Double layer in ionic liquids: Overscreening vs. crowding

We develop a simple Landau-Ginzburg-type continuum theory of solvent-free ionic liquids and use it to predict the structure of the electrical double layer. The model captures overscreening from short-range correlations, dominant at small voltages, and steric constraints of finite ion sizes, which prevail at large voltages. Increasing the voltage gradually suppresses overscreening in favor of the crowding of counterions in a condensed inner layer near the electrode. The predicted ion profiles and capacitance-voltage relations are consistent with recent computer simulations and experiments on room-temperature ionic liquids, using a correlation length of order the ion size.Comment: 4 pages + supplementary informatio

A photoionized Herbig-Haro object in the Orion nebula

The spectra of Herbig Haro objects are usually characteristic of ionization and excitation in shock-heated gas, whether an internal shock in an unsteady outflow or a bow shock interface with the interstellar medium. We examine the eastern-most shock -- the leading optically visible shock -- of a Herbig Haro outflow (HH 529) seen projected on the face of the Orion Nebula, using deep optical echelle spectroscopy, showing that the spectrum of this gas is consistent with photoionization by $\theta^1$ Ori C. By modeling the emission lines, we determine a gas-phase abundance of Fe which is consistent with the depleted (relative to solar) abundance found in the Orion nebula -- evidence for the presence of dust in the nebula and therefore in the Herbig Haro outflow. The spectrum also allows for the calculation of temperature fluctuations, $t^2$, in the nebula and the shock. These fluctuations have been used to explain discrepancies between abundances obtained from recombination lines versus those obtained from collisionally-excited lines, although to date there has not been a robust theory for how such large fluctuations ($t^2 > 0.02$) can exist.Comment: 50 pages, 8 figures, To be published in Ap

The longitudinal association between externalizing and internalizing problems : an exploration of the Dual Failure Model

Abstract : The Dual Failure Model suggests that peer victimization (social failure) and academic difficulties (academic failure) mediate the association between externalizing and later internalizing problems. The present study sought to better understand why children with externalizing problems develop later internalizing problems by testing the Dual Failure Model using a sample of 744 children (aged 6 to 10 at Time 1 [T1]), of whom 434 (44.7% girls) presented with high levels of conduct problems at study inception. Both parent and teacher ratings of externalizing and internalizing problems support the social failure pathway, but not the academic failure pathway. Children with externalizing behaviors at T1 who developed internalizing problems 2 years later did so via their experiences of peer victimization. These results apply for both boys and girls and do not vary according to child age at T1 or the level of conduct problems at study inception. These findings underscore the importance of early screening and intervention for externalizing behavioral problems in order to reduce subsequent peer victimization and internalizing problems. Findings regarding the consequences of internalizing are also discussed

Human papillomavirus mediated inhibition of DNA damage sensing and repair drives skin carcinogenesis

Background: The failure to mount an effective DNA damage response to repair UV induced cyclobutane pyrimidine dimers (CPDs) results in an increased propensity to develop cutaneous squamous cell carcinoma (cSCC). High-risk patient groups, such as organ transplant recipients (OTRs) frequently exhibit field cancerization at UV exposed body sites from which multiple human papillomavirus (HPV)-associated cSCCs develop rapidly, leading to profound morbidity and increased mortality. In vitro molecular evidence indicates that HPV of genus beta-papillomavirus (β-PV) play an important role in accelerating the early stages of skin tumorigenesis. Methods: We investigated the effects of UV induced DNA damage in murine models of β-PV E6 oncoprotein driven skin tumorigenesis by crossing K14-HPV8-E6wt mice (developing skin tumors after UV treatment) with K14-CPD-photolyase animals and by generating the K14-HPV8-E6-K136N mutant mouse strain. Thymine dimers (marker for CPDs) and γH2AX (a marker for DNA double strand breaks) levels were determined in the murine skin and organotypic skin cultures of E6 expressing primary human keratinocytes after UV-irradiation by immunohistochemistry and in cell lines by In Cell Western blotting. Phosphorylation of ATR/Chk1 and ATM were assessed in cell lines and organotypic skin cultures by Western blots and immunohistochemistry. Results: Skin tumor development after UV-irradiation in K14-HPV8-E6wt mice could completely be blocked through expression of CPD-photolyase. Through quantification of thymine dimers after UV irradiation in cells expressing E6 proteins with point mutations at conserved residues we identified a critical lysine in the

Remote clinical consultations in restorative dentistry: A clinical service evaluation study

Introduction Specialist consultant services in the UK NHS provide a decision-making support service to other health professionals. There is a drive to deliver this service in a more patient-centred, cost-effective and efficient manner. Remote clinical consultations (RCC), using secure, live, super-fast internet connectivity and high-resolution, multi-channel audio-visual streaming, has the potential for the delivery of this service. Aim To conduct a clinical service evaluation to assess the viability and efficiency of conducting a RCC for the management of primary care referrals in restorative dentistry, compared to an in-person consultation. Design A RCC was conducted for every participating patient and immediately followed with a 'verification' in-person consultation. Materials and method Twenty-three patients of even gender distribution participated in this study across the three specialisms of restorative dentistry. A thematic questionnaire was completed by each member of the study intervention team and the patient after each consultation. Results In all the cases, the consultant was able to conduct an effective and safe clinical consultation, not inferior to an in-person process, regardless of gender and age. The GDP, the nurse and the patient were able to participate effectively in the process and with each other. Conclusion This proof-of-concept study suggests that the RCC concept is a feasible way of delivering specialist consultations in restorative dentistry with high levels of patient acceptability and that it can be delivered in a practical and simple manner

