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Selected AbstractsInteractive Graphics for Computer Adaptive TestingCOMPUTER GRAPHICS FORUM, Issue 8 2009I. Cheng K.3.1 [Computer Milieux]: Computer and Education , Computer Uses in Education; I.3.8 [Computing Methodologies]: Computer Graphics , Application Abstract Interactive graphics are commonly used in games and have been shown to be successful in attracting the general audience. Instead of computer games, animations, cartoons, and videos being used only for entertainment, there is now an interest in using interactive graphics for ,innovative testing'. Rather than traditional pen-and-paper tests, audio, video and graphics are being conceived as alternative means for more effective testing in the future. In this paper, we review some examples of graphics item types for testing. As well, we outline how games can be used to interactively test concepts; discuss designing chemistry item types with interactive 3D graphics; suggest approaches for automatically adjusting difficulty level in interactive graphics based questions; and propose strategies for giving partial marks for incorrect answers. We study how to test different cognitive skills, such as music, using multimedia interfaces; and also evaluate the effectiveness of our model. Methods for estimating difficulty level of a mathematical item type using Item Response Theory (IRT) and a molecule construction item type using Graph Edit Distance are discussed. Evaluation of the graphics item types through extensive testing on some students is described. We also outline the application of using interactive graphics over cell phones. All of the graphics item types used in this paper are developed by members of our research group. [source] Acute and chronic toxicity of mercury to early life stages of the rainbow mussel, Villosa iris (Bivalvia: Unionidae)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2005Theodore W. Valenti Abstract Mercury (Hg) contamination is receiving increased attention globally because of human health and environmental concerns. Few laboratory studies have examined the toxicity of Hg on early life stages of freshwater mussels, despite evidence that glochidia and juvenile life stages are more sensitive to contaminants than adults. Three bioassays (72-h acute glochidia, 96-h acute juvenile, and 21-d chronic juvenile toxicity tests) were conducted by exposing Villosa iris to mercuric chloride salt (HgCl2). Glochidia were more sensitive to acute exposure than were juvenile mussels, as 24-, 48-, and 72-h median lethal concentration values (LC50) for glochidia were >107, 39, and 14 ,g Hg/L, respectively. The 24-, 48-, 72-, and 96-h values for juveniles were 162, 135, 114, and 99 ,g Hg/L, respectively. In the chronic test, juveniles exposed to Hg treatments ,8 ,g/L grew significantly less than did control organisms. The substantial difference in juvenile test endpoints emphasizes the importance of assessing chronic exposure and sublethal effects. Overall, our study supports the use of glochidia as a surrogate life stage for juveniles in acute toxicity tests. However, as glochidia may be used only in short-term tests, it is imperative that an integrated approach be taken when assessing risk to freshwater mussels, as their unique life history is atypical of standard test organisms. Therefore, we strongly advocate the use of both glochidia and juvenile life stages for risk assessment. [source] Linkage disequilibrium estimates of contemporary Ne using highly variable genetic markers: a largely untapped resource for applied conservation and evolutionEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 3 2010Robin S. Waples Abstract Genetic methods are routinely used to estimate contemporary effective population size (Ne) in natural populations, but the vast majority of applications have used only the temporal (two-sample) method. We use simulated data to evaluate how highly polymorphic molecular markers affect precision and bias in the single-sample method based on linkage disequilibrium (LD). Results of this study are as follows: (1) Low-frequency alleles upwardly bias , but a simple rule can reduce bias to Heterodimerization with LBP-1b is necessary for nuclear localization of LBP-1a and LBP-1cGENES TO CELLS, Issue 9 2005Fuyuhiko Sato The LBP-1 family consists of four proteins, which act as transcription factors in the formation of dimers with a member of this family. LBP-1a and LBP-1b are splicing variants from one gene, and LBP-1c and LBP-1d also arise from the alternative splicing of another gene. Investigation of subcellular localization of LBP-1 proteins fused to YFP revealed that the LBP-1b was localized in the nucleus, whereas LBP-1a and LBP-1c were exclusively localized in the cytosol. The peptide of 36 amino acids encoded by exon 6, a specific exon used only for LBP-1b, possessed the function of a nuclear localization signal (NLS). Nuclear localization of LBP-1a and LBP-1c occurred when LBP-1b was co-expressed, suggesting that heterodimerization of LBP-1a and LBP-1c with LBP-1b is important for their nuclear transport. Transiently expressed LBP-1 proteins in COS-7 cells formed speckles in the nucleus. Most speckles overlapped with the PML body. The activity of LBP-1a for accumulation in the PML body was mapped in the N-terminal region. [source] Measuring health polarization with self-assessed health dataHEALTH ECONOMICS, Issue 9 2007Benedicte ApoueyArticle first published online: 20 AUG 200 Abstract This paper proposes an axiomatic foundation for new measures of polarization that can be applied to ordinal distributions such as self-assessed health (SAH) data. This is an improvement over the existing measures of polarization that can be used only for cardinal variables. The new measures of polarization avoid one difficulty that the related measures for evaluating health inequalities face. Indeed, inequality measures are mean based, and since only cardinal variables have a mean, SAH has to be cardinalized to compute a mean, which can then be used to calculate an inequality measure. In contrast, the new polarization measures are median based and hence do not require to impose cardinal scaling on the categories. After deriving the properties of these