Threshold Resummation Effects in the Associated Production of Chargino and Neutralino at Hadron Colliders

We investigate the QCD effects in the associated production of the chargino and the neutralino, $\tilde\chi^\pm_{1}$ and $\tilde\chi^0_{2}$, in the Minimal Supersymmetric Standard Model (MSSM) at both the Fermilab Tevatron and the CERN Large Hadron Collider (LHC). We include the next-to-leading order (NLO) QCD corrections (including supersymmetric QCD) and the threshold resummation effects. Our results show that, compared to the NLO predictions, the threshold resummation effects can increase the total cross sections by 3.6% and 3.9% for the associated production of $\tilde\chi^+_{1}\tilde\chi^0_{2}$ and $\tilde\chi^-_{1}\tilde\chi^0_{2}$ at the LHC, respectively, and by 4.7% for those of $\tilde\chi^\pm_{1}\tilde\chi^0_{2}$ at the Tevatron. In the invariant mass distributions the resummation effects are significant for large invariant mass. The threshold resummation reduces the dependence of the total cross sections at the LHC (Tevatron) on the renormalization/factorization scales to 5% (4%) from up to 7% (11%) at NLO.Comment: revised version with midifications, several references adde

Bark Beetle and Wood Borer Infestation in the Greater Yellowstone Area During Four Postfire Years

Extensive surveys of bark beetles and wood bores in the Greater Yellowstone area were conducted in 1991 through 1993. The study objectives were to determine the effect of delayed tree mortality following the 1988 fires on mosaics of fire-killed and green tree stands, the relationship between fire injury and subsequent infestation, and the effect of insect buildup in fire injured trees on infestation rates for uninjured trees. Surveys were conducted adjacent to roads, and plots wee selected randomly. In 1991, 321 plots were measured, 198 plots in 1992, and 127 plots in 1993. Insects killed 12.6 percent of the Douglas-fir, 17.9 percent of the lodgepole pine, 6.6 percent of the Engelmann spruce, 7.5 percent of the subalpine fire, and 2.8 percent of the whitebark pine. Delayed mortality attributed to fire injury accounted for more mortality than insects. Both types of mortality greatly altered the original fire-killed/green tree mosaics that were apparent immediately after the 1988 fires. Insect infestation was strongly and positively correlated with the percent of the basal circumference of the tree that was fire killed in the species, except in Engelmann spruce where infestation peaked in the middle fire-injury class. Infestation in Douglas-fir, lodgepole pine, and Engelmann spruce increased through 1992 then declined in 1993. Although it cannot be said with certainty that insects built up in fire-injured trees and then caused increased infestation of uninjured trees, the high level of infestation suggests this is the case

Differential regulation of ENA-78 and GCP-2 gene expression in human corneal keratocytes and epithelial

PURPOSE. To determine whether interleukin (IL)-1␣-and tumor necrosis factor (TNF)-␣-stimulated human corneal epithelial cells (HCECs) and human corneal keratocytes (HCKs) produce the ␣-chemokines epithelial cell-derived neutrophil attractant (ENA)-78 and granulocyte chemotactic protein (GCP)-2. METHODS. Cultures of HCECs and HCKs were stimulated with either human recombinant IL-1␣ or TNF-␣. At selected times after stimulation, culture supernatants were harvested and assayed for ENA-78 and GCP-2 by enzyme-linked immunosorbent assay. RNA was extracted from cell cultures to measure steady state levels of intracellular ENA-78 and GCP-2 pre-mRNA and mRNA by the reverse transcription-polymerase chain reaction. RESULTS. Exposure of HCECs to either IL-1␣ or TNF-␣ stimulated a more than 4.5-fold increase in ENA-78 RNA and protein synthesis without stimulating a significant increase in either GCP-2 RNA synthesis or protein production. Exposure of HCK to IL-1␣ stimulated a 10-fold increase in ENA-78 and GCP-2 RNA synthesis and a more than 300-fold increase in ENA-78 and GCP-2 protein production. In contrast, exposure of keratocytes to TNF-␣ significantly enhanced ENA-78 RNA synthesis, resulting in a more than 68-fold increase in ENA-78 protein synthesis without significantly enhancing either GCP-2 gene expression or protein secretion. CONCLUSIONS. ENA-78 gene expression is significantly enhanced in both HCECs and HCKs in response to either IL-1␣ or TNF-␣ stimulation. In contrast, GCP-2 synthesis is only inducible in IL-1␣-stimulated HCKs. The results suggest that GCP-2 gene expression is more tightly regulated in diseased or injured corneal tissue than is ENA-78 gene expression. (Invest Ophthalmol Vis Sci. 2003;44:3432-3437

