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Terms modified by Calculating Selected AbstractsReactivity in LaGaO3/Ni and CeO2/Ni SystemsFUEL CELLS, Issue 2 2006N. Solak Abstract The reactivity in CeO2/Ni and LaGaO3/Ni systems, which are constituents of intermediate temperature solid oxide fuel cell (IT-SOFC) anodes, has been investigated both computationally and experimentally. The CALPHAD-method (CALculating of PHAse Diagrams), employing BINGSS and THERMOCALC software, was used to obtain a self-consistent set of Gibbs energy functions describing the systems. Interactions in the LaGaO3/Ni system were predicted using a thermodynamic database developed for the La-Ga-Ni-O system. Similarly, to analyze the CeO2/Ni system, the Ce-Ni-O ternary phase diagram was calculated using known thermodynamic data for binary Ce-O, Ni-O, and Ce-Ni systems. The experimental work was designed based on the calculated phase diagrams. While the La-Ga-Ni-O system experiments were conducted in air, the Ce-Ni-O system was also investigated in a reducing atmosphere. The calculated Ce-Ni-O diagram is in good agreement with the experimental results. It has been found that NiO does not react with CeO2. Extended solid solutions of La(Ga,Ni)O3, La2(Ni,Ga)O4, and La4(Ni,Ga)3O10 were found in the La-Ga-Ni-O system. Additionally, the compound LaNiGa11O19, with magnetoplumbite-type structure, has been found, which has not been reported in the literature so far. It is concluded that La2NiO4 is not chemically compatible, as a cathode material, with the LSGM electrolyte. [source] Extinction debt on oceanic islandsECOGRAPHY, Issue 2 2010Kostas A. Triantis Habitat destruction is the leading cause of species extinctions. However, there is typically a time-lag between the reduction in habitat area and the eventual disappearance of the remnant populations. These "surviving but ultimately doomed" species represent an extinction debt. Calculating the magnitude of such future extinction events has been hampered by potentially inaccurate assumptions about the slope of species,area relationships, which are habitat- and taxon-specific. We overcome this challenge by applying a method that uses the historical sequence of deforestation in the Azorean Islands, to calculate realistic and ecologically-adjusted species,area relationships. The results reveal dramatic and hitherto unrecognized levels of extinction debt, as a result of the extensive destruction of the native forest:>95%, in<600,yr. Our estimations suggest that more than half of the extant forest arthropod species, which have evolved in and are dependent on the native forest, might eventually be driven to extinction. Data on species abundances from Graciosa Island, where only a very small patch of secondary native vegetation still exists, as well as the number of species that have not been found in the last 45,yr, despite the extensive sampling effort, offer support to the predictions made. We argue that immediate action to restore and expand native forest habitat is required to avert the loss of numerous endemic species in the near future. [source] Calculating the ROI on internal communicationsEMPLOYMENT RELATIONS TODAY, Issue 1 2002Robert W. Sprague First page of article [source] A non-iterative derivation of the common plane for contact detection of polyhedral blocksINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2008Shu-Wei Chang Abstract A non-iterative derivation for finding the common plane between two polyhedral blocks is presented. By exploiting geometric relations between the normal of a plane and the closest vertex on a block, the common plane can be resolved without resorting to an iterative method. To facilitate derivations, normals in half-space are decomposed into finite subsets in which each subset corresponds to the same closest vertex on a block. The gap function, originally dependent on the normal and the two closest vertices, becomes a function of the normal only. To compute the gap for a given normal subset, the maximum theorem and the maximum projection theorem are introduced. The maximum theorem reduces finding the maximum in a subset to its boundary. Calculating the gap in 2D in a given subset thus reduces to checking two inner products. The maximum projection theorem further reduces finding the maximum on a 3D boundary to an explicit form. Three numerical examples are used to demonstrate the accuracy and efficiency of the proposed scheme. The example in which the blocks are in contact further shows the existence of a local maximum while calculating the gap and illustrates the potential deficiencies in using the Cundall's iterative scheme. Copyright © 2007 John Wiley & Sons, Ltd. [source] Effect of non-response bias in pressure ulcer prevalence studiesJOURNAL OF ADVANCED NURSING, Issue 2 2006Nils Lahmann BA RN Aim., This paper reports a study to determine the prevalence of pressure ulcers in German hospitals and nursing homes for national and international comparison, and analyses the influence of non-response bias. Background., Outcome rates are often used to evaluate provider performance. The prevalence of pressure ulcers is seen as a possible parameter of outcome healthcare quality. However, the results from different pressure ulcer prevalence studies cannot be compared, because there is no standardized methodology and terminology. Observed and published prevalence rates may reflect variations in quality of care, but differences could also relate to differences in case-mix or to random variation. Methods., A point prevalence survey was carried out for 2002 and 2003 using data from 21,574 patients and residents in 147 different kinds of institutions throughout Germany. Participation rates and reasons for not participating in the study were documented. Non-responders were considered in different calculations to show the range of possible prevalence rate for a hypothetic 100% participation. Results., In 2002 and 2003, the calculated prevalence rate (among participating persons at risk) in hospitals was 25·1% and 24·2% respectively, while in nursing homes it was 17·3% and 12·5% respectively. Non-response varied from 15·1% to 25·1%. The majority of non-responders in hospitals and nursing homes had not been willing to participate in the study. Based on different assumptions about the characteristics of the non-responders, we calculated minimum and maximum prevalence rates as if 100% participation was achieved. Conclusions., Calculating the non-response bias of prevalence rates is an inconvenient but necessary thing to do because its influence on calculated prevalence rates was high in this study. High participation rates in clinical studies will minimize non-response bias. If non-response cannot be avoided, the formula provided will help researchers calculate possible minimum and maximum prevalence rates for the total sample of both the responding and non-responding groups. [source] Forecast covariances in the linear multiregression dynamic modelJOURNAL OF FORECASTING, Issue 2 2008Catriona M. Queen Abstract The linear multiregression dynamic model (LMDM) is a Bayesian dynamic model which preserves any conditional independence and causal structure across a multivariate time series. The conditional independence structure is used to model the multivariate series by separate (conditional) univariate dynamic linear models, where each series has contemporaneous variables as regressors in its model. Calculating the forecast covariance matrix (which is required for calculating forecast variances in the LMDM) is not always straightforward in its current formulation. In this paper we introduce a simple algebraic form for calculating LMDM forecast covariances. Calculation of the covariance between model regression components can also be useful and we shall present a simple algebraic method for calculating these component covariances. In the LMDM formulation, certain pairs of series are constrained to have zero forecast covariance. We shall also introduce a possible method to relax this restriction. Copyright © 2008 John Wiley & Sons, Ltd. [source] Calculating the frequency of serious reportable adverse events and hospital-acquired conditionsJOURNAL OF HEALTHCARE RISK MANAGEMENT, Issue 1 2010CPHRM, DFASHRM, MT(ASCP), Robert F. Bunting Jr. MSA The Centers for Medicare and Medicaid Services (CMS) mandated that Medicare Advantage Organizations (MAOs) begin reporting the number of serious reportable adverse events and hospital-acquired conditions received on Medicare claims. There are additional state mandates and health insurance plan requirements. The author provides an analysis of the reporting methodology and proposes an alternative approach using rate-based formulas that would yield information that is more useful. [source] CLINICAL SCHOLARSHIP: Systematic Review of Educational Interventions for Improving Advance Directive CompletionJOURNAL OF NURSING SCHOLARSHIP, Issue 3 2010Christine R. Durbin RN Abstract Purpose: To systematically analyze evidence about the outcome and percent of newly completed ADs, focusing on the effectiveness of (a) types of educational interventions versus controls and (b) one educational intervention over another. Design: Systematic review of literature based on Cochrane review criteria. Methods: Twelve randomized and four nonrandomized studies were selected from the nursing, medical, and social work literature that met the following criteria: described educational interventions, provided information to calculate the percent of newly completed ADs as an outcome, and published between 1991 and 2009. The review focused primarily on randomized studies. Reviewers calculated the percent of newly completed ADs by determining the number of subjects per group without an AD at baseline and the percentage of those who then completed one by the end of the studies. Findings: Findings were inconsistent regarding all types of educational interventions studied versus controls. Sufficient evidence exists to conclude that combined written and verbal educational interventions were more effective than single written interventions in increasing the percent of newly completed ADs in adult clinic outpatients and hospitalized elderly. Conclusions: Calculating the percent of newly completed ADs was successful in allowing for study result comparisons. Overall, the evidence base regarding the effectiveness of single or combined educational interventions in increasing AD completion is weak. Randomized studies with diverse samples should be conducted against controls before more studies comparing interventions are undertaken. Clinical Relevance: This article provides nurses with a summary of research related to educational interventions and AD completion and identifies where future study is needed. [source] Empirical Equation for Calculating the Density of Oxide GlassesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2010Seiji Inaba The density of oxide glass including silicate, borate, phosphate, tellurite, and germanate glasses were measured using the Archimedes method. On the assumption that the ionic packing ratio is approximately a constant independent of chemical composition, an empirical equation for estimating the density from chemical composition was proposed. The calculated values are in reasonable agreement with the corresponding measured ones. [source] Charge carrier dissociation and recombination in polymer solar cellsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 12 2009Carsten Deibel Abstract In polymer:fullerene solar cells, the origin of the losses in the field-dependent photocurrent is still controversially debated. We contribute to the ongoing discussion by performing photo-induced charge extraction measurements on poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C61 butyric acid methyl ester solar cells in order to investigate the processes ruling charge carrier decay. Calculating the drift length of photogenerated