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Sample records for 2-year study conducted

  1. MST with Conduct Disordered Youth in Sweden: Costs and Benefits after 2 Years

    ERIC Educational Resources Information Center

    Olsson, Tina M.

    2010-01-01

    Objectives: The purpose of this study was to investigate the costs and benefits associated with multisystemic therapy (MST) for conduct disordered youth, 2 years following intake. Methods: The study employed a secondary analysis of 156 youth enrolled in a randomized trial assessing the psychosocial and behavioral outcomes of MST. Results: MST cost…

  2. Many Kidney Transplant Patients Land in ER Within 2 Years: Study

    MedlinePlus

    ... news/fullstory_157959.html Many Kidney Transplant Patients Land in ER Within 2 Years: Study Findings show need to coordinate care after organ transplant, researcher says To use the sharing features on this page, please enable ...

  3. Learning, Memory, and Executive Function in New MDMA Users: A 2-Year Follow-Up Study

    PubMed Central

    Wagner, Daniel; Tkotz, Simon; Koester, Philip; Becker, Benjamin; Gouzoulis-Mayfrank, Euphrosyne; Daumann, Joerg

    2015-01-01

    3,4-Methylenedioxymethamphetamine (MDMA) is associated with changes in neurocognitive performance. Recent studies in laboratory animals have provided additional support for the neurodegeneration hypothesis. However, results from animal research need to be applied to humans with caution. Moreover, several of the studies that examine MDMA users suffer from methodological shortcomings. Therefore, a prospective cohort study was designed in order to overcome these previous methodological shortcomings and to assess the relationship between the continuing use of MDMA and cognitive performance in incipient MDMA users. It was hypothesized that, depending on the amount of MDMA taken, the continued use of MDMA over a 2-year period would lead to further decreases in cognitive performance, especially in visual paired association learning tasks. Ninety-six subjects were assessed, at the second follow-up assessment: 31 of these were non-users, 55 moderate-users, and 10 heavy-users. Separate repeated measures analyses of variance were conducted for each cognitive domain, including attention and information processing speed, episodic memory, and executive functioning. Furthermore, possible confounders including age, general intelligence, cannabis use, alcohol use, use of other concomitant substances, recent medical treatment, participation in sports, level of nutrition, sleep patterns, and subjective well-being were assessed. The Repeated measures analysis of variance (rANOVA) revealed that a marginally significant change in immediate and delayed recall test performances of visual paired associates learning had taken place within the follow-up period of 2 years. No further deterioration in continuing MDMA-users was observed in the second follow-up period. No significant differences with the other neuropsychological tests were noted. It seems that MDMA use can impair visual paired associates learning in new users. However, the groups differed in their use of concomitant use of

  4. Learning, Memory, and Executive Function in New MDMA Users: A 2-Year Follow-Up Study.

    PubMed

    Wagner, Daniel; Tkotz, Simon; Koester, Philip; Becker, Benjamin; Gouzoulis-Mayfrank, Euphrosyne; Daumann, Joerg

    2015-01-01

    3,4-Methylenedioxymethamphetamine (MDMA) is associated with changes in neurocognitive performance. Recent studies in laboratory animals have provided additional support for the neurodegeneration hypothesis. However, results from animal research need to be applied to humans with caution. Moreover, several of the studies that examine MDMA users suffer from methodological shortcomings. Therefore, a prospective cohort study was designed in order to overcome these previous methodological shortcomings and to assess the relationship between the continuing use of MDMA and cognitive performance in incipient MDMA users. It was hypothesized that, depending on the amount of MDMA taken, the continued use of MDMA over a 2-year period would lead to further decreases in cognitive performance, especially in visual paired association learning tasks. Ninety-six subjects were assessed, at the second follow-up assessment: 31 of these were non-users, 55 moderate-users, and 10 heavy-users. Separate repeated measures analyses of variance were conducted for each cognitive domain, including attention and information processing speed, episodic memory, and executive functioning. Furthermore, possible confounders including age, general intelligence, cannabis use, alcohol use, use of other concomitant substances, recent medical treatment, participation in sports, level of nutrition, sleep patterns, and subjective well-being were assessed. The Repeated measures analysis of variance (rANOVA) revealed that a marginally significant change in immediate and delayed recall test performances of visual paired associates learning had taken place within the follow-up period of 2 years. No further deterioration in continuing MDMA-users was observed in the second follow-up period. No significant differences with the other neuropsychological tests were noted. It seems that MDMA use can impair visual paired associates learning in new users. However, the groups differed in their use of concomitant use of

  5. A 2-year longitudinal study of prospective predictors of pathological Internet use in adolescents.

    PubMed

    Strittmatter, Esther; Parzer, Peter; Brunner, Romuald; Fischer, Gloria; Durkee, Tony; Carli, Vladimir; Hoven, Christina W; Wasserman, Camilla; Sarchiapone, Marco; Wasserman, Danuta; Resch, Franz; Kaess, Michael

    2016-07-01

    Longitudinal studies of prospective predictors for pathological Internet use (PIU) in adolescents as well as its course are lacking. This three-wave longitudinal study was conducted within the framework of the European Union-funded project "Saving and Empowering Young Lives in Europe" over a 2-year period. The sample consisted of 1444 students at the baseline investigation (T0); 1202 students after 1 year (T1); and 515 students after 2 years (T2). Structured self-report questionnaires were administered at all three time points. PIU was assessed using the Young Diagnostic Questionnaire (YDQ). In addition, demographic (i.e., gender), social (i.e., parental involvement), psychological (i.e., emotional problems), and Internet use-related factors (i.e., online activities) were assessed as prospective predictors. The prevalence of PIU was 4.3 % at T0, 2.7 % at T1 and 3.1 % at T2. However, only 3 students (0.58 %) had persistent categorical PIU (YDQ score of ≥5) over the 2-year period. In univariate models, a variety of variables that have been previously identified in cross-sectional investigations predicted PIU at T2. However, multivariate regression demonstrated that only previous PIU symptoms and emotional problems were significant predictors of PIU 2 years later (adjusted R (2) 0.23). The stability of categorical PIU in adolescents over 2 years was lower than previously reported. However, current PIU symptoms were the best predictor of later PIU; emotional symptoms also predicted PIU over and above the influence of previous problematic Internet use. Both PIU symptoms and emotional problems may contribute to the vicious cycle that supports the perpetuation of PIU. PMID:26526444

  6. Effectiveness of a tinnitus management programme: a 2-year follow-up study

    PubMed Central

    Gudex, Claire; Skellgaard, Preben H; West, Torben; Sørensen, Jan

    2009-01-01

    Background Tinnitus impairs the possibility of leading a normal life in 0.5–1% of the population. While neither medical nor surgical treatment appears effective, counselling may offer some relief. An intervention combining counselling and hearing devices is offered to clients referred to the Centre for Help Aids and Communication (CHC) in southern Denmark. The aims of this exploratory study were to examine i) the characteristics of CHC's clients and their tinnitus, ii) the effectiveness of the treatment, and iii) whether particular client groups benefit more than others. Methods One hundred new clients presenting with tinnitus completed the Tinnitus Handicap Inventory (THI) three times – before their first consultation, after one month and after 1–2 years. The scores were tested for significant differences over time using tests for paired data. Logistic regression was used to examine factors associated with a clinically important difference (i.e. THI score improvement of at least 20 points). Results At final follow-up, total THI score was significantly lower than baseline, i.e. 29.8 (CI 25.5–34.2) vs. 37.2 (CI 33.1–37.2), p < 0.01. The programme achieved a clinically important difference for 27% and 24% of the clients one month and 1–2 years after the first consultation, respectively. It appeared that greater improvement in THI score was related to higher baseline THI score and possibly also to treatment by a particular CHC therapist. The absolute reduction in mean THI score after 1–2 years for clients with moderate and severe handicap was 14 and 20 points, respectively, i.e. similar to that previously reported for TRT (14–28 points). The cost of the current programme was approximately 200 EUR per client. Conclusion The tinnitus management programme appeared to provide significant benefit to many clients at a relatively low cost. It would be useful to conduct a randomised controlled study comparing the current programme with alternative forms of

  7. Treatment costs associated with interventional cancer clinical trials conducted at a single UK institution over 2 years (2009–2010)

    PubMed Central

    Liniker, E; Harrison, M; Weaver, J M J; Agrawal, N; Chhabra, A; Kingshott, V; Bailey, S; Eisen, T G G; Corrie, P G

    2013-01-01

    Background: The conduct of clinical trials should be an integral part of routine patient care. Treating patients in trials incurs additional costs over and above standard of care (SOC), but the extent of the cost burden is not known. We undertook a retrospective cost attribution analysis to quantitate the treatment costs associated with cancer clinical trial protocols conducted over a 2 year period. Methods: All patients entered into oncology (non-haematology) clinical trials involving investigational medicinal products in 2009 and 2010 in a single UK institution were identified. The trial protocols on which they were treated were analysed to identify the treatment costs for the experimental arm(s) of the trial and the equivalent SOC had the patient not been entered in the trial. The treatment cost difference was calculated by subtracting the experimental treatment cost from SOC cost. For randomised trials, an average treatment cost was estimated by taking into account the number of arms and randomisation ratio. An estimate of the annual treatment costs was calculated. Results: A total of 357 adult oncology patients were treated on 53 different trial protocols: 40 phase III, 2 randomised II/III and 11 phase II design. A total of 27 trials were academic, non-commercial sponsored trials and 26 were commercial sponsored trials. When compared with SOC, the average treatment cost per patient was an excess of £431 for a non-commercial trial (range £6393 excess to £6005 saving) and a saving of £9294 for a commercial trial (range £0 to £71 480). There was an overall treatment cost saving of £388 719 in 2009 and £496 556 in 2010, largely attributable to pharmaceutical company provision of free drug supplies. Conclusion: On an average, non-commercial trial protocols were associated with a small per patient excess treatment cost, whereas commercial trials were associated with a substantially higher cost saving. Taking into account the total number of patients

  8. Improving Social Competence through Emotion Knowledge in 2-Year-Old Children: A Pilot Study

    ERIC Educational Resources Information Center

    Giménez-Dasí, Marta; Fernández-Sánchez, Marta; Quintanilla, Laura

    2015-01-01

    Research Findings: The goal of this study was to determine the efficacy of an educational intervention program to improve emotion knowledge, emotion regulation, and social competence in 2-year-old Spanish children. This study makes two original contributions because there are no validated education programs for such young children and because it…

  9. Residue level and dissipation pattern of spiromesifen in cabbage and soil from 2-year field study.

    PubMed

    Siddamallaiah, Lekha; Mohapatra, Soudamini

    2016-03-01

    Spiromesifen is a new class of insecticide used for the control of whiteflies and mites which have developed resistance to the more commonly used neonicotinoids. Dissipation pattern of spiromesifen on cabbage was evaluated over 2 years by conducting supervised field studies as per good agricultural practices. Cabbage and soil samples were extracted and purified using modified QuEChERS method and analyzed through gas chromatography (GC). Confirmatory studies were carried out by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The recoveries of spiromesifen from cabbage and soil were between 85.44 and 103.37% with the relative standard deviation (RSD) between 3.2 and 9.4% (n = 6). The limit of detection (LOD) and limit of quantification (LOQ) were 0.003 μg mL(-1) and 0.01 mg kg(-1), respectively. The measurement uncertainties (MUs) were within 9.9-14.9%. Initial residues of spiromesifen on cabbage were 0.640 and 1.549 mg kg(-1) during 2013 and 0.723 and 1.438 mg kg(-1) during 2014 from treatments at standard and double doses of 125 and 250 g active ingredient (a.i.) ha(-1), respectively. Spiromesifen residue dissipation followed first-order rate kinetics, and it degraded within the half-lives of 2.9 and 3.9 days during 2013 and 3.2 and 4.5 days during 2014. The residue levels reached below the maximum residue limit (MRL; 0.02 mg kg(-1)) within 15-17 days at the standard dose and 24-27 days at the double dose. The field soil analyzed at harvest (30 days) was free from spiromesifen residues. Metabolite spiromesifen-enol was not detected in any sample which was confirmed through LC-MS/MS analysis. PMID:26869045

  10. Natrelle 410 Extra-Full Projection Silicone Breast Implants: 2-Year Results from Two Prospective Studies

    PubMed Central

    McGuire, Patricia; Murphy, Diane K.

    2015-01-01

    Background: The safety and effectiveness of the Natrelle Style 410 highly cohesive silicone gel breast implant (Allergan, Inc., Irvine, Calif.) in full or moderate height and projection have been shown in a 10-year study. Extra-full projection implants may be an appropriate option for some women undergoing breast reconstruction. Methods: A total of 2795 women received at least one Natrelle 410 extra-full projection implant (X-style) for breast reconstruction in two similarly designed, prospective, multicenter studies. Data collected for 2 years after implantation in these studies were pooled to evaluate complication rates and subject and physician satisfaction. Results: Most subjects (76.0 percent) underwent bilateral reconstruction; a total of 4912 devices were implanted. Complication rates at 2 years were low. The most common complications were asymmetry (4.8 percent) and capsular contracture (3.3 percent). The cumulative risk of reoperation was 21.6 percent by subject and 16.6 percent by device; the most common reasons for reoperation were scarring (n = 97), asymmetry (n = 89), implant malposition (n = 78), and infection (n = 71). Subject and physician satisfaction rates exceeded 90 percent. At 2 years, 97 percent of physicians reported that the shape of the breast reflected the shape of the implant, and that the breast implant had maintained its original position. Conclusions: The safety profile of the Natrelle 410 extra-full projection implant mirrors that of its moderate projection and full projection counterparts. Both physicians and subjects were highly satisfied with the implants 2 years after surgery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV. PMID:26090764

  11. Efficacy and safety of eculizumab in atypical hemolytic uremic syndrome from 2-year extensions of phase 2 studies

    PubMed Central

    Licht, Christoph; Greenbaum, Larry A; Muus, Petra; Babu, Sunil; Bedrosian, Camille L; Cohen, David J; Delmas, Yahsou; Douglas, Kenneth; Furman, Richard R; Gaber, Osama A; Goodship, Timothy; Herthelius, Maria; Hourmant, Maryvonne; Legendre, Christophe M; Remuzzi, Giuseppe; Sheerin, Neil; Trivelli, Antonella; Loirat, Chantal

    2015-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a rare, possibly life-threatening disease characterized by platelet activation, hemolysis and thrombotic microangiopathy (TMA) leading to renal and other end-organ damage. We originally conducted two phase 2 studies (26 weeks and 1 year) evaluating eculizumab, a terminal complement inhibitor, in patients with progressing TMA (trial 1) and those with long duration of aHUS and chronic kidney disease (trial 2). The current analysis assessed outcomes after 2 years (median eculizumab exposure 100 and 114 weeks, respectively). At all scheduled time points, eculizumab inhibited terminal complement activity. In trial 1 with 17 patients, the platelet count was significantly improved from baseline, and hematologic normalization was achieved in 13 patients at week 26, and in 15 patients at both 1 and 2 years. The estimated glomerular filtration rate (eGFR) was significantly improved compared with baseline and year 1. In trial 2 with 20 patients, TMA event-free status was achieved by 16 patients at week 26, 17 patients at year 1, and 19 patients at year 2. Criteria for hematologic normalization were met by 18 patients at each time point. Improvement of 15 ml/min per 1.73 m2 or more in eGFR was achieved by 1 patient at week 26, 3 patients at 1 year, and 8 patients at 2 years. The mean change in eGFR was not significant compared with baseline, week 26, or year 1. Eculizumab was well tolerated, with no new safety concerns or meningococcal infections. Thus, a 2-year analysis found that the earlier clinical benefits achieved by eculizumab treatment of aHUS were maintained at 2 years of follow-up. PMID:25651368

  12. Age-related light scattering in rat lenses observed in a 2-year inhalation toxicity study.

    PubMed

    Wegener, A; Kaegler, M; Stinn, W

    2002-01-01

    Normal light scattering in the eye is determined primarily by the size of alpha-crystalline molecules. Ageing effects appear as an increase in normal lens light scattering in distinct layers. Subliminal effects of toxins on lens transparency can also cause an increase in light scattering due to protein molecule aggregation before visible opacities appear. Scheimpflug photography of the anterior eye segment with subsequent densitometric image analysis is the method of choice to evaluate such effects. To gain more insight into normal ageing and the potential effects of complex aerosols, a subset of Wistar rats (both sexes) belonging to a larger chronic inhalation toxicity study was documented at baseline and after 2 years with a Topcon SL-45 Scheimpflug camera on Kodak T(max) 400 ISO film. The recording procedure, film development, and microdensitometric image analysis were all performed according to standard protocol. A second group from the same study was documented at the start and after 5 months of a 6-month posttreatment period immediately following the inhalation period. Rats were nose-only exposed for 6 h/day, 7 days/week, for 2 years to low (3 microg/l) or high (10 microg/l) concentrations of room-aged cigarette sidestream smoke or diesel engine exhaust. Control animals were exposed to filtered fresh air. At the baseline examination, there were no relevant differences between groups with respect to corneal density or density of defined layers in the lens capsule (1), epithelium and superficial cortex (2), deep cortex (3), supranuclear layer (4) and nucleus (5). At the 2-year examination, mean corneal density was significantly lower in females than in males. This same trend, although not significant, was also found in most layers of the lens. The most prominent differences in density over time were measured in lens layers 3 and 4, but neither corneal density nor lenticular density showed any consistent treatment-related effects in any of the layers. The data

  13. 2-year outcomes in Initial survivors with Acute Liver failure: Results from a Prospective, Multicenter Study

    PubMed Central

    Fontana, Robert J.; Ellerbe, Caitlyn; Durkalski, Valerie E.; Rangnekar, Amol; Reddy, K. Rajender; Stravitz, Todd; McGuire, Brendan; Davern, Timothy; Reuben, Adrian; Liou, Iris; Fix, Oren; Ganger, Daniel R; Chung, Raymond T.; Schilsky, Mike; Han, Steven; Hynan, Linda S.; Sanders, Corron; Lee, William M.

    2014-01-01

    BACKGROUND The long-term clinical outcomes in initial survivors with acute liver failure (ALF) are not well known. AIMS The aim of the current study is to provide an overview of the 2 year clinical outcomes amongst initial survivors and liver transplant (LT) recipients that were alive 3 weeks after enrollment in the Acute Liver Failure Study Group (ALFSG). METHODS Outcomes in adult ALFSG patients that were enrolled between 1998 and 2010 were reviewed. RESULTS 2-year patient survival was significantly higher in the 262 LT recipients (92.4%) compared to the 306 acetaminophen (APAP) spontaneous survivors (SS) (89.5%) and 200 non-APAP SS (75.5%) (p < 0.0001). The causes of death were similar in the 3 groups but the time to death was significantly longer in the LT recipients (p< 0.0001). Independent predictors of 2-year mortality in the APAP group were a high serum phosphate level and patient age (c-statistic = 0.65 (0.54, 0.76)), patient age and days from jaundice to ALF onset in the non-APAP group (c-statistic =0.69 (0.60, 0.78)), and patient age, days from jaundice, and higher coma grade in the LT recipients (c-statistic=0.74 (0.61, 0.87)). The LT recipients were significantly more likely to be employed and have a higher educational level (p < 0.05). CONCLUSIONS Two-year outcomes in initial survivors of ALF are generally good but non-APAP patients have a significantly lower survival which may relate to pre-existing medical co-morbidities. Spontaneous survivors with APAP overdose experience substantial morbidity during follow-up from ongoing psychiatric and substance abuse issues. PMID:25039930

  14. Stressful work, psychological job strain, and turnover: a 2-year prospective cohort study of truck drivers.

    PubMed

    de Croon, Einar M; Sluiter, Judith K; Blonk, Roland W B; Broersen, Jake P J; Frings-Dresen, Monique H W

    2004-06-01

    Based on a model that combines existing organizational stress theory and job transition theory, this 2-year longitudinal study examined antecedents and consequences of turnover among Dutch truck drivers. For this purpose, self-reported data on stressful work (job demands and control), psychological strain (need for recovery after work and fatigue), and turnover were obtained from 820 drivers in 1998 and 2000. In agreement with the model, the results showed that strain mediates the influence of stressful work on voluntary turnover. Also in conformity with the model, job movement to any job outside the trucking industry (i.e., interoccupational turnover) resulted in a larger strain reduction as compared to job movement within the trucking industry (intraoccupational turnover). Finally, strain was found to stimulate interoccupational turnover more strongly than it stimulated intraoccupational turnover. These findings provide a thorough validation of existing turnover theory and give new insights into the turnover (decision) process. PMID:15161404

  15. Occlusal glass ionomer cermet, resin sandwich and amalgam restorations: a 2-year clinical study.

    PubMed

    Lidums, A; Wilkie, R; Smales, R

    1993-08-01

    This study compared the clinical behavior of a glass ionomer silver cermet (Ketac-Silver), a posterior resin composite (Visio-Molar) used with the "sandwich" technique, and a high-copper amalgam (Dispersalloy) for restoring conventional Class I occlusal cavity preparations. Two dentists placed 116 restorations in the posterior permanent teeth of 35 adults treated at a dental hospital. Restorations were assessed at 6-month intervals over 2 years for bulk loss of material and occlusal wear, surface voids, roughness and cracking, surface and marginal staining, and marginal fracture. Losses of material and surface voids were obvious with the cermet material, with surface crazing or cracking being present in 33% of the restorations. The cermet cannot be recommended as a long-term permanent restorative material if the restorations are likely to be subjected to heavy occlusal stresses and abrasive wear. PMID:7803005

  16. [Influence of sport on isoinertial trunk muscle performance development: a 2 years prospective study].

    PubMed

    Rosset, E Bibbo; Mélot, C; Szpalski, M; Keller, T S; Balagué, F

    2013-07-17

    In this study, we investigate the relationship between either regular sports practice or a non sportive way of life, development of trunk muscle performance and occurrence of lower back pain between male schoolchildren. 93 schoolchildren were recruited, then stratified in 4 groups, according to sport practice or sedentary way of life. Participants were evaluated twice at an interval of 2 years with an interview, a physical examination and an evaluation of trunk muscle performance. We identified that basketball players have significantly better results and perfomance concerning isometric and isoinertial tests of trunk muscles than the other groups. Differences in trunk muscle performance exist following the practice of different types of sport. We can deduce that trunk muscle performance has some sport specificity. PMID:23971327

  17. Study of 2 years follow-up of referral patients with abnormal Pap smear

    PubMed Central

    Behnamfar, Fariba; Zafarbakhsh, Azam; Allameh, Taj-Alsadat

    2015-01-01

    Background: Abnormal Pap smear consists of premalignant or malignant cervical lesions. Many of premalignant cervical lesions will never progress to invasive malignancy, or even may regress over the time. Thus, there is always a risk of overtreatment of patients with an abnormal Pap smear. A long-term follow-up of these patients can reveal final events associated with each subtype of abnormal Pap smear, and, therefore, help us to prevent unnecessary interventions. The aim of our study was to present 2 years follow-up of referral patients with abnormal Pap smear. Materials and Methods: A total of 334 consecutive women aged more than 16 who were referred with an abnormal Pap smear were entered into the study. Patients were followed with biannual Pap smear and annual colposcopy and biopsy for 2 years. Results: At baseline, the majority of patients with abnormal Pap smear were normal on colposcopy and biopsy (68% and 86%, respectively). Six months after first abnormal Pap smear majority of patients in each group showed a significant regress to normal or less invasive lesion (P < 0.001). Twelve patients (4%) had no change in Pap smear, whereas 313 (94%) had at least one stage improvement. Only nine (3%) patients had deteriorated Pap smear after 6 months. All 308 patients who underwent colposcopy and biopsy had normal Pap smear 24 months after the first abnormal Pap smear. Conclusion: Pap smear is associated with a high rate of false-positive results. In addition, the majority of low-grade cervical lesions can spontaneously regress. A long-term follow-up of a patient with abnormal Pap smear can help us to avoid needless interventions. PMID:26958048

  18. Talent identification and early development of elite water-polo players: a 2-year follow-up study.

    PubMed

    Falk, Bareket; Lidor, Ronnie; Lander, Yael; Lang, Benny

    2004-04-01

    The processes of talent detection and early development are critical in any sport programme. However, not much is known about the appropriate strategies to be implemented during these processes, and little scientific inquiry has been conducted in this area. The aim of this study was to identify variables of swimming, ball handling and physical ability, as well as game intelligence, which could assist in the selection process of young water-polo players. Twenty-four players aged 14-15 years underwent a battery of tests three times during a 2-year period, before selection to the junior national team. The tests included: freestyle swim for 50, 100, 200 and 400 m, 100-m breast-stroke, 100-m 'butterfly' (with breast-stroke leg motion), 50-m dribbling, throwing at the goal, throw for distance in the water, vertical 'jump' from the water, and evaluation of game intelligence by two coaches. A comparison of those players eventually selected to the team and those not selected demonstrated that, 2 years before selection, selected players were already superior on most of the swim tasks (with the exception of breast-stroke and 50-m freestyle), as well as dribbling and game intelligence. This superiority was maintained throughout the 2 years. Two-way tabulation revealed that, based on baseline scores, the prediction for 67% of the players was in agreement with the final selection to the junior national team. We recommend that fewer swim events be used in the process of selecting young water-polo players, and that greater emphasis should be placed on evaluation of game intelligence. PMID:15161108

  19. Ankle Sprain Injuries: A 2-Year Prospective Cohort Study in Female Greek Professional Basketball Players

    PubMed Central

    Kofotolis, Nikolaos; Kellis, Eleftherios

    2007-01-01

    Context: Ankle sprains are a common basketball injury. Therefore, examination of risk factors for injury in female professional basketball players is worthwhile. Objective: To examine rates of ankle sprains, associated time missed from participation, and risk factors for injury during 2 consecutive seasons. Design: Prospective cohort study. Setting: Eighteen professional basketball facilities. Patients or Other Participants: We observed 204 players from 18 female professional basketball teams for 2 consecutive seasons during a 2-year period. Main Outcome Measure(s): Using questionnaires, we recorded the incidence of ankle sprains, participation time missed, and mechanisms of injury in games and practice sessions. Potential risk factors, such as age, body mass, height, training experience, and history of ankle sprain, were examined using multivariate logistic regression. Results: Fifty of the 204 participants sustained ankle injuries; injuries included 32 ankle sprains, which translated to an ankle sprain rate of 1.12 per 1000 hours of exposure to injury. The 32 players missed 224.4 training and game sessions and an average of 7.01 sessions per injury. Most injuries occurred in the key area of the basketball court and were the result of contact. Injury rates during games were higher than injury rates during practice sessions. Centers, followed by guards and forwards, had the highest rate of injury. Players who did not wear an external ankle support had an odds ratio of 2.481 for sustaining an ankle sprain. Conclusions: Female professional basketball athletes who did not wear an external ankle support, who played in the key area, or who functioned as centers had a higher risk for ankle sprain than did other players. PMID:18059995

  20. Carbon Fibers Conductivity Studies

    NASA Technical Reports Server (NTRS)

    Yang, C. Y.; Butkus, A. M.

    1980-01-01

    In an attempt to understand the process of electrical conduction in polyacrylonitrile (PAN)-based carbon fibers, calculations were carried out on cluster models of the fiber consisting of carbon, nitrogen, and hydrogen atoms using the modified intermediate neglect of differential overlap (MINDO) molecular orbital (MO) method. The models were developed based on the assumption that PAN carbon fibers obtained with heat treatment temperatures (HTT) below 1000 C retain nitrogen in a graphite-like lattice. For clusters modeling an edge nitrogen site, analysis of the occupied MO's indicated an electron distribution similar to that of graphite. A similar analysis for the somewhat less stable interior nitrogen site revealed a partially localized II electron distribution around the nitrogen atom. The differences in bonding trends and structural stability between edge and interior nitrogen clusters led to a two-step process proposed for nitrogen evolution with increasing HTT.

  1. Acinetobacter Infections among Adult Patients in Qatar: A 2-Year Hospital-Based Study

    PubMed Central

    Al Samawi, Musaed Saad; Khan, Fahmi Yousef; Eldeeb, Yasser; Almaslamani, Muna; Alkhal, Abdullatif; Alsoub, Hussam; Ghadban, Wissam; Howady, Faraj; Hashim, Samar

    2016-01-01

    This retrospective study was conducted at Hamad General Hospital, Qatar, to describe the demographic data, clinical features underlying diseases, antimicrobial susceptibility, and outcome of A. baumannii infection. It involved all adult patients 15 years of age or older who were managed at Hamad General Hospital for A. baumannii infection from January 1, 2012, to December 31, 2013. We identified a total of 239 patients with A. baumannii infection, of which 182 (76.2%) were males. The mean age was 49.10 ± 19.57 years. The majority of the episodes (25.1%) occurred in elderly patients (≥65 years) and the most commonly identified site of A. baumannii infection was the respiratory tract, 117 (48.9%). Most episodes of infection, 231 (96.7%), were hospital-acquired and high rate of nosocomial infections occurred in the medical intensive care unit, 66 (28.6%). All patients had underlying medical conditions. Maximum resistance was seen to cefotaxime, 147 (58.3%), and minimum resistance was seen to colistin, 2 (1.4%). Of the 239 isolates, 102 (42.7%) were susceptible and 137 (57.3%) were multidrug-resistant. The in-hospital mortality in our study was 31%. Male gender, multidrug resistance, and septic shock were found to be independent mortality predictors. PMID:27433169

  2. Acinetobacter Infections among Adult Patients in Qatar: A 2-Year Hospital-Based Study.

    PubMed

    Al Samawi, Musaed Saad; Khan, Fahmi Yousef; Eldeeb, Yasser; Almaslamani, Muna; Alkhal, Abdullatif; Alsoub, Hussam; Ghadban, Wissam; Howady, Faraj; Hashim, Samar

    2016-01-01

    This retrospective study was conducted at Hamad General Hospital, Qatar, to describe the demographic data, clinical features underlying diseases, antimicrobial susceptibility, and outcome of A. baumannii infection. It involved all adult patients 15 years of age or older who were managed at Hamad General Hospital for A. baumannii infection from January 1, 2012, to December 31, 2013. We identified a total of 239 patients with A. baumannii infection, of which 182 (76.2%) were males. The mean age was 49.10 ± 19.57 years. The majority of the episodes (25.1%) occurred in elderly patients (≥65 years) and the most commonly identified site of A. baumannii infection was the respiratory tract, 117 (48.9%). Most episodes of infection, 231 (96.7%), were hospital-acquired and high rate of nosocomial infections occurred in the medical intensive care unit, 66 (28.6%). All patients had underlying medical conditions. Maximum resistance was seen to cefotaxime, 147 (58.3%), and minimum resistance was seen to colistin, 2 (1.4%). Of the 239 isolates, 102 (42.7%) were susceptible and 137 (57.3%) were multidrug-resistant. The in-hospital mortality in our study was 31%. Male gender, multidrug resistance, and septic shock were found to be independent mortality predictors. PMID:27433169

  3. Prescription Disposal Practices: A 2-Year Ecological Study of Drug Drop Box Donations in Appalachia

    PubMed Central

    Hagemeier, Nicholas; Brooks, Billy; Alamian, Arsham

    2015-01-01

    Objectives. We quantified controlled substance donations via permanent drug donation boxes over 2 years in a region with high prescription abuse, assessing medication characteristics, time between dispensing and donation, and weight of medications donated per capita. Methods. In partnership with Drug Enforcement Administration and local law enforcement, we analyzed permanent drug donation box collections in 8 Northeast Tennessee locations from June 2012 to April 2014. We recorded controlled substance dosage units along with the product dispensing date. Results. We collected 4841 pounds of pharmaceutical waste, 4.9% (238.5 pounds) of which were controlled substances, totaling 106 464 controlled substance doses. Analysis of dispensing dates for controlled substances indicated a median of 34 months lapsed from dispensing to donation (range = 1–484 months). The mean controlled substance donation rate was 1.39 pounds per 1000 residents. Communities with fewer than 10 000 residents had a statistically higher controlled substance donation rate (P = .002) compared with communities with 10 000 or more residents. Conclusions. Permanent drug donation boxes can be an effective mechanism to remove controlled substances from community settings. Rural and urban community residents should be provided convenient and timely access to drug disposal options. PMID:26180956

  4. Long-Term Outcomes of a Web-Based Diabetes Prevention Program: 2-Year Results of a Single-Arm Longitudinal Study

    PubMed Central

    Jiang, Luohua; Peters, Anne L

    2015-01-01

    Background Digital therapeutics are evidence-based behavioral treatments delivered online that can increase accessibility and effectiveness of health care. However, few studies have examined long-term clinical outcomes of digital therapeutics. Objective The objective of this study was to conduct a 2-year follow-up on participants in the Internet-based Prevent diabetes prevention program pilot study, specifically examining the effects on body weight and A1c, which are risk factors for diabetes development. Methods A quasi-experimental research design was used, including a single-arm pre- and post-intervention assessment of outcomes. Participants underwent a 16-week weight loss intervention and an ongoing weight maintenance intervention. As part of the program, participants received a wireless scale, which was used to collect body weight data on an ongoing basis. Participants also received A1c test kits at baseline, 0.5 year, 1 year, and 2-year time points. Results Participants previously diagnosed with prediabetes (n=220) were originally enrolled in the pilot study. A subset of participants (n=187) met Centers for Disease Control and Prevention (CDC) criteria for starting the program (starters), and a further subset (n=155) met CDC criteria for completing the program (completers) and were both included in analyses. Program starters lost an average of 4.7% (SD 0.4) of baseline body weight after 1 year and 4.2% (SD 0.8) after 2 years, and reduced A1c by mean 0.38% (SD 0.07) after 1 year and 0.43% (SD 0.08) after 2 years. Program completers lost mean 4.9% (SD 0.5) of baseline body weight after 1 year and 4.3% (SD 0.8) after 2 years, and reduced A1c by 0.40% (SD 0.07) after 1 year and 0.46% (SD 0.08) after 2 years. For both groups, neither 2-year weight loss nor A1c results were significantly different from 1-year results. Conclusions Users of the Prevent program experienced significant reductions in body weight and A1c that are maintained after 2 years. Contrary to the

  5. Stability and Change among High-Functioning Children with Pervasive Developmental Disorders: A 2-Year Outcome Study.

    ERIC Educational Resources Information Center

    Starr, Elizabeth; Szatmari, Peter; Bryson, Susan; Zwaigenbaum, Lonnie

    2003-01-01

    This study compared the 2-year outcomes of 68 children diagnosed with autism or Asperger syndrome at age 6-8 years in terms of symptoms from the Autism Diagnostic Interview. Significant differences were seen in the domains of social interaction, communication, and repetitive activities, with the Asperger group demonstrating fewer and/or less…

  6. Sluggish Cognitive Tempo and ADHD Inattention as Predictors of Externalizing, Internalizing, and Impairment Domains: A 2-Year Longitudinal Study.

    PubMed

    Bernad, Maria del Mar; Servera, Mateu; Becker, Stephen P; Burns, G Leonard

    2016-05-01

    Although sluggish cognitive tempo (SCT) is distinct from attention-deficit/hyperactivity disorder inattention (ADHD-IN), few studies have examined whether SCT longitudinally predicts other symptom or impairment dimensions. This study used 4 sources (mothers, fathers, primary teachers, and secondary teachers) and 3 occasions of measurement (first, second, and third grades) with 758 first grade (55 % boys), 718 second grade (54 % boys), and 585 third grade (53 % boys) children from Spain to determine SCT's and ADHD-IN's unique longitudinal relationships with psychopathology, academic impairment, and social impairment over the 1- and 2-year intervals (i.e., first to third grade, second to third grade). For 1- and 2-year intervals using both mothers' and fathers' ratings, higher levels of SCT uniquely predicted higher levels of anxiety, depression, academic impairment, and social impairment whereas higher levels of ADHD-IN uniquely predicted higher levels of ADHD-HI, ODD, and academic impairment. For 1- and 2-year intervals across different primary and secondary teachers (i.e., first/second and third grade ratings were provided by different teachers), higher scores on ADHD-IN uniquely predicted poorer outcomes across domains whereas higher scores on SCT uniquely predicted lower levels of ADHD-HI and ODD for both intervals in addition to higher levels of depression (for primary teachers only), academic impairment (for 1-year interval only), and peer rejection (2-year interval only for primary teachers). Overall, SCT was significantly associated with important outcomes independent of ADHD-IN over 1- and 2-year intervals and across four different raters. This study provides further evidence for distinguishing between SCT and ADHD-IN in home and school settings. PMID:26278273

  7. Treatment Compliance of Adolescents after Attempted Suicide: A 2-Year Follow-Up Study

    ERIC Educational Resources Information Center

    Burns, Craig D.; Cortell, Ranon; Wagner, Barry M.

    2008-01-01

    The study investigates compliance with mental health treatments among suicidal adolescents. Results show that child psychopathology and parental attitudes toward treatment plays an important part in increasing compliance with mental health treatment for adolescent suicide attempters.

  8. Diagnosis of Autism Spectrum Disorders in 2-Year-Olds: A Study of Community Practice

    ERIC Educational Resources Information Center

    Corsello, Christina M.; Akshoomoff, Natacha; Stahmer, Aubyn C.

    2013-01-01

    Background: Longitudinal research studies have demonstrated that experienced clinicians using standardized assessment measures can make a reliable diagnosis of autism spectrum disorders (ASDs) in children under age 3. Limited data are available regarding the sensitivity and specificity of these measures in community settings. The aims of this…

  9. Development of Orthographic Knowledge in German-Speaking Children: A 2-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Ise, Elena; Arnoldi, Carolin Judith; Schulte-Körne, Gerd

    2014-01-01

    There is growing evidence that children develop orthographic knowledge from the very beginning of literacy acquisition. This study investigated the development of German-speaking children's orthographic knowledge with a nonword choice task. One nonword in each pair contained a frequent consonant doublet ("zommul") and the other…

  10. Pubertal Timing and Substance Use in Middle Adolescence: A 2-Year Follow-Up Study

    ERIC Educational Resources Information Center

    Kaltiala-Heino, Riittakerttu; Koivisto, Anna-Maija; Marttunen, Mauri; Frojd, Sari

    2011-01-01

    Earlier research has associated early puberty with emotional and behavioral symptoms particularly among girls, while among boys, findings have been contradictory as to whether risks are associated with early or late pubertal timing. We studied the association between pubertal timing and substance use behaviors in middle adolescence in a 2-year…

  11. The Development of Falling Intonation in Young Children with Cochlear Implants: A 2-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Snow, David P.; Ertmer, David J.

    2013-01-01

    This article describes the development of intonation in 12 cochlear implant (CI) recipients. In a previously reported study of the first year of CI use, children who were implanted late (after 24 months) acquired intonation more rapidly than the younger participants. The older children's advantage is plausibly owing to their greater maturity.…

  12. A 2 year longitudinal study of Cryptosporidium species and genotypes in dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this, the first long term longitudinal study of cryptosporidiosis in cattle, 30 pure-bred Holstein female cattle on a dairy farm in Maryland were examined consecutively at weekly, biweekly, or monthly intervals from 1 week to 24 months of age for the presence of Cryptosporidium oocysts. Feces wer...

  13. Predicting Expressive Vocabulary Acquisition in Children with Intellectual Disabilities: A 2-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Vandereet, Joke; Maes, Bea; Lembrechts, Dirk; Zink, Inge

    2010-01-01

    Purpose: This study's objectives were to describe expressive vocabulary acquisition in children with intellectual disabilities (ID) and to examine specific pre- and early linguistic behaviors used to request and comment, chronological age, cognitive skills, and vocabulary comprehension as predictors of expressive vocabulary. Method: This study…

  14. Re-defining one's occupational self 2 years after breast cancer: a case study.

    PubMed

    Newman, Robin M

    2013-01-01

    Margaret*, a 56 year-old Caucasian Stage III breast cancer survivor, participated in a 5 week occupational therapy pilot program, called Take Action. This program was designed for breast cancer survivors who self-reported changes in cognitive function following completion of chemotherapy. The goals of the program were to improve participants' knowledge and use of strategies to enhance occupational performance and to improve satisfaction and performance of meaningful daily activities or occupations. Through a client-centered and evidence-based approach, this case study highlights the importance of incorporating the survivors' sense of self into an occupation-based intervention. Occupational therapists play an important role in facilitating exploration of sense of self in the survivorship phase of care to support occupational performance in self care, productivity, work, leisure and social participation. This case study highlights the important work of redefining oneself in the survivorship phase of care. (*denotes name change). PMID:24004739

  15. Involvement in bullying and suicidal ideation in middle adolescence: a 2-year follow-up study.

    PubMed

    Heikkilä, Hanna-Kaisa; Väänänen, Juha; Helminen, Mika; Fröjd, Sari; Marttunen, Mauri; Kaltiala-Heino, Riittakerttu

    2013-02-01

    The objective of the study was to ascertain whether involvement in bullying increases the risk for subsequent suicidal ideation. A total of 2,070 Finnish girls and boys aged 15 were surveyed in the ninth grade (age 15) in schools, and followed up 2 years later in the Adolescent Mental Health Cohort Study. Involvement in bullying was elicited at age 15 by two questions focusing on being a bully and being a victim of bullying. Suicidal ideation was elicited by one item of the short Beck Depression Inventory at age 17. Baseline depressive symptoms and externalizing symptoms, age and sex were controlled for. Statistical analyses were carried out using cross-tabulations with Chi-square/Fisher's exact test and logistic regression. Suicidal ideation at age 17 was 3-4 times more prevalent among those who had been involved in bullying at age 15 than among those not involved. Suicidal ideation at age 17 was most prevalent among former victims of bullying. Being a victim of bullying at age 15 continued to predict subsequent suicidal ideation when depressive and externalizing symptoms were controlled for. Being a bully at age 15 also persisted as borderline significantly predictive of suicidal ideation when baseline symptoms were controlled for. Findings indicate adolescent victims and perpetrators of bullying alike are at long-term risk for suicidal ideation. PMID:23053774

  16. Prehospital versus Emergency Room Intubation of Trauma Patients in Qatar: A-2-year Observational Study

    PubMed Central

    Al-Thani, Hassan; El-Menyar, Ayman; Latifi, Rifat

    2014-01-01

    Background: The impact of prehospital intubation (PHI) in improving outcome of trauma patients has not been adequately evaluated in the developing countries. Aims: The present study analyzed the outcome of PHI versus emergency room intubation (ERI) among trauma patients in Qatar. Materials and Methods: Data were retrospectively reviewed for all intubated trauma patients between 2010 and 2011. Patients were classified according to location of intubation (PHI: Group-1 versus ERI: Group-2). Data were analyzed and compared. Results: Out of 570 intubated patients; 482 patients (239 in group-1 and 243 in group-2) met the inclusion criteria with a mean age of 32 ΁ 14.6 years Head injury (P = 0.003) and multiple trauma (P = 0.004) were more prevalent in group-1, whereas solid organ injury predominated in group-2 (P = 0.02). Group-1 had significantly higher mean injury severity scoring (ISS), lower Glasgow coma scale (GCS), greater head abbreviated injury score and longer activation, response, scene and total emergency medical services times. The mortality was higher in group-1 (53% vs. 18.5%; P = 0.001). Multivariate analysis showed that GCS [odds ratio (OR) 0.78, P = 0.005) and ISS (OR 1.12, P = 0.001) were independent predictors of mortality. Conclusions: PHI is associated with high mortality when compared with ERI. However, selection bias cannot be ruled out and therefore, PHI needs further critical assessment in Qatar. PMID:24678471

  17. A longitudinal study of cryptosporidiosis in dairy cattle from birth to 2 years of age.

    PubMed

    Santín, Mónica; Trout, James M; Fayer, Ronald

    2008-08-01

    Fecal specimens were collected from 30 calves from birth to 24 months of age at a dairy farm in Maryland to determine the prevalence and age distribution of Cryptosporidium species/genotypes. After centrifugation to remove debris and concentrate oocysts, specimens were examined by immunofluorescence microscopy and polymerase chain reaction (PCR). Fragments of the SSU-rDNA gene amplified by PCR were purified and PCR products were sequenced. All 30 calves shed Cryptosporidium oocysts at some time during the 24 months of the study. Of 990 specimens, 190 were Cryptosporidium-positive (19.2%). The highest prevalence of infection was at 2 weeks of age when 29 of the 30 calves were excreting oocysts. Prevalence was higher in pre-weaned calves (1-8 weeks of age) (45.8%) than in post-weaned calves (3-12 months of age) (18.5%) and heifers (12-24 months of age) (2.2%). Sequence data for 190 PCR-positive specimens identified: C. parvum, C. bovis, the Cryptosporidium deer-like genotype and C. andersoni, with cumulative prevalences of 100, 80, 60, and 3.3%, respectively. C. parvum constituted 97% of infections in pre-weaned calves but only 4% and 0% of infections in post-weaned calves and heifers, respectively. All C. parvum GP60 nucleotide sequences were subtype IIaA15G2R1. PMID:18565677

  18. Frequency and nature of spontaneous age-related eye lesions observed in a 2-year inhalation toxicity study in rats.

    PubMed

    Wegener, A; Kaegler, M; Stinn, W

    2002-01-01

    A group of 160 Wistar rats (both sexes) from a larger chronic inhalation toxicity study was monitored at baseline and after 1 and 2 years with a photo-slitlamp microscope and a direct ophthalmoscope to record spontaneous age-related eye lesions and treatment-related eye lesions over a period of 24 months. A second group from the same study was monitored at the start and after 5 months of a 6-month posttreatment period immediately following the inhalation period. Rats were nose-only exposed for 6 h/day, 7 days/week, for 2 years to low (3 microg/l) or high (10 microg/l) total particulate matter concentrations of room-aged cigarette sidestream smoke (RASS) or diesel engine exhaust (DEE). Control animals were exposed to filtered fresh air. All ophthalmological examinations were performed in mydriasis, and relevant observations were documented on color slide film. At baseline, all animals with eye lesions were excluded from the study. After 1 year, only minor lesions were found: retrolental opacities (14%) and a few cases of corneal dryness with reddish lid margins. After 2 years, 23% of the animals had unilateral or bilateral retrolental opacities, but the most frequent eye lesions were posterior subcapsular cataracts (PSC, 32%). Water clefts and spokes were found in 11% of the lenses and mature cataracts in 6%. All other eye lesions observed were much less frequent. There were a few cases of glaucoma, corneal dryness and stromal neovascularization. The frequency and type of lesion in animals monitored from the start of the posttreatment period was comparable to what was seen after 2 years. Toward the end of this period the frequency of mature cataracts went up to 9% and that of (secondary) glaucomas to 5%. None of the eye lesions observed showed any association in frequency or severity of expression to the treatment, either RASS or DEE, or to the sex of the animals. In comparison to the (limited) literature data available, far fewer corneal lesions were found in this

  19. Conducting Simulation Studies in Psychometrics

    ERIC Educational Resources Information Center

    Feinberg, Richard A.; Rubright, Jonathan D.

    2016-01-01

    Simulation studies are fundamental to psychometric discourse and play a crucial role in operational and academic research. Yet, resources for psychometricians interested in conducting simulations are scarce. This Instructional Topics in Educational Measurement Series (ITEMS) module is meant to address this deficiency by providing a comprehensive…

  20. Prognostic value of low and moderately elevated C-reactive protein in acute coronary syndrome: A 2-year follow-up study

    PubMed Central

    Lukin, Ajvor; Novak, Katarina; Polić, Stojan; Puljak, Livia

    2013-01-01

    Background The main goal of this study was to improve diagnostic and predictive value of low and moderately elevated C-reactive protein (CRP) in patients with acute coronary syndrome (ACS), related to noninvasive clinical parameters, in order to improve and prolong patient life with low or no additional costs. Material/Methods A prospective, open clinical study was conducted at the University Hospital Split, Croatia with 112 patients with ACS and low or moderately elevated CRP (<3.0 mg/L). After diagnosing ACS, data on physical activity, alcohol consumption, and functional status were recorded. Anthropometric measurements were made. Blood and urine samples were taken for analyses. Electrocardiographic, ergometric, and echocardiographic testing was performed. A total of 72 parameters were monitored at the time of hospital admission in ACS patients to analyze which ones could predict disease outcome at the end of follow-up in patients with low or moderately elevated CRP. Patients were followed up for 2 years. Results The variables that were predictive of major adverse cardiac events (MACE) within 2 years of ACS hospitalization were hemoglobin, fibrinogen, antithrombin III, cholesterol levels, brain natriuretic peptide, and microalbuminuria. ACS patients with CRP <3.0 mg/L had significantly higher risk of developing MACE within 2 years if ≥50% of the 8 key parameters were outside the reference values. Conclusions Major adverse cardiac events can be predicted in patients with acute coronary syndrome whose CRP values are low or moderately elevated. PMID:24051868

  1. Progression of fibromyalgia: results from a 2-year observational fibromyalgia and chronic pain study in the US

    PubMed Central

    Adams, Edgar H; McElroy, Heather J; Udall, Margarita; Masters, Elizabeth T; Mann, Rachael M; Schaefer, Caroline P; Cappelleri, Joseph C; Clair, Andrew G; Hopps, Markay; Daniel, Shoshana R; Mease, Philip; Silverman, Stuart L; Staud, Roland

    2016-01-01

    Background A previous fibromyalgia (FM) research reports that 20%–47% of diagnosed patients may not meet the study definition of FM 1–2 years after diagnosis. The aim of this study was to gain a better understanding of the progression of FM in a geographically diverse cohort over a 2-year time period. Methods This cohort study followed 226 subjects recruited online to assess FM and chronic widespread pain (CWP) diagnosis stability over time. At enrollment (baseline), subjects provided informed consent, completed an online questionnaire consisting of the London Fibromyalgia Epidemiology Study Screening Questionnaire to screen for CWP (bilateral pain above/below waist lasting ≥1 week in the past 3 months), visited a site for physician evaluation for FM, and completed a questionnaire with validated patient-reported outcome instruments. Subjects were classified into mutually exclusive groups: FM+CWP+ (screened positive for CWP and received physician diagnosis of FM), FM−CWP+ (screened positive for CWP but did not receive physician diagnosis of FM), and FM−CWP− (screened negative for CWP). Approximately 2 years later (follow-up), subjects were reassessed at the same study site and completed a questionnaire with the same patient-reported outcomes. Results Seventy-six FM+CWP+ subjects completed assessments at both time points; 56 (73.7%) met the FM study definition at follow-up. Twenty subjects no longer met the FM study definition (eleven became FM−CWP− and nine became FM−CWP+). Ten subjects (two from FM−CWP− and eight from FM−CWP+) transitioned into the FM+CWP+ group at follow-up; they reported more tender points and pain interference with sleep and worse physical function at baseline compared with subjects who did not transition to FM+CWP+. Most (76.7%) of the subjects who transitioned into/out of FM+CWP+ experienced changes in CWP, number of positive tender points, or both. Conclusion The results suggest that some FM+CWP+ patients experience

  2. Bioconversion study conducted by JPL

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J.

    1978-01-01

    The Jet Propulsion Laboratory (JPL) of Caltech conducted a study of bioconversion as a means of identifying the role of biomass for meeting the national energy fuel and chemical requirements and the role and means for JPL-Caltech involvement in bioconversion. The bioconversion study included the following categories; biomass sources, chemicals from biomass, thermochemical conversion of biomass to fuels, biological conversion of biomass to fuels and chemicals, and basic bioconversion sciences. A detailed review is included of the bioconversion fields cited with specific conclusions and recommendations given for future research and development and overall biomass system engineering and economic studies.

  3. Quality of life of breast cancer patients medicated with anti-estrogens, 2 years after acupuncture treatment: a qualitative study

    PubMed Central

    Hervik, Jill; Mjåland, Odd

    2010-01-01

    Objective The aim of this study was to examine the quality of life of breast cancer patients medicated with estrogen antagonists, 2 years after having acupuncture treatment for hot flashes. Methods and materials Our sample was taken from women who had recently participated in a randomized controlled trial investigating the effects of acupuncture on hot flashes, a side effect of estrogen-antagonist treatment. Forty-one women from the true acupuncture treatment group and 41 women from the control group (sham acupuncture), who had 2 years previously received a course of 15 acupuncture treatments over a period of 10 weeks, were asked to answer an open question. The question, “Would you like to share your thoughts and experiences related to your breast cancer diagnosis, treatments or anything else?” was by being open, broad, and nonspecific, intended to stimulate subjective information, which was not included in the original, or future quantitative studies. Qualitative data were analyzed using systematic text condensation. Results Most women were troubled by two or more side effects due to anti-estrogen medication, negatively affecting their life quality. Symptoms included hot flashes, sleep problems, muscle and joint pain, arm edema, fatigue, weight gain, depression, and lack of sexual desire. Women previously treated with sham acupuncture complained that hot flashes were still problematic, whilst those previously treated with traditional Chinese acupuncture found them less of a problem and generally had a more positive outlook on life. These results compare favorably with the findings from our original study that measured quantitatively health related quality of life. Conclusion Side effects due to anti-estrogen treatment seriously affect the quality of life of breast cancer operated patients. Patients who had previously been treated with traditional Chinese acupuncture complained less of hot flashes, and had a more positive outlook on life, than women who had

  4. Nerve conduction and electromyography studies.

    PubMed

    Kane, N M; Oware, A

    2012-07-01

    Nerve conduction studies (NCS) and electromyography (EMG), often shortened to 'EMGs', are a useful adjunct to clinical examination of the peripheral nervous system and striated skeletal muscle. NCS provide an efficient and rapid method of quantifying nerve conduction velocity (CV) and the amplitude of both sensory nerve action potentials (SNAPs) and compound motor action potentials (cMAPs). The CV reflects speed of propagation of action potentials, by saltatory conduction, along large myelinated axons in a peripheral nerve. The amplitude of SNAPs is in part determined by the number of axons in a sensory nerve, whilst amplitude of cMAPs reflects integrated function of the motor axons, neuromuscular junction and striated muscle. Repetitive nerve stimulation (RNS) can identify defects of neuromuscular junction (NMJ) transmission, pre- or post-synaptic. Needle EMG examination can detect myopathic changes in muscle and signs of denervation. Combinations of these procedures can establish if motor and/or sensory nerve cell bodies or peripheral nerves are damaged (e.g. motor neuronopathy, sensory ganglionopathy or neuropathy), and also indicate if the primary target is the axon or the myelin sheath (i.e. axonal or demyelinating neuropathies). The distribution of nerve damage can be determined as either generalised, multifocal (mononeuropathy multiplex) or focal. The latter often due to compression at the common entrapment sites (such as the carpal tunnel, Guyon's canal, cubital tunnel, radial groove, fibular head and tarsal tunnel, to name but a few of the reported hundred or so 'entrapment neuropathies'). PMID:22614870

  5. Disordered eating behaviors and body image in a longitudinal pilot study of adolescent girls: what happens 2 years later?

    PubMed

    Espinoza, Paola; Penelo, Eva; Raich, Rosa M

    2010-01-01

    We assessed the prospective association of risk factors for eating and body image disturbances after a 2-year follow-up in a community sample of Spanish adolescent girls. The participants included 128 Spanish girls aged 12-14, who took part in a 28-month prospective study. Aspects assessed were eating attitudes (Eating Attitudes Test), influence of the body shape model (questionnaire on influences of the aesthetic body shape model), extreme weight-control behaviors (Eating Disorder Examination-Questionnaire), body image (Body Image Questionnaire) and Body Mass Index (BMI). BMI, extreme weight-control behaviors and body image problems emerged as potential predictors of an increase in eating disturbances. An increased influence of the thinness model was significantly associated with reduced body satisfaction and body image problems. Preventive programs are needed to contribute reducing the impact of sociocultural influences with regard to thinness, the use of extreme weight-control behaviors and overweight in adolescents. PMID:19815475

  6. NOAA's hydrolab conducts reef studies

    NASA Astrophysics Data System (ADS)

    This summer, scuba-diving scientists operating from Hydrolab, NOAA's undersea laboratory, are carrying out four experiments aimed at producing better management of coral reefs and their fishery resources. Hydrolab is located at a depth of 50 feet, near the mouth of the Salt River, off St. Croix, U.S. Virgin Islands. The lab houses four scientists for up to 2 weeks at a time, permitting them to swim out into the water to conduct research. The projects make use of both the natural coral reef near Hydrolab and the nearby artificial reef constructed for comparison studies.

  7. The improving outcomes in intermittent exotropia study: outcomes at 2 years after diagnosis in an observational cohort

    PubMed Central

    2012-01-01

    Background The purpose of this study was to investigate current patterns of management and outcomes of intermittent distance exotropia [X(T)] in the UK. Methods This was an observational cohort study which recruited 460 children aged < 12 years with previously untreated X(T). Eligible subjects were enrolled from 26 UK hospital ophthalmology clinics between May 2005 and December 2006. Over a 2-year period of follow-up, clinical data were prospectively recorded at standard intervals from enrolment. Data collected included angle, near stereoacuity, visual acuity, control of X(T) measured with the Newcastle Control Score (NCS), and treatment. The main outcome measures were change in clinical outcomes (angle, stereoacuity, visual acuity and NCS) in treated and untreated X(T), 2 years from enrolment (or, where applicable, 6 months after surgery). Change over time was tested using the chi-square test for categorical, Wilcoxon test for non-parametric and paired-samples t-test for parametric data. Results At follow-up, data were available for 371 children (81% of the original cohort). Of these: 53% (195) had no treatment; 17% (63) had treatment for reduced visual acuity only (pure refractive error and amblyopia); 13% (50) had non surgical treatment for control (spectacle lenses, occlusion, prisms, exercises) and 17% (63) had surgery. Only 0.5% (2/371) children developed constant exotropia. The surgically treated group was the only group with clinically significant improvements in angle or NCS. However, 8% (5) of those treated surgically required second procedures for overcorrection within 6 months of the initial procedure and at 6-month follow-up 21% (13) were overcorrected. Conclusions Many children in the UK with X(T) receive active monitoring only. Deterioration to constant exotropia, with or without treatment, is rare. Surgery appears effective in improving angle of X(T) and NCS, but rates of overcorrection are high. PMID:22257496

  8. Prospective study of cognitive function in children receiving whole-brain radiotherapy and chemotherapy: 2-year results

    SciTech Connect

    Packer, R.J.; Sutton, L.N.; Atkins, T.E.; Radcliffe, J.; Bunin, G.R.; D'Angio, G.; Siegel, K.R.; Schut, L. )

    1989-05-01

    As survival rates have risen for children with malignant primary brain tumors, so has the concern that many survivors have significant permanent cognitive deficits. Cranial irradiation (CRT) has been implicated as the major cause for cognitive dysfunction. To clarify the etiology, incidence, and severity of intellectual compromise in children with brain tumors after CRT, a prospective study was undertaken comparing the neuropsychological outcome in 18 consecutive children with malignant brain tumors treated with CRT to outcome in 14 children harboring brain tumors in similar sites in the nervous system who had not received CRT. Children with cortical or subcortical brain tumors were not eligible for study. Neuropsychological testing was performed after surgery prior to radiotherapy, after radiotherapy, and at 1- and 2-year intervals thereafter. Children who had received CRT had a mean full-scale intelligence quotient (FSIQ) of 105 at diagnosis which fell to 91 by Year 2. Similar declines were noted in their performance intelligence quotient (IQ) and verbal IQ. After CRT, patients demonstrated a statistically significant decline from baseline in FSIQ (p less than 0.02) and verbal IQ (p less than 0.04). Children who had not received CRT did not demonstrate a fall in any cognitive parameter over time. The decline between baseline testing and testing performed at Year 2 in patients who had CRT was inversely correlated with age (p less than 0.02), as younger children demonstrated the greatest loss of intelligence. Children less than 7 years of age at diagnosis had a mean decline in FSIQ of 25 points 2 years posttreatment. No other clinical parameter correlated with the overall IQ or decline in IQ. After CRT, children demonstrated a wide range of dysfunction including deficits in fine motor, visual-motor, and visual-spatial skills and memory difficulties.

  9. Use of Ergonomic Measures Related to Musculoskeletal Complaints among Construction Workers: A 2-year Follow-up Study

    PubMed Central

    Boschman, Julitta S.; Frings-Dresen, Monique H.W.; van der Molen, Henk F.

    2015-01-01

    Background The physical work demands of construction work can be reduced using ergonomic measures. The aim of this study was to evaluate the use of ergonomic measures related to musculoskeletal disorders (MSDs) among construction workers. Methods A questionnaire was sent at baseline and 2 years later to 1,130 construction workers. We established (1) the proportion of workers reporting an increase in their use of ergonomic measures, (2) the proportion of workers reporting a decrease in MSDs, (3) the relative risk for an increase in the use of ergonomic measures and a decrease in MSDs, and (4) workers' knowledge and opinions about the use of ergonomic measures. Results At follow-up, response rate was 63% (713/1,130). The proportion of workers using ergonomic measures for vertical transport increased (34%, 144/419, p < 0.01); for measures regarding horizontal transport and the positioning of materials, no change was reported. The proportion of workers reporting shoulder complaints decreased (28%, 176/638, p = 0.02). A relationship between the use of ergonomic measures and MSDs was not found; 83% (581/704) of the workers indicated having sufficient knowledge about ergonomic measures. Lightening the physical load was reported to be the main reason for using them. Conclusion Only the use of ergonomic measures for vertical transport increased over a 2-year period. No relationship between the use of ergonomic measures and MSDs was found. Strategies aimed at improving the availability of ergonomic equipment complemented with individualized advice and training in using them might be the required next steps to increase the use of ergonomic measures. PMID:26106507

  10. Lumbar total disc replacement using ProDisc II: a prospective study with a 2-year minimum follow-up.

    PubMed

    Chung, Sung Soo; Lee, Chong Suh; Kang, Chang Seok

    2006-08-01

    A lumbar total disc replacement (TDR) is believed to be a promising substitute in the surgical treatment for lumbar degenerative disc disease. The purpose of this study is to report the clinical and radiographic outcomes of 36 consecutive patients who underwent lumbar TDR using ProDisc II, and the factors associated with a better clinical outcome after a 2-year minimum follow-up. At the time of the latest follow-up, the success rate was 94% of 36 patients according to the criteria of the US Food and Drug Administration. Of the 10 patients unable to work preoperatively, 7 patients returned to work. Moreover, mean score on the visual analog scale for low back and leg pain improved significantly from 7.5 and 4.7 to 3.0 and 1.2, respectively (P<0.001). In addition, mean Oswestry disability index scores improved significantly from 69.2 to 21.0 (P<0.001). Mean disc height at the operative level increased significantly from 9.0 to 17.6 mm, and mean range of motion increased significantly from 9.7 to 12.7 degrees (P<0.01). Statistical analysis showed that the factors associated with a better clinical outcome were single level, and a higher postoperative segmental ROM at the operative level. At a minimum follow-up of 2 years, the lumbar TDR using ProDisc II showed excellent clinical and radiographic outcomes without any significant complication. However, future efforts need to be directed toward the evaluation of a larger number of patients with longer follow-up. PMID:16891976

  11. Effect of Workplace Noise on Hearing Ability in Tile and Ceramic Industry Workers in Iran: A 2-Year Follow-Up Study

    PubMed Central

    Mirmohammadi, Seyyed Jalil; Mehrparvar, Amir Houshang; Mollasadeghi, Abolfazl

    2013-01-01

    Introduction. Noise as a common physical hazard may lead to noise-induced hearing loss, an irreversible but preventable disorder. Annual audiometric evaluations help detect changes in hearing status before clinically significant hearing loss develops. This study was designed to track hearing threshold changes during 2-year follow-up among tile and ceramic workers. Methods. This follow-up study was conducted on 555 workers (totally 1110 ears). Subjects were divided into four groups according to the level of noise exposure. Hearing threshold in conventional audiometric frequencies was measured and standard threshold shift was calculated for each ear. Results. Hearing threshold was increased during 2 years of follow-up. Increased hearing threshold was most frequently observed at 4000, 6000, and 3000 Hz. Standard threshold shift was observed in 13 (2.34%), 49 (8.83%), 22 (3.96%), and 63 (11.35%) subjects in the first and second years of follow-up in the right and left ears, respectively. Conclusions. This study has documented a high incidence of noise-induced hearing loss in tile and ceramic workers that would put stress on the importance of using hearing protection devices. PMID:24453922

  12. Work–family conflict and health in Swedish working women and men: a 2-year prospective analysis (the SLOSH study)

    PubMed Central

    Baltzer, Maria; Magnusson Hanson, Linda L.; Westerlund, Hugo

    2013-01-01

    Background: Research has suggested that gender is related to perceptions of work–family conflict (WFC) and an underlying assumption is that interference of paid work with family life will burden women more than men. There is, however, mixed evidence as to whether men and women report different levels of WFC. Even less studies investigate gender differences in health outcomes of WFC. Also the number of longitudinal studies in this field is low. Methods: Based on the Swedish Longitudinal Occupational Survey of Health, we prospectively examined the effects of WFC on three different health measures representing a wide spectrum off ill health (i.e. self-rated health, emotional exhaustion and problem drinking). Logistic regression analyses were used to analyse multivariate associations between WFC in 2008 and health 2 years later. Results: The results show that WFC was associated with an increased risk of emotional exhaustion among both men and women. Gender differences are suggested as WFC was related to an increased risk for poor self-rated health among women and problem drinking among men. Interaction analyses revealed that the risk of poor self-rated health was substantially more influenced by WFC among women than among men. Conclusions: We conclude that, despite the fact that women experience conflict between work and family life slightly more often than men, both men’s and women’s health is negatively affected by this phenomenon. PMID:22683777

  13. Differences in predictors of traditional and cyber-bullying: a 2-year longitudinal study in Korean school children.

    PubMed

    Yang, Su-Jin; Stewart, Robert; Kim, Jae-Min; Kim, Sung-Wan; Shin, Il-Seon; Dewey, Michael E; Maskey, Sean; Yoon, Jin-Sang

    2013-05-01

    Traditional bullying has received considerable research but the emerging phenomenon of cyber-bullying much less so. Our study aims to investigate environmental and psychological factors associated with traditional and cyber-bullying. In a school-based 2-year prospective survey, information was collected on 1,344 children aged 10 including bullying behavior/experience, depression, anxiety, coping strategies, self-esteem, and psychopathology. Parents reported demographic data, general health, and attention-deficit hyperactivity disorder (ADHD) symptoms. These were investigated in relation to traditional and cyber-bullying perpetration and victimization at age 12. Male gender and depressive symptoms were associated with all types of bullying behavior and experience. Living with a single parent was associated with perpetration of traditional bullying while higher ADHD symptoms were associated with victimization from this. Lower academic achievement and lower self esteem were associated with cyber-bullying perpetration and victimization, and anxiety symptoms with cyber-bullying perpetration. After adjustment, previous bullying perpetration was associated with victimization from cyber-bullying but not other outcomes. Cyber-bullying has differences in predictors from traditional bullying and intervention programmes need to take these into consideration. PMID:23640732

  14. Effects of galantamine in a 2-year, randomized, placebo-controlled study in Alzheimer’s disease

    PubMed Central

    Hager, Klaus; Baseman, Alan S; Nye, Jeffrey S; Brashear, H Robert; Han, John; Sano, Mary; Davis, Bonnie; Richards, Henry M

    2014-01-01

    Background Currently available treatments for Alzheimer’s disease (AD) can produce mild improvements in cognitive function, behavior, and activities of daily living in patients, but their influence on long-term survival is not well established. This study was designed to assess patient survival and drug efficacy following a 2-year galantamine treatment in patients with mild to moderately severe AD. Methods In this multicenter, double-blind study, patients were randomized 1:1 to receive galantamine or placebo. One primary end point was safety; mortality was assessed. An independent Data Safety Monitoring Board monitored mortality for the total deaths reaching prespecified numbers, using a time-to-event method and a Cox-regression model. The primary efficacy end point was cognitive change from baseline to month 24, as measured by the Mini-Mental State Examination (MMSE) score, analyzed using intent-to-treat analysis with the ‘last observation carried forward’ approach, in an analysis of covariance model. Results In all, 1,024 galantamine- and 1,021 placebo-treated patients received study drug, with mean age ~73 years, and mean (standard deviation [SD]) baseline MMSE score of 19 (4.08). A total of 32% of patients (661/2,045) completed the study, 27% (554/2,045) withdrew, and 41% (830/2,045) did not complete the study and were discontinued due to a Data Safety Monitoring Board-recommended early study termination. The mortality rate was significantly lower in the galantamine group versus placebo (hazard ratio [HR] =0.58; 95% confidence interval [CI]: 0.37; 0.89) (P=0.011). Cognitive impairment, based on the mean (SD) change in MMSE scores from baseline to month 24, significantly worsened in the placebo (−2.14 [4.34]) compared with the galantamine group (−1.41 [4.05]) (P<0.001). Functional impairment, based on mean (SD) change in the Disability Assessment in Dementia score (secondary end point), at month 24 significantly worsened in the placebo (−10.81 [18

  15. Determinants of “return to work in good health” among workers with back pain who consult in primary care settings: a 2-year prospective study

    PubMed Central

    Bourbonnais, Renée; Frémont, Pierre; Rossignol, Michel; Stock, Susan R.; Nouwen, Arie; Larocque, Isabelle; Demers, Eric

    2006-01-01

    Many factors have been linked to return to work after a back pain episode, but our understanding of this phenomenon is limited and cross-sectional dichotomous indices of return to work are not valid measures of this construct. To describe the course of “return to work in good health” (RWGH—a composite index of back pain outcome) among workers who consulted in primary care settings for back pain and identify its determinants, a 2-year prospective study was conducted. Subjects (n = 1,007, 68.4%) were workers who consulted in primary care settings of the Quebec City area for a nonspecific back pain. They completed five telephone interviews over 2 years (follow-up = 86%). Analyses linking baseline variables with 2-year outcome were conducted with polytomous logistic regression. The proportion of “success” in RWGH increased from 18% at 6 weeks to 57% at 2 years. In women, persistent pain, pain radiating to extremities, increasing job seniority, not having a unionized job, feeling that the physician did listen carefully and increasing fear-avoidance beliefs towards work and activity were determinants of “failure” in RWGH. In men, decreasing age, cigarette smoking, poor self-reported health status, pain in the thoracic area, previous back surgeries, a non-compensated injury, high pain levels, belief that job is below qualifications, likelihood of losing job, job status, satisfaction with health services and fear-avoidance beliefs towards work were all significant. RWGH among workers with back pain receives multiple influences, especially among men. In both genders, however, fear-avoidance beliefs about work are associated with failure and high self-efficacy is associated with success. PMID:16868783

  16. AB142. Discontinuation of dapoxetine treatment in patients with premature ejaculation: a 2-year prospective observational study

    PubMed Central

    Park, Hyun Jun; Park, Nam Cheol

    2015-01-01

    Objective Although dapoxetine is the only oral pharmacological agent approved for the treatment of premature ejaculation (PE) and is very effective, its discontinuation rate is high compared to PDE5 inhibitors in patients with erectile dysfunction (ED). This study assessed the discontinuation rate of dapoxetine treatment in patients with PE and the reasons for discontinuation a clinical setting. Methods The study enrolled 182 consecutive patients [mean age, 38.2 (range, 19-63) years] between October 1, 2011 and September 30, 2013. The PE type (life-long or acquired), self-estimated intravaginal ejaculation latency time (IELT), International Index of Erectile Function-Erectile Function Domain (IIEF-EF) questionnaire, and medical history were checked in all patients. The patients were evaluated 1, 3, 6, 12, and 24 months after initiating therapy regarding the treatment status and the reasons for treatment discontinuation in the case of discontinuation. We compared the discontinuation rates with various parameters and the time interval. Results Of the patients, 9.9% were continuing treatment after 2 years. The discontinuation rate at 1, 3, 6, 12, and 24 months was 26.4%, 35.2%, 17.6%, 8.2%, and 2.7%, respectively. Cumulatively, 79.1% of the patients discontinued the treatment within 6 months. After 12 months, however, the discontinuation rate dropped sharply. The reasons for discontinuation were cost (29.9%), disappointment that PE is not a curable disease and dapoxetine was needed whenever he had sex (25%), side effects (11.6%), low efficacy (9.8%), to seek other treatment options (5.5%), and unknown (18.3%). Patients with acquired PE (vs. life-long), IELT >2 min before treatment, older than 50 years, taking PDE-5 inhibitors, and IIEF-EF <26 tended to discontinue early and had high drop-out rates. Conclusions Of the patients, 9.9% were continuing treatment after 2 years. The discontinuation rate at 1, 3, 6, 12, and 24 months was 26.4%, 35.2%, 17.6%, 8.2%, and 2

  17. Minimally Invasive Periodontal Treatment Using the Er,Cr: YSGG Laser. A 2-year Retrospective Preliminary Clinical Study

    PubMed Central

    Dyer, Bret; Sung, Eric C.

