Comparative assessment of three common algorithms for estimating the variance of the area under the nonparametric receiver operating characteristic curve

The area under the receiver operating characteristic (ROC) curve is often used to summarize and compare the discriminatory accuracy of a diagnostic test or modality,and to evaluate the predictive power of statistical models for binary outcomes. Parametric maximum likelihood methods for Þtting of the ROC curve provide direct estimates of the area under the ROC curve and its variance. Nonparametric methods, on the other hand, provide estimates of the area under the ROC curve, but do not directly estimate its variance. Three algorithms for computing the variance for the area under the nonparametric ROC curve are commonly used, although ambiguity exists about their behavior under diverse study conditions. Using simulated data, we found similar asymptotic performance between these algorithms when the diagnostic test produces results on a continuous scale, but found notable differences in small samples, and when the diagnostic test yields results on a discrete diagnostic scale. Copyright 2002 by Stata Corporation.receiver operating characteristic (ROC )curve,trapezoidal rule, sensitivity,specificity,discriminatory accuracy,predictive power

From the help desk: Comparing areas under receiver operating characteristic curves from two or more probit or logit models

Occasionally, there is a need to compare the predictive accuracy of several fitted logit (logistic) or probit models by comparing the areas under the corresponding receiver operating characteristic (ROC) curves. Although Stata currently does not have a ready routine for comparing two or more ROC areas generated from these models, this article describes how these comparisons can be performed using Stata's roccomp command. Copyright 2002 by Stata Corporation.Receiving Operating Characteristic (ROC) curve

Parallel developmental genetic features underlie stickleback gill raker evolution.

BackgroundConvergent evolution, the repeated evolution of similar phenotypes in independent lineages, provides natural replicates to study mechanisms of evolution. Cases of convergent evolution might have the same underlying developmental and genetic bases, implying that some evolutionary trajectories might be predictable. In a classic example of convergent evolution, most freshwater populations of threespine stickleback fish have independently evolved a reduction of gill raker number to adapt to novel diets. Gill rakers are a segmentally reiterated set of dermal bones important for fish feeding. A previous large quantitative trait locus (QTL) mapping study using a marine × freshwater F2 cross identified QTL on chromosomes 4 and 20 with large effects on evolved gill raker reduction.ResultsBy examining skeletal morphology in adult and developing sticklebacks, we find heritable marine/freshwater differences in gill raker number and spacing that are specified early in development. Using the expression of the Ectodysplasin receptor (Edar) gene as a marker of raker primordia, we find that the differences are present before the budding of gill rakers occurs, suggesting an early change to a lateral inhibition process controlling raker primordia spacing. Through linkage mapping in F2 fish from crosses with three independently derived freshwater populations, we find in all three crosses QTL overlapping both previously identified QTL on chromosomes 4 and 20 that control raker number. These two QTL affect the early spacing of gill raker buds.ConclusionsCollectively, these data demonstrate that parallel developmental genetic features underlie the convergent evolution of gill raker reduction in freshwater sticklebacks, suggesting that even highly polygenic adaptive traits can have a predictable developmental genetic basis

Inclusi?n educativa de estudiantes con s?ndrome de Asperger en el colegio gimnasio campestre de Ibagu?, estudio de caso

123 p. Recurso Electr?nicoInclusi?n educativa de estudiantes con s?ndrome de Asperger en el Colegio Gimnasio Campestre de Ibagu?, es una investigaci?n que responde a un inter?s intr?nseco que pretende caracterizar los procesos de inclusi?n educativa desarrollados al interior del colegio y con la poblaci?n Asperger. Mediante el uso de la investigaci?n cualitativa y particularmente del estudio de caso de Nicol?s P?rez quien es un estudiante de grado 9? diagnosticado desde su infancia. Dentro de los instrumentos para la recolecci?n de la informaci?n seleccionados se encuentran la revisi?n de documentos como el proyecto educativo institucional (PEI) el manual de convivencia escolar del colegio, la observaci?n participante de las clases, el uso del diario de campo para el registro de comportamientos y hechos de particular inter?s ocurridos durante la cotidianidad escolar, adem?s de la entrevista semiestructurada a docentes, directivos docentes, padres de familia y rector con el fin de reconocer practicas inclusivas para con Nicol?s P?rez. Los hallazgos de la investigaci?n muestran que en el colegio Gimnasio Campestre se desarrollan procesos de inclusi?n de forma indirecta sin existir al respecto pol?ticas oficiales enmarcadas en el proyecto educativo institucional; se resalta finalmente que las intenciones del colegio para la atenci?n a los estudiantes necesidades educativas especiales permiten la aparici?n de espacios en los que todos los integrantes de la comunidad educativa reconocen la diferencia. Los docentes, personal administrativo e incluso la poblaci?n estudiantil requieren de mayor informaci?n y capacitaci?n para la socializar asertivamente con esta poblaci?n. Palabras Clave: Integraci?n educativa, inclusi?n educativa, necesidades educativas especiales, s?ndrome de Asperger.Educational inclusion of students with Asperger syndrome at Gimnasio Campestre in Ibagu?, it is an investigation that answers out an intrinsic interest that aims to characterize the processes of educational inclusion developed within the school and with the Asperger population. Throughout the use of qualitative research and particularly the study case of Nicol?s P?rez who is a 9th grade student diagnosed since childhood. Among the instruments for the collection of selected information are the revision of documents such as the institutional educational project (PEI), the school's coexistence manual, the participant observation of the classes, the use of the field diary for the registration of behaviors and facts of particular interest that occurred during the daily school life, in addition to the semistructured interview with teachers, teaching directors, parents and the principal in order to recognize inclusive practices for Nicol?s P?rez. The research findings show that at the Gimnasio Campestre school, inclusion processes are developed indirectly without any official policies within the institutional educational project; Finally, it is emphasized that the intentions of the school to attend to students special educational needs allow the appearance of spaces in which all members of the educational community recognize the difference. The teachers, administrative staff and even the student population require of more information and training to socialize assertively with this population. Keywords: Educational integration, educational inclusion, special educational needs, Asperger syndrome