new polarization measures, we provide an empirical illustration using data from the British Household Panel Survey that demonstrates that SAH polarization is also a relevant question on empirical grounds, and that the polarization measures are adequate to evaluate polarization phenomena whereas inequality measures are not adequate in these cases. Copyright © 2007 John Wiley & Sons, Ltd. [source] Quantification of immunohistochemistry,issues concerning methods, utility and semiquantitative assessment IHISTOPATHOLOGY, Issue 4 2006R A Walker Immunohistochemistry is no longer a technique used only for research but is employed increasingly for diagnosis and for the assessment of therapeutic biomarkers. The latter, in particular, often require a semiquantitative evaluation of the extent of their presence. There are many factors that can affect this that relate to the method: fixation of tissue, duration and type of antigen retrieval, antibody specificity, antibody dilution and detection systems. Other complexities relate to assessment. Different scoring systems are used for either the same or different antigens. Cut-off levels for assessing whether a tissue is ,positive' or ,negative' can vary for the same antigen. Whilst there are quality assurance schemes for the methodology that have improved standards of staining, there are no similar schemes that relate to interpretation, although errors here can create as many problems. There have been improvements in automated analysis but availability is limited and it is still predominantly a research tool. In order for quantification of immunohistochemistry to be a reliable and reputable tool, there must be easy to use, reproducible, standardized protocols for assessment which are international. Improvements in automated analysis with wider applicability could lead to standardization. [source] The role of the mother's voice in developing mother's face preference: Evidence for intermodal perception at birthINFANT AND CHILD DEVELOPMENT, Issue 1 2005F. Z. Sai Abstract Four experiments are described which investigated the role of the mother's voice in facilitating recognition of the mother's face at birth. Experiment 1 replicated our previous findings (Br. J. Dev. Psychol. 1989; 7: 3,15; The origins of human face perception by very young infants. Ph.D. Thesis, University of Glasgow, Scotland, UK, 1990) indicating a preference for the mother's face when a control for the mother's voice and odours was used only during the testing. A second experiment adopted the same procedures, but controlled for the mother's voice from birth through testing. The neonates were at no time exposed to their mother's voice. Under these conditions, no preference was found. Further, neonates showed only few head turns towards both the mother and the stranger during the testing. Experiment 3 looked at the number of head turns under conditions where the newborn infants were exposed to both the mother's voice and face from birth to 5 to 15 min prior to testing. Again, a strong preference for the mother's face was demonstrated. Such preference, however, vanished in Experiment 4, when neonates had no previous exposure to the mother's voice,face combination. The conclusion drawn is that a prior experience with both the mother's voice and face is necessary for the development of face recognition, and that intermodal perception is evident at birth. The neonates' ability to recognize the face of the mother is most likely to be rooted in prenatal learning of the mother's voice. Copyright © 2004 John Wiley & Sons, Ltd. [source] Consistent coupling of beam and shell models for thermo-elastic analysisINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 14 2004K. S. Chavan Abstract In this paper, the finite element formulation of a transition element for consistent coupling between shell and beam finite element models of thin-walled beam-like structures in thermo-elastic problems is presented. Thin-walled beam-like structures modelled only with beam elements cannot be used to study local stress concentrations or to provide local mechanical or thermal boundary conditions. For this purpose, the structure has to be modelled using shell elements. However, computations using shell elements are a lot more expensive as compared to beam elements. The finite element model can be more efficient when the shell elements are used only in regions where the local effects are to be studied or local boundary conditions have to be provided. The remaining part of the structure can be modelled with beam elements. To couple these two models (i.e. shell and beam models) at transitional cross-sections, transition elements are derived here for thermo-elastic problems. The formulation encloses large displacement and rotational behaviour, which is important in case of thin-walled beam-like structures. Copyright © 2004 John Wiley & Sons, Ltd. [source] Numerical errors of the volume-of-fluid interface tracking algorithmINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 4 2002Gregor, erne Abstract One of the important limitations of the interface tracking algorithms is that they can be used only as long as the local computational grid density allows surface tracking. In a dispersed flow, where the dimensions of the particular fluid parts are comparable or smaller than the grid spacing, several numerical and reconstruction errors become considerable. In this paper the analysis of the interface tracking errors is performed for the volume-of-fluid method with the least squares volume of fluid interface reconstruction algorithm. A few simple two-fluid benchmarks are proposed for the investigation of the interface tracking grid dependence. The expression based on the gradient of the volume fraction variable is introduced for the estimation of the reconstruction correctness and can be used for the activation of an adaptive mesh refinement algorithm. Copyright © 2002 John Wiley & Sons, Ltd. [source] New immunochemical fecal occult blood test with two-consecutive stool sample testing is a cost-effective approach for colon cancer screening: Results of a prospective multicenter study in Chinese patientsINTERNATIONAL JOURNAL OF CANCER, Issue 12 2006Shirong Li Abstract The purpose of the study is to evaluate a new