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Residual Uncertainties (residual + uncertainty)
Selected AbstractsQuantitative and qualitative methods in UK health research: then, now and . . . ?EUROPEAN JOURNAL OF CANCER CARE, Issue 3 2002K. Mcpherson phd Quantitative and qualitative methods in UK health research: then, now and . . . ? This paper examines the current status of qualitative and quantitative research in the context of UK (public) health research in cancer. It is proposed that barren competition between qualitative and quantitative methods is inevitable, but that effective synergy between them continues to be essential to research excellence. The perceived methodological utility, with respect to understanding residual uncertainties, can account for the status accorded various research techniques and these will help to explain shifts witnessed in recent years and contribute towards an understanding of what can be realistically expected in terms of future progress. It is argued that the methodological debate, though familiar to many, is worthy of rearticulation in the context of cancer research where the psychosocial aspects of living with a cancer and the related complexity of providing appropriate cancer care are being addressed across Europe, as evidenced in recent directions in policy and research. [source] Estimating the spectral indices of correlated astrophysical foregrounds by a second-order statistical approachMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2006A. Bonaldi ABSTRACT We present the first tests of a new method, the correlated component analysis (CCA) based on second-order statistics, to estimate the mixing matrix, a key ingredient to separate astrophysical foregrounds superimposed to the Cosmic Microwave Background (CMB). In the present application, the mixing matrix is parametrized in terms of the spectral indices of Galactic synchrotron and thermal dust emissions, while the free,free spectral index is prescribed by basic physics, and is thus assumed to be known. We consider simulated observations of the microwave sky with angular resolution and white stationary noise at the nominal levels for the Planck satellite, and realistic foreground emissions, with a position-dependent synchrotron spectral index. We work with two sets of Planck frequency channels: the low-frequency set, from 30 to 143 GHz, complemented with the Haslam 408 MHz map, and the high-frequency set, from 217 to 545 GHz. The concentration of intense free,free emission on the Galactic plane introduces a steep dependence of the spectral index of the global Galactic emission with Galactic latitude, close to the Galactic equator. This feature makes difficult for the CCA to recover the synchrotron spectral index in this region, given the limited angular resolution of Planck, especially at low frequencies. A cut of a narrow strip around the Galactic equator (|b| < 3°), however, allows us to overcome this problem. We show that, once this strip is removed, the CCA allows an effective foreground subtraction, with residual uncertainties inducing a minor contribution to errors on the recovered CMB power spectrum. [source] Evaluation of megavoltage CT imaging protocols in patients with lung cancerJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 1 2010S Smith Summary Currently, megavoltage CT studies in most centres with tomotherapy units are performed prior to every treatment for patient set-up verification and position correction. However, daily imaging adds to the total treatment time, which may cause patient discomfort as well as results in increased imaging dose. In this study, four alternative megavoltage CT imaging protocols (images obtained: during the first five fractions, once per week, alternating fractions and daily on alternative weeks) were evaluated retrospectively using the daily position correction data for 42 patients with lung cancer. The additional uncertainty introduced by using a specific protocol with respect to the daily imaging, or residual uncertainty, was analysed on a patient and population bases. The impact of less frequent imaging schedules on treatment margin calculation was also analysed. Systematic deviations were reduced with increased imaging frequency, while random deviations were largely unaffected. Mean population systematic errors were small for all protocols evaluated. In the protocol showing the greatest error, the treatment margins necessary to accommodate residual errors were 1.2, 1.3 and 1.7 mm larger in the left,right, superior,inferior and anterior,posterior directions, respectively, compared with the margins calculated using the daily imaging data. The increased uncertainty because of the use of less frequent imaging protocols may be acceptable when compared with other sources of uncertainty in lung cancer cases, such as target volume delineation and motion because of respiration. Further work needs to be carried out to establish the impact of increased residual errors on dose distribution. [source] On the Edge of the Law: Women's Property Rights and Dispute Resolution in Kisii, KenyaLAW & SOCIETY REVIEW, Issue 1 2009Elin Henrysson Scholars have argued that economic efficiency requires a clear definition of the rights of ownership, contract, and transfer of land. Ambiguity in the definition or enforcement of any of these rights leads to an increase in transaction costs in the exchange and transfer of land as well as a residual uncertainty after any land contract. In Kenya, government efforts at establishing clearly defined property rights and adjudication mechanisms have been plagued by the existence of alternative processes for the adjudication of disputes. Customary dispute resolution has been praised as an inexpensive alternative to official judicial processes in a legally pluralistic environment. However, our research demonstrates that customary processes may also carry a monetary cost that puts them beyond the means of many citizens. This article compares the costs and processes of the formal and informal methods of property rights adjudication for women in the Kisii region of Kenya. The research results suggest that women have weak property rights overall, they have limited access to formal dispute resolution systems because of costs involved, and even the informal systems of conflict resolution are beyond the means of many citizens. [source] | ||||||||||