Williams V.F.,DRS Research
Journal of Public Health Management and Practice | Year: 2016
PURPOSE:: Young adulthood is an important period for preventing the establishment of negative health behaviors that can influence trajectories to chronic disease and early death. Given the evolving nature of educational attainment and income variation during this developmental period, identifying indicators of socioeconomic status (SES) remains a challenge. This study examines measures of subjective and objective indicators of SES to predict health risk for young adults. METHODS:: This study uses data from the Truth Initiative Young Adult Cohort Study from respondents aged 18 to 34 years who completed 3 consecutive surveys between June 2011 and August 2012 (n = 2182). Analyses were conducted to compare a measure of subjective financial situation (SFS) to commonly used SES measures for adults and adolescents. Age-stratified, multivariable logistic regression was used to model the relationship between 5 SES indicators (SFS, household income, respondent education, parental education, and subjective childhood financial situation) and dichotomized versions of 3 health status measures (body mass index, self-reported health status, and quality of life), controlling for gender, race/ethnicity, and region. RESULTS:: Findings indicate that SFS is associated with other commonly used SES measures. Prospective associations with health outcomes revealed that SFS is a stronger predictor of health outcomes among young adults aged 18 to 24 years as compared with other SES measures. CONCLUSION:: This study provides evidence that subjective financial situation may be more robust than traditional SES indicators in predicting health outcomes among young adults, particularly for 18- to 24-year-olds, and should be considered a viable candidate measure for assessing SES among this age group. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.
Elmasry H.,DRS Research
Journal of Head Trauma Rehabilitation | Year: 2016
OBJECTIVE:: To determine the preenlistment and early service risk factors for traumatic brain injury (TBI)-related disability in Army and Marine Corps service members. DESIGN:: Matched case-control design. MAIN OUTCOME:: TBI disability discharges. SUBJECTS:: Army and Marine Corps service members with an enlistment record and disability discharge for TBI were included as cases. Controls were selected from the enlisted population with no disability evaluation record and were matched on fiscal year of enlistment, sex, and service at a ratio of 5:1. RESULTS:: Older age at enlistment resulted in a significantly increased risk for TBI disability in the crude and adjusted models (adjusted odds ratio [aOR] = 1.49; 95% confidence interval [CI], 1.16-1.91). An enlistment military occupational specialty (MOS) with a combat arms designation resulted in an almost 3-fold increased odds of TBI disability compared with other MOS categories (aOR = 2.75; 95% CI, 2.46-3.09). This remained a significant risk factor for TBI disability in the multivariate model (aOR = 2.74; 95% CI, 2.45-3.08). CONCLUSION:: Results from this study help inform the existing body of military TBI research by highlighting the preenlistment demographic and early service risk factors for TBI disability. Further research into the role of age on TBI disability in the military is merited. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.
Shin J.,Yonsei University |
Lee J.S.,Yonsei University |
Hann S.-K.,DRS Research |
Oh S.H.,Yonsei University
British Journal of Dermatology | Year: 2012
Background Vitiligo is a common acquired depigmentation disorder caused by the loss of melanocytes. Despite the numerous treatment modalities available for vitiligo, responses to treatment are still unsatisfactory. For this reason, new treatment modalities and approaches are needed. Objectives To investigate the effects of fractional carbon dioxide (CO 2) laser therapy followed by systemic narrowband ultraviolet B (NB-UVB) phototherapy on nonsegmental vitiligo (NSV) as a prospective and randomized left-right comparative study. Methods Ten patients with NSV who presented symmetrical vitiligo lesions with no further improvement despite more than 1 year of conventional treatment were enrolled. Two sessions of half-body fractional CO 2 laser therapy were performed at a 2-month interval. NB-UVB phototherapy was then administered to the entire body 5 days after each fractional laser treatment twice a week, increasing the dose incrementally by 15% at each session. Objective clinical assessments were made by two blinded dermatologists using a quartile grading scale, and the patients' overall satisfaction was evaluated using a 10-point visual analogue scale. Results Two months after the last treatment, mean improvement scores, assessed by physicians, were significantly higher for those treated with half-body fractional CO 2 laser therapy followed by NB-UVB phototherapy, compared with those treated with NB-UVB alone (P = 0·034). In addition, according to subjective assessment, the half-body laser treatment followed by NB-UVB showed significantly higher improvements compared with NB-UVB treatment alone (P = 0·023). Noticeable adverse events, such as infection, scarring and Koebner phenomenon, were not found in any patient. Conclusions This study suggests that fractional CO 2 laser therapy followed by NB-UVB phototherapy could be used effectively and safely as an alternative modality for the treatment of refractory vitiligo. © 2011 The Authors. BJD © 2011 British Association of Dermatologists.
