standardized olfactory testing was performed in 32 patients with PPMS, 32 patients with RRMS, and 32 healthy controls (HCs). Patients with olfactory dysfunction due to an alternative primary etiology were excluded. The validated olfactory testing method yielded individual scores for olfactory threshold, odor discrimination, and odor identification, along with a composite Threshold Discrimination Identification (TDI) score. RESULTS: Olfactory dysfunction was identified in 27 (84%) patients with PPMS, 10 (31%) patients with RRMS, and 1 (3%) HC. While age and sex were similar between PPMS and HCs, the TDI score and all olfactory subscores were significantly worse in patients with PPMS compared with HCs (all p < 0.001). After adjustment for differences in age, sex, Expanded Disability Status Scale (EDSS), and disease duration, odor discrimination, odor identification, and the composite TDI score were worse in patients with PPMS vs RRMS (p = 0.03, 0.04, and 0.02, respectively). Neither age, sex, EDSS, nor disease duration was significantly associated with the composite TDI score. CONCLUSIONS: Olfactory dysfunction was more frequent and severe in PPMS compared with RRMS, independent of disease duration and overall disability status. Further research on cellular level differences in olfactory neural pathways may lead to new insights about disease pathogenesis in MS

Olfactory and gustatory dysfunction in patients with autoimmune encephalitis

OBJECTIVE: To test the hypothesis that olfactory (OF) and gustatory function (GF) is disturbed in patients with autoimmune encephalitides (AE). METHODS: The orthonasal OF was tested in 32 patients with AE and 32 age- and sex-matched healthy controls (HC) with the standardized Threshold Discrimination Identification (TDI) score. This validated olfactory testing method yields individual scores for olfactory threshold (T), odor discrimination (D), and identification (I), along with a composite TDI score. The GF was determined by the Taste Strip Test (TST). RESULTS: Overall, 24/32 (75%) of patients with AE, but none of 32 HC (p < 0.001) had olfactory dysfunction in TDI testing. The results of the threshold, discrimination and identification subtests were significantly reduced in patients with AE compared to HC (all p < 0.001). Assessed by TST, 5/19 (26.3%) of patients with AE, but none of 19 HC presented a significant limitation in GF (p < 0.001). The TDI score was correlated with the subjective estimation of the olfactory capacity on a visual analog scale (VAS; r(s) = 0.475, p = 0.008). Neither age, sex, modified Rankin Scale nor disease duration were associated with the composite TDI score. CONCLUSIONS: This is the first study investigating OF and GF in AE patients. According to unblinded assessment, patients with AE have a reduced olfactory and gustatory capacity compared to HC, suggesting that olfactory and gustatory dysfunction are hitherto unrecognized symptoms in AE. Further studies with larger number of AE patients would be of interest to verify our results

Controlling colloidal sedimentation using time dependent shear

Employing a recently developed dynamical density functional theory we study the response of a colloidal sediment above a wall to shear, demonstrating the time dependent changes of the density distribution and its center-of-mass after switching shear either on or off and under oscillatory shear. Following the onset of steady shear we identify two dynamical mechanisms, distinguished by their timescales. Shortly after the onset, a transient enhancement of the packing structure at the wall reflects the self-organization into lanes. On a much longer timescale these effects are transmitted to the bulk, leading to migration away from the wall and an increase in the center-of-mass. Under oscillatory shear flow the center-of-mass enters a stationary state, reminiscent of a driven damped oscillator.Comment: 6 pages, 4 figure

Relativistic ponderomotive force, uphill acceleration, and transition to chaos

Starting from a covariant cycle-averaged Lagrangian the relativistic oscillation center equation of motion of a point charge is deduced and analytical formulae for the ponderomotive force in a travelling wave of arbitrary strength are presented. It is further shown that the ponderomotive forces for transverse and longitudinal waves are different; in the latter, uphill acceleration can occur. In a standing wave there exists a threshold intensity above which, owing to transition to chaos, the secular motion can no longer be described by a regular ponderomotive force. PACS number(s): 52.20.Dq,05.45.+b,52.35.Mw,52.60.+hComment: 8 pages, RevTeX, 3 figures in PostScript, see also http://www.physik.th-darmstadt.de/tqe

QCD strings with spinning quarks

We construct a consistent action for a massive spinning quark on the end of a QCD string that leads to pure Thomas precession of the quark's spin. The string action is modified by the addition of Grassmann degrees of freedom to the string such that the equations of motion for the quark spin follow from boundary conditions, just as do those for the quark's position.Comment: REVTeX4, 10 pages, no figure

Mobile Service Clouds: A self-managing infrastructure for autonomic mobile computing services

Abstract. We recently introduced Service Clouds, a distributed infrastructure designed to facilitate rapid prototyping and deployment of autonomic communication services. In this paper, we propose a model that extends Service Clouds to the wireless edge of the Internet. This model, called Mobile Service Clouds, enables dynamic instantiation, composition, configuration, and reconfiguration of services on an overlay network to support mobile computing. We have implemented a prototype of this model and applied it to the problem of dynamically instantiating and migrating proxy services for mobile hosts. We conducted a case study involving data streaming across a combination of PlanetLab nodes, local proxies, and wireless hosts. Results are presented demonstrating the effectiveness of the prototype in establishing new proxies and migrating their functionality in response to node failures.

Upgrade of the Glasgow photon tagging spectrometer for Mainz MAMI-C

The Glasgow photon tagging spectrometer at Mainz has been upgraded so that it can be used with the 1500 MeV electron beam now available from the Mainz microtron MAMI-C. The changes made and the resulting properties of the spectrometer are discussed.Comment: 20 pages, 12 figure

Hyaluronan and Hyaluronidase, which is better for embryo development?

Our aim was to examine size-specific effects of Hyaluronan (HA) on preimplantation embryo development. We investigated the effects of Hyalovet (HA, 500–750 kDa; the size produced by HA synthase-3, which is abundant in the oviduct), or HA treated with Hyaluronidase-2 (Hyal2; also expressed in the oviduct that breaks down HA into 20 kDa fragments). In experiment 1 (in vivo), oviducts of synchronized and superovulated ewes (n = 20) were surgically exposed on Day 2 post-mating, ligated, and infused with either Hyalovet, Hyalovet + Hyal2, Hyal2, or PBS (control). Ewes were killed 5 days later for recovery of embryos and oviductal epithelial cells (OEC). Blastocyst rates were significantly higher in Hyal2 and Hyalovet + Hyal2 oviducts. Hyaluronidase-2 infusion resulted in higher blastocyst cell numbers and hatching rates. This was associated with increased HSP70 expression in OEC. In contrast, Hyalovet resulted in the lowest development to blastocyst stage and lowest hatching rates, and decreased IGF2 and IGFBP2 expression in OEC. IGF1 and IL1α expression were not affected. In experiment 2, to rule out indirect effects of oviductal factors, ovine embryos were produced and cultured with the same treatments in vitro from Day 2 to 8. Hyaluronidase-2, but not Hyalovet, enhanced blastocyst formation and reduced inner cell mass apoptosis. Hyalovet inhibited hatching. In conclusion, the presence of large-size HA (500–750 kDa) in the vicinity of developing embryos appears to disturb the oviductal environment and embryo development in vivo and in vitro. In contrast, we show evidence that breakdown of HA into smaller fragments is required to maximize embryo development and blastocyst quality