charges, we find that polaron recombination is not limiting the photocurrent for annealed devices. Additionally, we applied Monte Carlo simulations on blends of conjugated polymer chain donors with acceptor molecules in order to gain insight into the polaron pair dissociation. The dissociation yield turns out to be rather high, with only a weak field dependence. With this complementary view on dissociation and recombination, we stress the importance of accounting for polaron pair dissociation, polaron recombination as well as charge extraction when considering the loss mechanisms in organic solar cells. [source] Reference ranges for umbilical vein blood flow in the second half of pregnancy based on longitudinal dataPRENATAL DIAGNOSIS, Issue 2 2005Ganesh Acharya Abstract Objectives To construct new reference ranges for serial measurements of umbilical vein (UV) blood flow. Methods Prospective longitudinal study of blood flow velocities and diameter of the UV measured at four-weekly intervals during 19 to 42 weeks' gestation in 130 low-risk singleton pregnancies. Regression models and multilevel modeling were used to construct the reference ranges. Results On the basis of 511 sets of longitudinal observations, we established new reference percentiles of UV diameter, blood flow velocities, volume flow, and blood flow normalized for fetal weight and abdominal circumference. They reflected some of the developmental patterns of previous cross-sectional studies, but with important differences, particularly near term. The UV blood flow showed a continuous increase until term, whereas the flow normalized per unit fetal weight, a corresponding reduction. Calculating the blood flow on the basis of intensity-weighted mean velocity or 0.5 of the maximum velocity gave almost interchangeable results for most fetuses. Conclusion New reference ranges for UV blood flow based on longitudinal observations appear slightly different from cross-sectional studies, and should be more appropriate for serial evaluation of fetal circulation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Calculation of Posterior Probabilities for Bayesian Model Class Assessment and Averaging from Posterior Samples Based on Dynamic System DataCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2010Sai Hung Cheung Because of modeling uncertainty, a set of competing candidate model classes may be available to represent a system and it is then desirable to assess the plausibility of each model class based on system data. Bayesian model class assessment may then be used, which is based on the posterior probability of the different candidates for representing the system. If more than one model class has significant posterior probability, then Bayesian model class averaging provides a coherent mechanism to incorporate all of these model classes in making probabilistic predictions for the system response. This Bayesian model assessment and averaging requires calculation of the evidence for each model class based on the system data, which requires the evaluation of a multi-dimensional integral involving the product of the likelihood and prior defined by the model class. In this article, a general method for calculating the evidence is proposed based on using posterior samples from any Markov Chain Monte Carlo algorithm. The effectiveness of the proposed method is illustrated by Bayesian model updating and assessment using simulated earthquake data from a ten-story nonclassically damped building responding linearly and a four-story building responding inelastically. [source] Horizontal Roadway Curvature Computation Algorithm Using Vision TechnologyCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 2 2010Yichang (James) Tsai However, collecting such data is time-consuming, costly, and dangerous using traditional, manual surveying methods. It is especially difficult to perform such manual measurement when roadways have high traffic volumes. Thus, it would be valuable for transportation agencies if roadway curvature data could be computed from photographic images taken using low-cost digital cameras. This is the first article that develops an algorithm using emerging vision technology to acquire horizontal roadway curvature data from roadway images to perform roadway safety assessment. The proposed algorithm consists of four steps: (1) curve edges image processing, (2) mapping edge positions from an image domain to the real-world domain, (3) calibrating camera parameters, and (4) calculating the curve radius and center from curve points. The proposed algorithm was tested on roadways having various levels of curves and using different image sources to demonstrate its capability. The ground truth curvatures for two cases were also collected to evaluate the error of the proposed algorithm. The test results are very promising, and the computed curvatures are especially accurate for curves of small radii (less than 66 m/200 ft) with less than 1.0% relative errors with respect to the ground truth data. The proposed algorithm can be used as an alternative method that complements the traditional measurement methods used by state DOTs to collect roadway curvature data. [source] Interaction of exchange and differential relaxation in the saturation recovery behavior of the binary spin-bath model for magnetization transferCONCEPTS IN MAGNETIC RESONANCE, Issue 4 2006Gunther Helms Abstract Most closed-form analytical solutions of the binary spin-bath are difficult to interpret in terms of underlying physics. The key notions are the presence of a kinetic and a thermal equilibrium and that the time course of saturation recovery under conditions of fast exchange can be understood as conjoint relaxation and lossless transfer. By introducing a suitable parameter, it is shown how exchange and differential relaxation counteract each other: the amount of transferred saturation (transfer term) is altered and the kinetic equilibrium appears slightly disturbed (difference term). Although the factorization formally represents the general solution of saturation recovery in the binary spin-bath, this interpretation applies only to the case of fast exchange and slow relaxation. By calculating the set of parameters for a wide range of hypothetical relaxation rates, it was shown that the difference term is crucial to describe the transition to the slow-exchange limit. The transfer term vanishes as the two pools appear decoupled in this approximation. © 2006 Wiley Periodicals, Inc. Concepts Magn Reson Part A 28A: 291,298, 2006. [source] Analysis of b -value calculations in diffusion weighted and diffusion tensor imagingCONCEPTS IN MAGNETIC RESONANCE, Issue 1 2005Daniel Güllmar Abstract Diffusion weighted imaging has opened new diagnostic possibilities by using microscopic diffusion of water molecules as a means of image contrast. The directional dependence of diffusion has led to the development of diffusion tensor imaging, which allows us to characterize microscopic tissue geometry. The link between the measured NMR signal and the self-diffusion tensor is established by the so-called b matrices that depend on the gradient's direction, strength, and timing. However, in the calculation of b -matrix elements, the influence of imaging gradients on each element of the b matrix is often neglected. This may cause errors, which in turn leads to an incorrect extraction of diffusion coefficients. In cases where the imaging gradients are high (high spatial resolution), these errors may be substantial. Using a generic pulsed gradient spin-echo (PGSE) imaging sequence, the effects of neglecting the imaging gradients on the b -matrix calculation are demonstrated. By measuring an isotropic phantom with this sequence it can be analytically as well as experimentally shown that large deviations in single b -matrix elements are generated. These deviations are obtained by applying the diffusion weighting in the readout direction of the imaging dimension in combination with relatively large imaging gradients. The systematic errors can be avoided by a full b -matrix calculation considering all the gradients of the sequence or by generating cross-term free signals using the geometric average of two diffusion weighted images with opposite polarity. The importance of calculating the exact b matrices by the proposed methods is based on the fact that more precise diffusion parameters are obtained for extracting correct property maps, such as fractional anisotropy, volume ratio, or conductivity tensor maps. © 2005 Wiley Periodicals, Inc. Concepts Magn Reson Part A 25A: 53,66, 2005 [source] A Grid-enabled problem-solving environment for advanced reservoir uncertainty analysisCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 18 2008Zhou Lei Abstract Uncertainty analysis is critical for conducting reservoir performance prediction. However, it is challenging because it relies on (1) massive modeling-related, geographically distributed, terabyte, or even petabyte scale data sets (geoscience and engineering data), (2) needs to rapidly perform hundreds or thousands of flow simulations, being identical runs with different models calculating the impacts of various uncertainty factors, (3) an integrated, secure, and easy-to-use problem-solving toolkit to assist uncertainty analysis. We leverage Grid computing technologies to address these challenges. We design and implement an integrated problem-solving environment ResGrid to effectively improve reservoir uncertainty analysis. The ResGrid consists of data management, execution management, and a Grid portal. Data Grid tools, such as metadata, replica, and transfer services, are used to meet massive size and geographically distributed characteristics of data sets. Workflow, task farming, and resource allocation are used to support large-scale computation. A Grid portal integrates the data management and the computation solution into a unified easy-to-use interface, enabling reservoir engineers to specify uncertainty factors of interest and perform large-scale reservoir studies through a web browser. The ResGrid has been used in petroleum engineering. Copyright © 2008 John Wiley & Sons, Ltd. [source] Descriptive epidemiology of anotia and microtia, Hawaii, 1986,2002CONGENITAL ANOMALIES, Issue 4 2005Mathias B. Forrester ABSTRACT The objective of this investigation was to describe the epidemiology of anotia and microtia with respect to various factors. The cases studied were all infants and fetuses with anotia or microtia identified by a population-based birth defects registry in Hawaii. The anotia and microtia rates were determined for selected factors and comparisons made among the subgroups by calculating the rate ratio (RR) and 95% confidence interval (CI). A total of 120 cases were identified, for a rate of 3.79 per 10 000 live births. The anotia and microtia rate increased during 1986,2002, although the trend was not significant (P = 0.715). Of 49 specific structural birth defects examined, four were found to be significantly more common in the presence of anotia and microtia. When compared with Caucasians, the anotia and microtia rates were higher among Far East Asians (RR 1.79, 95% CI 0.89,3.68), Pacific Islanders (RR 2.26, 95% CI 1.24,4.32), and Filipinos (RR 2.34, 95% CI 1.23,4.64). The defects were less common among females (RR 0.64, 95% CI 0.43,0.93) and more common with multiple birth (RR 3.72, 95% CI 1.66,7.33), birth weight <,2500 g (RR 3.35, 95% CI 2.04,5.30), and gestational age <38 weeks (RR 2.27, 95% CI 1.49,3.40). In conclusion, the rate for anotia and microtia increased in Hawaii during the study period. The rates for only a few structural birth defects were substantially greater than expected in association with anotia and microtia. Anotia and microtia rates varied significantly according to maternal race/ethnicity, infant sex, plurality, birth weight, and gestational age. [source] The Efficacy of Curettage in Delineating