Evidence of Color Coherence Effects in W+jets Events from ppbar Collisions at sqrt(s) = 1.8 TeV

We report the results of a study of color coherence effects in ppbar collisions based on data collected by the D0 detector during the 1994-1995 run of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8 TeV. Initial-to-final state color interference effects are studied by examining particle distribution patterns in events with a W boson and at least one jet. The data are compared to Monte Carlo simulations with different color coherence implementations and to an analytic modified-leading-logarithm perturbative calculation based on the local parton-hadron duality hypothesis.Comment: 13 pages, 6 figures. Submitted to Physics Letters

Search for electroweak production of single top quarks in ppˉp\bar{p} collisions.

We present a search for electroweak production of single top quarks in the electron+jets and muon+jets decay channels. The measurements use ~90 pb^-1 of data from Run 1 of the Fermilab Tevatron collider, collected at 1.8 TeV with the DZero detector between 1992 and 1995. We use events that include a tagging muon, implying the presence of a b jet, to set an upper limit at the 95% confidence level on the cross section for the s-channel process ppbar->tb+X of 39 pb. The upper limit for the t-channel process ppbar->tqb+X is 58 pb. (arXiv

Hard Single Diffraction in pbarp Collisions at root-s = 630 and 1800 GeV

Using the D0 detector, we have studied events produced in proton-antiproton collisions that contain large forward regions with very little energy deposition (``rapidity gaps'') and concurrent jet production at center-of-mass energies of root-s = 630 and 1800 Gev. The fractions of forward and central jet events associated with such rapidity gaps are measured and compared to predictions from Monte Carlo models. For hard diffractive candidate events, we use the calorimeter to extract the fractional momentum loss of the scattered protons.Comment: 11 pages 4 figures. submitted to PR

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Protocol in managing oral surgical patients taking dabigatran

New anticoagulants are being introduced into the market. These drugs are orally administered, have predictable pharmacokinetics and dose response, do not require monitoring and have an acceptable safety profile when used appropriately, and so avoid many of the disadvantages and possible complications of warfarin and heparin. Dabigatran is the most widely used, and has been approved by the Therapeutic Goods Administration. The use of dabigatran will likely increase in the coming years, and so it is important for dentists to be aware of its mechanism of action, the possible complications, and how to reverse the bleeding if it occurs. This review discusses dabigatran and reports on our experience of five cases, and provides practical clinical advice on how to manage patients on dabigatran who require dental treatment, particularly extractions.O Breik, A Cheng, PJ Sambrook, AN Gos

Lack of cytomegalovirus infection after pancreatic islet transplantation

Background. Cytomegalovirus (CMV) infection in the immunosuppressed transplant recipient is a cause of significant morbidity. With ganciclovir prophylaxis, the overall incidence of CMV after simultaneous kidney-whole pancreas transplantation remains as high as 40%, while CMV infection has never been reported following pancreatic islet transplantation (PIT) alone (i.e., without kidney transplantation). We designed the following study to objectively quantify the rate of transmission of CMV after clinical PIT. Methods. The 26 pancreatic islet grafts used at our institution since 1/2001 and the corresponding 11 PIT recipients were studied. The CMV serology of all organ donors was tested using a latex agglutination assay for anti-CMV antibody (CMV Scan™, Becton Dickinson®, Cockeysville, MD), a test capable of detecting one CMV-infected cell per 50,000 cells. Following PIT, recipients were closely monitored for clinical symptoms consistent with CMV infection. All patients were tested monthly for the presence of CMV antigenemia using immunofluorescent monoclonal antibodies for the CMV pp65 antigen (Light Diagnostics™, Chemicon®, Temecula, CA). All patients received valganciclovir 450 mg PO BID for 3 months following each PIT. Immunosuppression consisted of daclizumab, sirolimus, and tacrolimus. Results. Eight of the PIT recipients (72%) were CMV seronegative prior to PIT (R−). Eighteen of the 26 pancreatic islet grafts (69%) were from CMV+ donors (D+), and the remaining eight (31%) were from CMV− donors (D−). A single R− recipient received only D− pancreatic islets, while the remaining seven received at least one D+ pancreatic islets graft. In all there were 6 D+R+, 3 D−R+, 12 D+R−, and 5 D−R− PITs. No patient developed symptoms consistent with CMV infection at any time following PIT. Monthly routine blood testing of all recipients has revealed no detectable CMV antigenemia in any patient. Conclusion. In our series neither CMV transmission nor CMV infection was seen after PIT. The risk of CMV transmission is lower after PIT than the risk after simultaneous kidney--pancreas transplantation