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Conventional Tests (conventional + test)
Selected AbstractsApplication of graph theory to detect disconnected structures in a crystallographic database: copper oxide perovskites as a case studyACTA CRYSTALLOGRAPHICA SECTION B, Issue 6 2000Yuri Kotliarov Every crystal structure can be described as a graph with atoms as vertices and bonds as edges. Although such a graph loses the space arrangement of atoms and symmetry elements, it can mathematically represent the connectivity between atoms. This topological approach was used to develop a new method for detecting disconnected structures, in which individual atoms or structural fragments are located too far from each other, forming impossibly large gaps. Approximately 2300 perovskite-related crystal structures have been extracted from the Inorganic Crystal Structure Database (in 1999) and the maximum disconnecting distances, and the relations between them and the ionic radii of elements, have been analysed. Several disconnected structures, which are erroneous by our definition, have been revealed. Conventional tests for crystallographic data checking did not detect those entries. [source] Assessment of liver function for safe hepatic resectionHEPATOLOGY RESEARCH, Issue 2 2009Yasuji Seyama The preoperative assessment of liver function is extremely important for preventing postoperative liver failure and mortality after hepatic resection. Liver function tests may be divided into three types; conventional liver function tests, general scores, and quantitative liver function tests. General scores are based on selected clinical symptoms and conventional test results. Child,Turcotte,Pugh score has been the gold standard for four decades, but the Child,Turcotte,Pugh score has difficulty discriminating a good risk from a poor risk in patients with mild to moderate liver dysfunction. The model for end-stage liver disease score has also been applied to predict short-term outcome after hepatectomy, but it is only useful in patients with advanced cirrhosis. Quantitative liver function tests overcome the drawbacks of general scores. The indocyanine green retention rate at 15 minutes (ICG R15) has been reported to be a significant predictor of postoperative liver failure and mortality. The safety limit of the hepatic parenchymal resection rate can be estimated using the ICG R15, and a decision tree (known as the Makuuchi criteria) for selecting patients and hepatectomy procedures has been proposed. Hepatic resection can be performed with a mortality rate of nearly zero using this decision tree. If the future remnant liver volume does not fulfill the Makuuchi criteria, preoperative portal vein embolization should be performed to prevent postoperative liver failure. Galactosyl human serum albumin-diethylenetriamine-pentaacetic acid scintigraphy also provides data that complement the ICG test. Other quantitative liver function tests, however, require further validation and simplification. [source] Validation of the Severe Impairment Battery for patients with Alzheimer's disease in KoreaINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 7 2006Guk-Hee Suh Abstract Objective To examine the reliability and the validity of the Korean version of the SIB (SIB-K); and to determine its usefulness in patients with severe dementia. Methods Sixty-five patients (56 women, nine men) who lived in a nursing home and met the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edn, for the dementia of the Alzheimer's type were selected. Following clinical examination and evaluation using the Korean version of the Severe Impairment Battery (SIB-K), the Korean versions of the Mini-Mental State Examination (MMSE-K) and the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-K-cog) were applied as comparators. Results The mean scores on the SIB-K were 63.9 (SD,=,29.1), with a possible maximum of 100 points. Patients with MMSE scores from 0 to 4 points showed wide range of the SIB score from 4 to 62. The internal consistency of the SIB-K obtained by the Cronbach's alpha was 0.98. The inter-rater and test,retest reliabilities of the SIB-K obtained by the Spearman's rho were 0.99 and 0.97, respectively. Correlation between the SIB-K and the MMSE-K was 0.87, while correlation between the SIB-K and the ADAS-K-cog was ,0.76. Conclusions This study indicates that the Korean version of the SIB is a reliable, valid and useful test for measuring cognition of severely demented patients at a point where other conventional tests lose their sensitivity and show a floor effect. Copyright © 2006 John Wiley & Sons, Ltd. [source] Strategic bias and professional affiliations of macroeconomic forecastersJOURNAL OF FORECASTING, Issue 2 2009Masahiro AshiyaArticle first published online: 19 SEP 200 Abstract This paper investigates strategic motives of macroeconomic forecasters and the effect of their professional affiliations. The ,wishful expectations hypothesis' suggests that a forecaster predicts what his employer wishes. The ,publicity hypothesis' argues that forecasters are evaluated by both accuracy and ability to generate publicity, and that forecasters in industries that emphasize publicity most will make most extreme and least accurate predictions. The ,signaling hypothesis' asserts that an extreme forecast signals confidence in own ability, because incompetent forecasters would mimic others to avoid public notice. Empirical evidence from a 26-year panel of annual GDP forecasts is con-sistent with the publicity hypothesis. This indicates that conventional tests of rationality are biased toward rejecting the rational expectations hypothesis. Copyright ? 