    2012-01-01

    Minimally invasive surgery (MIS) using the erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser (Waterlase MD, Biolase, Irvine, CA) to treat moderate to advanced periodontal disease is presented as an alternative to conventional therapies. To date, there are few short- or long-term studies to demonstrate the effects of this laser in treating and maintaining periodontal health. Electronic clinical records from 16 patients – total of 126 teeth, with pocket depths ranging from 4 mm to 9 mm – were treated with the same protocol using the Er,Cr:YSGG laser. The mean baseline probing depths (PD) were 5 mm and clinical attachment levels (CAL) were 5 mm in the 4 - 6 mm pretreated laser group. The mean baseline probing depths were 7.5 and 7.6 mm for PD and CAL respectfully in the 7 – 9 mm pretreatment laser group. At the 2 year mark, the average PD was 3.2 ± 1.1 mm for the 4-6 mm pocket group and the 7-9 mm pocket group had a mean PD of 3.7 ± 1.2 mm. mean CAL was 3.1 ± 1.1 mm for the 4-6 mm group and 3.6 ± 1.2 for the 7-9 mm group with an overall reduction of 1.9 mm and 4.0 mm respectively. At one and two years, both groups remained stable with PD comparable to the three-month gains. The CAL measurements at one and two years were also comparable to the three-month gains. PMID:22615717

  18. Impact of Nonvascular Thoracic MR Imaging on the Clinical Decision Making of Thoracic Surgeons: A 2-year Prospective Study.

    PubMed

    Ackman, Jeanne B; Gaissert, Henning A; Lanuti, Michael; Digumarthy, Subba R; Shepard, Jo-Anne O; Halpern, Elkan F; Wright, Cameron D

    2016-08-01

    Purpose To determine the impact of nonvascular thoracic magnetic resonance (MR) imaging on the clinical decision making and diagnostic certainty of thoracic surgeons. Materials and Methods Seven thoracic surgeons at Massachusetts General Hospital, an academic quaternary referral hospital, participated in this 2-year, prospective, institution review board-approved, HIPAA-compliant pre- and post-MR imaging survey study after completing a one-time demographic survey. Between July 16, 2013, and July 13, 2015, each time a thoracic surgeon ordered a nonvascular thoracic MR imaging study via radiology order entry, he or she was sent a link to the pre-test survey that ascertained the clinical rationale for MR imaging, the clinical management plan if MR imaging was not an option, and pre-test diagnostic certainty. Upon completion of the MR imaging report, the surgeon was sent a link to the post-test survey assessing if/how MR imaging changed clinical management, the surgeon's comfort with the clinical management plan, and post-test diagnostic certainty. Data were analyzed with Student t, Wilcoxon, and McNemar tests. Results A total of 99 pre- and post-test surveys were completed. Most MR imaging studies (64 of 99 [65%]) were requested because of indeterminate computed tomographic findings. The use of MR imaging significantly reduced the number of planned surgical interventions (P < .001), modified the surgical approach in 54% (14 of 26) of surgical cases, and increased surgeon comfort with the patient management plan in 95% (94 of 99) of cases. Increased diagnostic certainty as a result of MR imaging was highly significant (P < .0001). In 21% (21 of 99) of cases, definitive MR imaging results warranted no further follow-up or clinical care. Conclusion In appropriate cases, assessment with nonvascular thoracic MR imaging substantially affects the clinical decision making and diagnostic certainty of thoracic surgeons. (©) RSNA, 2016 Online supplemental material is available

  19. Retrospective cohort study between selective and standard C3-7 laminoplasty. Minimum 2-year follow-up study

    PubMed Central

    Asazuma, Takashi; Masuoka, Kazunori; Yasuoka, Hiroki; Motosuneya, Takao; Sakai, Tsubasa; Nemoto, Koichi

    2007-01-01

    A total of 64 patients with cervical spondylotic myelopathy (CSM) were assessed in this study. Forty-two patients underwent selective expansive open-door laminoplasty (ELAP). Twenty-two patients who underwent conventional C3-7 ELAP served as controls. There were no significant differences in recovery rate of JOA scores, C2–C7 angle or cervical range of motion between two groups. Incidence of axial symptoms and segmental motor paralysis in selective ELAP was significantly lower than those in the C3-7 ELAP. Size of anterior compression mass, postoperative spinal cord positions and decompression conditions were evaluated using preoperative or postoperative MRI in 50 of 64 patients. There was a positive correlation between number of expanded laminae and maximum anterior spaces of spinal cord. Incomplete decompression was developed in three of 37 patients in selective ELAP and in two of 13 patients in C3-7ELAP. Mean size of anterior compression mass at incomplete decompression levels was significantly greater than that at complete decompression levels. Since, there was less posterior movement of the spinal cord in selective ELAP than that in C3-7ELAP, minute concerns about size of anterior compression mass is necessary to decide the number of expanded laminae. Overall, selective ELAP was less invasive and useful in reducing axial symptoms and segmental motor paralysis. This new surgical strategy was effective in improving the surgical outcomes of CSM, and short-term results were satisfactory. PMID:17726618

  20. A 2-Year, Phase IV, Multicentre, Observational Study of Ranibizumab 0.5 mg in Patients with Neovascular Age-Related Macular Degeneration in Routine Clinical Practice: The EPICOHORT Study

    PubMed Central

    Beatty, Stephen; Perez-Salvador Garcia, Eduardo; Reynders, Stefaan; Si Bouazza, Abdelkader; Pilz, Stefan

    2014-01-01

    Purpose. To assess the safety profile of ranibizumab 0.5 mg in patients with neovascular age-related macular degeneration (nAMD) in routine clinical practice. Methods. This 2-year, multicentre, observational study was conducted to capture real-world early practice and outcomes across Europe, shortly after European licensing of ranibizumab for nAMD. Being observational in nature, the study did not impose diagnostic/therapeutic interventions/visit schedule. Patients were to be treated as per the EU summary of product characteristics (SmPC) in effect during the study. Key outcome measures were incidence of selected adverse events (AEs), treatment exposure, bilateral treatment, compliance to the EU SmPC, and best-corrected visual acuity (BCVA) over 2 years. Results. 755 of 770 patients received treatment. Ranibizumab was generally well tolerated with low incidence of selected AEs (0%–1.9%). Patients received 6.2 (mean) injections and 133 patients received bilateral treatment over 2 years. Protocol deviation to treatment compliance was reported in majority of patients. The observed decline in mean BCVA (Month 12, +1.5; Month 24, –1.3 letters) may be associated with undertreatment as suggested by BCVA subgroup analysis. Conclusion. The EPICOHORT study conducted in routine clinical practice reinforces the well-established safety profile of ranibizumab in nAMD. In early European practice it appeared that the nAMD patients were undertreated. PMID:24868458

  1. Conducting and Reporting Case Studies.

    ERIC Educational Resources Information Center

    Lichtman, Merilyn; Taylor, Satomi Izumi

    Issues and elements of case study research are explored and illustrated with the example of a case study of a kindergarten in a suburb of Tokyo (Japan). Case study research is a type of qualitative research that concentrates on a single unit or entity, with boundaries established by the researcher. The case is an example drawn from a larger class,…

  2. Conducting pilot and feasibility studies.

    PubMed

    Cope, Diane G

    2015-03-01

    Planning a well-designed research study can be tedious and laborious work. However, this process is critical and ultimately can produce valid, reliable study findings. Designing a large-scale randomized, controlled trial (RCT)-the gold standard in quantitative research-can be even more challenging. Even the most well-planned study potentially can result in issues with research procedures and design, such as recruitment, retention, or methodology. One strategy that may facilitate sound study design is the completion of a pilot or feasibility study prior to the initiation of a larger-scale trial. This article will discuss pilot and feasibility studies, their advantages and disadvantages, and implications for oncology nursing research. 
. PMID:25806886

  3. Developmental milestones record - 2 years

    MedlinePlus

    Growth milestones for children - 2 years; Normal childhood growth milestones - 2 years; Childhood growth milestones - 2 years ... a cause for concern if not seen by 2 years.) Can run with better coordination . (May still ...

  4. Developmental milestones record - 2 years

    MedlinePlus

    Growth milestones for children - 2 years; Normal childhood growth milestones - 2 years; Childhood growth milestones - 2 years ... cause for concern if not seen by 2 years.) Can run with better coordination. (May still have ...

  5. Conducting a wind sensing study

    NASA Technical Reports Server (NTRS)

    Byer, R. L.

    1985-01-01

    Signal-to-noise requirements, and how signal-to-noise determines wind velocity measurement accuracy were studied. A Nd:YAG-based system was found to be competitive with a CO2-based system. Hardware was developed for a coherent Nd:YAG LIDAR system, and is being integrated into a functioning system. A diode-pumped monolithic rod laser to be used as a reference oscillator, a high-power, single-mode ring laser, for use as a master oscillator, and a high-gain, multipass amplifier were constructed.

  6. Sporadic community-acquired Legionnaires' disease in France: a 2-year national matched case-control study.

    PubMed

    Che, D; Campese, C; Santa-Olalla, P; Jacquier, G; Bitar, D; Bernillon, P; Desenclos, J-C

    2008-12-01

    Legionnaires' disease (LD) is an aetiology of community-acquired bacterial pneumonia in adults, with a high case-fatality ratio (CFR). We conducted a matched case-control study to identify risk factors for sporadic, community-acquired LD. Cases of sporadic, community-acquired and biologically confirmed LD, in metropolitan France from 1 September 2002 to 31 September 2004, were matched with a control subject according to age, sex, underlying illness and location of residence within 5 km. We performed a conditional logistic regression on various host-related factors and exposures. Analysis was done on 546 matched pairs. The CFR was 3.5%. Age ranged from 18-93 years (mean 57 years), with a 3.6 male:female sex ratio. Cases were more likely to have smoked with the documentation of a dose-effect relation, to have travelled with a stay in a hotel (OR 6.1, 95% CI 2.6-14.2), or to have used a wash-hand basin for personal hygiene (OR 3.5, 95% CI 1.6-7.7) than controls. Tobacco and travel have been previously described as risk factors for LD, but this is the first time that such a dose-effect for tobacco has been documented among sporadic cases. These findings will provide helpful knowledge about LD and help practitioners in identifying patients at high risk. PMID:18211725

  7. Iron-Folic Acid Supplementation During Pregnancy Reduces the Risk of Stunting in Children Less Than 2 Years of Age: A Retrospective Cohort Study from Nepal

    PubMed Central

    Nisar, Yasir Bin; Dibley, Michael J.; Aguayo, Victor M.

    2016-01-01

    The aim of the study was to investigate the effect of antenatal iron-folic acid (IFA) supplementation on child stunting in Nepalese children age <2 years. A retrospective cohort study design was used, in which a pooled cohort of 5235 most recent live births 2 years prior to interview from three Nepal Demographic and Health Surveys (2001, 2006 and 2011) was analysed. The primary outcome was stunting in children age <2 years. The main exposure variable was antenatal IFA supplementation. Multivariate Poisson regression analysis was performed. In our sample, 31% and 10% of Nepalese children age <2 years were stunted and severely stunted, respectively. The adjusted relative risk of being stunted was 14% lower in children whose mothers used IFA supplements compared to those whose mothers did not use (aRR = 0.86, 95% CI = 0.77–0.97). Additionally, the adjusted relative risk of being stunted was significantly reduced by 23% when antenatal IFA supplementation was started ≤6 months with ≥90 IFA supplements used during pregnancy (aRR = 0.77, 95% CI = 0.64–0.92). Antenatal IFA supplementation significantly reduced the risk of stunting in Nepalese children age <2 years. The greatest impact on the risk reduction of child stunting was when IFA supplements were started ≤6 months with ≥90 supplements were used. PMID:26828515

  8. Continuity, Comorbidity and Longitudinal Associations between Depression and Antisocial Behaviour in Middle Adolescence: A 2-Year Prospective Follow-Up Study

    ERIC Educational Resources Information Center

    Ritakallio, Minna; Koivisto, Anna-Maija; von der Pahlen, Bettina; Pelkonen, Mirjami; Marttunen, Mauri; Kaltiala-Heino, Riittakerttu

    2008-01-01

    The study investigated continuity, comorbidity and longitudinal associations between depression Beck depression inventory (RBDI) and antisocial behaviour Youth self-report (YSR) in middle adolescence. Data were used from a community sample of 2070 adolescents who participated in a 2-year prospective follow-up study. The results indicate that both…

  9. Plantar Pressure Changes and Correlating Risk Factors in Chinese Patients with Type 2 Diabetes: Preliminary 2-year Results of a Prospective Study

    PubMed Central

    Qiu, Xuan; Tian, De-Hu; Han, Chang-Ling; Chen, Wei; Wang, Zhan-Jian; Mu, Zhen-Yun; Liu, Kuan-Zhi

    2015-01-01

    Background: Plantar pressure serves as a key factor for predicting ulceration in the feet of diabetes patients. We designed this study to analyze plantar pressure changes and correlating risk factors in Chinese patients with type 2 diabetes. Methods: We recruited 65 patients with type 2 diabetes. They were invited to participate in the second wave 2 years later. The patients completed identical examinations at the baseline point and 2 years later. We obtained maximum force, maximum pressure, impulse, pressure-time integral, and loading rate values from 10 foot regions. We collected data on six history-based variables, six anthropometric variables, and four metabolic variables of the patients. Results: Over the course of the study, significant plantar pressure increases in some forefoot portions were identified (P < 0.05), especially in the second to forth metatarsal heads. Decreases in heel impulse and pressure-time integral levels were also found (P < 0.05). Plantar pressure parameters increased with body mass index (BMI) levels. Hemoglobin A1c (HbA1c) changes were positively correlated with maximum force (β = 0.364, P = 0.001) and maximum pressure (β = 0.366, P = 0.002) changes in the first metatarsal head. Cholesterol changes were positively correlated with impulse changes in the lateral portion of the heel (β = 0.179, P = 0.072) and pressure-time integral changes in the second metatarsal head (β = 0.236, P = 0.020). Ankle-brachial index (ABI) changes were positively correlated with maximum force changes in the first metatarsal head (β = 0.137, P = 0.048). Neuropathy symptom score (NSS) and common peroneal nerve sensory nerve conduction velocity (SCV) changes were positively correlated with some plantar pressure changes. In addition, plantar pressure changes had a correlation with the appearance of infections, blisters (β = 0.244, P = 0.014), and calluses over the course of the study. Conclusions: We should pay attention to the BMI, HbA1c, cholesterol, ABI

  10. Do Deviant Peer Associations Mediate the Contributions of Self-Esteem to Problem Behavior During Early Adolescence? A 2-Year Longitudinal Study

    ERIC Educational Resources Information Center

    DuBois, David L.; Silverthorn, Naida

    2004-01-01

    We investigated deviant peer associations as a mediator of the influences of general and peer-oriented self-esteem on problem behavior using data from a 2-year longitudinal study of 350 young adolescents. Measures of problem behavior included substance use (alcohol use, smoking) and antisocial behavior (fighting, stealing). Using latent growth…

  11. The Role of Pictures and Gestures as a Support Mechanism for Novel Word Learning: A Training Study with 2-Year-Old Children

    ERIC Educational Resources Information Center

    Kapalková, Svetlana; Polišenská, Kamila; Süssová, Martina

    2016-01-01

    A training study examined novel word learning in 2-year-old children and assessed two nonverbal mechanisms, pictures and gestures, which are commonly used as communication support. The aim was to (1) compare these two support mechanisms and measure their effects on expressive word learning and (2) to investigate these effects on word production…

  12. Exploring the Relationship between Autistic-Like Traits and ADHD Behaviors in Early Childhood: Findings from a Community Twin Study of 2-Year-Olds

    ERIC Educational Resources Information Center

    Ronald, Angelica; Edelson, Lisa R.; Asherson, Philip; Saudino, Kimberly J.

    2010-01-01

    Behaviors characteristic of autism and ADHD emerge in early childhood, yet research investigating their comorbidity has focused on older children. This study aimed to explore the nature of the relationship between autistic-like traits and ADHD behaviors in a community sample of 2-year-olds. Twins from the Boston University Twin Project (N = 312…

  13. A retrospective study of radiographic abnormalities in the repositories of 2-year-old Thoroughbred in-training sales in Japan

    PubMed Central

    MIYAKOSHI, Daisuke; SENBA, Hiroyuki; SHIKICHI, Mitsumori; MAEDA, Masaya; SHIBATA, Ryo; MISUMI, Kazuhiro

    2016-01-01

    ABSTRACT This study aimed to evaluate the influence of radiographic abnormalities of 2-year-old Thoroughbred horses that were listed at in-training sales in Japan, on whether they started to race or not at 2–3 years of age. Radiographs of 850 2-year-old Thoroughbreds in the in-training sales repository from 2007 to 2010 were reviewed, and 26 categories of radiographic abnormalities were found. Forty-three horses (5.1%, 43/850) did not start a race at 2–3 years of age. In accordance with the racing results for this age category, as determined by Fisher’s exact test and multiple logistic regression analysis, none of the radiographic abnormalities were significantly related to failure to start a race. At 2 years of age, 198 horses (23.3%, 198/850) did not start a race. Horses with enlargement of the proximal sesamoid bones in the fore (9 of 19 horses) and hind limbs (5 of 9 horses) did not start a race at the age of 2 years, and fewer of these horses (fore, P=0.021; hind, P=0.030) started a race at the age of 2 years compared with the population of horses without these radiographic abnormalities. These results suggest that identification of radiographic enlargement of the proximal sesamoid bones during training sales could derail the racing debut of horses at the age of 2 years. However, this might not necessarily indicate a poor prognosis and resulting in retirement from racing at 2–3 years of age. PMID:27330400

  14. Long-term impact of a chef on school lunch consumption: findings from a 2-year pilot study in Boston middle schools.

    PubMed

    Cohen, Juliana F W; Smit, Liesbeth A; Parker, Ellen; Austin, S Bryn; Frazier, A Lindsay; Economos, Christina D; Rimm, Eric B

    2012-06-01

    School cafeterias can play an important role in providing healthy meals. Although schools participating in the National School Lunch Program are required to meet minimum program standards, advocates recommend that innovations be sought to enhance menu dietary quality. This study evaluated the Chef Initiative, a 2-year pilot study in two Boston middle schools, designed to increase the availability and consumption of healthier school foods. Between 2007 and 2009, a professional chef trained cafeteria staff to prepare healthier school lunches (ie, more whole grains, fresh/frozen fruits and vegetables, and less sugar, salt, saturated fats, and trans fats). Meal nutrient compositions were monitored from 2007 to 2009, and a plate waste study conducted in the spring of 2009 compared food selection and consumption patterns among students at Chef Initiative schools, with students receiving standard school lunches at two matched control schools. Paired t tests and descriptive statistics were used to examine differences in menus and mixed-model analysis of variance was used to analyze differences in students' food selection and consumption between Chef Initiative and control schools. Overall, the Chef Initiative schools provided healthier lunches and the percent of foods consumed at Chef Initiative and control schools were similar (61.6% vs 57.3%; P=0.63). Of the areas targeted, there was greater whole-grain selection and vegetable consumption; 51% more students selected whole grains (P=0.02) and students consumed 0.36 more vegetable servings/day (P=0.01) at Chef Initiative schools. The potential of chefs collaborating with cafeteria staff to improve the availability, selection, and consumption of healthier meals is promising. PMID:22504283

  15. Imaging of the dopamine transporter predicts pattern of disease progression and response to levodopa in patients with schizophrenia and parkinsonism: a 2-year follow-up multicenter study.

    PubMed

    Tinazzi, Michele; Morgante, Francesca; Matinella, Angela; Bovi, Tommaso; Cannas, Antonino; Solla, Paolo; Marrosu, Francesco; Nicoletti, Alessandra; Zappia, Mario; Luca, Antonina; Di Stefano, Angela; Morgante, Letterio; Pacchetti, Claudio; Minafra, Brigida; Sciarretta, Massimo; Dallocchio, Carlo; Rossi, Simone; Ulivelli, Monica; Ceravolo, Roberto; Frosini, Daniela; Cipriani, Andrea; Barbui, Corrado

    2014-02-01

    Similarly to subjects with degenerative parkinsonism, (123)I-FP-CIT SPECT has been reported either normal or abnormal in patients with drug-induced parkinsonism (DIP), challenging the notion that parkinsonism might be entirely due to post-synaptic D2-receptors blockade by antipsychotic drugs. In a previous multicenter cross-sectional study conducted on a large sample of patients with schizophrenia, we identified 97 patients who developed parkinsonism with a similar bi-modal distribution of DAT-SPECT. In this longitudinal study, we reported clinical and imaging features associated with progression of motor disability over 2-year follow-up in 60 out of those 97 patients with schizophrenia and parkinsonism who underwent (123)I-FP-CIT SPECT at baseline evaluation (normal SPECT=33; abnormal SPECT=27). As second end-point, chronic response to levodopa over a 3-month period was tested in a subgroup of subjects. Motor Unified Parkinson's Disease Rating Scale (UPDRS) at follow-up significantly increased in patients with abnormal SPECT. Specifically, a 6-point worsening was demonstrated in 18.5% of the subjects with abnormal SPECT and in none of the subjects with normal SPECT. Levodopa treatment improved motor UPDRS only in the group with abnormal SPECT. After adjustment for possible confounders, linear regression analysis demonstrated that abnormal SPECT findings at baseline were the only predictor of motor disability progression and of better outcome of levodopa treatment. Our results support the notion that a degenerative disease might underlie parkinsonism in a minority of schizophrenic patients chronically exposed to antipsychotics. Functional imaging of the dopamine transporter can be helpful to select this patient sub-group that might benefit from levodopa therapy. PMID:24369987

  16. Increased Regulatory T-Cell Percentage Contributes to Poor CD4+ Lymphocytes Recovery: A 2-Year Prospective Study After Introduction of Antiretroviral Therapy

    PubMed Central

    Saison, Julien; Maucort Boulch, Delphine; Chidiac, Christian; Demaret, Julie; Malcus, Christophe; Cotte, Laurent; Poitevin-Later, Francoise; Miailhes, Patrick; Venet, Fabienne; Trabaud, Mary Anne; Monneret, Guillaume; Ferry, Tristan

    2015-01-01

    Background. The primary aim of this study was to determine the impact of regulatory T cells (Tregs) percentage on immune recovery in human immunodeficiency virus (HIV)-infected patients after antiretroviral therapy introduction. Methods. A 2-year prospective study was conducted in HIV-1 chronically infected naive patients with CD4 count <500 cells/mm3. Regulatory T cells were identified as CD4+CD25highCD127low cells among CD4+ lymphocytes. Effect of Treg percentage at inclusion on CD4 evolution overtime was analyzed using a mixed-effect Poisson regression for count data. Results. Fifty-eight patients were included (median CD4 = 293/mm3, median Treg percentage = 6.1%). Percentage of Treg at baseline and CD4 nadir were independently related to the evolution of CD4 absolute value according to time: (1) at any given nadir CD4 count, 1% increase of initial Treg was associated with a 1.9% lower CD4 absolute value at month 24; (2) at any given Treg percentage at baseline, 10 cell/mm3 increase of CD4 nadir was associated with a 2.4% increase of CD4 at month 24; and (3) both effects did not attenuate with time. The effect of Treg at baseline on CD4 evolution was as low as the CD4 nadir was high. Conclusions. Regulatory T-cell percentage at baseline is a strong independent prognostic factor of immune recovery, particularly among patients with low CD4 nadir. PMID:26110165

  17. Trait and State Attributes of Insight in First Episodes of Early-Onset Schizophrenia and Other Psychoses: A 2-Year Longitudinal Study

    PubMed Central

    Parellada, Mara; Boada, Leticia; Fraguas, David; Reig, Santiago; Castro-Fornieles, Josefina; Moreno, Dolores; Gonzalez-Pinto, Ana; Otero, Soraya; Rapado-Castro, Marta; Graell, Montserrat; Baeza, Inmaculada; Arango, Celso

    2011-01-01

    Background: Increasing evidence supports the important role of illness state and individual characteristics in insight. Methods: Insight, as measured with the Scale to Assess Unawareness of Mental Disorder, over the first 2 years of early-onset first-episode psychosis and its correlations with clinical, socio-demographic, cognitive, and structural brain variables are studied. Results: (1) insight at 2 years is poorer in schizophrenia spectrum disorders (SSDs) than in subjects with other psychoses; (2) the more severe the psychosis, the worse the insight. In SSD, depressive symptoms, poorer baseline executive functioning, lower IQ, longer duration of untreated psychosis (DUP), and poorer premorbid infancy adjustment are associated with poorer insight; frontal and parietal gray matter (GM) reductions at baseline correlate with worse insight into having psychotic symptoms at 2 years; (3) insight into having a mental disorder (Scale to Assess Unawareness of Mental Disorder [SUMD]1) at 1 year, DUP, and baseline IQ are the most consistent variables explaining different aspects of insight at 2 years in SSD patients. IQ and SUMD1 at 1 year, together with left frontal and parietal GM volumes, explain 80% of the variance of insight into having specific psychotic symptoms in SSD patients (adjusted R2 = 0.795, F = 15.576, P < .001). Conclusion: Insight is a complex phenomenon that depends both on severity of psychopathology and also on disease and subject characteristics, such as past adjustment, IQ, DUP, cognitive functioning, frontal and parietal GM volumes, and age, gender, and ethnicity. PMID:20884756

  18. Diurnal Cortisol Secretion at Home and in Child Care: A Prospective Study of 2-Year-Old Toddlers

    ERIC Educational Resources Information Center

    Ouellet-Morin, Isabelle; Tremblay, Richard E.; Boivin, Michel; Meaney, Michael; Kramer, Michael; Cote, Sylvana M.

    2010-01-01

    Background: Previous studies indicate that children may experience disrupted cortisol secretion in child care. The extent to which this is a transient or long-term disruption is not known, as most studies have relied on cross-sectional designs, and age-heterogeneous small sample sizes. This study aims to (a) compare cortisol secretion measured at…

  19. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the removal process, remedial investigation/ feasibility study (RI/FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response...

  20. The Role of Behavioral Self-Regulation in Learning to Read: A 2-Year Longitudinal Study of Icelandic Preschool Children

    ERIC Educational Resources Information Center

    Birgisdóttir, Freyja; Gestsdóttir, Steinunn; Thorsdóttir, Fanney

    2015-01-01

    Research Findings: Research suggests that behavioral self-regulation skills are critical for early school success, including success in literacy, but few studies have explored the relations that behavioral self-regulation may have with different components of early literacy development. The present study investigated the longitudinal contribution…

  1. The Predictive Relationship between Temperament, School Adjustment, and Academic Achievement: A 2-Year Longitudinal Study of Children At-Risk

    ERIC Educational Resources Information Center

    Al-Hendawi, Maha

    2010-01-01

    Individual differences in temperament can be a risk or a protective factor for a child, especially for children at-risk who possess single or multiple risk factors that may interfere with their educational success and affect their healthy development and their life-long outcomes. This research study examined the concurrent and longitudinal…

  2. Illness Uncertainty and Quality of Life of Patients with Small Renal Tumors Undergoing Watchful Waiting: A 2-year Prospective Study

    PubMed Central

    Parker, Patricia A.; Alba, Frances; Fellman, Bryan; Urbauer, Diana L.; Li, Yisheng; Karam, Jose A.; Tannir, Nizar; Jonasch, Eric; Wood, Christopher G.; Matin, Surena F.

    2013-01-01

    Background Few studies have examined factors associated with the quality of life (QOL) of patients with renal tumors. Illness uncertainty may influence QOL. Objective To prospectively examine the influence of uncertainty on general and cancer-specific QOL and distress in patients undergoing watchful waiting (WW) for a renal mass. Design, setting, and participants In 2006–2010, 264 patients were enrolled in a prospective WW registry. The decision for WW was based on patient, tumor, and renal function characteristics at the discretion of the urologist and medical oncologist in the context of the physician–patient interaction. Participants had suspected clinical stage T1–T2 disease, were aged ≥18 yr, and spoke and read English. The first 100 patients enrolled in the registry participated in this study. Outcome measurements and statistical analysis Patients completed questionnaires on demographics, illness uncertainty (Mishel Uncertainty in Illness Scale), general QOL (Medical Outcomes Study 36-item short-form survey), cancer-specific QOL (Cancer Rehabilitation Evaluation System–Short Form), and distress (Impact of Events Scale) at enrollment and at 6, 12, and 24 mo. Age, gender, ethnicity, tumor size, estimated glomerular filtration rate, comorbidities, and assessment time point were controlled for in the models. Results and limitations Among the sample, 27 patients had biopsies, and 17 patients had proven renal cell carcinoma. Growth rate was an average of 0.02 cm/yr (standard deviation: 0.03). Mean age was 72.5 yr, 55% of the patients were male, and 84% of the patients were Caucasian. Greater illness uncertainty was associated with poorer general QOL scores in the physical domain (p = 0.008); worse cancer-related QOL in physical (p = 0.001), psychosocial (p < 0.001), and medical (p = 0.034) domains; and higher distress (p < 0.001). Conclusions This study is among the first to prospectively examine the QOL of patients with renal tumors undergoing WW and the

  3. Acoustic evidence for the development of gestural coordination in the speech of 2-year-olds: a longitudinal study.

    PubMed

    Goodell, E W; Studdert-Kennedy, M

    1993-08-01

    Studies of child phonology have often assumed that young children first master a repertoire of phonemes and then build their lexicon by forming combinations of these abstract, contrastive units. However, evidence from children's systematic errors suggests that children first build a repertoire of words as integral sequences of gestures and then gradually differentiate these sequences into their gestural and segmental components. Recently, experimental support for this position has been found in the acoustic records of the speech of 3-, 5-, and 7-year-old children, suggesting that even in older children some phonemes have not yet fully segregated as units of gestural organization and control. The present longitudinal study extends this work to younger children (22- and 32-month-olds). Results demonstrate clear differences in the duration and coordination of gestures between children and adults, and a clear shift toward the patterns of adult speakers during roughly the third year of life. Details of the child-adult differences and developmental changes vary from one aspect of an utterance to another. PMID:8377484

  4. Cardiovascular Effects of Dietary Salt Intake in Aged Healthy Cats: A 2-Year Prospective Randomized, Blinded, and Controlled Study

    PubMed Central

    Chetboul, Valérie; Reynolds, Brice Stéphane; Trehiou-Sechi, Emilie; Nguyen, Patrick; Concordet, Didier; Sampedrano, Carolina Carlos; Testault, Isabelle; Elliott, Jonathan; Abadie, Jérôme; Biourge, Vincent; Lefebvre, Hervé Pierre

    2014-01-01

    High salt dry expanded diets are commercially available for cats to increase water intake and urine volume, as part of the prevention or treatment of naturally occurring urinary stone formation (calcium oxalates and struvites). However, chronic high salt intake may have potential cardiovascular adverse effects in both humans, especially in aging individuals, and several animal models. The objective of this prospective, randomized, blinded, and controlled study was to assess the long-term cardiovascular effects of high salt intake in healthy aged cats. Twenty healthy neutered cats (10.1±2.4 years) were randomly allocated into 2 matched groups. One group was fed a high salt diet (3.1 g/Mcal sodium, 5.5 g/Mcal chloride) and the other group a control diet of same composition except for salt content (1.0 g/Mcal sodium, 2.2 g/Mcal chloride). Clinical examination, systolic and diastolic arterial blood pressure measurements, standard transthoracic echocardiography and conventional Doppler examinations were repeatedly performed on non-sedated cats by trained observers before and over 24 months after diet implementation. Radial and longitudinal velocities of the left ventricular free wall and the interventricular septum were also assessed in systole and diastole using 2-dimensional color tissue Doppler imaging. Statistics were performed using a general linear model. No significant effect of dietary salt intake was observed on systolic and diastolic arterial blood pressure values. Out of the 33 tested imaging variables, the only one affected by dietary salt intake was the radial early on late diastolic velocity ratio assessed in the endocardium of the left ventricular free wall, statistically lower in the high salt diet group at 12 months only (P = 0.044). In conclusion, in this study involving healthy aged cats, chronic high dietary salt intake was not associated with an increased risk of systemic arterial hypertension and myocardial dysfunction, as observed in some

  5. Duration of untreated psychosis predicts functional and clinical outcome in children and adolescents with first-episode psychosis: a 2-year longitudinal study.

    PubMed

    Fraguas, David; Del Rey-Mejías, Angel; Moreno, Carmen; Castro-Fornieles, Josefina; Graell, Montserrat; Otero, Soraya; Gonzalez-Pinto, Ana; Moreno, Dolores; Baeza, Inmaculada; Martínez-Cengotitabengoa, Mónica; Arango, Celso; Parellada, Mara

    2014-01-01

    Longer duration of untreated psychosis (DUP) in adult patients with first-episode psychosis (FEP) has been associated with poor clinical and social outcomes. We aimed to estimate the influence of DUP on outcome at 2-year follow-up in subjects with an early-onset (less than 18 years of age) FEP of less than 6 months' duration. A total of 80 subjects (31.3% females, mean age 16.0±1.8 years) were enrolled in the study. The influence of DUP on outcome was estimated using multiple regression models (two linear models for influence of DUP on the C-GAF at 2 years and C-GAF change through the follow-up period, and a logistic model for influence of DUP on 41 PANSS remission at 2 years in schizophrenia patients (n=47)). Mean DUP was 65.3±54.7 days. Median DUP was 49.5 days. For the whole sample (n=80), DUP was the only variable significantly related to C-GAF score at 2-year follow-up (Beta=-0.13, p<0.01), while DUP and premorbid adjustment (Beta=-0.01, p<0.01; and Beta=-0.09, p=0.04, respectively) were the only variables significantly related to C-GAF change. In schizophrenia patients, DUP predicted both C-GAF score at 2 years and C-GAF change, while in patients with affective psychosis (n=22), DUP was unrelated to outcome. Lower baseline C-GAF score (OR=0.91, p<0.01) and shorter DUP (OR=0.98, p=<0.01) were the only variables that significantly predicted clinical remission in schizophrenia patients. In conclusion, longer DUP was associated with lower C-GAF at 2 years, less increase in C-GAF, and lower rates of clinical remission in early-onset FEP. Our findings support the importance of early detection programs, which help shorten DUP. PMID:24332406

  6. 2-year study of chemical composition of bulk deposition in a South China coastal city: comparison with East Asian cities

    SciTech Connect

    K.M. Wai; P.A. Tanner; C.W.F. Tam

    2005-09-01

    Using the emission strengths of the precursor gases, the nature of soil in China, the ventilation power and half value rainout region length, the nss-SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, Ca{sup 2+}, and NH{sub 4}{sup +} concentrations, and pH of rainwater at Hong Kong and other cities of China and Japan are compared and rationalized. The chemical composition of Hong Kong bulk deposition from 1998 to 2000 is taken from the collection and analysis of 156 daily samples. The volume-weighted average (VWA) pH is 4.2 over the whole study period. Nonsea salt- (nss-) sulfate is the most abundant species in the samples, and the pH mostly depended upon the concentrations of the major species nss-SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, Ca{sup 2+}, and NH{sub 4}{sup +}. All species concentrations show higher levels in the cold season (especially NO{sub 3}- and Ca{sup 2+}), which indicates the dominant dilution effects in the warm season due to heavy rainfall and the influence of the continental outflow of pollutants during the cold season. For Hong Kong bulk deposition, the VWA pH is slightly lower in the cold season, and there is a slight decrease in VWA pH over the period from 1994 to 2000. The impact of acid rain in Hong Kong is briefly discussed. 36 refs., 3 figs., 5 tabs.

  7. 2-year study of chemical composition of bulk deposition in a south China coastal city: comparison with east Asian cities.

    PubMed

    Wai, K M; Tanner, P A; Tam, C W F

    2005-09-01

    Using the emission strengths of the precursor gases, the nature of soil in China, the ventilation power and half value rainout region length, the nss-SO42-, NO3-, Ca2+, and NH4+ concentrations, and pH of rainwater at Hong Kong and other cities of China and Japan are compared and rationalized. The chemical composition of Hong Kong bulk deposition from 1998 to 2000 is taken from our collection and analysis of 156 daily samples. The volume-weighted average (VWA) pH is 4.2 over the whole study period. Nonsea salt- (nss-) sulfate is the most abundant species in the samples, and the pH mostly depended upon the concentrations of the major species nss-SO42, NO3-, Ca2+, and NH4+. All species concentrations show higher levels in the cold season (especially NO3- and Ca2+), which indicates the dominant dilution effects in the warm season due to heavy rainfall and the influence of the continental outflow of pollutants during the cold season. For Hong Kong bulk deposition, the VWA pH is slightly lower in the cold season, and there is a slight decrease in VWA pH over the period from 1994 to 2000. The impact of acid rain in Hong Kong is briefly discussed. PMID:16190210

  8. Prevalence of and risk factors for persistent postoperative nonanginal pain after cardiac surgery: a 2-year prospective multicentre study

    PubMed Central

    Choinière, Manon; Watt-Watson, Judy; Victor, J. Charles; Baskett, Roger J.F.; Bussières, Jean S.; Carrier, Michel; Cogan, Jennifer; Costello, Judy; Feindel, Christopher; Guertin, Marie-Claude; Racine, Mélanie; Taillefer, Marie-Christine

    2014-01-01

    Background: Persistent postoperative pain continues to be an underrecognized complication. We examined the prevalence of and risk factors for this type of pain after cardiac surgery. Methods: We enrolled patients scheduled for coronary artery bypass grafting or valve replacement, or both, from Feb. 8, 2005, to Sept. 1, 2009. Validated measures were used to assess (a) preoperative anxiety and depression, tendency to catastrophize in the face of pain, health-related quality of life and presence of persistent pain; (b) pain intensity and interference in the first postoperative week; and (c) presence and intensity of persistent postoperative pain at 3, 6, 12 and 24 months after surgery. The primary outcome was the presence of persistent postoperative pain during 24 months of follow-up. Results: A total of 1247 patients completed the preoperative assessment. Follow-up retention rates at 3 and 24 months were 84% and 78%, respectively. The prevalence of persistent postoperative pain decreased significantly over time, from 40.1% at 3 months to 22.1% at 6 months, 16.5% at 12 months and 9.5% at 24 months; the pain was rated as moderate to severe in 3.6% at 24 months. Acute postoperative pain predicted both the presence and severity of persistent postoperative pain. The more intense the pain during the first week after surgery and the more it interfered with functioning, the more likely the patients were to report persistent postoperative pain. Pre-existing persistent pain and increased preoperative anxiety also predicted the presence of persistent postoperative pain. Interpretation: Persistent postoperative pain of nonanginal origin after cardiac surgery affected a substantial proportion of the study population. Future research is needed to determine whether interventions to modify certain risk factors, such as preoperative anxiety and the severity of pain before and immediately after surgery, may help to minimize or prevent persistent postoperative pain. PMID:24566643

  9. A longitudinal study of Giardia duodenalis genotypes in dairy cows from birth to 2 years of age.

    PubMed

    Santín, Mónica; Trout, James M; Fayer, Ronald

    2009-05-26

    Fecal specimens were collected from 30 calves from birth to 24 months of age at a dairy farm in Maryland to determine the prevalence of Giardia duodenalis genotypes in cattle of different ages. Fecal samples were subjected to density gradient centrifugation to remove debris and concentrate cysts. Specimens were analyzed by immunofluorescence microscopy and polymerase chain reaction (PCR). All PCR positive specimens were sequenced using the SSU-rRNA gene of Giardia. All 30 calves shed G. duodenalis cysts at some time during the study. Of 990 specimens, 312 were positive for G. duodenalis (31.5%). The highest prevalence of infection occurred at weeks 4 and 5 of age with 25 out of 30 calves shedding cysts at those sampling times. Overall, pre-weaned calves (<8 weeks of age) exhibited the highest prevalence (60.8%), followed by post-weaned calves (3-12 months of age) (32.1%) and heifers (12-24 months of age) (11.4%). Sequence analysis of the 312 PCR-positive samples revealed the presence of both Assemblages A and E, G. duodenalis, with cumulative prevalences of 70% and 100%, respectively. Assemblage A was not detected in pre-weaned calves, but was detected in 6.9% and 4.7% of post-weaned calves and heifers, respectively. These data indicate not only that calves are infected with both Assemblages A and E simultaneously, but also that infections with zoonotic Assemblage A, G. duodenalis are more common than previously reported. Thus, calves appear to be a more significant reservoir of human infectious G. duodenalis than previous data have suggested. PMID:19264407

  10. Prospective Study Evaluating Postoperative Radiotherapy Plus 2-Year Androgen Suppression for Post-Radical Prostatectomy Patients With Pathologic T3 Disease and/or Positive Surgical Margins

    SciTech Connect

    Choo, Richard Danjoux, Cyril; Gardner, Sandra; Morton, Gerard; Szumacher, Ewa; Loblaw, D. Andrew; Cheung, Patrick; Pearse, Maria

    2009-10-01

    Purpose: To determine the efficacy of a combined approach of postoperative radiotherapy (RT) plus 2-year androgen suppression (AS) for patients with pathologic T3 disease (pT3) and/or positive surgical margins (PSM) after radical prostatectomy (RP). Methods and Materials: A total of 78 patients with pT3 and/or PSM after RP were treated with RT plus 2-year AS, as per a pilot, prospective study. Androgen suppression started within 1 month after the completion of RT and consisted of nilutamide for 4 weeks and buserelin acetate depot subcutaneously every 2 months for 2 years. Relapse-free rate, including freedom from prostate-specific antigen (PSA) relapse, was estimated using the Kaplan-Meier method. A Cox regression analysis was performed to evaluate prognostic factors for relapse. Prostate-specific antigen relapse was defined as a PSA rise above 0.2 ng/mL, with two consecutive increases over a minimum of 3 months. Results: The median age was 61 years at the time of RP. The median interval between RP and postoperative RT was 4.2 months. Forty-nine patients had undetectable PSA (<0.2 ng/mL), and 29 had persistently detectable postoperative PSA at the time of the protocol treatment. Median follow-up from RT was 6.4 years. Relapse-free rates at 5 and 7 years were 94.4% and 86.3%, respectively. Survival rates were 96% at 5 years and 93.1% at 7 years. On Cox regression analysis, persistently detectable postoperative PSA and pT3b-T4 were significant predictors for relapse. Conclusion: The combined treatment of postoperative RT plus 2-year AS yielded encouraging results for patients with pT3 and/or PSM and warrants a confirmatory study.

  11. Cementless anatomical prosthesis for the treatment of 3-part and 4-part proximal humerus fractures: cadaver study and prospective clinical study with minimum 2 years followup

    PubMed Central

    Obert, Laurent; Saadnia, Rachid; Loisel, François; Uhring, Julien; Adam, Antoine; Rochet, Séverin; Clappaz, Pascal; Lascar, Tristan

    2016-01-01

    Introduction: The purpose of this study was to evaluate the functional and radiological outcomes of a cementless, trauma-specific locked stem for 3- and 4-part proximal humeral fractures. Materials and methods: This study consisted of two parts: a cadaver study with 22 shoulders and a multicenter prospective clinical study of 23 fracture patients evaluated at least 2 years after treatment. In the cadaver study, the locked stem (HumelockTM, FX Solutions) and its instrumentation were evaluated. In the clinical study, five senior surgeons at four different hospitals performed the surgical procedures. An independent surgeon evaluated the patients using clinical (Constant score, QuickDASH) and radiological (X-rays, CT scans) outcome measures. Results: The cadaver study allowed us to validate the height landmarks relative to the pectoralis major tendon. In the clinical study, at the review, abduction was 95° (60–160), forward flexion was 108° (70–160), external rotation (elbow at body) was 34° (0–55), the QuickDASH was 31 (4.5–59), the overall Constant score was 54 (27–75), and the weighted Constant score was 76 (31.5–109). Discussion: This preliminary study of hemiarthroplasty (HA) with a locked stem found results that were at least equivalent to published series. As all patients had at least a 2-year follow-up, integration of the locked stem did not cause any specific complications. These results suggest that it is possible to avoid using cement when hemiarthroplasty is performed for the humeral stem. This implant makes height adjustment and transosseous suturing of the tuberosities more reproducible. PMID:27194107

  12. Parental Estimation of Their Child's Increased Type 1 Diabetes Risk During the First 2 Years of Participation in an International Observational Study: Results From the TEDDY study.

    PubMed

    Swartling, Ulrica; Lynch, Kristian; Smith, Laura; Johnson, Suzanne Bennett

    2016-04-01

    This study assessed mothers' and fathers' perception of their child's risk of getting type 1 diabetes (T1D) during the first 2 years of their participation in The Environmental Determinants of Diabetes in the Young (TEDDY) study. TEDDY parents were informed of their child's increased genetic risk for T1D at study inception. Parent perception of the child's risk was assessed at 3, 6, 15, and 27 months of age. In families with no history of T1D, underestimation of the child's T1D risk was common in mothers (>38%) and more so in fathers (>50%). The analyses indicated that parental education, country of residence, family history of T1D, household crowding, ethnic minority status, and beliefs that the child's T1D risk can be reduced were factors associated with parental risk perception accuracy. Even when given extensive information about their child's T1D risk, parents often fail to accurately grasp the information provided. This is particularly true for fathers, families from low socioeconomic backgrounds, and those with no family history of T1D. It is important to develop improved tools for risk communication tailored to individual family needs. PMID:27241873

  13. Joint unloading implant modifies subchondral bone trabecular structure in medial knee osteoarthritis: 2-year outcomes of a pilot study using fractal signature analysis

    PubMed Central

    Miller, Larry E; Sode, Miki; Fuerst, Thomas; Block, Jon E

    2015-01-01

    Background Knee osteoarthritis (OA) is largely attributable to chronic excessive and aberrant joint loading. The purpose of this pilot study was to quantify radiographic changes in subchondral bone after treatment with a minimally invasive joint unloading implant (KineSpring® Knee Implant System). Methods Nine patients with unilateral medial knee OA resistant to nonsurgical therapy were treated with the KineSpring System and followed for 2 years. Main outcomes included Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, function, and stiffness subscores and independent core laboratory determinations of joint space width and fractal signature of the tibial cortex. Results WOMAC scores, on average, improved by 92% for pain, 91% for function, and 79% for stiffness over the 2-year follow-up period. Joint space width in the medial compartment of the treated knee significantly increased from 0.9 mm at baseline to 3.1 mm at 2 years; joint space width in the medial compartment of the untreated knee was unchanged. Fractal signatures of the vertically oriented trabeculae in the medial compartment decreased by 2.8% in the treated knee and increased by 2.1% in the untreated knee over 2 years. No statistically significant fractal signature changes were observed in the horizontally oriented trabeculae in the medial compartment or in the horizontal or vertical trabeculae of the lateral compartment in the treated knee. Conclusion Preliminary evidence suggests that the KineSpring System may modify knee OA disease progression by increasing joint space width and improving subchondral bone trabecular integrity, thereby reducing pain and improving joint function. PMID:25670891

  14. Proton Conductivity Studies on Biopolymer Electrolytes

    SciTech Connect

    Harun, N. I.; Sabri, N. S.; Rosli, N. H. A.; Taib, M. F. M.; Saaid, S. I. Y.; Kudin, T. I. T.; Ali, A. M. M.; Yahya, M. Z. A.

    2010-07-07

    Proton conducting solid biopolymer electrolyte membranes consisting of methyl cellulose (MC) and different wt.% of ammonium nitrate (NH{sub 4}NO{sub 3}) were prepared by solution cast technique. Impedance spectroscopy was carried out to study electrical characteristics of bulk materials. The ionic conductivity of the prepared samples was calculated using the bulk resistance (R{sub b}) obtained from impedance spectroscopy plot. The highest ionic conductivity obtained was 1.17x10{sup -4} Scm{sup -1} for the sample with composition ratio of MC(50): NH{sub 4}NO{sub 3}(50). To enhance the ionic conductivity, propylene carbonate (PC) and ethylene carbonate (EC) plasticizers were introduced. It was found that the ionic conductivity of polymer electrolyte membranes increased with the increase in plasticizers concentration. The ionic conductivities of solid polymer electrolytes based on MC-NH{sub 4}NO{sub 3}-PC was enhanced up to 4.91x10{sup -3} Scm{sup -1} while for the MC-NH{sub 4}NO{sub 3}-EC system, the highest conductivity was 1.74x10{sup -2} Scm{sup -1}. The addition of more plasticizer however decreases in mechanical stability of the membranes.

  15. A study of the efficacy and safety of albendazole (Zentel) in the treatment of intestinal helmenthiasis in Kenyan children less than 2 years of age.

    PubMed

    Pamba, H O; Bwibo, N O; Chunge, C N; Estambale, B B

    1989-03-01

    One hundred children comprising of 57 males and 43 females aged between 8 and 24 months entered the study. 46 children had single and 54 children had multiple helminth infections. All children received albendazole 200 mg (10 ml) suspension as a single dose. Albendazole proved very effective and safe in the treatment of single and multiple helminth infections in children under 2 years of age, achieving cure rates of 100% in both Ascaris lumbricoides and Necator americanus respectively, 83% in Trichuris trichiura and 66% in Hymenolepis nana. Treatment of polyparasitism appears to be of benefit in improving nutritional status using haemoglobin concentrations as an index. PMID:2591328

  16. Principles and pitfalls of nerve conduction studies.

    PubMed

    Kimura, J

    1984-10-01

    This report reviews the fundamental principles and the changing concepts of nerve stimulation techniques, and discusses the proper application of these techniques in the differential diagnosis of peripheral nerve disorders. Nerve conduction studies help delineate the extent and distribution of the neural lesion and distinguish two major categories of peripheral nerve disease: demyelination and axonal degeneration. Although the method is based on simple principles, pitfalls abound in practice. Variability in nerve conduction measurement may result from temperature change, variations among nerve segments, and the effects of age. Other sources of error include excessive spread of stimulation current, anomalous innervation, temporal dispersion, and inaccuracy of surface measurement. Unlike a bipolar derivation, which selectively records near-field potentials, a referential recording may give rise to stationary far-field peaks from a moving source. Overlooking this possibility can lead to an incorrect interpretation of findings. Conventional nerve conduction studies deal primarily with measurements of the distal nerve segments in an extremity. More recent techniques are applicable to less accessible anatomical regions, as illustrated by elicitation of the blink reflex, F wave, and H reflex, and the use of the inching technique. Other methods used to assess special aspects of nerve conduction include the ischemic test and studies of slow-conducting fibers. PMID:6093680

  17. Impaired visual fixation at age 2 years in children born before the 28th week of gestation. Antecedents and correlates in the multi-center ELGAN Study

    PubMed Central

    Phadke, Anuradha; Msall, Michael E; Droste, Patrick; Allred, Elizabeth N; O'Shea, T. Michael; Kuban, Karl; Dammann, Olaf; Leviton, Alan

    2014-01-01

    Background Very little is known about the prevalence, antecedents and correlates of impaired visual fixation in former very preterm newborns. Methods In the multi-center ELGAN Study sample of 1057 infants born before the 28th week of gestation who had a developmental assessment at 2 years corrected age, we identified 73 who were unable to follow an object across the midline. We compared them to the 984 infants who could follow an object across the midline. Results In this sample of very preterm newborns, those who had impaired visual fixation were much more likely than those without impaired visual fixation to have been born after the shortest of gestations (odds ratio = 3.2; 99% confidence interval =1.4, 7.5) and exposed to maternal aspirin (OR: 5.2; 99% CI: 2.2, 12). They were also more likely than their peers to have had prethreshold ROP (OR: 4.1; 99% CI: 1.8, 9.0). At age 2 years, the children with impaired fixation were more likely than others to be unable to walk (even with assistance) (OR: 7.5; 99% CI: 2.2, 26) and have a Mental Development Index more than 3 standard deviations below the mean of a normative sample (OR:3.6; 99% CI: 1.4, 8.2). Conclusion Risk factors for brain and retinal damage, such as very low gestational age, appear to be risk factors for impaired visual fixation. This inference is further supported by the co-occurrence at age 2 years of impaired visual fixation, inability to walk, and a very low Mental Development Index PMID:24938138

  18. Flare, Persistently Active Disease, and Serologically Active Clinically Quiescent Disease in Systemic Lupus Erythematosus: A 2-Year Follow-Up Study

    PubMed Central

    Conti, Fabrizio; Ceccarelli, Fulvia; Perricone, Carlo; Miranda, Francesca; Truglia, Simona; Massaro, Laura; Pacucci, Viviana Antonella; Conti, Virginia; Bartosiewicz, Izabella; Spinelli, Francesca Romana; Alessandri, Cristiano; Valesini, Guido

    2012-01-01

    Objective Several indices have been proposed to assess disease activity in patients with Systemic Lupus Erythematosus (SLE). Recent studies have showed a prevalence of flare between 28–35.3%, persistently active disease (PAD) between 46%–52% and serologically active clinically quiescent (SACQ) disease ranging from 6 to 15%. Our goal was to evaluate the flare, PAD and SACQ rate incidence in a cohort of SLE patients over a 2-year follow-up. Methods We evaluated 394 SLE patients. Flare was defined as an increase in SLEDAI-2K score of ≥4 from the previous visit; PAD was defined as a SLEDAI-2K score of ≥4, on >2 consecutive visits; SACQ was defined as at least a 2-year period without clinical activity and with persistent serologic activity. Results Among the 95 patients eligible for the analysis in 2009, 7 (7.3%) had ≥1 flare episode, whereas 9 (9.4%) had PAD. Similarly, among the 118 patients selected for the analysis in 2010, 6 (5%) had ≥1 flare episode, whereas 16 (13.5%) had PAD. Only 1/45 patient (2.2%) showed SACQ during the follow-up. Conclusion We showed a low incidence of flare, PAD and SACQ in Italian SLE patients compared with previous studies which could be partly explained by ethnic differences. PMID:23029327

  19. Intercostal nerve conduction study in man.

    PubMed Central

    Pradhan, S; Taly, A

    1989-01-01

    A new surface technique for the conduction study of the lower intercostal nerves has been developed and applied to 30 normal subjects. The problem of the short available nerve segment of the intercostal nerves and the bizzare compound motor action potential (CMAP) of inconsistent latency while recording over the intercostal muscles, is overcome by applying recording electrodes over the rectus abdominis muscle and stimulating the nerves at two points at a fair distance away. With the use of multiple recording sites over the rectus abdominis, the motor points for different intercostal nerves were delineated. CMAP of reproducible latencies and waveforms with sharp take-off points were obtained. Conduction velocity of the intercostal nerves could be determined. PMID:2526200

  20. CCL2, CCL18 and sIL-4R in renal, meningeal and pulmonary TB; a 2 year study of patients and contacts.

    PubMed

    Mendez, Armando; Hernandez-Pando, Rogelio; Contreras, Salvador; Aguilar, Diana; Rook, Graham A W

    2011-03-01

    The role of Th2 cytokines and Th2-associated chemokines in tuberculosis (TB) remains controversial, though in Mexico a polymorphism causing increased production of CCL2 is a risk factor. We studied levels of the Th2-associated chemokines CCL2 and CCL18, circulating soluble IL-4 receptors (sIL-4R), IL-4 and the inhibitory splice variant of IL-4 (IL-4δ2) in a cohort of patients with pulmonary TB and their healthy contacts. These were followed for 2 years during which time 10 contacts developed pulmonary TB. Results were compared with measurements made in renal and meningeal TB, and in disease controls with bacterial pneumonias or Dengue fever that have large Th2 components. In these disease controls both chemokines were significantly raised. They were also very significantly raised in all forms of TB, irrespective of age or disease site. Levels of CCL18 were raised least in meningeal TB, and most in pulmonary patients with long histories, when levels were similar to those in disease controls. Levels of CCL2, although also raised in all three forms of TB, were negatively correlated with CCL18. We found that levels of sIL-4R were strikingly reduced in all forms of TB, particularly meningeal. Contacts who progressed could not be distinguished from contacts who remained healthy at 2 years in terms of IL-4, sIL-4R, CCL2 or CCL18. However contacts had raised expression of IL-4δ2 as previously found. These results indicate vigorous and previously unrecorded activity within the Th2 axis, and further investigation is warranted. PMID:21251883

  1. Changes in the frequency of benign focal spikes accompany changes in central information processing speed: a prospective 2-year follow-up study.

    PubMed

    Ebus, S C M; IJff, D M; den Boer, J T; van Hall, M J H; Klinkenberg, S; van der Does, A; Boon, P J; Arends, J B A M; Aldenkamp, A P

    2015-02-01

    We prospectively examined whether changes in the frequency of benign focal spikes accompany changes in cognition. Twenty-six children with benign focal spikes (19 with Rolandic epilepsy) and learning difficulties were examined with repeated 24-hour EEG recordings, three cognitive tests on central information processing speed (CIPS), and questionnaires on cognition and behavior at baseline, 6months, and 2years. Antiepileptic drug changes were allowed when estimated necessary by the treating physician. At baseline, a lower CIPS was correlated with a higher frequency of diurnal interictal epileptiform discharges (IEDs) and with worse academic achievement. At follow-up, there was a significant correlation between changes in CIPS and EEG changes in wakefulness (in the same direction) when the EEG outcome was dichotomized in IED frequency "increased" or "not increased". Behavioral problems were more often observed in patients with higher frequency of IEDs in sleep at baseline and in those with ongoing IEDs compared with those with EEG remission (without or with sporadic IEDs in the recording) at the end of the study period. No changes were observed in the results of the questionnaires. A lower diurnal IED frequency at baseline, lack of serial IEDs, and occurrence of only unilateral IEDs were correlated with a higher chance of EEG remission at 2-year follow-up. Electroencephalography remission could not be predicted from other epilepsy variables except from seizure freedom in the last six months. Our results confirm the nonbenign character of 'benign' focal spikes. Whether an early and stable EEG remission can be achieved through antiepileptic treatment and whether this is of benefit for cognitive development should be examined in prospective placebo-controlled randomized trials. PMID:25546731

  2. Two phase detonation studies conducted in 1971

    NASA Technical Reports Server (NTRS)

    Nicholls, J. A.

    1972-01-01

    A report is presented describing the research conducted on five phases: (1) ignition of fuel drops by a shock wave and passage of a shock wave over a burning drop, (2) the energy release pattern of a two-phase detonation with controlled drop sizes, (3) the attenuation of shock and detonation waves passing over an acoustic liner, (4) experimental and theoretical studies of film detonations, and (5) a simplified analytical model of a rotating two-phase detonation wave in a rocket motor.

  3. Social Development:: 2 Year Olds

    MedlinePlus

    ... Español Text Size Email Print Share Social Development: 2 Year Olds Page Content Article Body By nature, ... probably are acting the same way. At age two, children view the world almost exclusively through their ...

  4. Language Development: 2 Year Olds

    MedlinePlus

    ... Stages Listen Español Text Size Email Print Share Language Development: 2 Year Olds Page Content Article Body ... Pay attention to how he also is using language to describe ideas and information and to express ...

  5. Conducting a pilot study: case study of a novice researcher.

    PubMed

    Doody, Owen; Doody, Catriona M

    Pilot studies play a vital role in health research, but are often misused, mistreated and misrepresented. A well-conducted pilot study with clear aims and objectives within a formal framework ensures methodological rigour, can lead to higher-quality research and scientifically valid work that is publishable and can benefit patients and health service delivery. A pilot study contributes valuable information to assist researchers in the conduct of their study. Conducting a pilot study provides the researcher with the opportunity to develop and enhance the skills necessary before commencing the larger study. By conducting a pilot the researcher obtains preliminary data, can evaluate their data-analysis method and clarify the financial and human resources required. This article presents an overview of pilot studies, why they are conducted, what to consider when reporting pilot studies and the authors' experience of conducting a pilot study. To conduct a successful study, researchers need to develop their skills, choose the right methods and carefully plan for all aspects of the process. PMID:26618678

  6. Bacterial community shift is induced by dynamic environmental parameters in a changing coastal ecosystem (northern Adriatic, northeastern Mediterranean Sea)--a 2-year time-series study.

    PubMed

    Tinta, T; Vojvoda, J; Mozetič, P; Talaber, I; Vodopivec, M; Malfatti, F; Turk, V

    2015-10-01

    The potential link between the microbial dynamics and the environmental parameters was investigated in a semi-enclosed and highly dynamic coastal system (Gulf of Trieste, northern Adriatic Sea, NE Mediterranean Sea). Our comprehensive 2-year time-series study showed that despite the shallowness of this area, there was a significant difference between the surface and the bottom bacterial community structure. The bottom bacterial community was more diverse than the surface one and influenced by sediment re-suspension. The surface seawater temperature had a profound effect on bacterial productivity, while the bacterial community structure was more affected by freshwater-borne nutrients and phytoplankton blooms. Phytoplankton blooms caused an increase of Gammaproteobacteria (Alteromonadaceae, SAR86 and Vibrionaceae) and shift in dominance from SAR11 to Rhodobacteraceae taxon at the surface. Our results propose the importance of the water mass movements as drivers of freshwater-borne nutrients and of allochthonous microbial taxa. This study emphasizes the prediction power based on association networks analyses that are fed with long-term measurements of microbial and environmental parameters. These interaction maps offer valuable insights into the response of marine ecosystem to climate- and anthropogenic-driven stressors. PMID:24903068

  7. Influence of Anti-TNF and Disease Modifying Antirheumatic Drugs Therapy on Pulmonary Forced Vital Capacity Associated to Ankylosing Spondylitis: A 2-Year Follow-Up Observational Study

    PubMed Central

    Rocha-Muñoz, Alberto Daniel; Brambila-Tapia, Aniel Jessica Leticia; Zavala-Cerna, María Guadalupe; Vásquez-Jiménez, José Clemente; De la Cerda-Trujillo, Liliana Faviola; Vázquez-Del Mercado, Mónica; Rodriguez-Jimenez, Norma Alejandra; Díaz-Rizo, Valeria; Díaz-González, Viviana; Cardona-Muñoz, Ernesto German; Dávalos-Rodríguez, Ingrid Patricia; Salazar-Paramo, Mario; Gamez-Nava, Jorge Ivan; Nava-Zavala, Arnulfo Hernan; Gonzalez-Lopez, Laura

    2015-01-01

    Objective. To evaluate the effect of anti-TNF agents plus synthetic disease modifying antirheumatic drugs (DMARDs) versus DMARDs alone for ankylosing spondylitis (AS) with reduced pulmonary function vital capacity (FVC%). Methods. In an observational study, we included AS who had FVC% <80% at baseline. Twenty patients were taking DMARDs and 16 received anti-TNF + DMARDs. Outcome measures: changes in FVC%, BASDAI, BASFI, 6-minute walk test (6MWT), Borg scale after 6MWT, and St. George's Respiratory Questionnaire at 24 months. Results. Both DMARDs and anti-TNF + DMARDs groups had similar baseline values in FVC%. Significant improvement was achieved with anti-TNF + DMARDs in FVC%, at 24 months, when compared to DMARDs alone (P = 0.04). Similarly, patients in anti-TNF + DMARDs group had greater improvement in BASDAI, BASFI, Borg scale, and 6MWT when compared to DMARDs alone. After 2 years of follow-up, 14/16 (87.5%) in the anti-TNF + DMARDs group achieved the primary outcome: FVC% ≥80%, compared with 11/20 (55%) in the DMARDs group (P = 0.04). Conclusions. Patients with anti-TNF + DMARDs had a greater improvement in FVC% and cardiopulmonary scales at 24 months compared with DMARDs. This preliminary study supports the fact that anti-TNF agents may offer additional benefits compared to DMARDs in patients with AS who have reduced FVC%. PMID:26078986

  8. Conductance Studies of Aqueous Succinic Acid

    NASA Astrophysics Data System (ADS)

    Apelblat, Alexander; Barthel, Josef

    1992-03-01

    Conductance measurements of aqueous solutions of succinic acid and of di-sodium succinate were performed from 278.15 to 308.15 K and the limiting conductances λ0 (1/2 Succ2- ) are reported. The Waiden product is independent of temperature: λ0(1/2 Succ2-)*η(T) = 0.503 ± 0.001. The salt conductances closely obey the Onsager limiting law. The evaluation of the equilibrium constants for the primary and secondary steps of dissociation, K1 and K2, and the limiting conductances of the hydrosuccinate ion, λ0(HSucc-), are discussed using the Quint and Viallard conductance equation

  9. Violent Reinjury and Mortality Among Youth Seeking Emergency Department Care for Assault-Related Injury A 2-Year Prospective Cohort Study

    PubMed Central

    Cunningham, Rebecca M.; Carter, Patrick M.; Ranney, Megan; Zimmerman, Marc A.; Blow, Fred C.; Booth, Brenda M.; Goldstick, Jason; Walton, Maureen A.

    2015-01-01

    IMPORTANCE Violence is a leading cause of morbidity and mortality among youth, with more than 700 000 emergency department (ED) visits annually for assault-related injuries. The risk for violent reinjury among high-risk, assault-injured youth is poorly understood. OBJECTIVE To compare recidivism for violent injury and mortality outcomes among drug-using, assault-injured youth (AI group) and drug-using, non–assault-injured control participants (non-AI group) presenting to an urban ED for care. DESIGN, SETTING, AND PARTICIPANTS Participants were enrolled in a prospective cohort study from December 2, 2009, through September 30, 2011, at an urban level I ED and followed up for 24 months. We administered validated measures of violence and substance use and mental health diagnostic interviews and reviewed medical records at baseline and at each point of follow-up (6, 12, 18, and 24 months). EXPOSURE Follow-up over 24 months. MAIN OUTCOMES AND MEASURES Use of ED services for assault or mortality measured from medical record abstraction supplemented with self-report. RESULTS We followed 349 AI and 250 non-AI youth for 24 months. Youth in the AI group had almost twice the risk for a violent injury requiring ED care within 2 years compared with the non-AI group (36.7% vs 22.4%; relative risk [RR], 1.65 [95% CI, 1.25-2.14]; P < .001). Two-year mortality was 0.8%. Poisson regression modeling identified female sex (RR, 1.30 [95% CI, 1.02-1.65]), assault-related injury (RR, 1.57 [95% CI, 1.19-2.04), diagnosis of a drug use disorder (RR, 1.29 [95% CI, 1.01-1.65]), and posttraumatic stress disorder (RR, 1.47 [95% CI, 1.09-1.97]) at the index visit as predictive of ED recidivism or death within 24 months. Parametric survival models demonstrated that assault-related injury (P < .001), diagnosis of posttraumatic stress disorder (P = .008), and diagnosis of a drug use disorder (P = .03) significantly shortened the expected waiting time until the first ED return visit for violence

  10. Comparison of olanzapine long-acting injection and oral olanzapine: a 2-year, randomized, open-label study in outpatients with schizophrenia.