immunochemical fecal occult blood test method (Hemosure IFOBT), and compare it to the Guaiac-based chemical method (CFOBT) for colorectal cancer detection. A hypothetical sequential method (SFOBT), in which IFOBT was used only as a confirmatory test for CFOBT, was also evaluated. A total of 324 patients were recruited from 5 major hospitals in Beijing, China. For each patient, 3 consecutive stool samples were collected for simultaneous CFOBT and IFOBT tests, followed by colonoscopic examination. We compared the sensitivity and specificity of the 3 methods (CFOBT, IFOBT and SFOBT) in two settings, with the first 2 consecutive samples versus all 3 samples. Although the sensitivity for the detection of cancer and large (>20 mm) or multiple adenoma was similar for all 3 methods in the three-sample setting, in the two-sample setting IFOBT had higher sensitivity than SFOBT for detecting cancer (87.8% vs. 75.5%, respectively, p < 0.05) and large (>20 mm) or multiple adenomas (65.4% vs. 42.3%, respectively, p < 0.05). The IFOBT also had a higher specificity than the CFOBT (89.2% vs. 75.5%, respectively, p < 0.01) in "normal" individuals defined by colonoscopy in the three-sample setting. Comparing two-sample setting to the three-sample setting, both CFOBT and SFOBT showed significant loss of sensitivity for the detection of cancer as well as adenoma, whereas the sensitivity for IFOBT did not change significantly. Overall, IFOBT with two-sample testing showed compatible sensitivity and specificity to the three-sample testing, and had a lower relative cost per cancer detected than the three-sample testing. In conclusion, the new Hemosure IFOBT with two consecutive stool samples appears to be the most cost-effective approach for colon cancer screening. © 2006 Wiley-Liss, Inc. [source] Formation and decay of the ABTS derived radical cation: A comparison of different preparation proceduresINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 12 2002Carola Henriquez Bleaching of a preformed solution of the blue-green radical cation 2,2,-azinobis (3-ethylbenzothizoline-6-sulfonic acid) (ABTS+·) has been extensively used to evaluate the antioxidant capacity of complex mixtures and individual compounds. The reaction of the preformed radical with free-radical scavengers can be easily monitored by following the decay of the sample absorbance at 734 nm. The ABTS radical cation can be prepared employing different oxidants. Results obtained using MnO2 as oxidant show that the presence of manganese ions increases the rate of [ABTS]+· autobleaching in a concentration-dependent manner. The radicals can also be obtained by oxidizing ABTS with 2,2, -azobis(2-amidinopropane)hydrochloride (AAPH) or peroxodisulfate (PDS). The oxidation by AAPH takes place with a large activation energy and a low reaction order in ABTS. The data support a mechanism in which the homolysis of AAPH is the rate-limiting step, followed by the reaction of ABTS with the peroxyl radicals produced after the azocompound thermolysis. On the other hand, the low activation energy measured employing PDS, as well as the kinetic law, are compatible with the occurrence of a bimolecular reaction between the oxidant and ABTS. Regarding the use of ABTS-based methodologies for the evaluation of free radical scavengers, radical cations obtained employing AAPH as oxidant can be used only at low temperatures, conditions where further decomposition of the remaining AAPH is minimized. The best results are obtained with ABTS derived radicals generated in the reaction of PDS with an ABTS/PDS concentration ratio equal (or higher) to two. However, even with radicals prepared by this procedure, stoichiometric coefficients considerably larger than two are obtained for the consumption of the radical cation employing tryptophane or p -terbutylphenol as reductants. This casts doubts on the use of ABTS-based procedures for the estimation of antioxidant capacities. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 659,665, 2002 [source] Head-to-head comparison of risedronate vs. teriparatide on bone turnover markers in women with postmenopausal osteoporosis: a randomised trialINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 6 2008A. D. Anastasilakis Summary Aims:, We aimed to compare the effect of risedronate (RIS) and teriparatide (TPTD) (recombinant human parathyroid hormone 1,34) on bone turnover markers in women with postmenopausal osteoporosis. Methods:, Forty-four Caucasian women (age 65.1 ± 1.6 years) with postmenopausal osteoporosis were randomly assigned to receive either RIS 35 mg once weekly (n = 22) or TPTD 20 ,g once daily (n = 22) for 12 months. Serum N-terminal propeptide of type 1 collagen (P1NP), C-terminal telopeptide of type 1 collagen (CTx), total alkaline phosphatase (ALP) and intact parathyroid hormone (iPTH) were obtained from all women before, 3 and 6 months after treatment initiation. Lumbar spine bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry before and 12 months after treatment initiation. Results:, P1NP, CTx and total ALP levels decreased in RIS group (p < 0.001) and increased in TPTD group (p < 0.001) throughout the treatment. iPTH increased significantly in RIS group (p < 0.05) and decreased in TPTD group (p < 0.001). Finally, lumbar spine BMD increased significantly in both RIS (p = 0.003) and TPTD groups (p < 0.001) without significant differences between them. Conclusions:, Our data suggest that both serum P1NP and CTx are reliable markers of RIS and TPTD action in women with postmenopausal osteoporosis. In a similar way, serum total ALP can be used as an alternative marker for monitoring both RIS and TPTD action, while iPTH can be used only for TPTD-treated women. The increase in P1NP and CTx after 3 months of treatment with RIS or TPTD can predict the increase in BMD after 12 months of treatment. [source] Inter-particle contact heat transfer model: an extension to soils at elevated temperaturesINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 2 2005W. H. Leong Abstract A simple ,inter-particle contact heat transfer' model for predicting effective thermal conductivity of soils at moderate temperatures (0,30°C) has been extended up to 90°C. The extended model accounts for latent heat transport by water