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Sample records for 90-day study reliability

  1. Subacute (90 days) oral toxicity studies of Kombucha tea.

    PubMed

    Vijayaraghavan, R; Singh, M; Rao, P V; Bhattacharya, R; Kumar, P; Sugendran, K; Kumar, O; Pant, S C; Singh, R

    2000-12-01

    Kombucha tea (KT) is a popular health beverage and is used as an alternative therapy. KT is prepared by placing the kombucha culture in solution of tea and sugar and allowing to ferment. The inoculum is a fungus consisting of symbiotic colony of yeast and bacteria. KT is consumed in several countries and is believed to have prophylactic and therapeutic benefits in a wide variety of ailments, viz., intestinal disorders, arthritis, ageing and stimulation of immunological system. Though KT is used in several parts of the world its beneficial effects and adverse effects have not been scientifically evaluated. Since there are no animal toxicological data on KT, subacute oral toxicity study was carried out. Five groups of rats were maintained: (a) control group given tap water orally, (b) KT given 2 ml/kg orally, (c) plain tea (PT) given 2 ml/kg orally, (d) KT given in drinking water, 1% (v/v) and (e) PT given in drinking water, 1% (v/v). The rats were given this treatment daily for a period of 90 days. Weekly records of weight, feed intake, water intake and general behaviour were monitored. There was no significant difference in the growth of the animals as evidenced by the progressive body weight change. The organ to body weight ratio and histological evaluation did not show any toxic signs. The haematological and biochemical variables were within the clinical limits. The study indicates that rats fed KT for 90 days showed no toxic effects.

  2. 90-Day Inhalation Toxicity Study of FT Fuel

    DTIC Science & Technology

    2011-08-01

    chromosome aberration test and micronucleus assay (Mattie et al., 2011a, 2011b), demonstrated that FT fuel was not mutagenic or genotoxic. The acute...over approximately 90 days, at concentrations of 0, 200, 700, and 2000 mg/m3. In the motor activity test , males exposed to the highest concentration...2 3.1 Test Substance ....................................................................................................................3 3.2

  3. The First 90 Days of the New Middle School Principal in a Turnaround School: In-Depth Case Study of the Transition Period (First 90 Days)

    ERIC Educational Resources Information Center

    Baeza, Marco A.

    2010-01-01

    This study analyzed skills, strategies, and theories that new middle school principals used to be successful during their transition period (the first 90 days) in turnaround schools. Based on research on transitions, three research questions guided the study: 1. Do middle school principals in a turnaround school situation find the transition…

  4. Safety assessment of meat from transgenic cattle by 90-day feeding study in rats.

    PubMed

    Liu, Shan; Li, Chen-Xi; Feng, Xiao-Lian; Wang, Hui-Ling; Liu, Hai-Bo; Zhi, Yuan; Geng, Gui-Ying; Zhao, Jie; Xu, Hai-Bin

    2013-07-01

    The study was carried out to evaluate the subchronic toxicity of meat derived from human lactoferrin gene-modified cattle in male and female Wistar rats. Rats were fed 5% or 10% transgenic meat diet, 5% or 10% conventional meat diet, or AIN93G diet for 90 days. During the study, body weight and food consumption were weighed weekly and clinical observations were conducted daily. At the end of the study, urinary examination, hematology and blood biochemistry examination, macroscopic and microscopic examinations were performed. There were no biologically significant differences in these factors between the rat groups fed transgenic meat diet and conventional meat diet. Therefore, the present 90-day rodent feeding study suggests that meat derived from the transgenic cattle is equivalent to meat from conventional cattle in use as dietary supplements.

