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Utility
Kinds of Utility Terms modified by Utility Selected AbstractsABSOLUTE FITNESS, RELATIVE FITNESS, AND UTILITYEVOLUTION, Issue 12 2007H. Allen Orr It is well known that (1) natural selection typically favors an allele with both a large mean fitness and a small variance in fitness; and (2) investors typically prefer a portfolio with both a large mean return and a small variance in returns. In the case of investors, this mean,variance trade-off reflects risk aversion; in the case of evolution, the mathematics is straightforward but the result is harder to intuit. In particular, it is harder to understand where, in the mathematics of natural selection, risk aversion arises. Here I present a result that suggests a simple answer to this question. Although my answer is essentially identical to one offered previously, my path to it differs somewhat from previous approaches. Some may find this new approach easier to intuit. [source] CHALLENGING CERTAINTY: THE UTILITY AND HISTORY OF COUNTERFACTUALISMHISTORY AND THEORY, Issue 1 2010SIMON T. KAYE ABSTRACT Counterfactualism is a useful process for historians as a thought-experiment because it offers grounds to challenge an unfortunate contemporary historical mindset of assumed, deterministic certainty. This article suggests that the methodological value of counterfactualism may be understood in terms of the three categories of common ahistorical errors that it may help to prevent: the assumptions of indispensability, causality, and inevitability. To support this claim, I survey a series of key counterfactual works and reflections on counterfactualism, arguing that the practice of counterfactualism evolved as both cause and product of an evolving popular assumption of the plasticity of history and the importance of human agency within it. For these reasons, counterfactualism is of particular importance both historically and politically. I conclude that it is time for a methodological re-assessment of the uses of such thought-experiments in history, particularly in light of counterfactualism's developmental relatedness to cultural, technological, and analytical modernity. [source] A MARKET UTILITY-BASED MODEL FOR CAPACITY SCHEDULING IN MASS SERVICESPRODUCTION AND OPERATIONS MANAGEMENT, Issue 2 2003JOHN C. GOODALE Only a small set of employee scheduling articles have considered an objective of profit or contribution maximization, as opposed to the traditional objective of cost (including opportunity costs) minimization. In this article, we present one such formulation that is a market utility-based model for planning and scheduling in mass services (MUMS). MUMS is a holistic approach to market-based service capacity scheduling. The MUMS framework provides the structure for modeling the consequences of aligning competitive priorities and service attributes with an element of the firm's service infrastructure. We developed a new linear programming formulation for the shift-scheduling problem that uses market share information generated by customer preferences for service attributes. The shift-scheduling formulation within the framework of MUMS provides a business-level model that predicts the economic impact of the employee schedule. We illustrated the shift-scheduling model with empirical data, and then compared its results with models using service standard and productivity standard approaches. The result of the empirical analysis provides further justification for the development of the market-based approach. Last, we discuss implications of this methodology for future research. [source] INFLATION AND THE PUBLIC DEFICIT WHEN THE UTILITY OF MONEY IS INSATIABLE,THE JAPANESE ECONOMIC REVIEW, Issue 2 2007ALEJANDRO RODRÍGUEZ-ARANA When the marginal utility of money is positive even at very high levels of the asset (Yoshiyasu Ono's, 1994, assumption), the relationship between inflation and the public deficit at full employment may result in a unique perverse equilibrium where higher deficits reduce inflation. If there are two equilibria, the low inflation equilibrium is one where the perverse effect between inflation and the public deficit prevails; while in the high inflation equilibrium higher public deficits increase inflation. These results contrast sharply with traditional results found in the literature. [source] THE PERFORMANCE OF AN ELECTRICITY UTILITY: THE CASE OF THE STATE ELECTRICITY COMMISSION OF VICTORIA, 1925,93AUSTRALIAN ECONOMIC HISTORY REVIEW, Issue 1 2006Malcolm Abbott Australia; electricity utility; privatisation; public enterprise; Victoria One of the most important microeconomic policy reforms of the 1990s was the restructuring of the Australian electricity supply industry. This process was encouraged by the perception that the state-owned electricity authorities performed poorly in the 1970s and 1980s. This article observes the long-term performance of the State Electricity Commission of Victoria over the course of most of its life. In particular the growth in demand for electricity in Victoria, the productivity growth of the State Electricity Commission of Victoria, as well