vapour diffusion in soil air above the permanent wilting point; below that point, the soil thermal conductivity is approximated by linear interpolation without latent heat effect. By and large the best results are obtained when the latent heat is used only in the ,self consistent approximation' model with an overall root mean square error of 35% for all soils under consideration or 26% when excluding volcanic soils. This option can also be applied to moderate temperatures at which the enhanced heat transfer is negligibly small. Copyright © 2005 John Wiley & Sons, Ltd. [source] Non-prescription medicine use by outpatients of a hospital in north-central Trinidad living with hypertension, and the potential clinical risksINTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 5 2008Miss Rian Extavour Assistant Lecturer, principal investigator Objective To describe the reported use of non-prescription medicines (NPMs) and the reported frequency of use by outpatients living with hypertension; to identify potential drug-drug and drug-disease interactions between reported NPMs and either antihypertensives prescribed or hypertension. Setting Adult outpatient clinics of the Eric Williams Medical Sciences Complex Adult Hospital in Trinidad. Method Outpatients were interviewed about their use of NPMs using a structured instrument. Chi-squared test or Fisher's exact test was used to test for associations between NPM use and selected variables: age group, gender, education level, number of prescribed medicines, use of prescribed medicines and the presence of comorbidities. Combinations of NPMs and antihypertensive drugs or hypertension itself that may lead to undesirable interactions were identified. Key findings One hundred and fifty-five clients were interviewed (mean age 61 years; 46% men; 56% of East Indian descent). Of these, 82% were living with a cardiac condition and 60% with diabetes mellitus. In addition, 92% reported using NPMs to treat minor illnesses. Analgesic use was reported by 81%. Some 66% reported using paracetamol, 54% reported antitussives, 48% antacids, 47% antihistamines and 39% said they used sympathomimetic drugs. The majority (98%) of NPMs were used only when needed. Sixty per cent had at least one combination a with risk of interaction with NPMs and hypertension or antihypertensive medicines: 16% had risk of interactions between enalapril (or captopril) and antacids, 13% between angiotensin-converting enzyme (ACE) inhibitors and non-steroidal anti-inflammatory drugs (NSAIDs), 12% between beta-blockers and NSAIDs and 12% between thiazide diuretics and NSAIDs. Thirty-nine per cent had a drug-disease interaction risk due to sympathomimetic drugs and 26% had one due to NSAID use. Conclusion Based on self-reports, outpatients living with hypertension in north-central Trinidad use NPMs when needed to treat minor illnesses, mainly paracetamol for pain. Non-prescription-antihypertensive interactions may arise due to ACE inhibitor/antacid combinations and NPM-hypertension interactions may result from use of sympathomimetics. Interactions may also arise as a result of the use of NPMs containing NSAIDs and sodium. [source] Spatial organization, group living and ecological correlates in low-density populations of Eurasian badgers, Meles melesJOURNAL OF ANIMAL ECOLOGY, Issue 3 2002Eloy Revilla Summary 1,Territoriality and group living are described in a low-density population of Eurasian badgers, Meles meles L., by studying the patterns of spatial grouping and territory marking, as well as the differences between individuals in some of their characteristics (body condition and dispersal) and in their space use (seasonally, periods of activity and interaction between pairs of individuals) under strong seasonal fluctuations in the availability of the key resource (young rabbits, Oryctolagus cuniculus L.). Finally, the role of the spatial distribution of the main prey (young rabbits) in the development of sociality was also studied in order to test some of the assumptions and predictions of the resource dispersion hypothesis (RDH). 2,Badgers were territorial, showing a flexible system of territory marking, which includes the marking of the most used areas (sett-latrines at the centres of activity) and additionally, at the smaller territories, a system of border-latrines in the areas of contact between territories. The maximum use of border-latrines was associated with the reproductive season, and that of sett-latrines with the season of food scarcity. 3,In the study area where badgers had rabbits as main prey, territories were occupied by small groups of animals, formed by one adult female who reproduced, one adult male who also showed signs of reproductive activity, the cubs of the year (if there was reproduction) and some animals born during previous years, which remained in their natal territory until their dispersal (normally during the mating season of their third or fourth year of life). This system was not strictly fixed as males, given the opportunity, expanded their territories to encompass additional females. Territories in another study site were occupied by one adult female (marked), plus the cubs of the year and another adult individual (unmarked). 4,In winter and spring dominant females and subordinates used only a small fraction of their territories, moved short distances, at a low speed and covering small areas per night. These seasons corresponded with the reproduction of rabbits (highest food availability). Dominant females were the only individuals using all the territory available in the summer (lowest food availability), when badgers had the worst body condition. Food availability increased again in autumn, as did body condition, while range sizes were again reduced. Dominant males used the same proportion of their territories over all seasons. However, in winter (reproductive season) they moved faster, over longer distances, and covered larger areas per period of activity. These results indicate that use of space by dominant males was affected by different factors from that of dominant females and subordinates. 