Margins of Basal Cell Carcinoma Before Mohs Micrographic SurgeryDERMATOLOGIC SURGERY, Issue 9 2003Désirée Ratner MD Background. Curettage may be helpful as a preliminary step to outline the gross subclinical extensions of high-risk basal cell carcinomas (BCCs) before the first stage of Mohs micrographic surgery. Although many Mohs surgeons use curettage in the Mohs surgical setting, no prospective studies have as yet been performed that demonstrate the efficacy of curettage in delineating tumor margins before Mohs surgery. Objective. To document the efficacy of curettage in delineating BCC margins before Mohs micrographic surgery. Methods. This was a prospective evaluation of 599 patients with biopsy-proven BCCs treated with Mohs surgery. The preoperative dimensions of each tumor, the curetted dimensions before the first surgical stage, the proposed excisional margins before each surgical stage, and the final defect dimensions after each surgical stage were measured. The maximum curetted margin around each tumor was calculated and compared with typical Mohs excisional margins of 1, 2, 3, and 4 mm. A hypothetical 1-, 2-, 3-, or 4-mm excisional margin was added to the preoperative X and Y dimensions of each tumor, and the actual final defect sizes were compared with the hypothetical final defect sizes to determine whether an additional surgical stage would have been needed had curettage not been performed. The amount of tissue stretch occurring after specimen removal was calculated to determine whether tissue stretch falsely elevated the number of instances in which an additional surgical stage would have been needed had curettage not been performed. Results. The curetted margin around the observed extent of each tumor exceeded 1 mm in 87.6% of cases, 2 mm in 47.1% of cases, 3 mm in 19.7% of cases, and 4 mm in 5.7% of cases. The mean curetted margin was 1.7 mm. Taking a 1-mm margin in the first stage of Mohs surgery without first performing curettage would have necessitated an extra surgical stage in 99.2% of cases, whereas taking a 2-, 3-, or 4-mm margin would have necessitated an extra surgical stage in 93.0%, 88.1%, and 49.4% of cases, respectively. After calculating and eliminating the effects of tissue stretch, it was found that a 1-mm excisional margin taken in the first stage of Mohs surgery without first performing curettage would have necessitated an extra surgical stage in 99.0% of the cases. Taking a 2-, 3-, or 4-mm margin would have necessitated an extra surgical stage in 87.5%, 57.9%, and 29.5% of cases, respectively. Conclusion. Careful debulking and palpation with the curette significantly reduce the number of Mohs surgical stages required for BCC clearance. Even after taking the effects of tissue stretch into consideration, a significant proportion of tumors would still require an additional stage for tumor clearance without aggressive presurgical curettage. [source] Posttranslational regulation of BCL2 levels in cerebellar granule cells: A mechanism of neuronal survivalDEVELOPMENTAL NEUROBIOLOGY, Issue 13 2009Laura Lossi Abstract Apoptosis can be modulated by K+ and Ca2+ inside the cell and/or in the extracellular milieu. In murine organotypic cultures, membrane potential-regulated Ca2+ signaling through calcineurin phosphatase has a pivotal role in development and maturation of cerebellar granule cells (CGCs). P8 cultures were used to analyze the levels of expression of B cell lymphoma 2 (BCL2) protein, and, after particle-mediated gene transfer in CGCs, to study the posttranslational modifications of BCL2 fused to a fluorescent tag in response to a perturbation of K+/Ca2+ homeostasis. There are no changes in Bcl2 mRNA after real time PCR, whereas the levels of the fusion protein (monitored by calculating the density of transfected CGCs under the fluorescence microscope) and of BCL2 (inWestern blotting) are increased. After using a series of agonists/antagonists for ion channels at the cell membrane or the endoplasmic reticulum (ER), and drugs affecting protein synthesis/degradation, accumulation of BCL2 was related to a reduction in posttranslational cleavage by macroautophagy. The ER functionally links the [K+]e and [Ca2+]i to the BCL2 content in CGCs along two different pathways. The first, triggered by elevated [K+]e under conditions of immaturity, is independent of extracellular Ca2+ and operates via IP3 channels. The second leads to influx of extracellular Ca2+ following activation of ryanodine channels in the presence of physiological [K+]e, when CGCs are maintained in mature status. This study identifies novel mechanisms of neuroprotection in immature and mature CGCs involving the posttranslational regulation of BCL2. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009 [source] Endocervical curetting vs. endocervical brushing as case finding methods,DIAGNOSTIC CYTOPATHOLOGY, Issue 5 2006John A. Maksem M.D. Abstract This paper focuses on the performance of endocervical curettage (ECC) and intensive endocervical brushing (ECB) (comprising two or more brushings of the endocervix with liquid-based cytology and cell-block examination) in the course of colposcopic examination for abnormal gynecological cytology. To assess their relative effectiveness in disease detection, we reviewed the outcomes of 1,824 colposcopic biopsy collections from women who had an index cytology diagnosis of LSIL or higher. Our intent was to gauge the relative success of ECC and ECB as case-finding procedures in relation to (1) the original cytological diagnosis and (2) the highest (most abnormal) histological diagnosis of the colposcopy study. Our purpose was to determine whether ECB could effectively replace ECC. One thousand five hundred and seven cases of LSILs or higher cases included an ECC along with two or more colposcopic biopsies and 317 cases included an ECB. ECBs were collected into a liquid fixative and processed as both cytology and cell-block specimens; whereas, ECCs were processed according to standard histological techniques. We found that intensive ECB recapitulates the highest diagnosis of the colposcopy study about 5,8 times as often as that of ECC. Moreover, when calculating the proportion of positive outcomes, we found that cases examined with biopsy and ECC discovered fewer women with CIN 2 or higher among both LSIL and HSIL index cytologies as compared with those of cases examined with biopsy and ECB (9.2% vs. 16.8% for LSIL and 63.7% vs. 72.2% for HSIL cases); and, more negative outcomes were seen among women evaluated with biopsy plus ECC than those with biopsy plus ECB (11.3% vs. 8.1% for LSIL and 4.7% vs. 1.4% for HSIL cases). Our findings suggest that the colposcopic study is optimized when it is performed in conjunction with ECB as opposed to ECC, and that intensive ECB may be superior to ECC. Diagn. Cytopathol. 