The prevalence of cubital tunnel syndrome: A cross-sectional study in a U.S. metropolitan cohort

BACKGROUND: Although cubital tunnel syndrome is the second most common peripheral mononeuropathy (after carpal tunnel syndrome) encountered in clinical practice, its prevalence in the population is unknown. The objective of this study was to evaluate the prevalence of cubital tunnel syndrome in the general population. METHODS: We surveyed a cohort of adult residents of the St. Louis metropolitan area to assess for the severity and localization of hand symptoms using the Boston Carpal Tunnel Questionnaire Symptom Severity Scale (BCTQ-SSS) and the Katz hand diagram. We identified subjects who met our case definitions for cubital tunnel syndrome and carpal tunnel syndrome: self-reported hand symptoms associated with a BCTQ-SSS score of >2 and localization of symptoms to the ulnar nerve or median nerve distributions. RESULTS: Of 1,001 individuals who participated in the cross-sectional survey, 75% were women and 79% of the cohort was white; the mean age (and standard deviation) was 46 ± 15.7 years. Using a more sensitive case definition (lax criteria), we identified 59 subjects (5.9%) with cubital tunnel syndrome and 68 subjects (6.8%) with carpal tunnel syndrome. Using a more specific case definition (strict criteria), we identified 18 subjects (1.8%) with cubital tunnel syndrome and 27 subjects (2.7%) with carpal tunnel syndrome. CONCLUSIONS: The prevalence of cubital tunnel syndrome in the general population may be higher than that reported previously. When compared with previous estimates of disease burden, the active surveillance technique used in this study may account for the higher reported prevalence. This finding suggests that a proportion of symptomatic subjects may not self-identify and may not seek medical treatment. CLINICAL RELEVANCE: This baseline estimate of prevalence for cubital tunnel syndrome provides a valuable reference for future diagnostic and prognostic study research and for the development of clinical practice guidelines

Improving Predictions for Helium Emission Lines

We have combined the detailed He I recombination model of Smits with the collisional transitions of Sawey & Berrington in order to produce new accurate helium emissivities that include the effects of collisional excitation from both the 2 (3)S and 2 (1) S levels. We present a grid of emissivities for a range of temperature and densities along with analytical fits and error estimates. Fits accurate to within 1% are given for the emissivities of the brightest lines over a restricted range for estimates of primordial helium abundance. We characterize the analysis uncertainties associated with uncertainties in temperature, density, fitting functions, and input atomic data. We estimate that atomic data uncertainties alone may limit abundance estimates to an accuracy of 1.5%; systematic errors may be greater than this. This analysis uncertainty must be incorporated when attempting to make high accuracy estimates of the helium abundance. For example, in recent determinations of the primordial helium abundance, uncertainties in the input atomic data have been neglected.Comment: ApJ, accepte

G313.3+00.3: A New Planetary Nebula discovered by the Australia Telescope Compact Array and the Spitzer Space Telescope

We present a new planetary nebula, first identified in images from the Australia Telescope Compact Array, although not recognized at that time. Recent observations with the Spitzer Space Telescope during the GLIMPSE Legacy program have rediscovered the object. The high-resolution radio and infrared images enable the identification of the central star or its wind, the recognition of the radio emission as thermal, and the probable presence of polycylic aromatic hydrocarbons in and around the source. These lead to the conclusion that G313.3+00.3 is a planetary nebula. This object is of particular interest because it was discovered solely through radio and mid-infrared imaging, without any optical (or near-infrared) confirmation, and acts as a proof of concept for the discovery of many more highly extinguished planetary nebulae. G313.3+00.3 is well-resolved by both the instruments with which it was identified, and suffers extreme reddening due to its location in the Scutum-Crux spiral arm.Comment: 18 pages, LaTeX (aastex), incl. 8 PostScript (eps) figures and 1 table. Accepted by ApJ (Part 1

Deviations from He I Case B Recombination Theory and Extinction Corrections in the Orion Nebula

We are engaged in a comprehensive program to find reliable elemental abundances in and to probe the physical structure of the Orion Nebula, the brightest and best-resolved H II region. In the course of developing a robust extinction correction covering our optical and ultraviolet FOS and STIS observations, we examined the decrement within various series of He I lines. The decrements of the 2^3S-n^3P, 2^3P-n^3S and 3^3S-n^3P series are not in accord with caseB recombination theory. None of these anomalous He I decrements can be explained by extinction, indicating the presence of additional radiative transfer effects in He I lines ranging from the near-IR to the near-UV. CLOUDY photoionization equilibrium models including radiative transfer are developed to predict the observed He I decrements and the quantitative agreement is quite remarkable. Following from these results, select He I lines are combined with H I and [O II] lines and stellar extinction data to validate a new normalizable analytic expression for the wavelength dependence of the extinction. In so doing, the He+/H+ abundance is also derived.Comment: 42 pages, 10 figures. To be published in Ap