Contamination of clinical specimens with MLV-encoding nucleic acids: implications for XMRV and other candidate human retroviruses

Efforts to assess the prevalence of xenotropic murine leukemia virus-related virus (XMRV) in patients with prostate cancer and chronic fatigue syndrome have relied heavily on PCR-based testing of clinical samples and have yielded widely divergent findings. This week in Retrovirology, reports from four independent research groups illustrate the extreme care needed to exclude DNA or RNA contamination in PCR analyses of XMRV. In addition, phylogenetic evidence suggesting that previously-published XMRV sequences originated from a commonly-used prostate carcinoma cell line (22Rv1) is presented. These findings raise important questions regarding the provenance of XMRV and its potential connection to human disease

Dissecting regulatory T cell expansion using polymer microparticles presenting defined ratios of self-antigen and regulatory cues

Biomaterials allow for the precision control over the combination and release of cargo needed to engineer cell outcomes. These capabilities are particularly attractive as new candidate therapies to treat autoimmune diseases, conditions where dysfunctional immune cells create pathogenic tissue environments during attack of self-molecules termed self-antigens. Here we extend past studies showing combinations of a small molecule immunomodulator co-delivered with self-antigen induces antigen-specific regulatory T cells. In particular, we sought to elucidate how different ratios of these components loaded in degradable polymer particles shape the antigen presenting cell (APC) -T cell interactions that drive differentiation of T cells toward either inflammatory or regulatory phenotypes. Using rapamycin (rapa) as a modulatory cue and myelin self-peptide (myelin oligodendrocyte glycoprotein- MOG) – self-antigen attacked during multiple sclerosis (MS), we integrate these components into polymer particles over a range of ratios and concentrations without altering the physicochemical properties of the particles. Using primary cell co-cultures, we show that while all ratios of rapa:MOG significantly decreased expression of co-stimulation molecules on dendritic cells (DCs), these levels were insensitive to the specific ratio. During co-culture with primary T cell receptor transgenic T cells, we demonstrate that the ratio of rapa:MOG controls the expansion and differentiation of these cells. In particular, at shorter time points, higher ratios induce regulatory T cells most efficiently, while at longer time points the processes are not sensitive to the specific ratio. We also found corresponding changes in gene expression and inflammatory cytokine secretion during these times. The in vitro results in this study contribute to in vitro regulatory T cell expansion techniques, as well as provide insight into future studies to explore other modulatory effects of rapa such as induction of maintenance or survival cues

Supersymmetric Electroweak Corrections to Single Top Quark Production at the Fermilab Tevatron

We have calculated the $O(\alpha_{ew} M_t^2/M_W^2)$ supersymmetric electroweak corrections to single top quark production via $q\bar q' \to t\bar b$ at the Fermilab Tevatron in the minimal supersymmetric model. The supersymmetric electroweak corrections to the cross section are a few percent for $tan \beta> 1$, and can exceed 10% for $tan\beta<1$. The combined effects of SUSY electroweak corrections and the Yukawa corrections can exceed 10% for favorable parameter values, which might be observable at a high-luminosity Tevatron.Comment: 13 pages, 4 figures available at reques

The effect of pure mitral regurgitation on mitral annular geometry and three-dimensional saddle shape

ObjectiveChronic ischemic mitral regurgitation is associated with mitral annular dilatation in the septal-lateral dimension and flattening of the annular 3-dimensional saddle shape. To examine whether these perturbations are caused by the ischemic insult, mitral regurgitation, or both, we investigated the effects of pure mitral regurgitation (low pressure volume overload) on annular geometry and shape.MethodsEight radiopaque markers were sutured evenly around the mitral annulus in sheep randomized to control (CTRL, n = 8) or experimental (HOLE, n = 12) groups. In HOLE, a 3.5- to 4.8-mm hole was punched in the posterior leaflet to generate pure mitral regurgitation. Four-dimensional marker coordinates were obtained radiographically 1 and 12 weeks postoperatively. Mitral annular area, annular septal-lateral and commissure–commissure dimensions, and annular height were calculated every 16.7 ms.ResultsMitral regurgitation grade was 0.4 ± 0.4 in CTRL and 3.0 ± 0.8 in HOLE (P < .001) at 12 weeks. End-diastolic left ventricular volume index was greater in HOLE at both 1 and 12 weeks; end-systolic volume index was larger in HOLE at 12 weeks. Mitral annular area increased in HOLE predominantly in the commissure–commissure dimension, with no difference in annular height between HOLE versus CTRL at 1 or 12 weeks, respectively.ConclusionIn contrast with annular septal-lateral dilatation and flattening of the annular saddle shape observed with chronic ischemic mitral regurgitation, pure mitral regurgitation was associated with commissure–commissure dimension annular dilatation and no change in annular shape. Thus, infarction is a more important determinant of septal-lateral dilatation and annular shape than mitral regurgitation, which reinforces the need for disease-specific designs of annuloplasty rings

