890 research outputs found

    Contemporary Occupational Carcinogen Exposure and Bladder Cancer: A Systematic Review and Meta-analysis

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    Importance: Bladder cancer (BC) is a common disease. Despite manufacturing and legislative changes to workplace hygiene, many BCs still arise through occupational carcinogen exposure. Objective: To profile contemporary risks of occupational BC. Data Sources: A systematic review using PubMed, Medline, Embase, and Web of Science was performed in October 2012 (initial review) and May 2014 (final review) and was updated in June 2015. Study Selection: We identified 263 eligible articles. We excluded reports in which BC or occupation were not the main focus, and those with insufficient case, risk, or confidence interval data. We selected the most recent data from populations with multiple reports. Data Extraction and Synthesis: Reports were selected by 2 of us independently. We combined odds ratios and risk ratios (RRs) to provide pooled RRs, using maximally adjusted RRs in a random effects model. Heterogeneity and publication bias were assessed using I2 and Begg and Egger tests. Risk estimates were annotated by occupational class using Nordisk Yrkesklassificering, or Nordic Occupational Classification, and International Standard Classifications of Occupations (NYK and ISCO-1958) Codes. Main Outcomes and Measures: Occupations were profiled by BC incidence and mortality risk over time. After data collection, we detected a sex difference in these profiles and recorded this as a secondary outcome. Results: Meta-analysis revealed increased BC incidence in 42 of 61 occupational classes and increased BC-specific mortality in 16 of 40 occupational classes. Reduced incidence and mortality were seen in 6 of 61 and 2 of 40 classes, respectively. Risk varied with sex and was greatest in men (standardized incidence ratio, 1.03 [95% CI, 1.02-1.03]; P < .001]). From the 1960s to the 1980s, there was a steady decline in standarized incidence ratio (SIR) for both sexes. This trend reversed from the 1980s, as in the decade 2000 to 2010 the SIR increased to 1.13 (95% CI, 1.07-1.19) for men and 1.27 (95% CI, 1.12-1.43) for women. In contrast, mortality risk declined for both sexes from the 1960s to the 1990s. The overall risk of BC mortality was also greater for men (standardized mortality ratio [SMR], 1.32 [95% CI, 1.18-1.48]) than for women (SMR, 1.14 [95% CI, 0.80-1.63]). Limitations include possible publication bias, that reports stratify workers mostly by job title not task, that not all studies adjusted for smoking, and that the population was mostly derived from Western nations. Conclusions and Relevance: The profile of contemporary occupations with increased BC risk is broad and differs for incidence and mortality. Currently the incidence seems to be increasing, and this increase is occurring faster in women than men. Improved detection mechanisms and screening are possible reasons for this. Workers with aromatic amine exposure have the highest incidence, while those exposed to polycyclic aromatic hydrocarbons and heavy metals have the greatest mortality

    Optimization of quasi-normal eigenvalues for Krein-Nudelman strings

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    The paper is devoted to optimization of resonances for Krein strings with total mass and statical moment constraints. The problem is to design for a given αR\alpha \in \R a string that has a resonance on the line \alpha + \i \R with a minimal possible modulus of the imaginary part. We find optimal resonances and strings explicitly.Comment: 9 pages, these results were extracted in a slightly modified form from the earlier e-print arXiv:1103.4117 [math.SP] following an advise of a journal's refere

    The non-forward BFKL amplitude and rapidity gap physics

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    We discuss the BFKL approach to processes with large momentum transferred through a rapidity gap. The Mueller and Tang scheme to the BFKL non-forward parton-parton elastic scattering amplitude at large tt, is extended to include higher conformal spins. The new contributions are found to decrease with increasing energy, as follows from the gluon reggeisation phenomenon, and to vanish for asymptotically high energies. However, at moderate energies and high t|t|, the higher conformal spins dominate the amplitude. We illustrate the effects by studying the production of two high ETE_T jets separated by a rapidity gap at HERA energies. In a simplified framework, we find excellent agreement with the HERA photoproduction data once we incorporate the rapidity gap survival probability against soft rescattering effects. We emphasize that measurements of the analogous process in electroproduction may probe different summations over conformal spins.Comment: Latex, 14 pages, 3 figures; the final version to appear in Phys. Lett. B; a short discussion of the Tevatron data added; a previously missing factor of i^n introduced in eq. (13

    Martingale optimal transport with stopping

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    We solve the martingale optimal transport problem for cost functionals represented by optimal stopping problems. The measure-valued martingale approach developed in ArXiv: 1507.02651 allows us to obtain an equivalent infinite-dimensional controller-stopper problem. We use the stochastic Perron's method and characterize the finite dimensional approximation as a viscosity solution to the corresponding HJB equation. It turns out that this solution is the concave envelope of the cost function with respect to the atoms of the terminal law. We demonstrate the results by finding explicit solutions for a class of cost functions.Comment: Final version. To appear in SIAM Journal on Control and Optimization. Keywords: nonlinear Martingale optimal transport, dynamic programming, optimal stopping, stochastic Perron's method, viscosity solutions, state constraints, exit time problem, concave envelope, distribution constraint

    Vegetation and floristics of a lowland tropical rainforest in northeast Australia