Kim D.-Y.,Yonsei University |
Oh S.H.,Yonsei University |
Hann S.-K.,DRS Research
British Journal of Dermatology | Year: 2011
Background: The origin of the distribution of segmental vitiligo (SV) has not yet been clearly elucidated. Segmental configurations of cutaneous disorders have been explained using two main interpretations, i.e. following either dermatomal or blaschkolinear distributions. However, facial SV does not always correspond to either of these distributions. Objectives: We classified facial SV into several distinctive subtypes according to specific distributions based on long-term observations. Methods: In total, 257 patients with facial SV were included, all of whom were closely observed for more than 1 year. The distribution patterns of facial SV were classified according to morphological similarities based on clinical observations. Results: The lesions of facial SV were categorized into six subtypes: types I-a and I-b, and types II-V. Type I-a and type IV broadly involved the mid-level face from the forehead to the lower cheek, but type IV lesions selectively appeared on the right side of the face and did not cross the midline. Type I-b lesions chiefly involved the forehead and scalp hair. Types II and III involved the lower face and, frequently, the neck area, and type V lesions were distributed mostly around the right orbital area. The most frequent type of lesion in this study was type I-a (28·8%), followed by types II (16·0%), III (14·4%), IV (10·9%), I-b (10·5%) and V (8·6%). Conclusions: Newly established patterns of facial SV may be valuable for certain aspects of prognosis, such as the likely degree and path of lesion spreading. © 2011 British Association of Dermatologists.
Febvey O.,DRS Research
Journal of Occupational and Environmental Medicine | Year: 2016
OBJECTIVE:: The aim of this study was to assess the risk of childhood central nervous system (CNS) tumors associated with parental occupational pesticide exposure. METHODS:: We pooled three population-based case-control studies from France, Germany, and the United Kingdom. Cases were children below 15 years of age with CNS tumors; controls were matched by gender and age. A general population job-exposure matrix assessed parental occupational pesticide exposure. Logistic regressions estimated odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS:: The study included 1361 cases and 5498 controls. Prevalence of maternal occupational pesticide exposure during pregnancy was low and no association with childhood CNS tumors was detected (OR 0.76, 95% CI: 0.41 to 1.41). Around conception, OR for childhood CNS tumors associated with paternal occupational pesticide exposure was 0.71 (95% CI: 0.53 to 0.95). CONCLUSION:: Our results do not suggest a role of parental occupational pesticide exposure in the etiology of childhood CNS tumors. Copyright © 2016 by the American College of Occupational and Environmental Medicine
Agency: Department of Energy | Branch: | Program: STTR | Phase: Phase II | Award Amount: 999.98K | Year: 2014
This project is about development of novel multilayer dielectric capacitors via thermal spray coating route. Use of this technology will enable mass production of multilayer ceramic capacitors at lower cost.
Agency: Department of Defense | Branch: Missile Defense Agency | Program: SBIR | Phase: Phase I | Award Amount: 99.91K | Year: 2013
High performance solid and liquid propulsion systems are subject to severe operating conditions and are required to perform at appreciably higher use-temperatures. Rocket nozzles must withstand an extremely rapid temperature increase in a highly corrosive atmosphere while maintaining a high degree of integrity. Current nozzles are often made from a variety of metal alloys, carbon-carbon or carbon phenolic composites, which are able to withstand high temperature and pressure environments. However, the phenolic nozzle exit cones typically experience extreme heat during operation and lead to premature failure of the bond line joints and housing components during firing and heat soak. This effect is more pronounced in the dual pulse rocket motors where additional heat soak is experienced due to presence of Inter Pulse Delay (IPD). The additional delay results into extra heat soak there by possible damaging the housing components such as flex bearing. In order to address these aspects, in this phase I proposal we intend to develop novel high temperature thermal barrier coatings using integrated metal bond layer and thermal barrier ceramic top layer technology on Carbon Cloth Phenolic base material.
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 150.00K | Year: 2012
ABSTRACT: The main goal of the present Phase I proposal is to examine the feasibility of applying the HVOF ID gun process to coat the internal surfaces of the landing gear components. HVOF is an environmentally friendly process compared to hard chrome plating in terms of hex-Cr elimination and avoiding hydrogen embrittlement. Due to their excellent erosion, corrosion and high temperature wear resistance, HVOF WC-Co based coatings will be carried out in Phase I. Various HVOF guns such as HVOF JetKote, Thermico"s ID Cool Flow gun and Merlyn (A-Flame)briefcase ID gun will be tried. Hence, in this phase I SBIR program, DRS Research in collaboration with Plasma Technology Inc. and General Dynamics team, intends to demonstrate the feasibility of use of modified HVOF process technology for effective realization of WC-17Co and WC-10Co-4Cr based coatings in ID bores. BENEFIT: Successful completion of the phase I program will set the stage of commercialization of the ID coating technology to not only landing gear applications, but also to automotive industry, oil and gas exploration industry etc. Deep hole drilling tubes face not only excessive wear due to sand and other particulates, but also are exposed to corrosive media leading to heavy wear. ID gun coating technology developed during this program will address these problems for the multi billion dollar deep hole exploration industry.