as electricity prices, profits and debt levels are presented over the longer term. [source] A Shape Grammar for Developing Glyph-based VisualizationsCOMPUTER GRAPHICS FORUM, Issue 8 2009P. Karnick I.3.2 [Computer Graphics]: Graphics Systems; I.3.4 [Computer Graphics]: Graphics Utilities Abstract In this paper we address the question of how to quickly model glyph-based Geographic Information System visualizations. Our solution is based on using shape grammars to set up the different aspects of a visualization, including the geometric content of the visualization, methods for resolving layout conflicts and interaction methods. Our approach significantly increases modelling efficiency over similarly flexible systems currently in use. [source] SVG Linearization and AccessibilityCOMPUTER GRAPHICS FORUM, Issue 4 2002Ivan Herman Abstract The usage of SVG (Scaleable Vector Graphics) creates new possibilities as well as new challenges for theaccessibility of Web sites. This paper presents a metadata vocabulary to describe the information content ofan SVG file geared towards accessibility. When used with a suitable tool, this metadata description can helpin generating a textual ("linear") version of the content, which can be used for users with disabilities or withnon-visual devices. Although this paper concentrates on SVG, i.e. on graphics on the Web, the metadata approach and vocabularypresented below can be applied in relation to other technologies, too. Indeed, accessibility issues have a muchwider significance, and have an effect on areas like CAD, cartography, or information visualization. Hence, theexperiences of the work presented below may also be useful for practitioners in other areas. ACM CSS: I.3.4 Graphics Utilities,Graphics Packages, I.3.6 Methodology and Techniques,Graphics datastructures and data types, Standards, K.4.2 Social Issues,Assistive technologies for persons with disabilities [source] Gender and Ethnic Diversity Among UK Corporate BoardsCORPORATE GOVERNANCE, Issue 2 2007Stephen Brammer This paper investigates the ethnic and gender diversity of the corporate board of UK companies, placing particular emphasis on links to board size and industry characteristics. We employ a novel dataset that covers a large sample of UK PLCs and describes a director's gender, ethnicity and position held. We find both ethnic and gender diversity to be very limited, and that diversity is somewhat less pronounced among executive positions. We find significant cross-sector variation in gender diversity, with an above average prevalence of women in Retail, Utilities, Media and Banking, while such variation in ethnic diversity is considerably less pronounced. Our evidence suggests that a close proximity to final consumers plays a more significant role in shaping board diversity than does the female presence among the industry's workforce. We argue that this shows that board diversity is influenced by a firm's external business environment and particularly an imperative to reflect corresponding diversity among its customers. [source] Towards a Semiology of the Periodic Review of UK Regulated UtilitiesFINANCIAL ACCOUNTABILITY & MANAGEMENT, Issue 3 2001Stuart Cooper This note explores the regulatory process of UK privatised utilities through the periodic review of prices. It provides a brief history of the privatisation programme in the UK and the theoretical arguments for the price-cap regulation that has been used. It argues that regulatory process appears to involve a covert dialogue and exchange of information between the regulator and regulated and also a second separate review process that consists of an overt dialogue. Using a semiotic analysis the authors suggest that the unfolding of each of these overt reviews follows a very similar pattern that is constantly being re-enacted. It is concluded that further research is required into the relative importance of the two separate review processes in the setting of the price-cap. [source] Higher Cost, Lower Validity and Higher Utility: Comparing the Utilities of Two Tests that Differ in Validity, Costs and SelectivityINTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 2 2000George C. Thornton Traditional approaches to comparing the utility of two tests have not systematically considered the effects of different levels of selectivity that are feasible and appropriate in various selection situations. For example, employers who hope to avoid adverse impact often find they can be more selective with some tests than with others. We conducted two studies to compare the utilities of two tests that differ in costs, validity, and feasible levels of selectivity which can be employed. First, an analytical solution was conducted starting with a standard formula for utility. This analysis showed that for both fixed and variable hiring costs, a higher-cost, lower-validity procedure can have higher utility than a lower-cost, higher-validity procedure when the selection ratios permissible using the two procedures are sufficiently (yet realistically) different. Second, using a computer simulation method, several combinations of the critical variables were