2006; 34:313,316. © 2006 Wiley-Liss, Inc. [source] Biodiversity and distribution of epibiontic communities on Caridina ensifera (Crustacea, Decapoda, Atyidae) from Lake Poso: comparison with another ancient lake system of Sulawesi (Indonesia)ACTA ZOOLOGICA, Issue 2 2010Gregorio Fernandez-Leborans Abstract Fernandez-Leborans, G. and von Rintelen, K. 2010. Biodiversity and distribution of epibiontic communities on Caridina ensifera (Crustacea, Decapoda, Atyidae) from Lake Poso: comparison with another ancient lake system of Sulawesi (Indonesia). , Acta Zoologica (Stockholm) 91: 163,175 The epibiont communities of the shrimp Caridina ensifera, endemic to Lake Poso (Sulawesi, Indonesia), were analysed. Most of the epibiont species were ciliated protozoa belonging to three suctorian genera (Acineta, Podophrya and Spelaeophrya), three peritrich genera (Zoothamnium, Vorticella and Cothurnia), and a haptorid genus (Amphileptus). There was also a rotifer epibiont of the genus Embata. Epibionts were identified to species level. There were 14 to 1114 epibionts per shrimp. The distribution of the epibiont species on the surface of the basibiont was recorded, calculating the number on the different colonized individuals of C. ensifera. The most abundant species, Zoothamnium intermedium and Acineta sulawesiensis, were also the most widely distributed. There was a significant difference between the spatial distributions of the different epibiont species. The analysis of the number of the epibiont species throughout the anteroposterior axis of the shrimp showed a gradient from the anterior to the posterior end of the body. Data from Lake Poso were compared with those of the Malili lake system (Sulawesi), obtained from its endemic shrimp, Caridina lanceolata. Lake Poso had the highest mean diversity, while Lake Mahalona showed the highest maximum diversity. All lakes were correlated with respect to the mean number of epibionts on the anatomical units of the shrimp, which showed a similar general distribution. The distributions of the different epibiont species were compared between the lakes. The possible adaptations of the epibionts as well as the colonization patterns were discussed. From the statistical results and the analysis of the distributions, we propose that in these communities epibiont species have a pattern of colonization in which they follow a behaviour as a whole; each species has a differential distribution, with the species occupying the available substratum with the particular requirements of each functional group, but there is a trend towards maintaining an equilibrium among species and groups, compensating for diversity and number of individuals. In all lakes there was an epibiont distribution model comprising the maintenance of an anteroposterior axis gradient, which was supported by the fluctuation in diversity and number of individuals of the different functional groups of epibiont species. The functional role of the different groups of species seems to tend towards sustainability with little global variation among the lakes. [source] Using Design Effects From Previous Cluster Surveys to Guide Sample Size Calculation in Emergency SettingsDISASTERS, Issue 2 2006Reinhard Kaiser Abstract A good estimate of the design effect is critical for calculating the most efficient sample size for cluster surveys. We reviewed the design effects for seven nutrition and health outcomes from nine population-based cluster surveys conducted in emergency settings. Most of the design effects for outcomes in children, and one-half of the design effects for crude mortality, were below two. A reassessment of mortality data from Kosovo and Badghis, Afghanistan revealed that, given the same number of clusters, changing sample size had a relatively small impact on the precision of the estimate of mortality. We concluded that, in most surveys, assuming a design effect of 1.5 for acute malnutrition in children and two or less for crude mortality would produce a more efficient sample size. In addition, enhancing the sample size in cluster surveys without increasing the number of clusters may not result in substantial improvements in precision. [source] The effect of single vegetation elements on wind speed and sediment transport in the Sahelian zone of Burkina FasoEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2007J. K. Leenders Abstract Soil loss caused by wind erosion is a widespread phenomenon in the Sahelian zone of West Africa. According to Sahelian farmers, scattered vegetation standing in amongst the crop has the potential for a wind erosion control strategy. This study was conducted to study the effect of single vegetation elements on the pattern of average wind speed and sediment transport. This was done by two experiments that were carried out during the rainy seasons of 2002 and 2003 in north Burkina Faso, West Africa. Wind speeds were measured using three sonic anemometers, at a sampling frequency of 16 Hz. Sediment transport was determined by calculating the mass fluxes from 17 MWAC catchers. In this study, a shrub was defined as a vegetation element