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    Background: Full floristic data, tree demography, and biomass estimates incorporating non-tree life forms are seldom collected and reported for forest plots in the tropics. Established research stations serve as important repositories of such biodiversity and ecological data. With a canopy crane setup within a tropical lowland rainforest estate, the 42-ha Daintree Rainforest Observatory (DRO) in Cape Tribulation, northern Australia is a research facility of international significance. We obtained an estimate of the vascular plant species richness for the site, by surveying all vascular plant species from various mature-phase, remnant and open vegetation patches within the site. We also integrate and report the demography and basal areas of trees ≥ 10 cm diameter at breast height (dbh) in a new 1- ha core plot, an extension to the pre-existing forest 1-ha plot under the canopy crane. In addition, we report for the canopy crane plot new demography and basal areas for smaller size shrubs and treelets subsampled from nine 20 m quadrats, and liana basal area and abundance from the whole plot. The DRO site has an estimated total vascular plant species richness of 441 species, of which 172 species (39%) are endemic to Australia, and 4 species are endemics to the Daintree region. The 2 x 1-ha plots contains a total of 262 vascular plant species of which 116 (1531 individuals) are tree species ≥ 10 cm dbh. We estimate a stem basal area of 34.9 m ha, of which small stems (tree saplings and shrubs <10cm dbh) and lianas collectively contribute c.4.2%. Comparing the stem density-diversity patterns of the DRO forest with other tropical rainforests globally, our meta-analysis shows that DRO forests has a comparatively high stem density and moderate species diversity, due to the influence of cyclones. These data will provide an important foundation for ecological and conservation studies in lowland tropical forest. New information: We present a floristic checklist, a life form breakdown, and demography data from two 1-ha rainforest plots from a lowland tropical rainforest study site. We also present a meta-analysis of stem densities and species diversity from comparable-sized plots across the tropics

    QED Effective Action at Finite Temperature: Two-Loop Dominance

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    We calculate the two-loop effective action of QED for arbitrary constant electromagnetic fields at finite temperature T in the limit of T much smaller than the electron mass. It is shown that in this regime the two-loop contribution always exceeds the influence of the one-loop part due to the thermal excitation of the internal photon. As an application, we study light propagation and photon splitting in the presence of a magnetic background field at low temperature. We furthermore discover a thermally induced contribution to pair production in electric fields.Comment: 34 pages, 4 figures, LaTe

    Questions of fairness and anti-doping in US cycling: The contrasting experiences of professionals and amateurs

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    The focus of researchers, media and policy on doping in cycling is often limited to the professional level of the sport. However, anti-doping test results since 2001 demonstrate that banned substances are also used by US cyclists at lower levels of the sport, necessitating a broader view of the patterns and motivations of substance use within the sport. In this article, we describe and explain the doping culture that has emerged in domestic US cycling among amateur and semi-professionals. Through analysis of records from sports governing bodies and journalistic reports, we assess the range of violation types and discuss the detection and punishing of riders who were not proven to have intended to cheat but became "collateral damage" in the war on doping. We argue that the phenomenon of doping is more complex than what has been shown to occur in elite sport, as it includes a wider variety of behaviours, situations and motivations. We develop fresh insights by examining cases where doping has been accidental, intrinsically motivated, non-performance enhancing or the result of prescribed medical treatments banned by anti-doping authorities. Such trends call into question the fairness of anti-doping measures, and we discuss the possibility of developing localised solutions to testing and sanctioning amateur athletes

    Forward Jets and Energy Flow in Hadronic Collisions

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    We observe that at the Large Hadron Collider, using forward + central detectors, it becomes possible for the first time to carry out calorimetric measurements of the transverse energy flow due to "minijets" accompanying production of two jets separated by a large rapidity interval. We present parton-shower calculations of energy flow observables in a high-energy factorized Monte Carlo framework, designed to take into account QCD logarithmic corrections both in the large rapidity interval and in the hard transverse momentum. Considering events with a forward and a central jet, we examine the energy flow in the interjet region and in the region away from the jets. We discuss the role of these observables to analyze multiple parton collision effects.Comment: 9 pages, 5 figures. Version2: added results on azimuthal distributions and more discussion of energy flow definition using jet clusterin

    A Measurement of the Branching Ratio of KLe+eγγK_L \to e^+e^-\gamma\gamma

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    We report on a study of the decay KLe+eγγK_L \to e^+e^-\gamma\gamma carried out as a part of the KTeV/E799 experiment at Fermilab. The 1997 data yielded a sample of 1543 events, including an expected background of 56±856 \pm 8 events. An effective form factor was determined from the observed distribution of the e+ee^+e^- invariant mass. Using this form factor in the calculation of the detector acceptance, the branching ratio was measured to be B(KLe+eγγ,Eγ>5MeV)=(5.84±0.15 (stat)±0.32 (sys))×107{\mathcal B}(K_L \to e^+ e^- \gamma \gamma, E^*_\gamma > 5 {MeV}) = (5.84 \pm 0.15 {\rm ~(stat)} \pm 0.32 {\rm ~(sys)})\times 10^{-7}.Comment: 5 pages, 4 figure
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