5,RDH does not seem to explain group living in our populations because: (a) territoriality in each pair of primary animals was driven by different factors (trophic resources for females and females for males); (b) dominant males acted as expansionists; and (c) territory size was related to its richness and not to patch dispersion. 6,We propose an integrative hypothesis to explain not only group formation but also interpopulation variability in the social organization of badgers within ecological, demographic and behavioural constraints and in the light of current theory on delayed dispersal. [source] Changes in Bone Density During Childhood and Adolescence: An Approach Based on Bone's Biological OrganizationJOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2001Frank Rauch Abstract Bone densitometry has great potential to improve our understanding of bone development. However, densitometric data in children rarely are interpreted in light of the biological processes they reflect. To strengthen the link between bone densitometry and the physiology of bone development, we review the literature on physiological mechanisms and structural changes determining bone mineral density (BMD). BMD (defined as mass of mineral per unit volume) is analyzed in three levels: in bone material (BMDmaterial), in a bone's trabecular and cortical tissue compartments (BMDcompartment), and in the entire bone (BMDtotal). BMDmaterial of the femoral midshaft cortex decreases after birth to a nadir in the first year of life and thereafter increases. In iliac trabecular bone, BMDmaterial also increases from infancy to adulthood, reflecting the decrease in bone turnover. BMDmaterial cannot be determined with current noninvasive techniques because of insufficient spatial resolution. BMDcompartment of the femoral midshaft cortex decreases in the first months after birth followed by a rapid increase during the next 2 years and slower changes thereafter, reflecting changes in both relative bone volume and BMDmaterial. Trabecular BMDcompartment increases in vertebral bodies but not at the distal radius. Quantitative computed tomography (QCT) allows for the determination of both trabecular and cortical BMDcompartment, whereas projectional techniques such as dual-energy X-ray absorptiometry (DXA) can be used only to assess cortical BMDcompartment of long bone diaphyses. BMDtotal of long bones decreases by about 30% in the first months after birth, reflecting a redistribution of bone tissue from the endocortical to the periosteal surface. In children of school age and in adolescents, changes in BMDtotal are site-specific. There is a marked rise in BMDtotal at locations where relative cortical area increases (metacarpal bones, phalanges, and forearm), but little change at the femoral neck and midshaft. BMDtotal can be measured by QCT at any site of the skeleton, regardless of bone shape. DXA allows the estimation of BMDtotal at skeletal sites, which have an approximately circular cross-section. The system presented here may help to interpret densitometric results in growing subjects on a physiological basis. [source] Principles of Proper Validation: use and abuse of re-sampling for validationJOURNAL OF CHEMOMETRICS, Issue 3-4 2010Kim H. Esbensen Abstract Validation in chemometrics is presented using the exemplar context of multivariate calibration/prediction. A phenomenological analysis of common validation practices in data analysis and chemometrics leads to formulation of a set of generic Principles of Proper Validation (PPV), which is based on a set of characterizing distinctions: (i) Validation cannot be understood by focusing on the methods of validation only; validation must be based on full knowledge of the underlying definitions, objectives, methods, effects and consequences,which are all outlined and discussed here. (ii) Analysis of proper validation objectives implies that there is one valid paradigm only: test set validation. (iii) Contrary to much contemporary chemometric practices (and validation myths), cross-validation is shown to be unjustified in the form of monolithic application of a one-for-all procedure (segmented cross-validation) on all data sets. Within its own design and scope, cross-validation is in reality a sub-optimal simulation of test set validation, crippled by a critical sampling variance omission, as it manifestly is based on one data set only (training data set). Other re-sampling validation methods are shown to suffer from the same deficiencies. The PPV are universal and can be applied to all situations in which the assessment of performance is desired: prediction-, classification-, time series forecasting-, modeling validation. The key element of PPV is the Theory of Sampling (TOS), which allow insight into all variance generating factors, especially the so-called incorrect sampling errors, which, if not properly eliminated, are responsible for a fatal inconstant sampling bias, for which no statistical correction is possible. In the light of TOS it is shown how a second data set (test set, validation set) is critically necessary for the inclusion of the sampling errors incurred in all ,future' situations in which the validated model must perform. Logically, therefore, all one data set re-sampling approaches for validation, especially cross-validation and leverage-corrected validation, should be terminated, or at the very least used only with full scientific understanding and disclosure of their detrimental variance omissions and consequences. Regarding PLS-regression, an emphatic call is made for stringent commitment to test set validation based on graphical inspection of pertinent t,u plots for optimal understanding of the X,Y interrelationships and for validation guidance. QSAR/QSAP forms a partial exemption from the present test set imperative with no generalization potential. Copyright © 2010 John Wiley & Sons, Ltd. [source] Diagnostic assay of chromium (VI) in the ex vivo fluid of the urine of a smoker using a fluorine-doped handmade sensorJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2009Suw Young Ly Abstract A voltammetric diagnosis of a chromium (VI) ion was investigated using a fluorine-doped graphite pencil electrode. Square wave (SW) stripping working conditions were attained at a high range of 0.051,0.45,mg,L,1 and a microrange of 0.05,0.4,µg,L,1 in a 0.1,M NH4H2PO4 electrolyte solution, at a relative