varied systematically to detect the limits of this effect in a finite set of specific selection situations. The results showed that the existence of more severe levels of adverse impact greatly reduced the utility of a written test with relatively high validity and low cost in comparison with an assessment center with lower validity and higher cost. Both studies showed that the consideration of selectivity can yield surprising conclusions about the comparative utility of two tests. Even if one test has lower validity and higher cost than a second test, the first may yield higher utility if it allows the organization to exercise stricter levels of selectivity. [source] Policy Transfer in European Union Governance: Regulating the Utilities , By S. Bulmer, D. Dolowitz, P. Humphreys and S. PadgettJCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 3 2007IAN BARTLE No abstract is available for this article. [source] Political and Regulatory Risk in Water Utilities: Beta Sensitivity in the United KingdomJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 7-8 2001Roger Buckland UK utilities are generally regulated by the periodic setting of a price cap (the RPI-X mechanism). To establish these caps, regulators must determine what returns are appropriate on the capital employed by utilities. This paper addresses the issue of the level of risk inherent in investment in the equity of regulated water utilities in the UK. It uses the techniques of the Kalman Filter to estimate daily betas for the major utilities in the period from privatisation to mid-1999. The paper demonstrates that water utilities' risk is time-variant. It demonstrates, also, that there have been significant political and regulatory influences in the systematic risk faced by water utility shareholders. It finds beta to display little evidence of cyclical variation across the regulatory review cycle. The paper also confirms that significant excess returns have been generated over the history of the privatised water sector and suggests that over-estimation of systematic risk faced by investors in the sector may imply further excess returns in the next regulatory review period. [source] Estimating the Relative Efficiency of Brazilian Publicly and Privately Owned Water Utilities: A Stochastic Cost Frontier Approach,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2007Geraldo Da Silva e Souza R15; R38 Abstract:, This paper assesses cost efficiencies of Brazilian public and private companies of water supply. To measure the efficiency, we used a stochastic frontier model derived from the translog family , a specification similar to a Cobb-Douglas including a quadratic term in log output. The model parameters are estimated by maximum likelihood using Brazilian data for the year 2002. Statistical inference leads to the conclusion that there is no evidence that private firms and public firms are significantly different in terms of efficiency measurements. [source] Utilities of the P -value Distribution Associated with Effect Size in Clinical Trials,BIOMETRICAL JOURNAL, Issue 6 2003H.M. James Hung Abstract The P -value, which is widely used for assessing statistical evidence in randomized comparative clinical trials, is a function of the observed effect size of the experimental treatment relative to the control treatment. The relationship of the P -value with the observed effect size at study completion and the effect size anticipated at the design stage has potential usefulness in providing guidance for planning and interpretation of a clinical trial. The post-trial power associated with a statistically significant P -value from a completed study is also a random variable and its use may assist in planning a follow-up trial to confirm the statistically significant findings in an initial study. A measure of robustness is explored to quantify the degree of sensitivity of the observed P -value to potential bias that may be contained in the observed effect size. [source] A public utilities board's executive limitations policyBOARD LEADERSHIP: POLICY GOVERNANCE IN ACTION, Issue 53 2001Article first published online: 14 MAR 200 An ends policy of Colorado Springs Utilities (CSU) was reviewed in Issue 51 of Board Leadership (Sept.-Oct. 2000). At that time, John Carver promised to examine one more policy from this public utility board. So here is CSU's policy regarding water rights. (The company is engaged in providing other utility services, but this policy relates only to the water portion of its job). [source] Two schedules of second-line irinotecan for metastatic colon carcinomaCANCER, Issue 11 2004Economic evaluation of a randomized trial Abstract BACKGROUND In a recently reported, randomized trial, it was found that a regimen of irinotecan once every 3 weeks for patients with advanced colorectal carcinoma was associated with a lower incidence of severe diarrhea compared with weekly treatment, and both regimens had similar efficacy. METHODS Resource utilization was captured prospectively for all 291 patients who were included in the trial. Utilities were estimated by transformation of the global quality-of-life (QOL) item on