  5. Preoperative risk score predicting 90-day mortality after liver resection in a population-based study.

    PubMed

    Chang, Chun-Ming; Yin, Wen-Yao; Su, Yu-Chieh; Wei, Chang-Kao; Lee, Cheng-Hung; Juang, Shiun-Yang; Chen, Yi-Ting; Chen, Jin-Cherng; Lee, Ching-Chih

    2014-09-01

    The impact of important preexisting comorbidities, such as liver and renal disease, on the outcome of liver resection remains unclear. Identification of patients at risk of mortality will aid in improving preoperative preparations. The purpose of this study is to develop and validate a population-based score based on available preoperative and predictable parameters predicting 90-day mortality after liver resection using data from a hepatitis endemic country.We identified 13,159 patients who underwent liver resection between 2002 and 2006 in the Taiwan National Health Insurance Research Database. In a randomly selected half of the total patients, multivariate logistic regression analysis was used to develop a prediction score for estimating the risk of 90-day mortality by patient demographics, preoperative liver disease and comorbidities, indication for surgery, and procedure type. The score was validated with the remaining half of the patients.Overall 90-day mortality was 3.9%. Predictive characteristics included in the model were age, preexisting cirrhosis-related complications, ischemic heart disease, heart failure, cerebrovascular disease, renal disease, malignancy, and procedure type. Four risk groups were stratified by mortality scores of 1.1%, 2.2%, 7.7%, and 15%. Preexisting renal disease and cirrhosis-related complications were the strongest predictors. The score discriminated well in both the derivation and validation sets with c-statistics of 0.75 and 0.75, respectively.This population-based score could identify patients at risk of 90-day mortality before liver resection. Preexisting renal disease and cirrhosis-related complications had the strongest influence on mortality. This score enables preoperative risk stratification, decision-making, quality assessment, and counseling for individual patients.

  6. Multisite Study of an Implanted Continuous Glucose Sensor Over 90 Days in Patients With Diabetes Mellitus

    PubMed Central

    Dehennis, Andrew; Mortellaro, Mark A.; Ioacara, Sorin

    2015-01-01

    Background: Continuous glucose monitoring (CGM), which enables real-time glucose display and trend information as well as real-time alarms, can improve glycemic control and quality of life in patients with diabetes mellitus. Previous reports have described strategies to extend the useable lifetime of a single sensor from 1-2 weeks to 28 days. The present multisite study describes the characterization of a sensing platform achieving 90 days of continuous use for a single, fully implanted sensor. Method: The Senseonics CGM system is composed of a long-term implantable glucose sensor and a wearable smart transmitter. Study subjects underwent subcutaneous implantation of sensors in the upper arm. Eight-hour clinic sessions were performed every 14 days, during which sensor glucose values were compared against venous blood lab reference measurements collected every 15 minutes using mean absolute relative differences (MARDs). Results: All subjects (mean ± standard deviation age: 43.5 ± 11.0 years; with 10 sensors inserted in men and 14 in women) had type 1 diabetes mellitus. Most (22 of 24) sensors reported glucose values for the entire 90 days. The MARD value was 11.4 ± 2.7% (range, 8.1-19.5%) for reference glucose values between 40-400 mg/dl. There was no significant difference in MARD throughout the 90-day study (P = .31). No serious adverse events were noted. Conclusions: The Senseonics CGM, composed of an implantable sensor, external smart transmitter, and smartphone app, is the first system that uses a single sensor for continuous display of accurate glucose values for 3 months. PMID:26224762

  7. Human exploration of space: A review of NASA's 90-day study and alternatives

    NASA Technical Reports Server (NTRS)

    Stever, H. Guyford; Cannon, Robert H., Jr.; Gavin, Joseph G.; Kerrebrock, Jack L.; Lanzerotti, Louis J.; Levinthal, Elliott C.; Mar, James W.; Mcelroy, John H.; Mcruer, Duane T.; Merrell, William J., Jr.

    1990-01-01

    The National Research Council (NRC) examines the NASA Report of the 90-Day Study on Human Exploration of the Moon and Mars, and alternative concepts. Included in this paper, prepared for the National Space Council, are the answers to a challenging set of questions posed by the Vice President. Concerns addressed include: the appropriate pace, the scope of human exploration, the level of long-term support required, the technology development available and needed, the feasibility of long-duration human spaceflight in a low-gravity environment, scientific objectives, and other considerations such as costs and risks.