with branches until ground and a tree as a vegetation element with a distinctive trunk below a canopy. Behind shrubs wind speed near the soil surface was reduced up to approximately seven times the height of the shrub. The observed reduction in wind speed in the area where wind speed was reduced was 15 per cent on average. At the sides of the shrub, wind speed was increased, by on average 6 per cent. As the area of increase in wind speed is one-third of the area of decrease in wind speed, the net effect of a shrub is a reduction in wind speed. A similar pattern was visible for the pattern of sediment transport around a shrub. Downwind of a shrub, sediment transport was diminished up to seven times the height of the shrub. Probably most of this material was trapped by the shrub. Trees showed a local increase of wind around the trunk, which is expected to relate to an increase in sediment transport around the trunk. Mass flux measurements of sediment transport were not made, but visual observations in the field substantiate this. Behind the canopy of a tree, a tree acts similarly to a shrub regarding its effects on average wind speed, but as a tree is generally a larger obstacle than a shrub the extent of this effect is larger than for shrubs. Thus, whereas shrubs are more effective than trees regarding their direct effect on soil loss by trapping sand particles near the soil surface, trees are more effective in affecting soil loss indirectly by reducing the wind speed downwind more effectively than shrubs. Therefore, to reduce soil loss in an area, the presence of both trees and shrubs is crucial. Copyright © 2007 John Wiley & Sons, Ltd. [source] A model for the 3D kinematic interaction analysis of pile groups in layered soilsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 11 2009Francesca Dezi Abstract The paper presents a numerical model for the analysis of the soil,structure kinematic interaction of single piles and pile groups embedded in layered soil deposits during seismic actions. A finite element model is considered for the pile group and the soil is assumed to be a Winkler-type medium. The pile,soil,pile interaction and the radiation problem are accounted for by means of elastodynamic Green's functions. Condensation of the problem permits a consistent and straightforward derivation of both the impedance functions and the foundation input motion, which are necessary to perform the inertial soil,structure interaction analyses. The model proposed allows calculating the internal forces induced by soil,pile and pile-to-pile interactions. Comparisons with data available in literature are made to study the convergence and validate the model. An application to a realistic pile foundation is given to demonstrate the potential of the model to catch the dynamic behaviour of the soil,foundation system and the stress resultants in each pile. Copyright © 2009 John Wiley & Sons, Ltd. [source] Tangential-projection algorithm for manifold representation in unidentifiable model updating problemsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 4 2002Lambros S. Katafygiotis Abstract The problem of updating a structural model and its associated uncertainties by utilizing structural response data is addressed. In an identifiable case, the posterior probability density function (PDF) of the uncertain model parameters for given measured data can be approximated by a weighted sum of Gaussian distributions centered at a number of discrete optimal values of the parameters at which some positive measure-of-fit function is minimized. The present paper focuses on the problem of model updating in the general unidentifiable case for which certain simplifying assumptions available for identifiable cases are not valid. In this case, the PDF is distributed in the neighbourhood of an extended and usually highly complex manifold of the parameter space that cannot be calculated explicitly. The computational difficulties associated with calculating the highly complex posterior PDF are discussed and a new adaptive algorithm, referred to as the tangential-projection (TP) algorithm, allowing for an efficient approximate representation of the above manifold and the posterior PDF is presented. Using this approximation, expressions for calculating the uncertain predictive response are established. A numerical example involving noisy data is presented to demonstrate the proposed method. Copyright © 2002 John Wiley & Sons, Ltd. [source] The impact of eliminating the global illicit cigarette trade on health and revenueADDICTION, Issue 9 2010Luk Joossens ABSTRACT Aims The purpose of this study was to update global estimates of the illicit cigarette trade, based on recent data, and estimate how many lives could be saved by eliminating it and how much revenue governments would gain. Data sources and methods Our estimates of illicit market share are based on formal and informal sources. Our method for estimating the effect of eliminating the illicit trade on tobacco related deaths is based on West et al. with some minor modifications, and involves calculating the size of the illicit cigarette trade; the effect of eliminating it on the price of cigarettes and thus on consumption; the revenue governments are losing because of it; and the number of tobacco-related premature deaths that would be avoided if this illicit trade were eliminated. Results According to available estimates, the size of the illicit trade varies between countries from 1% to about 40,50% of the market, 11.6% globally, 16.8% in low-income and 9.8% in high-income countries. The total lost revenue is about $40.5 billion a year. If this illicit trade were eliminated governments would gain at least $31.3 billion a year, and from 2030 onwards more than 164 000 premature deaths a year would be avoided, the vast majority in middle- and low-income countries. Conclusions The burden of deaths and lost revenue caused by the illicit cigarette trade falls disproportionately