the Eastern Organization for Research and Treatment of Cancer QLQ-C30 instrument. RESULTS Patients in the every-3-week arm incurred an average incremental cost of $1362, because they received higher average weekly doses and because the every-3-week regimen resulted in less toxicity, allowing delivery of 97% of the planned doses compared with delivery of only 75% of the planned doses in the weekly arm. This lower toxicity also resulted in offsetting savings from decreased hospitalization and less requirement for supportive medications. Non-chemotherapy-related treatment administration costs also were lower, because the every-3-week regimen could be delivered with half the number of infusions. Utility declined less in the every-3-week arm, resulting in a saving of 6.3 quality-adjusted days. The base-case cost:utility ratio was $78,627 per quality-adjusted life year for patients on the every-3-week schedule. However, that ratio was very sensitive to the cost of irinotecan. CONCLUSIONS The schedule of irinotecan once every 3 weeks schedule was more costly but achieved lower toxicity, resulting in modestly improved utility. The cost-per-utility ratio was comparable to other commonly accepted contemporary treatments. Cancer 2004. © 2004 American Cancer Society. [source] Copper-Promoted/Catalyzed C,N and C,O Bond Cross-Coupling with Vinylboronic Acid and Its Utilities.CHEMINFORM, Issue 40 2003Patrick Y. S. Lam Abstract For Abstract see ChemInform Abstract in Full Text. [source] Growth hormone (GH) replacement in hypopituitary adults with GH deficiency evaluated by a utility-weighted quality of life index: a precursor to cost,utility analysisCLINICAL ENDOCRINOLOGY, Issue 1 2008Maria Ko, towska-Häggström Summary Objectives To examine quality of life (QoL) measured by a utility-weighted index in GH-deficient adults on GH replacement and analyse the impact of demographic and clinical characteristics on changes in utilities during treatment. Design Utilities for items in the QoL-Assessment of Growth Hormone Deficiency in Adults (QoL-AGHDAutility) were estimated based on data obtained from the general population in England and Wales (E&W). These estimates were used to calculate QoL changes in GH-treated patients and compare these with normative population values. Patients A total of 894 KIMS patients (53% women) from E&W were followed for 1 to 6 years. Measurements QoL-AGHDAutility at baseline and at the last reported visit, total QoL-AGHDAutility gain and QoL-AGHDAutility gain per year of follow-up. Results QoL-AGHDAutility in patients before GH treatment differed from the expected population values [0·67 (SD 0·174) vs. 0·85 (SD 0·038), P < 0·0001], constituting a mean deficit of ,0·19 (SD 0·168). There was a difference in the mean QoL-AGHDAutility deficit for men [,0·16 (SD 0·170)] and women [,0·21 (SD 0·162)] (P < 0·001). The main improvement occurred during the first year of treatment [reduction of a deficit to ,0·07 (SD 0·163) (P < 0·001) in the total cohort]; however, patients' utilities remained lower than those recorded for the general population during subsequent follow-up (P < 0·001). Despite an observed impact of age, primary aetiology, disease onset and comorbidities on QoL-AGHDAutility, all patients showed a similar beneficial response to treatment. Conclusions QoL-AGHDAutility efficiently monitors treatment effects in patients with GHD. The study confirmed the QoL-AGHDAutility deficit before treatment and a similar QoL-AGHDAutility gain observed after commencement of GH replacement in all patients. [source] Effect of Normal Saline Infusion on the Diagnostic Utility of Base Deficit in Identifying Major Injury in Trauma PatientsACADEMIC EMERGENCY MEDICINE, Issue 12 2006Richard Sinert DO Abstract Background Base deficit (BD) is a reliable marker of metabolic acidosis and is useful in gauging hemorrhage after trauma. Resuscitation with chloride-rich solutions such as normal saline (NS) can cause a dilutional acidosis, possibly confounding the interpretation of BD. Objectives To test the diagnostic utility of BD in distinguishing minor from major injury after administration of NS. Methods This was a prospective observational study at a Level 1 trauma center. The authors enrolled patients with significant mechanism of injury and measured BD at triage (BD-0) and at four hours after triage (BD-4). Major injury was defined by any of the following: injury severity score of ,15, drop in hematocrit of ,10 points, or the patient requiring a blood transfusion. Patients were divided into a low-volume (NS < 2L) and a high-volume (NS , 2L) group. Data were reported as mean (±SD). Student's t- and Wilcoxon tests were used to compare data. Receiver operating characteristic (ROC) curves tested the utility of BD-4 in differentiating minor from major injury in the study groups. Results Four hundred eighty-nine trauma patients (mean age, 36 [± 18] yr) were enrolled; 82% were male, and 34% had penetrating injury. Major-(20%) compared with minor-(80%) injury patients were significantly (p = 0.0001) more acidotic (BD-0 mean difference: ,3.3 mmol/L; 95% confidence interval [CI] =,2.5 to ,4.2). The high-volume