  8. Safety assessment of vitacoxib: Acute and 90-day sub-chronic oral toxicity studies.

    PubMed

    Wang, Jianzhong; Sun, Feifei; Tang, Shusheng; Zhang, Suxia; Lv, Pengyue; Li, Jing; Cao, Xingyuan

    2017-02-24

    Vitacoxib, is a newly developed coxibs NSAID (selective inhibitors of cyclooxygenase-2). To date, no experimental data have been published concerning its safety for use as an additive in the human diet. In the present study, we assessed the acute and sub-chronic toxicity of vitacoxib administered by gavage. The acute toxicity tests in Sprague Dawley (SD) rats and ICR mice demonstrated that vitacoxib at a dose of 5000 mg/kg BW failed to alter any of the parameters studied. In the 90-day sub-chronic toxicity test, vitacoxib was administered to SD rats at the doses of 0 (control), 5, 10, 20, 30, and 60 mg/kg BW. The results demonstrated that there were no significant differences for most indexes of sub-chronic toxicity throughout the experiment at the dose of 5-20 mg/kg BW, indicating no apparent dose-dependent. However, there were significant histopathology changes in the liver and kidney, and alterations in some biochemical parameters in the 60 mg/kg BW group. Based on these findings, the gavage LD50 was determined to be > 5000 mg/kg in SD rats and ICR mice, and the 90-day gavage no-observed-adverse-effect level (NOAEL) of vitacoxib was considered to be 20 mg/kg BW under the present study conditions.

  9. A 90-day toxicity study of GmTMT transgenic maize in Sprague-Dawley rats.

    PubMed

    Fang, Jin; Feng, Yongquan; Zhi, Yuan; Zhang, Lan; Yu, Zhou; Jia, Xudong

    2017-04-01

    GmTMT transgenic maize is a genetically modified maize plant that overexpresses the γ-tocopherol methyltransferase (γ-TMT) from Glycine max (Gm). The γ-TMT gene was introduced into maize line Zhen58 to encode the GmTMT2a protein which can convert γ-tocopherol into α-tocopherol. Overexpression of GmTMT2a significantly increased the α-tocopherol content in transgenic maize. The present study was designed to investigate any potential effects of GmTMT maize grain in a 90-day subchronic rodent feeding study. Maize grains from GmTMT or Zhen58 were incorporated into rodent diets at low (12.5%), medium (25%) or high (50%) concentrations and administered to Sprague-Dawley rats (n = 10/sex/group) for 90 days. The negative control group of rats (n = 10/sex/group) were fed with common maize diets. Results from body weights, feed consumption, clinical chemistry, hematology, absolute and relative organ weights indicated no treatment-related side effects of GmTMT maize grain on rats in comparison with rats consuming diets containing Zhen58 maize grain. In addition, no treatment-related changes were found in necropsy and histopathology examinations. Altogether, our data indicates that GmTMT transgenic maize is as safe and nutritious as its conventional non-transgenic maize.

  10. A subchronic 90-day oral toxicity study of Origanum vulgare essential oil in rats.

    PubMed

    Llana-Ruiz-Cabello, M; Maisanaba, S; Puerto, M; Pichardo, S; Jos, A; Moyano, R; Cameán, A M

    2017-03-01

    Oregano essential oil (Origanum vulgare L. virens) (OEO) is being used in the food industry due to its useful properties to develop new active packaging systems. In this concern, the safety assessment of this natural extract is of great interest before being commercialized. The European Food Safety Authority requests different in vivo assays to ensure the safety of food contact materials. One of these studies is a 90 days repeated-dose oral assay in rodents. In the present work, 40 male and 40 female Wistar rats were orally exposed to 50, 100 and 200 mg/kg body weight (b.w.) OEO during 90 days following the OECD guideline 408. Data revealed no mortality and no treatment-related adverse effects of the OEO in food/water consumption, body weight, haematology, biochemistry, necropsy, organ weight and histopathology. These findings suggest that the oral no-observed-adverse-effect level (NOAEL) of this OEO is 200 mg/kg b.w. in Wistar rats, the highest dose tested. In conclusion, the use of this OEO in food packaging appears to be safe based on the lack of toxicity during the subchronic study at doses 330-fold higher than those expected to be in contact consumers in the worst scenario of exposure.