    PubMed

    Detke, Holland C; Weiden, Peter J; Llorca, Pierre-Michel; Choukour, Moutaz; Watson, Susan B; Brunner, Elizabeth; Ascher-Svanum, Haya

    2014-08-01

    We compared long-term treatment effectiveness of monthly olanzapine long-acting injection (LAI) with that of oral olanzapine. Outpatients with 2 or more episodes of psychotic worsening in the past 24 months with Positive and Negative Syndrome Scale total score of lower than 70 were randomized to 405 mg/4 weeks of olanzapine LAI (n = 264) or 10 mg/d of oral olanzapine (n = 260) for 2 years of open-label treatment. Dosing thereafter was flexible (150-405 mg/4 weeks of LAI vs 5-20 mg/d of oral). Primary outcome was time to all-cause discontinuation. At baseline, patients were clinically stable (mean Positive and Negative Syndrome Scale total score of 57). Seventeen percent of patients had been psychiatrically hospitalized in the previous 6 months, and 4.6% were rated nonadherent in the month before study entry. The groups did not differ significantly in median time to all-cause discontinuation (645 days for LAI, 678 days for oral; P = 0.61), discontinuation rate (53.8% for LAI, 51.2% for oral; P = 0.60), or relapse rate (20.1% for LAI, 18.5% for oral; P = 0.66). Postbaseline psychiatric hospitalization rate was low for both groups (7.6% for LAI, 9.2% for oral), but mean hospitalization duration was significantly longer for oral patients (1.80 days [20 for those hospitalized] vs 0.43 days [6 for those hospitalized], P = 0.02). There were no clinically significant group differences in adverse events or safety measures. No post-injection delirium/sedation syndrome events occurred. In conclusion, olanzapine LAI and oral olanzapine were similarly effective and well tolerated for up to 2 years of treatment in patients with schizophrenia. Treatment discontinuation for olanzapine LAI was similar to that of oral olanzapine, despite the 3-hour post-injection observation period and other precautionary procedures related to risk of post-injection delirium/sedation syndrome. PMID:24781441

  11. Working memory arrest in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder: results from a 2-year longitudinal study.

    PubMed

    Andersen, Per N; Skogli, Erik W; Hovik, Kjell T; Geurts, Hilde; Egeland, Jens; Øie, Merete

    2015-05-01

    The aim of this study was to analyse the development of verbal working memory in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder and typically developing children. A total of 34 children with high-functioning autism, 72 children with attention-deficit/hyperactivity disorder and 45 typically developing children (age 9-16 years) were included at baseline and followed up approximately 25 months later. The children were given a letter/number sequencing task to assess verbal working memory. The performance of children with high-functioning autism on verbal working memory did not improve after 2 years, while improvement was observed in children with attention-deficit/hyperactivity disorder and typically developing children. The results indicate a different developmental trajectory for verbal working memory in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder and typically developing children. More research is needed to construct a developmental framework more suitable for children with autism spectrum disorder. PMID:24604922

  12. Violence and Abuse Against Women Who Have Attempted Suicide by Deliberate Self-Poisoning: A 2-Year Follow-Up Study in Iran.

    PubMed

    Hassanian-Moghaddam, Hossein; Zamani, Nasim; Sarjami, Saeedeh

    2016-04-01

    Sources of data about the occurrence of domestic violence are scarce in Iran. The aim of this study was to evaluate the behavioral effects of different types of domestic violence on women who had attempted suicide by deliberate self-poisoning (DSP). A total of 195 women who had attempted suicide by DSP in response to "violence and abuse" were followed up for 2 years. The most common type of violence, as mentioned by the women themselves as the motive of self-poisoning, was physical abuse (92%) followed by verbal abuse (2.1%), multi-abuses (2.1%), emotional abuse (1.6%), and sexual abuse (1.1%). Suicidal ideation and attempt were more common in those who were consulted sometime after they had initially presented to the hospital with DSP or those who had suffered repeated domestic abuse. It was concluded that invention of methods other than the current consultation system is necessary to prevent repeated suicide attempts among abused women in Iran. PMID:25550168

  13. The performance of moss, grass, and 1- and 2-year old spruce needles as bioindicators of contamination: a comparative study at the scale of the Czech Republic.

    PubMed

    Suchara, Ivan; Sucharova, Julie; Hola, Marie; Reimann, Clemens; Boyd, Rognvald; Filzmoser, Peter; Englmaier, Peter

    2011-05-01

    Moss (Pleurozium schreberi), grass (Avenella flexuosa), and 1- and 2-year old spruce (Picea abies) needles were collected over the territory of the Czech Republic at an average sample density of 1 site per 290km(2). The samples were analysed for 39 elements (Ag, Al, As, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga, Hg, K, La, Li, Mg, Mn, Mo, Na, Nd, Ni, Pb, Pr, Rb, S, Sb, Se, Sn, Sr, Th, Tl, U, V, Y and Zn) using ICP-MS and ICP-AES techniques (the major nutrients Ca, K, Mg and Na were not analysed in moss). Moss showed by far the highest element concentrations for most elements. Exceptions were Ba (spruce), Mn (spruce), Mo (grass), Ni (spruce), Rb (grass) and S (grass). Regional distribution maps and spatial trend analysis were used to study the suitability of the four materials as bioindicators of anthropogenic contamination. The highly industrialised areas in the north-west and the far east of the country and several more local contamination sources were indicated in the distribution maps of one or several sample materials. At the scale of the whole country moss was the best indicator of known contamination sources. However, on a more local scale, it appeared that spruce needles were especially well suited for detection of urban contamination. PMID:21421258

  14. A 2-Year Field Study Shows Little Evidence That the Long-Term Planting of Transgenic Insect-Resistant Cotton Affects the Community Structure of Soil Nematodes

    PubMed Central

    Li, Xiaogang; Liu, Biao

    2013-01-01

    Transgenic insect-resistant cotton has been released into the environment for more than a decade in China to effectively control the cotton bollworm (Helicoverpa armigera) and other Lepidoptera. Because of concerns about undesirable ecological side-effects of transgenic crops, it is important to monitor the potential environmental impact of transgenic insect-resistant cotton after commercial release. Our 2-year study included 1 cotton field where non-transgenic cotton had been planted continuously and 2 other cotton fields where transgenic insect-resistant cotton had been planted for different lengths of time since 1997 and since 2002. In 2 consecutive years (2009 and 2010), we took soil samples from 3 cotton fields at 4 different growth stages (seedling, budding, boll-forming and boll-opening stages), collected soil nematodes from soil with the sugar flotation and centrifugation method and identified the soil nematodes to the genus level. The generic composition, individual densities and diversity indices of the soil nematodes did not differ significantly between the 2 transgenic cotton fields and the non-transgenic cotton field, but significant seasonal variation was found in the individual densities of the principal trophic groups and in the diversity indices of the nematodes in all 3 cotton fields. The study used a comparative perspective to monitor the impact of transgenic insect-resistant cotton grown in typical ‘real world’ conditions. The results of the study suggested that more than 10 years of cultivation of transgenic insect-resistant cotton had no significant effects–adverse or otherwise–on soil nematodes. This study provides a theoretical basis for ongoing environmental impact monitoring of transgenic plants. PMID:23613899

  15. The incidence and risk factors for shipping fever in horses transported by air to Hong Kong: Results from a 2-year prospective study.

    PubMed

    Hurley, M J; Riggs, C M; Cogger, N; Rosanowski, S M

    2016-08-01

    A 2 year prospective study was performed between February 2011 and January 2013 to determine the incidence and risk factors for shipping fever (SF) in horses transported by air to Hong Kong (HK). Using a questionnaire, data were collected from professional flying grooms regarding the journey to HK and horses in the shipment. Horses were monitored in quarantine for 2 weeks after arrival in HK, and clinical signs of SF recorded. Poisson and logistic regression models were used to identify risk factors for SF at the horse and shipment levels. The study analysed data from 869 horses on 81 flights arriving from Australia (n = 24), New Zealand (NZ; n = 18), the United Kingdom (UK; n = 33) and the United States of America (USA; n = 6). The incidence risk of SF was 10.8 per 100 horses and the proportion of shipments with at least one horse that developed SF was 49/81 (60%). The study identified that the rate per shipment of SF in shipments of horses originating from NZ, the USA and the UK was 2.40 (95% confidence interval [CI] 1.22-4.71), 2.43 (95% CI 0.66-8.89) and 3.08 (95% CI 1.60-5.93) times the rate of SF compared to Australia. Shipments arriving in HK during March and May were 5.61 (95% CI 1.55-20.31) and 4.51 (95% CI 1.43-14.26) times more likely to contain horses that developed SF compared to shipments arriving in January. The identification of these risk factors and the recognition of at-risk shipments will help focus attention on preventative strategies. PMID:27387724

  16. Emotional Development: 2 Year Olds

    MedlinePlus

    ... Español Text Size Email Print Share Emotional Development: 2 Year Olds Page Content Article Body It’s so ... to follow the ups and downs of a two-year-old. One moment he’s beaming and friendly; ...

  17. A Multicenter, Single-Blind Randomized, Controlled Study of a Volumizing Hyaluronic Acid Filler for Midface Volume Deficit: Patient-Reported Outcomes at 2 Years

    PubMed Central

    Few, Julius; Cox, Sue Ellen; Paradkar-Mitragotri, Deepali; Murphy, Diane K.

    2015-01-01

    Background Juvéderm Voluma XC is a volumizing hyaluronic acid filler used for correction of age-related midface volume deficit (MVD). Objectives The effectiveness of Juvéderm Voluma XC was examined from the patient perspective. Methods Patients with moderate to severe age-related MVD (N = 235) received Juvéderm Voluma XC. At quarterly follow-up visits for 2 years, patients rated treatment outcomes on the Global Aesthetic Improvement Scale (GAIS), overall satisfaction with facial appearance, satisfaction with midfacial regions, achievement of treatment goal, Look and Feel of the Midface (LAFM), and Self-Perception of Age (SPA). Patients recorded treatment-site responses in 30-day diaries. Results At 6 months and 2 years after treatment, 92.8% and 79.0% of patients, respectively, rated their cheek volume as improved/much improved on the GAIS. Improvement in satisfaction with facial appearance was noted by 89.8% of patients at 6 months and 75.8% at 2 years. Increased satisfaction with outer and lower cheek areas and cheek-bone projection and clinically significant improvements in LAFM were noted through month 24. Treatment goals were achieved by 67.8% of patients at 6 months and 49.0% at 2 years. Patients reported looking, on average, 5 years younger at 6 months and 3 years younger at 2 years. The most common treatment site responses were tenderness, swelling, firmness, and lumps/bumps; most were mild to moderate in severity and lasted ≤2 weeks. Conclusions Juvéderm Voluma XC for age-related MVD is effective and well-tolerated from the patient perspective, with results lasting up to 2 years. Level of Evidence 4 Therapeutic PMID:25964628

  18. Revision Total Hip Arthroplasty Using Tantalum Augment in Patients with Paprosky III or IV Acetabular Bone Defects: A Minimum 2-year Follow Up Study

    PubMed Central

    Jeong, Min; Kim, Hyung-Joo; Lim, Seung-Jae; Moon, Young-Wan

    2016-01-01

    Purpose The purpose of this study is to report the short-term outcomes of revision total hip arthroplasty (THA) using tantalum augments in patients with severe acetabular bone defects. Materials and Methods We retrospectively analyzed 15 revision THAs performed in 15 patients using tantalum augments between June 2010 and December 2013. Acetabular bone defects were Paprosky type IIIA in 7 hips, type IIIB in 7, and type IV in 1. The causes of revision surgery were aseptic loosening in 12 hips and deep infection in 3. Revisions were first in 1 hip, second in 3, and third in 11. Six patients were male and 9 female with a mean age of 59 years (range, 48-75 years). Mean follow-up was 29 months (range, 24-48 months). Results Mean Harris hip score was improved from 34 points (range, 12-54 points) preoperatively to 84 points (range, 38-90 points) at final follow-up. On the final follow-up radiographs, there were 12 hips (80.0%) with stable fixation of the acetabular cup, 2 (13.3%) with secondary stability after mild acetabular protrusion, and 1 (6.7%) with radiolucency around the acetabular cup without mechanical symptoms. Complications included one patient with acute hematogenous infection managed by surgical debridement and long-term antibiotic therapy. There were no cases with nerve palsy or dislocation during the follow-up period. Conclusion The present study showed satisfactory clinical and radiographic outcomes of revision THA using tantalum augments due to severe acetabular bone defects of Paprosky type III or IV at a minimum follow-up of 2 years. PMID:27536651

  19. Comparison of one-level microendoscopy laminoforaminotomy and cervical arthroplasty in cervical spondylotic radiculopathy: a minimum 2-year follow-up study

    PubMed Central

    2013-01-01

    Background This study aims to compare the perioperative parameters and clinical results between microendoscopy laminoforaminotomy (MELF) and cervical arthroplasty (CA) in the treatment of one-level cervical spondylotic radiculopathy in a retrospective study. Methods From 2003 to 2007, a total of 97 patients with one-level cervical spondylotic radiculopathy were treated. Forty-five patients underwent CA. Fifty-two patients underwent MELF. Patient demographics and operative data were collected with a minimum 2-year follow-up. Perioperative parameters were compared. Clinical assessment in terms of neck disability index (NDI), short form (SF)-36, and visual analogue scale (VAS) of arm pain and neck pain was performed prior to surgery and at 1.5, 3, 6, 12, and 24 months after surgery. Results Fluoroscopy time (CA, 60.3 s; MELF, 12.1 s; P < 0.01) and surgical time (CA, 95.1 min; MELF, 24.0 min; P < 0.01) were significantly longer in the CA cases. Shorter hospitalized days (CA, 1.1 days; MELF, 0.13 days; P < 0.01) and less estimated blood loss (EBL; CA, 75.8 ml; MELF, 31.9 ml; P < 0.01) were observed in the MELF group. Both CA and MELF groups showed significant improvement in NDI, VAS of neck pain and arm pain, and SF-36 (P < 0.05 for each) at 1.5, 3, 6, 12, and 24 months after surgery, but there was no significant difference between them (P > 0.05). Conclusions As alternatives of anterior cervical decompression and fusion (ACDF), both CA and MELF can produce satisfactory clinical outcomes. MELF has the additional benefits of less blood loss, less surgical time, less X-ray time, and shorter hospital stay. PMID:24341633

  20. Conductance Studies on Aqueous Citric Acid

    NASA Astrophysics Data System (ADS)

    Apelblat, Alexander; Barthel, Josef

    1991-02-01

    Conductance measurements of citric acid and neutral citrates (tri-lithium citrate, tri-sodium citrate and tri-potassium citrate) were performed in water at 278.15 to 308.15 K. The equilibrium constants for the primary and secondary steps of dissociation, Kx and K2, and the limiting conductances, λ0(H2Cit-), λ°(1/2 HCit2-), and λ0(1/3 Cit3-) are reported as a function of temperature. They are obtained by application of the Quint and Viallard conductance equation. The enthalpies of dissociation are estimated.

  1. Dasatinib in Imatinib-Resistant or Imatinib-Intolerant Chronic Myeloid Leukemia in Blast Phase After 2 Years of Follow-Up in a Phase 3 Study

    PubMed Central

    Saglio, Giuseppe; Hochhaus, Andreas; Goh, Yeow Tee; Masszi, Tamas; Pasquini, Ricardo; Maloisel, Frederic; Erben, Philipp; Cortes, Jorge; Paquette, Ronald; Bradley-Garelik, M. Brigid; Zhu, Chao; Dombret, Herve

    2016-01-01

    BACKGROUND In a phase 3 study, the authors assessed the effects of dasatinib at doses of 140 mg once daily and 70 mg twice daily in patients who had either chronic myeloid leukemia (CML) in advanced phases or Philadelphia chromosome-positive acute lymphoblastic leukemia and were resistant or intolerant to imatinib. In the current report, the results for patients with CML in blast phase after 2 years of follow-up are reported. METHODS Patients were stratified according to whether they had CML in myeloid blast phase (MBP-CML) or in lymphoid blast phase (LBP-CML) and were randomized (1:1) within each stratum to receive either oral dasatinib 140 mg once daily or 70 mg twice daily. RESULTS In patients with MBP-CML, the major hematologic response rate was 28% for both regimens; and, in patients with LBP-CML, the major hematologic response rate was 42% for once-daily dasatinib and 32% for twice-daily dasatinib. The major cytogenetic response rates were 25% for once-daily dasatinib and 28% for twice-daily dasatinib in patients with MBP-CML, and the respective rates in patients with LBP-CML were 50% and 40%. The overall survival rate at 24 months was 24% for once-daily dasatinib and 28% for twice-daily dasatinib in patients with MBP-CML, and the respective values in patients with LBP-CML were 21% and 16%. Adverse events indicated a trend toward improved tolerability for the once-daily regimen. CONCLUSIONS The current results suggested that dasatinib 140 mg once daily had similar efficacy and improved tolerability relative to the 70-mg twice-daily regimen in patients with imatinib-resistant, blast phase CML. PMID:20564086

  2. Scaling up family medicine training in Gezira, Sudan – a 2-year in-service master programme using modern information and communication technology: a survey study

    PubMed Central

    2014-01-01

    Background In 2010 the Gezira Family Medicine Project (GFMP) was initiated in Gezira state, Sudan, designed as an in-service training model. The project is a collaboration project between the University of Gezira, which aims to provide a 2-year master’s programme in family medicine for practicing doctors, and the Ministry of Health, which facilitates service provision and funds the training programme. This paper presents the programme, the teaching environment, and the first batch of candidates enrolled. Methods In this study a self-administered questionnaire was used to collect baseline data at the start of the project from doctors who joined the programme. A checklist was also used to assess the health centres where they work. A total of 188 out of 207 doctors responded (91%), while data were gathered from all 158 health centres (100%) staffed by the programme candidates. Results The Gezira model of in-service family medicine training has succeeded in recruiting 207 candidates in its first batch, providing health services in 158 centres, of which 84 had never been served by a doctor before. The curriculum is community oriented. The mean age of doctors was 32.5 years, 57% were males, and 32% were graduates from the University of Gezira. Respondents stated high confidence in practicing some skills such as asthma management and post-abortion uterine evacuation. They were least confident in other skills such as managing depression or inserting an intrauterine device. The majority of health centres was poorly equipped for management of noncommunicable diseases, as only 10% had an electrocardiography machine (ECG), 5% had spirometer, and 1% had a defibrillator. Conclusions The Gezira model has responded to local health system needs. Use of modern information and communication technology is used to facilitate both health service provision and training. The GFMP represents an example of a large-volume scaling-up programme of family medicine in Africa. PMID:24443978

  3. Structural and Electrical Study of Conducting Polymers

    NASA Astrophysics Data System (ADS)

    Shaktawat, Vinodini; Dixit, Manasvi; Saxena, N. S.; Sharma, Kananbala

    2010-06-01

    Pure and oxalic acid doped conducting polymers (polyaniline and polypyrrole) were chemically synthesized using ammonium persulfate (APS) as an oxidant. These samples were characterized through Scanning Electron Microscopy (SEM), which provides information about the surface topography of polymers. I-V characteristics have been recorded at room temperature as well as in the temperature range from 313 K to 463 K. So obtained characteristic curves were found to be linear. Temperature dependence of conductivity suggests a semiconducting nature in polyaniline samples with increase in temperature, whereas oxalic acid doped polypyrrole sample suggests a transition from semiconducting to metallic nature with the increase of temperature.

  4. Neuroscience Investigations: An Overview of Studies Conducted

    NASA Technical Reports Server (NTRS)

    Reschke, Millard F.

    1999-01-01

    The neural processes that mediate human spatial orientation and adaptive changes occurring in response to the sensory rearrangement encountered during orbital flight are primarily studied through second and third order responses. In the Extended Duration Orbiter Medical Project (EDOMP) neuroscience investigations, the following were measured: (1) eye movements during acquisition of either static or moving visual targets, (2) postural and locomotor responses provoked by unexpected movement of the support surface, changes in the interaction of visual, proprioceptive, and vestibular information, changes in the major postural muscles via descending pathways, or changes in locomotor pathways, and (3) verbal reports of perceived self-orientation and self-motion which enhance and complement conclusions drawn from the analysis of oculomotor, postural, and locomotor responses. In spaceflight operations, spatial orientation can be defined as situational awareness, where crew member perception of attitude, position, or motion of the spacecraft or other objects in three-dimensional space, including orientation of one's own body, is congruent with actual physical events. Perception of spatial orientation is determined by integrating information from several sensory modalities. This involves higher levels of processing within the central nervous system that control eye movements, locomotion, and stable posture. Spaceflight operational problems occur when responses to the incorrectly perceived spatial orientation are compensatory in nature. Neuroscience investigations were conducted in conjunction with U. S. Space Shuttle flights to evaluate possible changes in the ability of an astronaut to land the Shuttle or effectively perform an emergency post-landing egress following microgravity adaptation during space flights of variable length. While the results of various sensory motor and spatial orientation tests could have an impact on future space flights, our knowledge of

  5. Factors Predicting Patient Dissatisfaction 2 Years After Discectomy for Lumbar Disc Herniation in a Chinese Older Cohort: A Prospective Study of 843 Cases at a Single Institution.

    PubMed

    Wang, Hui; Zhang, Di; Ma, Lei; Shen, Yong; Ding, Wenyuan

    2015-10-01

    We aim to identify factors predicting patient dissatisfaction 2 years after discectomy for lumbar disc herniation (LDH) in a Chinese older cohort. Preoperative and 2-year follow-up data for 843 patients were analyzed. After 2 years of discectomy, the patients rated their satisfaction by Patient Satisfaction Index (PSI), with response of 1 or 2 defining satisfaction and a PSI response of 3 or 4 defining dissatisfaction. Associations between perioperative variables and satisfaction with the results of surgery were examined in univariate and multivariate analysis. Six hundred fifty-seven patients had a PSI of 1 or 2 and were enrolled as satisfied group, 186 patients had a PSI of 3 or 4 and were enrolled as dissatisfied group. At baseline, no significant differences were found between the 2 groups in age, occupation, Oswestry Disability Index (ODI), Visual Analog Scale (VAS)-leg, and VAS-back. Compared to satisfied group, dissatisfied group had a significantly higher BMI and a higher incidence of depression. Two years after discectomy, no significant differences were found between the 2 groups in decrease of ODI, decrease of VAS-back, decrease of VAS-leg, surgery complications. Compared to satisfied group, dissatisfied group experienced higher incidence of symptom recurrence and depression. Logistic regression analysis showed that obesity, pre- and postoperative depression, symptom recurrence were independently associated with patient dissatisfaction 2 years after discectomy.I n conclusion, more than 70% patients expressed satisfaction with discectomy for LDH. Two factors could predict patient dissatisfaction and be assessed before surgery: obesity and preoperative depression. Symptom recurrence and postoperative depression are also associated with diminished patient satisfaction. PMID:26448005

  6. Thermal and electrical contact conductance studies

    NASA Technical Reports Server (NTRS)

    Vansciver, S. W.; Nilles, M.

    1985-01-01

    Prediction of electrical and thermal contact resistance for pressed, nominally flat contacts is complicated by the large number of variables which influence contact formation. This is reflected in experimental results as a wide variation in contact resistances, spanning up to six orders of magnitude. A series of experiments were performed to observe the effects of oxidation and surface roughness on contact resistance. Electrical contact resistance and thermal contact conductance from 4 to 290 K on OFHC Cu contacts are reported. Electrical contact resistance was measured with a 4-wire DC technique. Thermal contact conductance was determined by steady-state longitudinal heat flow. Corrections for the bulk contribution ot the overall measured resistance were made, with the remaining resistance due solely to the presence of the contact.

  7. Electrochemical corrosion studies in low conductivity propellants

    NASA Technical Reports Server (NTRS)

    Blue, G. D.; Moran, C. M.; Distefano, S.

    1986-01-01

    The Jet Propulsion Laboratory is investigating the possibility of developing advanced electrochemical techniques as accelerated compatibility tests for metal/propellant systems which overcome the problems associated with the low conductivity of the liquid propellants (e.g., hydrazines, nitrogen tetroxide). Both DC techniques and AC electrochemical impedance spectroscopy are being evaluated. Progress has been made in experiments involving stainless steel with hydrazine and nitrogen tetroxide propellants.

  8. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study... conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date of... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Conduct of a study. 160.130...

  9. 40 CFR 160.130 - Conduct of a study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... LABORATORY PRACTICE STANDARDS Protocol for and Conduct of a Study § 160.130 Conduct of a study. (a) The study... conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and date of... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Conduct of a study. 160.130...

  10. Gas release and conductivity modification studies

    NASA Technical Reports Server (NTRS)

    Linson, L. M.; Baxter, D. C.

    1979-01-01

    The behavior of gas clouds produced by releases from orbital velocity in either a point release or venting mode is described by the modification of snowplow equations valid in an intermediate altitude regime. Quantitative estimates are produced for the time dependence of the radius of the cloud, the average internal energy, the translational velocity, and the distance traveled. The dependence of these quantities on the assumed density profile, the internal energy of the gas, and the ratio of specific heats is examined. The new feature is the inclusion of the effect of the large orbital velocity. The resulting gas cloud models are used to calculate the characteristics of the field line integrated Pedersen conductivity enhancements that would be produced by the release of barium thermite at orbital velocity in either the point release or venting modes as a function of release altitude and chemical payload weight.

  11. Etiological Role and Repeated Infections of Sapovirus among Children Aged Less than 2 Years in a Cohort Study in a Peri-urban Community of Peru.

    PubMed

    Liu, Xiaofang; Jahuira, Helena; Gilman, Robert H; Alva, Alicia; Cabrera, Lilia; Okamoto, Michiko; Xu, Hang; Windle, Henry J; Kelleher, Dermot; Varela, Marco; Verastegui, Manuela; Calderon, Maritza; Sanchez, Gerardo; Sarabia, Vanessa; Ballard, Sarah B; Bern, Caryn; Mayta, Holger; Crabtree, Jean E; Cama, Vitaliano; Saito, Mayuko; Oshitani, Hitoshi

    2016-06-01

    Human sapovirus has been shown to be one of the most important etiologies in pediatric patients with acute diarrhea. However, very limited data are available about the causative roles and epidemiology of sapovirus in community settings. A nested matched case-control study within a birth cohort study of acute diarrhea in a peri-urban community in Peru from 2007 to 2010 was conducted to investigate the attributable fraction (AF) and genetic diversity of sapovirus. By quantitative reverse transcription-real-time PCR (qPCR) sapovirus was detected in 12.4% (37/299) of diarrheal and 5.7% (17/300) of nondiarrheal stools (P = 0.004). The sapovirus AF (7.1%) was higher in the second year (13.2%) than in the first year (1.4%) of life of children. Ten known genotypes and one novel cluster (n = 5) within four genogroups (GI, GII, GIV, and GV) were identified by phylogenetic analysis of a partial VP1 gene. Further sequence analysis of the full VP1 gene revealed a possible novel genotype, tentatively named GII.8. Notably, symptomatic reinfections with different genotypes within the same (n = 3) or different (n = 5) genogroups were observed in eight children. Sapovirus exhibited a high attributable burden for acute gastroenteritis, especially in the second year of life, of children in a Peruvian community. Further large-scale studies are needed to understand better the global burden, genetic diversity, and repeated infections of sapovirus. PMID:27076657

  12. Practical challenges in conducting respiratory studies

    PubMed Central

    Hake, Sanjay D.; Patil, Mahesh L.; Shah, Tapankumar M.; Gokhale, Partha M.; Suvarna, Viraj

    2015-01-01

    Respiratory studies are complex on account of specific therapeutic knowledge that is needed and various instruments that are used for the management of this condition. Monitoring a respiratory study requires knowledge of the specific disease and associated guidelines. The intent of this article is to help clinical research professionals understand the technicalities, challenges, and the nuances of performing respiratory studies. PMID:25657898

  13. New Walking and Cycling Routes and Increased Physical Activity: One- and 2-Year Findings From the UK iConnect Study

    PubMed Central

    Goodman, Anna; Sahlqvist, Shannon; Ogilvie, David

    2014-01-01

    Objectives. We evaluated the effects of providing new high-quality, traffic-free routes for walking and cycling on overall levels of walking, cycling, and physical activity. Methods. 1796 adult residents in 3 UK municipalities completed postal questionnaires at baseline (2010) and 1-year follow-up (2011), after the construction of the new infrastructure. 1465 adults completed questionnaires at baseline and 2-year follow-up (2012). Transport network distance from home to infrastructure defined intervention exposure and provided a basis for controlled comparisons. Results. Living nearer the infrastructure did not predict changes in activity levels at 1-year follow-up but did predict increases in activity at 2 years relative to those living farther away (15.3 additional minutes/week walking and cycling per km nearer; 12.5 additional minutes/week of total physical activity). The effects were larger among participants with no car. Conclusions. These new local routes may mainly have displaced walking or cycling trips in the short term but generated new trips in the longer term, particularly among those unable to access more distant destinations by car. These findings support the potential for walking and cycling infrastructure to promote physical activity. PMID:25033133

  14. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The...

  15. 18 CFR 5.15 - Conduct of studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The...

  16. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Conduct of a study. 792.130 Section 792.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be...

  17. 40 CFR 792.130 - Conduct of a study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study,...

  18. Losing Control: Conducting Studies with Comparison Groups

    ERIC Educational Resources Information Center

    Norton, Jan

    2006-01-01

    Studies in education often report the differences between participants' and non-participants' test scores, course grades, retention, and other criteria. When participants' average performance is higher, it can be difficult to attribute the improvements to participation. Comparing participants and non-participants on other measures can strengthen…

  19. Conductivity and electrical studies of plasticized carboxymethyl cellulose based proton conducting solid biopolymer electrolytes

    NASA Astrophysics Data System (ADS)

    Isa, M. I. N.; Noor, N. A. M.

    2015-12-01

    In this paper, a proton conducting solid biopolymer electrolytes (SBE) comprises of carboxymethyl cellulose (CMC) as polymer host, ammonium thiocyanate (NH4SCN) as doping salt and ethylene carbonate (EC) as plasticizer has been prepared via solution casting technique. Electrical Impedance Spectroscopy (EIS) was carried out to study the conductivity and electrical properties of plasticized CMC-NH4SCN SBE system over a wide range of frequency between 50 Hz and 1 MHz at temperature range of 303 to 353 K. Upon addition of plasticizer into CMC-NH4SCN SBE system, the conductivity increased from 10-5 to 10-2 Scm-1. The highest conductivity was obtained by the electrolyte containing 10 wt.% of EC. The conductivity of plasticized CMC-NH4SCN SBE system by various temperatures obeyed Arrhenius law where the ionic conductivity increased as the temperature increased. The activation energy, Ea was found to decrease with enhancement of EC concentration. Dielectric studies for the highest conductivity electrolyte obeyed non-Debye behavior. The conduction mechanism for the highest conductivity electrolyte was determined by employing Jonsher's universal power law and thus, can be represented by the quantum mechanical tunneling (QMT) model.

  20. Effects of sediment dredging on nitrogen cycling in Lake Taihu, China: Insight from mass balance based on a 2-year field study.

    PubMed

    Yu, Juhua; Fan, Chengxin; Zhong, Jicheng; Zhang, Lu; Zhang, Lei; Wang, Changhui; Yao, Xiaolong

    2016-02-01

    Sediment dredging can permanently remove pollutants from an aquatic ecosystem, which is considered an effective approach to aquatic ecosystem restoration. In this work, a 2-year field simulation test was carried out to investigate the effect of dredging on nitrogen cycling across the sediment-water interface (SWI) in Lake Taihu, China. The results showed that simulated dredging applied to an area rich in total organic carbon (TOC) and total nitrogen (TN) slightly reduced the NH4(+)-N release from sediments while temporarily enhanced the NH4(+)-N release in an area with lower TOC and/or TN (in the first 180 days), although the application had a limited effect on the fluxes of NO2(-)-N and NO3(-)-N in both areas. Further analysis indicated that dredging induced decreases in nitrification, denitrification, and anaerobic ammonium oxidation (anammox) in sediments, notably by 76.9, 49.0, and 89.9%, respectively, in the TOC and/or TN-rich area. Therefore, dredging slowed down nitrogen cycling rates in sediments but did not increase N loading to overlying water. The main reason for the above phenomenon could be attributed to the removal of the surface sediments enriched with more TOC and/or TN (compared with the bottom sediments). Overall, to minimize internal N pollution, dredging may be more applicable to nutrient-rich sediments. PMID:26499196

  1. Serum levels of osteoprotegerin and receptor activator of nuclear factor -κB ligand in children with early juvenile idiopathic arthritis: a 2-year prospective controlled study

    PubMed Central

    2010-01-01

    Background The clinical relevance of observations of serum levels of osteoprotegerin (OPG) and receptor activator of nuclear factor -κB ligand (RANKL) in juvenile idiopathic arthritis (JIA) is not clear. To elucidate the potential role of OPG and RANKL in JIA we determined serum levels of OPG and RANKL in patients with early JIA compared to healthy children, and prospectively explored changes in relation to radiographic score, bone and lean mass, severity of the disease, and treatment. Methods Ninety children with early oligoarticular or polyarticular JIA (ages 6-18 years; mean disease duration 19.4 months) and 90 healthy children individually matched for age, sex, race, and county of residence, were examined at baseline and 2-year follow-up. OPG and RANKL were quantified by enzyme-immunoassay. Data were analyzed with the use of t-tests, ANOVA, and multiple regression analyses. Results Serum OPG was significantly lower in patients than controls at baseline, and there was a trend towards higher RANKL and a lower OPG/RANKL ratio. Patients with polyarthritis had significantly higher increments in RANKL from baseline to follow-up, compared to patients with oligoarthritis. RANKL was a significant negative predictor for increments in total body lean mass. Patients who were receiving corticosteroids (CS) or disease-modifying antirheumatic drugs (DMARDs) at follow-up had higher OPG/RANKL ratio compared with patients who did not receive this medication. Conclusions The data supports that levels of OPG are lower in patients with JIA compared to healthy children, and higher levels of RANKL is associated with more serious disease. RANKL was a significant negative predictor of lean mass in patients with JIA. The OPG/RANKL ratio was higher in patients on DMARDs or CS treatment. PMID:21134287

  2. The use of oxytocin in liquid semen doses to reduce seasonal fluctuations in the reproductive performance of sows and improve litter parameters--a 2-year study.

    PubMed

    Duziński, Kamil; Knecht, Damian; Srodoń, Sebastian

    2014-04-01

    The objective of the present research was to eliminate seasonal fluctuations in year-round reproductive performance of sows and to improve litter parameters by administration of oxytocin into liquid semen insemination doses. A 2-year experiment was performed on crossbreed sows, Polish Large White × Polish Landrace, which were partitioned into two groups: control, insemination without any modification with 100 mL semen doses and oxytocin, insemination with 100 mL semen doses to which 5 IU of oxytocin was added just before insemination. A total of 10,486 inseminations were made. The farrowing rate and obtained litter parameters, including the effect of season, were analyzed. For each litter, the following factors were defined: average litter size, percentage of fetal death and mummified piglets, average piglet birth weight, percentage of piglet mortality, fecundity index, average number of piglets weaned, weaned piglet weight, and daily gain. Sows presented a positive reaction to the experimental factor. A statistically higher farrowing rate for oxytocin group in summer and autumn seasons was confirmed (P ≤ 0.01). Regardless of the season, a higher average litter size was observed in the oxytocin group with the most evident differences for winter, spring (P ≤ 0.01), and summer (P ≤ 0.05). The effect of oxytocin on the percentage of fetal death and mummified piglets born was not confirmed statistically except for winter. Analyzing the fecundity index, higher values were obtained for the oxytocin group in all seasons (P ≤ 0.01), including the lowest difference between groups for winter (51.43) and the highest for summer (100.61). A higher average birth piglet weight and weaned piglet weight were recorded for the oxytocin group in all seasons. The highest differences in birth piglet weight between groups were noted for spring (0.22 kg; P ≤ 0.01) and winter (0.17 kg; P ≤ 0.05) and in weaned piglet weight for winter and spring (0.58 kg and 0.52 kg; for

  3. Decrease in self-esteem mediates the association between symptoms of social phobia and depression in middle adolescence in a sex-specific manner: a 2-year follow-up of a prospective population cohort study

    PubMed Central

    2014-01-01

    Background Social phobia and depression are common, highly comorbid disorders in middle adolescence. The mechanism underlying this comorbidity, however, is unclear. Decrease in self-esteem caused by the initial disorder might play a decisive role in the development of the subsequent disorder. The present study aimed to determine whether the association between symptoms of social phobia and depression is mediated by decrease in self-esteem in mid-adolescent girls and boys. Methods As a part of the prospective Adolescent Mental Health Cohort (AMCH), subjects of this study were 9th grade pupils (mean age, 15.5) responding to a survey conducted in 2002–2003 (T1) and to a 2-year follow-up survey in 2004–2005 (T2) (N = 2070, mean age 17.6 years, 54.5% girls). Results Symptoms of social phobia without symptoms of depression at age 15 and symptoms of depression at age 17 were associated only among boys, and this association was mediated by decrease in self-esteem. Symptoms of depression without symptoms of social phobia at age 15 and symptoms of social phobia at age 17 were associated only among girls, and this association was partially mediated by decrease in self-esteem. Conclusions Decrease in self-esteem plays a decisive role in the association between social phobia and depression. Self-esteem should be a key focus in interventions for adolescents suffering from social phobia or depression. Efficient intervention for the first disorder might help to prevent the decline in self-esteem and thus the incidence of the subsequent disorder. These findings are based on a sample of Finnish adolescents and should be confirmed in other jurisdictions or in more ethnically diverse samples. PMID:24641987

  4. French multicenter phase III randomized study testing concurrent twice-a-day radiotherapy and cisplatin/5-fluorouracil chemotherapy (BiRCF) in unresectable pharyngeal carcinoma: Results at 2 years (FNCLCC-GORTEC)

    SciTech Connect

    Bensadoun, Rene-Jean . E-mail: rene-jean.bensadoun@nice.fnclcc.fr; Benezery, Karen; Dassonville, Olivier; Magne, Nicolas; Poissonnet, Gilles; Ramaioli, Alain; Lemanski, Claire; Bourdin, Sylvain; Tortochaux, Jacques; Peyrade, Frederic; Marcy, Pierre-Yves; Chamorey, Emmanuel Phar; Vallicioni, Jacques; Seng Hang; Alzieu, Claude; Gery, Bernard; Chauvel, Pierre; Schneider, Maurice; Santini, Jose; Demard, Francois; Calais, Gilles

    2006-03-15

    Background: Unresectable carcinomas of the oropharynx and hypopharynx still have a poor long-term prognosis. Following a previous phase II study, this phase III multicenter trial was conducted between November 1997 and March 2002. Methods: Nontreated, strictly unresectable cases were eligible. Twice-daily radiation: two fractions of 1.2 Gy/day, 5 days per week, with no split (D1{sup {yields}}D46). Total tumor doses: 80.4 Gy/46 day (oropharynx), 75.6 Gy/44 day (hypopharynx). Chemotherapy (arm B): Cisplatin 100 mg/m{sup 2} (D1, D22, D43); 5FU, continuous infusion (D1{sup {yields}}D5), 750 mg/m{sup 2}/day cycle 1; 430 mg/m{sup 2}/day cycles 2 and 3. Results: A total of 163 evaluable patients. Grade 3-4 acute mucositis 82.6% arm B/69.5% arm A (NS); Grade 3-4 neutropenia 33.3% arm B/2.4% arm A (p < 0.05). Enteral nutrition through gastrostomy tube was more frequent in arm B before treatment and at 6 months (p < 0.01). At 24 months, overall survival (OS), disease-free survival (DFS), and specific survival (SS) were significantly better in arm B. OS: 37.8% arm B vs. 20.1% arm A (p = 0.038); DFS: 48.2% vs. 25.2% (p = 0.002); SS: 44.5% vs. 30.2% (p 0.021). No significant difference between the two arms in the amount of side effects at 1 and 2 years. Conclusion: For these unresectable cases, chemoradiation provides better outcome than radiation alone, even with an 'aggressive' dose-intensity radiotherapy schedule.

  5. Predictors (0-10 Months) of Psychopathology at Age 1 1/2 Years--A General Population Study in the Copenhagen Child Cohort CCC 2000

    ERIC Educational Resources Information Center

    Skovgaard, A. M.; Olsen, E. M.; Christiansen, E.; Houmann, T.; Landorph, S. L.; Jorgensen, T.

    2008-01-01

    Background: Epidemiological studies of mental health problems in the first years of life are few. This study aims to investigate infancy predictors of psychopathology in the second year of life. Methods: A random general population sample of 210 children from the Copenhagen Child Birth Cohort CCC 2000 was investigated by data from National Danish…

  6. Working Memory Arrest in Children with High-Functioning Autism Compared to Children with Attention-Deficit/Hyperactivity Disorder: Results from a 2-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Andersen, Per N.; Skogli, Erik W.; Hovik, Kjell T.; Geurts, Hilde; Egeland, Jens; Øie, Merete

    2015-01-01

    The aim of this study was to analyse the development of verbal working memory in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder and typically developing children. A total of 34 children with high-functioning autism, 72 children with attention-deficit/hyperactivity disorder and 45 typically…

  7. Prospective Analysis of a New Bone Graft in Lumbar Interbody Fusion: Results of a 2- Year Prospective Clinical and Radiological Study

    PubMed Central

    Raskin, Yannic

    2015-01-01

    Background This study examined the efficacy and safety of bone graft material ABM/P-15 (iFACTOR) for use in posterior lumbar interbody fusion. ABM/P-15 has been used safely for more than a decade in dental applications. Methods Forty patients underwent PLIF surgery, with each patient as control. Assessments up to 24 months included radiographs, CT scan, VAS, and ODI. Primary success criteria were fusion and safety. Results Intra-cage bridging bone occurred earlier with ABM/P-15 than autograft (97.73% vs. 59.09% at 6 months). On average pain decreased 29 points and function improved 43 points. Radio dense material outside the disk space occurred more frequently with ABM/P-15 than autograft, without clinical consequence. Conclusions This study suggests that ABM/P-15 has equal or greater efficacy at 6 and 12 months. Pain improvements exceeded success criteria at all time points. Functional improvement exceeded success criteria at all time points. Clinical Relevance This study explores the safety and efficacy of an osteobiologic peptide enhanced bone graft material as a viable alternative to autograft and its attendant risks. PMID:25709887

  8. Efficacy and safety of finasteride therapy for benign prostatic hyperplasia: results of a 2-year randomized controlled trial (the PROSPECT study). PROscar Safety Plus Efficacy Canadian Two year Study.

    PubMed Central

    Nickel, J C; Fradet, Y; Boake, R C; Pommerville, P J; Perreault, J P; Afridi, S K; Elhilali, M M

    1996-01-01

    OBJECTIVE: To evaluate the efficacy and safety of 2 years' treatment of moderate benign prostatic hyperplasia (BPH) with finasteride. DESIGN: Double-blind, parallel-group, placebo-controlled, multicentre, prospective randomized study. SETTING: Outpatient care in 28 centres across Canada. PARTICIPANTS: Men aged 45 to 80, in good health, with moderate BPH and no evidence of prostate cancer. A total of 613 men were entered into the study; 472 completed the 2 years of treatment. INTERVENTION: After 1 month of receiving a placebo (run-in period), patients were given either finasteride (5 mg/d) or a placebo for 2 years. OUTCOME MEASURES: Efficacy: changes from baseline in BPH symptom scores, maximum urinary flow rates and prostate volume. Safety: onset, course and resolution of all adverse events during the treatment period. RESULTS: In the efficacy analyses the mean BPH symptom scores decreased 2.1 points (from 15.8 to 13.7) in the finasteride group, as compared with a decrease of 0.7 points (from 16.6 to 15.9) in the placebo group (P < or = 0.01). The maximum urinary flow rate increased by a mean of 1.4 mL/s (from 11.1 to 12.5 mL/s) in the finasteride group, as compared with an increase of 0.3 mL/s (from 10.9 to 11.2 mL/s) in the placebo group (p < or = 0.01). The mean prostate volume decreased by 21% (from a mean volume of 44.1 cm3 at baseline) in the treatment group; it increased by 8.4% (from a mean volume of 45.8 cm3 at baseline) in the placebo group (p < or = 0.01). In the safety analysis, the proportion of patients who experienced any adverse event was similar in the two groups (81.0% in the treatment group and 81.2% in the placebo group). However, the incidence of adverse events related to sexual dysfunction were significantly higher in the finasteride group than in the placebo group (ejaculation disorder 7.7% v. 1.7% and impotence 15.8% v. 6.3%; p < or = 0.01 for both parameters). CONCLUSION: Finasteride is a well-tolerated and effective alternative to watchful

  9. Predicting adolescent problematic online game use from teacher autonomy support, basic psychological needs satisfaction, and school engagement: a 2-year longitudinal study.

    PubMed

    Yu, Chengfu; Li, Xian; Zhang, Wei

    2015-04-01

    Problematic online game use (POGU) has become a serious global public health concern among adolescents. However, its influencing factors and mediating mechanisms remain largely unknown. This study provides the first longitudinal design to test stage-environment fit theory empirically in POGU. A total of 356 Chinese students reported on teacher autonomy support, basic psychological needs satisfaction, school engagement, and POGU in the autumn of their 7th-9th grade years. Path analyses supported the proposed pathway: 7th grade teacher autonomy support increased 8th grade basic psychological needs satisfaction, which in turn increased 9th grade school engagement, which ultimately decreased 9th grade POGU. Furthermore, 7th grade teacher autonomy support directly increased 9th grade school engagement, which in turn decreased 9th grade POGU. These findings suggest that teacher autonomy support is an important protective predictor of adolescent POGU, and basic psychological needs satisfaction and school engagement are the primary mediators in this association. PMID:25803769

  10. Serum antibody responses to pneumococcal colonization in the first 2 years of life: results from an SE Asian longitudinal cohort study.

    PubMed

    Turner, P; Turner, C; Green, N; Ashton, L; Lwe, E; Jankhot, A; Day, N P; White, N J; Nosten, F; Goldblatt, D

    2013-12-01

    Assessment of antibody responses to pneumococcal colonization in early childhood may aid our understanding of protection and inform vaccine antigen selection. Serum samples were collected from mother-infant pairs during a longitudinal pneumococcal colonization study in Burmese refugees. Maternal and cord sera were collected at birth and infants were bled monthly (1–24 months of age). Nasopharyngeal swabs were taken monthly to detect colonization. Serum IgG titres to 27 pneumococcal protein antigens were measured in 2624 sera and IgG to dominant serotypes (6B, 14, 19F, 19A and 23F) were quantified in 864 infant sera. Antibodies to all protein antigens were detect ablein maternal sera. Titres to four proteins (LytB, PcpA, PhtD and PhtE) were significantly higher in mothers colonized by pneumococci at delivery. Maternally-derived antibodies to PiuA and Spr0096 were associated with delayed pneumococcal acquisition in infants in univariate,but not multivariate models. Controlling for infant age and previous homologous serotype exposure, nasopharyngeal acquisition of serotypes 19A, 23F, 14 or 19F was associated significantly with a ≥2-fold antibody response to the homologous capsule (OR 12.84, 7.52,6.52, 5.33; p <0.05). Acquisition of pneumococcal serotypes in the nasopharynx of infants was not significantly associated with a ≥2-fold rise in antibodies to any of the protein antigens studied. In conclusion, nasopharyngeal colonization in young children resulted in demonstrable serum IgG responses to pneumococcal capsules and surface/virulence proteins. However, the relationship between serum IgG and the prevention of, or response to, pneumococcal nasopharyngeal colonization remains complex. Mechanisms other than serum IgG are likely to have a role but are currently poorly understood. PMID:24255996

  11. The Prospective Intraoperative and Perioperative Ophthalmic ImagiNg with Optical CoherEncE TomogRaphy (PIONEER) Study: 2-year Results

    PubMed Central

    Ehlers, Justis P.; Dupps, William J.; Kaiser, Peter K.; Goshe, Jeff; Singh, Rishi P.; Petkovsek, Dan; Srivastava, Sunil K.

    2014-01-01

    Purpose To evaluate the feasibility, safety, and utility of intraoperative optical coherence tomography (OCT) for use during ophthalmic surgery. Design Prospective, consecutive, case series Methods A prospective, single-center, consecutive, case series was initiated to assess intraoperative OCT in ophthalmic surgery. Intraoperative scanning was performed with a microscope mounted spectral domain OCT system. Disease specific or procedure-specific imaging protocols (e.g., scan type, pattern, size, orientation, density) were utilized for anterior and posterior segment applications. A surgeon feedback form was recorded as part of the study protocol to answer specific questions regarding intraoperative OCT utility immediately after the surgical procedure was completed. Results During the first 24 months of the PIONEER study, 531 eyes were enrolled (275 anterior segment cases and 256 posterior segment surgical cases). Intraoperative OCT imaging was obtained in 518 of 531 eyes (98%). Surgeon feedback indicated that intraoperative OCT informed surgical decision-making and altered surgeon understanding of underlying tissue configurations in 69/144 (48%) lamellar keratoplasty cases and 63/146 (43%) membrane peeling procedures. The most common anterior segment surgical procedure was descemet stripping automated endothelial keratoplasty (DSAEK, n = 135). Vitrectomy with membrane peeling was the most common procedure for posterior segment surgery (n = 154). The median time that surgery was paused to perform intraoperative OCT was 4.9 minutes per scan session. No adverse events were specifically attributed to intraoperative OCT scanning during the procedure. Conclusions Intraoperative OCT is feasible for numerous anterior and posterior segment ophthalmic surgical procedures. A microscope mounted intraoperative OCT system provided efficient imaging during operative procedures. The information gained from intraoperative OCT may impact surgical decision-making in a high frequency

  12. The Role of Human Coronaviruses in Children Hospitalized for Acute Bronchiolitis, Acute Gastroenteritis, and Febrile Seizures: A 2-Year Prospective Study

    PubMed Central

    Jevšnik, Monika; Steyer, Andrej; Pokorn, Marko; Mrvič, Tatjana; Grosek, Štefan; Strle, Franc; Lusa, Lara; Petrovec, Miroslav

    2016-01-01

    Human coronaviruses (HCoVs) are associated with a variety of clinical presentations in children, but their role in disease remains uncertain. The objective of our prospective study was to investigate HCoVs associations with various clinical presentations in hospitalized children up to 6 years of age. Children hospitalized with acute bronchiolitis (AB), acute gastroenteritis (AGE), or febrile seizures (FS), and children admitted for elective surgical procedures (healthy controls) were included in the study. In patients with AB, AGE, and FS, a nasopharyngeal (NP) swab and blood sample were obtained upon admission and the follow-up visit 14 days later, whereas in children with AGE a stool sample was also acquired upon admission; in healthy controls a NP swab and stool sample were taken upon admission. Amplification of polymerase 1b gene was used to detect HCoVs in the specimens. HCoVs-positive specimens were also examined for the presence of several other viruses. HCoVs were most often detected in children with FS (19/192, 9.9%, 95% CI: 6–15%), followed by children with AGE (19/218, 8.7%, 95% CI: 5.3–13.3%) and AB (20/308, 6.5%, 95% CI: 4.0–9.8%). The presence of other viruses was a common finding, most frequent in the group of children with AB (19/20, 95%, 95% CI: 75.1–99.8%), followed by FS (10/19, 52.6%, 95% CI: 28.9–75.6%) and AGE (7/19, 36.8%, 95% CI: 16.3–61.6%). In healthy control children HCoVs were detected in 3/156 (1.9%, 95% CI: 0.4–5.5%) NP swabs and 1/150 (0.7%, 95% CI: 0.02–3.3%) stool samples. It seems that an etiological role of HCoVs is most likely in children with FS, considering that they had a higher proportion of positive HCoVs results than patients with AB and those with AGE, and had the highest viral load; however, the co-detection of other viruses was 52.6%. Trial Registration: ClinicalTrials.gov NCT00987519 PMID:27171141

  13. Decreased use of glucocorticoids in biological-experienced patients with rheumatoid arthritis who initiated intravenous abatacept: results from the 2-year ACTION study

    PubMed Central

    Alten, Rieke; Nüßlein, Hubert; Galeazzi, Mauro; Lorenz, Hanns-Martin; Nurmohamed, Michael T; Bensen, William G; Burmester, Gerd R; Peter, Hans-Hartmut; Pavelka, Karel; Chartier, Mélanie; Poncet, Coralie; Rauch, Christiane; Elbez, Yedid; Le Bars, Manuela

    2016-01-01

    Introduction Prolonged glucocorticoid use may increase the risk of adverse safety outcomes, including cardiovascular events. The European League Against Rheumatism and the Canadian Rheumatology Association advise tapering glucocorticoid dose as rapidly as clinically feasible. There is a paucity of published data on RA that adequately describe concomitant treatment patterns. Methods ACTION (AbataCepT In rOutiNe clinical practice) is a non-interventional cohort study of patients from Europe and Canada that investigated the long-term retention of intravenous abatacept in clinical practice. We assessed concomitant glucocorticoids in patients with established RA who had participated in ACTION and received ≥1 biological agent prior to abatacept initiation. Results The analysis included 1009 patients. Glucocorticoids were prescribed at abatacept initiation in 734 (72.7%) patients at a median 7.5 mg/day dose (n=692). Of the patients who remained on abatacept at 24 months, 40.7% were able to decrease their dose of glucocorticoids, including 26.9% who decreased their dose from >5 mg/day to ≤5 mg/day. Conclusion Reduction and/or cessation of glucocorticoid therapy is possible with intravenous abatacept in clinical practice. PMID:26925253

  14. Personal and demographic factors and change of subjective indoor air quality reported by school children in relation to exposure at Swedish schools: a 2-year longitudinal study.

    PubMed

    Wang, Juan; Smedje, Greta; Nordquist, Tobias; Norbäck, Dan

    2015-03-01

    This paper studies changes in subjective indoor air quality (SIAQ) among school children and relates these data to repeated exposure measurements during a two-year follow-up period. Data on SIAQ and demographic information were gathered by a questionnaire sent to 1476 primary and secondary school pupils in 39 randomly selected schools at baseline and after two years (follow-up). Exposure measurements were applied after questionnaire data were collected at baseline and follow-up in approximately 100 classrooms. The arithmetic mean values for baseline and follow-up were: for indoor air temperature 23.6°C and 21.8°C and for outdoor air flow rate 5.4 L/s and 7.9L/s. Older children, those with atopy at baseline, and those in larger schools reported impaired SIAQ during follow-up. Installation of new ventilation systems, higher personal air flow rate and air exchange rate, and better illumination were associated with improved SIAQ. Higher CO2 levels were associated with impaired SIAQ. In conclusion, sufficient ventilation and illumination in classrooms are essential for the perception of good indoor air quality. PMID:25486639

  15. Icodextrin does not impact infectious and culture-negative peritonitis rates in peritoneal dialysis patients: a 2-year multicentre, comparative, prospective cohort study

    PubMed Central

    Vychytil, Andreas; Remón, César; Michel, Catherine; Williams, Paul; Rodríguez-Carmona, Ana; Marrón, Belén; Vonesh, Ed; van der Heyden, Synke; Filho, Jose C. Divino

    2008-01-01

    Background. Icodextrin is a glucose polymer derived by hydrolysis of cornstarch. The different biocompatibility profile of icodextrin-containing peritoneal dialysis (PD) solutions may have a positive influence on peritoneal host defence. Furthermore, cases of sterile peritonitis potentially associated with icodextrin have been reported. Methods. The primary objective of this multicentre, longitudinal, observational, non-interventional, prospective cohort study, which included 722 PD patients, was to evaluate the incidence of overall peritonitis in patients treated with icodextrin-containing PD solutions (Extraneal™) used during one long-dwell exchange/day compared with those treated with non-icodextrin-containing PD solutions. The secondary objective was to determine if culture-negative peritonitis rates differed between patients treated with icodextrin from two independent manufacturers. All peritonitis episodes were assessed by a Steering Committee in a blind manner. Results. There was no significant difference between icodextrin-treated and control patients in the adjusted overall, culture-positive or culture-negative peritonitis rates. When stratified by the icodextrin supplier, there was no significant difference in the adjusted rate of culture-negative peritonitis episodes between groups. Conclusion. Subjects receiving icodextrin as part of their PD regimen experienced neither a higher rate of culture-negative peritonitis nor a lower rate of infectious peritonitis compared with non-icodextrin users. There was no significant influence of the icodextrin raw material supplier on peritonitis rates. PMID:18556747

  16. The MCT-ketogenic diet as a treatment option in refractory childhood epilepsy: A prospective study with 2-year follow-up.

    PubMed

    Lambrechts, Danielle A J E; de Kinderen, Reina J A; Vles, Hans S H; de Louw, Anton J; Aldenkamp, Albert P; Majoie, Marian J M

    2015-10-01

    The present study assessed the long-term (i.e., 24months) efficacy of the ketogenic diet (KD) as an add-on therapy in children with refractory epilepsy, with focus on seizure frequency, seizure severity, and tolerability. Most patients were treated with the MCT-diet. At one and two years, 33% and 23%, respectively, of the 48 included patients were still on the KD. After three months, one year, and two years of treatment, 16.7% of the patients were responders. The highest responder rate (i.e., 22.9%) was seen at six and nine months of treatment. Of the fifteen patients with seizure clusters during baseline, 60% were responders after three months when looking at cluster reduction and most of them were not responders for the total seizure frequency. From three months of treatment onwards, most of the patients had a relevant decrease in seizure severity which was mainly related to the most severe seizure type. Gastrointestinal dysfunction was often reported, especially in the first six weeks of treatment. Growth deceleration was present in 30% of the patients, and weight reduction in 15%. Improved arousal was mentioned in 30% of patients. No patients developed ECG abnormalities or kidney stones. Increase in lipid profile was rare. The KD is an effective therapy for children with therapy-resistant epilepsy. Effectiveness is reflected in the reduction of seizure frequency as well as in the reduction of seizure severity. After 6months of treatment, it is obvious which patients are responders and tolerate the treatment well. Most of these patients will continue to benefit from the KD for a longer time. Long-term use of the diet was well tolerated. PMID:26301622

  17. In situ measured and simulated seasonal freeze-thaw cycle: A 2-year comparative study between layered and homogeneous field soil profiles

    NASA Astrophysics Data System (ADS)

    Cheng, Q.; Sun, Y.; Jones, S. B.; Vasilyev, V. I.; Popov, V. V.; Wang, G.; Zheng, L.

    2014-11-01

    Annual freeze-thaw cycles of soil significantly impact agricultural and ecosystem services in cold regions. For advancing our understanding of freeze-thaw process, both improved measurements and simulations of coupled-heat-water-transfer (CHWT) phenomenon are needed under different field conditions. This paper focused on a comparative study between a CHWT-model simulation versus in situ measurements of liquid soil water content (LSWC) and soil temperature (ST) at two agricultural field sites. The first site consisted of a layered soil profile with sandy silt loam (0-60 cm) and clay loam (60-130 cm) layers, and the other site was a uniform sand profile (0-110 cm). Measurements were made over two winters between 2011 and 2013, i.e. the first winter is 2011-2012 (year 1) and the second winter is 2012-2013 (year 2), in the northeast of China employing an access-tube dielectric sensor combined with a temperature measurement array. During the freezing period of the year 1 winter, the soil freezing characteristic curves (SFCCs) were determined in situ in relation to the site-specific data of LSWC and ST and subsequently used for the model calibration. For the thawing process of year 1 and the freeze-thaw process of year 2, the resulting ST simulation time series were well-correlated with field measurements. In terms of the resulting LSWC, the numerical simulations also correlated well (R2 > 0.895, RMSE < 0.0381 cm3 cm-3) with the in situ observations of freezing and quasi-steady-state conditions at depths of 50- and 100-cm. The reasons for relatively reduced agreement between simulated and measured LSWC during the thawing stage (i.e., R2 > 0.702, RMSE < 0.0468 cm3 cm-3) are discussed. The resulting time series simulations confirm the model's capability for describing freeze- and thaw-front migration in layered and homogeneous freezing soils.

  18. Change in Care Dependency and Nursing Care Problems in Nursing Home Residents with and without Dementia: A 2-Year Panel Study

    PubMed Central

    2015-01-01

    Over time, chronic conditions like dementia can lead to care dependency and nursing care problems, often necessitating nursing home admission. This panel study (2012–2014) aims to explore changes in care dependency and nursing care problems (incontinence, malnutrition, decubitus, falls and restraints) in residents with and without dementia over time. In total, nine Austrian nursing homes participated, including 258 residents (178 with, 80 without dementia) who completed all five measurements. Data were collected with the International Prevalence Measurement of Care Problems questionnaire, the Care Dependency Scale and the Mini-Mental State Examination-2. Repeated measures ANOVA and crosstabs were used to analyse changes. The results showed that care dependency in dementia residents increased significantly for all 15 items of the Care Dependency Scale, with the highest increase being residents’ day-/night pattern, contact with others, sense of rules/values and communication. In contrast, care dependency in residents without dementia increased for four of the 15 items, with the highest increase being for continence, followed by getting (un)dressed. With respect to the assessed nursing care problems, residents with dementia and those without only differed significantly in terms of an increase in urinary- (12.3% vs. 14.2%), fecal- (17.4% vs. 10%), and double incontinence (16.7% vs. 11.9%). The results indicated that residents with dementia experienced increased care dependency in different areas than residents without dementia. Furthermore, residents with dementia experienced a lower increase in urinary incontinence but a higher increase in fecal- and double incontinence. These results help professionals to identify areas for improvement in dementia care. PMID:26513358

  19. Conducting Phase IV clinical studies: a moral imperative?

    PubMed Central

    Hill, TP

    2012-01-01

    The answer to this question lies in knowing the moral standing of Phase IV studies and whether we ought to conduct them. And to know this, in part, we need to compare them to studies in Phases I, II, and III and then determine where Phase IV studies stand in relation to Phase I–III studies scientifically and commercially.

  20. Vagus nerve stimulation therapy: 2-year prospective open-label study of 40 subjects with refractory epilepsy and low IQ who are living in long-term care facilities.

    PubMed

    Huf, Roger L; Mamelak, Adam; Kneedy-Cayem, Kara

    2005-05-01

    Treating seizures among patients with mental retardation/developmental disabilities (MR/DD) is difficult owing in large part to the presence of additional comorbidities and the resulting need for polytherapy. Therefore, a nonpharmacological treatment option is needed for this population. This prospective, open-label study documented the long-term outcome of 40 low-IQ (<70) patients living in long-term care facilities who received vagus nerve stimulation (VNS) therapy for pharmacoresistant epilepsy. Subjects were seen every 1 to 3 months by their neurologist (R.H.). Seizure frequency, antiepileptic medication, and quality-of-life information were documented preimplantation and quarterly thereafter through 2 years. The surgery and therapy were well tolerated. Seizures were reduced by at least 50% for 11 subjects. Antiepileptic medications were reduced from 3.3 per subject at baseline to an average of 2.3 per subject after 2 years. According to caregiver reports, overall quality of life improved for the majority of subjects; also, using the Client Development Evaluation Report (CDER), statistically significant improvements were reported at both 1 and 2 years in attention span, word usage, clarity of speech, standing balance, washing dishes, and household chores. VNS is a viable treatment option for low-IQ patients with pharmacoresistant epilepsy who are living in long-term care facilities. PMID:15820352

  1. AC Conductivity Studies of Lithium Based Phospho Vanadate Glasses

    NASA Astrophysics Data System (ADS)

    Nagendra, K.; Babu, G. Satish; Reddy, C. Narayana; Gowda, Veeranna

    2011-07-01

    Glasses in the system xLi2SO4-20Li2O-(80-x) [80P2O5-20V2O5] (5⩾x⩾20 mol%) has been prepared by melt quenching method. Dc and ac conductivity has been studied over a wide range of frequency (10 Hz to 10 MHz) and temperature (298 K-523 K). The dc conductivity found to increase with increase of Li2SO4 concentration. The ac conductivities have been fitted to the Almond-West type single power law equation σ(ω) = σ(0)+Aωs where `s' is the power law exponent. The ac conductivity found to increase with increase of Li2SO4 concentration. An attempt is made to elucidate the enhancement of lithium ion conduction in phosphor-vanadate glasses by considering the expansion of network structure.

  2. Study of AC electrical conduction mechanisms in an epoxy polymer

    NASA Astrophysics Data System (ADS)

    Jilani, Wissal; Mzabi, Nissaf; Gallot-Lavallée, Olivier; Fourati, Najla; Zerrouki, Chouki; Zerrouki, Rachida; Guermazi, Hajer

    2015-11-01

    The AC conductivity of an epoxy resin was investigated in the frequency range 10^{-1} - 106 Hz at temperatures ranging from -100 to 120 °C. The frequency dependence of σ_{ac} was described by the law: σ_{ac}=ω \\varepsilon0\\varepsilon^''_{HN}+Aωs. The study of temperature variation of the exponent (s) reveals two conduction models: the AC conduction dependence upon temperature is governed by the small polaron tunneling mechanism (SPTM) at low temperature (-100 -60 °C) and the correlated barrier hopping (CHB) model at high temperature (80-120 °C).

  3. Thermal conductivity of penta-graphene from molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Xu, Wen; Zhang, Gang; Li, Baowen

    2015-10-01

    Using classical equilibrium molecular dynamics simulations and applying the original Tersoff interatomic potential, we study the thermal transport property of the latest two dimensional carbon allotrope, penta-graphene. It is predicted that its room-temperature thermal conductivity is about 167 W/mK, which is much lower than that of graphene. With normal mode decomposition, the accumulated thermal conductivity with respect to phonon frequency and mean free path is analyzed. It is found that the acoustic phonons make a contribution of about 90% to the thermal conductivity, and phonons with mean free paths larger than 100 nm make a contribution over 50%. We demonstrate that the remarkably lower thermal conductivity of penta-graphene compared with graphene results from the lower phonon group velocities and fewer collective phonon excitations. Our study highlights the importance of structure-property relationship and provides better understanding of thermal transport property and valuable insight into thermal management of penta-graphene.

  4. Thermal conductivity of penta-graphene from molecular dynamics study.

    PubMed

    Xu, Wen; Zhang, Gang; Li, Baowen

    2015-10-21

    Using classical equilibrium molecular dynamics simulations and applying the original Tersoff interatomic potential, we study the thermal transport property of the latest two dimensional carbon allotrope, penta-graphene. It is predicted that its room-temperature thermal conductivity is about 167 W/mK, which is much lower than that of graphene. With normal mode decomposition, the accumulated thermal conductivity with respect to phonon frequency and mean free path is analyzed. It is found that the acoustic phonons make a contribution of about 90% to the thermal conductivity, and phonons with mean free paths larger than 100 nm make a contribution over 50%. We demonstrate that the remarkably lower thermal conductivity of penta-graphene compared with graphene results from the lower phonon group velocities and fewer collective phonon excitations. Our study highlights the importance of structure-property relationship and provides better understanding of thermal transport property and valuable insight into thermal management of penta-graphene. PMID:26493918

  5. The electrical conduction of conjugated molecular CAMs studied by a conductive atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Yamamoto, Shin-ichi; Ogawa, Kazufumi

    2006-09-01

    Monomolecular layers containing pyrrolyl groups between two parallel Pt electrodes on a glass substrate by a chemical adsorption technique using N-[11-(trichlorosilyl)undecyl] pyrrole (PNN) were studied. Polymerization with pure water by applying a DC voltage of 10 V between the two Pt electrodes was carried out, and several electric paths were formed between the two Pt electrodes were identified. Conductive probe of an atomic force microscopy (AFM) was used to examine the electrical polymerized paths through the surface of the polypyrrolyl group in a chemically adsorbed monomolecular layer. With a measurement volume of about 0.2 nm (thickness of the monomolecular layer) × 100 μm (the average width of an electric path) × 100 μm (the distance between the Pt electrode and the Au-covered AFM tip), the resistance at room temperature of one electric path was 5 kΩ under ambient conditions. From the results conducted in an atmosphere, the conductivity of a super-long conjugated polypyrrolyl group without any dopant in a lateral direction was ohmically estimated to be at least 5.0 × 10 5 s/m.

  6. Electrical studies on silver based fast ion conducting glassy materials

    NASA Astrophysics Data System (ADS)

    Rao, B. Appa; Kumar, E. Ramesh; Kumari, K. Rajani; Bhikshamaiah, G.

    2014-04-01

    Among all the available fast ion conductors, silver based glasses exhibit high conductivity. Further, glasses containing silver iodide enhances fast ion conducting behavior at room temperature. Glasses of various compositions of silver based fast ion conductors in the AgI-Ag2O-[(1-x)B2O3-xTeO2] (x=0 to1 mol% in steps of 0.2) glassy system have been prepared by melt quenching method. The glassy nature of the compounds has been confirmed by X-ray diffraction. The electrical conductivity (AC) measurements have been carried out in the frequency range of 1 KHz-3MHz by Impedance Analyzer in the temperature range 303-423K. The DC conductivity measurements were also carried out in the temperature range 300-523K. From both AC and DC conductivity studies, it is found that the conductivity increases and activation energy decreases with increasing the concentration of TeO2 as well as with temperature. The conductivity of the present glass system is found to be of the order of 10-2 S/cm at room temperature. The ionic transport number of these glasses is found to be 0.999 indicating that these glasses can be used as electrolyte in batteries.

  7. Electrical studies on silver based fast ion conducting glassy materials

    SciTech Connect

    Rao, B. Appa Kumar, E. Ramesh Kumari, K. Rajani Bhikshamaiah, G.

