Measurement of the mass of the τ lepton

A data-driven energy scan in the immediate vicinity of the τ pair production threshold has been performed using the Beijing Spectrometer at the Beijing Electron-Positron Collider. Approximately 5 pb^(-1) of data, distributed over 12 scan points, have been collected. A previous mass value for the τ lepton, obtained using only the eμ final state, has been published. In this paper, the final BES result on the mass measurement is presented. The analysis is based on the combined data from the ee, eμ, eh, μμ, μh, and hh final states, where h denotes a charged π or K. A maximum likelihood fit to the τ pair production cross section data yields the value m_τ=1776.96_(-0.21)-0.17^(+0.18+0.25) MeV

Measurement of the mass of the τ lepton

The mass of the τ lepton has been measured at the Beijing Electron-Positron Collider using the Beijing Spectrometer. A search near threshold for e^+e^-→τ^+τ^- was performed. Candidate events were identified by requiring that one τ decay via τ→eνν¯, and the other via τ→μνν¯. The mass value, obtained from a fit to the energy dependence of the τ^+τ^- cross section, is m_τ=1776.9_(-0.5)^(+0.4)±0.2 MeV

Direct measurement of B(D_s^+ → φX^+)

The absolute inclusive branching fraction of D_s^+→φX^+ has been measured from data collected by the BES detector at a center-of-mass energy of 4.03 GeV, corresponding to an integrated luminosity of 22.3 pb^(-1). At this energy, direct pair production e^+e^-→D_s^+D_s^- has been observed. We have selected D_s candidate events by reconstructing five hadronic decay modes D_s^+→φπ^+, K^(0*)K^+, K^0K^+, f0^(π+) and K^0K^-π^+π^+ and have searched for inclusive φ’s in the recoiling D_s^-. We observed three recoiling φ’s in the 166.4 ± 31.8 D_s candidate events, which leads to the absolute branching fraction B(D_s^+→φX^+)=(17.8(-7.2 -6.3)^(+15.1+0.6)) % and B(D_s-6.3+→φπ-6.3+)=(3.6_(-1.6 -1.3)(^_3.1+0.4) %. [S0556-2821(97)02423-5

TWO CASES OF NON-ALCOHOLIC WERNICKE ENCEPHALOPATHY SUCCESSFULLY TREATED BY THIAMINE REPLACEMENT: DIAGNOSTIC AND THERAPEUTIC CONSIDERATIONS

Wernicke\u2019s encephalopathy (WE) is an acute neurologi- cal disorder, due to a lack of thiamin (vitamin B1) which is observed mainly in alcoholic patients. Unfortunately, the syn- drome is underestimated in clinical practice and most often recognized only on autopsy, especially among non-alcoholics. The common clinical picture include mental status changes, ocular dysfunction, and gait ataxia. Treatment consists of timely thiamine replacement through intravenous infusion. We describe the case of two patients who developed a non-alcoholic WE post-surgical, regressed completely after intravenous infusion of thiamine. These cases suggest intere- sting diagnostic and therapeutic implications

Expression of telomeric repeat binding factor-1 in astroglial brain tumors

OBJECTIVE: In human somatic cells, telomeres shorten with successive cell divisions, resulting in progressive genomic instability, altered gene expression, and cell death. Recently, telomere-specific deoxyribonucleic acid-binding proteins, such as telomeric repeat binding factor-1 (TRF1), have been proposed as candidates for the role of molecules regulating telomerase activity, and they have been suggested to play key roles in the maintenance of telomere function. The present study was designed to assess TRF1 expression in human astroglial brain tumors and to speculate on the clinical implications of its expression. METHODS: Twenty flash-frozen surgical specimens obtained from adult patients who underwent craniotomy for microsurgical tumor resection, histologically verified as World Health Organization Grade II to IV astrocytomas, were used. Expression of TRF1 in astrocytomas of different grades was studied by means of both immunohistochemical and Western blotting analysis. The correlation between the extent of TRF1 expression and histological grading, performance status, and length of survival of patients underwent statistical analyses. RESULTS: TRF1 was expressed in all tumor samples. The level of its expression was variable, decreasing from low-grade through high-grade astrocytomas (P 0.0032). TRF1 expression correlated with the patient’s length of survival (P 0.001) and performance status (P 0.001) and proved to be an independent indicator of length of survival. CONCLUSION: Our findings suggest that the loss of TRF1 expression capability, as a result of down-regulation of TRF1 expression in malignant gliomas cells, may play a role in the malignant progression of astroglial brain tumors

The Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS) ? Part 1: Model description and evaluation

International audienceWe introduce the Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS). CATT-BRAMS is an on-line transport model fully consistent with the simulated atmospheric dynamics. Emission sources from biomass burning and urban-industrial-vehicular activities for trace gases and aerosol particles are obtained from several published datasets and remote sensing information. The tracer and aerosol mass concentration prognostic includes the effects of sub-grid scale turbulence in the planetary boundary layer, convective transport by shallow and deep moist convection, wet and dry deposition, and plume rise associated with vegetation fires in addition to the grid scale transport. The radiation parameterization takes into account the interaction between aerosol particles and short and long wave radiation. The atmospheric model BRAMS is based on the Regional Atmospheric Modeling System (RAMS), with several improvements associated with cumulus convection representation, soil moisture initialization and surface scheme tuned for the tropics, among others. In this paper the CATT-BRAMS model is used to simulate carbon monoxide and particulate material (PM2.5) surface fluxes and atmospheric transport during the 2002 LBA field campaigns, conducted during the transition from the dry to wet season in the southwest Amazon Basin. Model evaluation is addressed with comparisons between model results and near surface, radiosonde and airborne measurements performed during the field campaign, as well as remote sensing derived products. We show the matching of emissions strengths to observed carbon monoxide in the LBA campaign. A relatively good comparison to the MOPITT data, in spite of the fact that MOPITT a priori assumptions imply several difficulties, is also obtained