standard deviation of 1.68% (RSD, n=15), using 10.0,µg,L,1 Cr(VI). A fast experimental time was used only for the 120,sec SW accumulation time. An analytical detection-limit (DL) of 0.008,µg,L,1 was attained. DL appeared to be more sensitive than common voltammetric and spectrophotometric assays. The developed sensor was applied to tap water and the urine of a smoker. It was found that the methods can be applicable for in vivo fluid or medicinal diagnosis. J. Clin. Lab. Anal. 23:82,87, 2009. © 2009 Wiley-Liss, Inc. [source] Effects of multimedia and schema induced analogical reasoning on science learningJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 6 2008R.Z. Zheng Abstract The present study investigates the effects of multimedia and schema induced analogical reasoning on science learning. It involves 89 fourth grade elementary students in the north-east of the United States. Participants are randomly assigned into four conditions: (a) multimedia with analogy; (b) multimedia without analogy; (c) analogy without multimedia; and (d) non-multimedia and non-analogy. The multivariate analyses of covariance reveal significant main effects for multimedia and analogy learning as well as a significant interaction between multimedia and analogy. The findings show that schema induced analogical reasoning can significantly improve science learning and that multimedia becomes more effective when it is integrated with an instructional method such as analogy and less so when it is used only as a visual tool. The study also shows the field dependence/independence as a significant covariate that influences learners' schema induced analogical reasoning in learning. Discussions pertaining to the significance of the findings and their implications for teaching and learning are made. Suggestions for future research are included with an emphasis on developing multimedia supported analogical reasoning for science learning. [source] SELECTED ALTERNATIVES TO METHYL BROMIDE IN THE POSTHARVEST AND QUARANTINE TREATMENT OF ALMONDS AND WALNUTS: AN ECONOMIC PERSPECTIVEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2001ANTHONI F. AEGERTER Methyl bromide is a highly effective fumigant used in the postharvest and quarantine treatment of tree nuts. There will be a complete phase out in the United States of America (U.S.) of methyl bromide by 2005 according to The Montreal Protocol of 1991 with the exception of preshipment and quarantine uses as stated in the 1998 Clean Air Act. This study analyzed alternative treatment scenarios. The alternatives considered were phosphine, irradiation, and controlled atmosphere storage. Costs for each scenario were developed. Cost increases with irradiation ranged from two to fourteen times the benchmark costs for methyl bromide. Controlled atmosphere storage for both commodities had cost increases ranging from 174% to 256% over methyl bromide costs. Phosphine was used only to treat almonds. Phosphine application costs were 108% and 117% above the benchmark costs for methyl bromide. [source] Techniques and Applications of Transcatheter Embolization Procedures in Pediatric CardiologyJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2003JAMES Y. SIM M.D. Transcatheter embolization of congenital or acquired superfluous vascular structure has become routine procedures performed by interventional pediatric cardiologists. Embolization procedure is often part of a collaborative effort with cardiac surgeons to palliate complex congenital heart defect, such as in embolizing aortopulmonary collateral arteries in patient with single ventricle physiology. In other cases, the procedure is the definitive treatment as in embolizing coronary artery fistula. Pediatric cardiologists performing embolization procedures should be familiar with available technologies as well as understand the underlying cardiac anatomy and pathophysiology. This article provides a comprehensive review of presently available embolization agents and technologies. Some of the technologies are used only by interventional radiologists but may be useful to pediatric cardiologists. Specific clinical applications in pediatric cardiology are also discussed with summary of current literature. With continue advancement in transcatheter technology and operator expertise, all unwanted vascular communication should be amenable to transcatheter embolization. (J Interven Cardiol 2003;16:425,448) [source] A Review of Psychometric Properties of Feeding Assessment Tools Used in NeonatesJOURNAL OF OBSTETRIC, GYNECOLOGIC & NEONATAL NURSING, Issue 3 2008Tsu-Hsin Howe ABSTRACT Objective:, To appraise the psychometric properties of clinical feeding assessment tools used in a neonatal population. Data sources:, PubMed, OvidMedline, CINHAL, and PsycINFO databases from 1980 to 2007. Reference lists of all identified articles were also reviewed. Study selection:, Research reports written in English that utilized or validated clinical feeding assessment tools. Data extraction:, In total, 941 articles were reviewed. Seven neonatal clinical feeding assessment tools were identified and categorized into three groups: tools used for assessing either bottle-feeding or breastfeeding behaviors, tools used only for assessing bottle-feeding behaviors, and tools used only for assessing breastfeeding behaviors. Results:, The psychometric properties of none of the seven assessment tools identified were satisfactory, and the limited representativeness of the samples of the psychometric research was noted in all assessment tools identified. The Neonatal Oral-Motor Assessment Scale appeared to have been examined more thoroughly and showed more consistent results in psychometric properties than the others, despite its own limitations. Conclusions:, A psychometrically sound neonate feeding assessment tool has not yet been empirically validated. Clinicians who use these tools for clinical and research purposes should take into account this lack of evidence of psychometric soundness and interpret results of assessment with precautions. Well-designed research is needed to study the scientific integrity of these instruments for program evaluations in neonatal care. [source] Severe chronic neutropenia in Chinese children in Hong KongJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 2 2001TF Leung Objective: Severe chronic neutropenia (SCN) is a rare and heterogeneous disorder in children. The epidemiology, clinical features and outcomes of SCN in Chinese children were reviewed. Methodology: A retrospective analysis of case records was undertaken for 18 children with SCN managed during a 12-year period in a university teaching hospital in Hong Kong. Results: The median (range) age of the patients at initial presentation was 6.5 months (4 days,19 months). The initial and lowest median absolute neutrophil counts (ANC) were 0.29 × 109 /L and 0.06 × 109 /L, respectively. Patients with congenital SCN had significantly fewer neutrophils in peripheral blood at diagnosis. Only five subjects received granulocyte colony-stimulating factor (G-CSF) treatment. All children were free from serious infection on follow up for 51 months. Only one child suffered from long-term infection-related morbidity. One patient with chronic neutropenia was subsequently shown to have common variable immunodeficiency. Conclusions: Most children with SCN in our series had favourable clinical outcomes. Our results support the recommendation that G-CSF should be used only in those with recurrent or severe infections. [source] A new checkerboard panel for testing bacterial markers in periodontal diseaseMOLECULAR ORAL MICROBIOLOGY, Issue 1 2006G. Dahlén Background/aims:, Various microbiological methods have been used for testing bacterial markers for periodontitis and periodontal disease progression. Most studies have used only a limited number of well recognized bacterial species. The purpose of the present study was to evaluate the association of 13 more recently identified bacterial species in a new panel in comparison with 12 previously more recognized periodontotopathogens (,old panel') using the ,checkerboard' DNA,DNA hybridization method. Methods:, Fifty individuals were chosen who showed at least one site with a probing pocket depth of 6 mm or more (disease) and bleeding on probing and at least one site with a probing pocket depth of 3 mm and without bleeding on probing (health). One diseased and one healthy site on each individual were sampled with the paperpoint technique and the samples were processed in the checkerboard technique against deoxigenin-labeled whole genomic probes to 25 subgingival species representing 12 well recognized and 13 newly identified periodontitis associated species. Results:, Twenty-four (out of 25) species were detected more frequently in the subgingival plaque of diseased than healthy sites both at score 1 (> 104) and score 3 (> 105). A significant difference at the higher score (score 3) was noticed for all species of the old panel except for three (Streptococcus intermedius, Selenomonas noxia, and Eikenella corrodens). Of the species in the new panel only Prevotella tannerae, Filifactor alocis, and Porphyromonas endodontalis showed a statistical significant difference between diseased and healthy sites. Conclusion:, It was concluded that P. tannerae, F. alocis, and P. endodontalis should be added to the 12 species used for routine diagnostics of periodontitis-associated bacterial flora. [source] The impact of stellar oscillations on doppler velocity planet searchesMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2008S. J. O'Toole ABSTRACT We present a quantitative investigation of the effect of stellar oscillations on Doppler velocity planet searches. Using data from four asteroseismological observation campaigns, we find a power-law relationship between the noise impact of these oscillations on Doppler velocities and both the luminosity-to-mass of the target stars, and observed integration times. Including the impact of oscillation, jitter should improve the quality of Keplerian fits to Doppler velocity data. The scale of the effect these oscillations have on Doppler velocity measurements is smaller than that produced by stellar activity, but is most significant for giant and subgiant stars, and at short integration times (i.e. less than a few minutes). Such short observation times tend to be used only for very bright stars. However, since it is these very same stars that tend to be targeted for the highest precision observations, as planet searches probe to lower and lower planet masses, oscillation noise for these stars can be significant and needs to be accounted for in observing strategies. [source] Casting Out Demons: The Native Anthropologist and Healing in the HomelandNORTH AMERICAN DIALOGUE (ELECTRONIC), Issue 1 2007Tanya L. Ceja-Zamarripa This article addresses academic and social costs experienced by anthropologists studying their own ethnic group. It explores how one "native" anthropologist navigates her roles as ethnographer and insider while researching curanderismo, a religiously inflected form of ethnomedicine within increasingly secular and commercialized Mexican American urban spheres. Is academic credibility weakened because the anthropologist shares the cultural history of her/his informants? When your community entrusts you with their spiritual, emotional and social woes, do they see you as ethnographer, insider, or both? To be privy to the ritual knowledge and practices of healers and the individual struggles of clients to find respite from pain is a great responsibility as curanderismo has often been pathologized by anthropology as a "primitive" tradition used only by the ignorant and backward. Given this history, the native anthropologist must find a way to manage allegiance to her cultural as well as academic community. I suggest that doing "native" research is its own form of "exorcism," casting out demons in a field that often silences native voices and holds native anthropology in lower esteem. [source] Lactobacillus casei rhamnosus Lcr35 in children with chronic constipationPEDIATRICS INTERNATIONAL, Issue 4 2007LING-NAN BU Abstract Background: The purpose of the present paper was to evaluate the efficacy of probiotics (Lactobacillus casei rhamnosus, Lcr35) for treating children with chronic constipation and to compare its effect with magnesium oxide (MgO) and placebo. Methods: This double-blind placebo-controlled, randomized study enrolled 45 children under 10 years old with chronic