6-thioguanine treatment in inflammatory bowel disease: A critical appraisal by a European 6-TG working party

Recently, the suggestion to use 6-thioguanine (6-TG) as an alternative thiopurine in patients with inflammatory bowel disease (IBD) has been discarded due to reports about possible (hepato) toxicity. During meetings arranged in Vienna and Prague in 2004, European experts applying 6-TG further on in IBD patients presented data on safety and efficacy of 6-TG. After thorough evaluation of its risk-benefit ratio, the group consented that 6-TG may still be considered as a rescue drug in stringently defined indications in IBD, albeit restricted to a clinical research setting. As a potential indication for administering 6-TG, we delineated the requirement for maintenance therapy as well as intolerance and/or resistance to aminosalicylates, azathioprine, 6-mercaptopurine, methotrexate and infliximab. Furthermore, indications are preferred in which surgery is thought to be inappropriate. The standard 6-TG dosage should not exceed 25 mg daily. Routine laboratory controls are mandatory in short intervals. Liver biopsies should be performed after 6-12 months, three years and then three-yearly accompanied by gastroduodenoscopy, to monitor for potential hepatotoxicity, including nodular regenerative hyperplasia (NRH) and veno-occlusive disease (VOD). Treatment with 6-TG must be discontinued in case of overt or histologically proven hepatotoxicity. Copyright (c) 2006 S. Karger AG, Basel

A measurement of the tau mass and the first CPT test with tau leptons

We measure the mass of the tau lepton to be 1775.1+-1.6(stat)+-1.0(syst.) MeV using tau pairs from Z0 decays. To test CPT invariance we compare the masses of the positively and negatively charged tau leptons. The relative mass difference is found to be smaller than 3.0 10^-3 at the 90% confidence level.Comment: 10 pages, 4 figures, Submitted to Phys. Letts.

First Measurement of Z/gamma* Production in Compton Scattering of Quasi-real Photons

We report the first observation of Z/gamma* production in Compton scattering of quasi-real photons. This is a subprocess of the reaction e+e- to e+e-Z/gamma*, where one of the final state electrons is undetected. Approximately 55 pb-1 of data collected in the year 1997 at an e+e- centre-of-mass energy of 183 GeV with the OPAL detector at LEP have been analysed. The Z/gamma* from Compton scattering has been detected in the hadronic decay channel. Within well defined kinematic bounds, we measure the product of cross-section and Z/gamma* branching ratio to hadrons to be (0.9+-0.3+-0.1) pb for events with a hadronic mass larger than 60 GeV, dominated by (e)eZ production. In the hadronic mass region between 5 GeV and 60 GeV, dominated by (e)egamma* production, this product is found to be (4.1+-1.6+-0.6) pb. Our results agree with the predictions of two Monte Carlo event generators, grc4f and PYTHIA.Comment: 18 pages, LaTeX, 5 eps figures included, submitted to Physics Letters

Measurement of the Michel Parameters in Leptonic Tau Decays

The Michel parameters of the leptonic tau decays are measured using the OPAL detector at LEP. The Michel parameters are extracted from the energy spectra of the charged decay leptons and from their energy-energy correlations. A new method involving a global likelihood fit of Monte Carlo generated events with complete detector simulation and background treatment has been applied to the data recorded at center-of-mass energies close to sqrt(s) = M(Z) corresponding to an integrated luminosity of 155 pb-1 during the years 1990 to 1995. If e-mu universality is assumed and inferring the tau polarization from neutral current data, the measured Michel parameters are extracted. Limits on non-standard coupling constants and on the masses of new gauge bosons are obtained. The results are in agreement with the V-A prediction of the Standard Model.Comment: 32 pages, LaTeX, 9 eps figures included, submitted to the European Physical Journal

A Measurement of the Product Branching Ratio f(b->Lambda_b).BR(Lambda_b->Lambda X) in Z0 Decays

The product branching ratio, f(b->Lambda_b).BR(Lambda_b->Lambda X), where Lambda_b denotes any weakly-decaying b-baryon, has been measured using the OPAL detector at LEP. Lambda_b are selected by the presence of energetic Lambda particles in bottom events tagged by the presence of displaced secondary vertices. A fit to the momenta of the Lambda particles separates signal from B meson and fragmentation backgrounds. The measured product branching ratio is f(b->Lambda_b).BR(Lambda_b->Lambda X) = (2.67+-0.38(stat)+0.67-0.60(sys))% Combined with a previous OPAL measurement, one obtains f(b->Lambda_b).BR(Lambda_b->Lambda X) = (3.50+-0.32(stat)+-0.35(sys))%.Comment: 16 pages, LaTeX, 3 eps figs included, submitted to the European Physical Journal

WW Production Cross Section and W Branching Fractions in e+e- Collisions at 189 GeV

From a data sample of 183 pb^-1 recorded at a center-of-mass energy of roots = 189 GeV with the OPAL detector at LEP, 3068 W-pair candidate events are selected. Assuming Standard Model W boson decay branching fractions, the W-pair production cross section is measured to be sigmaWW = 16.30 +- 0.34(stat.) +- 0.18(syst.) pb. When combined with previous OPAL measurements, the W boson branching fraction to hadrons is determined to be 68.32 +- 0.61(stat.) +- 0.28(syst.) % assuming lepton universality. These results are consistent with Standard Model expectations.Comment: 22 pages, 5 figures, submitted to Phys. Lett.

