An evaluation of electrochemical concentration Cell (ECC) sonde measurements of atmospheric ozone

Using Dobson spectrophotometer measurements of total ozone as a comparison, an analysis of the electrochemical concentration cell (ECC) ozonesonde's measurement accuracy is presented. Days of conjunctive ECC-Dobson observations (from 1970 to 1976 at Wallops Flight Center) provide a set of 123 pairs of total ozone values. Sample set statistics are generated with means and standard deviations of total ozone values and differences being noted. An in-depth study of factors such as time assumptions used in calculating residual ozone, and other possible sources of errors are examined. A study of ECC ozone profiles is also presented with an evaluation of sonde measurement of seasonal trends, altitude or peak ozone concentration, and other important ozone parameters. Short-period changes in total ozone using Dobson data during the observational period are also described

Professional development through the use of technology

The purpose of this study was to introduce the Gloucester County Special Services School District educators to the concept of using technology for the purpose of professional development. A descriptive research method was used in the study that included a Technology Survey of the Compensatory Education Teachers. Surveys were distributed prior to and following the inservice component of the study. The technology survey instrument utilized was developed by the Intern and pretested by administrators and educators in the district. The frequency of responses were recorded and calculated into percentages for purposes of data analysis. After experiencing exposure to the Internet through a Technology Inservice program, an overall improvement in attitude and comfort level regarding technology and accessing the Internet was reported by respondents. Individuals self-rating themselves within the ranges of very comfortable to somewhat comfortable increased substantially and the percentage of individuals rating themselves as uncomfortable prior to the inservice decreased. Following the inservice, 86% of the individuals surveyed reported utilizing the Internet as a resource for lesson planning and locating educational materials. This figure is significant in that it represents an increase of 64% as reported by respondents. The study supports establishing a relationship between professional development and technology and identifies the important role inservicing plays in this process

Linear quantile mixed models

Dependent data arise in many studies. For example, children with the same parents or living in neighbouring geographic areas tend to be more alike in many characteristics than individuals chosen at random from the population at large; observations taken repeatedly on the same individual are likely to be more similar than observations from different individuals. Frequently adopted sampling designs, such as cluster, multilevel, spatial, and repeated measures (or longitudinal or panel), may induce this dependence, which the analysis of the data needs to take into due account. In a previous publication (Geraci and Bottai, Biostatistics 2007), we proposed a conditional quantile regression model for continuous responses where a random intercept was included along with fixed-coefficient predictors to account for between-subjects dependence in the context of longitudinal data analysis. Conditional on the random intercept, the response was assumed to follow an asymmetric Laplace distribution. The approach hinged upon the link existing between the minimization of weighted least absolute deviations, typically used in quantile regression, and the maximization of Laplace likelihood. As a follow up to that study, here we consider an extension of those models to more complex dependence structures in the data, which are modelled by including multiple random effects in the linear conditional quantile functions. Differently from the Gibbs sampling expectation-maximization approach proposed previously, the estimation of the fixed regression coefficients and of the random effects covariance matrix is based on a combination of Gaussian quadrature approximations and optimization algorithms. The former include Gauss-Hermite and Gauss-Laguerre quadratures for, respectively, normal and double exponential (i.e., symmetric Laplace) random effects; the latter include a gradient search algorithm and general purpose optimizers. As a result, some of the computational burden associated with large Gibbs sample sizes is avoided. We also discuss briefly an estimation approach based on generalized Clarke derivatives. Finally, a simulation study is presented and some preliminary results are shown

Improved constraints on non-Newtonian forces at 10 microns

Several recent theories suggest that light moduli or particles in "large" extra dimensions could mediate macroscopic forces exceeding gravitational strength at length scales below a millimeter. Such new forces can be parameterized as a Yukawa-type correction to the Newtonian potential of strength $\alpha$ relative to gravity and range $\lambda$. To extend the search for such new physics we have improved our apparatus utilizing cryogenic micro-cantilevers capable of measuring attonewton forces, which now includes a switchable magnetic force for calibration. Our most recent experimental constraints on Yukawa-type deviations from Newtonian gravity are more than three times as stringent as our previously published results, and represent the best bound in the range of 5 - 15 microns, with a 95 percent confidence exclusion of forces with $|\alpha| > 14,000$ at $\lambda$ = 10 microns.Comment: 12 pages, 9 figures, accepted for publication in PRD. Minor changes, replaced and corrected Figs 4,5,

Some properties of Neg-raising in three sign languages

Neg-raising, the phenomenon whereby a negation in the main clause of a complex construction is interpreted as if belonging to the embedded clause, has been intensively studied in spoken languages. The same cannot be said for sign languages. In this paper, we investigate the properties of Neg-raising constructions in three sign languages: French Sign Language, Italian Sign Language, and Sign Language of the Netherlands.We report on two syntactic tests we applied to disambiguate Neg-raising and non-Negraising readings, showing that Neg-raising constructions have similar properties in the three sign languages that we studied, as well as in comparable constructions in spoken languages. We also discuss some intricate headshake spreading patterns we found in Neg-raising constructions in Sign Language of the Netherlands, a non-manual dominant sign language

A GIANT ANEURYSM OF PROPER HEPATIC ARTERY IN A CRYOGLOBULINEMIC PATIENT ON HEMODIALYSIS: A CASE REPORT.

Introductrion. Hepatic artery aneurysms (HAAs) are unusual vascular lesions often associated with many different pathological conditions. Most of reported cases are described in association with connective tissue diseases, such as polyarteritis nodosa and systemic lupus erythematosus. Case report. We observed a 52-year-old man with hypertension and HCV-related cryoglobulinemia complicated by end stage renal disease on replacement therapy by hemodialysis. He was admitted to our hospital because of the worsening of blood pressure values (170/110 mmHg) associated to new onset abdominal pain. After an initial physical examination, that showed a periumbelical bruit associated to a pulsatile mass in right hypocondrium, an abdominal ultrasound was performed with evidence of aneurysms of both the right branch (diameter max 4,5 cm) and the left branch (diameter max 1.5 cm) of the hepatic artery. An abdominal CT study was also performed and it confirmed the diagnosis of right intrahepatic artery aneurysm with partially thrombosed area in its peripheral distal portion. Discussion. Many different factors can contribute to the aneurysm formation in this patient. Vasculitic involvement due to cryoglobulinemic disease, therapy with steroid drugs, inflammatory state associated to HCV-related hepatitis, chronic kidney disease and replacement therapy by hemodialysis may all be involved in the development of the aneurysmatic hepatic lesion

Modeling normative kinetic perimetry isopters using mixed-effects quantile regression

Kinetic perimetry is used to quantify visual field size/sensitivity. Clinically, perimetry can be used to diagnose and monitor ophthalmic and neuro-ophthalmic disease. Normative data are integral to the interpretation of these findings. However, there are few computational developments that allow clinicians to collect and analyze normative data from kinetic perimeters. In this article we describe an approach to fitting kinetic responses using linear quantile mixed models. Analogously to traditional linear mixed-effects models for the mean, linear quantile mixed models account for repeated measurements taken from the same individual, but differently from linear mixed-effects models, they are more flexible as they require weaker distributional assumptions and allow for quantile-specific inference. Our approach improves on parametric alternatives based on normal assumptions. We introduce the R package kineticF, a freely available and open-access resource for the analysis of perimetry data. Our proposed approach can be used to analyze normative data from further studies