2008 John Wiley & Sons, Ltd. [source] Longitudinal estimation of signal-averaged electrocardiograms in patients with Kawasaki diseasePEDIATRICS INTERNATIONAL, Issue 1 2002Yukio Kuramochi Abstract Background:,Myocarditis associated with Kawasaki (KD) disease is prominent, but rarely detected by conventional methods. The hypothesis of this study is to see if signal-averaged electrocardiogram can detect myocarditis with KD. Methods:,We obtained signal-averaged electrocardiograms from 71 patients with KD (mean age 2.8 ± 2.9 years) in the acute (1st,4th week), subacute (5,7th week), and chronic (8th week or later) phases (mean study period 3.5 ± 1.7 years). Sixteen patients who had pericardial effusion, bundle branch block or myocardial ischemia were excluded from this study. The results were compared with those of Holter and 12-lead electrocardiograms, echocardiography and serum myocardial enzymes. They were also contrasted with the course of each patient. Results:,The incidence of abnormal findings on signal-averaged electrocardiogram was 18.2% in the acute phase versus 10.9% in the subacute and chronic phases. It differed significantly higher than the other conventional tests (P < 0.05). Four patients had abnormalities of signal-averaged electrocardiograms through all three phases. Among these four, two had reduced left ventricular contractility. However, these changes were transient and resolved in the subacute phase. All patients had good courses and no residue. Conclusion:,This study shows the possibility that signal-averaged electrocardiogram is more useful to detect myocarditis associated with KD than the other conventional tests. However, we could not define the prognostic value of abnormal signal-averaged electrocardiograms during this study period. [source] Hair Analysis Versus Conventional Methods of Drug Testing in Substance Abusers Seeking Organ TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010D. L. Haller As substance abusers need to demonstrate abstinence prior to transplant, valid/reliable drug tests are needed. Patients may deny use, fearing surgery will be delayed. Breath, blood and urine tests have brief detection windows that allow patients to evade detection. Routine laboratory tests do not include all substances of abuse. Hair analysis overcomes these barriers, increasing the likelihood that active users will be identified. This study compared results for alcohol, opioids and cocaine based on 445 self-report, breath, urine and hair samples from 42 patients who had been denied a transplant due to recent substance abuse. Compared to hair toxicology, sensitivity for conventional drug tests was moderate for cocaine and opioids, but poor for alcohol. Of positive hair tests, only half were corroborated through other tests. In contrast, specificity was high across tests and substances, with positive findings from conventional tests confirmed through hair toxicology. Based on a 90-day detection window for hair analysis, two negative tests suggest 6 months of continuous abstinence. Hair testing should be considered as an alternative approach for monitoring substance use in the transplant population, either as a routine procedure or when the veracity of findings from conventional tests is in doubt. [source] Exact, Distribution Free Confidence Intervals for Late Effects in Censored Matched PairsBIOMETRICAL JOURNAL, Issue 1 2009Shoshana R. Daniel Abstract When comparing censored survival times for matched treated and control subjects, a late effect on survival is one that does not begin to appear until some time has passed. In a study of provider specialty in the treatment of ovarian cancer, a late divergence in the Kaplan,Meier survival curves hinted at superior survival among patients of gynecological oncologists, who employ chemotherapy less intensively, when compared to patients of medical oncologists, who employ chemotherapy more intensively; we ask whether this late divergence should be taken seriously. Specifically, we develop exact, permutation tests, and exact confidence intervals formed by inverting the tests, for late effects in matched pairs subject to random but heterogeneous censoring. Unlike other exact confidence intervals with censored data, the proposed intervals do not require knowledge of censoring times for patients who die. Exact distributions are consequences of two results about signs, signed ranks, and their conditional independence properties. One test, the late effects sign test, has the binomial distribution; the other, the late effects signed rank test, uses nonstandard ranks but nonetheless has the same exact distribution as Wilcoxon's signed rank test. A simulation shows that the late effects signed rank test has substantially more power to detect late effects than do conventional tests. The confidence statement provides information about both the timing and magnitude of late effects (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||