on low- and middle-income countries. Eliminating this trade would avoid millions of premature deaths, and recover billions of dollars for governments. [source] Preference and performance of the hyperparasitoid Syrphophagus aphidivorus (Hymenoptera: Encyrtidae): fitness consequences of selecting hosts in live aphids or aphid mummiesECOLOGICAL ENTOMOLOGY, Issue 6 2004R. Buitenhuis Abstract., 1.,Theoretical models predict that ovipositional decisions of parasitoid females should lead to the selection of the most profitable host for parasitoid development. Most parasitoid species have evolved specific adaptations to exploit a single host stage. However, females of the aphid hyperparasitoid Syrphophagous aphidivorus (Mayr) (Hymenoptera: Encyrtidae) display a unique and atypical oviposition behaviour by attacking either primary parasitoid larvae in live aphids, or parasitoid pupae in dead, mummified aphids. 2.,In the laboratory, the correlation between host suitability and host preference of S. aphidivorus on the host Aphidius nigripes Ashmead parasitising the aphid Macrosiphum euphorbiae (Thomas) was investigated. 3.,The relative suitability of the two host stages was determined by measuring hyperparasitoid fitness parameters (survival, development time, fecundity, sex ratio, and adult size of progeny), and calculating the intrinsic rate of population increase (rm). Host preference by S. aphidivorus females and the influence of aphid defence behaviour on host selection was also examined. 4.,Hyperparasitoid offspring performance was highest when developing from hosts in aphid mummies and females consistently preferred this host to hosts in parasitised aphids. Although aphid defensive behaviour may influence host selection, it was not a determining factor. Ecological and evolutionary processes that might have led to dual oviposition behaviour in S. aphidivorus are discussed. [source] The Impact of the Demand for Clinical Productivity on Student Teaching in Academic Emergency DepartmentsACADEMIC EMERGENCY MEDICINE, Issue 12 2004Todd J. Berger MD Objective: Because many emergency medicine (EM) attending physicians believe the time demands of clinical productivity limit their ability to effectively teach medical students in the emergency department (ED), the purpose of this study was to determine if there is an inverse relationship between clinical productivity and teaching evaluations. Methods: The authors conducted a prospective, observational, double-blind study. They asked senior medical students enrolled in their EM clerkship to evaluate each EM attending physician who precepted them at three academic EDs. After each shift, students anonymously evaluated 10 characteristics of clinical teaching by their supervising attending physician. Each attending physician's clinical productivity was measured by calculating their total relative value units per hour (RVUs/hr) during the nine-month study interval. The authors compared the total RVUs/hr for each attending physician to the medians of their teaching evaluation scores at each ED using a Spearman rank correlation test. Results: Seventy of 92 students returned surveys, evaluating 580 shifts taught by 53 EM attending physicians. Each attending physician received an average of 11 evaluations (median score, 5 of 6) and generated a mean of 5.68 RVUs/hr during the study period. The correlation between evaluation median scores and RVUs/hr was ,0.08 (p = 0.44). Conclusions: The authors found no statistically significant relationship between clinical productivity and teaching evaluations. While many EM attending physicians perceive patient care responsibilities to be too time consuming to allow them to be good teachers, the authors found that a subset of our more productive attending physicians are also highly rated teachers. Determining what characteristics distinguish faculty who are both clinically productive and highly rated teachers should help drive objectives for faculty development programs. [source] Stuart London's standard of living: re-examining the Settlement of Tithes of 1638 for rents, income, and povertyECONOMIC HISTORY REVIEW, Issue 3 2010WILLIAM C. BAER The Settlement of Tithes of 1638 can be tested for biases in its London rents. Even so, it proves to be a relatively good source for seventeenth-century London, and for calculating associated median and mean rents, as well as a Gini coefficient of inequality for the distribution of resources. Through other evidence in the Settlement, rent/income ratios for London can be approximated, and from them estimates made of London's median income. Median rents and income also allow estimates of the percentage of Londoners in poverty. Though the last is inevitably disputable, the estimate holds up well to testing by other evidence. [source] An Extended Analytical Approach to Credit Risk ManagementECONOMIC NOTES, Issue 2 2002Alexandre Kurth Among the ,reduced form models' for measuring the credit risk of a bank's portfolio is CreditRisk+, which provides a closed,form solution for calculating the portfolio loss distribution based on an actuarial approach. The limitations of this model are well known, but they are often misinterpreted as being deeply embedded within the model. Dismantling the mathematical components of the model allows one to modify and extend it in several ways while remaining within an analytical approach. One of the most unattractive features is the orthogonality of the background factors or sectors as it hinders any resemblance to real,world macroeconomic indexes or industrial sectors and geographical areas. Among other extensions, which we mention briefly, we present in more detail how the original model can be amended to consider correlations among default risk sectors and among severity risk segments. These extensions are applied to real,life data, based on mortality rate data produced by the Italian Central Bank. (J.E.L.: C00, C51). [source] | |||||||||||||||||||||||||||||||||||||