    2014-04-24

    Among all the available fast ion conductors, silver based glasses exhibit high conductivity. Further, glasses containing silver iodide enhances fast ion conducting behavior at room temperature. Glasses of various compositions of silver based fast ion conductors in the AgI−Ag{sub 2}O−[(1−x)B{sub 2}O{sub 3}−xTeO{sub 2}] (x=0 to1 mol% in steps of 0.2) glassy system have been prepared by melt quenching method. The glassy nature of the compounds has been confirmed by X-ray diffraction. The electrical conductivity (AC) measurements have been carried out in the frequency range of 1 KHz–3MHz by Impedance Analyzer in the temperature range 303–423K. The DC conductivity measurements were also carried out in the temperature range 300–523K. From both AC and DC conductivity studies, it is found that the conductivity increases and activation energy decreases with increasing the concentration of TeO{sub 2} as well as with temperature. The conductivity of the present glass system is found to be of the order of 10{sup −2} S/cm at room temperature. The ionic transport number of these glasses is found to be 0.999 indicating that these glasses can be used as electrolyte in batteries.

  8. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the... be met. (a) All samples having PCB concentrations greater than or equal to the level of concern, as... found to have a PCB concentration greater than the level of concern as measured by the...

  9. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the... be met. (a) All samples having PCB concentrations greater than or equal to the level of concern, as... found to have a PCB concentration greater than the level of concern as measured by the...

  10. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the... be met. (a) All samples having PCB concentrations greater than or equal to the level of concern, as... found to have a PCB concentration greater than the level of concern as measured by the...

  11. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the... be met. (a) All samples having PCB concentrations greater than or equal to the level of concern, as... found to have a PCB concentration greater than the level of concern as measured by the...

  12. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze the... be met. (a) All samples having PCB concentrations greater than or equal to the level of concern, as... found to have a PCB concentration greater than the level of concern as measured by the...

  13. A Framework for Conducting ESL/EFL Construct Validation Studies.

    ERIC Educational Resources Information Center

    Mouw, John T.; Perkins, Kyle

    The purpose for which a test is used and the examinees' stage of learning are two anchor points that are incorporated into a suggested framework for conducting construct validation studies for tests of students with English as a second language (ESL) or English as a foreign language (EFL). The framework includes the use of generalizability theory,…

  14. Recent Studies of RF Breakdown Physics in Normal Conducting Cavities

    SciTech Connect

    Dolgashev, Valery; /SLAC

    2012-06-11

    The operating accelerating gradient in normal conducting accelerating structures is often limited by rf breakdown. The behavior of the rf breakdown depends on multiple parameters, including the input rf power, rf circuit, cavity shape and material. Here we discuss recent experimental data and theoretical studies of rf breakdown physics.

  15. Treatment of Conduct Disorders in Childhood: A Comparative Study.

    ERIC Educational Resources Information Center

    Robinson, Elizabeth A.

    Children evidencing conduct disorders comprise the bulk of clinical referrals. Longitudinal studies have found that the prognosis for these children is poor in that the majority exhibit antisocial behavior in adulthood. In order to compare two methods of treatment, relationship-based and contingency management, 53 children (33 boys, 20 girls),…

  16. Paraphasias in Multilingual Conduction Aphasia: A Single Case Study

    ERIC Educational Resources Information Center

    Hegde, Medha; Bhat, Sapna

    2007-01-01

    Conduction aphasia is a type of fluent aphasia, which is caused due to the damage to the supramarginal gyrus and arcuate fasciculus resulting in repetition disturbance. It has been speculated that linguistic system in bilingual aphasics can breakdown in different ways across languages. There is a lack of detailed linguistic studies in specific…

  17. Preparation, characterization and conductivity studies of chlorinated natural rubber

    NASA Astrophysics Data System (ADS)

    M, Subburaj; Ramesan, M. T.; Pradyumnan, P. P.

    2014-10-01

    Chlorinated natural rubber (CNR) was prepared by alkaline hydrolysis of chloroform using phase transfer catalyst. The chlorination in CNR was monitored by FTIR and UV spectroscopy and these studies indicated the formation of dichloro cyclopropyl ring to the double bond of natural rubber (NR). XRD and SEM analysis revealed the extent of chlorination in natural rubber. Electrical properties such as AC conductivity, dielectric constant and dielectric loss of CNR was higher than that of NR. Conductivity of NR increased with the increase in the concentration of chlorine percentage. LOI values indicated that the chemical modification imparts better flame resistant to NR.

  18. Heat conduction in multifunctional nanotrusses studied using Boltzmann transport equation

    NASA Astrophysics Data System (ADS)

    Dou, Nicholas G.; Minnich, Austin J.

    2016-01-01

    Materials that possess low density, low thermal conductivity, and high stiffness are desirable for engineering applications, but most materials cannot realize these properties simultaneously due to the coupling between them. Nanotrusses, which consist of hollow nanoscale beams architected into a periodic truss structure, can potentially break these couplings due to their lattice architecture and nanoscale features. In this work, we study heat conduction in the exact nanotruss geometry by solving the frequency-dependent Boltzmann transport equation using a variance-reduced Monte Carlo algorithm. We show that their thermal conductivity can be described with only two parameters, solid fraction and wall thickness. Our simulations predict that nanotrusses can realize unique combinations of mechanical and thermal properties that are challenging to achieve in typical materials.

  19. AC Conductivity Studies of Lithium Based Phospho Vanadate Glasses

    SciTech Connect

    Nagendra, K.; Babu, G. Satish; Gowda, Veeranna; Reddy, C. Narayana

    2011-07-15

    Glasses in the system xLi{sub 2}SO{sub 4}-20Li{sub 2}O-(80-x) [80P{sub 2}O{sub 5}-20V{sub 2}O{sub 5}](5{>=}x{>=}20 mol%) has been prepared by melt quenching method. Dc and ac conductivity has been studied over a wide range of frequency (10 Hz to 10 MHz) and temperature (298 K-523 K). The dc conductivity found to increase with increase of Li{sub 2}SO{sub 4} concentration. The ac conductivities have been fitted to the Almond-West type single power law equation {sigma}({omega}) = {sigma}(0)+A{omega}{sup s} where 's' is the power law exponent. The ac conductivity found to increase with increase of Li{sub 2}SO{sub 4} concentration. An attempt is made to elucidate the enhancement of lithium ion conduction in phosphor-vanadate glasses by considering the expansion of network structure.

  20. Metal-containing polyacrylonitriles: ESR studies and conductivity

    SciTech Connect

    Bronstein, L.M.; ERemin, V.S.; Solodovnikov, S.P.

    1995-12-01

    Metal-containing polyacrylonitriles (PAN) synthesized by the complexation of VI B group metal hexacarbonyls with PAN nitrile groups were studied during thermolysis in air at 220{degrees}C to find conditions for preparation of conductive polymeric films. It was shown that increase of W content in polymer leads to significant decrease of {gamma}{sub v} to magnitude about 10{sup -16} {Omega}/cm as compared with conductivity of thermolized initial PAN ({gamma}{sub v} = 10{sup -11} {Omega}/cm). In contrast, PAN-Cr samples heated under the same temperature-time conditions in an external field 40-50 kV/cm show the increase of conductivity: at a chromium content of 3.1 wt.% {gamma}{sub v} reaches a value of 10{sup -5} {Omega}/cm. According to ESR study, the thermolized PAN-Cr contains Cr{sub 2}O{sub 3} particles (a broad ESR signal at H=65 Oe); in so doing rough estimate of Cr{sub 2}O{sub 3} dispersity gives a value about 3 nm. Upon thermolysis of PAN-Mo in external field the enhancement of conductivity also occurs. The values of the temperature resistance factors for PAN-Cr and PAN-Mo in the temperature range 20-200{degrees}C reaches a value 1-9 x 10{sup -4} K{sup -1}.

  1. A Randomized Controlled Trial to Examine the Effect of 2-Year Vitamin B12 and Folic Acid Supplementation on Physical Performance, Strength, and Falling: Additional Findings from the B-PROOF Study.

    PubMed

    Swart, Karin M A; Ham, Annelies C; van Wijngaarden, Janneke P; Enneman, Anke W; van Dijk, Suzanne C; Sohl, Evelien; Brouwer-Brolsma, Elske M; van der Zwaluw, Nikita L; Zillikens, M Carola; Dhonukshe-Rutten, Rosalie A M; van der Velde, Nathalie; Brug, Johannes; Uitterlinden, André G; de Groot, Lisette C P G M; Lips, Paul; van Schoor, Natasja M

    2016-01-01

    Elevated homocysteine concentrations are associated with a decline in physical function in elderly persons. Homocysteine-lowering therapy may slow down this decline. This study aimed to examine the effect of a 2-year intervention of vitamin B12 and folic acid supplementation on physical performance, handgrip strength, and risk of falling in elderly subjects in a double-blind, randomized placebo-controlled trial. Participants aged ≥65 years with elevated plasma homocysteine concentrations [12-50 µmol/L (n = 2919)] were randomly assigned to daily supplementation of 500 µg vitamin B12, 400 µg folic acid, and 600 IU vitamin D3, or to placebo with 600 IU vitamin D3. Physical performance (range 0-12) and handgrip strength (kg) were measured at baseline and after 2 years. Falls were reported prospectively on a research calendar. Intention-to-treat (primary) and per-protocol (secondary) analyses were performed. Physical performance level and handgrip strength significantly decreased during the follow-up period, but this decline did not differ between groups. Moreover, time to first fall was not significantly different (HR: 1.0, 95% CI 0.9-1.2). Secondary analyses on a per-protocol base identified an interaction effect with age on physical performance. In addition, the treatment was associated with higher follow-up scores on the walking test (cumulative OR: 1.3, 95% CI 1.1-1.5). Two-year supplementation of vitamin B12 and folic acid was neither effective in reducing the age-related decline in physical performance and handgrip strength, nor in the prevention of falling in elderly persons. Despite the overall null-effect, the results provide indications for a positive effect of the intervention on gait, as well as on physical performance among compliant persons >80 years. These effects should be further tested in future studies. PMID:26412463

  2. Paper use in research ethics applications and study conduct.

    PubMed

    Chakladar, Abhijoy; Eckstein, Sue; White, Stuart M

    2011-02-01

    Application for Research Ethics Committee (REC) approval and the conduct of medical research is paper intensive. This retrospective study examined all applications to a single REC in the south of England over one year. It estimated the mass of paper used, comparing the proportional paper consumption of different trial types and during different stages of the research process, quantifying the consumption in terms of carbon dioxide emissions. In 2009, 68 trials were submitted to the REC. Total paper consumption for the REC process and study conduct was 176,150 sheets of A4 paper (879 kg), equivalent to an estimated 11.5 million sheets (88 tonnes, 2100 trees) a year for the U.K.; the REC process accounted for 26.4%. REC applications and the conduct of approved trials generate considerable environmental impact through paper consumption contributing to the NHS's carbon footprint. Paper use might be reduced through the implementation of digital technologies and revised research methods, namely changing attitudes in both researchers and ethics committees. PMID:21404784

  3. Electronic conductivity studies on oxyhalide glasses containing TMO

    NASA Astrophysics Data System (ADS)

    Vijayatha, D.; Viswanatha, R.; Sujatha, B.; Narayana Reddy, C.

    2016-05-01

    Microwave-assisted synthesis is cleaner, more economical and much faster than conventional methods. The development of new routes for the synthesis of solid materials is an integral part of material science and technology. The electronic conductivity studies on xPbCl2 - 60 PbO - (40-x) V2O5 (1 ≥ x ≤ 10) glass system has been carried out over a wide range of composition and temperature (300 K to 423 K). X-ray diffraction study confirms the amorphous nature of the samples. The Scanning electron microscopic studies reveal the formation of cluster like morphology in PbCl2 containing glasses. The d.c conductivity exhibits Arrhenius behaviour and increases with V2O5 concentration. Analysis of the results is interpreted in view Austin-Mott's small polaron model of electron transport. Activation energies calculated using regression analysis exhibit composition dependent trend and the variation is explained in view of the structure of lead-vanadate glass.

  4. Computer-Guided Implant Surgery in Fresh Extraction Sockets and Immediate Loading of a Full Arch Restoration: A 2-Year Follow-Up Study of 14 Consecutively Treated Patients.

    PubMed

    Daas, M; Assaf, A; Dada, K; Makzoumé, J

    2015-01-01

    Statement of Problem. Low scientific evidence is identified in the literature for combining implant placement in fresh extraction sockets with immediate function. Moreover, the few studies available on immediate implants in postextraction sites supporting immediate full-arch rehabilitation clearly lack comprehensive protocols. Purpose. The purpose of this study is to report outcomes of a comprehensive protocol using CAD-CAM technology for surgical planning and fabrication of a surgical template and to demonstrate that immediate function can be easily performed with immediate implants in postextraction sites supporting full-arch rehabilitation. Material and Methods. 14 subjects were consecutively rehabilitated (13 maxillae and 1 mandible) with 99 implants supporting full-arch fixed prostheses followed between 6 and 24 months (mean of 16 months). Outcome measures were prosthesis and implant success, biologic and prosthetic complications, pain, oedema evaluation, and radiographic marginal bone levels at surgery and then at 6, 12, 18, and 24 months. Data were analyzed with descriptive statistics. Results. The overall cumulative implant survival rate at mean follow-up time of 16 months was 97.97%. The average marginal bone loss was 0,9 mm. Conclusions. Within the limitations of this study, the results validate this treatment modality for full-arch rehabilitations with predictable outcomes and high survival rate after 2 years. PMID:26064119

  5. Computer-Guided Implant Surgery in Fresh Extraction Sockets and Immediate Loading of a Full Arch Restoration: A 2-Year Follow-Up Study of 14 Consecutively Treated Patients

    PubMed Central

    Daas, M.; Assaf, A.; Dada, K.; Makzoumé, J.

    2015-01-01

    Statement of Problem. Low scientific evidence is identified in the literature for combining implant placement in fresh extraction sockets with immediate function. Moreover, the few studies available on immediate implants in postextraction sites supporting immediate full-arch rehabilitation clearly lack comprehensive protocols. Purpose. The purpose of this study is to report outcomes of a comprehensive protocol using CAD-CAM technology for surgical planning and fabrication of a surgical template and to demonstrate that immediate function can be easily performed with immediate implants in postextraction sites supporting full-arch rehabilitation. Material and Methods. 14 subjects were consecutively rehabilitated (13 maxillae and 1 mandible) with 99 implants supporting full-arch fixed prostheses followed between 6 and 24 months (mean of 16 months). Outcome measures were prosthesis and implant success, biologic and prosthetic complications, pain, oedema evaluation, and radiographic marginal bone levels at surgery and then at 6, 12, 18, and 24 months. Data were analyzed with descriptive statistics. Results. The overall cumulative implant survival rate at mean follow-up time of 16 months was 97.97%. The average marginal bone loss was 0,9 mm. Conclusions. Within the limitations of this study, the results validate this treatment modality for full-arch rehabilitations with predictable outcomes and high survival rate after 2 years. PMID:26064119

  6. Conductive Education: Feasibility Study on Developing a National Curriculum Plan for Those Working in Conductive Education in New Zealand.

    ERIC Educational Resources Information Center

    Wagner, Graham A.

    This study sought to determine whether there are national training needs among staff of conductive education programs in New Zealand. Conductive education is a unified system of education for children and adults with a motor disorder whose disability has been caused by damage to the central nervous system. The study, which focuses primarily on…

  7. Summary of remote vehicle emissions sensing studies conducted in Wisconsin

    SciTech Connect

    Rendahl, C.S.

    1996-10-01

    The State of Wisconsin received Congestion Mitigation & Air Quality Improvement (CMAQ) grants to conduct studies during the summers of 1993 and 1994 to determine the effectiveness of using a remote sensing device (RSD) to fulfill the {open_quotes}On-Road{close_quotes} emissions testing requirements of the Clean Air Act Amendments (CAAA) of 1990. The RSD used in the Wisconsin studies was designed and patented by Dr. Donald H. Stedman of the University of Denver, and was produced by Remote Sensing Technologies, Inc. (RSTi) of Tucson, AZ. This paper will summarize sampling activities, intercomparison results with the existing Basic vehicle inspection/maintenance (IM) centralized test facilities, and look at the results of data collected on close to 200,000 vehicles tested in the two year period.

  8. Thermal conductivity at the nanoscale: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Lyver, John W., IV

    With the growing use of nanotechnology and nanodevices in many fields of engineering and science, a need for understanding the thermal properties of such devices has increased. The ability for nanomaterials to conduct heat is highly dependent on the purity of the material, internal boundaries due to material changes and the structure of the material itself. Experimentally measuring the heat transport at the nanoscale is extremely difficult and can only be done as a macro output from the device. Computational methods such as various Monte Carlo (MC) and molecular dynamics (MD) techniques for studying the contribution of atomic vibrations associated with heat transport properties are very useful. The Green--Kubo method in conjunction with Fourier's law for calculating the thermal conductivity, kappa, has been used in this study and has shown promise as one approach well adapted for understanding nanosystems. Investigations were made of the thermal conductivity using noble gases, modeled with Lennard-Jones (LJ) interactions, in solid face-centered cubic (FCC) structures. MC and MD simulations were done to study homogeneous monatomic and binary materials as well as slabs of these materials possessing internal boundaries. Additionally, MD simulations were done on silicon carbide nanowires, nanotubes, and nanofilaments using a potential containing two-body and three-body terms. The results of the MC and MD simulations were matched against available experimental and other simulations and showed that both methods can accurately simulate real materials in a fraction of the time and effort. The results of the study show that in compositionally disordered materials the selection of atomic components by their mass, hard-core atomic diameter, well depth, and relative concentration can change the kappa by as much as an order of magnitude. It was found that a 60% increase in mass produces a 25% decrease in kappa. A 50% increase in interatomic strength produces a 25% increase in

  9. Thermal conductivity and rectification study of restructured Graphene

    NASA Astrophysics Data System (ADS)

    Arora, Anuj

    Electronics' miniaturization, has led to search for better thermal management techniques and discovery of important transport phenomenon. Thermal rectification, directionally preferential heat transport analogous to electrical diode, is one such technique, garnering tremendous interest. Its possibility has been explored through structural asymmetry, introducing a differential phonon density of states in hot and cold regions. As of now, mass and shape asymmetries have been studied, both experimentally and theoretically. However, strict requirements of material length being shorter than phonon mean free path and phonon coherence preservation at surface, makes connecting two materials with different temperature-dependent thermal conductivities, a more natural approach. To avoid resultant thermal boundary resistance and integration complexities, we achieve the affect in single material, by restructuring a region of Graphene by introducing defects. The asymmetry impedes ballistic phonon transport, modulating temperature dependence of thermal conductivity in the two regions. We perform deviational Monte Carlo simulations based on Energy-based formulation to microscopically investigate phonon transport, possibility and optimal conditions for thermal rectification. The proposed method uses phonon properties obtained from first principle, treat phonon-boundary scattering explicitly with properties drawn from Bose-Einstein Distribution.

  10. Triadic Interaction among Newly Acquainted 2-Year-Olds

    ERIC Educational Resources Information Center

    Ishikawa, Fumiko; Hay, Dale F.

    2006-01-01

    Are children as young as 2 years old able to interact in groups of three? The study applied the family triad model first introduced by Parke, Power, and Gottman (1979) to the case of peer interaction. In Experiment 1, the model was refined for use in studies of peer interaction and applied to an existing dataset of 16 triads of newly acquainted…

  11. Proton Conduction and Defect Studies in Acceptor - Potassium Tantalate Crystals.

    NASA Astrophysics Data System (ADS)

    Lee, Wing Kit

    The protonic transport properties of the cubic perovskite structured crystal KTaO(,3) doped with transition metal ions (Fe('3+), Cu('2+), etc.) are studied. These dopants substitute for the Ta('5+) ions and require oxygen vacancies for charge compensation. Protons are introduced by annealing the doped crystals in water vapor. A sharp IR peak at 3472 cm('-1) is observed at room temperature. This OH('-) band can be removed by vacuum annealing. Undoped crystals are not susceptible to H('+) incorporation. A reaction is proposed for the incorporation of H('+): H(,2)O + V(,o) (--->) O(,o)('x) + 2H(.). A saturation content of H('+) is always attained which is independent of both pH(,2)O and annealing temperature. Impendence analysis is employed to obtain the bulk electrical conductivity, (sigma). The (sigma) of H('+) charged samples is an order of magnitude higher than that without H('+). The activation energy for conduction, E(,H), for H('+) charged samples is close to 1.05 eV, irrespective of nature of dopants. A rough monotonic relation between (sigma) and (alpha)(,OH), the IR absorption coefficient, is observed. Conductivity calculated from diffusion data is in rough agreement with the measured (sigma). In addi- tion, the protonic transport number is found to be almost unity in an electrochemical cell experiment. The position of the IR peak is the same for different dopants, suggesting no association between dopant and H('+). The presence of an EPR axial spectrum in H('+) free Fe-doped samples and its conversion to a cubic spectrum after charging with H('+) favors the suggestion that H('+) dissociates from dopants. No dielectric relaxa- tion peak related to H('+) is ever observed. E(,H) thus corresponds to migrational energy only. The migration of the proton is probably just the jump of H('+) between neighboring O('2-) ions in the direction of O-H vibration. The isotope effect on (sigma) is also studied when H('+) is replaced entirely by D('+). The result is non

  12. Reviewing existing knowledge prior to conducting animal studies.

    PubMed

    Knight, Andrew

    2008-12-01

    Highly polarised viewpoints about animal experimentation have often prevented agreement. However, important common ground between advocates and opponents was demonstrated within a discussion forum hosted at www.research-methodology.org.uk in July-August 2008, by the independent charity, SABRE Research UK. Agreement existed that many animal studies have methodological flaws - such as inappropriate sample sizes, lack of randomised treatments, and unblinded outcome assessments - that may introduce bias and limit statistical validity. There was also agreement that systematic reviews of the human utility of animal models yield the highest quality of evidence, as their reliance on methodical and impartial methods to select significant numbers of animal studies for review, serves to minimise bias. Unfortunately, disagreement remained that animal experimental licence applications should reference systematic reviews of existing studies, before approval. The UK Medical Research Council requires that researchers planning human clinical trials must reference such reviews of related previous work. Existing knowledge is thereby fully and appropriately utilised, and redundant experimentation is avoided. However, objections were raised that a similar requirement would interfere with animal experimental licensing, because, to date, there have been very few systematic reviews of animal studies. In fact, the relative dearth of such reviews is a matter of considerable concern, and may partially explain the very poor human success rates of drugs that appear safe and/or efficacious in animal trials. Nevertheless, the disturbing number of human trials which have proceeded concurrently with, or prior to, animal studies, or have continued despite equivocal evidence of efficacy in animals, clearly demonstrate that many researchers fail to conduct adequate prior reviews of existing evidence. Where neither sufficient primary studies, nor systematic reviews of such studies, exist, for citation

  13. Phase behaviour and conductivity study of electrolytes in supercritical hydrofluorocarbons.

    PubMed

    Bartlett, Philip N; Cook, David C; George, Michael W; Ke, Jie; Levason, William; Reid, Gillian; Su, Wenta; Zhang, Wenjian

    2011-01-01

    The purpose of this work was to characterise supercritical hydrofluorocarbons (HFC) that can be used as solvents for electrodeposition. The phase behaviour of CHF(3), CH(2)F(2), and CH(2)FCF(3) containing [NBu(n)(4)][BF(4)], [NBu(n)(4)][B{3,5-C(6)H(3)(CF(3))(2)}(4)] and Na[B{3,5-C(6)H(3)(CF(3))(2)}(4)] was studied and the conditions for forming a single supercritical phase established. Although all three HFCs are good solvents for [NBu(n)(4)][BF(4)] the results show that the CH(2)F(2) system has the lowest p(r) for dissolving a given amount of [NBu(n)(4)][BF(4)]. The solubility of Na[B{3,5-C(6)H(3)(CF(3))(2)}(4)] in CH(2)F(2) was found to be unexpectedly high. Studies of the phase behaviour of CH(2)F(2) containing [NBu(n)(4)][BF(4)] and [Cu(CH(3)CN)(4)][BF(4)] showed that the copper complex was unstable in the absence of CH(3)CN. For CHF(3), [Cu(hfac)(2)] was more soluble and more stable than [Cu(CH(3)CN)(4)][BF(4)] and only increased the phase-separation pressure by a moderate amount. Studies of the conductivity of [NBu(n)(4)][B(C(6)F(5))(4)], [NBu(n)(4)][B{3,5-C(6)H(3)(CF(3))(2)}(4)], [NR(f)Bu(n)(3)][B{3,5-C(6)H(3)(CF(3))(2)}(4)] (R(f) = (CH(2))(3)C(7)F(15)), and Na[B{3,5-C(6)H(3)(CF(3))(2)}(4)] were carried out in scCH(2)F(2). The results show that these salts are more conducting than [NBu(n)(4)][BF(4)] under the same conditions although the increase is much less significant than that reported in previous work in supercritical CO(2) + CH(3)CN. Consequently, either [NBu(n)(4)][BF(4)] or the corresponding BARF salts would be suitable background electrolytes for electrodeposition from scCH(2)F(2). PMID:21072413

  14. A Protocol for Conducting Rainfall Simulation to Study Soil Runoff

    PubMed Central

    Kibet, Leonard C.; Saporito, Louis S.; Allen, Arthur L.; May, Eric B.; Kleinman, Peter J. A.; Hashem, Fawzy M.; Bryant, Ray B.

    2014-01-01

    Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial urea, a common form of nitrogen (N) fertilizer, following a rainfall event that occurs within 24 hr after fertilizer application. Although urea is assumed to be readily hydrolyzed to ammonium and therefore not often available for transport, recent studies suggest that urea can be transported from agricultural soils to coastal waters where it is implicated in harmful algal blooms. A rainfall simulator was used to apply a consistent rate of uniform rainfall across packed soil boxes that had been prewetted to different soil moisture contents. By controlling rainfall and soil physical characteristics, the effects of antecedent soil moisture on urea loss were isolated. Wetter soils exhibited shorter time from rainfall initiation to runoff initiation, greater total volume of runoff, higher urea concentrations in runoff, and greater mass loadings of urea in runoff. These results also demonstrate the importance of controlling for antecedent soil moisture content in studies designed to isolate other variables, such as soil physical or chemical characteristics, slope, soil cover, management, or rainfall characteristics. Because rainfall simulators are designed to deliver raindrops of similar size and velocity as natural rainfall, studies conducted under a standardized protocol can yield valuable data that, in turn, can be used to develop models for predicting the fate and transport of pollutants in runoff. PMID:24748061

  15. A protocol for conducting rainfall simulation to study soil runoff.

    PubMed

    Kibet, Leonard C; Saporito, Louis S; Allen, Arthur L; May, Eric B; Kleinman, Peter J A; Hashem, Fawzy M; Bryant, Ray B

    2014-01-01

    Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial urea, a common form of nitrogen (N) fertilizer, following a rainfall event that occurs within 24 hr after fertilizer application. Although urea is assumed to be readily hydrolyzed to ammonium and therefore not often available for transport, recent studies suggest that urea can be transported from agricultural soils to coastal waters where it is implicated in harmful algal blooms. A rainfall simulator was used to apply a consistent rate of uniform rainfall across packed soil boxes that had been prewetted to different soil moisture contents. By controlling rainfall and soil physical characteristics, the effects of antecedent soil moisture on urea loss were isolated. Wetter soils exhibited shorter time from rainfall initiation to runoff initiation, greater total volume of runoff, higher urea concentrations in runoff, and greater mass loadings of urea in runoff. These results also demonstrate the importance of controlling for antecedent soil moisture content in studies designed to isolate other variables, such as soil physical or chemical characteristics, slope, soil cover, management, or rainfall characteristics. Because rainfall simulators are designed to deliver raindrops of similar size and velocity as natural rainfall, studies conducted under a standardized protocol can yield valuable data that, in turn, can be used to develop models for predicting the fate and transport of pollutants in runoff. PMID:24748061

  16. Association between inflammatory cytokines and the risk of post-stroke depression, and the effect of depression on outcomes of patients with ischemic stroke in a 2-year prospective study

    PubMed Central

    Jiao, Jian-Tong; Cheng, Chao; Ma, Ying-Jun; Huang, Jin; Dai, Min-Chao; Jiang, Chen; Wang, Cheng; Shao, Jun-Fei

    2016-01-01

    The association between inflammatory cytokines and the risk of post-stroke depression (PSD) remains unclear. The aim of the present study was to investigate this association and the effect of PSD on the outcomes of ischemic stroke patients. A total of 355 patients who had experienced ischemic stroke participated in inflammatory cytokine detection by ELISA, in addition to depression, quality of life (QOL) and body performance testing. Cox regression was used to evaluate the associations between PSD risk, inflammatory cytokines and the outcomes of patients. Measurement data was evaluated using Student's t test, and counted data was measured by χ2 test. The incidence of PSD during the 2-year follow-up was 23.1%. The risk of PSD elevated with increased interleukin (IL)-6 expression levels [hazard ratio (HR)=3.18; 95% confidence interval (CI), 1.37–7.36] following the adjustment of confounders. However, no significant associations were identified between PSD and other inflammatory cytokines. QOL and body performance in the depressed group were significantly worse compared with those in the non-depressed group. The risk of stroke recurrence in patients with depression increased two-fold compared with patients without depression (HR=2.020; 95% CI, 1.123–3.635; Ptrend=0.019). No significant associations between PSD and the risk of mortality (HR=1.497; 95% CI, 0.547–4.098) were observed. In conclusion, depression is prevalent in patients following ischemic stroke. IL-6 is positively associated with the risk of PSD, and may predict its development in patients following ischemic stroke. PSD correlates with outcomes of patients, and the effective management of PSD may improve the prognosis of patients. PMID:27588080

  17. Practical aspects of designing and conducting pharmacoeconomic studies in Japan.

    PubMed

    Doherty, Jim; Sato, Keiko

    2003-01-01

    The advent of simultaneous global clinical trials and drug registration strategies has increased the demand for global pharmacoeconomic strategies. Outcomes researchers in pharmaceutical companies are faced with the challenge of assessing at a strategic level what pharmacoeconomic data are most useful in Japan and when, and then deciding at a tactical level what type of study designs are feasible. This paper is written mainly for the benefit of researchers working outside of Japan in the pharmaceutical/medical device industry or academia who are interested in conducting research in Japan. We reviewed the existing pharmacoeconomic literature in Japan, and found that the number of studies per year has been steadily increasing. The majority of studies have been cost-effectiveness and cost-consequence analyses. Typical data sources available in Japan are somewhat limited compared with other Western countries. However, charge data can be easily accessed through the national uniform reimbursement fee system and these data are particularly relevant for pharmaceutical pricing negotiations with the Ministry of Health, Labor and Welfare (MHLW). The present use of pharmacoeconomic data by pharmaceutical companies is mainly for pricing negotiations but recent reforms make certain types of data useful for marketing strategies too. The demand for pharmacoeconomic data may increase because of upcoming MHLW pharmaceutical pricing and/or recent health insurance system reforms. Economic evaluation of medical technologies in Japan, though lagging behind North America, Australia and Europe, has the potential to rapidly gather momentum as increasing cost-escalation worries contribute to a growing interest in pharmacoeconomic data. PMID:12959624

  18. Study for Electric Device Assembly Process Using Conductive Adhesive

    NASA Astrophysics Data System (ADS)

    Fujino, Junji

    Electric devices with semiconductors are applied to all apparatus including substation equipment, transport machines, home electronics, and cellular phones. Power modules deal large current, and high frequency/optical modules control GHz band signals. As a result, these semiconductors have more than 100 times heat density of memory or MPU chips. Pb-rich high temperature solder and expensive Au-rich solder are applied to these modules, however, thermal stress might be a problem not only for long-term reliability but also for the initial characteristics. The authors studied the assembly of these electric devices using conductive adhesive as a substitute bonding material. We proved that atmospheric aluminum oxides caused electric resistance and that power chips with long rectangle sides over 10 mm have a much larger thermal resistance than theoretical values. We found that it is effective to scratch and remove these oxides through transferred adhesive on aluminum electrodes and to diebond them onto the solder projection previously formed on the die pads.

  19. A minimum 2-year comparative study of autologous cancellous bone grafting versus beta-tricalcium phosphate in anterior cervical discectomy and fusion using a rectangular titanium stand-alone cage.

    PubMed

    Yamagata, Toru; Naito, Kentaro; Arima, Hironori; Yoshimura, Masaki; Ohata, Kenji; Takami, Toshihiro

    2016-07-01

    Although titanium stand-alone cages are commonly used in anterior cervical discectomy and fusion (ACDF), there are several concerns such as cage subsidence after surgery. The efficacy of β-tricalcium phosphate (β-TCP) granules as a packing material in 1- or 2-level ACDF using a rectangular titanium stand-alone cage is not fully understood. The purpose of this study is to investigate the validity of rectangular titanium stand-alone cages in 1- and 2-level ACDF with β-TCP. This retrospective study included 55 consecutive patients who underwent ACDF with autologous iliac cancellous bone grafting and 45 consecutive patients with β-TCP grafting. All patients completed at least 2-year postoperative follow-up. Univariate and multivariate analyses were performed to examine the associations between study variables and nonunion after surgery. Significant neurological recovery after surgery was obtained in both groups. Cage subsidence was noted in 14 of 72 cages (19.4 %) in the autograft group and 12 of 64 cages (18.8 %) in the β-TCP group. A total of 66 cages (91.7 %) in the autograft group showed osseous or partial union, and 58 cages (90.6 %) in the β-TCP group showed osseous or partial union by 2 years after surgery. There were no significant differences in cage subsidence and the bony fusion rate between the two groups. Multivariate analysis using a logistic regression model showed that fusion level at C6/7, 2-level fusion, and cage subsidence of grades 2-3 were significantly associated with nonunion at 2 years after surgery. Although an acceptable surgical outcome with negligible complication appears to justify the use of rectangular titanium stand-alone cages in 1- and 2-level ACDF with β-TCP, cage subsidence after surgery needs to be avoided to achieve acceptable bony fusion at the fused segments. Fusion level at C6/7 or 2-level fusion may be another risk factor of nonunion. PMID:27098659

  20. Highly anisotropic thermal conductivity of arsenene: An ab initio study

    NASA Astrophysics Data System (ADS)

    Zeraati, Majid; Vaez Allaei, S. Mehdi; Abdolhosseini Sarsari, I.; Pourfath, Mahdi; Donadio, Davide

    2016-02-01

    Elemental two-dimensional (2D) materials exhibit intriguing heat transport and phononic properties. Here we have investigated the lattice thermal conductivity of newly proposed arsenene, the 2D honeycomb structure of arsenic, using ab initio calculations. Solving the Boltzmann transport equation for phonons, we predict a highly anisotropic thermal conductivity of 30.4 and 7.8 W/mK along the zigzag and armchair directions, respectively, at room temperature. Our calculations reveal that phonons with mean free paths between 20 nm and 1 μ m provide the main contribution to the large thermal conductivity in the zigzag direction; mean free paths of phonons contributing to heat transport in the armchair directions range between 20 and 100 nm. The obtained anisotropic thermal conductivity and feasibility of synthesis, in addition to high electron mobility reported elsewhere, make arsenene a promising material for nanoelectronic applications and thermal management.

  1. Comparative Study of the Thermal Conductivity of Solid Biomass Fuels

    PubMed Central

    2016-01-01

    The thermal conductivity of solid biomass fuels is useful information in the investigation of biomass combustion behavior and the development of modeling especially in the context of large scale power generation. There are little published data on the thermal conductivity of certain types of biomass such as wheat straw, miscanthus, and torrefied woods. Much published data on wood is in the context of bulk materials. A method for determining the thermal conductivities of small particles of biomass fuels has been developed using a custom built test apparatus. Fourteen different samples of various solid biomass fuel were processed to form a homogenized pellet for analysis. The thermal conductivities of the pelletized materials were determined and compared against each other and to existing data. PMID:27041819

  2. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: CHEMICAL DEHALOGENATION (QUICK REFERENCE FACT SHEET)

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of remedy evaluation and selection under the Superfund program. his manual focuses on chemical dehalogenation treatability studies conducted in support of remedy selection that is conducted ...

  3. A comprehensive study on maxillofacial trauma conducted in Yamunanagar, India

    PubMed Central

    Bali, Rishi; Sharma, Parveen; Garg, Amandeep; Dhillon, Guneet

    2013-01-01

    Abstract: Background: The Department of Oral and Maxillofacial Surgery, D.A.V [C] Dental College and Hospital, Yamuna Nagar, Haryana, India conducted a study on patients with maxillofacial fractures in a time span of seven years (2003-2010). The purpose of this study was to evaluate their aetiology, incidence, patterns and different modalities employed for management. Methods: In this study, 740 patients with 1054 fractures were evaluated clinically and radiographically, based on which closed reduction and open reduction was undertaken. Review of patient records included: Age, sex, time, mechanism and etiology of injury, history of bleeding, unconsciousness and prior first aid, type of vehicle and use of preventive measures, type of fracture and treatment modalities. Results: Road traffic accidents accounted for highest number of fractures predominantly occurring in the age group of 21-30 years (38.3%)1,2. Males incurred more fractures with a male female ratio of 4.2: 1.Mandible was the most commonly fractured bone with parasymphysis being the commonest affected site.76.66% patients had associated head injury and 15.68 % had history of unconsciousness. Open reduction and internal fixation was the preferred modality for mandible whereas the mid face fractures were treated more often by closed methods. Conclusions: Injuries occurred more commonly in 20 – 40 age range with road traffic accident being the major etiological factor. Majority of the patients were driving two wheelers and most were under the effect of alcohol. Most of the injuries occurred during night and road traffic accidents (71.89%) were found to be the major etiological factor. Out of 532 road traffic accidents, 490 patients (66.2%) were on two wheelers, among whom 49(10%) were wearing helmet. In the mandible, fractures occurred most commonly in the parasymphyseal region (224, 30.2%), and out of the 314 fractures of the middle third showed, 155 (49.4%) ZMC. OPG was the most commonly advised X

  4. Nerve conduction studies in upper extremities: skin temperature corrections.

    PubMed

    Halar, E M; DeLisa, J A; Soine, T L

    1983-09-01

    The relationship of skin to near nerve (NN) temperature and to nerve conduction velocity (NCV) and distal latency (DL) was studied in 34 normal adult subjects before and after cooling both upper extremities. Median and ulnar motor and sensory NCV, DL, and NN temperature were determined at ambient temperature (mean X skin temp = 33 C) and after cooling, at approximately 26, 28, and 30 C of forearm skin temperature. Skin temperatures on the volar side of the forearm, wrist, palm, and fingers and NN temperature at the forearm, midpalm, and thenar or hypothenar eminence were compared with respective NCV and DL. Results showed a significant linear correlation between skin temperature and NN temperature at corresponding sites (r2 range, 0.4-0.84; p less than 0.005). Furthermore, both skin and NN temperatures correlated significantly with respective NCV and DL. Midline wrist skin temperature showed the best correlation to NCV and DL. Median motor and sensory NCV were altered 1.5 and 1.4m/sec/C degree and their DL 0.2 msec/C degree of wrist skin temperature change, respectively. Ulnar motor and sensory NCV were changed 2.1 and 1.6m/sec/C degree respectively, and 0.2 msec/C degree wrist temperature for motor and sensory DL. Average ambient skin temperature at the wrist (33 C) was used as a standard skin temperature in the temperature correction formula: NCV or DL(temp corrected) = CF(Tst degree - Tm degree) + obtained NCV or DL, where Tst = 33 C for wrist, Tm = the measured skin temperature, and CF = correction factor of tested nerve. Use of temperature correction formula for NCV and DL is suggested in patients with changed wrist skin temperature outside 29.6-36.4C temperature range. PMID:6615178

  5. Study of new proton conducting glasses for fuel cells

    NASA Astrophysics Data System (ADS)

    Tiple, S. R.; Deshpande, V. K.

    2015-08-01

    The glasses in the series (35-x) BaO:65 P2O5:x (NH4)2SO4 are synthesized and characterized by Tg, CTE, density and electrical conductivity measurements. The decrease in density and Tg is observed with addition of (NH4)2SO4. The increase in CTE compliments the observed variation in Tg. The protonic conductivity increases with addition of (NH4)2SO4 up to 7.5 mol% and decreases beyond this composition. The increase in the ratio of O/P, which in turn, creates more non-bridging oxygens, enhances the conductivity. Further, sulfur is mainly incorporated in sulfophosphate glasses as isolated SO42- group which also results in increase in conductivity. The glass with maximum conductivity [7.5(NH4)2SO4:27.5BaO:65 P2O5] is used to fabricate a fuel cell. It gives the power density of 12.43 μW/cm2. The power density of the fuel cell in the present work at room temperature is higher than that reported in literature at 473 K. The fuel cell has a potential of giving higher power density at higher temperature of 423 K.

  6. Electrical Characterization and Morphological Studies of Conducting Polymer Nanofibers

    NASA Technical Reports Server (NTRS)

    Pinto, N. J.; Zhou, Y. X.; Freitag, M.; Johnson, A. T.; MacDiarmid, A. G.; Mueller, C. H.; Theofylaktos, N.; Robinson, D. C.; Miranda, F. A.

    2003-01-01

    Doped polyaniline blended with poly(ethylene oxide) has been electrospun in air to give fibers with diameters in the range 3 nm 200 nm. These fibers were captured on wafers of degenerately doped Si/SiO2 by placing the wafer in the path of the fiber jet formed during the electrospinning process. Individual fibers were contacted using shadow mask evaporation and were also captured on prepatterned wafers. Fibers having diameters greater than 100 nm show a slight increase in the conductivity as compared to the bulk film, while fibers with diameters less than 30 nm had lower conductivity than the bulk. Data on Scanning Conductance Microscopy along the length of individual fibers will be presented. For fibers where the diameter was not uniform, we found that below a certain diameter ( approx.15 nm) the fiber was less conducting as compared to thicker diameter fibers. Dependence of the fiber conductivity on a gate bias is underway and these results will also be presented.

  7. Smoking Patterns, Attitudes and Motives: Unique Characteristics among 2-Year versus 4-Year College Students

    ERIC Educational Resources Information Center

    Berg, C. J.; An, L. C.; Thomas, J. L.; Lust, K. A.; Sanem, J. R.; Swan, D. W.; Ahluwalia, J. S.

    2011-01-01

    Given the previously documented higher rates of smoking among 2-year college students in comparison with 4-year university students, this study compares smoking patterns, attitudes and motives among 2-year and 4-year college students. Two thousand two hundred and sixty-five undergraduate students aged 18-25 years at a 2-year college and a 4-year…

  8. Materials characterization study of conductive flexible second surface mirrors

    NASA Technical Reports Server (NTRS)

    Levadou, F.; Bosma, S. J.; Paillous, A.

    1981-01-01

    The status of prequalification and qualification work on conductive flexible second surface mirrors is described. The basic material is FEP Teflon witn either aluminium or silver vacuum deposited reflectors. The top layer has been made conductive by deposition of layer of a indium oxide. The results of a prequalification program comprised of decontamination, humidity, thermal cycling, thermal shock and vibration tests are presented. Thermo-optical and electrical properties. The results of a prequalification program comprised of decontamination, humidity, thermal cycling, thermal shock and vibration tests are presented. Thermo-optical and electrical properties, the electrostatic behavior of the materials under simulated substorm environment and electrical conductivity at low temperatures are characterized. The effects of simulated ultra violet and particles irradiation on electrical and thermo-optical properties of the materials are also presented.

  9. Thermal conductivity of model zeolites: molecular dynamics simulation study

    NASA Astrophysics Data System (ADS)

    Murashov, Vladimir V.

    1999-02-01

    The thermal conductivity of model zeolites was investigated using non-equilibrium molecular dynamics calculations. This type of calculation was found to overestimate the thermal conductivity of low-density silica polymorphs. A better reproduction of the experimental results was found for zeolites, and this was related to the lower phonon mean free path. The thermal conductivity of framework silicates was shown to be determined primarily by the vibrations of the continuous oxygen sublattice. Thus, the most drastic suppression of the heat transfer was related to alterations of the O-O distances; for example, a sixfold reduction in thermal conductivity compared to that of siliceous LTA zeolite was found for LTA-A1PO4. Framework cations were shown to affect the heat transfer by changing the vibrational modes of the structural building units of the framework and non-framework counter-cations, by disturbing the oxygen sublattice locally and acting as Rayleigh and resonant scatterers. A model assuming the heat transfer to be due only to non-dispersive acoustic phonons failed to reproduce the dependence of the thermal conductivity on the mass of the cations and the unit-cell dimension, thus suggesting a more sophisticated mechanism of heat transfer to be operative in framework materials. The effect of non-framework non-ionic species on the thermal conductivity was shown to be determined by their effect on the characteristics of the oxygen framework vibrations. Thus, repulsive interactions between the oxygen sublattice and Xe8 clusters, reducing the anisotropy and anharmonicity of the oxygen vibrations, give rise to enhanced heat transfer in LTA-SiO2 at ambient conditions.

  10. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Foreign clinical studies not conducted under an....120 Foreign clinical studies not conducted under an IND. (a) Acceptance of studies. (1) FDA will... and well-conducted foreign clinical study not conducted under an IND, if the following conditions...

  11. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Foreign clinical studies not conducted under an....120 Foreign clinical studies not conducted under an IND. (a) Acceptance of studies. (1) FDA will... and well-conducted foreign clinical study not conducted under an IND, if the following conditions...

  12. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Foreign clinical studies not conducted under an....120 Foreign clinical studies not conducted under an IND. (a) Acceptance of studies. (1) FDA will... and well-conducted foreign clinical study not conducted under an IND, if the following conditions...

  13. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Foreign clinical studies not conducted under an....120 Foreign clinical studies not conducted under an IND. (a) Acceptance of studies. (1) FDA will... and well-conducted foreign clinical study not conducted under an IND, if the following conditions...

  14. Mössbauer study of conductive oxide glass

    NASA Astrophysics Data System (ADS)

    Matsuda, Koken; Kubuki, Shiro; Nishida, Tetsuaki

    2014-10-01

    Heat treatment of barium iron vanadate glass, BaO - Fe2O3- V2O5, at temperatures higher than crystallization temperature causes a marked decrease in resistivity (ρ) from several MΩcm to several Ωcm. 57Fe Mössbauer spectrum of heat-treated vanadate glass shows a marked decrease in quadrupole splitting (Δ) of FeIII, reflecting a structural relaxation, i.e., an increased symmetry of "distorted" FeO4 and VO4 tetrahedra which are connected to each other by sharing corner oxygen atoms. Structural relaxation of 3D-network of vanadate glass accompanies a decrease in the activation energy for the conduction, reflecting a decreased energy gap between the donor level and conduction band. A marked increase in the conductivity was observed in CuO- or Cu2O -containing barium iron vanadate glass after heat treatment at 450 °C for 30 min or more. "n-type semiconductor model combined with small polaron hopping theory" was proposed in order to explain the high conductivity.

  15. Ionic conductivity studies of gel polyelectrolyte based on ionic liquid

    NASA Astrophysics Data System (ADS)

    Cha, E. H.; Lim, S. A.; Park, J. H.; Kim, D. W.; Macfarlane, D. R.

    Novel lithium polyelectrolyte-ionic liquids have been prepared and characterized of their properties. Poly(lithium 2-acrylamido-2-methyl propanesulfonate) (PAMPSLi) and its copolymer with N-vinyl formamide (VF) also has been prepared as a copolymer. 1-Ethyl-3-methylimidazolium tricyanomethanide (emImTCM) and N, N-dimethyl- N-propyl- N-butyl ammonium tricyanomethanide (N 1134TCM) which are chosen because of the same with the anion of ionic liquid were prepared. The ionic conductivity of copolymer system (PAMPSLi/PVF/emImTCM: 5.43 × 10 -3 S cm -1 at 25 °C) exhibits about over four times higher than that of homopolymer system (PAMPSLi/emImTCM: 1.28 × 10 -3 S cm -1 at 25 °C). Introduction of vinyl formamide into the copolymer type can increase the dissociation of the lithium cations from the polymer backbone. The ionic conductivity of copolymer with emImTCM (PAMPSLi/PVF/emImTCM) exhibits the higher conductivity than that of PAMPSLi/PVF/N 1134TCM (2.48 × 10 -3 S cm -1). Because of using the polymerizable anion it is seen to maintain high flexibility of imidazolium cation effectively to exhibit the higher conductivity. And also the viscosity of emImTCM (19.56 cP) is lower than that of N 1134TCM (28.61 cP). Low viscosity leads to a fast rate of diffusion of redox species.

  16. Study on Thermal Conductivities of Aromatic Polyimide Aerogels.

    PubMed

    Feng, Junzong; Wang, Xin; Jiang, Yonggang; Du, Dongxuan; Feng, Jian

    2016-05-25

    Polyimide aerogels for low density thermal insulation materials were produced by 4,4'-diaminodiphenyl ether and 3,3',4,4'-biphenyltetracarboxylic dianhydride, cross-linked with 1,3,5-triaminophenoxybenzene. The densities of obtained polyimide aerogels are between 0.081 and 0.141 g cm(-3), and the specific surface areas are between 288 and 322 m(2) g(-1). The thermal conductivities were measured by a Hot Disk thermal constant analyzer. The value of the measured thermal conductivity under carbon dioxide atmosphere is lower than that under nitrogen atmosphere. Under pressure of 5 Pa at -130 °C, the thermal conductivity is the lowest, which is 8.42 mW (m K)(-1). The polyimide aerogels have lower conductivity [30.80 mW (m K)(-1)], compared to the value for other organic foams (polyurethane foam, phenolic foam, and polystyrene foam) with similar apparent densities under ambient pressure at 25 °C. The results indicate that polyimide aerogel is an ideal insulation material for aerospace and other applications. PMID:27149155

  17. Mössbauer study of conductive oxide glass

    SciTech Connect

    Matsuda, Koken; Kubuki, Shiro; Nishida, Tetsuaki

    2014-10-27

    Heat treatment of barium iron vanadate glass, BaO‐Fe{sub 2}O{sub 3}‐V{sub 2}O{sub 5}, at temperatures higher than crystallization temperature causes a marked decrease in resistivity (ρ) from several MΩcm to several Ωcm. {sup 57}Fe Mössbauer spectrum of heat-treated vanadate glass shows a marked decrease in quadrupole splitting (Δ) of Fe{sup III}, reflecting a structural relaxation, i.e., an increased symmetry of 'distorted' FeO{sub 4} and VO{sub 4} tetrahedra which are connected to each other by sharing corner oxygen atoms. Structural relaxation of 3D-network of vanadate glass accompanies a decrease in the activation energy for the conduction, reflecting a decreased energy gap between the donor level and conduction band. A marked increase in the conductivity was observed in CuO- or Cu{sub 2}O-containing barium iron vanadate glass after heat treatment at 450 °C for 30 min or more. 'n-type semiconductor model combined with small polaron hopping theory' was proposed in order to explain the high conductivity.

  18. Comparative study of ion conducting pathways in borate glasses

    SciTech Connect

    Hall, Andreas; Swenson, Jan; Adams, Stefan

    2006-11-01

    The conduction pathways in metal-halide doped silver, lithium, and sodium diborate glasses have been examined by bond valence analysis of reverse Monte Carlo (RMC) produced structural models of the glasses. Although all glass compositions have basically the same short-range structure of the boron-oxygen network, it is evident that the intermediate-range structure is strongly dependent on the type of mobile ion. The topography of the pathways and the coordination of the pathway sites differ distinctly between the three glass systems. The mobile silver ions in the AgI-doped glass tend to be mainly iodine-coordinated and travel in homogeneously distributed pathways located in salt-rich channels of the borate network. In the NaCl-doped glass, there is an inhomogeneous spatial distribution of pathways that reflects the inhomogeneous introduction of salt ions into the glass. However, since the salt clusters are not connected, no long-range conduction pathways are formed without including also oxygen-rich regions. The pathways in the LiCl-doped glass are slightly more evenly distributed compared to the NaCl-doped glass (but not as ordered as in the AgI-doped glass), and the regions of mainly oxygen-coordinated pathway sites are of higher importance for the long-range migration. In order to more accurately investigate how these differences in the intermediate-range order of the glasses affect the ionic conductivity, we have compared the realistic structure models to more or less randomized structures. An important conclusion from this comparison is that we find no evidence that a pronounced intermediate-range order in the atomic structure or in the network of conduction pathways, as in the AgI-doped glass, is beneficial for the dc conductivity.

  19. Spectroscopic ellipsometry study of novel nanostructured transparent conducting oxide structures

    NASA Astrophysics Data System (ADS)

    Khosroabadi, Akram A.; Norwood, R. A.

    2013-02-01

    Spectroscopic ellipsometry has been used to find the optical constants, including refractive index, extinction coefficient, thickness and volume fraction of nanostructured transparent conducting oxides including indium tin oxide (ITO) and indium zinc oxide (IZO). We observed sharp features in the ellipsometry data, with the spectral peaks and positions depending on the nanostructure dimensions and material. A superposition of Lorentzian oscillators and the effective medium approximation has been applied to determine the volume ratio of voids and nanopillars, thereby providing the effective optical constants.

  20. Nuclear Spin Lattice Relaxation and Conductivity Studies of the Non-Arrhenius Conductivity Behavior in Lithium Fast Ion Conducting Sulfide Glasses

    SciTech Connect

    Benjamin Michael Meyer

    2003-05-31

    As time progresses, the world is using up more of the planet's natural resources. Without technological advances, the day will eventually arrive when these natural resources will no longer be sufficient to supply all of the energy needs. As a result, society is seeing a push for the development of alternative fuel sources such as wind power, solar power, fuel cells, and etc. These pursuits are even occurring in the state of Iowa with increasing social pressure to incorporate larger percentages of ethanol in gasoline. Consumers are increasingly demanding that energy sources be more powerful, more durable, and, ultimately, more cost efficient. Fast Ionic Conducting (FIC) glasses are a material that offers great potential for the development of new batteries and/or fuel cells to help inspire the energy density of battery power supplies. This dissertation probes the mechanisms by which ions conduct in these glasses. A variety of different experimental techniques give a better understanding of the interesting materials science taking place within these systems. This dissertation discusses Nuclear Magnetic Resonance (NMR) techniques performed on FIC glasses over the past few years. These NMR results have been complimented with other measurement techniques, primarily impedance spectroscopy, to develop models that describe the mechanisms by which ionic conduction takes place and the dependence of the ion dynamics on the local structure of the glass. The aim of these measurements was to probe the cause of a non-Arrhenius behavior of the conductivity which has been seen at high temperatures in the silver thio-borosilicate glasses. One aspect that will be addressed is if this behavior is unique to silver containing fast ion conducting glasses. more specifically, this study will determine if a non-Arrhenius correlation time, {tau}, can be observed in the Nuclear Spin Lattice Relaxation (NSLR) measurements. If so, then can this behavior be modeled with a new single distribution

  1. Ionic Conductivity And Structural Relaxation Studies on Lithium Niobophosphate Glass

    SciTech Connect

    Dabas, Prashant; Hariharan, K.

    2011-07-15

    Niobium pentoxide (Nb{sub 2}O{sub 5}) increases the chemical and thermal stability of otherwise hygroscopic alkali phosphate glasses and also enhances the conduction characteristics. Ion dynamics and structural relaxation have been investigated for mol%50Li{sub 2}0-45P{sub 2}0{sub 5}-5Nb{sub 2}O{sub 5}. The non-linearity parameter 'x' in the Tool-Narayanaswamy model is evaluated using the dependence of fictive and glass transition temperatures on the cooling and heating rates.

  2. Structural and AC conductivity study of CdTe nanomaterials

    NASA Astrophysics Data System (ADS)

    Das, Sayantani; Banerjee, Sourish; Sinha, T. P.

    2016-04-01

    Cadmium telluride (CdTe) nanomaterials have been synthesized by soft chemical route using mercapto ethanol as a capping agent. Crystallization temperature of the sample is investigated using differential scanning calorimeter. X-ray diffraction and transmission electron microscope measurements show that the prepared sample belongs to cubic structure with the average particle size of 20 nm. Impedance spectroscopy is applied to investigate the dielectric relaxation of the sample in a temperature range from 313 to 593 K and in a frequency range from 42 Hz to 1.1 MHz. The complex impedance plane plot has been analyzed by an equivalent circuit consisting of two serially connected R-CPE units, each containing a resistance (R) and a constant phase element (CPE). Dielectric relaxation peaks are observed in the imaginary parts of the spectra. The frequency dependence of real and imaginary parts of dielectric permittivity is analyzed using modified Cole-Cole equation. The temperature dependence relaxation time is found to obey the Arrhenius law having activation energy ~0.704 eV. The frequency dependent conductivity spectra are found to follow the power law. The frequency dependence ac conductivity is analyzed by power law.

  3. Scanning Ion Conductance Microscopy for Studying Biological Samples

    PubMed Central

    Happel, Patrick; Thatenhorst, Denis; Dietzel, Irmgard D.

    2012-01-01

    Scanning ion conductance microscopy (SICM) is a scanning probe technique that utilizes the increase in access resistance that occurs if an electrolyte filled glass micro-pipette is approached towards a poorly conducting surface. Since an increase in resistance can be monitored before the physical contact between scanning probe tip and sample, this technique is particularly useful to investigate the topography of delicate samples such as living cells. SICM has shown its potential in various applications such as high resolution and long-time imaging of living cells or the determination of local changes in cellular volume. Furthermore, SICM has been combined with various techniques such as fluorescence microscopy or patch clamping to reveal localized information about proteins or protein functions. This review details the various advantages and pitfalls of SICM and provides an overview of the recent developments and applications of SICM in biological imaging. Furthermore, we show that in principle, a combination of SICM and ion selective micro-electrodes enables one to monitor the local ion activity surrounding a living cell. PMID:23202197

  4. Scanning ion conductance microscopy studies of amyloid fibrils at nanoscale

    NASA Astrophysics Data System (ADS)

    Zhang, Shuai; Cho, Sang-Joon; Busuttil, Katerina; Wang, Chen; Besenbacher, Flemming; Dong, Mingdong

    2012-05-01

    Atomic force microscopy (AFM) has developed to become a very versatile nano-scale technique to reveal the three-dimensional (3D) morphology of amyloid aggregates under physiological conditions. However, the imaging principle of AFM is based on measuring the `force' between a sharp tip and a given nanostructure, which may cause mechanical deformation of relatively soft objects. To avoid the deformation, scanning ion conductance microscopy (SICM) is an alternative scanning probe microscopy technique, operating with alternating current mode. Here we can indeed reveal the 3D morphology of amyloid fibrils and it is capable of exploring proteins with nanoscale resolution. Compared with conventional AFM, we show that SICM can provide precise height measurements of amyloid protein aggregates, a feature that enables us to obtain unique insight into the detailed nucleation and growth mechanisms behind amyloid self-assembly.

  5. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF... request assistance to conduct a feasibility study? To request assistance to conduct a feasibility study... submit a full proposal to conduct a feasibility study in response to the program announcement,...

  6. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF... request assistance to conduct a feasibility study? To request assistance to conduct a feasibility study... submit a full proposal to conduct a feasibility study in response to the program announcement,...

  7. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF... request assistance to conduct a feasibility study? To request assistance to conduct a feasibility study... submit a full proposal to conduct a feasibility study in response to the program announcement,...

  8. Mechanistic study of silver nanoparticle formation on conducting polymer surfaces.

    PubMed

    Mack, Nathan H; Bailey, James A; Doorn, Stephen K; Chen, Chien-An; Gau, Han-Mou; Xu, Ping; Williams, Darrick J; Akhadov, Elshan A; Wang, Hsing-Lin

    2011-04-19

    Conducting polymer (polyaniline) sheets are shown to be active substrates to promote the growth of nanostructured silver thin films with highly tunable morphologies. Using the spontaneous electroless deposition of silver, we show that a range of nanostructured metallic features can be controllably and reproducibly formed over large surface areas. The structural morphology of the resulting metal-polymer nanocomposite is demonstrated to be sensitive to experimental parameters such as ion concentration, temperature, and polymer processing and can range from densely packed oblate nanosheets to bulk crystalline metals. The deposition mechanisms are explained using a diffusion-limited aggregation (DLA) model to describe the semi-fractal-like growth of the metal nanostructures. We find these composite films to exhibit strong surface-enhanced Raman (SERS) activity, and the nanostructured features are optimized with respect to SERS activity using a self-assembled monolayer of mercapto-benzoic acid as a model Raman reporter. SERS enhancements are estimated to be on the order of 10(7). Through micro-Raman SERS mapping, these materials are shown to exhibit uniform SERS responses over macroscopic areas. These metal-polymer nanocomposites benefit from the underlying polymer's processability to yield SERS-active materials of almost limitless shape and size and show significant promise for future SERS-based sensing and detection schemes. PMID:21434643

  9. Conducting influenza virus pathogenesis studies in avian species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian infection studies with influenza A are an important means of assessing host susceptibility, viral pathogenesis, host responses to infection, mechanisms of transmission and viral pathotype. Complex systems and natural settings may also be explored with carefully designed infection studies. In ...

  10. Recommendations for conducting controlled clinical studies of dental restorative materials.

    PubMed

    Hickel, R; Roulet, J-F; Bayne, S; Heintze, S D; Mjör, I A; Peters, M; Rousson, V; Randall, R; Schmalz, G; Tyas, M; Vanherle, G

    2007-03-01

    About 35 years ago, Ryge provided a practical approach to evaluation of clinical performance of restorative materials. This systematic approach was soon universally accepted. While that methodology has served us well, a large number of scientific methodologies and more detailed questions have arisen that require more rigor. Current restorative materials have vastly improved clinical performance and any changes over time are not easily detected by the limited sensitivity of the Ryge criteria in short term clinical investigations. However, the clinical evaluation of restorations not only involves the restorative material per se but also different operative techniques. For instance, a composite resin may show good longevity data when applied in conventional cavities but not in modified operative approaches. Insensitivity, combined with the continually evolving and non-standard investigator modifications of the categories, scales, and reporting methods, has created a body of literature that is extremely difficult to meaningfully interpret. In many cases, the insensitivity of the original Ryge methods is misinterpreted as good clinical performance. While there are many good features of the original system, it is now time to move to a more contemporary one. The current review approaches this challenge in two ways: (1) a proposal for a modern clinical testing protocol for controlled clinical trials, and (2) an in-depth discussion of relevant clinical evaluation parameters, providing 84 references that are primarily related to issues or problems for clinical research trials. Together, these two parts offer a standard for the clinical testing of restorative materials/procedures and provide significant guidance for research teams in the design and conduct of contemporary clinical trials. Part 1 of the review considers the recruitment of subjects, restorations per subject, clinical events, validity versus bias, legal and regulatory aspects, rationales for clinical trial

  11. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Conduct of a nonclinical laboratory study. 58.130 Section 58.130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL GOOD LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Protocol for and Conduct of a Nonclinical Laboratory Study § 58.130 Conduct of...

  12. A protocol for conducting rainfall simulation to study soil runoff

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial ur...

  13. Study of electrical resistivity and thermal conductivity into neutral plasma

    SciTech Connect

    Nath, G. Rout, R. K.

    2015-07-31

    The major portion of the bulk plasma in magnetospheric space, interplanetary plasma belts and the solar winds contain neutral particles. Evidently these neutral particles undergo binary collisions with the charged particles and among themselves so as to contribute significantly to the transport and diffusion process in a singly charged electron – ion magnetoplasma. The effects of the neutral particles collisions on various diffusion transport coefficients are studied for magnetised electron-ion plasma and appropriately modified coefficients are derived analytically. The results reveal that these coefficients increase significantly owing to the effect of the charge -neutral and neutral-neutral collisions.

  14. Multicollinearity in Regression Analyses Conducted in Epidemiologic Studies

    PubMed Central

    Vatcheva, Kristina P.; Lee, MinJae; McCormick, Joseph B.; Rahbar, Mohammad H.

    2016-01-01

    The adverse impact of ignoring multicollinearity on findings and data interpretation in regression analysis is very well documented in the statistical literature. The failure to identify and report multicollinearity could result in misleading interpretations of the results. A review of epidemiological literature in PubMed from January 2004 to December 2013, illustrated the need for a greater attention to identifying and minimizing the effect of multicollinearity in analysis of data from epidemiologic studies. We used simulated datasets and real life data from the Cameron County Hispanic Cohort to demonstrate the adverse effects of multicollinearity in the regression analysis and encourage researchers to consider the diagnostic for multicollinearity as one of the steps in regression analysis. PMID:27274911

  15. Mutagenic activity of paracetamol. A study conducted on volunteers.

    PubMed

    Srám, R J; Kocisová, J; Rössner, P; Binková, B; Topinka, J; Bavorová, H

    1990-01-01

    The mutagenic activity of paracetamol (PC) was studied on a group of healthy persons (3 men, 8 women) after the simultaneous administration of 3 X 1000 mg of PC and an identical dose of PC + 1000 mg of ascorbic acid within a period of 8 hours. Blood sample tests were made at intervals of 0, 24, 72 and 168 hours. A cytogenetic analysis showed that in 24 hours PC had increased the aberrant cell frequency to 2.77 +/- 0.37 per cent as distinct from 1.68 +/- 0.30 per cent (p less than 0.05) prior to the drug. In 72 hours, the rate of buccal mucosa micronuclei had risen to 0.38 +/- 0.07% against 0.19 +/- 0.06% prior to PC (p less than 0.01). Unscheduled DNA synthesis in peripheral lymphocytes had dropped to T/C = 2.06 +/- 0.54 (p less than 0.01) against 3.16 +/- 0.84 before PC. The lipid peroxidation level in the plasma remained unchanged. Ascorbic acid administered simultaneously with PC had no effect on the changes observed. A further follow-up of other PC side effects is recommended. PMID:2245754

  16. Mössbauer spectroscopy studies of selected conducting polypyrroles

    NASA Astrophysics Data System (ADS)

    Proń, A.; Kucharski, Z.; Budrowski, C.; Zagórska, M.; Krichene, S.; Suwalski, J.; Dehe, G.; Lefrant, S.

    1985-12-01

    Polypyrrole obtained by chemical oxidation of pyrrole in ethanol-water solution containing FeCl3 can be reduced chemically in Na+Naph-/THF solution and then reoxidized with FeCl3, SnCl4, and SbCl5. 57Fe and 119Sn Mössbauer spectra of the reaction products show only one type of iron and tin with Mössbauer parameters characteristic of FeCl-4 and SnCl-5. In the case of the oxidation with SbCl5, two nonequivalent antimony nuclei have been detected by 121Sb. The calculated isomer shift and quadrupole splitting values are consistent with SbCl-6 and SbCl3. The resonant absorption in all three systems studied is strongly temperature dependent and can be observed only at temperatures significantly lower than RT. This behavior indicates a low Mössbauer lattice temperature and an extremely loose bonding between the inserted anions and polymer chains.

  17. Parametric Study Conducted of Rocket- Based, Combined-Cycle Nozzles

    NASA Technical Reports Server (NTRS)

    Steffen, Christopher J., Jr.; Smith, Timothy D.

    1998-01-01

    Having reached the end of the 20th century, our society is quite familiar with the many benefits of recycling and reusing the products of civilization. The high-technology world of aerospace vehicle design is no exception. Because of the many potential economic benefits of reusable launch vehicles, NASA is aggressively pursuing this technology on several fronts. One of the most promising technologies receiving renewed attention is Rocket-Based, Combined-Cycle (RBCC) propulsion. This propulsion method combines many of the efficiencies of high-performance jet aircraft with the power and high-altitude capability of rocket engines. The goal of the present work at the NASA Lewis Research Center is to further understand the complex fluid physics within RBCC engines that govern system performance. This work is being performed in support of NASA's Advanced Reusable Technologies program. A robust RBCC engine design optimization demands further investigation of the subsystem performance of the engine's complex propulsion cycles. The RBCC propulsion system under consideration at Lewis is defined by four modes of operation in a singlestage- to-orbit configuration. In the first mode, the engine functions as a rocket-driven ejector. When the rocket engine is switched off, subsonic combustion (mode 2) is present in the ramjet mode. As the vehicle continues to accelerate, supersonic combustion (mode 3) occurs in the ramjet mode. Finally, as the edge of the atmosphere is approached and the engine inlet is closed off, the rocket is reignited and the final accent to orbit is undertaken in an all-rocket mode (mode 4). The performance of this fourth and final mode is the subject of this present study. Performance is being monitored in terms of the amount of thrust generated from a given amount of propellant.

  18. Probabilistic Study Conducted on Sensor-Based Engine Life Calculation

    NASA Technical Reports Server (NTRS)

    Guo, Ten-Huei

    2004-01-01

    Turbine engine life management is a very complicated process to ensure the safe operation of an engine subjected to complex usage. The challenge of life management is to find a reasonable compromise between the safe operation and the maximum usage of critical parts to reduce maintenance costs. The commonly used "cycle count" approach does not take the engine operation conditions into account, and it oversimplifies the calculation of the life usage. Because of the shortcomings, many engine components are regularly pulled for maintenance before their usable life is over. And, if an engine has been running regularly under more severe conditions, components might not be taken out of service before they exceed their designed risk of failure. The NASA Glenn Research Center and its industrial and academic partners have been using measurable parameters to improve engine life estimation. This study was based on the Monte Carlo simulation of 5000 typical flights under various operating conditions. First a closed-loop engine model was developed to simulate the engine operation across the mission profile and a thermomechanical fatigue (TMF) damage model was used to calculate the actual damage during takeoff, where the maximum TMF accumulates. Next, a Weibull distribution was used to estimate the implied probability of failure for a given accumulated cycle count. Monte Carlo simulations were then employed to find the profiles of the TMF damage under different operating assumptions including parameter uncertainties. Finally, probabilities of failure for different operating conditions were analyzed to demonstrate the importance of a sensor-based damage calculation in order to better manage the risk of failure and on-wing life.