group (n = 174) received 3,342 (±1,821) mL, and the low-volume group (n = 315) received 621 (±509) mL of NS. Areas under the ROC curves for the high-volume (0.63; 95% CI = 0.52 to 0.74) and low-volume (0.73; 95% CI = 0.60 to 0.86) groups were not significantly different from each other. Conclusions Base deficit was able to distinguish minor from major injury after four hours of resuscitation, irrespective of the volume of NS infused. [source] Validation and Clinical Utility of a Simple In-Home Testing Tool for Sleep-Disordered Breathing and Arrhythmias in Heart Failure: Results of the Sleep Events, Arrhythmias, and Respiratory Analysis in Congestive Heart Failure (SEARCH) StudyCONGESTIVE HEART FAILURE, Issue 5 2006William T. Abraham MD Fifty patients with New York Heart Association class III systolic heart failure were enrolled in this prospective multicenter study that compared the diagnostic accuracy of a home-based cardiorespiratory testing system with standard attended polysomnography. Patients underwent at least 2 nights of evaluation and were scored by blinded observers. At diagnostic cutoff points of ,5, ,10, and ,15 events per hour for respiratory disturbance severity, polysomnography demonstrated a sleep-disordered breathing prevalence of 69%, 59%, and 49%, respectively. Compared with polysomnography, the cardiorespiratory testing system demonstrated predictive accuracies of 73%, 73%, and 75%, which improved to 87%, 87%, and 83%, respectively, when analysis of covariance suggested reanalysis omitting one site's data. The system accurately identified both suspected and unsuspected arrhythmias. The device was judged by 80% of patients to be easy or very easy to use, and 74% of patients expressed a preference for the in-home system. Therefore, this system represents a reasonable home testing device in these patients. [source] Utility of flow cytometry immunophenotyping in multiple myeloma and other clonal plasma cell-related disorders,CYTOMETRY, Issue 4 2010Bruno Paiva Abstract In recent years, multiparameter flow cytometry (MFC) immunophenotyping has become mandatory in the clinical management of hematological malignancies, both for diagnostic and monitoring purposes. Multiple myeloma (MM) and other clonal plasma cell-related (PC) disorders should be no exception to this paradigm, but incorporation of immunophenotypic studies in the management of patients with PC disorders is still far from being routinely established in many diagnostic flow cytometry laboratories. For clonal PC disorders, MFC is of clear and established clinical relevance in: (1) the differential diagnosis between MM and other PC-related disorders; (2) the identification of high-risk MGUS and smoldering MM; (3) minimal residual disease investigation after therapy; additionally it may also be useful for (4) the definition of prognosis-associated antigenic profiles; and (5) the identification of new therapeutic targets. In this article, we review the clinical value of MFC in the study of PC disorders, with specific emphasis in those areas where consensus exists on the need to incorporate MFC into routine evaluation of MM and other clonal PC-related disorders. © 2010 Clinical Cytometry Society [source] Utility of CD26 in flow cytometric immunophenotyping of T-cell lymphomas in tissue and body fluid specimens,CYTOMETRY, Issue 6 2008Diane M. Pierson Abstract Background CD26 is expressed by most CD4+ T cells in normal peripheral blood specimens. Neoplastic T cells are frequently CD26, in mycosis fungoides/Sezary syndrome involving the peripheral blood. However, CD26 expression by reactive and neoplastic T cells in solid tissues and body fluids has not been fully characterized by flow cytometry (FC). Methods Solid tissue and body fluid specimens were assayed for CD26 expression using four-color FC immunophenotyping, by qualitative assessment of population clusters, and by quantitation with comparison with isotype controls. Benign T cells were studied in reactive tissues and in the background of other malignancies. Results Many T-cell lymphomas were dim or negative for CD26, whereas a few were brightly positive. In the majority of T-cell lymphomas, CD26 expression could potentially help identify aberrant population clusters. T cells in reactive tissue specimens and tumor-infiltrating T cells were commonly dim to negative for CD26. Conclusions Both T-cell lymphomas and reactive T cells in tissue and body fluid specimens often show low levels of CD26 expression. Therefore, quantitative methods may not reliably distinguish benign from neoplastic T cells in these specimens. However, CD26, in combination with other T-cell markers, can be helpful for identifying aberrant population clusters in T-cell lymphomas. © 2008 Clinical Cytometry Society [source] THE MOLECULAR FUTURE IN CYTOLOGYCYTOPATHOLOGY, Issue 2006M. Salto-Tellez Molecular diagnosis is the application of molecular biology techniques and knowledge of the molecular mechanisms of disease to diagnosis, prognostication and treatment of diseases. Molecular Diagnosis is, arguably, the fastest growing area of diagnostic medicine. The US market for molecular testing generated $1.3 billion in 2000, which was predicted to increase to about $4.2 billion by 2007.1 We proposed the term Diagnostic Molecular Cytopathology to define the application of molecular diagnosis to cytopathology2. Diagnostic Molecular Cytopathology is essential for the following reasons: (i) Molecular testing is sometimes indispensable to establish an unequivocal diagnosis on cell preparations; (ii) Molecular testing provides extra information on the prognosis or therapy of diseases diagnosed by conventional cytology; (iii) Molecular testing provides genetic information on the inherited nature of diseases that can be directly investigated in cytology samples, by either exfoliation or by fine needle aspiration; (iv) Sometimes the cytopathology sample is the most convenient (or the only available) source of material for molecular testing; (v). Direct molecular interrogation of cells allows for a diagnostic correlation that would otherwise not be possible. Parallel to this direct diagnostic implication, cytopathology is increasing important in the validation of biomarkers for specific diseases, and in therefore of significant importance in the overall translational research strategies. We illustrate its application in some of the main areas of oncology molecular testing, such as molecular fingerprinting of neoplasms,3 lymphoreticular diseases,2 sarcomas4 and lung cancer,5 as well as translational research using diagnostic cytopathology techniques. The next years will see the consolidation of Diagnostic Molecular Cytopathology, a process that will lead to a change of many paradigms. In general, diagnostic pathology departments will have to reorganize molecular testing to pursue a cost-efficient operation. Sample preparation will have to take into account optimal preservation of nuclear acids. The training of technical staff and the level of laboratory quality control and quality assurance would have to follow strict clinical (not research) laboratory parameters. And, most importantly, those pathologists undertaking molecular diagnosis as a discipline would have to develop their professional expertise within the same framework of fellowships and professional credentials that is offered in other sub-specialties. The price to pay if this effort is not undertaken is too important for the future of diagnostic pathology in general. The increasing characterization of molecular biomarkers with diagnostic, prognostic or therapeutic value is making the analysis of tissue and cell samples prior to treatment a more complex exercise. If cytopathologists and histopathologists allow others to take charge of molecular diagnosis, our overall contribution to the diagnostic process will be diminished. We may not become less important, but we may become less relevant. However, those within the discipline of diagnostic pathology who can combine the clinical background of diseases with the morphological, immunocytochemical and molecular diagnostic interpretation will represent bona fide diagnostic specialists. Such ,molecular cytopathologists' would place themselves at the centre of clinical decision-making. Reference:, 1. Liz Fletcher. Roche leads molecular diagnostics charge. Nature Biotechnol 20, 6,7; 2002 2. Salto-Tellez M and Koay ESC. Molecular Diagnostic Cytopathology - Definitions, Scope and Clinical Utility. Cytopathology 2004; 15:252,255 3. Salto-Tellez M, Zhang D, Chiu LL, Wang SC, Nilsson B, and Koay ESC. Immunocytochemistry Versus Molecular Fingerprinting of Metastases. Cytopathology, 2003 Aug; 14(4):186,90. 4. Chiu LL, Koay SCE, Chan NL and Salto-Tellez M. Molecular Cytopathology: Sequencing of the EWS-WT1 Gene Fusion Transcript in the Peritoneal Effusion of a Patient with Desmoplastic Small Round Cell Tumour. Diagnostic Cytopathology, 2003 Dec; 29(6): 341,3. 5. TM Chin, D Anuar, R Soo, M Salto-Tellez, WQ Li, B Ahmad, SC Lee, BC Goh, K Kawakami, A Segal, B Iacopetta, R Soong. Sensitive and Cost-Effective deptection of epidermal growth factor Receptor Mutations in Small Biopsies by denaturing High Performance Liquid Chromatography. (In press). [source] Distribution of Aggregate Utility Using Stochastic Elements of Additive Multiattribute Utility ModelsDECISION SCIENCES, Issue 2 2000Herbert Moskowitz ABSTRACT Conventionally, elements of a multiattribute utility model characterizing a decision maker's preferences, such as attribute weights and attribute utilities, are treated as deterministic, which may be unrealistic because assessment of such elements can be imprecise and erroneous, or differ among a group of individuals. Moreover, attempting to make precise assessments can be time consuming and cognitively demanding. We propose to treat such elements as stochastic variables to account for inconsistency and imprecision in such assessments. Under these assumptions, we develop procedures for computing the probability distribution of aggregate utility for an additive multiattribute utility function (MAUF), based on the Edgeworth expansion. When the distributions of aggregate utility for all alternatives in a decision problem are known, stochastic dominance can then be invoked to filter inferior