constipation. They were randomly assigned to receive Lcr35 (8 × 108 c.f.u./day; n = 18), MgO (50 mg/kg/day; n = 18), or placebo (n = 9) orally twice daily for 4 weeks. Lactulose use (1 mL/kg per day) was allowed when no stool passage for 3 days was noted. Glycerin enema was used only when no defecation was noted for >5 days or abdominal pain was suffered due to stool impaction. Bacterial cultures of stool were performed before and after treatment to evaluate the change of intestinal flora. Comparisons of the frequency of defecation, consistency of stool and the use of lactulose or enema during the period of treatment were made among the three groups. Results: The patients who received MgO or probiotics had a higher defecation frequency (P = 0.03), higher percentage of treatment success (P = 0.01), less use of glycerin enema (P = 0.04) and less hard stool (P = 0.01) than the placebo group. There was no significant difference between MgO and probiotic groups in the aforementioned comparisons. The first effect of MgO (second week) on constipation was slightly earlier than that of probiotic (second to third week). Abdominal pain occurred less frequently in the probiotic group than in both the MgO and the placebo groups (P = 0.03). There was no statistically significant difference among the three groups in the use of lactulose, episodes of fecal soiling, and change of appetite. No adverse effect was noted in probiotic and placebo groups. Only one patient in the MgO group suffered from mild diarrhea. Conclusion: Lcr35 was effective in treating children with chronic constipation. There is no statistically significant difference in efficacy between MgO and Lcr35, but less abdominal pain occurred when using Lcr35. Study with larger case number and longer follow up is needed in the future. [source] What can pest management learn from laboratory animal ethics?PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 3 2010James Yeates Abstract There remains a lack of a clear overarching policy framework for decision-making in pest control programmes. In comparison, ethical principles have been extensively developed for scientific procedures, such as those underlying the UK's Animals (Scientific Procedures) Act 1986. This paper assesses the extent to which the principles and methodology underlying the act and secondary guidance could be used to provide principles of rodent management. Useful principles include that any programme has a legitimate purpose; that methods are used only if the harms are outweighed by the benefits; that harms are minimised by refinement, replacement and reduction and that there is personal responsibility. The usefulness and implications for pest control of each principle and the overall approach are discussed. Copyright © 2009 Society of Chemical Industry [source] Getting the fundamentals wrong: woes of public,private partnerships in solid waste collection in three Ghanaian citiesPUBLIC ADMINISTRATION & DEVELOPMENT, Issue 3 2004Nicholas Awortwi Until over a decade ago, concerted efforts at involving private agents to deliver solid waste collection services did not feature in local government's (LG's) policies and practices in Ghana. The LGs had over the years directly delivered the services with their labour, materials and equipment. The purpose of entering into partnerships with private contractors was to improve service delivery. This comes at a time when the private sector is generally viewed as more efficient and effective than the public sector. There is abundant literature on potential benefits of private sector participation in public service delivery; yet, figures of efficiency gains are often accepted without challenge. More advantages but fewer disadvantages are cited and anecdotal evidence is used only to illustrate successful applications of the concept of public,private partnerships (PPPs). Using research data from three cities (Accra, Kumasi and Tema) in Ghana, this article exposes the contrast between policy expectations and outcomes of PPPs. The article argues that simply turning over public service delivery to private agents without ensuring that the fundamentals that make them successful are put in place leads to a worse situation than portrayed in literature about the benefit of PPPs. Copyright © 2004 John Wiley & Sons, Ltd. [source] A comparison of muscle- and scale-derived ,13C and ,15N across three life-history stages of Atlantic salmon, Salmo salarRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 18 2008R. Niloshini Sinnatamby Stable isotope signatures were obtained from paired scale and muscle tissue samples from smolt, post-smolt and one-sea-winter adult Atlantic salmon (Salmo salar). Post-smolt and adult scales were separated into central and outer (marine) portions with analyses carried out on the marine growth section of both life-history stages and the central portion for the adult scales. Muscle and scale ,13C and ,15N signatures were assessed (1) to determine whether a linear relationship exists between tissue types, (2) to determine if a constant offset exists between tissue signatures across all life-history stages, and (3) to evaluate whether underplating imparts a significant bias to life-history scale segments that would preclude their use in retrospective analyses of any ontogenetic dietary changes between life-history stages. Significant correlations were found to exist between muscle and scale stable isotope signatures obtained from smolts (,13C and ,15N) and adults (,15N). Both the muscle and the scale signatures captured the dietary shift associated with the transition from freshwater to the marine environment. Post-smolt and adult scales were depleted relative to muscle tissue, which may be attributed to isotopic differences in amino acid composition between muscle and scale tissues. The results suggest that scales may better represent dietary carbon sources because they are not influenced by lipid dynamics. The scale, however, appears less responsive to short-term shifts in diet relative to muscle and, therefore, must be used only to infer seasonally integrated dietary patterns for slow-growing life-history stages. Copyright © 2008 John Wiley & Sons, Ltd. [source]
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