26 research outputs found

    Measurement of ZZ production in leptonic final states at {\surd}s of 1.96 TeV at CDF

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    In this paper we present a precise measurement of the total ZZ production cross section in pp collisions at {\surd}s= 1.96 TeV, using data collected with the CDF II detector corresponding to an integrated luminosity of approximately 6 fb-1. The result is obtained by combining separate measurements in the four-charged (lll'l'), and two-charged-lepton and two-neutral-lepton (llvv) decay modes of the Z. The combined measured cross section for pp {\to} ZZ is 1.64^(+0.44)_(-0.38) pb. This is the most precise measurement of the ZZ production cross section in 1.96 TeV pp collisions to date.Comment: submitted to Phys. Rev. Let

    Enhanced dust deposition by trees recently established on degraded rangeland

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    Results from 2 years of dust deposition monitoring in a 10-year-old Pinus nigra plantation near Lake Tekapo are presented. They show that recently established plantations significantly enhance dust deposition rates. This could reverse a cycle of soil loss and enhance vertical accretion of soil, which would provide more options for future land use. However, observations indicate that even under such enhanced conditions for soil formation, it would take several thousand years to replace the soil lost to erosion since European farming practices were first introduced to the northern section of the Mackenzie Basin

    Cost-effectiveness analysis of breast cancer control interventions in peru

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    Contains fulltext : 125263.pdf (publisher's version ) (Open Access)OBJECTIVES: In Peru, a country with constrained health resources, breast cancer control is characterized by late stage treatment and poor survival. To support breast cancer control in Peru, this study aims to determine the cost-effectiveness of different breast cancer control interventions relevant for the Peruvian context. METHODS: We performed a cost-effectiveness analysis (CEA) according to WHO-CHOICE guidelines, from a healthcare perspective. Different screening, early detection, palliative, and treatment interventions were evaluated using mathematical modeling. Effectiveness estimates were based on observational studies, modeling, and on information from Instituto Nacional de Enfermedades Neoplasicas (INEN). Resource utilizations and unit costs were based on estimates from INEN and observational studies. Cost-effectiveness estimates are in 2012 United States dollars (US)perdisabilityadjustedlifeyear(DALY)averted.RESULTS:ThecurrentbreastcancerprograminPeru() per disability adjusted life year (DALY) averted. RESULTS: The current breast cancer program in Peru (8,426 per DALY averted) could be improved through implementing triennial or biennial screening strategies. These strategies seem the most cost-effective in Peru, particularly when mobile mammography is applied (from 4,125perDALYaverted),orwhenbothCBEscreeningandmammographyscreeningarecombined(from4,125 per DALY averted), or when both CBE screening and mammography screening are combined (from 4,239 per DALY averted). Triennially, these interventions costs between 63millionand63 million and 72 million per year. Late stage treatment, trastuzumab therapy and annual screening strategies are the least cost-effective. CONCLUSIONS: Our analysis suggests that breast cancer control in Peru should be oriented towards early detection through combining fixed and mobile mammography screening (age 45-69) triennially. However, a phased introduction of triennial CBE screening (age 40-69) with upfront FNA in non-urban settings, and both CBE (age 40-49) and fixed mammography screening (age 50-69) in urban settings, seems a more feasible option and is also cost-effective. The implementation of this intervention is only meaningful if awareness raising, diagnostic, referral, treatment and basic palliative services are simultaneously improved, and if financial and organizational barriers to these services are reduced

    Measurement of the diffractive cross-section in deep inelastic scattering

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    Diffractive scattering of γpX+N\gamma^* p \to X + N, where NN is either a proton or a nucleonic system with MN < 4M_N~<~4~GeV has been measured in deep inelastic scattering (DIS) at HERA. The cross section was determined by a novel method as a function of the γp\gamma^* p c.m. energy WW between 60 and 245~GeV and of the mass MXM_X of the system XX up to 15~GeV at average Q2Q^2 values of 14 and 31~GeV2^2. The diffractive cross section dσdiff/dMXd\sigma^{diff} /dM_X is, within errors, found to rise linearly with WW. Parameterizing the WW dependence by the form d\sigma^{diff}/dM_X \propto (W^2)^{(2\overline{\mbox{\alpha_{_{I\hspace{-0.2em}P}}}} -2)} the DIS data yield for the pomeron trajectory \overline{\mbox{\alpha_{_{I\hspace{-0.2em}P}}}} = 1.23 \pm 0.02(stat) \pm 0.04 (syst) averaged over tt in the measured kinematic range assuming the longitudinal photon contribution to be zero. This value for the pomeron trajectory is substantially larger than \overline{\mbox{\alpha_{_{I\hspace{-0.2em}P}}}} extracted from soft interactions. The value of \overline{\mbox{\alpha_{_{I\hspace{-0.2em}P}}}} measured in this analysis suggests that a substantial part of the diffractive DIS cross section originates from processes which can be described by perturbative QCD. From the measured diffractive cross sections the diffractive structure function of the proton F^{D(3)}_2(\beta,Q^2, \mbox{x_{_{I\hspace{-0.2em}P}}}) has been determined, where β\beta is the momentum fraction of the struck quark in the pomeron. The form F^{D(3)}_2 = constant \cdot (1/ \mbox{x_{_{I\hspace{-0.2em}P}}})^a gives a good fit to the data in all β\beta and Q2Q^2 intervals with $a = 1.46 \pm 0.04 (stat) \pmComment: 45 pages, including 16 figure
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