Brane World Dynamics and Conformal Bulk Fields

In the Randall-Sundrum scenario we investigate the dynamics of a spherically symmetric 3-brane world when matter fields are present in the bulk. To analyze the 5-dimensional Einstein equations we employ a global conformal transformation whose factor characterizes the $Z_2$ symmetric warp. We find a new set of exact dynamical collapse solutions which localize gravity in the vicinity of the brane for a stress-energy tensor of conformal weight -4 and a warp factor that depends only on the coordinate of the fifth dimension. Geometries which describe the dynamics of inhomogeneous dust and generalized dark radiation on the brane are shown to belong to this set. The conditions for singular or globally regular behavior and the static marginally bound limits are discussed for these examples. Also explicitly demonstrated is complete consistency with the effective point of view of a 4-dimensional observer who is confined to the brane and makes the same assumptions about the bulk degrees of freedom.Comment: 26 pages, latex, no figures. Minor revisions. Some references added. Revised version to appear in Phys. Rev.

Layered soils in the shallow subsurface (<6.0 m), North Sea; a data report

The Carbon Trust (2015) “Cable Burial Risk Assessment (CBRA) Methodology” document is widely used in the offshore subsea cable industry to define the cable burial Depth of Lowering (DoL). To-date, published work on anchor penetration depths has focused on single homogeneous soil units, offering limited information on the response of different soil layering combinations, and associated contrasting geotechnical properties between soil units. By interrogating >11,000 shallow cores from the entire UK North Sea area, we demonstrate that “layered” soil combinations (e.g., “sand over clay”) are statistically common across the North Sea study area. The results also highlight the importance of updating current CBRA approaches to include “layered” soils, and associated changes in geotechnical properties (e.g., strength and density) between single and layered soil units. In addition, we collated geotechnical data for input into physical and numerical modelling under-taken by the University of Dundee and Durham University respectively (see Sharif et al., 2023; Bird et al., 2023 a, b), to assess the implications for the current CBRA Methodology. Ultimately the goal is to create a new CPT-based tool for better constraining the DoL, as part of the EPSRC research grant “Offshore Cable Burial: How deep is deep enough?”

Measurement of the B0 Lifetime and Oscillation Frequency using B0->D*+l-v decays

The lifetime and oscillation frequency of the B0 meson has been measured using B0->D*+l-v decays recorded on the Z0 peak with the OPAL detector at LEP. The D*+ -> D0pi+ decays were reconstructed using an inclusive technique and the production flavour of the B0 mesons was determined using a combination of tags from the rest of the event. The results t_B0 = 1.541 +- 0.028 +- 0.023 ps, Dm_d = 0.497 +- 0.024 +- 0.025 ps-1 were obtained, where in each case the first error is statistical and the second systematic.Comment: 17 pages, 4 figures, submitted to Phys. Lett.

Optimizing Long-Term Outcomes and Avoiding Failure With the Fibula Intramedullary Nail

Objectives: To identify risk factors for fixation failure, report patient outcomes, and advise on modifications to the surgical technique for fibula nail stabilization of unstable ankle fractures.Design: Retrospective review.Setting: Academic orthopaedic trauma unit.Patients: All 342 patients were identified retrospectively from a prospectively collected single-center trauma database over a 9-year period.Intervention: Unstable ankle fractures managed surgically with a fibula nail.Main Outcome Measurements: The primary short-term outcome was failure, defined as any case that required revision surgery because of an inadequate mechanical construct. The mid-term outcomes included the Olerud–Molander Ankle Score and the Manchester–Oxford Foot Questionnaire.Results: Twenty failures occurred (6%), of which 7 (2%) were due to device failure and 13 (4%) due to surgeon error. Of the surgeon errors, 8 consisted of inappropriate weight-bearing after syndesmotic diastasis, and 5 were due to inadequate fracture reduction or poor nail placement. Proximal locking screw (PLS) pull-out was the cause of all device failures. Positioning the PLS &gt;20 mm above the plafond significantly increased failure risk (P = 0.003). At a mean follow-up of 5.1 years (range, 8 months–8 years) the median Olerud–Molander Ankle Score and Manchester–Oxford Foot Questionnaire were 80 (interquartile range, 45) and 10.94 (interquartile range, 44.00), respectively. Patient outcome was not negatively affected by the requirement for revision surgery.Conclusions: The fibula nail offers secure fixation and good patient-reported outcomes for unstable ankle fractures. Appropriate postoperative management and surgical technique, including careful placement of the PLS, is essential to minimize construct failure risk