Agency: Department of Energy | Branch: | Program: STTR | Phase: Phase I | Award Amount: 149.99K | Year: 2013
The main focus of this STTR is to design, develop, and evaluate high temperature capacitors using novel thermal spray coating processes, which will allow the devices to meet the performance requirements. Multilayer coating architecture will be adopted and the electrodes and dielectric material selections will be screened in Phase I to note material compatibility and high temperature performance. The Center for Dielectrics Studies, CDS at Penn State University, over the last 3-6 years, has discovered a number of important new dielectric materials for co- firing and multilayer assembly. These materials have shown a wide variety of polarization phenomena and provide different opportunities for high temperature dielectrics, some of which have already gone through pilot line testing, and have been introduced as potential new multilayer ceramic capacitors for high temperature applications. There is, very good reliability performance at 150 oC, but so far there are still issues in long time performance at 200 and 250 oC, and the second- and third-generation high temperature capacitors require a major innovation in approach and in materials to improve the mean time to failure performance at high field and high temperatures. Capacitor technology in general, requires characterization tools and theories to improve the optimization and life-testing for high temperature operation. We are outlining a novel processing strategy with a variety of high performance dielectric oxides that could provide a revolutionary approach to obtain high temperature capacitors independent of the multilayer tape-casting route, but with a cost effective deposition technique that is scalable for high volume cost effect production. The Phase I will consider the deposition of selected dielectrics with single layers and also show the possibility of multilayer production with the shadow mask approach. Data from phase I on selected dielectrics will then be taken to focus efforts on prototyped larger capacitors with more rigor including reliability studies in phase II. The overall capacitor architecture will be designed using the novel thermal spray coating process and is based on multilayer coating structure. The form factor will be realized using a novel shadow mask technology to provide unique microstructures and processing routes that permit low ESR and ESL, and high temperature reliability. The thermal spray method allows low temperature deposition of both the dielectric material and the electrode material in a sequential and rapid processing route that avoids the complexities of binder removal, sintering etc. Commercial Applications and Other Benefits: Application areas for this type of capacitor technologies can be switch mode power supplies, supplies, linear accelerator capacitors, ac-dc invertors, pulse power, energy storage, electric armor etc. The attraction of this proposed fabrication approach would be the ability to fabricated larger high capacitance devices, where the convention processing problems such as binder removal, electrode interactions in electrode ceramic interfaces and co-firing transient stresses limit larger device fabrication.
Agency: Department of Energy | Branch: | Program: STTR | Phase: Phase I | Award Amount: 149.97K | Year: 2013
The extreme operating conditions experienced by many moving mechanical components in aerospace and automotive engines require the uses of high-performance materials and lubricants. Current oil-based lubricants degrade rapidly under such conditions and become useless, especially at high temperatures. As a result, many moving components of engines that are run at high temperatures to improve their performance and efficiency tend to wear out rapidly and to require frequent replacement. Under such conditions, these lubricants with much higher temperature durability are urgently needed. It appears that the manufacturing of oil or liquid-based lubricants is not possible; while the development and implementation of long-lasting solid lubricants can be considered as a viable option. Hence there is a need for finding an enabling technology as a solution for such complex issues in aerospace turbine and automotive bearing applications. One solution to extend engine life is with the implementation of a low friction, high temperature stable, and low wear coatings to the component surface that can perform under extreme conditions. Solid lubricant coating offers a solution for diverse applications involving extreme and difficult running conditions. These coatings make bearings slide more easily and help engine parts last longer and thereby enabling improved energy efficiency and longer durability. The coatings effectively reduce friction, have high hardness and wear resistance, and strongly bond to the bearing steel, providing long operating endurance. A crystal-chemical approach has been proposed recently to classify lubricious oxides on the basis of lubrication performance and operational limits. The principle of the crystal-chemical approach is based essentially on the ionic potential of an oxide and is defined as = Z/r, where Z is the cationic charge and r is the radius of the cation. Erdemir  proposed that using this principle, one can establish model relationship(s) between the quantum-chemical characteristics and the lubricity of oxides at high temperatures. Specifically, it is possible to establish a correlation between the ionic potential or the cationic field strength of an oxide and its shear rheology, and hence its lubricity. Table I below shows some of the examples of oxides combinations and their ionic potentials, which will be investigated during the Phase I STTR program. Commercial Applications and Other Benefits Development of solid lubricant protective coating systems which show improved performance at elevated temperatures, will result in improving the current tooling life and efficiency thereby improving overall productivity. The crystal-chemical approach can be used to predict the extent of adhesive interactions between two or more oxides at a sliding interface; hence, it can be used to predict frictional performance. Based on this model, certain complex oxides and oxide-fluorides (i.e., ZnO/SnO/SrF2, NiO/BaTiO3, MgO/ZnO/CaF2, and NiO/SrF2) show enhanced lubricity at elevated temperatures. The dry lubricant ceramic coatings are of interest to our strategic partner Capstone for bearing components applications. Also, Federal Mogul and General Motors has expressed their interest in evaluating these coatings for the piston ring, pins, crack shafts, dies and molds etc.. Being ceramic in nature these coatings can be finish ground and sealed per customer specification. Hence it is proposed to evaluate various combinations of mixed oxide coatings for their room temperature and elevated temperature wear resistance and friction coefficient during the phase I and phase II programs. During phase III, when fully developed, optimized and implemented in engines, such oxide coatings can prevent friction, wear, and oxidation related degradations and increase efficiency, durability and environmental compatibility of these engines.