88 resultados para scientific controversy


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Vertical profiles of stratospheric water vapour measured by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) with the full resolution mode between September 2002 and March 2004 and retrieved with the IMK/IAA scientific retrieval processor were compared to a number of independent measurements in order to estimate the bias and to validate the existing precision estimates of the MIPAS data. The estimated precision for MIPAS is 5 to 10% in the stratosphere, depending on altitude, latitude, and season. The independent instruments were: the Halogen Occultation Experiment (HALOE), the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS), the Improved Limb Atmospheric Spectrometer-II (ILAS-II), the Polar Ozone and Aerosol Measurement (POAM III) instrument, the Middle Atmospheric Water Vapour Radiometer (MIAWARA), the Michelson Interferometer for Passive Atmospheric Sounding, balloon-borne version (MIPAS-B), the Airborne Microwave Stratospheric Observing System (AMSOS), the Fluorescent Stratospheric Hygrometer for Balloon (FLASH-B), the NOAA frostpoint hygrometer, and the Fast In Situ Hygrometer (FISH). For the in-situ measurements and the ground based, air- and balloon borne remote sensing instruments, the measurements are restricted to central and northern Europe. The comparisons to satellite-borne instruments are predominantly at mid- to high latitudes on both hemispheres. In the stratosphere there is no clear indication of a bias in MIPAS data, because the independent measurements in some cases are drier and in some cases are moister than the MIPAS measurements. Compared to the infrared measurements of MIPAS, measurements in the ultraviolet and visible have a tendency to be high, whereas microwave measurements have a tendency to be low. The results of χ2-based precision validation are somewhat controversial among the comparison estimates. However, for comparison instruments whose error budget also includes errors due to uncertainties in spectrally interfering species and where good coincidences were found, the χ2 values found are in the expected range or even below. This suggests that there is no evidence of systematically underestimated MIPAS random errors.

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The indications for screening and TSH threshold levels for treatment of subclinical hypothyroidism have remained a clinical controversy for over 20 years. Subclinical thyroid dysfunction is a common finding in the growing population of older adults, occurring in 10–15% among those age 65 and older, and may contribute to multiple common problems of older age, including cardiovascular disease, muscular impairment, mood problems, and cognitive dysfunction (1). In 2004, both the U.S. Preventive Services Task Force (2) and a clinical consensus group of experts (3) concluded that the existing evidence about the association between subclinical hypothyroidism and cardiovascular risks, primarily cross-sectional or case-control studies (4), was insufficient. For example, a frequently cited analysis from the Rotterdam study found a cross-sectional association between subclinical hypothyroidism and atherosclerosis, as measured by abdominal aortic calcification (odds ratio, 1.7; 95% confidence interval [CI], 1.1–2.6) and prevalent myocardial infarction (MI) (odds ratio, 2.3; 95% CI, 1.3–4.0) (5). Conversely, the prospective part of this study included only 16 incident MIs; the hazard ratio (HR) for subclinical hypothyroidism was 2.50, with broad 95% CIs (0.70–9.10). Potential mechanisms for the associations with cardiovascular diseases among adults with subclinical hypothyroidism include elevated cholesterol levels, inflammatory markers, raised homocysteine, increased oxidative stress, insulin resistance, increased systemic vascular resistance, arterial stiffness, altered endothelial function, and activation of thrombosis and hypercoagulability that have all been reported to be associated with subclinical hypothyroidism (1, 6).

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Squamous cell carcinoma (SCC) of the maxillary sinus is a relatively rare disease. As the reported incidence of regional metastasis varies widely, controversy exists as to whether or not the N0 classified neck should be treated electively. In this review, the data from published series are analyzed to decide on a recommendation of elective treatment of the neck in maxillary SCC. The published series consist of heterogeneous populations of different subsites of the paranasal sinuses, different histological types, different staging and treatment modalities used and different ways of reporting the results. These factors do not allow for recommendations based on high levels of evidence. Given this fact, the relatively high incidence rate of regional metastasis at presentation or in follow-up in the untreated N0 neck, and the relatively low toxicity of elective neck irradiation, such irradiation in SCC of the maxillary sinus should be considered.

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This contribution deals with psychological vulnerability resulting from marital breakup after a long-term relationship. Despite the existing vast body of consolidated knowledge on divorce and psychological adaptation, there are still several controversies concerning the vulnerabilizing impact of marital breakup. One major issue refers to the question of whether vulnerability after marital breakup is a temporary crisis or rather a chronic strain. In this chapter we want to present two possible methodological options to tackle this question: First, comparing a sample of almost 1000 middle-aged persons, who were married on average 19 years, and who experienced a marital split within the last 5 years (4 time groups), with a group of age-matched married controls with regard to various indicators of psychological vulnerability (such as depression and hopelessness). Second, comparing within the divorced group the most vulnerable individuals (in terms of depression, hopelessness, life satisfaction) with those who were the least affected, regarding intra-personal resources (personality, resilience), divorce circumstances, post-divorce situation, and socio-economic resources. The study results underline the vulnerabilizing impact of marital breakup, but at the same time they reveal individual differences in psychological adaptation especially due to personality, new partnership, economic resources, and last but not least due to time. Furthermore our data strongly suggest that there is not a generalized psychological vulnerability after marital breakup, but that the emotional dimensions such as depression or feelings of not overcoming the loss are more affected than the more cognitive ones such as life satisfaction.

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Is numerical mimicry a third way of establishing truth? Kevin Heng received his M.S. and Ph.D. in astrophysics from the Joint Institute for Laboratory Astrophysics (JILA) and the University of Colorado at Boulder. He joined the Institute for Advanced Study in Princeton from 2007 to 2010, first as a Member and later as the Frank & Peggy Taplin Member. From 2010 to 2012 he was a Zwicky Prize Fellow at ETH Z¨urich (the Swiss Federal Institute of Technology). In 2013, he joined the Center for Space and Habitability (CSH) at the University of Bern, Switzerland, as a tenure-track assistant professor, where he leads the Exoplanets and Exoclimes Group. He has worked on, and maintains, a broad range of interests in astrophysics: shocks, extrasolar asteroid belts, planet formation, fluid dynamics, brown dwarfs and exoplanets. He coordinates the Exoclimes Simulation Platform (ESP), an open-source set of theoretical tools designed for studying the basic physics and chemistry of exoplanetary atmospheres and climates (www.exoclime.org). He is involved in the CHEOPS (Characterizing Exoplanet Satellite) space telescope, a mission approved by the European Space Agency (ESA) and led by Switzerland. He spends a fair amount of time humbly learning the lessons gleaned from studying the Earth and Solar System planets, as related to him by atmospheric, climate and planetary scientists. He received a Sigma Xi Grant-in-Aid of Research in 2006