  19. HIV-Exposed Uninfected Infants Show Robust Memory B-Cell Responses in Spite of a Delayed Accumulation of Memory B Cells: an Observational Study in the First 2 Years of Life.

    PubMed

    Nduati, Eunice W; Nkumama, Irene N; Gambo, Faith K; Muema, Daniel M; Knight, Miguel G; Hassan, Amin S; Jahangir, Margaret N; Etyang, Timothy J; Berkley, James A; Urban, Britta C

    2016-07-01

    Improved HIV care has led to an increase in the number of HIV-exposed uninfected (HEU) infants born to HIV-infected women. Although they are uninfected, these infants experience increased morbidity and mortality. One explanation may be that their developing immune system is altered by HIV exposure, predisposing them to increased postnatal infections. We explored the impact of HIV exposure on the B-cell compartment by determining the B-cell subset distribution, the frequency of common vaccine antigen-specific memory B cells (MBCs), and the levels of antibodies to the respective antigens in HEU and HIV-unexposed uninfected (HUU) infants born to uninfected mothers, using flow cytometry, a B-cell enzyme-linked immunosorbent spot assay, and an enzyme-linked immunosorbent assay, respectively, during the first 2 years of life. For the majority of the B-cell subsets, there were no differences between HEU and HUU infants. However, HIV exposure was associated with a lower proportion of B cells in general and MBCs in particular, largely due to a lower proportion of unswitched memory B cells. This reduction was maintained even after correcting for age. These phenotypic differences in the MBC compartment did not affect the ability of HEU infants to generate recall responses to previously encountered antigens or reduce the antigen-specific antibody levels at 18 months of life. Although HIV exposure was associated with a transient reduction in the proportion of MBCs, we found that the ability of HEU infants to mount robust MBC and serological responses was unaffected. PMID:27170641

  20. The association of maternal vitamin D status with infant birth outcomes, postnatal growth and adiposity in the first 2 years of life in a multi-ethnic Asian population: the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort study.

    PubMed

    Ong, Yi Lin; Quah, Phaik Ling; Tint, Mya Thway; Aris, Izzuddin M; Chen, Ling Wei; van Dam, Rob M; Heppe, Denise; Saw, Seang-Mei; Godfrey, Keith M; Gluckman, Peter D; Chong, Yap Seng; Yap, Fabian; Lee, Yung Seng; Foong-Fong Chong, Mary

    2016-08-01

    Maternal vitamin D status during pregnancy has been associated with infant birth and postnatal growth outcomes, but reported findings have been inconsistent, especially in relation to postnatal growth and adiposity outcomes. In a mother-offspring cohort in Singapore, maternal plasma vitamin D was measured between 26 and 28 weeks of gestation, and anthropometric measurements were obtained from singleton offspring during the first 2 years of life with 3-month follow-up intervals to examine birth, growth and adiposity outcomes. Associations were analysed using multivariable linear regression. Of a total of 910 mothers, 13·2 % were vitamin D deficient (<50 nmol/l) and 26·5 % were insufficient (50-75 nmol/l). After adjustment for potential confounders and multiple testing, no statistically significant associations were observed between maternal vitamin D status and any of the birth outcomes - small for gestational age (OR 1·00; 95 % CI 0·56, 1·79) and pre-term birth (OR 1·16; 95 % CI 0·64, 2·11) - growth outcomes - weight-for-age z-scores, length-for-age z-scores, circumferences of the head, abdomen and mid-arm at birth or postnatally - and adiposity outcomes - BMI, and skinfold thickness (triceps, biceps and subscapular) at birth or postnatally. Maternal vitamin D status in pregnancy did not influence infant birth outcomes, postnatal growth and adiposity outcomes in this cohort, perhaps due to the low prevalence (1·6 % of the cohort) of severe maternal vitamin D deficiency (defined as of <30·0 nmol/l) in our population. PMID:27339329

  1. HIV-Exposed Uninfected Infants Show Robust Memory B-Cell Responses in Spite of a Delayed Accumulation of Memory B Cells: an Observational Study in the First 2 Years of Life

    PubMed Central

    Nkumama, Irene N.; Gambo, Faith K.; Muema, Daniel M.; Hassan, Amin S.; Jahangir, Margaret N.; Etyang, Timothy J.; Berkley, James A.; Urban, Britta C.

    2016-01-01

    Improved HIV care has led to an increase in the number of HIV-exposed uninfected (HEU) infants born to HIV-infected women. Although they are uninfected, these infants experience increased morbidity and mortality. One explanation may be that their developing immune system is altered by HIV exposure, predisposing them to increased postnatal infections. We explored the impact of HIV exposure on the B-cell compartment by determining the B-cell subset distribution, the frequency of common vaccine antigen-specific memory B cells (MBCs), and the levels of antibodies to the respective antigens in HEU and HIV-unexposed uninfected (HUU) infants born to uninfected mothers, using flow cytometry, a B-cell enzyme-linked immunosorbent spot assay, and an enzyme-linked immunosorbent assay, respectively, during the first 2 years of life. For the majority of the B-cell subsets, there were no differences between HEU and HUU infants. However, HIV exposure was associated with a lower proportion of B cells in general and MBCs in particular, largely due to a lower proportion of unswitched memory B cells. This reduction was maintained even after correcting for age. These phenotypic differences in the MBC compartment did not affect the ability of HEU infants to generate recall responses to previously encountered antigens or reduce the antigen-specific antibody levels at 18 months of life. Although HIV exposure was associated with a transient reduction in the proportion of MBCs, we found that the ability of HEU infants to mount robust MBC and serological responses was unaffected. PMID:27170641

  2. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will be... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false Conduct of feasibility... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An...

  3. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will be... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true Conduct of feasibility... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An...

  4. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will be... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true Conduct of feasibility... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An...

  5. Design and Conduct of the CALERIE Study: Comprehensive Assessment of the Long-term Effects of Reducing Intake of Energy

    PubMed Central

    Bales, Connie W.; Ravussin, Eric; Redman, Leanne M.; Holloszy, John O.; Racette, Susan B.; Roberts, Susan B.; Das, Sai Krupa; Romashkan, Sergei; Galan, Katherine M.; Hadley, Evan C.; Kraus, William E.

    2011-01-01

    Background. In a robust and consistent manner, sustained caloric restriction (CR) has been shown to retard the aging process in a variety of animal species. Nonhuman primate studies suggest that CR may have similar effects in longer-lived species. The CALERIE (Comprehensive Assessment of the Long-term Effects of Reducing Intake of Energy) research program is the first systematic investigation of CR in nonobese human beings. In the phase 2 study, it is hypothesized that 2 years of sustained CR, involving a 25% reduction of ad libitum energy intake, results in beneficial effects similar to those observed in animal studies. This article presents the design and implementation of this study. Methods. The study is a multicenter, parallel-group, randomized controlled trial. A sample of 225 participants (22.0 ≤ body mass index [BMI] < 28.0 kg/m2) is being enrolled with 2:1 allocation to CR. Results. An intensive dietary and behavioral intervention was developed to achieve 25% CR and sustain it over the 2 years. Adherence is monitored using a doubly labeled water technique. Primary outcomes are resting metabolic rate and core temperature, and are assessed at baseline and at 6-month intervals. Secondary outcomes address oxyradical formation, cardiovascular risk markers, insulin sensitivity and secretion, immune function, neuroendocrine function, quality of life and cognitive function. Biologic materials are stored in a central repository. Conclusions. An intricate protocol has been developed to conduct this study. Procedures have been implemented to safeguard the integrity of the data and the conclusions drawn. The results will provide insight into the detrimental changes associated with the human aging process and how CR mitigates these effects. PMID:20923909

  6. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false How will a feasibility study be conducted... Studies § 404.47 How will a feasibility study be conducted under this program? Feasibility studies will be... feasibility study, including the Principles and Guidelines (incorporated by reference at § 404.4). You...

  7. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false How will a feasibility study be conducted... Studies § 404.47 How will a feasibility study be conducted under this program? Feasibility studies will be... feasibility study, including the Principles and Guidelines (incorporated by reference at § 404.4). You...

  8. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true How will a feasibility study be conducted... Studies § 404.47 How will a feasibility study be conducted under this program? Feasibility studies will be... feasibility study, including the Principles and Guidelines (incorporated by reference at § 404.4). You...

  9. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false How will a feasibility study be conducted... Studies § 404.47 How will a feasibility study be conducted under this program? Feasibility studies will be... feasibility study, including the Principles and Guidelines (incorporated by reference at § 404.4). You...

  10. Clinical outcomes of pars plicata anterior vitrectomy: 2-year results

    PubMed Central

    Narang, Priya; Agarwal, Amar

    2015-01-01

    Purpose: To demonstrate the safety and outcome of a surgical approach that uses pars plicata site for anterior vitrectomy during phacoemulsification procedure complicated by posterior capsule rupture and residual cortical matter. Design: Single center, retrospective, interventional, noncomparative study. Materials and Methods: Medical records of a consecutive series of 35 eyes of 35 patients who underwent pars plicata anterior vitrectomy (PPAV) were reviewed. The main outcome measures were corrected and uncorrected distance visual acuity (CDVA, UDVA), early and late postoperative complications and intraocular pressure (IOP). Ultrasound biomicroscopic (UBM) evaluation of sclerotomy site and spectral domain optical coherence tomography analysis for central macular thickness (CMT) was performed. The final visual outcome at 2 years was evaluated. Results: At 2 years follow-up, the mean postoperative UDVA (logarithm of the minimum angle of resolution [logMAR]) and CDVA (logMAR) was 0.49 ± 0.26 and 0.19 ± 0.14, respectively. There was no significant change in the IOP (P = 0.061) and the mean CMT at 2 years was 192.5 ± 5.54 μm. The postoperative UBM image of the sclerotomy site at 8 weeks demonstrated a clear wound without any vitreous adhesion or incarceration. Intraoperative hyphema was seen in 1 (2.8%) case and postoperative uveitis was seen in 2 (5.7%) cases, which resolved with medications. No case of an iatrogenic retinal break or retinal detachment was reported. Conclusions: PPAV enables a closed chamber approach, allows thorough cleanup of vitreous in the pupillary plane and anterior chamber and affords better access to the subincisional and retropupillary cortical remnant with a significant visual outcome and an acceptable complication rate. PMID:26632124

  11. Infantile Amnesia across the Years: A 2-Year Follow-Up of Children's Earliest Memories

    ERIC Educational Resources Information Center

    Peterson, Carole; Warren, Kelly L.; Short, Megan M.

    2011-01-01

    Although infantile amnesia has been investigated for many years in adults, only recently has it been investigated in children. This study was a 2-year follow-up and extension of an earlier study. Children (4-13 years old) were asked initially and 2 years later for their earliest 3 memories. At follow-up, their age at the time of these memories…

  12. Chief Student Affairs Officers in 2-Year Colleges: Their Demographics and Educational Backgrounds

    ERIC Educational Resources Information Center

    Keim, Marybelle C.

    2008-01-01

    The purpose of this study was to determine demographics and educational backgrounds of chief student affairs officers (CSAOs) in public 2-year colleges. Using systematic sampling techniques, 300 2-year colleges were selected from the AACC Membership Directory for inclusion in the study. Each college's website was visited to determine the name of…

  13. Clinical neuroprediction: Amygdala reactivity predicts depressive symptoms 2 years later.

    PubMed

    Mattson, Whitney I; Hyde, Luke W; Shaw, Daniel S; Forbes, Erika E; Monk, Christopher S

    2016-06-01

    Depression is linked to increased amygdala activation to neutral and negatively valenced facial expressions. Amygdala activation may be predictive of changes in depressive symptoms over time. However, most studies in this area have focused on small, predominantly female and homogenous clinical samples. Studies are needed to examine how amygdala reactivity relates to the course of depressive symptoms dimensionally, prospectively and in populations diverse in gender, race and socioeconomic status. A total of 156 men from predominately low-income backgrounds completed an fMRI task where they viewed emotional facial expressions. Left and right amygdala reactivity to neutral, but not angry or fearful, facial expressions relative to a non-face baseline at age 20 predicted greater depressive symptoms 2 years later, controlling for age 20 depressive symptoms. Heightened bilateral amygdala reactivity to neutral facial expressions predicted increases in depressive symptoms 2 years later in a large community sample. Neutral facial expressions are affectively ambiguous and a tendency to interpret these stimuli negatively may reflect to cognitive biases that lead to increases in depressive symptoms over time. Individual differences in amygdala reactivity to neutral facial expressions appear to identify those at most risk for a more problematic course of depressive symptoms across time. PMID:26865423

  14. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will...

  15. A Collection of Studies Conducted in Education about "Global Warming" Problem

    ERIC Educational Resources Information Center

    Bozdogan, Aykut Emre

    2011-01-01

    The studies global warming problem conducted in education discipline in the world and in Turkey were analysed for this study. The literature was reviewed extensively especially through the articles in the indexed journals of Ebsco Host, Science Direct, Taylor and Francis and Web of Science databases and this study was conducted according to the…

  16. 41 CFR 101-5.104-6 - Conduct of feasibility studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... studies. 101-5.104-6 Section 101-5.104-6 Public Contracts and Property Management Federal Property... FEDERAL BUILDINGS AND COMPLEXES 5.1-General § 101-5.104-6 Conduct of feasibility studies. An initial... and detailed procedures to be followed in the conduct of each feasibility study. Arrangements will...

  17. 21 CFR 58.130 - Conduct of a nonclinical laboratory study.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... laboratory study shall be conducted in accordance with the protocol. (b) The test systems shall be monitored in conformity with the protocol. (c) Specimens shall be identified by test system, study, nature, and... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Conduct of a nonclinical laboratory study....

  18. Interstitial Lung Disease in Children Younger Than 2 Years.

    PubMed

    Spagnolo, Paolo; Bush, Andrew

    2016-06-01

    Childhood interstitial lung disease (chILD) represents a highly heterogeneous group of rare disorders associated with substantial morbidity and mortality. Although our understanding of chILD remains limited, important advances have recently been made, the most important being probably the appreciation that disorders that present in early life are distinct from those occurring in older children and adults, albeit with some overlap. chILD manifests with diffuse pulmonary infiltrates and nonspecific respiratory signs and symptoms, making exclusion of common conditions presenting in a similar fashion an essential preliminary step. Subsequently, a systematic approach to diagnosis includes a careful history and physical examination, computed tomography of the chest, and some or all of bronchoscopy with bronchoalveolar lavage, genetic testing, and if diagnostic uncertainty persists, lung biopsy. This review focuses on chILD presenting in infants younger than 2 years of age and discusses recent advances in the classification, diagnostic approach, and management of chILD in this age range. We describe novel genetic entities, along with initiatives that aim at collecting clinical data and biologic samples from carefully characterized patients in a prospective and standardized fashion. Early referral to expert centers and timely diagnosis may have important implications for patient management and prognosis, but effective therapies are often lacking. Following massive efforts, international collaborations among the key stakeholders are finally starting to be in place. These have allowed the setting up and conducting of the first randomized controlled trial of therapeutic interventions in patients with chILD. PMID:27245831

  19. Rapid fast-mapping abilities in 2-year-olds.

    PubMed

    Spiegel, Chad; Halberda, Justin

    2011-05-01

    Learning a new word consists of two primary tasks that have often been conflated into a single process: referent selection, in which a child must determine the correct referent of a novel label, and referent retention, which is the ability to store this newly formed label-object mapping in memory for later use. In addition, children must be capable of performing these tasks rapidly and repeatedly as they are frequently exposed to novel words during the course of natural conversation. Here we used a preferential pointing task to investigate 2-year-olds' (N=72) ability to infer the referent of a novel noun from a single ambiguous exposure and their ability to retain this mapping over time. Children were asked to identify the referent of a novel label on six critical trials distributed throughout the course of a 10-min study involving many familiar and novel objects. On these critical trials, images of a known object and a novel object (e.g., a ball and a nameless artifact constructed in the laboratory) appeared on two computer screens and a voice asked children to "point at the _____ [e.g., glark]." Following label onset, children were allowed only 3s during which to infer the correct referent, point at it, and potentially store this new word-object mapping. In a final posttest trial, all previously labeled novel objects appeared and children were asked to point to one of them (e.g., "Can you find the glark?"). To succeed, children needed to have initially mapped the novel labels correctly and retained these mappings over the course of the study. Despite the difficult demands of the current task, children successfully identified the target object on the retention trial. We conclude that 2-year-olds are able to fast map novel nouns during a brief single exposure under ambiguous labeling conditions. PMID:21145067

  20. Medical Care and Your 1- to 2-Year-Old

    MedlinePlus

    ... Zika & Pregnancy Medical Care and Your 1- to 2-Year-Old KidsHealth > For Parents > Medical Care and Your 1- to 2-Year-Old Print A A A Text Size ... Following simple instructions? Saying a few words? Combining two words by age 2? The doctor may ask ...

  1. Reduced thermal conductivity of a nanoparticle decorated nanowire: A non-equilibrium molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Masnoon, Ahmed Shafkat; Bipasha, Ferdaushi Alam; Morshed, A. K. M. M.

    2016-07-01

    The effect of nanoparticles decoration on the thermal conductivity of a nanowire is studied using Non Equilibrium Molecular Dynamics (NEMD) simulation. The simulation was conducted using simplified molecular model with Lennard-Jones potential. Argon-like solid was used as the material for both the nanowire and nanoparticles. Nanoparticles were placed on the surface of the nanowire and also embedded inside the structure. Non-equilibrium molecular dynamics simulation was conducted by imposing temperature gradient along the length of the nanowire and thermal conductivity of the nanowire was calculated. Nanowire without any nanoparticles was used as the baseline data. Due to presence of nanoparticles thermal conductivity of the nanowire was observed to decrease and up to 40% reduction in thermal conductivity was observed. With the increase in number of the nanoparticles, thermal conductivity was observed to decrease; however size of nanoparticles has little effect.

  2. Conductivity study and fourier transform infrared (FTIR) characterization of methyl cellulose solid polymer electrolyte with sodium iodide conducting ion

    SciTech Connect

    Abiddin, Jamal Farghali Bin Zainal; Ahmad, Azizah Hanom

    2015-08-28

    Sodium ion (Na{sup +}) based solid polymer electrolyte (SPE) has been prepared using solution cast technique with distilled water as solvent and Methylcellulose (MC) as a polymer host. Methylcellulose polymer was chosen as the polymer host due to the abundance of lone pair electrons in the carbonyl and C-O-C constituents, which in turn provide multiple hopping sites for the Na{sup +} conducting ions. Variable compositions of sodium iodide (NaI) salt were prepared to investigate the optimum MC-NaI weight ratio. Results from Electrical Impedance Spectroscopy (EIS) technique show that pure methylcellulose has a low conductivity of 3.61 × 10{sup −11} S/cm.The conductivity increases as NaI content increases up to optimum NaIcomposition of 40 wt%, which yields an average conductivity of 2.70 × 10{sup −5} S/cm.

  3. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: SOLVENT EXTRACTION QUICK REFERENCE FACT SHEET

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of remedy evaluation and selection under the Superfund Program. his fact sheet focuses on solvent extraction treatability studies, and is highly abridged version of the guide which bears the...

  4. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: THERMAL DESORPTION - INTERIM GUIDANCE

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (RI/FS) process and the remedial design remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation, and Liab...

  5. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: AEROBIC BIODEGRADATION REMEDY SCREENING

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (KU FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation, and L...

  6. Efficacy and safety of dutasteride, tamsulosin and their combination in a subpopulation of the CombAT study: 2-year results in Asian men with moderate-to-severe BPH.

    PubMed

    Chung, B-H; Roehrborn, C G; Siami, P; Major-Walker, K; Morrill, B B; Wilson, T H; Montorsi, F

    2009-01-01

    Although ethnicity-based differences in prostate size and physiology have been reported, results of benign prostatic hyperplasia (BPH) treatment trials in predominantly Caucasian patients are assumed to be applicable to non-Caucasian populations. This post hoc analysis investigated whether an Asian subpopulation of men with moderate-to-severe BPH in the CombAT study achieves treatment responses in line with those of the overall study population. In this double-blind, randomized, parallel-group trial, 325 Asian men were assigned to treatment with 0.5 mg dutasteride once daily, 0.4 mg tamsulosin once daily or the combination. Decrease in international prostate symptom score (IPSS) at month 24 from baseline (the primary endpoint) was significantly greater with combination treatment compared with tamsulosin (P<0.05), and numerically, but not statistically significantly, greater compared with dutasteride. Mean IPSS was reduced from baseline by 7.5 (+/-0.84) in the combination group, by 6.3 (+/-0.86) in the dutasteride group and by 4.5 (+/-0.78) in the tamsulosin group, resulting in respective mean IPSS at months 24 of 11.4 (+/-0.60), 12.7 (+/-0.70) and 14.3 (+/-0.74). The adverse event profile was similar to that observed in the overall CombAT population, and drug-related adverse events were more common with combination therapy (26%) than with tamsulosin (15%) or dutasteride (9%). No unexpected adverse events emerged. In conclusion, in Asian men with moderate-to-severe lower urinary tract symptoms and an enlarged prostate, combination therapy achieved significantly greater improvements from baseline BPH symptoms, flow rate, quality of life, reduced prostate volume and improved treatment satisfaction compared with tamsulosin monotherapy. PMID:18813219

  7. Immunogenicity, Safety, and Tolerability of 13-Valent Pneumococcal Conjugate Vaccine Followed by 23-Valent Pneumococcal Polysaccharide Vaccine in Recipients of Allogeneic Hematopoietic Stem Cell Transplant Aged ≥2 Years: An Open-Label Study

    PubMed Central

    Cordonnier, Catherine; Ljungman, Per; Juergens, Christine; Maertens, Johan; Selleslag, Dominik; Sundaraiyer, Vani; Giardina, Peter C.; Clarke, Keri; Gruber, William C.; Scott, Daniel A.; Schmoele-Thoma, Beate

    2015-01-01

    Background. Life-threatening Streptococcus pneumoniae infections often occur after hematopoietic stem cell transplant (HSCT); vaccination is important for prevention. Methods. In an open-label study, patients (n = 251) 3–6 months after allogeneic HSCT received 3 doses of 13-valent pneumococcal conjugate vaccine (PCV13) at 1-month intervals, a fourth dose 6 months later, and 1 dose of 23-valent pneumococcal polysaccharide vaccine (PPSV23) 1 month later. Immunogenicity at prespecified time points and vaccine safety were assessed. Results. In the evaluable immunogenicity population (N = 216; mean age, 37.8 years), geometric mean fold rises (GMFRs) of immunoglobulin G geometric mean concentrations from baseline to postdose 3 showed significant increases in antibody levels across all PCV13 serotypes (GMFR range, 2.99–23.85; 95% confidence interval lower limit, >1); there were significant declines over the next 6 months, significant increases from predose 4 to postdose 4 (GMFR range, 3.00–6.97), and little change after PPSV23 (GMFR range, 0.86–1.12). Local and systemic reactions were more frequent after dose 4. Six patients experienced serious adverse events possibly related to PCV13 (facial diplegia, injection-site erythema and pyrexia, autoimmune hemolytic anemia, and suspected lack of vaccine efficacy after dose 3 leading to pneumococcal infection), PCV13 and PPSV23 (Guillain-Barré syndrome), or PPSV23 (cellulitis). There were 14 deaths, none related to study vaccines. Conclusions. A 3-dose PCV13 regimen followed by a booster dose may be required to protect against pneumococcal disease in HSCT recipients. Dose 4 was associated with increased local and systemic reactions, but the overall safety profile of a 4-dose regimen was considered acceptable. Clinical Trials Registration. NCT00980655. PMID:25870329

  8. Construction work practices and conditions improved after 2-years' participation in the HomeSafe pilot program.

    PubMed

    Gilkey, David P; Hautaluoma, Jacob E; Ahmed, Taslim P; Keefe, Thomas J; Herron, Robert E; Bigelow, Philip L

    2003-01-01

    This study reevaluated changes in job-site safety audit scores for a cohort of residential construction workers that had protracted exposure to the HomeSafe pilot program for 2(1/2) years. The investigation was a repeated measure of a cohort study underway in the six-county metro area of Denver, Colo. The larger study was a longitudinal, quasi-experimental design with a cohort of residential construction workers within the HomeSafe strategic partnership between Occupational Safety and Health Administration Region VIII and the Home Builders Association of Metropolitan Denver (HBA). Audits were conducted on residential construction sites. Study subjects were construction workers employed by partner or control companies within the study. Repeated measures of 41 companies showed significant improvement (p=.01) in audit scores, increasing from 71.8 to 76.8 after 2(1/2) years in the program. HomeSafe companies out-performed controls (p=.01) for both the retest group and previously unaudited HomeSafe companies. Prolonged exposure in the HomeSafe pilot program resulted in improved audit scores for companies within the program for at least 2 years. PMID:12809540

  9. 21 CFR 312.120 - Foreign clinical studies not conducted under an IND.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... measures described in the study protocol or elsewhere will protect the rights, safety, and well-being of...) monitored the study and ensured that the study was carried out consistently with the study protocol; and (11...)(i) of this section) and to conduct the study in accordance with the study protocol, and a...

  10. Note: Optimization of the numerical data analysis for conductivity percolation studies of drying moist porous systems

    SciTech Connect

    Moscicki, J. K.; Sokolowska, D.; Dziob, D.; Nowak, J.; Kwiatkowski, L.

    2014-02-15

    A simplified data analysis protocol, for dielectric spectroscopy use to study conductivity percolation in dehydrating granular media is discussed. To enhance visibility of the protonic conductivity contribution to the dielectric loss spectrum, detrimental effects of either low-frequency dielectric relaxation or electrode polarization are removed. Use of the directly measurable monofrequency dielectric loss factor rather than estimated DC conductivity to parameterize the percolation transition substantially reduces the analysis work and time.

  11. Conducting Real-Time Videofluoroscopic Swallow Study via Telepractice: A Preliminary Feasibility and Reliability Study.

    PubMed

    Burns, Clare L; Ward, Elizabeth C; Hill, Anne J; Phillips, Nick; Porter, Linda

    2016-06-01

    A small number of studies have examined the feasibility of conducting videofluoroscopic swallow studies (VFSS) via telepractice. While the results have confirmed this potential, the systems tested to date have either reported issues that impacted the ability to analyze/interpret the VFSS recordings in real time, or they were not designed to enable real-time interpretation. Further system design is needed to establish a telepractice model that enables the VFSS assessment to be both guided and interpreted live in real time. The aim of this study was to test the feasibility and reliability of using a telepractice system to enable live VFSS assessment. Twenty adult patients underwent a VFSS assessment directed by a telepractice SLP with competency in VFSS located in another room of the hospital. The telepractice clinician led the sessions using a C20 Cisco TelePresence System. This was linked in real time via a secure telehealth network (at 4 megabits per second (Mbit/s)) to a C60 Cisco TelePresence System located in a fluoroscopy suite, connected to the digital fluoroscopy system. Levels of agreement were calculated between the telepractice clinician and a face-to-face clinician who simultaneously rated the VFSS in real time. High levels of agreement for swallowing parameters (range = 75-100 %; k = -0.34 to 1.0) and management decisions (range = 70-100 %, k = 0.64-1.0) were found. A post-session questionnaire revealed clinicians agreed that the telepractice system enabled successful remote assessment of VFSS. The findings support the potential to conduct live VFSS assessment via a telepractice model. PMID:26979971

  12. Human subject protection; foreign clinical studies not conducted under an investigational new drug application. Final rule.

    PubMed

    2008-04-28

    The Food and Drug Administration (FDA) is amending its regulations on acceptance of foreign clinical studies not conducted under an investigational new drug application (IND) (non-IND foreign clinical studies) as support for an IND or application for marketing approval for a drug or biological product. The final rule replaces the requirement that these studies be conducted in accordance with ethical principles stated in the Declaration of Helsinki (Declaration) issued by the World Medical Association (WMA), specifically the 1989 version (1989 Declaration), with a requirement that the studies be conducted in accordance with good clinical practice (GCP), including review and approval by an independent ethics committee (IEC). The final rule updates the standards for the acceptance of foreign clinical studies not conducted under an IND and helps ensure the protection of human subjects and the quality and integrity of data obtained from these studies. PMID:18567164

  13. Conductivity of nanosecond discharges in nitrogen and sulfur hexafluoride studied by particle-in-cell simulations

    SciTech Connect

    Levko, D.; Gurovich, V. Tz.; Krasik, Ya. E.

    2012-06-15

    The conductivity of the discharge gap during the nanosecond high-voltage pulsed discharge in nitrogen and sulfur hexafluoride is studied using particle-in-cell numerical simulations. It is shown that the conductivity in different locations of the cathode-anode gap is not uniform and that the conductivity is determined by both the runaway and the plasma electrons. In addition, it is shown that runaway electrons generated prior to the virtual cathode formation pre-ionize the discharge gap, which makes it conductive.

  14. Simulation study on effects of channel noise on differential conduction at an axon branch.

    PubMed Central

    Horikawa, Y

    1993-01-01

    Effects of membrane channel noise (random opening and closing of ion channels) are studied on spike conduction at a branching point on an axon. Computer simulation is done on the basis of a stochastic version of the Hodgkin-Huxley cable model, into which the channel noise is incorporated. It is shown that the channel noise makes conduction of spikes into daughter branches random; spikes randomly succeed or fail in conduction into daughter branches. The conduction is then randomly differential even though the forms and properties of daughter branches are the same. The randomness is considerable when the radius of an axon is small (approximately 1 microns). PMID:7693002

  15. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false How can I request assistance to conduct a feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Overview § 404.18 How can I request assistance to conduct...

  16. First-Year Students' Expectations of Conduct and Consequence: A Case Study

    ERIC Educational Resources Information Center

    Crance Gutmann, Gina-Lyn

    2008-01-01

    Research on first-year students' expectations about college has explored areas of academic and social expectations, but not first-year college students' expectations about judicial conduct and consequence. The purpose of this study was to empirically explore two questions: what are first year students' expectations about campus conduct and…

  17. 43 CFR 404.18 - How can I request assistance to conduct a feasibility study?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false How can I request assistance to conduct a feasibility study? 404.18 Section 404.18 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Overview § 404.18 How can I request assistance to conduct...

  18. Infrared spectroscopic and conductivity studies of ureasil-based proton conducting membranes for medium temperature fuel cell applications.

    PubMed

    Vince, Jelica; Vuk, Angela Šurca; Stangar, Urška Lavrenčič; Perše, Lidija Slemenik; Orel, Boris; Hočevar, Stanko

    2010-12-01

    Proton conducting membranes for fuel cells were prepared by the sol-gel process from two different ureasil organic-inorganic hybrid precursors: bis[(N-(3-triethoxysilylpropyl)ureido]-terminated poly(propylene glycol) 4000 (PPGU) and bis[3-(N-(3-triethoxysilylpropyl)ureido)propyl]-terminated poly(dimethylsiloxane) 1000 (PDMSU). Heteropoly silicotungstic acid was added to actuate the reactions of hydrolysis and condensation and to introduce proton conductivity. XRD measurements of membranes revealed the presence of a diffraction peak at 6.3°, which could be ascribed to gradual formation of R-(SiO3/2) silsesquioxane clusters, i.e. arrangement of the Si-O-Si skeleton on the nano-scale. TG and DSC measurements showed thermal stability of the membranes above 120 °C. Proton conductivities at room temperature were of the order of 10-4 to 10-3 S/cm, classifying the membranes in the group of super ionic conductors. At elevated temperatures up to 160 °C and at conditions of autogenous pressure, conductivities increased up to values acceptable for fuel cells of 10-1 S/cm, which could be the result of the presence of H3O+ ions. The protonation of the urea groups and the formation of amidonium ions [C(OH)=NH+] were followed using IR ATR spectroscopy. PMID:24061888

  19. "Conducting Is Everywhere!" A Case Study of the Development of Preservice Music Teacher Occupational Identity in a Beginning Conducting Course

    ERIC Educational Resources Information Center

    Johnson, Erik

    2014-01-01

    Research on pre-service music teacher occupational identity often highlights two competing identities: performer and teacher (L'Roy, 1983; Roberts, 1991; Pellegrino, 2009). Of the many factors that contribute to the occupational identity of the pre-service music teacher (Woodford, 2002), conducting has the potential to integrate performer and…

  20. Latino Community-Based Participatory Research Studies: A Model for Conducting Bilingual Translations

    PubMed Central

    Sánchez-Johnsen, Lisa; Escamilla, Julia; Rodriguez, Erin M.; Vega, Susan; Bolaños, Liliana

    2015-01-01

    Many behavioral health materials have not been translated into Spanish. Of those that are available in Spanish, some of them have not been translated correctly, many are only appropriate for a subgroup of Latinos, and/or multiple versions of the same materials exist. This article describes an innovative model of conducting bilingual English–Spanish translations as part of community-based participatory research studies and provides recommendations based on this model. In this article, the traditional process of conducting bilingual translations is reviewed, and an innovative model for conducting translations in collaboration with community partners is described. Finally, recommendations for conducting future health research studies with community partners are provided. Researchers, health care providers, educators, and community partners will benefit from learning about this innovative model that helps produce materials that are more culturally appropriate than those that are produced with the most commonly used method of conducting translations. PMID:25741929

  1. Patterns of fatigue and its correlates over the first 2 years after traumatic brain injury.

    PubMed

    Bushnik, Tamara; Englander, Jeffrey; Wright, Jerry

    2008-01-01

    This study used a prospective longitudinal design to quantify fatigue and associated factors during the first 2 years after traumatic brain injury (TBI). Fifty-one individuals were assessed at 3 time points: within the first 6, 12, and 18-24 months after TBI. Self-reported fatigue improved during the first year, as did pain, sleep quality, cognitive independence, and involvement in productive activity. Further changes up to 2 years after TBI were not observed. The subset of individuals who reported significant increases in fatigue over the first 2 years demonstrated poorer outcomes in cognition, motor symptoms, and general functioning than those with decreased or stable fatigue. PMID:18219232

  2. Thermal design studies in superconducting rf cavities: Phonon peak and Kapitza conductance

    NASA Astrophysics Data System (ADS)

    Aizaz, A.; Grimm, T. L.; Wright, N. T.

    2010-09-01

    Thermal design studies of superconducting radio frequency (SRF) cavities involve two thermal parameters, namely the temperature dependent thermal conductivity of Nb at low temperatures and the heat transfer coefficient at the Nb-He II interface, commonly known as the Kapitza conductance. During the fabrication process of the SRF cavities, Nb sheet is plastically deformed through a deep drawing process to obtain the desired shape. The effect of plastic deformation on low temperature thermal conductivity as well as Kapitza conductance has been studied experimentally. Strain induced during the plastic deformation process reduces the thermal conductivity in its phonon transmission regime (disappearance of phonon peak) by 80%, which may explain the performance limitations of the defect-free SRF cavities during their high field operations. Low temperature annealing of the deformed Nb sample could not recover the phonon peak. However, moderate temperature annealing during the titanification process recovered the phonon peak in the thermal conductivity curve. Kapitza conductance measurements for the Nb-He II interface for various surface topologies have also been carried out before and after the annealing. These measurements reveal consistently increased Kapitza conductance after the annealing process was carried out in the two temperature regimes.

  3. Evaluation of Nerve Conduction Studies in Obese Children With Insulin Resistance or Impaired Glucose Tolerance.

    PubMed

    Ince, Hülya; Taşdemir, Haydar Ali; Aydin, Murat; Ozyürek, Hamit; Tilki, Hacer Erdem

    2015-07-01

    The aim of the study was to investigate nerve conduction studies in terms of neuropathic characteristics in obese patients who were in prediabetes stage and also to determine the abnormal findings. The study included 69 obese adolescent patients between April 2009 and December 2010. All patients and control group underwent motor (median, ulnar, tibial, and peroneal) and sensory (median, ulnar, sural, and medial plantar) nerve conduction studies and sympathetic skin response test. Sensory response amplitude of the medial plantar nerve was significantly lower in the patients with impaired glucose tolerance and insulin resistance. To our knowledge, the present study is the first study demonstrating the development of sensory and autonomic neuropathy due to metabolic complications of obesity in adolescent children even in the period without development of diabetes mellitus. We recommend that routine electrophysiological examinations be performed, using medial plantar nerve conduction studies and sympathetic skin response test. PMID:25342307

  4. Clinical Features and Treatment Outcomes of Primary Immune Thrombocytopenic Purpura in Hospitalized Children Under 2-Years Old

    PubMed Central

    Farhangi, H; Ghasemi, A; Banihashem, A; Badiei, Z; Jarahi, L; Eslami, G; Langaee, T

    2016-01-01

    Background Immune thrombocytopenic purpura (ITP) is the most prevalent cause of thrombocytopenia in children. Despite the importance of ITP in children under 2-years old, only a few publications are available in the literature.ITP usually presents itself as isolated thrombocytopenia and mucocutaneous bleeding. Materials and Methods This study was conducted on 187 under 2-year-old children diagnosed with ITP and treated at Dr. Sheikh Hospital from 2004 to 2011.In this retrospective study, clinical symptoms, laboratory findings, history of viral infections, vaccination history, and treatment efficacy in children under 2-years old with ITP were investigated.Patients were followed for one year after being discharged from the hospital. Results The risk of the disease developing into chronic form was higher in older children (0.001). ITP in children under 3-months old was significantly associated with vaccination (p=0.007). There was no significant differences between male and female patients in regards to newly diagnosed ITP, persistent, and chronic disease status (p = 0.21). No significant difference in bleeding symptoms was observed between patients under 3-months old and 3 to 24-months old (p=0.18). Conclusion Infantile ITP respond favorably to treatment. The risk of the disease developing into chronic form is higher in 3-to-24-month-old children compared to under-three-month olds. PMID:27222699

  5. Developmental Associations Between Conduct Problems and Expressive Language in Early Childhood: A Population-Based Study.

    PubMed

    Girard, Lisa-Christine; Pingault, Jean-Baptiste; Doyle, Orla; Falissard, Bruno; Tremblay, Richard E

    2016-08-01

    Conduct problems have been associated with poor language development, however the direction of this association in early childhood remains unclear. This study examined the longitudinal directional associations between conduct problems and expressive language ability. Children enrolled in the UK Millennium Cohort Study (N = 14, 004; 50.3 % boys) were assessed at 3 and 5 years of age. Parent reports of conduct problems and standardised assessments of expressive language were analyzed using cross-lagged modeling. Conduct problems at 3 years was associated with poorer expressive language at 5 years and poorer expressive language at 3 years was associated with increased conduct problems by 5 years. The results support reciprocal associations, rather than a specific unidirectional path, which is commonly found with samples of older children. The emergence of problems in either domain can thus negatively impact upon the other over time, albeit the effects were modest. Studies examining the effects of intervention targeting conduct problems and language acquisition prior to school entry may be warranted in testing the efficacy of prevention programmes related to conduct problems and poor language ability early in childhood. PMID:26496905

  6. Conducting feasibilities in clinical trials: an investment to ensure a good study.

    PubMed

    Rajadhyaksha, Viraj

    2010-07-01

    Conducting clinical trial feasibility is one of the first steps in clinical trial conduct. This process includes assessing internal and environmental capacity, alignment of the clinical trial in terms of study design, dose of investigational product, comparator, patient type, with the local environment and assessing potential of conducting clinical trial in a specific country. A robust feasibility also ensures a realistic assessment and capability to conduct the clinical trial. For local affiliates of pharmaceutical organizations, and contract research organizations, this is a precursor to study placement and influences the decision of study placement. This article provides details on different types of feasibilities, information which is to be included and relevance of each. The article also aims to provide practical hands-on suggestions to make feasibilities more realistic and informative. PMID:21814631

  7. First-principles study of lattice thermal conductivity of Td-WTe2

    NASA Astrophysics Data System (ADS)

    Liu, Gang; Sun, Hong Yi; Zhou, Jian; Li, Qing Fang; Wan, Xian-Gang

    2016-03-01

    The structural and thermal properties of bulk Td-WTe2 have been studied by using first-principles calculations based on the simple Klemens model and an iterative self-consistent method. Both methods show that lattice thermal conductivity is anisotropic, with the highest value in the (001) plane, and lowest one along the c-axis at 300 K. The calculated average thermal conductivity of WTe2 is in agreement with the experimental measurement. The size dependent thermal conductivity shows that nanostructuring of WTe2 can possibly further decrease the lattice thermal conductivity, which can improve the thermoelectric efficiency. Such extremely low thermal conductivity, even much lower than WSe2, makes WTe2 having many potential applications in thermal insulation and thermoelectric materials.

  8. Communication: Minimum in the thermal conductivity of supercooled water: A computer simulation study

    SciTech Connect

    Bresme, F.; Biddle, J. W.; Sengers, J. V.; Anisimov, M. A.

    2014-04-28

    We report the results of a computer simulation study of the thermodynamic properties and the thermal conductivity of supercooled water as a function of pressure and temperature using the TIP4P-2005 water model. The thermodynamic properties can be represented by a two-structure equation of state consistent with the presence of a liquid-liquid critical point in the supercooled region. Our simulations confirm the presence of a minimum in the thermal conductivity, not only at atmospheric pressure, as previously found for the TIP5P water model, but also at elevated pressures. This anomalous behavior of the thermal conductivity of supercooled water appears to be related to the maximum of the isothermal compressibility or the minimum of the speed of sound. However, the magnitudes of the simulated thermal conductivities are sensitive to the water model adopted and appear to be significantly larger than the experimental thermal conductivities of real water at low temperatures.

  9. Cost and Schedule Analytical Techniques Development: Option 2 Year

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This Final Report summarizes the activities performed by Science Applications International Corporation (SAIC) for the Option 2 Year from December 1, 1996 through November 30, 1997. The Final Report is in compliance with Paragraph 5 of Section F of the contract. This CSATD contract provides products and deliverable in the form of models, data bases, methodologies, studies and analyses for the NASA Marshall Space Flight Center's (MSFC) Engineering Cost Office (PPO3) the Program Plans and Requirements Officer (PP02), and other user organizations. Detailed Monthly Progress reports were submitted to MSFC in accordance with the contract's Statement of Work, Section TV "Reporting and Documentation". These reports spelled out each month's specific work accomplishments, deliverables submitted, major meetings held, and other pertinent information. This Final Report will summarize these activities at higher level. During this contract Option Year, SAIC expended 29,830 man-hours in tile performance of tasks called out in the Statement of Work and reported oil in this yearly Final Report. This represents approximately 16 full-time EPs. Included are the basis Huntsville-based team, plus SAIC specialists in San Diego, Ames Research Center, Chicago, and Colorado Springs performing specific tasks for which they are uniquely qualified.

  10. The Relationship between Nerve Conduction Study and Clinical Grading of Carpal Tunnel Syndrome

    PubMed Central

    Cheluvaiah, Janardhan D.; Agadi, Jagadish B.; Nagaraj, Karthik

    2016-01-01

    Introduction Carpal Tunnel Syndrome (CTS) is the most common nerve entrapment. Subjective sensory symptoms are common place in patients with CTS, but sometimes they are not supported by objective findings in the neurological examination. Electrodiagnostic (EDx) studies are a valid and reliable means of confirming the diagnosis. The amplitudes along with the conduction velocities of the sensory nerve action potential and motor nerve action potential reflect the functional state of axons, and are useful parameters and complement the clinical grading in the assessment of severity of CTS. Aim To conduct median nerve sensory and motor conduction studies on patients with carpal tunnel syndrome and correlate the relationship between nerve conduction study parameters and the clinical severity grading. Materials and Methods Based on clinical assessment, the study patients were divided into 03 groups with mild CTS, moderate CTS and severe CTS respectively as per Mackinnson’s classification. Median and ulnar nerve conduction studies were performed on bilateral upper limbs of 50 patients with symptoms of CTS and 50 age and sex matched healthy control subjects. The relationship between the clinical severity grade and various nerve conduction study parameters were correlated. Results In this prospective case control study, 50 patients with symptoms consistent with CTS and 50 age and sex matched healthy control subjects were examined over a 10 month period. A total of 30 patients had unilateral CTS (right upper limb in 19 and left upper limb in 11) and 20 patients had bilateral CTS. Female to male ratio was 3.54 to 1. Age ranged from 25 to 81 years. The mean age at presentation was 49.68±11.7 years. Tingling paresthesias of hand and first three fingers were the most frequent symptoms 48 (98%). Tinel’s and Phalen’s sign were positive in 36 (72%) and 44 (88%) patients respectively. The mean duration of symptoms at presentation was 52.68±99.81 weeks. 16 patients (32%) had

  11. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 33 2012-07-01 2012-07-01 false Submission of study plans and conduct... RULES Implementation, Enforcement and Modification of Consent Agreements § 790.62 Submission of study... pursuant to a consent agreement shall submit a study plan no later than 45 days prior to the initiation...

  12. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 32 2014-07-01 2014-07-01 false Submission of study plans and conduct... RULES Implementation, Enforcement and Modification of Consent Agreements § 790.62 Submission of study... pursuant to a consent agreement shall submit a study plan no later than 45 days prior to the initiation...

  13. Treatment Integrity: A Review of Intervention Studies Conducted with Children with Autism

    ERIC Educational Resources Information Center

    Wheeler, John J.; Baggett, Bob A.; Fox, James; Blevins, Leia

    2006-01-01

    The purpose of this study was to assess the degree to which behavioral intervention studies conducted with children diagnosed with autism operationally defined the independent variables (IVs) and evaluated treatment integrity (TI). The study replicated the criteria from Gresham, Gansle, and Noell (1993) and focused exclusively on research studies…

  14. An Assessment of Treatment Integrity in Behavioral Intervention Studies Conducted with Persons with Mental Retardation

    ERIC Educational Resources Information Center

    Wheeler, John J.; Mayton, Michael R.; Carter, Stacy L.; Chitiyo, Morgan; Menendez, Anthony L.; Huang, Ann

    2009-01-01

    The purpose of this study was to assess the degree to which behavioral intervention studies conducted with persons with mental retardation operationally defined the independent variables and evaluated and reported measures of treatment integrity. The study expands the previous work in this area reported by Gresham, Gansle, and Noell (1993) and…

  15. Nanoscale electrical property studies of individual GeSi quantum rings by conductive scanning probe microscopy

    PubMed Central

    2012-01-01

    The nanoscale electrical properties of individual self-assembled GeSi quantum rings (QRs) were studied by scanning probe microscopy-based techniques. The surface potential distributions of individual GeSi QRs are obtained by scanning Kelvin microscopy (SKM). Ring-shaped work function distributions are observed, presenting that the QRs' rim has a larger work function than the QRs' central hole. By combining the SKM results with those obtained by conductive atomic force microscopy and scanning capacitance microscopy, the correlations between the surface potential, conductance, and carrier density distributions are revealed, and a possible interpretation for the QRs' conductance distributions is suggested. PMID:23194252

  16. Feasible Study for Multi-photon Stereolithography Method of Electro Conductive Polymer Actuator with Complex Shape

    NASA Astrophysics Data System (ADS)

    Sone, Junji; Asami, Akihisa; Yamada, Katsumi; Chen, Jun

    Recently, a soft actuator was developed using an electro-conducting polymer and an ionic conducting polymer. Moreover, stereolithography that uses a femtosecond laser was researched as a method of multiphoton-sensitized polymerization. In this study, we tried a more stable and more rapid stereolithography method for fabricating an electro-conducting polymer using a protein material. From the results of this study, we found that the method was 10 times faster when an aqueous solid that included an electro-conducting polymer, a catalyst, and gelatine was used. In addition, it was stable in that the temperature of the aqueous solid was controlled at 10 degree. We built a 3D shape using the newly developed method, and we will apply this method to a complex actuator.

  17. [Surgical closure of interventricular communications before 2 years of age. Long-term clinical and electrocardiographic course].

    PubMed

    Barrey, C; Petit, J; Losay, J; Lucet, P; Bruniaux, J; Langlois, J; Planche, C; Binet, J P

    1985-11-01

    The long-term follow-up of the first 100 children under 2 years of age, presenting with ventricular septal defect (VSD) who underwent surgical closure between 1972 and 1976 at the Centre Chirurgical Marie-Lannelongue, was studied. Only cases with isolated VSD were taken into account except for 18 cases with ductus arteriosus related to operation and 41 cases with atrial septal defect (ASD) or persistent foramen ovale. This study included clinical and electrocardiographic investigations focused on the long-term follow-up of conduction disorders. Clinical tolerance was excellent with only one Eisenmenger's syndrome induced by a residual VSD. Three secondary cases of aortic regurgitation without present functional repercussions were observed. Conduction disorders were considered as unchanged or even improved. There were no sudden death, no secondary atrioventricular block (AVB), no trifascicular block even after one case with transitory immediate postoperative AVB. PMID:4083976

  18. AC conductivity and Dielectric Study of Chalcogenide Glasses of Se-Te-Ge System

    NASA Astrophysics Data System (ADS)

    Salman, Fathy

    2004-01-01

    The ac conductivity and dielectric properties of glassy system SexTe79 - xGe21, with x = 11, 14, 17 at.%, has been studied at temperatures 300 to 450 K and over a wide range of frequencies (50 Hz to 500 kHz). Experimental results indicate that the ac conductivity and the dielectric constants depend on temperature, frequency and Se content. The conductivity as a function of frequency exhibited two components: dc conductivity s dc, and ac conductivity s ac, where s ac ˜ w s. The mechanism of ac conductivity can be reasonably interpreted in terms of the correlated barrier hopping model (CBH). The activation energies are estimated and discussed. The dependence of ac conductivity and dielectric constants on the Se content x can be interpreted as the effect of Se fraction on the positional disorder. The impedance plot at each temperature appeared as a semicircle passes through the origin. Each semicircle is represented by an equivalent circuit of parallel resistance Rb and capacitance Cb.

  19. Conducting ecologically valid prevention research: recruiting and retaining a "whole village" in multimethod, multiagent studies.

    PubMed

    Capaldi, D M; Chamberlain, P; Fetrow, R A; Wilson, J E

    1997-08-01

    Many prevention studies are now designed with complementary interventions in different settings. Evaluations of these interventions require assessing the child's behavior in each of these settings. Conducting these studies, therefore, may involve recruiting school districts, principals, classroom teachers, peers, parents, siblings, and in later years, employers and intimate partners. These participants may be considered natural raters or satellite subjects, depending on their degree of involvement. Issues of recruitment and retention thus are magnified in multimethod, multiagent studies. To illustrate these issues, findings are presented for three studies conducted with risk populations in the past decade at the Oregon Social Learning Center: a passive longitudinal study, a selected prevention study, and an indicated prevention study. Findings indicate that achieving high recruitment and retention rates for at-risk and high-risk subjects in multisetting studies is possible, and that a developmental approach should be taken to recruiting risk populations. PMID:9338955

  20. 42 CFR 90.8 - Conduct of health assessments and health effects studies.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Conduct of health assessments and health effects studies. 90.8 Section 90.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND...

  1. 43 CFR 404.47 - How will a feasibility study be conducted under this program?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false How will a feasibility study be conducted under this program? 404.47 Section 404.47 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Feasibility Studies § 404.47 How will a feasibility...

  2. 76 FR 75875 - Plan for Conduct of 2012 Electric Transmission Congestion Study

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-05

    ... regional workshops and request for written comments in connection with the preparation of a study of electric transmission congestion pursuant to section 216(a)(1) of the Federal Power Act (76 FR 70122). This... for Conduct of 2012 Electric Transmission Congestion Study AGENCY: Office of Electricity Delivery...

  3. 42 CFR 90.8 - Conduct of health assessments and health effects studies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Conduct of health assessments and health effects studies. 90.8 Section 90.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND...

  4. Characterizing Measurement Error in Test Scores across Studies: A Tutorial on Conducting "Reliability Generalization" Analyses.

    ERIC Educational Resources Information Center

    Henson, Robin K.; Thompson, Bruce

    Given the potential value of reliability generalization (RG) studies in the development of cumulative psychometric knowledge, the purpose of this paper is to provide a tutorial on how to conduct such studies and to serve as a guide for researchers wishing to use this methodology. After some brief comments on classical test theory, the paper…

  5. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: SOLVENT EXTRACTION - INTERIM GUIDANCE

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (RI/FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation and Liabi...

  6. GUIDE TO CONDUCTING TREATABILITY STUDIES UNDER CERCLA: SOIL WASHING - INTERIM GUIDANCE

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of the remedial investigation/feasibility study (RI/FS) process and the remedial design/remedial action (RD/RA) process under the Comprehensive Environmental Response, Compensation, and Liab...

  7. Methodological, Theoretical, Infrastructural, and Design Issues in Conducting Good Outcome Studies

    ERIC Educational Resources Information Center

    Kelly, Michael P.; Moore, Tessa A.

    2011-01-01

    This article outlines a set of methodological, theoretical, and other issues relating to the conduct of good outcome studies. The article begins by considering the contribution of evidence-based medicine to the methodology of outcome research. The lessons which can be applied in outcome studies in nonmedical settings are described. The article…

  8. Study of the Kinetics of an S[subscript N]1 Reaction by Conductivity Measurement

    ERIC Educational Resources Information Center

    Marzluff, Elaine M.; Crawford, Mary A.; Reynolds, Helen

    2011-01-01

    Substitution reactions, a central part of organic chemistry, provide a model system in physical chemistry to study reaction rates and mechanisms. Here, the use of inexpensive and readily available commercial conductivity probes coupled with computer data acquisition for the study of the temperature and solvent dependence of the solvolysis of…

  9. ORGANOTIN TOXICITY STUDIES CONDUCTED WITH SELECTED MARINE ORGANISMS AT EPA'S ENVIRONMENTAL RESEARCH LABORATORY, GULF BREEZE, FLORIDA

    EPA Science Inventory

    Studies on effect of bis(tri-n-butyltin)oxide (TBTO) and other organotins on marine species have been conducted at the U.S. Environmental Protection Agency's laboratory at Gulf Breeze, Florida, since 1983. First studies were done on two species of algae, Skeletonema costatum and ...

  10. A numerical study of the influence of interconnected conductive paths in electrically resistive rocks

    NASA Astrophysics Data System (ADS)

    Mandolesi, E.; Moorkamp, M.; Jones, A. G.

    2013-12-01

    Several electromagnetic (EM) geophysical methods focus on the EM properties of rocks and sediments to determine a reliable image of the subsurface, while the same electromagnetic properties are measured in the laboratory with a wide range of instruments and techniques. None of these measurements return an unequivocal result. The hypothesis related to the presence of interconnected pathways of electrically conductive materials in resistive hosts has been studied with increasing interest in recent years, and the comprehension of phenomena that scale from the microstructures of the rocks up to field electrical conductivity measurements represents the boundary that prevents the direct comparison between laboratory data and field data. In recent years some numerical approaches have been investigated to understand the effects of interconnected pathways of conductors on field measurements, usually restricting the studies to direct current (DC) sources. Bearing in mind the time-variating nature of natural electromagnetic sources that take a role in field measurements, we numerically simulated the effects of such EM sources on the conductivity measured on the surface of a three-dimensional realistic body embedded in an uniform host by using electromagnetic induction equations. Since most real rocks are poor conductors, we modeled a two-phase mixture of rock and interconnected conductive elements (representing melts, saline fluids, sulphidic, carbonitic, or metallic sediments, etc.), randomly generated within the background host. We compared the electrical conductivity measured from a sample of randomly generated models with the electrical conductivity limits predicted by Hashin-Shtrikman bounds.

  11. The conductive properties of single DNA molecules studied by torsion tunneling atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Wang, W.; Niu, D. X.; Jiang, C. R.; Yang, X. J.

    2014-01-01

    The conductive properties of single natural λ-DNA molecules are studied by torsion tunneling atomic force microscopy (TR-TUNA). The currents both parallel to and perpendicular to the DNA chains are investigated, but only weak or even no current signals are detected by TR-TUNA. To improve the conductance of DNA molecules, silver and copper metallized DNAs are fabricated and their conductivities are checked by TR-TUNA. It is found that for both Cu- and Ag-DNAs, the conductivity perpendicular to the DNA chain is enhanced significantly as the metal clusters are attached to the DNA chains. But parallel to the chain the electrical transport is still weak, most probably due to the ‘beads-on-a-string’ constructions of metallized DNAs.

  12. AC Conductivity Studies in Lithium-Borate Glass Containing Gold Nanoparticles

    NASA Astrophysics Data System (ADS)

    Shivaprakash, Y.; Anavekar, R. V.

    2011-07-01

    Gold nanoparticles have been synthesized in a base glass with composition 30Li2O-70B2O3 using gold chloride (HAuCl4.3H2O) as a dopant. The samples are characterized using XRD, ESR, SEM and optical absorption in the visible range. AC conductivity studies have been performed at RT over a frequency range 100 to 10 MHz. The dc conductivity is calculated from the complex impedence plot. The dc conductivity is found to be increasing with the increase of dopant concentration. AC conductivity data is fitted with Almond-West law with power exponent `s'. The values of `s' is found to lie in the range of 0.70-0.73.

  13. Conductance of ferro- and antiferro-magnetic single-atom contacts: A first-principles study

    SciTech Connect

    Tan, Zhi-Yun; Zheng, Xiao-long; Ye, Xiang; Xie, Yi-qun; Ke, San-Huang

    2013-08-14

    We present a first-principles study on the spin dependent conductance of five single-atom magnetic junctions consisting of a magnetic tip and an adatom adsorbed on a magnetic surface, i.e., the Co-Co/Co(001) and Ni-X/Ni(001) (X = Fe, Co, Ni, Cu) junctions. When their spin configuration changes from ferromagnetism to anti-ferromagnetism, the spin-up conductance increases while the spin-down one decreases. For the junctions with a magnetic adatom, there is nearly no spin valve effect as the decreased spin-down conductance counteracts the increased spin-up one. For the junction with a nonmagnetic adatom (Ni-Cu/Ni(001)), a spin valve effect is obtained with a variation of 22% in the total conductance. In addition, the change in spin configuration enhances the spin filter effect for the Ni-Fe/Ni(001) junction but suppresses it for the other junctions.

  14. Thermal conductivity studies of metal dispersed multiwalled carbon nanotubes in water and ethylene glycol based nanofluids

    SciTech Connect

    Jha, Neetu; Ramaprabhu, S.

    2009-10-15

    High thermal conducting metal nanoparticles have been dispersed on the multiwalled carbon nanotubes (MWNTs) outer surface. Structural and morphological characterizations of metal dispersed MWNTs have been carried out using x-ray diffraction analysis, high resolution transmission electron microscopy, energy dispersive x-ray analysis, and Fourier transform infrared spectroscopy. Nanofluids have been synthesized using metal-MWNTs in de-ionized water (DI water) and ethylene glycol (EG) base fluids. It has been observed that nanofluids maintain the same sequence of thermal conductivity as that of metal nanoparticles Ag-MWNTs>Au-MWNTs>Pd-MWNTs. A maximum enhancement of 37.3% and 11.3% in thermal conductivity has been obtained in Ag-MWNTs nanofluid with DI water and EG as base fluids, respectively, at a volume fraction of 0.03%. Temperature dependence study also shows enhancement of thermal conductivity with temperature.

  15. Neonatal Glycemia and Neurodevelopmental Outcomes at 2 Years

    PubMed Central

    McKinlay, Christopher J.D.; Alsweiler, Jane M.; Ansell, Judith M.; Anstice, Nicola S.; Chase, J. Geoffrey; Gamble, Gregory D.; Harris, Deborah L.; Jacobs, Robert J.; Jiang, Yannan; Paudel, Nabin; Signal, Matthew; Thompson, Benjamin; Wouldes, Trecia A.; Yu, Tzu-Ying; Harding, Jane E.

    2015-01-01

    Background Neonatal hypoglycemia is common and can cause neurologic impairment, but evidence supporting thresholds for intervention is limited. Methods We performed a prospective cohort study involving 528 neonates with a gestational age of at least 35 weeks who were considered to be at risk for hypoglycemia; all were treated to maintain a blood glucose concentration of at least 47 mg per deciliter (2.6 mmol per liter). We intermittently measured blood glucose for up to 7 days. We continuously monitored interstitial glucose concentrations, which were masked to clinical staff. Assessment at 2 years included Bayley Scales of Infant Development III and tests of executive and visual function. Results Of 614 children, 528 were eligible, and 404 (77% of eligible children) were assessed; 216 children (53%) had neonatal hypoglycemia (blood glucose concentration, <47 mg per deciliter). Hypoglycemia, when treated to maintain a blood glucose concentration of at least 47 mg per deciliter, was not associated with an increased risk of the primary outcomes of neurosensory impairment (risk ratio, 0.95; 95% confidence interval [CI], 0.75 to 1.20; P = 0.67) and processing difficulty, defined as an executive-function score or motion coherence threshold that was more than 1.5 SD from the mean (risk ratio, 0.92; 95% CI, 0.56 to 1.51; P = 0.74). Risks were not increased among children with unrecognized hypoglycemia (a low interstitial glucose concentration only). The lowest blood glucose concentration, number of hypoglycemic episodes and events, and negative interstitial increment (area above the interstitial glucose concentration curve and below 47 mg per deciliter) also did not predict the outcome. Conclusions In this cohort, neonatal hypoglycemia was not associated with an adverse neurologic outcome when treatment was provided to maintain a blood glucose concentration of at least 47 mg per deciliter. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human

  16. Media use by children younger than 2 years.

    PubMed

    Brown, Ari

    2011-11-01

    In 1999, the American Academy of Pediatrics (AAP) issued a policy statement addressing media use in children. The purpose of that statement was to educate parents about the effects that media--both the amount and the content--may have on children. In one part of that statement, the AAP recommended that "pediatricians should urge parents to avoid television viewing for children under the age of two years." The wording of the policy specifically discouraged media use in this age group, although it is frequently misquoted by media outlets as no media exposure in this age group. The AAP believed that there were significantly more potential negative effects of media than positive ones for this age group and, thus, advised families to thoughtfully consider media use for infants. This policy statement reaffirms the 1999 statement with respect to media use in infants and children younger than 2 years and provides updated research findings to support it. This statement addresses (1) the lack of evidence supporting educational or developmental benefits for media use by children younger than 2 years, (2) the potential adverse health and developmental effects of media use by children younger than 2 years, and (3) adverse effects of parental media use (background media) on children younger than 2 years. PMID:22007002

  17. 75 FR 77958 - Gravesite Reservation Survey (2 Year); Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ...-461-7485. Correction In FR Doc. 2010-30554, published on December 7, 2010, at 75 FR 76082, make the... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF VETERANS AFFAIRS Gravesite Reservation Survey (2 Year); Correction AGENCY: National Cemetery...

  18. Childhood Bereavement: Psychopathology in the 2 Years Postparental Death

    ERIC Educational Resources Information Center

    Cerel, Julie; Fristad, Mary A.; Verducci, Joseph; Weller, Ronald A.; Weller, Elizabeth B.

    2006-01-01

    Objective: Although the death of a parent is one of the most significant stressors a child can experience, the psychiatric sequelae of parental death are not fully understood. Method: A total of 360 parent-bereaved children (ages 6-17) and their surviving parents were directly interviewed four times during the first 2 years following the death (at…

  19. Detection of Flare Stars in TAOS 2-year Data

    NASA Astrophysics Data System (ADS)

    Kim, D.-W.; Protopapas, P.; Alcock, C.; Byun, Y.-I.; Zhang, Z.-W.; Wang, J.-H.; King, S.-K.; Wen, C. Y.; Lehner, M. J.; Bianco, F. B.; Coehlo, N. K.; Mondal, S.; Axelrod, T.; Chen, W. P.; Cook, K. H.; Dave, R.; de Pater, I.; Porrata, R.; Lee, T.; Lin, H.-C.; Lissauer, J. J.; Marshall, S. L.; Rice, J. A.; Schwamb, M. E.; Wang, S. Y.

    2009-04-01

    We analyzed 2 years of data from the Taiwan-American Occultation Survey (TAOS, Lehner et al. 2009), accumulated during 2005 and 2006, and found 3 flare stars. All of them are known x-ray sources. Among the detected flare stars, 1RXS J044712.8+203809 shows three recurrences of flare events within a month.

  20. Intensity Accents in French 2 Year Olds' Speech.

    ERIC Educational Resources Information Center

    Allen, George D.

    The acoustic features and functions of accentuation in French are discussed, and features of accentuation in the speech of French 2-year-olds are explored. The four major acoustic features used to signal accentual distinctions are fundamental frequency of voicing, duration of segments and syllables, intensity of segments and syllables, and…

  1. A Study of the Preparation and Properties of Antioxidative Copper Inks with High Electrical Conductivity.

    PubMed

    Tsai, Chia-Yang; Chang, Wei-Chen; Chen, Guan-Lin; Chung, Cheng-Huan; Liang, Jun-Xiang; Ma, Wei-Yang; Yang, Tsun-Neng

    2015-12-01

    Conductive ink using copper nanoparticles has attracted much attention in the printed electronics industry because of its low cost and high electrical conductivity. However, the problem of easy oxidation under heat and humidity conditions for copper material limits the wide applications. In this study, antioxidative copper inks were prepared by dispersing the nanoparticles in the solution, and then conductive copper films can be obtained after calcining the copper ink at 250 °C in nitrogen atmosphere for 30 min. A low sheet resistance of 47.6 mΩ/□ for the copper film was measured by using the four-point probe method. Importantly, we experimentally demonstrate that the electrical conductivity of copper films can be improved by increasing the calcination temperature. In addition, these highly conductive copper films can be placed in an atmospheric environment for more than 6 months without the oxidation phenomenon, which was verified by energy-dispersive X-ray spectroscopy (EDS). These observations strongly show that our conductive copper ink features high antioxidant properties and long-term stability and has a great potential for many printed electronics applications, such as flexible display systems, sensors, photovoltaic cells, and radio frequency identification. PMID:26370132

  2. In Situ Study of Strain-Dependent Ion Conductivity of Stretchable Polyethylene Oxide Electrolyte

    PubMed Central

    Kelly, Taylor; Ghadi, Bahar Moradi; Berg, Sean; Ardebili, Haleh

    2016-01-01

    There is a strong need in developing stretchable batteries that can accommodate stretchable or irregularly shaped applications including medical implants, wearable devices and stretchable electronics. Stretchable solid polymer electrolytes are ideal candidates for creating fully stretchable lithium ion batteries mainly due to their mechanical and electrochemical stability, thin-film manufacturability and enhanced safety. However, the characteristics of ion conductivity of polymer electrolytes during tensile deformation are not well understood. Here, we investigate the effects of tensile strain on the ion conductivity of thin-film polyethylene oxide (PEO) through an in situ study. The results of this investigation demonstrate that both in-plane and through-plane ion conductivities of PEO undergo steady and linear growths with respect to the tensile strain. The coefficients of strain-dependent ion conductivity enhancement (CSDICE) for in-plane and through-plane conduction were found to be 28.5 and 27.2, respectively. Tensile stress-strain curves and polarization light microscopy (PLM) of the polymer electrolyte film reveal critical insights on the microstructural transformation of stretched PEO and the potential consequences on ionic conductivity. PMID:26831948

  3. In Situ Study of Strain-Dependent Ion Conductivity of Stretchable Polyethylene Oxide Electrolyte

    NASA Astrophysics Data System (ADS)

    Kelly, Taylor; Ghadi, Bahar Moradi; Berg, Sean; Ardebili, Haleh

    2016-02-01

    There is a strong need in developing stretchable batteries that can accommodate stretchable or irregularly shaped applications including medical implants, wearable devices and stretchable electronics. Stretchable solid polymer electrolytes are ideal candidates for creating fully stretchable lithium ion batteries mainly due to their mechanical and electrochemical stability, thin-film manufacturability and enhanced safety. However, the characteristics of ion conductivity of polymer electrolytes during tensile deformation are not well understood. Here, we investigate the effects of tensile strain on the ion conductivity of thin-film polyethylene oxide (PEO) through an in situ study. The results of this investigation demonstrate that both in-plane and through-plane ion conductivities of PEO undergo steady and linear growths with respect to the tensile strain. The coefficients of strain-dependent ion conductivity enhancement (CSDICE) for in-plane and through-plane conduction were found to be 28.5 and 27.2, respectively. Tensile stress-strain curves and polarization light microscopy (PLM) of the polymer electrolyte film reveal critical insights on the microstructural transformation of stretched PEO and the potential consequences on ionic conductivity.

  4. Resistivity and Conductivity Studies of the Rattlesnake Springs, New Mexico Watershed

    NASA Astrophysics Data System (ADS)

    Santiago, C.; Doser, D. I.

    2009-12-01

    Rattlesnake Springs are a high-discharge artesian springs situated in the upper Black River Valley in southwestern Eddy Country, New Mexico. The aquifer that supplies the Rattlesnake Springs has been the main water source for domestic use by visitors of Carlsbad Caverns National Park and residents of neighboring ranches since the 1930s. Several geological studies relying on surface geology and limited water wells had previously been conducted in the area to examine the trend of ground water flow. We collected ground conductivity data at ~10m spacing around the perimeter and easily accessible areas owned by the National Park and surrounding ranches. In addition, we conducted Schlumberger and Wenner vertical electrical sounding at 10 sites, primarily to investigate the depth extend of conductivity anomalies, and a lateral resistivity survey across a suspected barrier to fluid flow. The conductivity and resistivity data indicate higher conductivities north and east of the springs reflecting moist soils, while two other highs at the eastern and western boundaries of the park are likely due to increased clay content of the soil.

