Publications by authors named "W G Lotz"

The MEdium Resolution Imaging Spectrometer (MERIS) instrument on board ESA Envisat made measurements from 2002 to 2012. Although MERIS was limited in spectral coverage, accurate Aerosol Optical Thickness (AOT) from MERIS data are retrieved by using appropriate additional information. We introduce a new AOT retrieval algorithm for MERIS over land surfaces, referred to as eXtensible Bremen AErosol Retrieval (XBAER).

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The increasingly popular practice of using a stability ball (exercise/fitness ball) as a sitting surface runs counter to conventional human factors/ergonomics guidelines for seated workspace design. Employees sitting on stability balls in an office environment present safety risks that might be justifiable if the practice has a definitive benefit to the promotion of health. However, the published studies and best evidence to date call into question even the theoretical basis for this practice and do not suggest significant health benefits.

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A Bayesian network model was developed to integrate diverse types of data to conduct an exposure-dose-response assessment for benzene-induced acute myeloid leukemia (AML). The network approach was used to evaluate and compare individual biomarkers and quantitatively link the biomarkers along the exposure-disease continuum. The network was used to perform the biomarker-based dose-response analysis, and various other approaches to the dose-response analysis were conducted for comparison.

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The widespread use of wireless telecommunications devices, particularly mobile phones and wireless networks, has resulted in increased human exposure to radiofrequency (RF) fields. Although national and international agencies have established safety guidelines for exposure to RF fields, concerns remain about the potential for adverse health outcomes to occur in relation to RF field exposure. The extensive literature on RF fields and health was reviewed by a number of authorities, including the Royal Society of Canada (1999).

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Immunocompromised patients with acid-fast bacilli (AFB) smear-negative active pulmonary tuberculosis (pTB) often present with nonspecific clinical symptoms and findings. T-cell interferon-gamma release assays (TIGRA) performed on whole blood (using ELISA) or peripheral blood mononuclear cells (using enzyme-linked immunospot assay (ELISPOT)) are more sensitive for the diagnosis of Mycobacterium tuberculosis (MTB) infection than the tuberculin skin test (TST), but cannot distinguish active from latent MTB infection. The present authors report a 38-yr-old female presenting with a 3-week history of malaise, dyspnoea, fevers and coughing, who had received immunosuppressive therapies over 8 months for mixed connective tissue disease.

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