Using a stakeholder-engaged, iterative, and systematic approach to adapting collaborative decision skills training for implementation in VA psychosocial rehabilitation and recovery centers

Background: Adaptation of interventions is inevitable during translation to new populations or settings. Systematic approach to adaptation can ensure that fidelity to core functions of the intervention are preserved while optimizing implementation feasibility and effectiveness for the local context. In this study, we used an iterative, mixed methods, and stakeholder-engaged process to systematically adapt Collaborative Decision Skills Training for Veterans with psychosis currently participating in VA Psychosocial Rehabilitation and Recovery Centers. Methods: A modified approach to Intervention Mapping (IM-Adapt) guided the adaptation process. An Adaptation Resource Team of five Veterans, two VA clinicians, and four researchers was formed. The Adaptation Resource Team engaged in an iterative process of identifying and completing adaptations including individual qualitative interviews, group meetings, and post-meeting surveys. Qualitative interviews were analyzed using rapid matrix analysis. We used the modified, RE-AIM enriched expanded Framework for Reporting Adaptations and Modifications to Evidence-based interventions (FRAME) to document adaptations. Additional constructs included adaptation size and scope; implementation of planned adaptation (yes–no); rationale for non-implementation; and tailoring of adaptation for a specific population (e.g., Veterans). Results: Rapid matrix analysis of individual qualitative interviews resulted in 510 qualitative codes. Veterans and clinicians reported that the intervention was a generally good ft for VA Psychosocial Rehabilitation and Recovery Centers and for Veterans. Following group meetings to reach adaptation consensus, 158 adaptations were completed. Most commonly, adaptations added or extended a component; were small in size and scope; intended to improve the effectiveness of the intervention, and based on experience as a patient or working with patients. Few adaptations were targeted towards a specific group, including Veterans. Veteran and clinician stakeholders reported that these adaptations were important and would benefit Veterans, and that they felt heard and understood during the adaptation process. Conclusions: A stakeholder-engaged, iterative, and mixed methods approach was successful for adapting Collaborative Decision Skills Training for immediate clinical application to Veterans in a psychosocial rehabilitation center. The ongoing interactions among multiple stakeholders resulted in high quality, tailored adaptations which are likely to be generalizable to other populations or settings. We recommend the use of this stakeholder-engaged, iterative approach to guide adaptations

Vector and pseudoscalar charm meson radiative decays

Combining heavy quark effective theory and the chiral Lagrangian approach we investigate radiative decays of pseudoscalar $D$ mesons. We first reanalyse $D^{*} \rightarrow D \gamma$ decays within the effective Lagrangian approach using heavy quark spin symmetry, chiral symmetry Lagrangian, but including also the light vector mesons. We then investigate $D \rightarrow V \gamma$ decays and calculate the $D^0 \rightarrow \bar{K}^{*0} \gamma$ and $D^{s+} \rightarrow \rho^+ \gamma$ partial widths and branching ratios.Comment: 21 pages Latex, no figures, IJS-TP-94/19, TUM-31-62/94, NUHEP-TH-94-

Supersymmetric Electroweak Corrections to Charged Higgs Boson Production in Association with a Top Quark at Hadron Colliders

We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew} m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the cross section for the charged Higgs boson production in association with a top quark at the Tevatron and the LHC. These corrections arise from the quantum effects which are induced by potentially large Yukawa couplings from the Higgs sector and the chargino-top(bottom)-sbottom(stop) couplings, neutralino-top(bottom)-stop(sbottom) couplings and charged Higgs-stop-sbottom couplings. They can decrease or increase the cross section depending on $\tan\beta$ but are not very sensitive to the mass of the charged Higgs boson for high $\tan\beta$. At low $\tan\beta(=2)$ the corrections decrease the total cross sections significantly, which exceed -12% for $m_{H^{\pm}}$ below $300GeV$ at both the Tevatron and the LHC, but for $m_{H^{\pm}}>300GeV$ the corrections can become very small at the LHC. For high $\tan\beta(=10,30)$ these corrections can decrease or increase the total cross sections, and the magnitude of the corrections are at most a few percent at both the Tevatron and the LHC.Comment: 28 pages including 4 eps figure