alternatives. We show that, under certain mild conditions, the aggregate utility distribution approaches normality as the number of attributes increases. Thus, only a few terms from the Edgeworth expansion with a standard normal density as the base function will be sufficient for approximating an aggregate utility distribution in practice. Moreover, the more symmetric the attribute utility distributions, the fewer the attributes to achieve normality. The Edgeworth expansion thus can provide a basis for a computationally viable approach for representing an aggregate utility distribution with imprecisely specified attribute weights and utilities assessments (or differing weights and utilities across individuals). Practical guidelines for using the Edgeworth approximation are given. The proposed methodology is illustrated using a vendor selection problem. [source] Utility of Intralesional Sclerotherapy with 3% Sodium Tetradecyl Sulphate in Cutaneous Vascular MalformationsDERMATOLOGIC SURGERY, Issue 3 2010MNAMS, SUJAY KHANDPUR MBBS BACKGROUND Vascular malformations have devastating cosmetic effects in addition to being associated with pain and bleeding. Sclerotherapy has been successfully used in treating complicated hemangiomas and vascular malformations. OBJECTIVES To assess the efficacy of sclerotherapy with 3% sodium tetradecyl sulphate (STS) in venous and lymphatic malformations. MATERIALS AND METHOD We performed sclerotherapy with 3% STS in 13 patients with venous malformations and microcystic lymphatic malformation, all low-flow malformations and with extent predominantly to the subcutis, confirmed using Doppler ultrasound. Lesions were located on the face, lower lip, flanks, buttocks, and extremities. Patients presented for cosmetic reasons, pain, or bleeding. Sclerotherapy was undertaken as an office procedure without any radiological guidance and therapy repeated every 3 weeks. Therapeutic efficacy was assessed subjectively clinically and photographically. RESULTS The lesions regressed by 90% to 100% in 11 cases after a mean of four injections, with no improvement in two cases (one each of venous malformation and lymphatic malformation). Complications included cutaneous blister formation, erosions, and crusting at injection site in seven cases and atrophic scarring in four patients. CONCLUSIONS Sclerotherapy with 3% STS is a simple, safe, and effective modality for venous malformations and can be undertaken as an office procedure in lesions limited to the subcutis. The authors have indicated no significant interest with commercial supporters. [source] Utility of Hair Clips for Scalp SurgeriesDERMATOLOGIC SURGERY, Issue 5 2006CHANDRASHEKAR LAXMISHA MD No abstract is available for this article. [source] Utility of a Bilayered Banner Transposition Flap in Reconstruction of the Lower Third of the PinnaDERMATOLOGIC SURGERY, Issue 7 2000Dania Tannir MD Background. Reconstruction of the entire ear lobule is challenging and complex. We present a case in which a banner transposition flap from the preauricular and mandibular area of the cheek resulted in an excellent cosmetic outcome. Objective. To demonstrate the utility of a bilayered banner transposition flap to reconstruct a full-thickness defect of the inferior one-third of the pinna. Methods., The technique employed in this reconstruction is described and previously reported techniques are reviewed. Results., A symmetrical earlobe with normal tissue consistency was created, as noted at 4 months postoperatively. Conclusion. Utilization of a banner transposition flap should be considered as an excellent method for reconstruction of full-thickness defects of the lower one-third of the ear. [source] Nuclear morphometry and texture analysis of B-cell non-Hodgkin lymphoma: Utility in subclassification on cytosmearsDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2010Shilpa Gupta M.D. Abstract Non-Hodgkin lymphoma (NHL) is a heterogeneous group of lymphoid neoplasms and accurate subclassification is an essential prerequisite for proper management of patients. This study was aimed at evaluating the utility of nuclear morphometry and textural features on cytology smears to classify the cases of NHL on aspiration cytology. Fine needle aspiration smears of 50 cases of B-cell NHL were included. Various morphometric and texture parameters were obtained by manually tracing the nuclei on digitized images in each case and discriminant analysis performed using various features taken individually as well as all together. The percentage of cells correctly classified to a particular NHL subtype using the discriminant functions so obtained was noted. Our results show that discriminant analysis done on size parameters could correctly classify a greater number of cells than on shape parameters (36.4% vs. 21.2%, respectively). Texture parameters based on single pixel values (first order texture) were inferior (42.8%) to those based on pair of pixels (58.7%) in subtyping of cells. Discriminant analysis based on color parameters was more effective (61.9%) as compared to rest of the morphometric and textural parameters. Using all the morphometric and textural parameters together, 83.3% of cells could be correctly classified to a particular NHL subtype. The present study, perhaps the first study of detailed morphometric analysis on cytosmears, shows that satisfactory classification of NHL on aspiration cytology is possible using nuclear morphometry and textural parameters considered together. These results are promising for further studies on this subject and development of automated cytodiagnosis. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc. [source] Utility of the thromboplastin-plasma cell-block technique for fine-needle aspiration and serous effusionsDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2009D.M.L.T., Manisha B. Kulkarni M.Sc. Abstract (I) To assess the feasibility of thromboplastin-plasma (TP) method for cell block, (II) to concentrate the minimal cellular material from effusions and needle-rinses by block preparation and improve visual details, (III) to compare conventional cytological smears with cell blocks for final assessment, and (IV) to assess utility of immunocytochemistry (ICC) for diagnostic accuracy. Seventy cell blocks were prepared by TP technique using surplus fluid from 38 serous effusions, and for 32 ultrasonography-guided fine-needle aspiration cytology (FNAC) material, rinses of syringes and needles were collected in normal saline after conventional cytological smears. Then, cell blocks were compared with conventional smears for adequacy, morphologic preservation, and ICC. Absolute concordance seen in 66 cases (94%) between the smears and cell blocks. Advantages with the blocks were cellular concentration in a limited field and better cellular preservation with architectural pattern. Quality of ICC was comparable to that of standard controls. Diagnostic discrepancy was seen in two cases where cell blocks were positive but smears were negative. Two cell blocks were nonrepresentative. Cell block serves as a useful adjunct to traditional cytological smears. TP method is simple, cost effective, and reproducible. It is easy when compared with agar-embedding technique. Ancillary techniques like ICC can be performed successfully. Diagn. Cytopathol. 2009. © 2008 Wiley-Liss, Inc. [source] Utility of cell blocks in the diagnosis of thyroid aspiratesDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2006Niria Sanchez M.D. Abstract Cell blocks (CBs) are often prepared with fine-needle aspirates (FNAs) from multiple organs as an adjunct to smears in the diagnosis of aspirated lesions. However, the literature contains few reports on their utility with regard to specific organ sites. At our institution, CBs are made routinely on FNAs when there is sufficient material remaining after smear preparation, with thyroid representing the largest volume. The aim of this study was to determine the utility of CBs in the diagnosis of thyroid lesions. From January 2002 to April 2004, 546 thyroid FNAs were performed. Eighty-two (15%) cases, from 60 females and 20 males (age range, 17,88 yr; mean, 50 yr), had CBs and formed the basis of this study. Seventy-four (90%) of the cases were performed by the radiologist or the clinician and 8 (10%) by the pathologist, all of which had an immediate assessment for adequacy. One to 7 passes were performed with an average of 3/case. The needles were immediately rinsed in Hanks' Balanced Salt Solution after smear preparation. CBs were made on bloody specimens/those with tissue fragments. Cell-block slides were reviewed for the presence of cellular elements and classified into three categories: (1) contributory, (2) noncontributory, or (3) provides additional information. Of the 82 cases, 23 (28%) were neoplastic, 51 (62%) were nonneoplastic, and 8 (10%) were nondiagnostic. Fifteen of the neoplastic cases had confirmatory biopsies, 9 of which were papillary carcinoma. The overall cellularity of the CBs was low, varying from 0 to 2 follicular groups in the noncontributory CBs and 3 to 6 follicular groups or papillary formations in the contributory CBs. CBs were contributory in 25 (31%) cases: 5 neoplastic (1 follicular neoplasm, 3 papillary carcinoma, and 1 suspicious for papillary carcinoma), 18 nonneoplastic, and 2 nondiagnostic. CBs were noncontributory in 56 (68%) cases: 18 neoplastic (4 papillary carcinomas, 1 suspicious for papillary carcinoma, 4 Hürthle cell neoplasms, and 9 follicular neoplasms), 33 nonneoplastic, and 5 nondiagnostic. One case was categorized as provided additional information because the CB showed material that was not present on the slides; however, it was still nondiagnostic. In summary, CBs did not help in the majority of cases. They were contributory in only 25 (31%) of the 82 cases, and of the 23 neoplastic cases, only 5 (22%) CBs were contributory. The contribution of the CBs in the diagnosis of thyroid lesions was minimal because of the low cellularity. On-site assessment of specimen adequacy often results in fewer passes, thus contributing to the low cellularity present in cell-block preparations. Ancillary studies may require additional passes. Diagn. Cytopathol. 2006; 34:89,92. © 2006 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||||||||