  5. A Platform for the Remote Conduct of Gene-Environment Interaction Studies

    PubMed Central

    Gallacher, John; Collins, Rory; Elliott, Paul; Palmer, Stephen; Burton, Paul; Mitchell, Clive; John, Gareth; Lyons, Ronan

    2013-01-01

    Background Gene-environment interaction studies offer the prospect of robust causal inference through both gene identification and instrumental variable approaches. As such they are a major and much needed development. However, conducting these studies using traditional methods, which require direct participant contact, is resource intensive. The ability to conduct gene-environment interaction studies remotely would reduce costs and increase capacity. Aim To develop a platform for the remote conduct of gene-environment interaction studies. Methods A random sample of 15,000 men and women aged 50+ years and living in Cardiff, South Wales, of whom 6,012 were estimated to have internet connectivity, were mailed inviting them to visit a web-site to join a study of successful ageing. Online consent was obtained for questionnaire completion, cognitive testing, re-contact, record linkage and genotyping. Cognitive testing was conducted using the Cardiff Cognitive Battery. Bio-sampling was randomised to blood spot, buccal cell or no request. Results A heterogeneous sample of 663 (4.5% of mailed sample and 11% of internet connected sample) men and women (47% female) aged 50–87 years (median = 61 yrs) from diverse backgrounds (representing the full range of deprivation scores) was recruited. Bio-samples were donated by 70% of those agreeing to do so. Self report questionnaires and cognitive tests showed comparable distributions to those collected using face-to-face methods. Record linkage was achieved for 99.9% of participants. Conclusion This study has demonstrated that remote methods are suitable for the conduct of gene-environment interaction studies. Up-scaling these methods provides the opportunity to increase capacity for large-scale gene-environment interaction studies. PMID:23349852

  6. Effects of cognitive rehabilitation training on schizophrenia: 2 years of follow-up

    PubMed Central

    Tao, Jianqing; Zeng, Qiang; Liang, Jia; Zhou, Aihua; Yin, Xuebing; Xu, Ai

    2015-01-01

    Objective: Schizophrenia is a mental disorder and characterized by abnormal social behavior and failure to recognize what is real. The current study was to explore the long-term effects of cognitive rehabilitation training on schizophrenia. Methods: Eighty six cases of hospitalized patients with schizophrenia were randomly divided into study group and control group. The relapse and employment (attending school) rates were used as indicators to assess the treatment effect. All patients were followed up by 2 years. Kaplan-Meier survival analysis was conducted with relapse and employment (attending school) rates. Results: The rates of relapse in the study group and the control group were 18% and 41%, and relapse free survival time was 22.22 months and 18.55 months; the rates of employment (attending school) were 64% and 43%, and not employment (attending school) time were 10.68 months and 15.74 months, respectively. There was significant difference between the two groups (P<0.05). Conclusions: We found that the cognitive rehabilitation training could significantly reduce schizophrenic relapse rate, prolong the time of patients without relapse, improve the employment (attending school) rate, and shorten the discharged time, which is a powerful treatment method to improve social competence in schizophrenia patients. PMID:26629117

  7. Quality control in nerve conduction studies with coupled knowledge-based system approach.

    PubMed

    Xiang, Y; Eisen, A; MacNeil, M; Beddoes, M P

    1992-02-01

    Contemporary equipment used for nerve conduction studies is usually capable of computerized measurement of latency, amplitude, duration, and area of nerve and muscle action potentials and resulting conduction velocities. Abnormalities can be due to technical error or disease. Identification of technical error is a major element of quality control in electromyography, and artificial intelligence could be useful for this purpose. We have developed a coupled knowledge-based prototype system (QUALICON) to assess the correctness of recording and stimulating characteristics in routine conduction studies. QUALICON extracts numeric features from CMAPs or SNAPs, which are translated into symbolic form to drive a Bayesian network. The network uses high-level knowledge to infer the quality of stimulating and recording electrode placement as well as polarity and stimulus strength making recommendations as to the likely technical error when abnormal potentials are detected. A preliminary assessment shows that QUALICON performs as well as manual assessment performed by professionals. PMID:1549138

  8. A study of rock matrix diffusion properties by electrical conductivity measurements

    SciTech Connect

    Ohlsson, Y.; Neretnieks, I.

    1999-07-01

    Traditional rock matrix diffusion experiments on crystalline rock are very time consuming due to the low porosity and extensive analysis requirements. Electrical conductivity measurements are, on the other hand, very fast and larger samples can be used than are practical in ordinary diffusion experiments. The effective diffusivity of a non-charged molecule is readily evaluated from the measurements, and influences from surface conductivity on diffusion of cations can be studied. A large number of samples of varying thickness can be measured within a short period, and the changes in transport properties with position in a rock core can be examined. In this study the formation factor of a large number of Aespoe diorite samples is determined by electrical conductivity measurements. The formation factor is a geometric factor defined as the ratio between the effective diffusivity of a non-charged molecule, to that of the same molecule in free liquid. The variation of this factor with position among a borecore and with sample length, and its coupling to the porosity of the sample is studied. Also the surface conductivity is studied. This was determined as the residual conductivity after leaching of the pore solution ions. The formation factor of most of the samples is in the range 1E-5 to 1E-4, with a mean value of about 5E-5. Even large samples (4--13 cm) give such values. The formation factor increases with increasing porosity and the change in both formation factor and porosity with position in the borecore can be large, even for samples close to each other. The surface conductivity increases with increasing formation factor for the various samples but the influence on the pore diffusion seems to be higher for samples of lower formation factor. This suggests that the relation between the pore surface area and the pore volume is larger for samples of low formation factor.

  9. Sleep in conduct-disordered adolescents--a polysomnographic and spectral power analysis study.

    PubMed

    Lindberg, Nina; Tani, Pekka; Sailas, Eila; Virkkala, Jussi; Urrila, Anna-Sofia; Virkkunen, Matti

    2008-06-30

    The aim of the present study was to characterize sleep in conduct-disordered adolescents using polysomnography and spectral power analysis. The two hypotheses were that conduct disorder would be associated with objective sleep problems, and that conduct disorder--as a precursor of adult antisocial personality disorder--would be associated with the same kind of abnormal sleep architecture, with both increased deep sleep and delta power, as previously reported in antisocial personality disorder. The patients consisted of 15 adolescents (age range 13-17 years, mean age 14.7 years) with histories of antisocial behavior so functionally impairing that they were ordered by child welfare to undergo a psychosocial evaluation in a closed social services ward. The healthy age-matched controls comprised 20 volunteers recruited with a newspaper advertisement. Opposite to earlier subjective sleep studies among conduct-disordered children, no significant differences in sleep parameters were observed between the two groups. The adolescents with conduct disorder slept a little bit longer, but the percentage amount of different sleep stages did not differ significantly between the two groups. Relative spectral power of sleep, delta power in particular, was similar in both groups, assessed in total sleep time as well as in first half of it. Different alternative explanations for these findings are discussed. PMID:18462804

  10. USING CONTINUOUS MONITORS FOR CONDUCTING TRACER STUDIES IN WATER DISTRIBUTION SYSTEMS

    EPA Science Inventory

    The use of online monitors for conducting a distribution system tracer study is proving to be an essential tool to accurately understand the flow dynamics in a distribution system. In a series of field testing sponsored by U. S. Environmental Protection Agency (EPA) and Greater ...

  11. Qualitative Research and Educational Leadership: Essential Dynamics to Consider When Designing and Conducting Studies

    ERIC Educational Resources Information Center

    Brooks, Jeffrey S.; Normore, Anthony H.

    2015-01-01

    Purpose: The purpose of this paper is to highlight issues relayed to appropriate design and conduct of qualitative studies in educational leadership. Design/Methodology/Approach: The paper is a conceptual/logical argument that centers around the notion that while scholars in the field have at times paid attention to such dynamics, it is important…

  12. Conducting Studies of Transfer of Learning: A Practical Guide. Final Report.

    ERIC Educational Resources Information Center

    Payne, Thomas A.

    This document is a guide for use by the practical researcher concerned with conducting studies of transfer of learning from pretraining of pilots in ground-based environments to performance in aircraft. While the material addresses principally transfer of learning of pilots, many of the issues should be applicable to other contexts, to include…

  13. Meta-Analytic Synthesis of Studies Conducted at Marzano Research Laboratory on Instructional Strategies

    ERIC Educational Resources Information Center

    Haystead, Mark W.; Marzano, Robert J.

    2009-01-01

    This is a summary of 300 plus studies from Marzano Research Laboratory (MRL) on instructional strategies. This report synthesizes a series of action research projects conducted between the fall of 2004 and the spring of 2009. The data used for analysis can be found in MRL's Action Research Meta-Analysis Database. Appended are: (1) Instructions for…

  14. Conducting Case Studies of Curriculum Reform in Science and Mathematics Education.

    ERIC Educational Resources Information Center

    Anderson, Ronald D.; And Others

    The University of Colorado, under contract with the Office of Educational Research and Improvement (OERI), is conducting a study of curriculum reform in science, mathematics, and higher order thinking across the disciplines. This paper provides some of the background for this research as well as information on the conceptual framework and design…

  15. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Submission of study plans and conduct of testing. 790.62 Section 790.62 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) PROCEDURES GOVERNING TESTING CONSENT AGREEMENTS AND...

  16. 40 CFR 790.62 - Submission of study plans and conduct of testing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Submission of study plans and conduct of testing. 790.62 Section 790.62 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) PROCEDURES GOVERNING TESTING CONSENT AGREEMENTS AND TEST RULES Implementation, Enforcement...

  17. Handbook of Instructions for Conducting Follow-Up Studies of High School Graduates. Book I.

    ERIC Educational Resources Information Center

    Donaldson, Evelyn T. Comp.; And Others

    This handbook is designed to enable high schools to conduct follow-up studies on their graduates for 5 years after graduation. The information gathered should give schools pertinent data about: (1) post high school activities of graduates; (2) reactions of graduates to counseling and guidance opportunities; (3) reactions of graduates to…

  18. Treatment of Comorbid Conduct Problems and Depression in Youth: A Pilot Study

    ERIC Educational Resources Information Center

    Wolff, Jennifer C.; Ollendick, Thomas H.

    2012-01-01

    The purpose of this study was to pilot a cognitive behavioral treatment protocol for adolescents with co-occurring conduct problems and depression. A non-concurrent multiple baseline design was used to assess the effectiveness of the intervention. A sample of five adolescents, aged 11 to 14 years, participated; all five families completed the…

  19. Experimental Study on the Effective Thermal Conductivity and Thermal Diffusivity of Nanofluids

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Gu, H.; Fujii, M.

    2006-03-01

    This paper reports measurements of the effective thermal conductivity and thermal diffusivity of various nanofluids using the transient short-hot-wire technique. To remove the influences of the static charge and electrical conductance of the nanoparticles on measurement accuracy, the short-hot-wire probes are carefully coated with a pure Al2O3 thin film. Using distilled water and toluene as standard liquids of known thermal conductivity and thermal diffusivity, the length and radius of the hot wire and the thickness of the Al2O3 film are calibrated before and after application of the coating. The electrical leakage of the short-hot-wire probes is frequently checked, and only those probes that are coated well are used for measurements. In the present study, the effective thermal conductivities and thermal diffusivities of Al2O3/water, ZrO2/water, TiO2/water, and CuO/water nanofluids are measured and the effects of the volume fractions and thermal conductivities of nanoparticles and temperature are clarified. The average diameters of Al2O3, ZrO2, TiO2, and CuO particles are 20, 20, 40, and 33 nm, respectively. The uncertainty of the present measurements is estimated to be within 1% for the thermal conductivity and 5% for the thermal diffusivity. The measured results demonstrate that the effective thermal conductivities of the nanofluids show no anomalous enhancement and can be predicted accurately by the model equation of Hamilton and Crosser, when the spherical nanoparticles are dispersed into fluids.

  20. Temporal changes of topsoil hydraulic conductivity studied by multiple-point tension disk infiltrometer

    NASA Astrophysics Data System (ADS)

    Klipa, Vladimir; Zumr, David; Snehota, Michal; Dohnal, Michal

    2015-04-01

    Hydraulic conductivity of cultivated soils is strongly affected by agrotechnical procedures, soil compaction, plant growth etc. This contribution is focused on series of measurement of topsoil unsaturated hydraulic conductivity using automated multipoint tension infiltrometer developed at CTU in Prague. The apparatus consists of two triplets of minidisk infiltrometers that are supported by a light aluminum frame. Therefore it allows simultaneous measurement of six tension infiltrations at two different pressure heads. Experiments were conducted at the experimental agricultural catchment Nučice (Central Bohemia, Czech Republic) as a part of the broader research of rainfall-runoff and soil erosion processes. The soil in the catchment is classified as Cambisol with texture that is ranging from loam to clay loam and is conservatively tilled. Series of ten infiltration campaigns (56 individual infiltration experiments) were carried out on a single experimental plot during period of two years. Dataset involves measurement under various agricultural activities and crop phenophases. The hydraulic conductivities were determined using extended semiempirical estimation procedure of Zhang. Additionally, large undisturbed soil samples were analyzed with use of X-ray computed tomography to assess the soil structure morphology in detail. Results show that unsaturated hydraulic conductivity was the lowest in early spring and did increase at beginning of summer. Unsaturated soil hydraulic conductivity was higher when the soil bulk density was high. During the summer and autumn the unsaturated hydraulic conductivity remained relatively unchanged. The impact of agricultural procedures was not apparent in the dataset.. The study has been supported by the Czech Science Foundation Project No. 13-20388P and by CTU in Prague funding via Student's Grant Competition SGS No. SGS14/131/OHK1/2T/11. The MultiDisk infiltrometer was developed within the framework of the project supported by the

  1. The adult antisocial syndrome with and without antecedent conduct disorder: comparisons from an adoption study.

    PubMed

    Langbehn, D R; Cadoret, R J

    2001-01-01

    DSM antisocial personality disorder (ASPD) requires a retrospective diagnosis of conduct disorder-historical behavior not present in everyone with adult ASPD criteria. Using adoption study data, we examined the impact of this requirement on biological and environmental risk associations. We also compared clinical correlates of adult antisocial behavior with and without prior conduct disorder. We defined three subgroups: DSM-III ASPD (n = 30), adult antisocials without conduct disorder (n = 25), and controls (n = 142). By design, the sample had a high incidence of biological parent ASPD, which was partially confounded with fetal alcohol exposure. We compared the associations of both of these putative risk factors with subgroup membership after controlling for gender and adverse adoptive environment. We also examined differences in two sociopathy scales and the incidence of co-occurring affective, alcohol, and other substance use disorders. Finally, we explored differences in individual antisocial symptoms. Having an antisocial biological parent was a specific risk factor for ASPD. In contrast, fetal alcohol exposure, male gender, and adverse environment were associated with the adult antisocial syndrome, regardless of conduct disorder history. The two antisocial groups were similar with respect to sociopathy scales, co-occurring diagnoses, and the incidence of most individual symptoms. However, several adult and conduct disorder symptoms had significant specific associations with biological or environmental background or their interaction. Phenotypic expression of the biological-possibly genetic-risk for ASPD appears to be manifest before adulthood. The influence of other risk factors may not depend on antecedent conduct disorder. Despite this, we could not detect clinically important differences between the two sociopathic groups. The conduct disorder requirement therefore may be more relevant to etiological than clinical understanding of adult antisocial behavior

  2. Electrical conductivity of activated carbon-metal oxide nanocomposites under compression: a comparison study.

    PubMed

    Barroso-Bogeat, A; Alexandre-Franco, M; Fernández-González, C; Macías-García, A; Gómez-Serrano, V

    2014-12-01

    From a granular commercial activated carbon (AC) and six metal oxide (Al2O3, Fe2O3, SnO2, TiO2, WO3 and ZnO) precursors, two series of AC-metal oxide nanocomposites were prepared by wet impregnation, oven-drying at 120 °C, and subsequent heat treatment at 200 or 850 °C in an inert atmosphere. Here, the electrical conductivity of the resulting products was studied under moderate compression. The influence of the applied pressure, sample volume, mechanical work, and density of the hybrid materials was thoroughly investigated. The DC electrical conductivity of the compressed samples was measured at room temperature by the four-probe method. Compaction assays suggest that the mechanical properties of the nanocomposites are largely determined by the carbon matrix. Both the decrease in volume and the increase in density were relatively small and only significant at pressures lower than 100 kPa for AC and most nanocomposites. In contrast, the bulk electrical conductivity of the hybrid materials was strongly influenced by the intrinsic conductivity, mean crystallite size, content and chemical nature of the supported phases, which ultimately depend on the metal oxide precursor and heat treatment temperature. The supported nanoparticles may be considered to act as electrical switches either hindering or favouring the effective electron transport between the AC cores of neighbouring composite particles in contact under compression. Conductivity values as a rule were lower for the nanocomposites than for the raw AC, all of them falling in the range of semiconductor materials. With the increase in heat treatment temperature, the trend is toward the improvement of conductivity due to the increase in the crystallite size and, in some cases, to the formation of metals in the elemental state and even metal carbides. The patterns of variation of the electrical conductivity with pressure and mechanical work were slightly similar, thus suggesting the predominance of the pressure

  3. A study of phonon anisotropic scattering effect on silicon thermal conductivity at nanoscale

    SciTech Connect

    Bong, Victor N-S; Wong, Basil T.

    2015-08-28

    Previous studies have shown that anisotropy in phonon transport exist because of the difference in phonon dispersion relation due to different lattice direction, as observed by a difference in in-plane and cross-plane thermal conductivity. The directional preference (such as forward or backward scattering) in phonon propagation however, remains a relatively unexplored frontier. Our current work adopts a simple scattering probability in radiative transfer, which is called Henyey and Greenstein probability density function, and incorporates it into the phonon Monte Carlo simulation to investigate the effect of directional scattering in phonon transport. In this work, the effect of applying the anisotropy scattering is discussed, as well as its impact on the simulated thermal conductivity of silicon thin films. While the forward and backward scattering will increase and decrease thermal conductivity respectively, the extent of the effect is non-linear such that forward scattering has a more obvious effect than backward scattering.

  4. Capacitance and conductance studies on silicon solar cells subjected to 8 MeV electron irradiations

    NASA Astrophysics Data System (ADS)

    Sathyanarayana Bhat, P.; Rao, Asha; Sanjeev, Ganesh; Usha, G.; Priya, G. Krishna; Sankaran, M.; Puthanveettil, Suresh E.

    2015-06-01

    The space grade silicon solar cells were irradiated with 8 MeV electrons with doses ranging from 5-100 k Gy. Capacitance and conductance measurements were carried out in order to investigate the anomalous degradation of the cells in the radiation harsh environments and the results are presented in this paper. Detailed and systematic analysis of the frequency-dependent capacitance and conductance measurements were performed to extract the information about the interface trap states. The small increase in density of interface states was observed from the conductance-frequency measurements. The reduction in carrier concentration upon electron irradiation is due to the trapping of charge carriers by the radiation induced trap centres. The Drive Level Capacitance Profiling (DLCP) technique has been applied to study the properties of defects in silicon solar cells. A small variation in responding state densities with measuring frequency was observed and the defect densities are in the range 1015 -1016 cm-3.

  5. Diameter Dependence of Lattice Thermal Conductivity of Single-Walled Carbon Nanotubes: Study from Ab Initio.

    PubMed

    Yue, Sheng-Ying; Ouyang, Tao; Hu, Ming

    2015-01-01

    The effects of temperature, tube length, defects, and surface functionalization on the thermal conductivity (κ) of single-walled carbon nanotubes (SWCNTs) were well documented in literature. However, diameter dependence of thermal conductivity of SWCNTs received less attentions. So far, diverse trends of the diameter dependence have been discussed by different methods and all the previous results were based on empirical interatomic potentials. In this paper, we emphasize to clarify accurate κ values of SWCNTs with different diameters and in-plane κ of graphene. All the studies were under the framework of anharmonic lattice dynamics and Boltzmann transport equation (BTE) based on first principle calculations. We try to infer the right trend of diameter dependent thermal conductivity of SWCNTs. We infer that graphene is the limitation as SWCNT with an infinite diameter. We analyzed the thermal conductivity contributions from each phonon mode in SWCNTs to explain the trend. Meanwhile, we also identify the extremely low thermal conductivity of ultra-thin SWCNTs. PMID:26490342

  6. Ab initio studies on the lattice thermal conductivity of silicon clathrate frameworks II and VIII

    NASA Astrophysics Data System (ADS)

    Härkönen, Ville J.; Karttunen, Antti J.

    2016-01-01

    The lattice thermal conductivities of silicon clathrate frameworks II and VIII are investigated by using ab initio lattice dynamics and an iterative solution of the linearized Boltzmann transport equation (BTE) for phonons. Within the temperature range 100-350 K, the clathrate structures II and VIII were found to have lower lattice thermal conductivity values than the silicon diamond structure (d -Si) by factors of 1/2 and 1/3, respectively. The main reason for the lower lattice thermal conductivity of the clathrate structure II in comparison to d -Si was found to be the harmonic phonon spectra, while in the case of the clathrate structure VIII, the difference is mainly due to the harmonic phonon spectra and partly due to the shorter relaxation times of phonons. In the studied clathrate frameworks, the anharmonic effects have larger impact on the lattice thermal conductivity than the size of the unit cell. For the structure II, the predicted lattice thermal conductivity differs approximately by a factor of 20 from the previous experimental results obtained for a polycrystalline sample at room temperature.

  7. Hydraulic conductivity study of compacted clay soils used as landfill liners for an acidic waste.

    PubMed

    Hamdi, Noureddine; Srasra, Ezzeddine

    2013-01-01

    Three natural clayey soils from Tunisia were studied to assess their suitability for use as a liner for an acid waste disposal site. An investigation of the effect of the mineral composition and mechanical compaction on the hydraulic conductivity and fluoride and phosphate removal of three different soils is presented. The hydraulic conductivity of these three natural soils are 8.5 × 10(-10), 2.08 × 10(-9) and 6.8 × 10(-10)m/s for soil-1, soil-2 and soil-3, respectively. Soil specimens were compacted under various compaction strains in order to obtain three wet densities (1850, 1950 and 2050 kg/m(3)). In this condition, the hydraulic conductivity (k) was reduced with increasing density of sample for all soils. The test results of hydraulic conductivity at long-term (>200 days) using acidic waste solution (pH=2.7, charged with fluoride and phosphate ions) shows a decrease in k with time only for natural soil-1 and soil-2. However, the specimens of soil-2 compressed to the two highest densities (1950 and 2050 kg/m(3)) are cracked after 60 and 20 days, respectively, of hydraulic conductivity testing. This damage is the result of a continued increase in the internal stress due to the swelling and to the effect of aggressive wastewater. The analysis of anions shows that the retention of fluoride is higher compared to phosphate and soil-1 has the highest sorption capacity. PMID:22980909

  8. Diameter Dependence of Lattice Thermal Conductivity of Single-Walled Carbon Nanotubes: Study from Ab Initio

    PubMed Central

    Yue, Sheng-Ying; Ouyang, Tao; Hu, Ming

    2015-01-01

    The effects of temperature, tube length, defects, and surface functionalization on the thermal conductivity (κ) of single-walled carbon nanotubes (SWCNTs) were well documented in literature. However, diameter dependence of thermal conductivity of SWCNTs received less attentions. So far, diverse trends of the diameter dependence have been discussed by different methods and all the previous results were based on empirical interatomic potentials. In this paper, we emphasize to clarify accurate κ values of SWCNTs with different diameters and in-plane κ of graphene. All the studies were under the framework of anharmonic lattice dynamics and Boltzmann transport equation (BTE) based on first principle calculations. We try to infer the right trend of diameter dependent thermal conductivity of SWCNTs. We infer that graphene is the limitation as SWCNT with an infinite diameter. We analyzed the thermal conductivity contributions from each phonon mode in SWCNTs to explain the trend. Meanwhile, we also identify the extremely low thermal conductivity of ultra-thin SWCNTs. PMID:26490342

  9. Impaired small fiber conduction in patients with Fabry disease: a neurophysiological case–control study

    PubMed Central

    2013-01-01

    Background Fabry disease is an inborn lysosomal storage disorder which is associated with small fiber neuropathy. We set out to investigate small fiber conduction in Fabry patients using pain-related evoked potentials (PREP). Methods In this case–control study we prospectively studied 76 consecutive Fabry patients for electrical small fiber conduction in correlation with small fiber function and morphology. Data were compared with healthy controls using non-parametric statistical tests. All patients underwent neurological examination and were investigated with pain and depression questionnaires. Small fiber function (quantitative sensory testing, QST), morphology (skin punch biopsy), and electrical conduction (PREP) were assessed and correlated. Patients were stratified for gender and disease severity as reflected by renal function. Results All Fabry patients (31 men, 45 women) had small fiber neuropathy. Men with Fabry disease showed impaired cold (p < 0.01) and warm perception (p < 0.05), while women did not differ from controls. Intraepidermal nerve fiber density (IENFD) was reduced at the lower leg (p < 0.001) and the back (p < 0.05) mainly of men with impaired renal function. When investigating A-delta fiber conduction with PREP, men but not women with Fabry disease had lower amplitudes upon stimulation at face (p < 0.01), hands (p < 0.05), and feet (p < 0.01) compared to controls. PREP amplitudes further decreased with advance in disease severity. PREP amplitudes and warm (p < 0.05) and cold detection thresholds (p < 0.01) at the feet correlated positively in male patients. Conclusion Small fiber conduction is impaired in men with Fabry disease and worsens with advanced disease severity. PREP are well-suited to measure A-delta fiber conduction. PMID:23705943

  10. Advantages of a cohort study on cardiac arrest conducted by nurses.

    PubMed

    Campanharo, Cássia Regina Vancini; Vancini, Rodrigo Luiz; Lopes, Maria Carolina Barbosa Teixeira; Okuno, Meiry Fernanda Pinto; Batista, Ruth Ester Assayag; Atallah, Álvaro Nagib; Góis, Aécio Flávio Teixeira de

    2015-10-01

    OBJECTIVEIdentifying factors associated to survival after cardiac arrest.METHODAn experience report of a cohort study conducted in a university hospital, with a consecutive sample comprised of 285 patients. Data were collected for a year by trained nurses. The training strategy was conducted through an expository dialogue lecture. Collection monitoring was carried out by nurses via telephone calls, visits to the emergency room and by medical record searches. The neurological status of survivors was evaluated at discharge, after six months and one year.RESULTSOf the 285 patients, 16 survived until hospital discharge, and 13 remained alive after one year, making possible to identify factors associated with survival. There were no losses in the process.CONCLUSIONCohort studies help identify risks and disease outcomes. Considering cardiac arrest, they can subsidize public policies, encourage future studies and training programs for CPR, thereby improving the prognosis of patients. PMID:26516745

  11. First principles study of thermal conductivity cross-over in nanostructured zinc-chalcogenides

    SciTech Connect

    Katre, Ankita; Madsen, Georg K. H.; Togo, Atsushi; Tanaka, Isao

    2015-01-28

    Systematic first principles studies of zinc-chalcogenides have been performed to understand their thermal transport behaviour. We have applied the Boltzmann transport equation in the relaxation time approximation to calculate the thermal conductivity of ZnS, ZnSe, and ZnTe. We find a thermal conductivity cross-over between ZnS and ZnSe at nanostructure sizes around 0.1–0.2 μm and explain this in terms of the different contributions of phonon modes in these materials. We study the effect of nanostructuring using both the diffusive boundary scattering and confined mean free path limit and discuss the variations in the results. Furthermore, we show the strong influence of isotope scattering on the thermal conductivity. The calculated thermal conductivity is found to be strongly dependent on the volume and we explain the observed differences between local density and generalized gradient approximation calculations. We compare further calculated thermal properties, such as the thermal expansion coefficient, to experiment to validate our approach.

  12. Thermal conductivity of ordered-disordered material: a case study of superionic Ag2Te

    NASA Astrophysics Data System (ADS)

    Ouyang, Tao; Zhang, Xiaoliang; Hu, Ming

    2015-01-01

    Thermoelectric devices, which can generate electricity from waste heat, offer an attractive pathway for addressing an important niche in the globally growing landscape of energy demand. In the past few decades, the search for high-efficiency thermoelectrics has been guided by the concept of ‘phonon-glass electron-crystal’ (PGEC), i.e. an ideal thermoelectric material should have high carrier mobility and low thermal conductivity. Although remarkable progress has already been made along this line, the efficiency of thermoelectrics is still too poor to compete with other electricity producing methods. Ordered-disordered material, an emerging trend of high performance thermoelectrics under the concept of PGEC, is a new hot topic in the current thermoelectric research community. Taking superionic phase silver telluride (α-Ag2Te) as an example, we performed a comprehensive study of the thermal transport properties and of its physical mechanism by means of equilibrium molecular dynamic simulations. The results show that the thermal conductivity of α-Ag2Te is intrinsically very low. By analyzing the different contributions to the overall thermal conductivity, we revealed for the first time from atomistic simulations that the vibration of the Te2- sublattice dominates the thermal transport of α-Ag2Te, while the collision between the randomly diffusing Ag+ ions and the Te2- sublattice yields a significant negative contribution to the thermal transport. We also studied the effect of isotropic compressive stain and carrier concentration on the thermal conductivity of α-Ag2Te. It has been found that the thermal conductivity can be largely reduced by applying compressive strain or with stoichiometric quantity modulation. Our studies shed light on the governing mechanism of thermal transport in ordered-disordered materials and could offer useful guidance for engineering the thermal transport properties of superionic conductors in terms of enhancing their thermoelectric

  13. Students with Disabilities at 2-Year Institutions in the United States: Factors Related to Success

    ERIC Educational Resources Information Center

    Mamiseishvili, Ketevan; Koch, Lynn C.

    2012-01-01

    This study used data from the Beginning Postsecondary Students Longitudinal Study to examine the demographic and in-college characteristics of students with disabilities at 2-year institutions, identify the types of educational services available to them, and determine how students' disability conditions and their selected demographic and…

  14. Word Learning from Videos: More Evidence from 2-Year-Olds

    ERIC Educational Resources Information Center

    Allen, Rebekah; Scofield, Jason

    2010-01-01

    Young children are frequently exposed to examples of screen media like videos. The current studies asked whether videos would support word learning and whether word learning from videos might resemble word learning from a live speaker. In Study 1, 2-year-olds saw a video of a target image being labelled with a novel word and were later asked to…

  15. Comparing the similarity of responses received from studies in Amazon's Mechanical Turk to studies conducted online and with direct recruitment.

    PubMed

    Bartneck, Christoph; Duenser, Andreas; Moltchanova, Elena; Zawieska, Karolina

    2015-01-01

    Computer and internet based questionnaires have become a standard tool in Human-Computer Interaction research and other related fields, such as psychology and sociology. Amazon's Mechanical Turk (AMT) service is a new method of recruiting participants and conducting certain types of experiments. This study compares whether participants recruited through AMT give different responses than participants recruited through an online forum or recruited directly on a university campus. Moreover, we compare whether a study conducted within AMT results in different responses compared to a study for which participants are recruited through AMT but which is conducted using an external online questionnaire service. The results of this study show that there is a statistical difference between results obtained from participants recruited through AMT compared to the results from the participant recruited on campus or through online forums. We do, however, argue that this difference is so small that it has no practical consequence. There was no significant difference between running the study within AMT compared to running it with an online questionnaire service. There was no significant difference between results obtained directly from within AMT compared to results obtained in the campus and online forum condition. This may suggest that AMT is a viable and economical option for recruiting participants and for conducting studies as setting up and running a study with AMT generally requires less effort and time compared to other frequently used methods. We discuss our findings as well as limitations of using AMT for empirical studies. PMID:25876027

  16. Conduct of a personal radiofrequency electromagnetic field measurement study: proposed study protocol

    PubMed Central

    2010-01-01

    Background The development of new wireless communication technologies that emit radio frequency electromagnetic fields (RF-EMF) is ongoing, but little is known about the RF-EMF exposure distribution in the general population. Previous attempts to measure personal exposure to RF-EMF have used different measurement protocols and analysis methods making comparisons between exposure situations across different study populations very difficult. As a result, observed differences in exposure levels between study populations may not reflect real exposure differences but may be in part, or wholly due to methodological differences. Methods The aim of this paper is to develop a study protocol for future personal RF-EMF exposure studies based on experience drawn from previous research. Using the current knowledge base, we propose procedures for the measurement of personal exposure to RF-EMF, data collection, data management and analysis, and methods for the selection and instruction of study participants. Results We have identified two basic types of personal RF-EMF measurement studies: population surveys and microenvironmental measurements. In the case of a population survey, the unit of observation is the individual and a randomly selected representative sample of the population is needed to obtain reliable results. For microenvironmental measurements, study participants are selected in order to represent typical behaviours in different microenvironments. These two study types require different methods and procedures. Conclusion Applying our proposed common core procedures in future personal measurement studies will allow direct comparisons of personal RF-EMF exposures in different populations and study areas. PMID:20487532

  17. Hydraulic conductivity study of compacted clay soils used as landfill liners for an acidic waste

    SciTech Connect

    Hamdi, Noureddine; Srasra, Ezzeddine

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Examined the hydraulic conductivity evolution as function of dry density of Tunisian clay soil. Black-Right-Pointing-Pointer Follow the hydraulic conductivity evolution at long-term of three clay materials using the waste solution (pH=2.7). Black-Right-Pointing-Pointer Determined how compaction affects the hydraulic conductivity of clay soils. Black-Right-Pointing-Pointer Analyzed the concentration of F and P and examined the retention of each soil. - Abstract: Three natural clayey soils from Tunisia were studied to assess their suitability for use as a liner for an acid waste disposal site. An investigation of the effect of the mineral composition and mechanical compaction on the hydraulic conductivity and fluoride and phosphate removal of three different soils is presented. The hydraulic conductivity of these three natural soils are 8.5 Multiplication-Sign 10{sup -10}, 2.08 Multiplication-Sign 10{sup -9} and 6.8 Multiplication-Sign 10{sup -10} m/s for soil-1, soil-2 and soil-3, respectively. Soil specimens were compacted under various compaction strains in order to obtain three wet densities (1850, 1950 and 2050 kg/m{sup 3}). In this condition, the hydraulic conductivity (k) was reduced with increasing density of sample for all soils. The test results of hydraulic conductivity at long-term (>200 days) using acidic waste solution (pH = 2.7, charged with fluoride and phosphate ions) shows a decrease in k with time only for natural soil-1 and soil-2. However, the specimens of soil-2 compressed to the two highest densities (1950 and 2050 kg/m{sup 3}) are cracked after 60 and 20 days, respectively, of hydraulic conductivity testing. This damage is the result of a continued increase in the internal stress due to the swelling and to the effect of aggressive wastewater. The analysis of anions shows that the retention of fluoride is higher compared to phosphate and soil-1 has the highest sorption capacity.

  18. Guide for conducting treatability studies under CERCLA: Solvent extraction quick reference fact sheet

    SciTech Connect

    Rawe, J.

    1992-08-01

    Systematically conducted, well-documented treatability studies are an important component of remedy evaluation and selection under the Superfund Program. This fact sheet focuses on solvent extraction treatability studies, and is a highly abridged version of the guide which bears the same title. This fact sheet presents an abbreviated guide for designing and implementing solvent extraction treatability studies. The fact sheet presents a description of and discusses the applicability and limitations of solvent extraction technologies and defines the prescreening and field measurement data needed to determine if treatability testing is required.

  19. Preliminary Study on the Lesion Location and Prognosis of Cubital Tunnel Syndrome by Motor Nerve Conduction Studies

    PubMed Central

    Liu, Zhu; Jia, Zhi-Rong; Wang, Ting-Ting; Shi, Xin; Liang, Wei

    2015-01-01

    Background: To study lesions’ location and prognosis of cubital tunnel syndrome (CubTS) by routine motor nerve conduction studies (MNCSs) and short-segment nerve conduction studies (SSNCSs, inching test). Methods: Thirty healthy subjects were included and 60 ulnar nerves were studied by inching studies for normal values. Sixty-six patients who diagnosed CubTS clinically were performed bilaterally by routine MNCSs and SSNCSs. Follow-up for 1-year, the information of brief complaints, clinical symptoms, and physical examination were collected. Results: Sixty-six patients were included, 88 of nerves was abnormal by MNCS, while 105 was abnormal by the inching studies. Medial epicondyle to 2 cm above medial epicondyle is the most common segment to be detected abnormally (59.09%), P < 0.01. Twenty-two patients were followed-up, 17 patients’ symptoms were improved. Most of the patients were treated with drugs and modification of bad habits. Conclusions: (1) SSNCSs can detect lesions of compressive neuropathy in CubTS more precisely than the routine motor conduction studies. (2) SSNCSs can diagnose CubTS more sensitively than routine motor conduction studies. (3) In this study, we found that medial epicondyle to 2 cm above the medial epicondyle is the most vulnerable place that the ulnar nerve compressed. (4) The patients had a better prognosis who were abnormal in motor nerve conduction time only, but not amplitude in compressed lesions than those who were abnormal both in velocity and amplitude. Our study suggests that SSNCSs is a practical method in detecting ulnar nerve compressed neuropathy, and sensitive in diagnosing CubTS. The compound muscle action potentials by SSNCSs may predict prognosis of CubTS. PMID:25947398

  20. A facile approach for shape selective synthesis of rhodium nanostructures and conductivity studies

    SciTech Connect

    Sathe, Bhaskar R.

    2012-12-15

    Shape selective synthesis of Rh nanostructures has been demonstrated with the help of a single step chemical vapor deposition, where different shapes like cubes at 500 Degree-Sign C, pyramids and hexagons at 500 Degree-Sign C, 700 Degree-Sign C and 900 Degree-Sign C respectively have been obtained as a function of temperature. Scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and four probe conductivity measurements were used to study the morphology, crystallinity and phase purity of the structures. The conductivity values for as synthesised nanostructures have been obtained in the range of 2-7 kS/cm{sup 2}. On the basis of the experimental results, from TGA and XPS studies possible mechanistic pathway for the evolution of Rh nanostructures was discussed.

  1. Techniques for Conducting Effective Concept Design and Design-to-Cost Trade Studies

    NASA Technical Reports Server (NTRS)

    Di Pietro, David A.

    2015-01-01

    Concept design plays a central role in project success as its product effectively locks the majority of system life cycle cost. Such extraordinary leverage presents a business case for conducting concept design in a credible fashion, particularly for first-of-a-kind systems that advance the state of the art and that have high design uncertainty. A key challenge, however, is to know when credible design convergence has been achieved in such systems. Using a space system example, this paper characterizes the level of convergence needed for concept design in the context of technical and programmatic resource margins available in preliminary design and highlights the importance of design and cost evaluation learning curves in determining credible convergence. It also provides techniques for selecting trade study cases that promote objective concept evaluation, help reveal unknowns, and expedite convergence within the trade space and conveys general practices for conducting effective concept design-to-cost studies.

  2. Exploring the acceptability and feasibility of conducting a large longitudinal population-based study in Canada.

    PubMed

    Kirkland, Susan A; Raina, Parminder S; Wolfson, Christina; Strople, Geoff; Kits, Olga; Dukeshire, Steven; Angus, Camille L; Szala-Meneok, Karen; Uniat, Jennifer; Keshavarz, Homa; Furlini, Linda; Pelletier, Amélie

    2009-09-01

    ABSTRACTSuccessful recruitment and retention for population-based longitudinal studies requires understanding facilitators and barriers to participation. This study explored Canadians' views regarding one such study, the proposed Canadian Longitudinal Study on Aging (CLSA). Focus groups of participants > or =40 years of age were held in six proposed CLSA data collection sites (Halifax, Montreal, Hamilton, Winnipeg, Calgary, and Vancouver) to discuss participating in a long-term study of healthy aging. There was fundamental support for longitudinal research on health and aging. Altruism was a key motivation to participation, and universities were viewed as credible parties to conduct such studies. Participants had few worries about providing biological samples but expressed concern about potential misuse of genetic materials, commercialization of participant data, and privacy issues. These findings have already informed current, and will inform future, work on the CLSA, and will also provide useful information to researchers who undertake other population-based longitudinal studies. PMID:19860978

  3. Experimental study on subcooled flow boiling on heating surfaces with different thermal conductivities

    NASA Astrophysics Data System (ADS)

    Zou, Ling

    Subcooled flow boiling is generally characterized by high heat transfer capacity and low wall superheat, which is essential for cooling applications requiring high heat transfer rate, such as nuclear reactors and fossil boilers. In this study, subcooled flow boiling on copper and stainless steel heating surfaces was experimentally investigated from both macroscopic and microscopic points of view. Flow boiling heat flux and heat transfer coefficient were experimentally measured on both surfaces under different conditions, such as pressure, flow rate and inlet subcooling. Significant boiling heat transfer coefficient differences were found between the copper and the stainless steel heating surfaces. To explain the different flow boiling behaviors on these two heating surfaces, nucleation site density and bubble dynamics were visually observed and measured at different experimental conditions utilizing a high-speed digital video camera. These two parameters are believed to be keys in determining flow boiling heat flux. Wall superheat, critical cavity size and wall heat flux were used to correlate with nucleation site density data. Among them, wall heat flux shows the best correlation for eliminating both pressure and surface property effects. The observed nucleation site distribution shows a random distribution. When compared to the spatial Poisson distribution, similarity between them was found, while the measured nucleation site distribution is more uniform. From experimental observations, for the two surface materials investigated, which have similar surface wettability but sharply different thermal properties, bubble dynamics displayed fairly similar behavior. The obtained experimental results indicate that thermal conductivity of heating surface material plays an important role in boiling heat transfer. This is due to thermal conductivity having a significant impact on the lateral heat conduction at the heating surface and consequently temperature uniformity of

  4. An experimental study on thermal conductivity and viscosity of nanofluids containing carbon nanotubes

    PubMed Central

    2014-01-01

    Recently, there has been considerable interest in the use of nanofluids for enhancing thermal performance. It has been shown that carbon nanotubes (CNTs) are capable of enhancing the thermal performance of conventional working liquids. Although much work has been devoted on the impact of CNT concentrations on the thermo-physical properties of nanofluids, the effects of preparation methods on the stability, thermal conductivity and viscosity of CNT suspensions are not well understood. This study is focused on providing experimental data on the effects of ultrasonication, temperature and surfactant on the thermo-physical properties of multi-walled carbon nanotube (MWCNT) nanofluids. Three types of surfactants were used in the experiments, namely, gum arabic (GA), sodium dodecylbenzene sulfonate (SDBS) and sodium dodecyl sulfate (SDS). The thermal conductivity and viscosity of the nanofluid suspensions were measured at various temperatures. The results showed that the use of GA in the nanofluid leads to superior thermal conductivity compared to the use of SDBS and SDS. With distilled water as the base liquid, the samples were prepared with 0.5 wt.% MWCNTs and 0.25% GA and sonicated at various times. The results showed that the sonication time influences the thermal conductivity, viscosity and dispersion of nanofluids. The thermal conductivity of nanofluids was typically enhanced with an increase in temperature and sonication time. In the present study, the maximum thermal conductivity enhancement was found to be 22.31% (the ratio of 1.22) at temperature of 45°C and sonication time of 40 min. The viscosity of nanofluids exhibited non-Newtonian shear-thinning behaviour. It was found that the viscosity of MWCNT nanofluids increases to a maximum value at a sonication time of 7 min and subsequently decreases with a further increase in sonication time. The presented data clearly indicated that the viscosity and thermal conductivity of nanofluids are influenced by the

  5. Analytical Study on Multi-stream Heat Exchanger Include Longitudinal Heat Conduction and Parasitic Heat Loads

    NASA Astrophysics Data System (ADS)

    Zhu, Weiping; Xie, Xiujuan; Yang, Huihui; Li, Laifeng; Gong, Linghui

    High performance heat exchangers are critical component in many cryogenic systems and its performance is typically very sensitive to longitudinal heat conduction, parasitic heat loads and property variations. This paper gives an analytical study on 1-D model for multi-stream parallel-plate fin heat exchanger by using the method of decoupling transformations. The results obtained in the present paper are valuable for the reference on optimization for heat exchanger design.

  6. Conductivity study of nitrogen-doped calcium zinc oxide prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Hsu, Yu-Ting; Lan, Wen-How; Huang, Kai-Feng; Lin, Jia-Ching; Chang, Kuo-Jen

    2016-01-01

    In this study, the spray pyrolysis method was used to prepare unintentionally doped and nitrogen-doped calcium zinc oxide films by using zinc acetate, calcium nitrate precursor, and ammonium acetate precursor. Morphological and structural analyses were conducted using scanning electron microscopy and X-ray diffraction. The results indicated that film grain size decreased as the nitrogen doping was increased. Both calcium oxide and zinc oxide structures were identified in the unintentionally doped calcium zinc oxide. When nitrogen doping was introduced, the film mainly exhibited a zinc oxide structure with preferred (002) and (101) orientations. The concentration and mobility were investigated using a Hall measurement system. P-type films with a mobility and concentration of 10.6 cm2 V-1 s-1 and 2.8×1017 cm-3, respectively, were obtained. Moreover, according to a temperature-dependent conductivity analysis, an acceptor state with activation energy 0.266 eV dominated the p-type conduction for the unintentionally doped calcium zinc oxide. By contrast, a grain boundary with a barrier height of 0.274-0.292 eV dominated the hole conduction for the nitrogen-doped calcium zinc oxide films.

  7. Fluid stimulation elicits hearing in the absence of air and bone conduction-An animal study.

    PubMed

    Perez, Ronen; Adelman, Cahtia; Sohmer, Haim

    2016-04-01

    Conclusion Cochlea can be directly excited by fluid (soft-tissue) stimulation. Objective To determine whether there is no difference in auditory-nerve-brainstem evoked response (ABR) thresholds to fluid stimulation between normal and animal models of post radical-mastoidectomy, as seen in a previous human study. Background It has been shown in humans that hearing can be elicited with stimulation to fluid in the external auditory meatus (EAM), and radical-mastoidectomy cavity. These groups differed in age, initial hearing, and drilling exposure. To overcome this difference, experiments were conducted in sand-rats, first intact, and after inducing a radical-mastoidectomy. Methods The EAM of five sand-rats was filled with 0.3 ml saline. ABR thresholds were determined in response to vibratory stimulation by a clinical bone-vibrator with a plastic rod, applied to the saline in the EAM. Then the tympanic membrane was removed, and malleus dislocated (radical-mastoidectomy model). The cavity was filled with 0.45 ml saline and the ABR threshold was determined in response to vibratory stimulation to the cavity fluid. Results There was no difference in ABR fluid thresholds to EAM and mastoidectomy cavity stimulation. Air-conduction stimulation from the bone-vibrator was not involved (conductive loss due to fluid). Bone-conduction stimulation was not involved (large difference in acoustic impedance between fluid and bone). PMID:26824146

  8. Numerical study of conductive heat losses from a magmatic source at Phlegraean Fields

    NASA Astrophysics Data System (ADS)

    Di Maio, Rosa; Piegari, Ester; Mancini, Cecilia; Scandone, R.

    2015-01-01

    The thermal evolution of the Phlegraean magmatic system (southern Italy) is studied by analyzing the influence of the thermal property variations on the solution of the heat conduction equation. The aim of this paper is to verify if appropriate choices of thermal parameters can reproduce, at least to greater depths, the high temperatures measured in the geothermal wells, drilled inside the caldera, under the assumption of heat loss from a magma chamber by conduction. Since the main purpose is to verify the plausibility of such an assumption, rather simple models of the magmatic system are adopted and only major volcanic events (i.e., the Campanian Ignimbrite and the Neapolitan Yellow Tuff eruptions) are considered. The results of the simulated two-dimensional model scenarios show that by assuming an extended source region, whose emplacement time is longer than 40 ka, heat conduction mechanisms can provide temperatures as high as those measured at depths deeper than about 2000 m. On the other hand, the 1D simulations show that appropriate choices for the thermal conductivity depth profiles can reproduce the observed temperatures at depths deeper than about 1000 m. These findings question the apparent consensus that convection is the only dominant form of heat transfer at Phlegraean Fields and might motivate new research for reconstructing the thermal evolution of the Phlegraean magmatic system.

  9. Parallel plate waveguide time domain spectroscopy to study terahertz conductivity of utltrathin materials

    NASA Astrophysics Data System (ADS)

    Razanoelina, Manjakavahoaka; Bagsican, Filchito R.; Kawayama, Iwao; Zhang, Xiang; Ma, Lulu; Murakami, Hironaru; Vajtai, Robert; Ajayan, Pulickel M.; Kono, Junichiro; Mittleman, Daniel M.; Tonouchi, Masayoshi

    2016-04-01

    The newly discovered atomically thin and layered materials which host electronic system that respond to longwavelength light in extraordinary manner can lead to a major breakthrough in the field of terahertz (THz) optics and photonics. However, their low conductivities due to either low densities or low mobility make it challenging to characterize their basic THz properties with the standard spectroscopic method. Here, we develop a THz spectroscopic technique based on parallel plate waveguide (PPWG) to overcome the limitations of the conventional THz time domain spectroscopy (TDS) technique. The present method is particularly suitable to ultrathin conductive materials with low carrier density. We report in details the derivation of the dispersion equations of the terahertz wave propagation in a PPWG loaded by a thin conductive materials with zero-thickness. These dispersion equations for transverse magnetic (TM) and transverse electric (TE) waveguide modes are the core of the optical parameters extraction algorithm in the THz-PPWG-TDS analysis. We demonstrate the effectiveness of the waveguide approach by characterizing low conductive CVD graphene. The high sensitivity of THz-PPWG-TDS technique enables us to study the carrier dynamics in graphene with Drude and Drude-Smith model.

  10. Impact of Living Environment on 2-Year Mortality in Elderly Maintenance Hemodialysis Patients

    PubMed Central

    Huang, Wen-Hung; Lin, Ja-Liang; Lin-Tan, Dan-Tzu; Chen, Kuan-Hsing; Hsu, Ching-Wei; Yen, Tzung-Hai

    2013-01-01

    Background Studies on risk factors of mortality in elderly patients with hemodialysis usually focus on comorbidities, nutrition, and inflammation. Discussion on the correlation between living environment and mortality of these patients is limited. Methods A total of 256 elderly hemodialysis patients participated in this 2-year prospective observational study. The subjects were divided into 2 subgroups based on whether they were living in Taipei Basin (n = 63) or not (n = 193). Demographic, hematological, nutritional, inflammatory, biochemical, and dialysis-related data were obtained for cross-sectional analysis. Causes of death and mortality rates were also analyzed for each subgroup. Results Patients in the basin group had a higher incidence of combined protein-energy wasting and inflammation than those in the around basin group. At the end of the 2-year follow-up, 68 patients had died. Univariate binary logistic regression analysis revealed that a very advanced age, basin group, serum albumin levels, serum creatinine levels, non-anuria, and the complications of stroke and CAD were associated with 2-year mortality. Meanwhile, log high-sensitivity C-reactive protein (hs-CRP) levels were not associated with 2-year mortality. Multivariate Cox regression analysis revealed that basin group, serum albumin levels, and the complications of stroke and CAD were significant risk factors for 2-year mortality in these patients. Conclusion The results of this study indicate that factors such as living in the Taipei Basin with higher air pollutant levels in elderly hemodialysis patients is associated with protein-energy wasting and inflammation, as well as 2-year mortality. These findings suggest that among this population, living environment is as important as comorbidities and nutrition. Furthermore, air pollution should be getting more attention especially in the overcrowding Basin topography. PMID:24058552

  11. Multidrug-resistant tuberculosis that required 2 years for diagnosis.

    PubMed

    Yano, Shuichi; Kobayashi, Kanako; Ikeda, Toshikazu

    2012-01-01

    Isoniazid (H) or rifampicin (R) mono-resistant disease can be treated easily and effectively with first-line drugs, while combined H and R resistance (ie, multidrug-resistant tuberculosis (MDRTB)) requires treatment with at least four agents, including a quinolone and an injectable agent. Drug-resistant Mycobacterium tuberculosis strains are reported to be extremely difficult to cultivate invitro. The authors report a case of MDRTB that required 2 years for diagnosis, and was detected only in sputum culture on solid medium. Physicians should consider MDRTB if TB is suspected but pathogens are not detected. PMID:22605803

  12. Studies and projections of hydraulic conductivity of Devonian Plavinu and Daugava carbonate aquifers in Latvia

    NASA Astrophysics Data System (ADS)

    Perkone, E.; Delina, A.; Saks, T.; Raga, B.; Jātnieks, J.; Klints, I.; Popovs, K.; Babre, A.; Bikše, J.; Kalvāns, A.; Retike, I.; Ukass, J.

    2012-04-01

    Carbonate aquifers show a very wide range of hydrogeological characteristics. Carbonate rock hydrogeology display two extremes: on one hand hydrogeological properties of the carbonates are governed by the pathways of the preferential groundwater flow typical in karstic regions, on the other - some carbonate aquifers behave almost like a homogeneous, isotropic, porous medium. Most lie between these extremes, but these case variations complicates the study of carbonate aquifer properties. In this study the results of the hydraulic conductivity in carbonate aquifers measurements, hydraulic conductivity correlation between sediments lithology and the aquifer surface depth and fractures research is presented. Upper Devonian Frasnian stage Pļaviņu and Daugava carbonate aquifers in the Latvian part of the Baltic basin is considered. The aim of this research is to elaborate characteristic hydraulic conductivity values for each aquifer based on existing data of the pumping test results and other aquifer properties. Pļaviņu and Daugava carbonate aquifers mainly consist of jointed dolomite with intermediate layers of dolomitic marlstone, limestone, clays and gypsum. These aquifers are prevalent in most of the study area, except Northern and South - Eastern parts of the territory. In geological structure Daugava aquifer lies above Pļaviņu aquifer. Daugava aquifer depth changes from 10 - 20 and even less meters in Eastern part to 250 - 300 m in South - West part of study area, but thickness varies from few meters to 30 m. Pļaviņu aquifer surface depth varies from 20 - 30 m, but in uplands surface depth reaches more than 120 m, in Eastern part to more than 300 m in South - West part of study area. Aquifer average thickness varies from 20 - 40 m, but in areas with buried valleys thickness can be less than 10 meters. Outcrops of these sediments are occurring in banks of largest rivers and in some areas aquifers are karstified. In studies of the carbonate aquifers it is

  13. Molecular dynamics simulation of effective thermal conductivity and study of enhanced thermal transport mechanism in nanofluids

    NASA Astrophysics Data System (ADS)

    Sarkar, Suranjan; Selvam, R. Panneer

    2007-10-01

    Nanofluids have been proposed as a route for surpassing the performance of currently available heat transfer liquids in the near future. In this study an equilibrium molecular dynamics simulation was used to model a nanofluid system. The thermal conductivity of the base fluid and nanofluid was computed using the Green-Kubo method for various volume fractions of nanoparticle loadings. This study showed the ability of molecular dynamics to predict the enhanced thermal conductivity of nanofluids. Through molecular dynamics calculation of mean square displacements for liquid phase in base fluid and for liquid and solid phases in nanofluid, this study tried to investigate the mechanisms involved in thermal transport of nanofluids at the atomic level. The result showed that the thermal transport enhancement of nanofluids was mostly due to the increased movement of liquid atoms in the presence of nanoparticle. Diffusion coefficients were also calculated for base fluid and nanofluids. Similarity of enhancement in thermal conductivity and diffusion coefficient for nanofluids indicates similar transport process for mass and heat.

  14. Diagnosis of Severe Carpal Tunnel Syndrome Using Nerve Conduction Study and Ultrasonography.

    PubMed

    Fujimoto, Kazuhiro; Kanchiku, Tsukasa; Kido, Kenji; Imajo, Yasuaki; Funaba, Masahiro; Taguchi, Toshihiko

    2015-10-01

    This study investigated the correlation between nerve conduction study and ultrasonographic findings for assessment of the usefulness of ultrasonography in determining carpal tunnel syndrome severity. Hands of adults with carpal tunnel syndrome were assessed using ultrasound and nerve conduction studies and grouped according to median nerve cross-sectional area (CSA). There were significant differences (p < 0.01) in mean median nerve CSA between controls, patients with median sensory nerve conduction velocity ≤40 m/s and patients with absent sensory nerve action potential and between controls, patients with median nerve distal motor latency ≥4.5 ms and patients with absent compound muscle action potentials of the abductor pollicis brevis. This is the first report to define median nerve CSA cutoff values (18 mm(2)) for determining carpal tunnel syndrome severity in patients with absent compound muscle action potentials of the abductor pollicis brevis. Median nerve CSA values below the cutoff values should prompt clinicians to consider other disorders, such as cervical compressive myelopathy. PMID:26111913

  15. Study of the solution thermal conductivity effect on nonlinear refraction of colloidal gold nanoparticles

    NASA Astrophysics Data System (ADS)

    Sarkhosh, L.; Mansour, N.

    2015-06-01

    In nanoparticle colloidal systems, the thermal nonlinearity is affected by the thermal parameters of the surrounding solution. Having a low temperature gradient rate solution may be a key factor in producing high thermal nonlinear properties in colloids. In this manuscript, the effect of the thermal conductivity of the surrounding liquid environment on the thermal nonlinear refraction of gold nanoparticles (AuNPs) synthesized by laser ablation of a gold target in different solutions is investigated. Gold nanoparticles colloids have been fabricated by the nanosecond pulsed laser ablation of a pure gold plate in different liquid environments with a thermal conductivity range of 0.14-0.60 W mK-1 including cyclohexanone, castor oil, dimethyl sulfoxide, ethylene glycol, glycerin and water. The AuNPs colloids exhibit a UV-Vis absorption spectrum with a surface plasmon absorption peak at about 540  ±  20 nm. The thermal nonlinear optical responses of the gold colloids are measured using the Z-scan technique under low power CW laser irradiation at 532 nm near the surface plasmon peak of the nanoparticles. Our results show that the nonlinear refractive index of the nanoparticle colloids is considerably affected by the thermal conductivity of liquid medium. The largest nonlinear refractive index of -3.1  ×  10-7 cm2 W-1 is obtained for AuNP in cyclohexanone with the lowest thermal conductivity of 0.14 W mK-1 whereas the lowest one of -0.1  ×  10-7 cm2 W-1 is obtained for AuNP in water with the highest thermal conductivity of 0.60 W mK-1. This study shows that the nonlinear refractive index value of colloids can be controlled by the thermal conductivity of the used liquid’s environment. This allows us to design low threshold optical limiters by choosing a solution with low thermal conductivity for colloidal nanoparticles.

  16. Hispanic Student Enrollment and Educational Attainment in Texas 2-Year Colleges: A Multi-Year Statewide Analysis

    ERIC Educational Resources Information Center

    Hernandez, Jack

    2012-01-01

    Purpose: The purpose of the study was to examine the numbers and percentages of Hispanic college students enrolled in Texas 2-year colleges from the 2000 through the 2011 academic years and to examine the numbers and percentages of Hispanic students obtaining associate degrees from Texas 2-year colleges for the 2000 through the 2011 academic…

  17. Analytical study of electrophoretic characterization of kidney cells. [conducted during the Apollo Soyuz Test Project

    NASA Technical Reports Server (NTRS)

    Knox, R. J.

    1978-01-01

    Embryonic kidney cells were studied as a follow-up to the MA-011 Electrophoresis Technology Experiment which was conducted during the Apollo Soyuz Test Project (ASTP). The postflight analysis of the performance of the ASTP zone electrophoresis experiment involving embryonic kidney cells is reported. The feasibility of producing standard particles for electrophoresis was also studied. This work was undertaken in response to a need for standardization of methods for producing, calibrating, and storing electrophoretic particle standards which could be employed in performance tests of various types of electrophoresis equipment. Promising procedures were tested for their suitability in the production of standard test particles from red blood cells.

  18. Study of the electrical conductivity at finite temperature in 2D Si- MOSFETs

    SciTech Connect

    Limouny, L. Kaaouachi, A. El Tata, O.; Daoudi, E.; Errai, M.; Dlimi, S.; Idrissi, H. El; Zatni, A.

    2014-01-27

    We investigate the low temperature density dependent conductivity of two dimensional electron systems in zero magnetic field for sample Si-15 MOSFETs. The first purpose of this paper is to establish that the knee of the conductivity σ{sub 0} (σ{sub 0} is the T = 0.3 conductivity obtained by linear extrapolation of the curves of σ (T) for different values of electron density, n{sub s}) as a function of the carrier densities n{sub s} for T = 0.3 K, observed by Lai et al. and Limouny et al. in previous work for two different samples, is independent of temperature. The second aim is the determination of the critical density, n{sub c}, of the metal-insulator transition. Many methods are used in this investigation of n{sub c} which have been already used for other samples. The motivation behind this last study is the observation of many values of n{sub c} that have been obtained from different methods and that are slightly different. We will use in this study three methods with the intention to infer which one is more appropriate to obtain n{sub c}.

  19. Conductive Education as a Method of Stroke Rehabilitation: A Single Blinded Randomised Controlled Feasibility Study

    PubMed Central

    Jutley-Neilson, Jagjeet; Russell, Nicholas C. C.; Sackley, Catherine M.

    2016-01-01

    Background. Conductive Education for stroke survivors has shown promise but randomised evidence is unavailable. This study assessed the feasibility of a definitive randomised controlled trial to evaluate efficacy. Methods. Adult stroke survivors were recruited through local community notices. Those completing the baseline assessment were randomised using an online program and group allocation was independent. Intervention group participants received 10 weekly 1.5-hour sessions of Conductive Education at the National Institute of Conductive Education in Birmingham, UK. The control group participants attended two group meetings. The study evaluated the feasibility of recruitment procedures, delivery of the intervention, retention of participants, and appropriateness of outcome measures and data collection methods. Independent assessments included the Barthel Index, the Stroke Impact Scale, the Timed Up and Go test, and the Hospital Anxiety and Depression Scale. Results. Eighty-two patients were enrolled; 77 completed the baseline assessment (46 men, mean age 62.1 yrs.) and were randomised. 70 commenced the intervention (n = 37) or an equivalent waiting period (n = 33). 32/37 completed the 10-week training and 32/33 the waiting period. There were no missing items from completed questionnaires and no adverse events. Discussion. Recruitment, intervention, and assessment methods worked well. Transport issues for intervention and assessment appointments require review. Conclusion. A definitive trial is feasible. This trial is registered with ISRCTN84064492. PMID:27418997

  20. A feasibility study of conducting the Montreal Cognitive Assessment remotely in individuals with movement disorders.

    PubMed

    Abdolahi, Amir; Bull, Michael T; Darwin, Kristin C; Venkataraman, Venayak; Grana, Matthew J; Dorsey, E Ray; Biglan, Kevin M

    2016-06-01

    Remote assessments of individuals with a neurological disease via telemedicine have the potential to reduce some of the burdens associated with clinical care and research participation. We aim to evaluate the feasibility of conducting the Montreal Cognitive Assessment remotely in individuals with movement disorders. A pilot study derived from two telemedicine trials was conducted. In total, 17 individuals with movement disorders (8 with Parkinson disease and 9 with Huntington disease) had Montreal Cognitive Assessment examinations evaluated in-person and remotely via web-based video conferencing to primarily determine feasibility and potential barriers in its remote administration. Administering the Montreal Cognitive Assessment remotely in a sample of movement disorder patients with mild cognitive impairment is feasible, with only minor common complications associated with technology, including delayed sound and corrupted imaging for participants with low connection speeds. The Montreal Cognitive Assessment has the potential to be used in remote assessments of patients and research participants with movement disorders. PMID:25391849

  1. Compensated Arrhenius formalism applied to a conductivity study in poly(propylene glycol) diacrylate monomers

    NASA Astrophysics Data System (ADS)

    Dubois, F.; Derouiche, Y.; Leblond, J. M.; Maschke, U.; Douali, R.

    2015-09-01

    The temperature dependence of the ionic conductivity is studied in a series of poly(propylene glycol) diacrylate monomers. The experimental data are analyzed by means of the approach recently proposed by Petrowsky et al. [J. Phys. Chem. B. 113, 5996 (2009), 10.1021/jp810095g]. This so-called compensated Arrhenius formalism (CAF) approach takes into account the influence of the dielectric permittivity on the exponential prefactor in the classical Arrhenius equation. The experimental data presented in this paper show a good agreement with the CAF; this means that the exponential prefactor is principally dielectric permittivity dependent. The compensated data revealed two conduction processes with different activation energies; they correspond to low and high temperature ranges, respectively.

  2. Magnetohydrodynamic flow of Sisko fluid over a stretching cylinder with variable thermal conductivity: A numerical study

    NASA Astrophysics Data System (ADS)

    Malik, M. Y.; Hussain, Arif; Salahuddin, T.; Awais, M.; Bilal, S.

    2016-02-01

    In present study effects of magnetic field and variable thermal conductivity on Sisko fluid model are analyzed. The modeled partial differential equations are simplified by boundary layer approach. Appropriate similarity transformations are applied to transform governing partial differential equations into ordinary differential equations. Then these equations are solved numerically by shooting method in combination with Runge-Kutta-Fehlberg method. Comparison between present and previous computed results is presented via tables. The variations in fluid velocity and temperature are displayed through graphs for different values of Sisko fluid parameter, curvature parameter, magnetic field parameter, thermal conductivity parameter and Prandtl number. The effects of physical parameters on skin friction coefficient and local Nusselt number are exhibited with figures and tables.

  3. Compensated Arrhenius formalism applied to a conductivity study in poly(propylene glycol) diacrylate monomers.

    PubMed

    Dubois, F; Derouiche, Y; Leblond, J M; Maschke, U; Douali, R

    2015-09-01

    The temperature dependence of the ionic conductivity is studied in a series of poly(propylene glycol) diacrylate monomers. The experimental data are analyzed by means of the approach recently proposed by Petrowsky et al. [J. Phys. Chem. B. 113, 5996 (2009)10.1021/jp810095g]. This so-called compensated Arrhenius formalism (CAF) approach takes into account the influence of the dielectric permittivity on the exponential prefactor in the classical Arrhenius equation. The experimental data presented in this paper show a good agreement with the CAF; this means that the exponential prefactor is principally dielectric permittivity dependent. The compensated data revealed two conduction processes with different activation energies; they correspond to low and high temperature ranges, respectively. PMID:26465489

  4. AC conductivity and electrochemical studies of PVA/PEG based polymer blend electrolyte films

    NASA Astrophysics Data System (ADS)

    Polu, Anji Reddy; Kumar, Ranveer; Dehariya, Harsha

    2012-06-01

    Polymer blend electrolyte films based on Polyvinyl alcohol(PVA)/Poly(ethylene glycol)(PEG) and magnesium nitrate (Mg(NO3)2) were prepared by solution casting technique. Conductivity in the temperature range 303-373 K and transference number measurements have been employed to investigate the charge transport in this polymer blend electrolyte system. The highest conductivity is found to be 9.63 × 10-5 S/cm at 30°C for sample with 30 weight percent of Mg(NO3)2 in PVA/PEG blend matrix. Transport number data shows that the charge transport in this polymer electrolyte system is predominantly due to ions. Using this electrolyte, an electrochemical cell with configuration Mg/(PVA+PEG+Mg(NO3)2)/(I2+C+electrolyte) was fabricated and its discharge characteristics profile has been studied.

  5. Atomistic study of dynamics for metallic filament growth in conductive-bridge random access memory.

    PubMed

    Qin, Shengjun; Liu, Zhan; Zhang, Guo; Zhang, Jinyu; Sun, Yaping; Wu, Huaqiang; Qian, He; Yu, Zhiping

    2015-04-14

    The growth dynamics for metallic filaments in conductive-bridge resistive-switching random access memory (CBRAM) are studied using the kinetic Monte Carlo (KMC) method. The physical process at the atomistic level is revealed in explaining the experimental observation that filament growth can originate at either the cathode or the anode. The statistical nature of the filament growth is best shown by the random topography of dendrite-like conductive paths obtained. Critical material properties, such as charged-particle mobility in the switching layer of a solid electrolyte or a dielectric, are mapped to KMC model parameters through activation energy, etc. The accuracy of the simulator is established by the good agreement between the simulated forming time and the measured data. PMID:25750983

  6. Improving the electrical conductivity of carbon nanotube networks: a first-principles study.

    PubMed

    Li, Elise Y; Marzari, Nicola

    2011-12-27

    We address the issue of the low electrical conductivity observed in carbon nanotube networks using first-principles calculations of the structure, stability, and ballistic transport of different nanotube junctions. We first study covalent linkers, using the nitrene-pyrazine case as a model for conductance-preserving [2 + 1] cycloadditions, and discuss the reasons for their poor performance. We then characterize the role of transition-metal adsorbates in improving mechanical coupling and electrical tunneling between the tubes. We show that the strong hybridization between the transition-metal d orbitals with the π orbitals of the nanotube can provide an excellent electrical bridge for nanotube-nanotube junctions. This effect is maximized in the case of nitrogen-doped nanotubes, thanks to the strong mechanical coupling between the tubes mediated by a single transition metal adatom. Our results suggest effective strategies to optimize the performance of carbon nanotube networks. PMID:22059779

  7. Biological studies and electrical conductivity of paper sheet based on PANI/PS/Ag-NPs nanocomposite.

    PubMed

    Youssef, A M; Mohamed, S A; Abdel-Aziz, M S; Abdel-Aziz, M E; Turky, G; Kamel, S

    2016-08-20

    Polyaniline (PANI) with/without polystyrene (PS), was successfully manufactured in the occurrence of dispersed pulp fibers via the oxidative polymerization reaction of aniline monomer to produce conductive paper sheets containing PANI, PANI/PS composites. Additionally, sliver nitrate (Ag-NO3) was added by varied loadings to the oxidative polymerization of aniline monomer to provide sliver nanoparticles (Ag-NPs) emptied into the prepared paper sheets. The prepared paper sheets were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD) and infrared spectroscopy (IR), the mechanical properties of the prepared paper sheets were evaluated. Moreover, the electrical conductivity and biological studies such as cellulases assay, Microorganism & culture condition and detection of the released of Ag-NPs were evaluated. Furthermore, the prepared paper sheets were displayed good antibacterial properties contrary to gram positive and gram negative bacteria. Consequently, the prepared paper sheet may be used as novel materials for packaging applications. PMID:27178939

  8. Behavior Predictors of Language Development over 2 Years in Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Bopp, Karen D.; Mirenda, Pat; Zumbo, Bruno D.