Biopsia por punción, en los tumores del seno maxilar

Gracias a los adelantos actuales de los exámenes citológicos, en relación con la determinación de los procesos tumorales malignos, contamos en nuestra especialidad con un medio más para el diagnóstico de los tumores de los senos maxilares.Al examen clínico y radiológico podemos agregar hoy día el examen citológico, el cual tiene la enorme ventaja de ser de fácil ejecución, sin los inconvenientes que por el traumatismo se presenten cuando se practica la biopsia del tumor haciendo una trepanación de la pared anterior del seno maxilar, previa incisión de la mucosa bucal sobre el surco gingivolabial. En esta comunicación presentamos 4 casos clínicos de pacientes del Instituto de Radium, en los cuales como veremos en su historia clínica se comprobó la lesión neoplásica por medio de la radiografía y de biopsia practicadas según los antiguos procedimientos

Can we use biomarkers of coagulation to predict which patients with foot and ankle injury will develop vein thrombosis?

Background Our aim was to determine whether plasma levels of Tissue Factor (TF), Vascular Cell Adhesion Molecule 1 (VCAM-1), Interleukin 6 (IL-6) or D-dimer after foot and ankle injury could predict which patients would develop deep vein thrombosis (DVT). Methods Patients aged 18–60 years with acute foot and ankle injury had venous blood sample to measure TF, VCAM-1, IL-6 and D-dimer within 3 days of injury. Patients had bilateral lower limb venous ultrasound to assess for DVT on discharge from clinic. Results 21 of 77 patients were found to have DVT (27%). There was no statistically significant association between levels of TF, VCAM-1, IL-6 or D-dimer and subsequent development of DVT. Conclusion Tissue Factor (TF), Vascular Cell Adhesion Molecule-1 (VCAM-1), Interleukin-6 (IL-6) and D-dimer levels were not associated with development deep vein thrombosis in patients with acute foot and ankle injury

Propranolol for Treatment of Infantile Hemangioma: Efficacy and Effect on Pediatric Growth and Development

Purpose. Propranolol has been successful in treating problematic infantile hemangiomas (IH) but concerns regarding its effect on normal growth and development have been raised. This study examines physical growth, developmental milestones, and human growth hormone (hGH) levels in infants receiving propranolol for problematic IH. Method. Monthly heights and weights of children undergoing propranolol therapy for IH were prospectively collected and tabulated. Data analysis and comparison to World Health Organization (WHO) weight-for-age and weight-to-length z-scores was performed. Questionnaires regarding milestones, efficacy, and guardian satisfaction were performed, and a combination of both chart results and phone conducted surveys was tabulated. Serum from a small representative cohort of age-matched children with IH treated and not treated with propranolol was collected. Results. A total of 185 children receiving propranolol therapy between 2008 and 2013 for IH were assigned to this study. The children were divided into two cohorts based on the presence of comorbidities or risk factors that may affect growth and development (n = 142 no comorbidities, n = 43 with comorbidities). Neither cohort demonstrated deviation from normal weight in comparison to WHO normative data. There was a significant deviation for BMI-for-age and weight-for-age z-scores in our population, especially in patients on propranolol for more than 7 months. Based on data from participants, via either completed questionnaires or chart results, most children met their developmental milestones at or before target ages, regardless of the presence of comorbidities. Eighty percent of guardians noticed clinical improvement of the IH, with 91% either happy about or neutral to using the medication. hGH levels were higher in patients receiving propranolol therapy, but not significantly different. Conclusion. Propranolol therapy is effective and well tolerated in the treatment of infantile hemangiomas. This study suggests that propranolol does not impair growth and has no impact on normal pediatric development

Varied effects of algal symbionts on transcription factor NF-κB in a sea anemone and a coral: possible roles in symbiosis and thermotolerance

Many cnidarians, including the reef-building corals, undergo symbiotic mutualisms with photosynthetic dinoflagellate algae of the family Symbiodiniaceae. These partnerships are sensitive to temperature extremes, which cause symbiont loss and increased coral mortality. Previous studies have implicated host immunity and specifically immunity transcription factor NF-κB as having a role in the maintenance of the cnidarian-algal symbiosis. Here we have further investigated a possible role for NF-κB in establishment and loss of symbiosis in various strains of the anemone Exaiptasia (Aiptasia) and in the coral Pocillopora damicornis. Our results show that NF-κB expression is reduced in Aiptasia larvae and adults that host certain algae strains. Treatment of Aiptasia larvae with a known symbiosis-promoting cytokine, transforming growth factor β, also led to decreased NF-κB expression. We also show that aposymbiotic Aiptasia (with high NF-κB expression) have increased survival following infection with the pathogenic bacterium Serratia marcescens as compared to symbiotic Aiptasia (low NF-κB expression). Furthermore, a P. damicornis coral colony hosting Durusdinium spp. (formerly clade D) symbionts had higher basal NF-κB expression and decreased heat-induced bleaching as compared to two individuals hosting Cladocopium spp. (formerly clade C) symbionts. Lastly, genome-wide gene expression profiling and genomic promoter analysis identified putative NF-κB target genes that may be involved in thermal bleaching, symbiont maintenance, and/or immune protection in P. damicornis. Our results provide further support for the hypothesis that modulation of NF-κB and immunity plays a role in some, but perhaps not all, cnidarian-Symbiodiniaceae partnerships as well as in resistance to pathogens and bleaching.Accepted manuscrip