    2009-01-01

    Purpose: This exploratory study examined predictive relationships between 5 types of behaviors and the trajectories of vocabulary and language development in young children with autism over 2 years. Method: Participants were 69 children with autism assessed using standardized measures prior to the initiation of early intervention (T1) and 6 months…

  9. THE PSYCHOLOGICAL IMPACT OF THE PUBLIC 2-YEAR COLLEGE ON CERTAIN NONINTELLECTUAL FUNCTIONS.

    ERIC Educational Resources Information Center

    PLANT, WALTER T.; TELFORD, CHARLES W.

    THIS STUDY SOUGHT TO DETERMINE IF THERE ARE SIGNIFICANT CHANGES IN SELECTED PERSONALITY TRAITS, IDEOLOGIES, AND VALUES OF STUDENTS WHO ATTEND A 2-YEAR PUBLIC JUNIOR COLLEGE. A BATTERY OF PSYCHOLOGICAL TESTS WAS ADMINISTERED TO ALL PERSONS APPLYING FOR ADMISSION AS COLLEGE FRESHMEN FOR THE FALL SEMESTER OF 1960 AT ONE OF SIX CALIFORNIA PUBLIC…

  10. Emotionally Focused Interventions for Couples with Chronically Ill Children: A 2-Year Follow-Up

    ERIC Educational Resources Information Center

    Cloutier, Paula F.; Manion, Ian G.; Walker, Jan Gordon; Johnson, Susan M.

    2002-01-01

    Couples with chronically ill children are particularly at risk for experiencing marital distress. The study presented here is a 2-year follow-up of a randomized control trial that assessed the efficacy of Emotionally Focused Therapy (EFT) in decreasing marital distress in a sample of couples with a chronically ill child. Thirteen couples with…

  11. Phonetic Modification of Vowel Space in Storybook Speech to Infants up to 2 Years of Age

    ERIC Educational Resources Information Center

    Burnham, Evamarie B.; Wieland, Elizabeth A.; Kondaurova, Maria V.; McAuley, J. Devin; Bergeson, Tonya R.; Dilley, Laura C.

    2015-01-01

    Purpose: A large body of literature has indicated vowel space area expansion in infant-directed (ID) speech compared with adult-directed (AD) speech, which may promote language acquisition. The current study tested whether this expansion occurs in storybook speech read to infants at various points during their first 2 years of life. Method: In 2…

  12. Administration of high-dose interleukin-2 in a 2-year-old with metastatic melanoma.

    PubMed

    Bernhardt, M Brooke; Hicks, M John; Pappo, Alberto S

    2009-12-15

    Malignant melanoma is rare in pediatrics, and therapies for patients with disseminated disease have not been well studied. This report describes our experience with the use of high-dose interleukin 2 (aldesleukin, IL-2) in a 2-year-old child with metastatic melanoma and describes our approach for the administration of this agent to young patients. PMID:19731326

  13. How Are 2-Year US Colleges Addressing Student Alcohol Use and Related Problems?

    ERIC Educational Resources Information Center

    Lenk, Kathleen M.; Nelson, Toben F.; Erickson, Darin J.; Toomey, Traci L.

    2015-01-01

    A considerable amount of attention and research has been dedicated to addressing alcohol use and related problems among students at 4-year colleges; however, less attention has been given to alcohol-related issues among students at 2-year technical/community colleges. This article describes research that expands on a study by Chiauzzi and…

  14. How Joint Attention Relates to Cooperation in 1- and 2-Year-Olds

    ERIC Educational Resources Information Center

    Wu, Zhen; Pan, Jingtong; Su, Yanjie; Gros-Louis, Julie

    2013-01-01

    Joint attention has been suggested to contribute to children's development of cooperation; however, few empirical studies have directly tested this hypothesis. Children aged 1 and 2 years participated in two joint action activities to assess their cooperation with an adult partner, who stopped participating at a specific moment during the…

  15. Attitudes of College Students Enrolled in 2-Year Health Care Programs towards Online Learning

    ERIC Educational Resources Information Center

    Abdulla, Dalya

    2012-01-01

    Colleges offering 2-year diplomas to high-school graduates were among the forefront leaders in online learning however studies illustrating appropriate course construction for such student populations are scarce. Pharmacy Math (MATH16532) is a core course for students enrolled in the Practical Nursing (PN) and Pharmacy Technician (PT) programs at…

  16. Developmental Assessment of Preterm Infants at 2 Years: Validity of Parent Reports

    ERIC Educational Resources Information Center

    Johnson, Samantha; Wolke, Dieter; Marlow, Neil

    2008-01-01

    Parental questionnaires are inexpensive alternatives to standardized testing for outcome measurement. The Parent Report of Children's Abilities has previously been revised (PARCA-R) and validated for use with very-preterm infants at 2 years of age. This study revalidated the PARCA-R for assessing cognition in a larger and more inclusive sample of…

  17. Impedance study of tea with added taste compounds using conducting polymer and metal electrodes.

    PubMed

    Dhiman, Mopsy; Kapur, Pawan; Ganguli, Abhijit; Singla, Madan Lal

    2012-09-01

    In this study the sensing capabilities of a combination of metals and conducting polymer sensing/working electrodes for tea liquor prepared by addition of different compounds using an impedance mode in frequency range 1 Hz-100 KHz at 0.1 V potential has been carried out. Classification of six different tea liquor samples made by dissolving various compounds (black tea liquor + raw milk from milkman), (black tea liquor + sweetened clove syrup), (black tea liquor + sweetened ginger syrup), (black tea liquor + sweetened cardamom syrup), (black tea liquor + sweet chocolate syrup) and (black tea liquor + vanilla flavoured milk without sugar) using six different working electrodes in a multi electrode setup has been studied using impedance and further its PCA has been carried out. Working electrodes of Platinum (Pt), Gold (Au), Silver (Ag), Glassy Carbon (GC) and conducting polymer electrodes of Polyaniline (PANI) and Polypyrrole (PPY) grown on an ITO surface potentiostatically have been deployed in a three electrode set up. The impedance response of these tea liquor samples using number of working electrodes shows a decrease in the real and imaginary impedance values presented on nyquist plots depending upon the nature of the electrode and amount of dissolved salts present in compounds added to tea liquor/solution. The different sensing surfaces allowed a high cross-selectivity in response to the same analyte. From Principal Component Analysis (PCA) plots it was possible to classify tea liquor in 3-4 classes using conducting polymer electrodes; however tea liquors were well separated from the PCA plots employing the impedance data of both conducting polymer and metal electrodes. PMID:23035436

  18. Studies of liquid adsorption, condensation and surface conductivity in porous media

    NASA Astrophysics Data System (ADS)

    Qi, Hao

    bulk, thereby more accurate estimates of oil saturation can be achieved in using the empirical Archie's relation. Our studies shed more light on the various aspects of the surface ionic conduction, including Debye - Huckle length, CPA phenomenon, and effects of saturation, cation species, temperature, and substrate.

  19. A theoretical study of wave dispersion and thermal conduction for HMX/additive interfaces

    NASA Astrophysics Data System (ADS)

    Long, Yao; Chen, Jun

    2014-04-01

    The wave dispersion rule for non-uniform material is useful for ultrasonic inspection and engine life prediction, and also is key in achieving an understanding of the energy dissipation and thermal conduction properties of solid material. On the basis of linear response theory and molecular dynamics, we derive a set of formulas for calculating the wave dispersion rate of interface systems, and study four kinds of interfaces inside plastic bonded explosives: HMX/{HMX, TATB, F2312, F2313}. (HMX: octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine; TATB: 1,3,5-triamino-2,4,6-trinitrobenzene; F2312, F2313: fluoropolymers). The wave dispersion rate is obtained over a wide frequency range from kHz to PHz. We find that at low frequency, the rate is proportional to the square of the frequency, and at high frequency, the rate couples with the molecular vibration modes at the interface. By using the results, the thermal conductivities of HMX/additive interfaces are derived, and a physical model is built for describing the total thermal conductivity of mixture explosives, including HMX multi-particle systems and {TATB, F2312, F2313}-coated HMX.

  20. Current at domain walls, roughly speaking: nanoscales studies of disorder roughening and conduction

    NASA Astrophysics Data System (ADS)

    Paruch, Patrycja

    2013-03-01

    Domain walls in (multi)ferroic materials are the thin elastic interfaces separating regions with different orientations of magnetisation, electric polarisation, or spontaneous strain. Understanding their behaviour, and controlling domain size and stability, is key for their integration into applications, while fundamentally, domain walls provide an excellent model system in which the rich physics of disordered elastic interfaces can be accesses. In addition, domain walls can present novel properties, quite different from those of their parent materials, making them potentially useful as active components in future nano-devices. Here, we present our atomic force microscopy studies of ferroelectric domain walls in epitaxial Pb(Zr0.2Ti0.8)O3 and BiFeO3 thin films, in which we use piezorespose force microscopy to show unusual domain wall roughening behaviour, with very localised disorder regions in the sample leading to a complex, multi-affine scaling of the domain wall shape. We also show the effects of temperature, environmental conditions, and defects on switching dynamics and domain wall roughness. We combine these observations with parallel conductive-tip atomic force microscopy current measurements, which also show highly localised variations in conduction, and highlight the key role played by oxygen vacancies in the observed domain wall conduction.

  1. Multifocal motor neuropathy with conduction block: a study of 24 patients.

    PubMed Central

    Bouche, P; Moulonguet, A; Younes-Chennoufi, A B; Adams, D; Baumann, N; Meininger, V; Léger, J M; Said, G

    1995-01-01

    Twenty four patients with pure motor neuropathy are reported. The chronic motor involvement associated with fasciculations and cramps, mainly in the arms, led, in most patients, to an initial diagnosis of motor neuron disease. In some patients (nine of 24), there was no appreciable muscle atrophy. Tendon reflexes were often absent or weak. The finding of persistent multifocal conduction block confined to motor nerve fibres raises questions about the nature and the importance of this syndrome. Segmental reduction of motor conduction velocity occurred at the site of the block, but significant slowing of motor nerve conduction was not found outside this site. The response to intravenous IVIg treatment seems to be correlated with the absence of amyotrophy. Patients with little or no amyotrophy had an initial and sustained response to IVIg, and did not develop amyotrophy during the follow up study. They could be considered to have a variant of chronic inflammatory demyelinating polyneuropathy. Patients with pronounced amyotrophy independent of the disease duration did not respond as well to IVIg treatment, suggesting the existence of a distinct entity. Among the patients treated about two thirds who had an initial good response to IVIg had high or significant antiganglioside GM1 (anti-GM1) antibody titres, but there was no correlation between the high titres before treatment and long lasting response to IVIg treatment. Images PMID:7608707

  2. Study of single-nucleotide polymorphisms by means of electrical conductance measurements

    PubMed Central

    Hihath, Joshua; Xu, Bingqian; Zhang, Peiming; Tao, Nongjian

    2005-01-01

    Understanding the complexities of DNA has been a hallmark of science for over a half century, and one of the important topics in DNA research is recognizing the occurrence of mutations in the base-stack. In this article, we present a study of SNPs by direct-contact electrical measurements to a single DNA duplex. We have used short, 11- and 12-bp dsDNA to investigate the change in conductance that occurs if a single base pair, a single base, or two separate bases in the stack are modified. All measurements are carried out in aqueous solution with the DNA chemically bound to the electrodes. These measurements demonstrate that the presence of a single base pair mismatch can be identified by the conductance of the molecule and can cause a change in the conductance of dsDNA by as much as an order of magnitude, depending on the specific details of the double helix and the single nucleotide polymorphism. PMID:16284253

  3. Computational Study of Subdural Cortical Stimulation: Effects of Simulating Anisotropic Conductivity on Activation of Cortical Neurons

    PubMed Central

    Seo, Hyeon; Kim, Donghyeon; Jun, Sung Chan

    2015-01-01

    Subdural cortical stimulation (SuCS) is an appealing method in the treatment of neurological disorders, and computational modeling studies of SuCS have been applied to determine the optimal design for electrotherapy. To achieve a better understanding of computational modeling on the stimulation effects of SuCS, the influence of anisotropic white matter conductivity on the activation of cortical neurons was investigated in a realistic head model. In this paper, we constructed pyramidal neuronal models (layers 3 and 5) that showed primary excitation of the corticospinal tract, and an anatomically realistic head model reflecting complex brain geometry. The anisotropic information was acquired from diffusion tensor magnetic resonance imaging (DT-MRI) and then applied to the white matter at various ratios of anisotropic conductivity. First, we compared the isotropic and anisotropic models; compared to the isotropic model, the anisotropic model showed that neurons were activated in the deeper bank during cathodal stimulation and in the wider crown during anodal stimulation. Second, several popular anisotropic principles were adapted to investigate the effects of variations in anisotropic information. We observed that excitation thresholds varied with anisotropic principles, especially with anodal stimulation. Overall, incorporating anisotropic conductivity into the anatomically realistic head model is critical for accurate estimation of neuronal responses; however, caution should be used in the selection of anisotropic information. PMID:26057524

  4. Role Modeling in the First 2 Years of Medical School.

    PubMed

    Obadia, Sharon J

    2015-08-01

    Role modeling opportunities for osteopathic physician teachers during a student's first 2 years of medical school are emerging as more colleges of osteopathic medicine strive to connect basic science didactics with clinically based learning activities. Examples of positive modeling by physician teachers during the first years of medical school are illustrated by 10 vignettes that can be incorporated into faculty development programs to increase awareness of such opportunities. The physician teacher in each vignette interacts with the student demonstrating desired professional behaviors. These vignettes also illustrate the effect of a positive "hidden curriculum" on a student's professional development. By recognizing these valuable teachable moments, teachers can incorporate role modeling into their daily practice. PMID:26214824

  5. A phonological system at 2 years after cochlear implantation

    PubMed Central

    CHIN, STEVEN B.; PISONI, DAVID B.

    2011-01-01

    This report is a description of a developing phonological system as manifested in the productions of a prelingually deafened child approximately 2 years after fitting with a Nucleus 22-Channel Multi-Electrode Cochlear Implant. A probe list consisting of 23 proper nouns familiar to the child was used to elicit samples of her speech; stimulus materials consisted of photographs of those persons (friends and family members) whose names were included in the probe list. Analysis of the child's productions addressed the composition of the phonetic inventory of consonants and vowels and the presence of syllable structure and other phonotactic constraints. Results indicated a rich inventory of speech sound segments (among both consonants and vowels) and a lack of stringent constraints on syllable structure and consonants permitted in specified word positions. A further comparative analysis of correspondences with the ambient language showed a number of patterns that are also common in the speech of children with normal hearing. PMID:22091697

  6. Electrokinetic experimental study on saturated rock samples: zeta potential and surface conductance

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Hu, Hengshan; Guan, Wei; Li, Hui

    2015-05-01

    It is important to know the electrokinetic properties of crustal rocks for interpreting the conductivity mechanisms and seismoelectric phenomena during earthquakes and seismoelectric well logging. In this study, electrokinetic experiments are conducted using a special core-holder by employing an AC lock-in technique. A series of experiments are conducted on 10 sandstone samples to measure the streaming potentials and streaming currents, and the experiments on each sample are done at six different salinities. The streaming potential coefficient and streaming current coefficient are calculated from the measured streaming potentials and streaming currents. The experimental results show that streaming potential coefficient and streaming current coefficient decrease as the salinity increases. The dependence of these two coefficients on permeability and pore radius are analysed and compared with previous works. At low salinities, the streaming potential coefficient and streaming current coefficient increase with the increasing permeability and pore radius. At high salinities, the streaming potential coefficient (streaming current coefficient) almost share a same value for 10 different samples. This conclusion indicates that the differences of rock parameters can only be well recognized at lower salinities, and the electrokinetic signals are invalid at high salinities, which offers a restrictive condition for using the amplitude of electrokinetic signals to estimate rock parameters. The zeta-potential have also been estimated through combined measurements of streaming potential and streaming current. The surface conductivity and its contribution to electrokinetic effects are determined from a comparison of zeta-potentials by two different methods, and then the validation of the Helmholz-Smoluchowski equation for a capillary tube is tested in rocks. We also compare our date with theoretical and experimental works, and set up an expression about the relationship between

  7. Thermal conductivity studies of novel nanofluids based on metallic silver decorated mesoporous silica nanoparticles

    SciTech Connect

    Tadjarodi, Azadeh; Zabihi, Fatemeh

    2013-10-15

    Graphical abstract: - Highlights: • Metallic silver was decorated in mSiO{sub 2} with grafted hemiaminal functional groups. • Synthesized nanoparticles were used for preparation of glycerol based nanofluids. • The effect of temperature, weight fraction of mSiO{sub 2} and concentration of silver nanoparticles on thermal conductivity of nanofluids was investigated. - Abstract: In the present study, the mesoporous structure of silica (mSiO{sub 2}) nanoparticles as well as hemiaminal grafted mSiO{sub 2} decorated by metallic silver (Ag/mSiO{sub 2}) has been used for the preparation of glycerol based nanofluids. Structural and morphological characterization of the synthesized products have been carried out using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD), UV–vis spectroscopy, inductively coupled plasma (ICP) and N{sub 2} adsorption–desorption isotherms. The thermal conductivity and viscosity of the nanofluids have been measured as a function of temperature for various weight fractions and silver concentrations of mSiO{sub 2} and Ag/mSiO{sub 2} nanoparticles, respectively. The results show that the thermal conductivity of the nanofluids increase up to 9.24% as the weight fraction of mSiO{sub 2} increases up to 4 wt%. Also, increasing the percent of the silver decorated mSiO{sub 2} (Ag/mSiO{sub 2}) up to 2.98% caused an enhancement in the thermal conductivity of the base fluid up to 10.95%. Furthermore, the results show that the nanofluids have Newtonian behavior in the tested temperature range for various concentrations of nanoparticles.

  8. Oxygen flux and dielectric response study of Mixed Ionic-Electronic Conducting (MIEC) heterogeneous functional materials

    NASA Astrophysics Data System (ADS)

    Rabbi, Fazle

    Dense mixed ionic-electronic conducting (MIEC) membranes consisting of ionic conductive perovskite-type and/or fluorite-type oxides and high electronic conductive spinel type oxides, at elevated temperature can play a useful role in a number of energy conversion related systems including the solid oxide fuel cell (SOFC), oxygen separation and permeation membranes, partial oxidization membrane reactors for natural gas processing, high temperature electrolysis cells, and others. This study will investigate the impact of different heterogeneous characteristics of dual phase ionic and electronic conductive oxygen separation membranes on their transport mechanisms, in an attempt to develop a foundation for the rational design of such membranes. The dielectric behavior of a material can be an indicator for MIEC performance and can be incorporated into computational models of MIEC membranes in order to optimize the composition, microstructure, and ultimately predict long term membrane performance. The dielectric behavior of the MIECs can also be an indicator of the transport mechanisms and the parameters they are dependent upon. For this study we chose a dual phase MIEC oxygen separation membrane consisting of an ionic conducting phase: gadolinium doped ceria-Ce0.8 Gd0.2O2 (GDC) and an electronic conductive phase: cobalt ferrite-CoFe2O4 (CFO). The membranes were fabricated from mixtures of Nano-powder of each of the phases for different volume percentages, sintered with various temperatures and sintering time to form systematic micro-structural variations, and characterized by structural analysis (XRD), and micro-structural analysis (SEM-EDS). Performance of the membranes was tested for variable partial pressures of oxygen across the membrane at temperatures from 850°C-1060°C using a Gas Chromatography (GC) system. Permeated oxygen did not directly correlate with change in percent mixture. An intermediate mixture 60%GDC-40%CFO had the highest flux compared to the 50%GDC

  9. A study of conductive hydrogel composites of pH-responsive microgels and carbon nanotubes.

    PubMed

    Cui, Zhengxing; Zhou, Mi; Greensmith, Paula J; Wang, Wenkai; Hoyland, Judith A; Kinloch, Ian A; Freemont, Tony; Saunders, Brian R

    2016-05-14

    Conductive gel composites are attracting considerable attention because of their interesting electrical and mechanical properties. Here, we report conductive gel composites constructed using only colloidal particles as building blocks. The composites were prepared from mixed dispersions of vinyl-functionalised pH-responsive microgel particles (MGs) and multi-walled carbon nanotubes (CNTs). MGs are crosslinked pH-responsive polymer colloid particles that swell when the pH approaches the pKa of the particles. Two MG systems were used which contained ethyl acrylate (EA) or methyl acrylate (MA) and around 30 mol% of methacrylic acid (MAA). The MA-based MG is a new pH-responsive system. The mixed MG/CNT dispersions formed thixotropic physical gels. Those gels were transformed into covalent interlinked electrically conducting doubly crosslinked microgel/CNT composites (DX MG/CNT) by free-radical reaction. The MGs provided the dual roles of dispersant for the CNTs and macro-crosslinker for the composite. TEM data showed evidence for strong attraction between the MG and the CNTs which facilitated CNT dispersion. An SEM study confirmed CNT dispersion throughout the composites. The mechanical properties of the composites were studied using dynamic rheology and uniaxial compression measurements. Surprisingly, both the ductility and the modulus of the gel composites increased with increasing CNT concentration used for their preparation. Human adipose-derived mesenchymal stem cells (AD-MSCs) exposed to DX MG/CNT maintained over 99% viability with metabolic activity retained over 7 days, which indicated non-cytotoxicity. The results of this study suggest that our approach could be used to prepare other DX MG/CNT gel composites and that these materials may lead to future injectable gels for advanced soft-tissue repair. PMID:27067636

  10. Prospective multicenter assessment of perioperative and minimum 2-year postoperative complication rates associated with adult spinal deformity surgery.

    PubMed

    Smith, Justin S; Klineberg, Eric; Lafage, Virginie; Shaffrey, Christopher I; Schwab, Frank; Lafage, Renaud; Hostin, Richard; Mundis, Gregory M; Errico, Thomas J; Kim, Han Jo; Protopsaltis, Themistocles S; Hamilton, D Kojo; Scheer, Justin K; Soroceanu, Alex; Kelly, Michael P; Line, Breton; Gupta, Munish; Deviren, Vedat; Hart, Robert; Burton, Douglas C; Bess, Shay; Ames, Christopher P

    2016-07-01

    OBJECTIVE Although multiple reports have documented significant benefit from surgical treatment of adult spinal deformity (ASD), these procedures can have high complication rates. Previously reported complications rates associated with ASD surgery are limited by retrospective design, single-surgeon or single-center cohorts, lack of rigorous data on complications, and/or limited follow-up. Accurate definition of complications associated with ASD surgery is important and may serve as a resource for patient counseling and efforts to improve the safety of patient care. The authors conducted a study to prospectively assess the rates of complications associated with ASD surgery with a minimum 2-year follow-up based on a multicenter study design that incorporated standardized data-collection forms, on-site study coordinators, and regular auditing of data to help ensure complete and accurate reporting of complications. In addition, they report age stratification of complication rates and provide a general assessment of factors that may be associated with the occurrence of complications. METHODS As part of a prospective, multicenter ASD database, standardized forms were used to collect data on surgery-related complications. On-site coordinators and central auditing helped ensure complete capture of complication data. Inclusion criteria were age older than 18 years, ASD, and plan for operative treatment. Complications were classified as perioperative (within 6 weeks of surgery) or delayed (between 6 weeks after surgery and time of last follow-up), and as minor or major. The primary focus for analyses was on patients who reached a minimum follow-up of 2 years. RESULTS Of 346 patients who met the inclusion criteria, 291 (84%) had a minimum 2-year follow-up (mean 2.1 years); their mean age was 56.2 years. The vast majority (99%) had treatment including a posterior procedure, 25% had an anterior procedure, and 19% had a 3-column osteotomy. At least 1 revision was required in 82

  11. Studying the conductance and transport in low-dimensional graphene nano ribbon under ballistic regime

    NASA Astrophysics Data System (ADS)

    Pratap, Surender; Sarkar, Niladri

    2016-05-01

    NEGF procedure has been discussed in detail to study the conductance in Graphene Nano-Ribbons (GNR). The discretization procedure for the GNRs and CNTs for zig-zag configurations has been discussed in detail. We have explained this with a block diagram where each block represents a block diagonal matrix. We have used tight-binding procedure to obtain the block diagonal matrices for GNRs. We have applied a recursive method to obtain the Green's function for GNR based channels. Also a self consistent procedure is shown here which can be used to calculate the I-V characteristic of a GNR based Nano-scale devices.

  12. Numerical study of 1-D, 3-vector component, thermally-conductive MHD solar wind

    NASA Technical Reports Server (NTRS)

    Han, S.; Wu, S. T.; Dryer, M.

    1993-01-01

    In the present study, transient, 1-dimensional, 3-vector component MHD equations are used to simulate steady and unsteady, thermally conductive MHD solar wind expansions between the solar surface and 1 AU (astronomical unit). A variant of SIMPLE numerical method was used to integrate the equations. Steady state solar wind properties exhibit qualitatively similar behavior with the known Weber-Davies Solutions. Generation of Alfven shock, in addition to the slow and fast MHD shocks, was attempted by the boundary perturbations at the solar surface. Property changes through the disturbance were positively correlated with the fast and slow MHD shocks. Alfven shock was, however, not present in the present simulations.

  13. Yusho and its latest findings-A review in studies conducted by the Yusho Group.

    PubMed

    Mitoma, Chikage; Uchi, Hiroshi; Tsukimori, Kiyomi; Yamada, Hideyuki; Akahane, Manabu; Imamura, Tomoaki; Utani, Atsushi; Furue, Masutaka

    2015-09-01

    The Yusho incident is an unprecedented mass food poisoning that occurred in Japan in 1968. It was caused by the ingestion of rice bran oil contaminated with polychlorinated biphenyls (PCBs) and various dioxins and dioxin-like compounds, such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The victims of Yusho have suffered from characteristic skin manifestations associated with systemic, ophthalmological, and mucosal symptoms for a long period of time. The Study Group of Yusho (the Yusho Group) has been conducting annual medical check-ups on Yusho victims for more than 45years. Since 2002, when concentrations of dioxins in the blood of Yusho patients started to be measured, the pharmacokinetics of dioxins, relationship between blood levels of dioxins and symptoms/signs in patients directly exposed to dioxins, and the adverse effects on the next generation have become dramatically clear. Herein we review recent findings of studies conducted by the Yusho Group to evaluate chronic dioxin-induced toxicity to the next generation as well as Yusho patients in comparison with a similar food mass poisoning, the Yucheng incident. Additionally, we summarized basic studies carried out by the Yusho Group to re-evaluate the mechanisms of dioxin toxicities in experimental models and various functions of the aryl hydrocarbon receptor (AhR), known as the dioxin receptor, pathway. PMID:26010306

  14. Conducting systematic reviews of intervention questions III: Synthesizing data from intervention studies using meta-analysis.

    PubMed

    O'Connor, A M; Sargeant, J M; Wang, C

    2014-06-01

    This article is the sixth in a series of six articles describing systematic reviews of interventions in animal agriculture and veterinary medicine. The first article provided an overview of systematic reviews, followed by an article on building evidence across study designs, and an article describing criteria for validity in randomized controlled trials. The fourth article in this series overviewed the initial steps in conducting a systematic review: development of a review protocol, identification of the structured question to be addressed and conducting a comprehensive literature search to identify potentially relevant research to address the review question. The fifth article introduced relevance screening of literature to identify and include research that is relevant to the review question, the use of standardized checklists and procedures to assess the risk of bias in the relevant research, data extraction from primary research studies and summarizing the results of the body of research identified. Many systematic reviews of interventions aim to use a quantitative method to combine the results of multiple studies and provide a more precise estimate of the effect of the intervention on the outcome, that is, a summary effect measure. The objective of this article was to describe general approaches that are available for quantitative synthesis of data. Specific details of all meta-analysis statistical approaches are beyond the capacity of this article. PMID:24905996

  15. Myopia Control with a Novel Peripheral Gradient Soft Lens and Orthokeratology: A 2-Year Clinical Trial

    PubMed Central

    Pauné, Jaime; Morales, Hari; Armengol, Jesús; Quevedo, Lluisa; Faria-Ribeiro, Miguel; González-Méijome, José M.

    2015-01-01

    Objective. To evaluate the degree of axial elongation with soft radial refractive gradient (SRRG) contact lenses, orthokeratology (OK), and single vision (SV) spectacle lenses (control) during a period of 1 year before treatment and 2 years after treatment. Methods. This was a prospective, longitudinal, nonrandomized study. The study groups consisted of 30, 29, and 41 children, respectively. The axial length (AL) was measured during 2 years after recruitment and lens fitting. Results. The baseline refractive sphere was correlated significantly (Spearman's Rho (ρ) correlation = 0.542; P < 0.0001) with the amount of myopia progression before baseline. After 2 years, the mean myopia progression values for the SRRG, OK, and SV groups were −0.56 ± 0.51, −0.32 ± 0.53, and −0.98 ± 0.58 diopter, respectively. The results represent reductions in myopic progression of 43% and 67% for the SRRG and OK groups, respectively, compared to the SV group. The AL increased 27% and 38% less in the SRRG and OK groups, respectively compared with the SV group at the 2-year visit (P < 0.05). Axial elongation was not significantly different between SRRG and OK (P = 0.430). Conclusion. The SRRG lens significantly decreased AL elongation compared to the SV control group. The SRRG lens was similarly effective to OK in preventing myopia progression in myopic children and adolescent. PMID:26605331

  16. It's all about relationships: A qualitative study of health researchers' perspectives of conducting interdisciplinary health research

    PubMed Central

    Nair, Kalpana M; Dolovich, Lisa; Brazil, Kevin; Raina, Parminder

    2008-01-01

    Background Interdisciplinary research has been promoted as an optimal research paradigm in the health sciences, yet little is known about how researchers experience interdisciplinarity in practice. This study sought to determine how interdisciplinary research was conceptualized and operationalized from the researcher's perspective and to better understand how best to facilitate interdisciplinary research success. Methods Key informant interviews were conducted with health researchers with expertise or experience in conducting interdisciplinary research. Interviews were completed either in person or over the telephone using a semi-structured interview guide. Data collection occurred simultaneously with data analysis so that emerging themes could be explored in subsequent interviews. A content analysis approach was used. Results Nineteen researchers took part in this study. Interdisciplinary research was conceptualized disparately between participants, and there was modest attention towards operationalization of interdisciplinary research. There was one overriding theme, "It's all about relationships", that emerged from the data. Within this theme, there were four related subthemes: 1) Involvement in interdisciplinary research; 2) Why do I do interdisciplinary research?; 3) Managing and fostering interdisciplinary relationships; and 4) The prickly side to interdisciplinary research. Together, these themes suggest that the choice to conduct interdisciplinary research, though often driven by the research question, is highly influenced by interpersonal and relationship-related factors. In addition, researchers preferred to engage in interdisciplinary research with those that they had already established relationships and where their role in the research process was clearly articulated. A focus on relationship building was seen as a strong facilitator of interdisciplinary success. Conclusion Many health researchers experienced mixed reactions towards their involvement in

  17. Increased Food Insecurity Among Mothers of 2 Year Olds with Special Health Care Needs.

    PubMed

    Adams, Elizabeth J; Hoffmann, Laurel M; Rosenberg, Kenneth D; Peters, Dawn; Pennise, Melissa

    2015-10-01

    The objective of this study is to explore the association between having a child with special health care needs (CSHCN) and food insecurity when the child is 2 years old. We studied women who had a live birth in 2004-2005 and responded to Oregon's Pregnancy Risk Assessment Monitoring System (PRAMS) survey 3 months postpartum (Time 1) and the follow-up survey (PRAMS-2), when the child was 2 years old (Time 2). Women answering affirmatively to the PRAMS-2 question, "In the last 12 months, did you ever eat less than you felt you should because there was not enough money for food?" were considered food insecure. CSHCN status was identified by affirmative responses to questions about needs for ongoing services (Time 2). PRAMS and PRAMS-2 responses were weighted for study design and non-response. Results report weighted analyses, unless noted. Among 1812 mothers completing PRAMS-2, 13.6 % (unweighted) had a 2-year-old CSHCN and 11.9 % (unweighted) were food insecure at Time 2. The estimated prevalence of food insecurity at 2-year follow-up was 20.7 % among families of CSHCN and 9.7 % for others. After adjustment for Time 2 marital status, education, lifetime U.S. residence, income and health conditions, multivariable logistic regression revealed that odds of food insecurity were more than two times as great for CSHCN mothers 2 years post-partum compared to non-CSHCN mothers (adjusted odds ratio 2.6, 95 % confidence interval 1.3, 4.6). Families of CSHCN face increased risk for food insecurity. Improved understanding of causal determinants of food insecurity among households of CSHCN is needed. PMID:25682114

  18. Environmental NO2 Level is Associated with 2-Year Mortality in Patients Undergoing Peritoneal Dialysis

    PubMed Central

    Lin, Jui-Hsiang; Yen, Tzung-Hai; Weng, Cheng-Hao; Huang, Wen-Hung

    2015-01-01

    Abstract An ongoing issue related to global urbanization is the association of air pollution with increased incidences of morbidity and mortality. However, no in-depth study has investigated this issue focusing on peritoneal dialysis (PD) patients. Therefore, this study assessed the effects of traffic-related air pollutants and other important mortality-associated factors on 2-year mortality in PD patients. A total of 160 PD patients were recruited in this 2-year retrospective observational study. Differences in air quality were analyzed with respect to the patients’ living areas. The PD patients were categorized into 2 groups according to high (n = 65) and low (n = 95) nitrogen dioxide (NO2) exposure. Demographic, hematological, nutritional, inflammatory, biochemical, air pollutants, and dialysis-related data were analyzed. Univariate and multivariate Cox regression analyses were used for 2-year mortality analysis. A total of 160 PD patients (38 men and 122 women) were enrolled. Fourteen patients (8.8%) died within 2 years; among them, the causes of death were infection (n = 10), malignancy (n = 1), and cardiovascular events (n = 3). Among the 10 patients who died from infection, 5, 4, and 1 died from pneumonia, PD-related peritonitis, and sepsis of unknown origin, respectively. All patients who died from pneumonia were living in high environmental NO2 exposure areas. Multivariate Cox regression analysis showed that age (hazard ratio [HR] 1.073, 95% confidence interval [CI] [1.013–1.137]; P = 0.017), white blood cell count (HR 1.41, 95% CI [1.116–1.781]; P = 0.004), log normalized protein nitrogen appearance (HR 0.0001, 95% CI [0–0.073]; P = 0.005), high cardiothoracic ratio (HR 14.28, 95% CI [1.778–114.706]; P = 0.012), and high environmental NO2 exposure (HR 3.776, 95% CI [1.143–12.47]; P = 0.029) were significantly associated with 2-year mortality. PD patients with high environmental NO2 exposure had a higher

  19. Environmental NO2 level is associated with 2-year mortality in patients undergoing peritoneal dialysis.

    PubMed

    Lin, Jui-Hsiang; Yen, Tzung-Hai; Weng, Cheng-Hao; Huang, Wen-Hung

    2015-01-01

    An ongoing issue related to global urbanization is the association of air pollution with increased incidences of morbidity and mortality. However, no in-depth study has investigated this issue focusing on peritoneal dialysis (PD) patients. Therefore, this study assessed the effects of traffic-related air pollutants and other important mortality-associated factors on 2-year mortality in PD patients.A total of 160 PD patients were recruited in this 2-year retrospective observational study. Differences in air quality were analyzed with respect to the patients' living areas. The PD patients were categorized into 2 groups according to high (n = 65) and low (n = 95) nitrogen dioxide (NO2) exposure. Demographic, hematological, nutritional, inflammatory, biochemical, air pollutants, and dialysis-related data were analyzed. Univariate and multivariate Cox regression analyses were used for 2-year mortality analysis.A total of 160 PD patients (38 men and 122 women) were enrolled. Fourteen patients (8.8%) died within 2 years; among them, the causes of death were infection (n = 10), malignancy (n = 1), and cardiovascular events (n = 3). Among the 10 patients who died from infection, 5, 4, and 1 died from pneumonia, PD-related peritonitis, and sepsis of unknown origin, respectively. All patients who died from pneumonia were living in high environmental NO2 exposure areas. Multivariate Cox regression analysis showed that age (hazard ratio [HR] 1.073, 95% confidence interval [CI] [1.013-1.137]; P = 0.017), white blood cell count (HR 1.41, 95% CI [1.116-1.781]; P = 0.004), log normalized protein nitrogen appearance (HR 0.0001, 95% CI [0-0.073]; P = 0.005), high cardiothoracic ratio (HR 14.28, 95% CI [1.778-114.706]; P = 0.012), and high environmental NO2 exposure (HR 3.776, 95% CI [1.143-12.47]; P = 0.029) were significantly associated with 2-year mortality.PD patients with high environmental NO2 exposure had a higher 2-year mortality rate

  20. Serial nerve conduction studies in vitamin B12 deficiency-associated polyneuropathy.

    PubMed

    Huang, Chi-Ren; Chang, Wen-Neng; Tsai, Nai-Wen; Lu, Cheng-Hsien

    2011-02-01

    This report is on a 22-year-old male vegetarian with acute polyneuropathy secondary to vitamin B(12) deficiency. He presented with weakness and numbness of the distal limbs and absent deep tendon reflex in all four extremities. Nerve conduction study (NCS) showed an axonal type sensori-motor polyneuropathy. Serum biochemical studies revealed vitamin B(12) level of 119 pg/mL (reference range 185-710 pg/mL), with elevated creatine kinase (CK) (719 U/L) and homocysteine (Hcy) (24.04 μmol/L) levels. Anti-parietal cell antibody test was positive. The patient received both oral and intramuscular injection of vitamin B(12). The amplitude of the median and ulnar motor NCS increased 2.5 months later, while muscle power of the ankle plantar flexion and dorsiflexion recovered after 3.5 and 5.5 months, respectively. Follow-up NCS after 14.5 months showed response in sural NCS, but not the peroneal NCS. Follow-up also showed decreased serum Hcy and CK to 9.6 μmol/L and 198 U/L, respectively, and increasing amplitude of response. Recovery sequence involved muscle power of the proximal muscles, hands, plantar flexion, and dorsiflexion of the feet, and followed by sensory conduction. PMID:20890625

  1. Probing the role of Ga in amorphous conducting oxides through local structure studies

    NASA Astrophysics Data System (ADS)

    Moffitt, Stephanie; Zhu, Qimin; Ma, Qing; Buchholz, Donald; Chang, Robert; Mason, Thomas; Marks, Tobin; Bedzyk, Michael

    2015-03-01

    The study of amorphous (a-) conducting oxides is an emerging field. The lack of grain boundaries, smooth surfaces, and low temperature deposition position these materials as ideal candidates for large area applications and flexible electronics. Most impressively, these materials maintain high electron mobility in the amorphous state. These benefits have led the recent commercialization of a-IGZO (Ga and Zn doped indium oxide) as a replacement for a-Si as the channel layer of thin film transistors in display technology. Despite this success, fundamental understanding of structure-property relationships is still lacking and must be improved to guide further development of amorphous conducting oxides. X-ray absorption spectroscopy (XAS) is one of the few tools that can be used to probe the structure of amorphous materials. Amorphous indium oxide doped with Ga (a-IGO) is a model system to help develop the role of dopants in amorphous oxides. An in depth XAS study was carried out to determine inter-atomic distances, coordination numbers, and structural disorder parameters as a function of Ga doping level. The correlation between XAS-derived structural features and the dopant-dependent evolution of both electrical properties and thermal stability of a-IGO will be discussed. This work is supported by the NSF MRSEC Program No. DMR1121262.

  2. Nitrogen-doped ZnO shells: Studies on optical transparency and electrical conductivity

    SciTech Connect

    Gaikwad, Rajendra S.; Mane, Rajaram S.; Pawar, Bhagwat N.; Ambade, Rohan B.; Ahn, Hee Joon; Han, Sung-Hwan; Joo, Oh-Shim

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Chemical spray growth of high quality zinc oxide nitrogen-doped films is explored. Black-Right-Pointing-Pointer Effect of nitrogen doping on crystallinity, surface morphology, and optical properties is comprehensively studied. Black-Right-Pointing-Pointer ZnO structural properties are optimized. Black-Right-Pointing-Pointer Effect of nitrogen doping on a gas sensing application of ZnO is investigated. -- Abstract: Studies on optical and electrical conductivity in nitrogen (N)-doped ZnO shells are explored. On incorporating low levels of nitrogen, the (0 0 2) X-ray diffraction (XRD) peak was found to be intensified significantly. Closely packed spherical crystallites of ZnO were transformed into flat-flakes during 0.1-0.3 M nitrogen doping and finally to shells, flattered at the center and tapered at ends, at 0.4 M. Both pristine and N-doped ZnO films show hydrophilic character. It was also found that the degree of transparency and the nature of conductivity as estimated by optical absorbance and Hall measurement, respectively, were strongly influenced by the levels of N-doping. Higher nitrogen doping led to decline in electrical resistivity and mobility due to an enhancement of free charge carriers. Presence of both (N{sub 2}){sub O} donor and (N){sub O} acceptor peaks in X-ray photoelectron spectroscopy could be responsible for the formation of higher carrier concentration in ZnO films.

  3. Effects of vacancy defects on thermal conductivity in crystalline silicon: A nonequilibrium molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Lee, Yongjin; Lee, Sangheon; Hwang, Gyeong S.

    2011-03-01

    We examine the effects of vacancy defects on thermal conductivity in bulk crystalline silicon (c-Si) using nonequilibrium molecular dynamics simulations. While most vacancies are thought to remain in the form of clusters in bulk c-Si, recent theoretical studies have predicted that small vacancy clusters energetically prefer to be fourfold coordinated by nullifying dangling bonds. Hence, in this work, we consider three different-sized fourfold vacancy clusters, tetra- (V4), hexa- (V6), and dodeca-vacancy (V12), with particular interest in studying how phonon transport is affected by vacancy concentration and cluster size in association with fourfold coordination-induced lattice distortions. Our simulations show that thermal conductivity (κ) rapidly drops with vacancy concentration (nv) with an inverse power-law relation (κ∝nv-α, with α ≈ 0.7-1.1 depending on cluster size); the presence of 1.5% vacancies leads to a 95% reduction in κ as compared to the defect free c-Si. When nv is low (<1%), the reduction of κ with nv appears to be a function of cluster size, and the size effect becomes unimportant as nv increases above 1%. We discuss the correlation between phone scattering and cluster size, based on the relative rates of phonon-vacancy scattering associated with defect-induced strain fields. We also estimate the dependence of phonon mean free path on vacancy concentration and cluster size.

  4. Nerve conduction studies, skeletal muscle EMG, and sphincter EMG in multiple system atrophy.

    PubMed Central

    Pramstaller, P P; Wenning, G K; Smith, S J; Beck, R O; Quinn, N P; Fowler, C J

    1995-01-01

    Although autonomic failure, parkinsonism, and cerebellar and pyramidal signs are well documented in multiple system atrophy, much less is known about the frequency and severity of involvement of the peripheral nervous system. The frequency and nature of peripheral nerve involvement has therefore been determined in 74 patients with multiple system atrophy using nerve conduction studies and skeletal muscle EMG. These findings were compared with those on sphincter EMG. Ninety per cent of the patients had an abnormal sphincter EMG, indicating denervation and reinnervation consistent with anterior horn cell loss in Onuf's nucleus, but only 40% had either abnormal nerve conduction studies (mixed sensorimotor axonal neuropathy in 17.5%) or abnormal skeletal muscle EMG (suggesting partial denervation in 22.5%). These data indicate a remarkable selective vulnerability of the anterior horn cells of Onuf's nucleus innervating external sphincter muscles relative to those supplying skeletal muscle in patients with multiple system atrophy. If this selective pattern of involvement can be explained it may be a clue to pathogenetic mechanisms in multiple system atrophy. PMID:7745413

  5. Low conductivity water loop heat pump study at Lawrence Livermore National Laboratory

    SciTech Connect

    Chen, C.C.; Onu, C.; Smith, T.; Holda, M.

    1995-12-31

    Based on results of the new Water Source Heat Pump (WSHP) systems operating in the US, these highly efficient heat pumps provide energy saving that will make them economically feasible to replace the inefficient, conventional HVAC systems. Additionally, an option to replace a centrifugal-compressor CFC chiller with a non-CFC chiller can be to replace the system with a highly efficient Water-Loop Heat Pump (WSHP) system. This replacement can result in a reduction of 20 to 30% in heating and air-conditioning energy costs. Low Conductivity Water (LCW) is purified water used for cooling in experimental laboratory, process, and air-conditioning equipment. It is one of several lab-wide mechanical utilities systems provided at Lawrence Livermore National Laboratory (LNL). The system is designed to maintain a supply temperature between 65 F and 85 F, with 100 psi at the inlet of the user building, 50--55 psi minimum differential pressures in the building, 35 psi maximum return pressure, and 0.4 umho/cm conductivity. However, this study is to utilize the existing LCW water loop to achieve the energy-efficiency improvement in a water resource heat pump (WRHP) system. The study will also utilize the life cycle costs as a tool to as the general selected criteria.

  6. [Physiological approach to peripheral neuropathy. Conventional nerve conduction studies and magnetic motor root stimulation].

    PubMed

    Ugawa, Yoshikazu

    2004-11-01

    In this communication, I first show some points we should mind in the conventional peripheral nerve conduction studies and later present clinical usefulness of motor root stimulation for peripheral neuropathy. CONVENTIONAL NERVE CONDUCTION STUDIES (NCS): The most important point revealed by the conventional NCSs is whether neuropathy is due to axonal degeneration or demyelinating process. Precise clinical examination with this neurophysiological information leads us to a diagnosis and treatment. Poor clinical examination makes these findings useless. Long standing axonal degeneration sometimes induces secondary demyelination at the most distal part of involved nerves. On the other hand, severe segmental demyelination often provokes secondary axonal degeneration at distal parts to the site of demyelination. These secondary changes show the same abnormal neurophysiological findings as those of the primary involvement. We should be careful of this possibility when interpreting the results of NCS. NCS of sensory nerves is not good at revealing demyelinating process. Mild temporal dispersion of potentials often reduces an amplitude of SNAP or loss of responses, which usually suggests axonal degeneration, because of short duration of sensory nerve potentials. MOTOR ROOT STIMULATION IN PERIPHERAL NEUROPATHY: Magnetic stimulation with a coil placed over the spine activates motor roots and evokes EMG responses from upper and lower limb muscles. The site of activation with this method was determined to be where the motor roots exit from the spinal canal (intervertebral foramina) (J Neurol Neurosurg Psychiatry 52 (9): 1025-1032, 1989) because induced currents are very dense at such a foramen made by electric resistant bones. In several kinds of peripheral neuropathy, this method has been used to detect a lesion at a proximal part of the peripheral nerves which can not be detected by the conventional NCSs. I present a few cases in whom motor root stimulation had a clinical

  7. Safety of nerve conduction studies in patients with implanted cardiac devices.

    PubMed

    Schoeck, Andreas P; Mellion, Michelle L; Gilchrist, James M; Christian, Fredric V

    2007-04-01

    Patients with implanted cardiac devices and their physicians may defer important electrodiagnostic testing because of anxiety about potential negative effects on the device. To determine the safety of routine nerve conduction studies (NCS) in this population, 10 patients with permanent dual-chamber pacemakers of various types and five patients with implanted cardiac defibrillators (ICD) underwent nerve stimulation at sites commonly used during NCS. The implanted cardiac device was interrogated before and after the study and there was continuous monitoring of the surface electrocardiogram (ECG) and atrial and ventricular electrograms. Electrical impulses generated during routine NCS were never detected by the sensing amplifier and did not affect the programmed settings of the implanted cardiac device. We conclude that routine NCS is safe in patients with implanted cardiac pacemakers with bipolar sensing configurations and defibrillators. PMID:17094099

  8. Behavioral trends in young children with conductive hearing loss: a case-control study.

    PubMed

    Gouma, Panagiota; Mallis, Antonios; Daniilidis, Vasilis; Gouveris, Haralambos; Armenakis, Nikolaos; Naxakis, Stephanos

    2011-01-01

    Otitis media with effusion (OME) is a common condition affecting children and a well-known cause of conductive hearing loss that can potentially lead to speech development disorders. Recent studies, however, have demonstrated the influence of OME on development of attention disorders or social adaptation and acceptance. Hence, this study aimed to investigate the behavioral trends of children with OME based on the Achenbach test. A group of 117 patients with episodes of OME at the age of 4-5 was compared with a control group according to the Achenbach system of evaluation, by application of the Child Behavior Checklist questionnaire (CBCL). Patients suffering from OME had more anxiety/depression related disorders and attention disorders as compared with the control group. The psychological effect of OME in children of ages 6-8 is evident with anxiety and depression disorders being especially prominent among these patients. PMID:20665042

  9. Characterizing diverse orthologues of the cystic fibrosis transmembrane conductance regulator protein for structural studies.

    PubMed

    Pollock, Naomi L; Rimington, Tracy L; Ford, Robert C

    2015-10-01

    As an ion channel, the cystic fibrosis transmembrane conductance regulator (CFTR) protein occupies a unique niche within the ABC family. Orthologues of CFTR are extant throughout the animal kingdom from sharks to platypods to sheep, where the osmoregulatory function of the protein has been applied to differing lifestyles and diverse organ systems. In humans, loss-of-function mutations to CFTR cause the disease cystic fibrosis, which is a significant health burden in populations of white European descent. Orthologue screening has proved fruitful in the pursuit of high-resolution structural data for several membrane proteins, and we have applied some of the princples developed in previous studies to the expression and purification of CFTR. We have overexpressed this protein, along with evolutionarily diverse orthologues, in Saccharomyces cerevisiae and developed a purification to isolate it in quantities sufficient for structural and functional studies. PMID:26517900

  10. Summary and analysis of neutron measurements conducted during the Oak Ridge personnel dosimetry intercomparison studies

    SciTech Connect

    Swaja, R.E.

    1987-01-01

    Since 1974, neutron personnel dosimetry intercomparison studies (PDIS) have been conducted annually at the Oak Ridge National Laboratory's (ORNL) Dosimetry Applications Research Facility. During these studies, neutron dosimeters are mailed to ORNL, exposed to low-level (less than 15 mSv) dose equivalents in a variety of mixed-radiation fields produced using the Health Physics Research Reactor (HPRR), and then returned to the participants for evaluation. Beginning with the Seventh PDIS in 1981, interest and participation in the Oak Ridge intercomparisons increased significantly and consistent and documented techniques for determining reference neutron dose equivalents for the HPRR were introduced. This document presents a summary and analysis of approximately 3400 neutron dose equivalent measurements made using a variety of personnel dosimeters and reported for PDIS 7-12. 16 refs., 3 tabs.

  11. Conducting Probe Atomic Force Microscope as a Relevant Tool for Studying Some Phenomena in MEMS Switches

    NASA Astrophysics Data System (ADS)

    Peschot, A.; Vincent, M.; Poulain, C.; Mariolle, D.; Houzé, F.; Delamare, J.

    2015-12-01

    As the reliability of electrical microcontacts has proved to be the main limitation to a fast-growing production of ultraminiaturized switches, a thorough understanding of their failure mechanisms is an all-important purpose. This paper aims at showing that conducting-probe Atomic Force Microscopy (cp-AFM) is an adequate tool to actuate and study electrical contacts. By choosing relevant cantilevers and operating mode of the cp-AFM, dimensions, gap and force level representative of existing microelectromechanical switches (MEMS switches) are obtained. With two examples, the advantages of using a cp-AFM in force mode for studying physical phenomena at very low scale are highlighted. The reported investigations concern material transfer between contact parts and contact bounces. Those two undesirable phenomena induce surface damages and impinge reliability of MEMS switches. In both cases an explanatory scenario of phenomena occurring at nanoscale is proposed and preventive recommendations for improving the lifetime of such devices are suggested.

  12. Study on the preparation and structural performance of polyaniline/PP conductive fiber

    NASA Astrophysics Data System (ADS)

    Zhang, Hong; Wang, Lijiu

    2007-07-01

    Polyaniline/PP conductive fiber was obtained by in-situ adsorption polymerization. In this work, we discussed the influence of these reaction factors such as adulteration acid concentration, oxidizer concentration, polyaniline monomer content and reaction time to the polymerization and conduct property. In the meanwhile, surface handling with plasma have also been compared for examining the change of polymerization and conduct property. FT-IR spectra analysis and the physic mechanical properties have been used to investigate the structure and properties of conductive fibers. The result shows that with this method of polymerization the conductive property is superior and the conductivity can be reached by 4.5KΩ.

  13. Efficacy of Salvage Radiotherapy Plus 2-Year Androgen Suppression for Postradical Prostatectomy Patients With PSA Relapse

    SciTech Connect

    Choo, Richard; Danjoux, Cyril; Gardner, Sandra; Morton, Gerard; Szumacher, Ewa; Loblaw, D. Andrew; Cheung, Patrick; Pearse, Maria

    2009-11-15

    Purpose: To determine the efficacy of a combined approach of radiotherapy (RT) plus 2-year androgen suppression (AS) as salvage treatment for prostate-specific antigen (PSA) relapse after radical prostatectomy (RP). Methods and Materials: Seventy-five patients with PSA relapse after RP were treated with salvage RT plus 2-year AS, as per a pilot, prospective study. AS started within 1 month after completion of salvage RT and consisted of nilutamide for 4 weeks and buserelin acetate depot subcutaneously every 2 months for 2 years. Relapse-free rate including freedom from PSA relapse was estimated using the Kaplan-Meier method. PSA relapse was defined as a PSA rise above 0.2 ng/mL with two consecutive increases over a minimum of 3 months. A Cox regression analysis was performed to evaluate prognostic factors for relapse. Results: Median age of the cohort was 63 years at the time of salvage RT. Median follow-up from salvage RT was 6.4 years. All achieved initially complete PSA response (< 0.2) with the protocol treatment. Relapse-free rate including the freedom from PSA relapse was 91.5% at 5 years and 78.6% at 7 years. Overall survival rate was 93.2% at both 5 and 7 years. On Cox regression analysis, pT3 stage and PSA relapse less than 2 years after RP were significant prognostic factors for relapse. Conclusion: The combined treatment of salvage RT plus 2-year AS yielded an encouraging result for patients with PSA relapse after RP and needs a confirmatory study.

  14. Safety studies conducted on high-purity trans-resveratrol in experimental animals.

    PubMed

    Williams, Lonnie D; Burdock, George A; Edwards, James A; Beck, Mareike; Bausch, Jochen

    2009-09-01

    trans-Resveratrol is a naturally occurring polyphenolic compound found in a variety of foods, but predominantly in grapes. Safety studies were conducted on high-purity trans-resveratrol (Resvida), including skin and eye irritation, dermal sensitization, subchronic and reproductive toxicity, genotoxicity, and absorption, metabolism and excretion. Resvida was non-irritating to skin and eyes and non-sensitizing. It was non-mutagenic in a bacterial reverse mutation assay in Salmonella typhimurium and Escherichia coli, but exhibited clastogenic activity in a chromosomal aberration test in human lymphocytes. However, in an in vivo bone marrow micronucleus test in rats, Resvida was non-genotoxic. In a 28-day study, Resvida caused no adverse effects in rats at 50, 150 and 500 mg/kg bw/day. Similarly, in a 90-day study, Resvida did not cause any adverse effects in rats at up to 700 mg/kg bw/day; the highest dose tested. Resvida did not induce any adverse reproductive effects in an embryo-fetal toxicity study in rats at a dose of 750 mg/kg bw/day. Also, in vitro and in vivo absorption, metabolism, and excretion studies in Caco-2 cells, rat primary hepatocytes and male and female rats (in vivo) show that Resvida is readily absorbed, metabolized and excreted. These studies provide evidence that Resvida is well tolerated and non-toxic. PMID:19505523

  15. First-Principles study of defects in transparent conducting oxide materials

    NASA Astrophysics Data System (ADS)

    Amini, Mozhgan

    The study of defects and impurities is an important area in semiconductor physics. Defects can be used to control the electronic and optoelectronic properties of materials. However, to achieve such control, knowledge of the fundamental processes that control doping is necessary. First-principles calculations have already made important contributions to the understanding of these fundamental processes of doping in different semiconductors. An important class of materials with an already widespread application area is the transparent conducting oxides (TCOs). These materials combine electrical conductivity and optical transparency and are essential for photovoltaic and optoelectronic applications. The electronic structure of TCOs has therefore been a subject of interest for a long time. In this thesis we provide a first-principles study of defects in TCO materials using density functional theory (DFT). An introduction to TCO materials, their properties, fabrications, and applications are presented in chapter 1. It is followed by a general explanation of the basics of DFT, a quantum mechanical approach for ground state calculations, in chapter 2. Then in chapter 3, different kinds of defects are classified and some important issues such as donor, acceptor, shallow, deep, formation energy, transition level, optical and thermal ionization energies are introduced. In chapter 4, we have used first principles calculations based on DFT to study point defects in CdO within the local density approximation and beyond (LDA+U). Chapter 5 presented the electronic structure and formation energies of group III elements (Al, Ga, In) doped in ZnO. Then in chapter 6, the effect of the presence of both hydrogen and an extrinsic defect (Al, Ga or In) in ZnO is studied. In chapter 7, ZnM2O4 (M=Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides and the formation energies of acceptor-like defects are reported with an advanced hybrid exchange

  16. Guidelines for the Design and Conduct of Clinical Studies in Knee Articular Cartilage Repair

    PubMed Central

    Mithoefer, Kai; Saris, Daniel B.F.; Farr, Jack; Kon, Elizaveta; Zaslav, Kenneth; Cole, Brian J.; Ranstam, Jonas; Yao, Jian; Shive, Matthew; Levine, David; Dalemans, Wilfried; Brittberg, Mats

    2011-01-01

    Objective: To summarize current clinical research practice and develop methodological standards for objective scientific evaluation of knee cartilage repair procedures and products. Design: A comprehensive literature review was performed of high-level original studies providing information relevant for the design of clinical studies on articular cartilage repair in the knee. Analysis of cartilage repair publications and synopses of ongoing trials were used to identify important criteria for the design, reporting, and interpretation of studies in this field. Results: Current literature reflects the methodological limitations of the scientific evidence available for articular cartilage repair. However, clinical trial databases of ongoing trials document a trend suggesting improved study designs and clinical evaluation methodology. Based on the current scientific information and standards of clinical care, detailed methodological recommendations were developed for the statistical study design, patient recruitment, control group considerations, study endpoint definition, documentation of results, use of validated patient-reported outcome instruments, and inclusion and exclusion criteria for the design and conduct of scientifically sound cartilage repair study protocols. A consensus statement among the International Cartilage Repair Society (ICRS) and contributing authors experienced in clinical trial design and implementation was achieved. Conclusions: High-quality clinical research methodology is critical for the optimal evaluation of current and new cartilage repair technologies. In addition to generally applicable principles for orthopedic study design, specific criteria and considerations apply to cartilage repair studies. Systematic application of these criteria and considerations can facilitate study designs that are scientifically rigorous, ethical, practical, and appropriate for the question(s) being addressed in any given cartilage repair research project

  17. A Comparison of Retention Rates among America's 2-Year Institutions of Higher Education

    ERIC Educational Resources Information Center

    Clark, Tampa J.

    2012-01-01

    The purpose of the study was first to calculate the full-time and part-time retention rates for each category of 2-year institution and to examine the differences, if they existed, between and among the three types of colleges. Secondly, the study explored the differences in the full-time and part-time retention rates of first-time students within…

  18. IN-SERVICE HYDRAULIC CONDUCTIVITY OF GCLS IN LANDFILL COVERS - LABORATORY AND FIELD STUDIES

    EPA Science Inventory

    Laboratory experiments using multi-species inorganic solutions (containing calcium and sodium) were conducted on specimens of a new geosynthetic clay liner (GCL) containing sodium bentonite to determine how cation exchange and desiccation affected the hydraulic conductivity. Calc...

  19. Ion transport study in polymer-nanocomposite films by dielectric spectroscopy and conductivity scaling

    NASA Astrophysics Data System (ADS)

    Tripathi, Namrata; Thakur, Awalendra K.; Shukla, Archana; Marx, David T.

    2015-07-01

    The dielectric and conductivity response of polymer nanocomposite electrolytes (films of PMMA4LiClO4 dispersed with nano-CeO2 powder) have been investigated. The dielectric behavior was analyzed via the dielectric permittivity (ε‧) and dissipation factor (tan δ) of the samples. The analysis has shown the presence of space charge polarization at lower frequencies. The real part of ac conductivity spectra of materials obeys the Jonscher power law. Parameters such as dc conductivity, hopping rate, activation energies and the concentration of charge carriers were determined from conductivity data using the Almond West formalism. It is observed that the higher ionic conductivity at higher temperature is due to increased thermally-activated hopping rates accompanied by a significant increase in carrier concentration. The contribution of carrier concentration to the total conductivity is also confirmed from activation energy of migration conduction and from Summerfield scaling. The ac conductivity results are also well correlated with TEM results.

  20. New geoscience teachers division for 2-year colleges

    NASA Astrophysics Data System (ADS)

    Krumm, Debra; Granshaw, Frank

    2011-11-01

    The role of 2-year colleges (2YCs) in geoscience education is growing as the number of students enrolled in Earth and space science courses increases and as these institutions—which include community colleges and junior colleges—provide more students majoring in geoscience at public universities. In recognition of the increasing role of 2YCs in geoscience education, the National Association of Geoscience Teachers (NAGT) recently created a Geo2YC division for faculty, administrators, graduate students, and other geoscience professionals who share a professional interest in geoscience education at 2YCs. The mission of the new division, which is NAGT's first national division, is to serve as a forum for exchanging curricular ideas, concerns, and resources; establish a network of geoscience educators at 2YCs and other institutions with shared interests; sponsor NAGT 2YC activities and make recommendations to the NAGT Council in support of 2YC geoscience education; support and coordinate research on 2YC geoscience education; and advocate for 2YC geoscience education within NAGT and with other organizations.

  1. Environmental studies conducted at the Fenton Hill Hot Dry Rock geothermal development site

    SciTech Connect

    Miera, F.R. Jr.; Langhorst, G.; McEllin, S.; Montoya, C.

    1984-05-01

    An environmental investigation of Hot Dry Rock (HDR) geothermal development was conducted at Fenton Hill, New Mexico, during 1976-1979. Activities at the Fenton Hill Site included an evaluation of baseline data for biotic and abiotic ecosystem components. Identification of contaminants produced by HDR processes that had the potential for reaching the surrounding environment is also discussed. Three dominant vegetative communities were identified in the vicinity of the site. These included grass-forb, aspen, and mixed conifer communities. The grass-forb area was identified as having the highest number of species encountered, with Phleum pratense and Dactylis glomerata being the dominant grass species. Frequency of occurrence and mean coverage values are also given for other species in the three main vegetative complexes. Live trapping of small mammals was conducted to determine species composition, densities, population, and diversity estimates for this component of the ecosystem. The data indicate that Peromyscus maniculatus was the dominant species across all trapping sites during the study. Comparisons of relative density of small mammals among the various trapping sites show the grass-forb vegetative community to have had the highest overall density. Comparisons of small mammal diversity for the three main vegetative complexes indicate that the aspen habitat had the highest diversity and the grass-forb habitat had the lowest. Analyses of waste waters from the closed circulation loop indicate that several trace contaminants (e.g., arsenic, cadmium, fluoride, boron, and lithium) were present at concentrations greater than those reported for surface waters of the region.

  2. What do European veterinary codes of conduct actually say and mean? A case study approach.

    PubMed

    Magalhães-Sant'Ana, M; More, S J; Morton, D B; Osborne, M; Hanlon, A

    2015-06-20

    Codes of Professional Conduct (CPCs) are pivotal instruments of self-regulation, providing the standards to which veterinarians should, and sometimes must, comply. Despite their importance to the training and guidance of veterinary professionals, research is lacking on the scope and emphasis of the requirements set out in veterinary CPCs. This paper provides the first systematic investigation of veterinary CPCs. It relies on a case study approach, combining content and thematic analyses of five purposively selected European CPCs: Federation of Veterinarians of Europe (FVE), Denmark, Ireland, Portugal and the UK. Eight overarching themes were identified, including 'definitions and framing concepts', 'duties to animals', 'duties to clients', 'duties to other professionals', 'duties to competent authorities', 'duties to society', 'professionalism' and 'practice-related issues'. Some differences were observed, which may be indicative of different approaches to the regulation of the veterinary profession in Europe (which is reflected in having a 'code of ethics' or a 'code of conduct'), cultural differences on the status of animals in society, and regulatory bodies' proactivity in adapting to professional needs and to societal changes regarding the status of animals. These findings will contribute to an improved understanding of the roles of CPCs in regulating the veterinary profession in Europe. PMID:25861823

  3. Application of the thermoelectric phenomena to study the unsteady-state thermal conductivity

    NASA Astrophysics Data System (ADS)

    Poprawski, W.; Radojewska, E. B.

    2016-09-01

    We present an experimental set-up designed to investigate the unsteady-state thermal conductivity. A sine-shaped thermal wave is produced by a thermoelectric device and the change in temperature at two points in a metal rod is measured. The investigation is carried out for seven thermal wave frequencies. The thermal wave penetration depth and the thermal conductivity are determined by two methods: from the wave amplitude ratio and from the wave phase shift at two locations. The presented system also offers a determination of the thermal wave propagation velocity and the thermal diffusivity coefficient of the medium. The obtained measurement results are discussed. The specification of the measurement system is preceded by a theoretical and comprehensive description of the phenomena taking part in the experiment. With regard to the role of thermoelectric phenomena in contemporary science and technology the presented experiment is suitable for students in university laboratories studying metrology, electronics, space technology, energy harvesting, energo-mechanics, renewable energy science, chemical technology, bio-engineering and other similar courses.

  4. Density functional theory and conductivity studies of boron-based anion receptors

    SciTech Connect

    Leung, Kevin; Chaudhari, Mangesh I.; Rempe, Susan B.; Fenton, Kyle R.; Pratt, III, Harry D.; Staiger, Chad L.; Nagasubramanian, Ganesan

    2015-07-10

    Anion receptors that bind strongly to fluoride anions in organic solvents can help dissolve the lithium fluoride discharge products of primary carbon monofluoride (CFx) batteries, thereby preventing the clogging of cathode surfaces and improving ion conductivity. The receptors are also potentially beneficial to rechargeable lithium ion and lithium air batteries. We apply Density Functional Theory (DFT) to show that an oxalate-based pentafluorophenyl-boron anion receptor binds as strongly, or more strongly, to fluoride anions than many phenyl-boron anion receptors proposed in the literature. Experimental data shows marked improvement in electrolyte conductivity when this oxalate anion receptor is present. The receptor is sufficiently electrophilic that organic solvent molecules compete with F for boron-site binding, and specific solvent effects must be considered when predicting its F affinity. To further illustrate the last point, we also perform computational studies on a geometrically constrained boron ester that exhibits much stronger gas-phase affinity for both F and organic solvent molecules. After accounting for specific solvent effects, however, its net F affinity is about the same as the simple oxalate-based anion receptor. Lastly, we propose that LiF dissolution in cyclic carbonate organic solvents, in the absence of anion receptors, is due mostly to the formation of ionic aggregates, not isolated F ions.

  5. Density functional theory and conductivity studies of boron-based anion receptors

    DOE PAGESBeta

    Leung, Kevin; Chaudhari, Mangesh I.; Rempe, Susan B.; Fenton, Kyle R.; Pratt, III, Harry D.; Staiger, Chad L.; Nagasubramanian, Ganesan

    2015-07-10

    Anion receptors that bind strongly to fluoride anions in organic solvents can help dissolve the lithium fluoride discharge products of primary carbon monofluoride (CFx) batteries, thereby preventing the clogging of cathode surfaces and improving ion conductivity. The receptors are also potentially beneficial to rechargeable lithium ion and lithium air batteries. We apply Density Functional Theory (DFT) to show that an oxalate-based pentafluorophenyl-boron anion receptor binds as strongly, or more strongly, to fluoride anions than many phenyl-boron anion receptors proposed in the literature. Experimental data shows marked improvement in electrolyte conductivity when this oxalate anion receptor is present. The receptor ismore » sufficiently electrophilic that organic solvent molecules compete with F– for boron-site binding, and specific solvent effects must be considered when predicting its F– affinity. To further illustrate the last point, we also perform computational studies on a geometrically constrained boron ester that exhibits much stronger gas-phase affinity for both F– and organic solvent molecules. After accounting for specific solvent effects, however, its net F– affinity is about the same as the simple oxalate-based anion receptor. Lastly, we propose that LiF dissolution in cyclic carbonate organic solvents, in the absence of anion receptors, is due mostly to the formation of ionic aggregates, not isolated F– ions.« less

  6. A study on the wet etching behavior of AZO (ZnO:Al) transparent conducting film

    NASA Astrophysics Data System (ADS)

    Lin, Y. C.; Jian, Y. C.; Jiang, J. H.

    2008-02-01

    This paper studies the wet etching behavior of AZO (ZnO:Al) transparent conducting film with tetramethylammonium hydroxide (TMAH). The optimum optoelectronic film is prepared first using designated RF power, film thickness and controlled annealing heat treatment parameters. The AZO film is then etched using TMAH etchant and AZ4620 photoresist with controlled etchant concentration and temperature to examine the etching process effect on the AZO film optoelectronic properties. The experimental results show TMAH:H 2O = 2.38:97.62 under 45 °C at the average etch rate of 22 nm/min as the preferred parameters. The activation energy drops as the TMAH concentration rises, while the etch rate increases along with the increase in TMAH concentration and temperature. After lithography, etching and photoresist removal, the conductivity of AZO film dramatically drops from 2.4 × 10 -3 Ω cm to 3.0 × 10 -3 Ω cm, while its transmittance decreases from 89% to 83%. This is due to the poor chemical stability of AZO film against AZ4620 photoresist, leading to an increase in surface roughness. In the photoresist postbaking process, carbon atoms diffused within the AZO film produce poor crystallinity. The slight decreases in zinc and aluminum in the thin film causes a carrier concentration change, which affect the AZO film optoelectronic properties.

  7. Influence of the "second gap" on the transparency of transparent conducting oxides: An ab initio study

    NASA Astrophysics Data System (ADS)

    Ha, Viet-Anh; Waroquiers, David; Rignanese, Gian-Marco; Hautier, Geoffroy

    2016-05-01

    Transparent conducting oxides (TCOs) are essential to many technologies. These materials are doped (n- or p-type) oxides with a large enough band gap (ideally >3 eV) to ensure transparency. However, the high carrier concentration present in TCOs leads additionally to the possibility for optical transitions from the occupied conduction bands to higher states for n-type materials and from lower states to the unoccupied valence bands for p-type TCOs. The "second gap" formed by these transitions might limit transparency, and a large second gap has been sometimes proposed as a design criteria for high performance TCOs. Here, we study the influence of this second gap on optical absorption using ab initio computations for several well-known n- and p-type TCOs. Our work demonstrates that most known n-type TCOs do not suffer from second gap absorption in the visible even at very high carrier concentrations. On the contrary, p-type oxides show lowering of their optical transmission for high carrier concentrations due to second gap effects. We link this dissimilarity to the different chemistries involved in n- versus typical p-type TCOs. Quantitatively, we show that second gap effects lead to only moderate loss of transmission (even in p-type TCOs) and suggest that a wide second gap, while beneficial, should not be considered as a needed criteria for a working TCO.

  8. Change over Time: Conducting Longitudinal Studies of Children’s Cognitive Development

    PubMed Central

    Grammer, Jennie K.; Coffman, Jennifer L.; Ornstein, Peter A.; Morrison, Frederick J.

    2014-01-01

    Developmental scientists have argued that the implementation of longitudinal methods is necessary for obtaining an accurate picture of the nature and sources of developmental change (Magnusson & Cairns, 1996; Morrison & Ornstein, 1996; Magnusson & Stattin, 2006). Developmentalists studying cognition have been relatively slow to embrace longitudinal research, and thus few exemplar studies have tracked individual children’s cognitive performance over time and even fewer have examined contexts that are associated with this growth. In this article we first outline some of the benefits of implementing longitudinal designs. Using illustrations from existing studies of children’s basic cognitive development and of their school-based academic performance, we discuss when it may be appropriate to employ longitudinal (versus other) methods. We then outline methods for integrating longitudinal data into one’s research portfolio, contrasting the leveraging of existing longitudinal data sets with the launching of new longitudinal studies in order to address specific questions concerning cognitive development. Finally, for those who are interested in conducting longitudinal investigations of their own, we provide practical on-the-ground guidelines for designing and carrying out such studies of cognitive development. PMID:24955035

  9. Epidemiology of 577 pediatric firearm fatalities: a 2-year review of the National Trauma Data Bank.

    PubMed

    Oyetunji, Tolulope A; Haider, Adil H; Obirieze, Augustine C; Fisher, Michael; Cornwell, Edward E; Qureshi, Faisal G; Abdullah, Fizan; Nwomeh, Benedict C

    2014-04-01

    The purpose of this study was to delineate the epidemiology of pediatric firearm injuries, including ethno-demographic patterns with impact on years of potential life lost (YPLL). A 2-year review of the National Trauma Data Bank (2007 to 2008) was conducted. Firearm fatalities in records of patients younger than 18 years were identified. Data were analyzed by demographic and injury characteristics and YPLL was calculated by ethnicity. A total of 577 deaths were identified in the pediatric group. Blacks accounted for 49.7 per cent of the fatalities; Hispanics, 19.2 per cent; whites, 17.7 per cent, and other ethnicity, 13.4 per cent. Median Injury Severity Score was 25 with a median Glasgow Coma Scale score of 3. Traumatic brain injury was present in 84.2 per cent of the records. Assault accounted for 72.8 per cent, self-inflicted injury 12.7 per cent, and unintentional injuries were 8.2 per cent. Most firearm fatalities occurred at home (33.6%). By emergency department (ED) disposition, 29.3 per cent died in the ED, 32.9 per cent were admitted to the intensive care unit, and 30.0 per cent taken to the operating room. Blacks had a total of 17,446 YPLL, Hispanics 6,776 YPLL, and whites 6,718 YPLL. Pediatric firearm fatalities still remain an important public health concern. Inclusive gun control policies focused on primary prevention of accidental injuries may be more effective in mitigating its impact. PMID:24887667

  10. Quantitative MRI of the wrist and nerve conduction studies in patients with idiopathic carpal tunnel syndrome

    PubMed Central

    Uchiyama, S; Itsubo, T; Yasutomi, T; Nakagawa, H; Kamimura, M; Kato, H

    2005-01-01

    Objective: To correlate morphological findings of idiopathic carpal tunnel syndrome (CTS) with the function of the median nerve. Methods: In this study, 105 wrists of 105 women patients with idiopathic CTS, and 36 wrists of 36 female volunteers were subjected to nerve conduction studies and MRI. Cross sectional area, signal intensity ratio, and the flattening ratio of the median nerve, carpal tunnel area, flexor tendon area, synovial area, and intersynovial space, and the palmar bowing of the transverse carpal ligament (TCL) were quantified by MRI and correlated with the severity of the disease determined by nerve conduction studies. Results: Cross sectional areas of the median nerve, flexor tendons, and carpal tunnel, and the palmar bowing of the TCL of the CTS groups were greater than in the control group, but differences were not detected among the CTS groups for the area of the flexor tendons and the carpal tunnel. Enlargement, flattening, and high signal intensity of the median nerve at the distal radioulnar joint level were more significant in the advanced than in the earlier stages of the disease. Increase in palmar bowing of the TCL was less prominent in the most advanced group. Linear correlation between the area of the carpal tunnel and palmar bowing of the TCL was noted. Conclusion: Severity of the disease could be judged by evaluating not only longitudinal changes of signal intensity and configuration of the median nerve, but also palmar bowing of the TCL. Increased palmar bowing of the TCL was found to be associated with an increase in the area of the carpal tunnel. PMID:16024888

  11. Mapping Longitudinal Development of Local Cortical Gyrification in Infants from Birth to 2 Years of Age

    PubMed Central

    Li, Gang; Wang, Li; Shi, Feng; Lyall, Amanda E.; Lin, Weili; Gilmore, John H.

    2014-01-01

    Human cortical folding is believed to correlate with cognitive functions. This likely correlation may have something to do with why abnormalities of cortical folding have been found in many neurodevelopmental disorders. However, little is known about how cortical gyrification, the cortical folding process, develops in the first 2 years of life, a period of dynamic and regionally heterogeneous cortex growth. In this article, we show how we developed a novel infant-specific method for mapping longitudinal development of local cortical gyrification in infants. By using this method, via 219 longitudinal 3T magnetic resonance imaging scans from 73 healthy infants, we systemically and quantitatively characterized for the first time the longitudinal cortical global gyrification index (GI) and local GI (LGI) development in the first 2 years of life. We found that the cortical GI had age-related and marked development, with 16.1% increase in the first year and 6.6% increase in the second year. We also found marked and regionally heterogeneous cortical LGI development in the first 2 years of life, with the high-growth regions located in the association cortex, whereas the low-growth regions located in sensorimotor, auditory, and visual cortices. Meanwhile, we also showed that LGI growth in most cortical regions was positively correlated with the brain volume growth, which is particularly significant in the prefrontal cortex in the first year. In addition, we observed gender differences in both cortical GIs and LGIs in the first 2 years, with the males having larger GIs than females at 2 years of age. This study provides valuable information on normal cortical folding development in infancy and early childhood. PMID:24647943

  12. Cytokines as a predictor of clinical response following hip arthroscopy: minimum 2-year follow-up.

    PubMed

    Shapiro, Lauren M; Safran, Marc R; Maloney, William J; Goodman, Stuart B; Huddleston, James I; Bellino, Michael J; Scuderi, Gaetano J; Abrams, Geoffrey D

    2016-08-01

    Hip arthroscopy in patients with osteoarthritis has been shown to have suboptimal outcomes. Elevated cytokine concentrations in hip synovial fluid have previously been shown to be associated with cartilage pathology. The purpose of this study was to determine whether a relationship exists between hip synovial fluid cytokine concentration and clinical outcomes at a minimum of 2 years following hip arthroscopy. Seventeen patients without radiographic evidence of osteoarthritis had synovial fluid aspirated at time of portal establishment during hip arthroscopy. Analytes included fibronectin-aggrecan complex as well as a multiplex cytokine array. Patients completed the modified Harris Hip Score, Western Ontario and McMaster Universities Arthritis Index and the International Hip Outcomes Tool pre-operatively and at a minimum of 2 years following surgery. Pre and post-operative scores were compared with a paired t-test, and the association between cytokine values and clinical outcome scores was performed with Pearson's correlation coefficient with an alpha value of 0.05 set as significant. Sixteen of seventeen patients completed 2-year follow-up questionnaires (94%). There was a significant increase in pre-operative to post-operative score for each clinical outcome measure. No statistically significant correlation was seen between any of the intra-operative cytokine values and either the 2-year follow-up scores or the change from pre-operative to final follow-up outcome values. No statistically significant associations were seen between hip synovial fluid cytokine concentrations and 2-year follow-up clinical outcome assessment scores for those undergoing hip arthroscopy. PMID:27583163

  13. Cytokines as a predictor of clinical response following hip arthroscopy: minimum 2-year follow-up

    PubMed Central

    Shapiro, Lauren M.; Safran, Marc R.; Maloney, William J.; Goodman, Stuart B.; Huddleston, James I.; Bellino, Michael J.; Scuderi, Gaetano J.; Abrams, Geoffrey D.

    2016-01-01

    Hip arthroscopy in patients with osteoarthritis has been shown to have suboptimal outcomes. Elevated cytokine concentrations in hip synovial fluid have previously been shown to be associated with cartilage pathology. The purpose of this study was to determine whether a relationship exists between hip synovial fluid cytokine concentration and clinical outcomes at a minimum of 2 years following hip arthroscopy. Seventeen patients without radiographic evidence of osteoarthritis had synovial fluid aspirated at time of portal establishment during hip arthroscopy. Analytes included fibronectin–aggrecan complex as well as a multiplex cytokine array. Patients completed the modified Harris Hip Score, Western Ontario and McMaster Universities Arthritis Index and the International Hip Outcomes Tool pre-operatively and at a minimum of 2 years following surgery. Pre and post-operative scores were compared with a paired t-test, and the association between cytokine values and clinical outcome scores was performed with Pearson’s correlation coefficient with an alpha value of 0.05 set as significant. Sixteen of seventeen patients completed 2-year follow-up questionnaires (94%). There was a significant increase in pre-operative to post-operative score for each clinical outcome measure. No statistically significant correlation was seen between any of the intra-operative cytokine values and either the 2-year follow-up scores or the change from pre-operative to final follow-up outcome values. No statistically significant associations were seen between hip synovial fluid cytokine concentrations and 2-year follow-up clinical outcome assessment scores for those undergoing hip arthroscopy. PMID:27583163

  14. Optical studies of the charge localization and delocalization in conducting polymers

    NASA Astrophysics Data System (ADS)

    Kim, Youngmin

    A systematic charge transport study on the thermochromism of polyaniline (PAN) doped with a plasticizing dopant, and on a field effect device using conducting poly (3,4-ethylenedioxythiophene) (PEDOT) as its active material, was made at optical (20--45,000 cm-1) frequencies to probe the charge localization and delocalization phenomena and the insulator to metal transition (IMT) in the inhomogeneous conducting polymer system. Temperature dependent reflectance [20--8000 cm -1 (2.5 meV--1eV)] of the PAN sample, together with absorbance and do transport study done by Dr. Pron at the Laboratoire de Physique des Metaux Synthetiques in Grenoble, France, shows spectral weight loss in the infrared region but the reflectance in the very low frequency (below 100 cm-1) remains unaffected. There are two localization transitions. The origin of the 200 K localization transition that affect >˜15% of the electrons is the glass transition emanating from the dopants. The transition principally affects the IR response in the range of 200--8000 cm -1. The low temperature (<75K) localization transition affects the few electrons that provide the high conductivity. It is suggested that these electrons are localized by disorder at the lowest temperature and become delocalized through phonon induced delocalization as the temperature increases to 75K. It is noted that this temperature is typical of a Debye temperature in many organic materials. The thermocromism is attributed to the weak localization to strong localization transition through the glass transition temperature. Below the glass transition temperature (Tg), the lattice is "frozen" in configuration that reduces the charge delocalization and lead to cause increase of strongly localized polarons. Time variation of source-drain current, real-time IR reflectance [20--8000 cm-1 (2.5 meV--1eV)] modulation, and real-time UV/VIS/NIR absorbance [380--2400 nm (0.5--3.3 eV)] modulation were measured to investigate the field induced charge

  15. Computational studies of solid-state alkali conduction in rechargeable alkali-ion batteries

    DOE PAGESBeta

    Deng, Zhi; Mo, Yifei; Ong, Shyue Ping

    2016-03-25

    The facile conduction of alkali ions in a crystal host is of crucial importance in rechargeable alkali-ion batteries, the dominant form of energy storage today. In this review, we provide a comprehensive survey of computational approaches to study solid-state alkali diffusion. We demonstrate how these methods have provided useful insights into the design of materials that form the main components of a rechargeable alkali-ion battery, namely the electrodes, superionic conductor solid electrolytes and interfaces. We will also provide a perspective on future challenges and directions. Here, the scope of this review includes the monovalent lithium- and sodium-ion chemistries that aremore » currently of the most commercial interest.« less

  16. Synthesis, characterization and conductivity studies of ZnFe{sub 2}O{sub 4} nanoparticles

    SciTech Connect

    Narsimulu, D.; Satyanarayana, N.; Venkateswarlu, M.

    2015-06-24

    Transition metal ferrites with general formula AB{sub 2}O{sub 4} (A=Co, Cu, Mn, Zn, B=Fe{sup +3}) could be used as an anode materials in lithium ion battery (LIB), because, lithium ion batteries fabricated using ferrite materials show the high capacity than commonly used graphite. The ZnFe{sub 2}O{sub 4} with cubic spinel structured material was prepared by acrylamide assisted citrate combustion process. Phase, structural coordination and thermal behavior of the prepared ZnFe{sub 2}O{sub 4} were confirmed by powder X-ray diffraction, FTIR spectra and TG/DTA thermogram respectively. Morphology and specific surface area of the ZnFe{sub 2}O{sub 4} were identified by SEM and BET surface analyzer respectively and its conductivity studies were made through impedance spectroscopy.

  17. Synthesis, characterization and conductivity studies of ZnFe2O4 nanoparticles

    NASA Astrophysics Data System (ADS)

    Narsimulu, D.; Venkateswarlu, M.; Satyanarayana, N.

    2015-06-01

    Transition metal ferrites with general formula AB2O4 (A=Co, Cu, Mn, Zn, B=Fe+3) could be used as an anode materials in lithium ion battery (LIB), because, lithium ion batteries fabricated using ferrite materials show the high capacity than commonly used graphite. The ZnFe2O4 with cubic spinel structured material was prepared by acrylamide assisted citrate combustion process. Phase, structural coordination and thermal behavior of the prepared ZnFe2O4 were confirmed by powder X-ray diffraction, FTIR spectra and TG/DTA thermogram respectively. Morphology and specific surface area of the ZnFe2O4 were identified by SEM and BET surface analyzer respectively and its conductivity studies were made through impedance spectroscopy.

  18. [Is it necessary to conduct a urodynamic study in the diagnosis of urinary incontinence?].

    PubMed

    Juarranz Sanz, M; Campos López-Carrión, M; Fernández-Micheltorena, C; Sánchez Sánchez, D

    2006-03-01

    Urinary incontinence is a dysfunction that affects 20%-50% of the women in Spain, depending on age. Even though it does not involve a prognosis of severity, it reduces self-esteem, limits independence and clear deteriorates quality of life. The diagnosis is generally made following the international criteria collected in the clinical practice guidelines. Even if it is true that the symptoms make it possible to suspect the nature of the functional disorder, this is not always sufficient or conclusive and there may be errors even in the clearest cases. Even so, the need to conduct a urodynamic study in the assessment of women with urinary incontinence diagnosed according to the symptoms mentioned continues to be debatable and there are no unified and defined criteria in our setting in regards to when it is necessary to request urodynamic tests. PMID:16597382

  19. The use of nerve conduction studies in determining the short-term outcome of Bell's palsy.

    PubMed

    Prakash, K M; Raymond, A A

    2003-03-01

    Bell's palsy is a common neurological problem causing considerable loss of self-esteem among patients. A prospective observational study was conducted to determine the short-term outcome of Bell's palsy at 1 month and 2 months after the onset and the relationship between these outcomes with facial nerve degeneration. We also determined if gender, age, diabetes, systolic and diastolic blood pressure influence the severity of facial nerve degeneration and the clinical outcome at 2 months after the onset. After clinically grading the newly diagnosed unilateral Bell's palsy patients using the House-Brackmann facial nerve grading system, nerve conduction studies of the facial nerve were done to determine the severity of facial nerve degeneration. The recovery of the facial paralysis was clinically graded again at the end of 1 month and 2 months from the onset. A total of 37 patients were recruited. There was a strong positive correlation between facial nerve degeneration and the clinical outcome of Bell's palsy at 1 month (r = 0.794; p < 0.0005) and 2 months (r = 0.732; p < 0.0005) after the onset. There was no significant correlation between either the facial nerve degeneration or the clinical outcome at 2 months with the patients' age (p = 0.288 and p = 0.799 respectively), systolic blood pressure (p = 0.425 and p = 0.933 respectively) or diastolic blood pressure (p = 0.243 and p = 0.579 respectively). Neither the severity of facial nerve degeneration nor the clinical outcome at 2 months were significantly different between male and female patients (p = 0.460 and p = 0.725 respectively) or diabetic and non-diabetic patients (p = 0.655 and p = 0.655 respectively). PMID:14556328

  20. A Survey of Community College Enrollment Conducted as Part of Fee Impact Study. Second Follow-Up Measure, Spring, 1986.

    ERIC Educational Resources Information Center

    Field Research Corp., San Francisco, CA.

    A three-phase study was conducted in California to assess the impact of a mandatory fee imposed in 1985 on enrollments in the California community colleges as measured by changes in students' ethnicity, income, and academic load, and changes in enrollment in college non-credit education. A benchmark study conducted in spring 1984 prior to the…

  1. Electric field studies: TLE-induced waveforms and ground conductivity impact on electric field propagation

    NASA Astrophysics Data System (ADS)

    Farges, Thomas; Garcia, Geraldine; Blanc, Elisabeth

    2010-05-01

    propagation of the electromagnetic waves generated by lightning has also been studied in the frequency range 1 kHz-1MHz at distances lower than 1000 km from the lightning source. A propagation model has been developed to determine the ground waves which propagate in a homogenous medium using the analytical expression given by Maclean and Wu [1993]. This approach takes into account the electric finite conductivity and the fact that the Earth is spherical, which allow us to deal with over-the-horizon propagation. We installed in 2008 four stations which were more or less aligned - the maximum distance between two stations was about 870 km. Two stations were located close to the Mediterranean Sea and the two others inside the continent, at the centre of France. This station distribution and the observation period (from August to December) allowed statistical and physical studies, such as the influence of the electric conductivity on wave propagation. Comparison of electric field spectra, measured after propagation only over sea and only over ground, showed clearly the effects of ground conductivity on propagation. Comparison between observations and modelling has been used to evaluate the ground conductivity. In the future we will implement the sky-wave inside our model and validate it with the database.

  2. Developing and Conducting a Dissertation Study through the Community-Based Participatory Research Approach

    PubMed Central

    Nadimpalli, S.B.; Van Devanter, N.; Kavathe, R.; Islam, N.

    2016-01-01

    The community-based participatory research (CBPR) approach has been shown to be innovative and effective in conducting research with communities experiencing health disparities. Doctoral nursing students, and other doctoral students in the health sciences, who are interested in this approach can benefit through structured CBPR training experiences in learning how to engage with communities, build community capacity, share resources, implement CBPR study plans, and disseminate results of CBPR-focused studies. The objectives of this case-study are to demonstrate ways in which one doctoral student aligned with academic mentors and a funded CBPR project to build a relationship with the Sikh Asian Indian (AI) community of New York City to develop and implement a CBPR-focused doctoral dissertation study. The purpose of the research was to examine the relationship between the experience of perceived discrimination and health outcomes in this community. CBPR methods utilized in developing the study entailed the author partaking in formal and informal CBPR learning experiences, building relationships with community and academic partners early on through volunteering, developing a research plan in collaboration with members of the community and academic partners, identifying an appropriate setting and methods for recruitment and data collection, increasing capacity and resources for all partners (the author, community, and academic), and presenting dissertation study findings to the community. In conclusion, CBPR-focused doctoral experiences are novel pedagogical and professional approaches for nursing and health science students which can lead to mutual benefits for all involved, and ultimately successful and effective community-based health research. PMID:27489882

  3. The REporting of studies Conducted using Observational Routinely-collected health Data (RECORD) Statement

    PubMed Central

    Benchimol, Eric I.; Smeeth, Liam; Guttmann, Astrid; Harron, Katie; Moher, David; Petersen, Irene; Sørensen, Henrik T.; von Elm, Erik; Langan, Sinéad M.

    2015-01-01

    Routinely collected health data, obtained for administrative and clinical purposes without specific a priori research goals, are increasingly used for research. The rapid evolution and availability of these data have revealed issues not addressed by existing reporting guidelines, such as Strengthening the Reporting of Observational Studies in Epidemiology (STROBE). The REporting of studies Conducted using Observational Routinely collected health Data (RECORD) statement was created to fill these gaps. RECORD was created as an extension to the STROBE statement to address reporting items specific to observational studies using routinely collected health data. RECORD consists of a checklist of 13 items related to the title, abstract, introduction, methods, results, and discussion section of articles, and other information required for inclusion in such research reports. This document contains the checklist and explanatory and elaboration information to enhance the use of the checklist. Examples of good reporting for each RECORD checklist item are also included herein. This document, as well as the accompanying website and message board (http://www.record-statement.org), will enhance the implementation and understanding of RECORD. Through implementation of RECORD, authors, journals editors, and peer reviewers can encourage transparency of research reporting. PMID:26440803

  4. Thermal boundary conductance enhancement using experimentally achievable nanostructured interfaces - analytical study combined with molecular dynamics simulation.

    PubMed

    Lee, Eungkyu; Zhang, Teng; Hu, Ming; Luo, Tengfei

    2016-06-22

    Interfacial thermal resistance presents great challenges to the thermal management of modern electronics. In this work, we perform an analytical study to enhance the thermal boundary conductance (TBC) of nanostructured interfaces with square-shape pillar arrays, extendable to the characteristic lengths that can be fabricated in practice. As a representative system, we investigate a SiC substrate with the square-shape pillar array combined with epitaxial GaN as the nanostructured interface. By applying a first-order ray tracing method and molecular dynamics simulations to analyze phonon incidence and transmission at the nanostructured interface, we systematically study the impact of the characteristic dimensions of the pillar array on the TBC. Based on the multi-scale analysis we provide a general guideline to optimize the nanostructured interfaces to achieve higher TBC, demonstrating that the optimized TBC value of the nanostructured SiC/GaN interfaces can be 42% higher than that of the planar SiC/GaN interfaces without nanostructures. The model used and results obtained in this study will guide the further experimental realization of nanostructured interfaces for better thermal management in microelectronics. PMID:27275647

  5. Studies of structural, optical, dielectric relaxation and ac conductivity of different alkylbenzenesulfonic acids doped polypyrrole nanofibers

    NASA Astrophysics Data System (ADS)

    Hazarika, J.; Kumar, A.

    2016-01-01

    Polypyrrole (PPy) nanofibers doped with alkylbenzenesulfonic acids (ABSA) have been synthesized using interfacial polymerization method. HRTEM studies confirm the formation of PPy nanofibers with average diameter ranging from 13 nm to 25 nm. Broad X-ray diffraction peak in 2 θ range 20-23.46° reveals amorphous structure of PPy nanofibers. The ordering or crystallinity of polymer chains increases, while their interplanar spacing (d) and interchain separation (R) decreases for short alkyl chain ABSA doped PPy nanofibers. FTIR studies reveal that short alkyl chain ABSA doped PPy nanofibers show higher value of "effective conjugation length". PPy nanofibers doped with short alkyl chain ABSA dopant exhibit smaller optical band gap. TGA studies show enhanced thermal stability of short alkyl chain ABSA doped PPy nanofibers. Decrease in dielectric permittivity ε ‧ (ω) with increasing frequency suggests presence of electrode polarization effects. Linear decrease in dielectric loss ε ″ (ω) with increasing frequency suggests dominant effect of dc conductivity process. Low value of non-exponential exponent β (<1) reveals non-Debye relaxation of charge carriers. Scaling of imaginary modulus (M ″) reveals that the charge carriers follow the same relaxation mechanism. Moreover, the charge carriers in PPy nanofibers follow the correlated barrier hopping (CBH) transport mechanism.

  6. Experimental and numerical study of the effective thermal conductivity of silica nanocomposites with thermal boundary resistance

    SciTech Connect

    Kothari, Rushabh M; Dinwiddie, Ralph Barton; Wang, Hsin

    2013-01-01

    . The current study presents experimental study of thermal boundary resistance for silica nano particles embedded inside epoxy resin. The bulk conductivity of the sample is measured and Rc is back calculated using Hasselman-Johnson s (H-J) equation. The numerical validation of the equation is also presented, including extrapolation study to predict effective conductivity of the nanocomposite TIM.

  7. A study of the conductive properties of nanostructured metal oxide films

    NASA Astrophysics Data System (ADS)

    D'Olembert, Andre A.

    Fuel cells which were first employed in spacecraft, producing both electricity and water for astronaut consumption during the mid-1960's, are part of the ongoing pursuit for renewable energy sources, and environmentally compatible electric power generation. Recent enhancements in design and materials might establish fuel cells in a sustainable hydrogen energy economy (SHEE) as viable alternatives to the internal combustion engine. In tune with our principal objectives, this study investigates the conductive properties of metal-oxide thin films by developing a new deposition technique called dual channel ultrasonic spray pyrolysis (DC-USP). The DC-USP process has proved to be a reliable and cost-effective method to fabricate thin films. Extending the DC-USP technique, we have created a novel mixed ionic electronic conductor (MIEC) composed of two metal-oxides: lanthanum strontium ferrite and copper-doped bismuth vanadate (LSF.40:BiCuVOx.10). When the two materials are mixed, their grain boundary regions are heavily defected because of the dissimilarity of the two crystal structures, which maintain their integrity in the formed heterogenous composite. Oxygen ion diffusion occurs as it migrates through an ionic crystal, hopping from defect site to defect site. Furthermore, a nanostructured material - with crystallite grains less than 100 nm in diameter - will improve oxygen diffusion by increasing the density of defect sites. The rate of diffusion is increased as well as the quantity of diffusion pathways. Ultimately, as the ionic current density is increased, the total efficiency (nuSOFCtotal) of the solid oxide fuel cell (SOFC) can be improved. Therefore, the LSF-40:BiCuVOx.10 material can contribute to solve the major outstanding problem of the three-phase boundary (TPB) that limits the oxygen reduction reaction to within a microscopic region near the cathode-electrolyte interface in the SOFC device. Materials were tested and analyzed using atomic force microscopy

  8. Excess protons in water-acetone mixtures. II. A conductivity study.

    PubMed

    Semino, Rocío; Longinotti, M Paula

    2013-10-28

    In the present work we complement a previous simulation study [R. Semino and D. Laria, J. Chem. Phys. 136, 194503 (2012)] on the disruption of the proton transfer mechanism in water by the addition of an aprotic solvent, such as acetone. We provide experimental measurements of the mobility of protons in aqueous-acetone mixtures in a wide composition range, for water molar fractions, xw, between 0.05 and 1.00. Furthermore, new molecular dynamics simulation results are presented for rich acetone mixtures, which provide further insight into the proton transport mechanism in water-non-protic solvent mixtures. The proton mobility was analyzed between xw 0.05 and 1.00 and compared to molecular dynamics simulation data. Results show two qualitative changes in the proton transport composition dependence at xw ∼ 0.25 and 0.8. At xw < 0.25 the ratio of the infinite dilution molar conductivities of HCl and LiCl, Λ(0)(HCl).Λ(0)(LiCl)(-1), is approximately constant and equal to one, since the proton diffusion is vehicular and equal to that of Li(+). At xw ∼ 0.25, proton mobility starts to differ from that of Li(+) indicating that above this concentration the Grotthuss transport mechanism starts to be possible. Molecular dynamics simulation results showed that at this threshold concentration the probability of interconversion between two Eigen structures starts to be non-negligible. At xw ∼ 0.8, the infinite molar conductivity of HCl concentration dependence qualitatively changes. This result is in excellent agreement with the analysis presented in the previous simulation work and it has been ascribed to the interchange of water and acetone molecules in the second solvation shell of the hydronium ion. PMID:24182052

  9. Microvasculature and incident atrioventricular conduction abnormalities in the Multi-Ethnic Study of Atherosclerosis (MESA).

    PubMed

    Chacko, Billy G; Edwards, Matthew S; Sharrett, A Richey; Qureshi, Waqas T; Klein, Barbara E K; Klein, Ronald; Herrington, David M; Soliman, Elsayed Z

    2015-10-01

    Abnormalities of the microvasculature are linked to major cardiac events, but their role in the development of atrioventricular conduction abnormalities (AVCA) is unknown. We examined the association between central retinal arteriolar equivalent (CRAE), a measure of the microvasculature, and incident AVCA. This analysis included 3975 participants free of AVCA at baseline from the Multi-Ethnic Study of Atherosclerosis (MESA). Incident AVCA was defined as a composite of new heart rate-adjusted PR interval ⩾ 200 ms (first-degree AV block) and advanced block (second-degree or complete AV block) detected from the MESA exam 5 electrocardiogram (ECG). CRAE was measured from retinal photographs at exam 2. Both ECGs and retinal photographs were collected using standardized methods and read and graded at central core labs. Incident AVCA were present in 7.4% (n=290) of the participants, of which 94% were first-degree AV block. Incident AVCA were increasingly more common in participants with narrower CRAE (4.6% in Q4, 6.4% in Q3, 7.0% in Q2 and 10.8% in Q1, p-value for trend < 0.0001). The socio-demographic and cardiovascular disease risk-adjusted odds of incident AVCA in the Q1 group (the group with the narrowest retinal arteriolar diameter) was nearly twice the odds in the Q4 group (OR: 1.68, 95% CI: 1.15-2.51). This association remained significant after adjustment for major ECG abnormalities and incident cardiovascular disease (Q1 vs Q4, OR: 1.65, 95% CI: 1.01-2.71). In conclusion, narrower retinal arteriolar caliber is associated with development of new AV conduction abnormalities. PMID:25999364

  10. Thermomechanical coupling, heat conduction and director rotation in cholesteric liquid crystals studied by molecular dynamics simulation.

    PubMed

    Sarman, Sten; Laaksonen, Aatto

    2013-03-14

    The lack of a centre of inversion in a cholesteric liquid crystal allows linear cross couplings between thermodynamic forces and fluxes that are polar vectors and pseudovectors, respectively. This makes it possible for a temperature gradient parallel to the cholesteric axis to induce a torque that rotates the director, a phenomenon known as the Lehmann effect or thermomechanical coupling. The converse is also possible: a torque applied parallel to the cholesteric axis rotates the director and drives a heat flow. In order to study this phenomenon, nonequilibrium molecular dynamics simulation algorithms and Green-Kubo relations evaluated by equilibrium molecular dynamics simulation have been used to calculate the Leslie coefficient, i.e. the cross coupling coefficient between the temperature gradient and the director angular velocity, for a model system composed of soft prolate ellipsoids of revolution interacting via the Gay-Berne potential augmented by a chiral interaction potential causing the formation of a cholesteric phase. It is found that the Leslie coefficient is two orders of magnitudes smaller than other transport coefficients such as the heat conductivity and the twist viscosity, so that very long simulations are required to evaluate it. The Leslie coefficient decreases with the pitch but it has not been possible to determine the exact functional dependence of this coefficient on the pitch. Since very long simulations have been performed to evaluate the Leslie coefficient, very accurate values have been obtained for the twist viscosity and the heat conductivity as a by-product and it is found that they are very similar to the values of the corresponding quantities in the achiral nematic phase that arises when the pitch goes to infinity. PMID:23223192

  11. An Experimental Study of the Effects of A Rotating Magnetic Field on Electrically Conducting Aqueous Solutions

    NASA Technical Reports Server (NTRS)

    Ramachandran Narayanan; Mazuruk, Konstantin

    1998-01-01

    The use of a rotating magnetic field for stirring metallic melts has been a commonly adopted practice for a fairly long period. The elegance of the technique stems from its non-intrusive nature and the intense stirring it can produce in an electrically conducting medium. A further application of the method in recent times has been in the area of crystal growth from melts (e.g. germanium). The latter experiments have been mainly research oriented in order to understand the basic physics of the process and to establish norms for optimizing such a technique for the commercial production of crystals. When adapted for crystal growth applications, the rotating magnetic field is used to induce a slow flow or rotation in the melt which in effect significantly curtails temperature field oscillations in the melt. These oscillations are known to cause dopant striations and thereby inhomogeneities in the grown crystal that essentially degrades the crystal quality. The applied field strength is typically of the order of milli-Teslas with a frequency range between 50-400 Hz. In this investigation, we report findings from experiments that explore the feasibility of applying a rotating magnetic field to aqueous salt solutions, that are characterized by conductivities that are several orders of magnitude smaller than semi-conductor melts. The aim is to study the induced magnetic field and consequently the induced flow in such in application. Detailed flow field description obtained through non-intrusive particle displacement tracking will be reported along with an analytical assessment of the results. It is anticipated that the obtained results will facilitate in establishing a parameter range over which the technique can be applied to obtain a desired flow field distribution. This method can find applicability in the growth of crystals from aqueous solutions and give an experimenter another controllable parameter towards improving the quality of the grown crystal.

  12. Sage grouse on the Yakima Training Center: A summary of studies conducted during 1989 and 1990

    SciTech Connect

    Eberhardt, L.E. ); Hofmann, L.A. . Coe-Truman Technologies)

    1991-03-01

    A two-year study, sponsored by the U.S. Department of the Army and conducted by Pacific Northwest Laboratory, was initiated in 1989 to study sage grouse on the Yakima Training Center (YTC). The specific objectives of this study were (1) to obtain detailed information on the distribution and relative density of sage grouse on the YTC, (2) to identify movement and habitat use patterns of sage grouse on the YTC, (3) to identify crucial habitat for sage grouse on the YTC, and (4) to provide management recommendations. Sage grouse were selected for study because they are a US Fish and Wildlife Service candidate species for the threatened and endangered list in Washington, and because the YTC probably contains the largest population of sage grouse left on federally owned lands in this state. The locations of 11 sage grouse leks, or breeding grounds, were determined on the YTC during extensive spring helicopter surveys. The maximum number of sage grouse observed during ground surveys of these leks varied from 2 to 55 birds. One lek, located near Range 19, was probably used by 40 to 50% of the YTC sage grouse population. Fifteen years of counts of males on leks indicate that the YTC sage grouse population was most numerous during the early to mid 1980s. Since the mid-1980s, sage grouse numbers appear to have declined on the YTC and in other locations in Washington. Forty-six sage grouse (17 females and 29 males) were captured and fitted with radio transmitters during 1989 and 1990. Movements by these sage grouse were both erratic and large when compared with other studies. We believe that many of the atypical movements were in response to military training activities. Sage grouse appeared to seek out areas on the YTC where human disturbance was low. Recommendations are made for improving the management of grouse habitat.

  13. An experimental study of perovskite-structured mixed ionic- electronic conducting oxides and membranes

    NASA Astrophysics Data System (ADS)

    Zeng, Pingying

    In recent decades, ceramic membranes based on mixed ionic and electronic conducting (MIEC) perovskite-structured oxides have received many attentions for their applications for air separation, or as a membrane reactor for methane oxidation. While numerous perovskite oxide materials have been explored over the past two decades; there are hardly any materials with sufficient practical economic value and performance for large scale applications, which justifies continuing the search for new materials. The main purposes of this thesis study are: (1) develop several novel SrCoO3-delta based MIEC oxides, SrCoCo1-xMxO3-delta, based on which membranes exhibit excellent oxygen permeability; (2) investigate the significant effects of the species and concentration of the dopants M (metal ions with fixed valences) on the various properties of these membranes; (3) investigate the significant effects of sintering temperature on the microstructures and performance of oxygen permeation membranes; and (4) study the performance of oxygen permeation membranes as a membrane reactor for methane combustion. To stabilize the cubic phase structure of the SrCoO3-delta oxide, various amounts of scandium was doped into the B-site of SrCoO 3-delta to form a series of new perovskite oxides, SrScxCoCo 1-xO3-delta (SSCx, x = 0-0.7). The significant effects of scandium-doping concentration on the phase structure, electrical conductivity, sintering performance, thermal and structural stability, cathode performance, and oxygen permeation performance of the SSCx membranes, were systematically studied. Also for a more in-depth understanding, the rate determination steps for the oxygen transport process through the membranes were clarified by theoretical and experimental investigation. It was found that only a minor amount of scandium (5 mol%) doping into the B-site of SrCoO3-delta can effectively stabilize the cubic phase structure, and thus significantly improve the electrical conductivity and

  14. A study on the stability of n-type conductive polymer

    NASA Astrophysics Data System (ADS)

    Onoda, M.

    2016-04-01

    Novel n-type conducting polymer, poly (p-methylpyridinium vinylene), PMePyV were synthesized by using the quaternization of poly (p-pyridyl vinylene), PPyV and several regiochemical consequences in this polymer were proposed. The electrical, optical, and electrochemical properties of n-type conductive polymer were observed. In addition, a possibility of a variety of functional applications of n-type conductive polymer was indicated.

  15. Effect of Elbow Position on Short-segment Nerve Conduction Study in Cubital Tunnel Syndrome

    PubMed Central

    Liu, Zhu; Jia, Zhi-Rong; Wang, Ting-Ting; Shi, Xin; Liang, Wei

    2016-01-01

    Background: The appropriate elbow position of short-segment nerve conduction study (SSNCS) to diagnose cubital tunnel syndrome (CubTS) is still controversial. The goal of this study was to determine the effect of different elbow positions at full extension and 70° flexion on SSNCS in CubTS. Methods: In this cross-sectional study, the clinical data of seventy elbows from 59 CubTS patients between September, 2011 and December, 2014 in the Peking University First Hospital were included as CubTS group. Moreover, thirty healthy volunteers were included as the healthy group. SSNCS were conducted in all subjects at elbow full extension and 70° elbow flexion. Paired nonparametric test, bivariate correlation, Bland–Altman, and Chi-squared test analysis were used to compare the effectiveness of elbow full extension and 70° flexion elbow positions on SSNCS in CubTS patients. Results: Data of upper limit was calculated from healthy group, and abnormal latency was judged accordingly. CubTS group's latency and compound muscle action potential (CMAP) of each segment at 70° elbow flexion by SSNCS was compared with full extension position, no statistically significant difference were found (all P > 0.05). Latency and CMAP of each segment at elbow full extension and 70° flexion were correlated (all P < 0.01), except the latency of segment of 4 cm to 6 cm above elbow (P = 0.43), and the latency (P = 0.15) and the CMAP (P = 0.06) of segment of 2 cm to 4 cm below elbow. Bivariate correlation and Bland–Altman analysis proved the correlation between elbow full extension and 70° flexion. Especially in segments across the elbow (2 cm above the elbow and 2 cm below it), latency at elbow full extension and 70° flexion were strong direct associated (r = 0.83, P < 0.01; r = 0.55, P < 0.01), and so did the CMAP (r = 0.49, P < 0.01; r = 0.72, P < 0.01). There was no statistically significant difference in abnormality of each segment at full extension as measured by SSNCS compared with

  16. Trajectories of adolescent conduct problems in relation to cortical thickness development: a longitudinal MRI study.

    PubMed

    Oostermeijer, S; Whittle, S; Suo, C; Allen, N B; Simmons, J G; Vijayakumar, N; van de Ven, P M; Jansen, L M C; Yücel, M; Popma, A

    2016-01-01

    Multiple cross-sectional imaging studies have identified structural abnormalities in prefrontal, temporal and limbic regions related to conduct problems (CPs). However, the relationship between development of such neurobiological deficits and developmental pathways of CPs has remained unclear. The current study investigated distinct trajectories of CP and related trajectories of cortical thickness within a community-based sample of adolescents (n=239), age range 12-19, to address this gap. Three trajectory classes were revealed using latent class growth analyses (LCGAs), comprising a 'desisting' CP group, an 'intermediate' CP group and a 'stable low' CP group. Structural magnetic resonance imaging (MRI) scans were collected with a subgroup of 171 adolescents at three waves throughout adolescence (ages 12, 16 and 19). Generalized estimating equation (GEE) analysis-comparing longitudinal changes in cortical thickness and subcortical volume between CP groups for several regions of interest (ROIs)-showed that these CP groups had differential trajectories of cortical thickness in the dorsolateral prefrontal cortex (dl-PFC), and the anterior cingulate cortex (ACC), and volume of the hippocampus. Adolescents in the desisting CP group showed an attenuation of the typical pattern of cortical thinning as present in the intermediate and stable low CP groups, in addition to an exaggeration of the typical pattern of hippocampal volume increase. These findings suggest that a deviant cortical thickness trajectory was related to a desisting CP pathway across adolescence. Such deviant neurodevelopmental growth trajectories may act as an underlying mechanism for developmental CP pathways, and possibly distinguish desisting antisocial adolescents. PMID:27327256

  17. Safety studies conducted on a proprietary high-purity aloe vera inner leaf fillet preparation, Qmatrix.

    PubMed

    Williams, Lonnie D; Burdock, George A; Shin, Eunju; Kim, Seunghyun; Jo, T H; Jones, Kenneth N; Matulka, Ray A

    2010-06-01

    The aloe vera plant has a long history of safe use for oral and topical applications. This publication describes safety studies conducted on a proprietary high-purity aloe vera inner leaf fillet preparation, Qmatrix. In a 13-week study in rats, Qmatrix was administered via gavage at 0, 500, 1000 and 2000 mg/kg body weight (bw)/day. There were no significant changes in food or water consumption, body weight, serum biochemistry or hematology at any of the doses tested. Sporadic, significant increases were observed in some of the measured urinalysis parameters; however, these variations were not treatment-related, as most were observed only in one sex, not dose-dependent and within historical control values. Organ weights were unaffected, except for a statistically significant, though not dose-dependent, increase in absolute and relative weights of the right kidney in males at 500 and 2000 mg/kg bw/day, respectively. Histopathological analysis revealed no abnormal signs. Qmatrix was non-mutagenic in an Ames test and a chromosomal aberration test at concentrations up to 10,000 microg/plate, and in an in vivo bone marrow micronucleus test at doses up to 5000 mg/kg bw/day. Based on these results, Qmatrix is not genotoxic in vitro or in vivo and; has an oral NOAEL greater than 2000 mg/kg bw/day following 90 days of oral exposure. PMID:20096744

  18. The MAL-ED study: a multinational and multidisciplinary approach to understand the relationship between enteric pathogens, malnutrition, gut physiology, physical growth, cognitive development, and immune responses in infants and children up to 2 years of age in resource-poor environments.

    PubMed

    2014-11-01

    Highly prevalent conditions with multiple and complex underlying etiologies are a challenge to public health. Undernutrition, for example, affects 20% of children in the developing world. The cause and consequence of poor nutrition are multifaceted. Undernutrition has been associated with half of all deaths worldwide in children aged <5 years; in addition, its pernicious long-term effects in early childhood have been associated with cognitive and physical growth deficits across multiple generations and have been thought to suppress immunity to further infections and to reduce the efficacy of childhood vaccines. The Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health (MAL-ED) Study, led by the Fogarty International Center of the National Institutes of Health and the Foundation for the National Institutes of Health, has been established at sites in 8 countries with historically high incidence of diarrheal disease and undernutrition. Central to the study is the hypothesis that enteropathogen infection contributes to undernutrition by causing intestinal inflammation and/or by altering intestinal barrier and absorptive function. It is further postulated that this leads to growth faltering and deficits in cognitive development. The effects of repeated enteric infection and undernutrition on the immune response to childhood vaccines is also being examined in the study. MAL-ED uses a prospective longitudinal design that offers a unique opportunity to directly address a complex system of exposures and health outcomes in the community-rather than the relatively rarer circumstances that lead to hospitalization-during the critical period of development of the first 2 years of life. Among the factors being evaluated are enteric infections (with or without diarrhea) and other illness indicators, micronutrient levels, diet, socioeconomic status, gut function, and the environment. MAL-ED aims to describe these

  19. Patient factors predict functional outcomes after cruciate retaining TKA: a 2-year follow-up analysis.

    PubMed

    Roth, Justin S; Buehler, Knute C; Shen, Jianhua; Naughton, Marybeth

    2013-09-01

    We analyzed preoperative patient characteristics and postoperative functional outcomes to identify the most predictive preoperative characteristics of postoperative functional outcome for Cruciate Retaining (CR) TKA. In a prospective, multicenter study, 307 knees with minimum 2-year follow-up were first divided into groups based on 2-year functional performance. Logistic regression then determined SF-36 General Health Score (GHS) to be the most predictive preoperative patient characteristic. Subsequently, a second analysis was performed using preoperative SF-36 GHS to stratify patients into groups. Statistical significance was achieved in both analyses by gender, BMI and hypertension. Statistical significance was achieved in a single analysis by age, preoperative narcotic use, preoperative metabolic medication usage, preoperative pulmonary disease and preoperative use of medication for anxiety or depression. PMID:23523205

  20. Tooth stain during 2 years' use of chlorhexidine- and fluoride-containing dentifrices.

    PubMed

    Dolles, O K; Eriksen, H M; Gjermo, P

    1979-08-01

    The purpose of the present study was to evaluate the effect of fluoride upon the stain-inducing capacity of chlorhexidine. Ninety-one children, 13 years of age, volunteered for the experiment. Three test dentifrices were used, containing 0.1% NaF, 0.1% NaF + 2% chlorhexidine, and 2% chlorhexidine respectively. The experiment was carried out as a double-blind test, and the degree of staining was recorded after 1 and 2 years. Four methods were used for stain scoring. The results after 1 year showed that chlorhexidine induced less stain when applied together with fluoride than when applied alone. After 2 years this difference disappeared, indicating that fluoride only retarded chlorhexidine-induced staining of teeth. PMID:295486

  1. A Study of Master's Degrees in Orchestral Conducting in the United States

    ERIC Educational Resources Information Center

    St. John, Brian Allen

    2010-01-01

    In order to learn to be an orchestra conductor in the United States of America, students often begins their formal education by seeking to earn a master's degree in orchestral conducting. This project compiled a listing of American universities which offer a master's degree in orchestral conducting and categorized the component parts of their…

  2. On the Feasibility of Conducting Randomised Trials in Education: Case Study of a Sex Education Intervention

    ERIC Educational Resources Information Center

    Moore, Laurence; Graham, Anna; Diamond, Ian

    2003-01-01

    This article reports on the conduct and results of a randomised controlled trial to test the effectiveness of a teacher-led intervention to improve teenagers' knowledge of emergency contraception. The trial was successfully conducted in 24 mixed-sex state secondary schools in Avon, South-west England. The intervention was popular with both…

  3. Study on Unit Cell Models and the Effective Thermal Conductivities of Silica Aerogel.

    PubMed

    Liu, He; Li, Zeng-Yao; Zhao, Xin-Peng; Tao, Wen-Quan

    2015-04-01

    In this paper, two modified unit cell models, truncated octahedron and cubic array of intersecting square rods with 45-degree rotation, are developed in consideration of the tortuous path of heat conduction in solid skeleton of silica aerogel. The heat conduction is analyzed for each model and the expressions of effective thermal conductivity of the modified unit cell models are derived. Considering the random microstructure of silica aerogel, the probability model is presented. We also discuss the effect of the thermal conductivity of aerogel backbone. The effective thermal conductivities calculated by the proposed probability model are in good agreement with available experimental data when the density of the aerogel is 110 kg/m3. PMID:26353566

  4. Patient satisfaction and penile morphology changes with postoperative penile rehabilitation 2 years after Coloplast Titan prosthesis.

    PubMed

    Pryor, Michael B; Carrion, Rafael; Wang, Run; Henry, Gerard

    2016-01-01

    A common complaint after inflatable penile prosthesis surgery is reduced penile length. We previously reported how using the Coloplast Titan inflatable penile prosthesis with aggressive new length measurement technique (NLMT) coupled with postoperative IPP rehabilitation of the implant for 1-year helped to improve patient satisfaction and erectile penile measurements. This is a 2 years follow-up of a prospective, three-center, study of 40 patients who underwent Titan prosthesis placement, with new length measurement technique for erectile dysfunction. Patient instructions were to inflate daily for 6 months and then inflate maximally for 1-2 h daily for 6-24 months. Fifteen penile measurements were taken before and immediately after surgery and at follow-up visits. Measurement changes were improved at 24 months as compared to immediately postoperative and at 12 months. 67.8% of subjects were satisfied with their length at 2 years, and 77% had perceived penile length that was longer (30.8%) or the same (46.2%) as prior to the surgery. 64.3% and 17.9% of subjects had increased and unchanged satisfaction, respectively, with penile length as compared to prior to penile implant surgery. All but one subject (96.5%) was satisfied with the overall function of his implant. This study suggests using the Coloplast Titan with aggressive cylinder sizing, and a postoperative penile rehabilitation inflation protocol can optimize patient satisfaction and erectile penile measurements at 2 years postimplant. PMID:26459782

  5. Patient satisfaction and penile morphology changes with postoperative penile rehabilitation 2 years after Coloplast Titan prosthesis

    PubMed Central

    Pryor, Michael B; Carrion, Rafael; Wang, Run; Henry, Gerard

    2016-01-01

    A common complaint after inflatable penile prosthesis surgery is reduced penile length. We previously reported how using the Coloplast Titan inflatable penile prosthesis with aggressive new length measurement technique (NLMT) coupled with postoperative IPP rehabilitation of the implant for 1-year helped to improve patient satisfaction and erectile penile measurements. This is a 2 years follow-up of a prospective, three-center, study of 40 patients who underwent Titan prosthesis placement, with new length measurement technique for erectile dysfunction. Patient instructions were to inflate daily for 6 months and then inflate maximally for 1–2 h daily for 6–24 months. Fifteen penile measurements were taken before and immediately after surgery and at follow-up visits. Measurement changes were improved at 24 months as compared to immediately postoperative and at 12 months. 67.8% of subjects were satisfied with their length at 2 years, and 77% had perceived penile length that was longer (30.8%) or the same (46.2%) as prior to the surgery. 64.3% and 17.9% of subjects had increased and unchanged satisfaction, respectively, with penile length as compared to prior to penile implant surgery. All but one subject (96.5%) was satisfied with the overall function of his implant. This study suggests using the Coloplast Titan with aggressive cylinder sizing, and a postoperative penile rehabilitation inflation protocol can optimize patient satisfaction and erectile penile measurements at 2 years postimplant. PMID:26459782

  6. Pial synangiosis in patients with moyamoya younger than 2 years of age.

    PubMed

    Jackson, Eric M; Lin, Ning; Manjila, Sunil; Scott, R Michael; Smith, Edward R

    2014-04-01

    Object Patients with moyamoya who are younger than 2 years of age represent a therapeutic challenge because of their frequent neurological instability and concomitant anesthetic risks. The authors report their experience with pial synangiosis revascularization in this population. Methods The authors reviewed the clinical and radiographic records of all patients with moyamoya in a consecutive series of patients under 2 years of age, who underwent cerebral revascularization surgery using pial synangiosis at a single institution. Results During a 12-year period (1994-2005), 34 procedures (bilateral in 15 patients, unilateral in 4) were performed in 19 patients younger than 2 years (out of a total of 456 procedures in 240 patients). Eighteen of these patients presented with either stroke or transient ischemic attack. The average age of the 19 patients at first surgery was 1.4 years (range 6 months-1.9 years). Unanticipated staged operations occurred in 3 patients, due to persistent electroencephalographic changes during the initial surgery in 2 cases and due to brain swelling during the procedure requiring ventriculostomy in the other. There were 2 perioperative strokes; both patients had postoperative seizures but made clinical recoveries. The average follow-up was 7 years (range 1-14 years). Long term, at follow-up, 13 patients (68%) were clinically independent for their age, with 8 (42%) having no significant deficit. Late complications included subdural hygroma evacuation (1), additional revascularization procedures performed years later for frontal lobe ischemia (2), late infarction (1), and asymptomatic ischemic change on routine follow-up MRI studies (1). All patients who had both pre- and postoperative angiography demonstrated progression of disease. Conclusions Despite the challenges inherent to this population, the majority of children with moyamoya under the age of 2 years have a good long-term prognosis. The data from this study support the use of pial

  7. Development and study of high-Tc superconductor conductive polymer assemblies

    NASA Astrophysics Data System (ADS)

    Schougaard, Steen Brian

    2002-01-01

    This dissertation presents the development and study of organic polymeric conductor/High-Tc superconductor bilayers, for exploration of the superconductor proximity effect. A major obstacle to this research is the instability of the High-Tc superconductor towards H2O and CO2 as it is necessary to create hybrid structures where the two conductors have intimate contact. For this reason, a study of the corrosion characteristics of the RBa2Cu3O 7 (R=Y, Eu, Nd) series was undertaken. In this study, R=Nd was shown to have enhanced corrosion resistance. In an effort to develop chemical processing methods that allow for the production of intimate contact between the cuprate superconductor and the conductive polymer systems, a study of alkyl amine adsorbed onto the surface of the superconductor is presented. In the electrochemical part of the study, alkyl amine ferrocene adsorbed onto the surface revealed that the amines are strongly adhered to the superconductor while still allowing electrons to pass from the superconductor to the ferrocene moiety. The self-assembled monolayer (SAM) structure of CF3(CF2)3(CH2) 11NH2 atop the superconductor was elucidated by employing several techniques, including atomic scale atomic force microscopy (AFM). A novel multistep bilayer sample preparation protocol is presented involving thin film fabrication by pulsed laser deposition (PLD), patterning by shadow mask ablation, sample thinning by scanning probe and electropolymerization of the polymer. Scanning probe thinning yields a smooth superconductor surface, a known superconductor thickness, and if a blocking layer is employed prior to thinning, the localization of polymer growth. Studies of the response of a bilayer structure of Y0.6Ca 0.4Ba1.6La0.4 Cu3O7/poly pyrrole to polymer redox cycling showed a semi-reversible suppression of transition temperature qualitatively consistent with a combination of corrosion and superconductor proximity effect. Quantitative analysis in the framework of

  8. 77 FR 60441 - Pediatric Studies of Sodium Nitroprusside Conducted in Accordance With Section 409I of the Public...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... data for this age group. On January 21, 2003, NIH published a Federal Register notice (68 FR 2789... HUMAN SERVICES Food and Drug Administration Pediatric Studies of Sodium Nitroprusside Conducted in... of sodium nitroprusside that were conducted in accordance with the Public Health Service Act (the...

  9. Conduct Disorder Symptoms and Subsequent Pregnancy, Child-Birth and Abortion: A Population-Based Longitudinal Study of Adolescents

    ERIC Educational Resources Information Center

    Pedersen, Willy; Mastekaasa, Arne

    2011-01-01

    Research on teenage pregnancy and abortion has primarily focused on socio-economic disadvantage. However, a few studies suggest that risk of unwanted pregnancy is related to conduct disorder symptoms. We examined the relationship between level of conduct disorder symptoms at age 15 and subsequent pregnancy, child-birth and abortion. A…

  10. Study of a guarded electrode system in the dc conductivity measurement of insulating liquid

    NASA Astrophysics Data System (ADS)

    Zhou, Yuan; Hao, Miao; Chen, George; Wilson, Gordon; Jarman, Paul

    2014-07-01

    The design and choice of an electrode system is important in dc conductivity measurement of insulating liquid. In this paper, the electric field distribution of an electrode system which consists of two parallel circular metallic electrodes and a guard electrode has been studied using Comsol Multiphysics software. A new parameter, which is not yet involved in current standards, the edge radius, has been mentioned in the literature formerly and is currently discussed in a CIGRE working group. In this paper, the influence of this parameter has been investigated by means of field calculation. As seen from the simulating result, there are regions in the vicinity of the edges of the guard and measuring electrode that are under high electric field. If the edges of these two electrodes are sharp, the maximum electric field in the test cell will be much higher than the average field between the measuring electrode and the high voltage electrode. An empirical equation has been proposed to calculate this maximum field. The classic correction expression for an effective radius has been re-evaluated with the edge radius being taken into account. Experimental work has been performed to confirm this conclusion. Three kinds of mineral oils with different ageing times have been tested under the dc field using a guarded electrode system and the electric strengths of these oils have been estimated. A recommendation has been made to current standards in insulating liquid measurement.

  11. A Unified Frequency Domain Model to Study the Effect of Demyelination on Axonal Conduction

    PubMed Central

    Chaubey, Saurabh; Goodwin, Shikha J.

    2016-01-01

    Multiple sclerosis is a disease caused by demyelination of nerve fibers. In order to determine the loss of signal with the percentage of demyelination, we need to develop models that can simulate this effect. Existing time-based models does not provide a method to determine the influences of demyelination based on simulation results. Our goal is to develop a system identification approach to generate a transfer function in the frequency domain. The idea is to create a unified modeling approach for neural action potential propagation along the length of an axon containing number of Nodes of Ranvier (N). A system identification approach has been used to identify a transfer function of the classical Hodgkin–Huxley equations for membrane voltage potential. Using this approach, we model cable properties and signal propagation along the length of the axon with N node myelination. MATLAB/Simulink platform is used to analyze an N node-myelinated neuronal axon. The ability to transfer function in the frequency domain will help reduce effort and will give a much more realistic feel when compared to the classical time-based approach. Once a transfer function is identified, the conduction as a cascade of each linear time invariant system-based transfer function can be modeled. Using this approach, future studies can model the loss of myelin in various parts of nervous system. PMID:27103847

  12. Risk factors for conduct disorder and delinquency: key findings from longitudinal studies.

    PubMed

    Murray, Joseph; Farrington, David P

    2010-10-01

    Conduct disorder (CD) and delinquency are behavioural problems involving violation of major rules, societal norms, and laws. The prevalence of CD and delinquency peaks in mid-to-late adolescence. Both show considerable continuity over time. The most important studies of CD and delinquency have prospective longitudinal designs, large community samples, repeated personal interviews, measures of many possible risk factors, and both self-reports and official measures of antisocial behaviour. The most important risk factors that predict CD and delinquency include impulsiveness, low IQ and low school achievement, poor parental supervision, punitive or erratic parental discipline, cold parental attitude, child physical abuse, parental conflict, disrupted families, antisocial parents, large family size, low family income, antisocial peers, high delinquency rate schools, and high crime neighbourhoods. However, for many risk factors, it is not known whether they have causal effects. Future research should examine changes in risk factors and changes in CD and delinquency to identify the risk factors that are causes and those that are merely markers of other risk mechanisms. PMID:20964942

  13. A Unified Frequency Domain Model to Study the Effect of Demyelination on Axonal Conduction.

    PubMed

    Chaubey, Saurabh; Goodwin, Shikha J

    2016-01-01

    Multiple sclerosis is a disease caused by demyelination of nerve fibers. In order to determine the loss of signal with the percentage of demyelination, we need to develop models that can simulate this effect. Existing time-based models does not provide a method to determine the influences of demyelination based on simulation results. Our goal is to develop a system identification approach to generate a transfer function in the frequency domain. The idea is to create a unified modeling approach for neural action potential propagation along the length of an axon containing number of Nodes of Ranvier (N). A system identification approach has been used to identify a transfer function of the classical Hodgkin-Huxley equations for membrane voltage potential. Using this approach, we model cable properties and signal propagation along the length of the axon with N node myelination. MATLAB/Simulink platform is used to analyze an N node-myelinated neuronal axon. The ability to transfer function in the frequency domain will help reduce effort and will give a much more realistic feel when compared to the classical time-based approach. Once a transfer function is identified, the conduction as a cascade of each linear time invariant system-based transfer function can be modeled. Using this approach, future studies can model the loss of myelin in various parts of nervous system. PMID:27103847

  14. Signs and Symptoms vs Nerve Conduction Studies to Diagnose Diabetic Sensorimotor Polyneuropathy

    PubMed Central

    2010-01-01

    Introduction Test whether physicians can validly and reproducibly diagnose diabetic sensorimotor polyneuropathy (DSPN). Methods Twelve physicians assessed 24 patients with diabetes mellitus (DM) on consecutive days (576 examinations) with physical features and voice disguised. Results were compared to gold standard 75% group diagnosis and a nerve conduction score (Σ 5 NC nds). Results Masking of patients was achieved. Reproducibility measured by the kappa coefficient and compared to Σ 5 NC nd varied considerably among physicians: median and ranges: signs 0.8 (0.32 to 1.0); symptoms 0.79 (0.36 to 1.0) and diagnoses 0.47 (0.33 to 0.84) – both low and high scores indicating poor performance. There was substantial agreement between 75% group dx and confirmed NC abnormality. As compared to Σ 5 NC, individual physicians’ clinical diagnosis was excessively variable and frequently inaccurate. Discussion Study physician diagnosis from signs and symptoms were excessively variable, often over-estimating DSPN. Specific approaches to improving proficiency should be tested. PMID:20658599

  15. Electrical conductivity studies on individual conjugated polymer nanowires: two-probe and four-probe results.

    PubMed

    Long, Yunze; Duvail, Jeanluc; Li, Mengmeng; Gu, Changzhi; Liu, Zongwen; Ringer, Simon P

    2009-01-01

    Two- and four-probe electrical measurements on individual conjugated polymer nanowires with different diameters ranging from 20 to 190 nm have been performed to study their conductivity and nanocontact resistance. The two-probe results reveal that all the measured polymer nanowires with different diameters are semiconducting. However, the four-probe results show that the measured polymer nanowires with diameters of 190, 95-100, 35-40 and 20-25 nm are lying in the insulating, critical, metallic and insulting regimes of metal-insulator transition, respectively. The 35-40 nm nanowire displays a metal-insulator transition at around 35 K. In addition, it was found that the nanocontact resistance is in the magnitude of 104Ω at room temperature, which is comparable to the intrinsic resistance of the nanowires. These results demonstrate that four-probe electrical measurement is necessary to explore the intrinsic electronic transport properties of isolated nanowires, especially in the case of metallic nanowires, because the metallic nature of the measured nanowires may be coved by the nanocontact resistance that cannot be excluded by a two-probe technique. PMID:20652139

  16. A genetically informative developmental study of the relationship between conduct disorder and peer deviance in males

    PubMed Central

    Kendler, K. S.; Jacobson, K.; Myers, J. M.; Eaves, L. J.

    2014-01-01

    Background Conduct disorder (CD) and peer deviance (PD) both powerfully predict future externalizing behaviors. Although levels of CD and PD are strongly correlated, the causal relationship between them has remained controversial and has not been examined by a genetically informative study. Method Levels of CD and PD were assessed in 746 adult male–male twin pairs at personal interview for ages 8–11, 12–14 and 15–17 years using a life history calendar. Model fitting was performed using the Mx program. Results The best-fit model indicated an active developmental relationship between CD and PD including forward transmission of both traits over time and strong causal relationships between CD and PD within time periods. The best-fit model indicated that the causal relationship for genetic risk factors was from CD to PD and was constant over time. For common environmental factors, the causal pathways ran from PD to CD and were stronger in earlier than later age periods. Conclusions A genetically informative model revealed causal pathways difficult to elucidate by other methods. Genes influence risk for CD, which, through social selection, impacts on the deviance of peers. Shared environment, through family and community processes, encourages or discourages adolescent deviant behavior, which, via social influence, alters risk for CD. Social influence is more important than social selection in childhood, but by late adolescence social selection becomes predominant. These findings have implications for prevention efforts for CD and associated externalizing disorders. PMID:17935643

  17. A multimodal mapping study of conduction aphasia with impaired repetition and spared reading aloud.

    PubMed

    Tomasino, Barbara; Marin, Dario; Maieron, Marta; D'Agostini, Serena; Medeossi, Irene; Fabbro, Franco; Skrap, Miran; Luzzatti, Claudio

    2015-04-01

    The present study explores the functional neuroanatomy of the phonological production system in an Italian aphasic patient (SP) who developed conduction aphasia of the reproduction type following brain surgery. SP presented with two peculiar features: (1) his lesion was localized in the superior temporal gyrus, just posterior to the primary auditory cortex and anterior/inferior to and neighboring the Sylvian parietal temporal (Spt) area, and (2) he presented with severely impaired repetition and spelling from dictation of words and pseudowords but spared reading-aloud of words and pseudowords. Structural, functional, fiber tracking and intraoperative findings were combined to analyze SP's pattern of performance within a widely used sensorimotor control scheme of speech production. We found a dissociation between an interrupted sector of the arcuate fasciculus terminating in STG, known to be involved in phonological processing, and a part of the arcuate fasciculus terminating in MTG, which is held to be involved in lexical-semantic processing. We argue that this phonological deficit should be interpreted as a disorder of the feedback system, in particular of the auditory and somatosensory target maps, which are assumed to be located along the Spt area. In patient SP, the spared part of the left arcuate fasciculus originating in MTG may support an unimpaired reading performance, while the damaged part of the left arcuate fasciculus originating in STG may be responsible for his impaired repetition and spelling from dictation. PMID:25701795

  18. DNA-conducting polymer complexes: a computational study of the hydrogen bond between building blocks.

    PubMed

    Zanuy, David; Aleman, Carlos

    2008-03-13

    Ab initio quantum mechanical calculations at the MP2 level were used for an extensive study concerning the stability of hydrogen-bonded complexes formed by pyrrole and thiophene, which are the most common building blocks of conducting polymers, and DNA bases. Results indicated that very stable complexes were formed with pyrrole, which shows a clear tendency to form specific hydrogen-bonding interactions with nucleic acid bases. Furthermore, the strength of such interactions depends significantly on the base, growing in the following order: thymine < adenine approximately equal to cytosine < guanine. On the contrary, thiophene formed complexes stabilized by nonspecific interactions between the pi-cloud of the ring and the N-H groups of the nucleic acid bases rather than specific hydrogen bonds. Overall, these results are fully consistent with experimental observations: polypyrrole is able not only to stabilize adducts with DNA but also to interact specifically, while the interactions of the latter with polythiophene and their derivatives are weaker and nonspecific. PMID:18278905

  19. Studies on high electronic energy deposition in transparent conducting indium tin oxide thin films

    NASA Astrophysics Data System (ADS)

    Deshpande, N. G.; Gudage, Y. G.; Ghosh, A.; Vyas, J. C.; Singh, F.; Tripathi, A.; Sharma, Ramphal

    2008-02-01

    We have examined the effect of swift heavy ions using 100 MeV Au8+ ions on the electrical properties of transparent, conducting indium tin oxide polycrystalline films with resistivity of 0.58 × 10-4 Ω cm and optical transmission greater than 78% (pristine). We report on the modifications occurring after high electronic energy deposition. With the increase in fluency, x-ray line intensity of the peaks corresponding to the planes (1 1 0), (4 0 0), (4 4 1) increased, while (3 3 1) remained constant. Surface morphological studies showed a pomegranate structure of pristine samples, which was highly disturbed with a high dose of irradiation. For the high dose, there was a formation of small spherical domes uniformly distributed over the entire surface. The transmittance was seen to be decreasing with the increase in ion fluency. At higher doses, the resistivity and photoluminescence intensity was seen to be decreased. In addition, the carrier concentration was seen to be increased, which was in accordance with the decrease in resistivity. The observed modifications after high electronic energy deposition in these films may lead to fruitful device applications.

  20. Numerical study of magnetoacoustic signal generation with magnetic induction based on inhomogeneous conductivity anisotropy.

    PubMed

    Li, Xun; Hu, Sanqing; Li, Lihua; Zhu, Shanan

    2013-01-01

    Magnetoacoustic tomography with magnetic induction (MAT-MI) is a noninvasive imaging modality for generating electrical conductivity images of biological tissues with high spatial resolution. In this paper, we create a numerical model, including a permanent magnet, a coil, and a two-layer coaxial cylinder with anisotropic electrical conductivities, for the MAT-MI forward problem. We analyze the MAT-MI sources in two cases, on a thin conductive boundary layer and in a homogeneous medium, and then develop a feasible numerical approach to solve the MAT-MI sound source densities in the anisotropic conductive model based on finite element analysis of electromagnetic field. Using the numerical finite element method, we then investigate the magnetoacoustic effect of anisotropic conductivity under the inhomogeneous static magnetic field and inhomogeneous magnetic field, quantitatively compute the boundary source densities in the conductive model, and calculate the sound pressure. The anisotropic conductivity contributes to the distribution of the eddy current density, Lorentz force density, and acoustic signal. The proposed models and approaches provide a more realistic simulation environment for MAT-MI. PMID:23606896