  11. A 90 day chronic toxicity study of Nigerian herbal preparation DAS-77 in rats

    PubMed Central

    2012-01-01

    Background The herbal preparation DAS-77, used for the treatment of various ailments in Nigeria, contains the milled bark of Mangifera indica L. and root of Carica papaya L. Toxicological assessment of the preparation was carried out in this study. Methods In the acute toxicity study, DAS-77 was administered to mice p.o. up to 20 g/kg in divided doses and i.p. at 250–3000 mg/kg. Mortality within 24 h was recorded. In the chronic toxicity study, rats were treated p.o. for 90 days at doses of 80, 400 (therapeutic dose, TD) and 2000 mg/kg. By 90 days, animals were sacrificed and blood samples collected for hematological and biochemical analysis. Organs were harvested for weight determination, antioxidants and histopathological assessments. Results DAS-77 did not produce any lethality administered p.o. up to 20 g/kg in divided doses but the i.p. LD50 was 1122.0 mg/kg. At TD, DAS-77 produced significant (p < 0.05) reductions in body weight, food intake and K+, and increases in ovary weight, neutrophils and HDL, which were reversible. Histopathological presentations were generally normal. Effects at the other doses were comparable to those at TD except for reversible increases in antioxidants in the liver, kidney and testes, and sperm abnormality, and reductions in liver enzymes, sperm motility and count. Conclusions Findings in this study revealed that DAS-77 is relatively safe with the potential for enhancing in vivo antioxidant activity. However, possibly reversible side-effects include electrolyte imbalance and sterility in males. PMID:22892317

  12. A 90-Day Feeding Study in Rats to Assess the Safety of Genetically Engineered Pork.

    PubMed

    Xiao, Gao-Jun; Jiang, Sheng-Wang; Qian, Li-Li; Cai, Chun-Bo; Wang, Qing-Qing; Ma, De-Zun; Li, Biao; Xie, Shan-Shan; Cui, Wen-Tao; Li, Kui

    2016-01-01

    Our laboratory recently produced genetically engineered (GE) Meishan pigs containing a ZFN-edited myostatin loss-of-function mutant. These GE pigs develop and grow as normal as wild type pigs but produce pork with greater lean yield and lower fat mass. To assess any potential subchronic toxicity risks of this GE pork, a 90-day feeding study was conducted in Sprague-Dawley rats. Rats were randomly divided into five groups, and fed for 90 days with basic diet and basic diets formulated with low dose and high dose pork prepared from wild type pigs and GE pigs, respectively. Animal behaviors and clinical signs were monitored twice daily, and body weight and food consumption were measured and recorded weekly. At days 45 and 90, blood tests (lipid panel, electrolytes, parameters related to liver and kidney functions, and complete blood counts) were performed. Additionally, gross pathology and histopathological analyses were performed for major organs in each group. Data analysis shows that there were no significant differences in growth rate, food consumption, and blood test parameters between rat groups fed with GE pork and wild type pork. Although differences in some liver function parameters (such as aspartate aminotransferase, total proteins, albumin, and alkaline phosphatase) and white blood cell counts (such as lymphocyte percentage and monocyte percentage) were observed between rats fed with high dose GE pork and basic diet, all test results in rats fed with GE pork are in the normal range. Additionally, there are no apparent lesions noted in all organs isolated from rats in all five feeding groups on days 45 and 90. Overall, our results clearly indicate that food consumption of GE pork produced by ZFN-edited myostatin loss-of-function mutant pigs did not have any long-term adverse effects on the health status in rats.

  13. A 90-Day Feeding Study in Rats to Assess the Safety of Genetically Engineered Pork

    PubMed Central

    Xiao, Gao-jun; Jiang, Sheng-Wang; Qian, Li-Li; Cai, Chun-Bo; Wang, Qing-qing; Ma, De-Zun; Li, Biao; Xie, Shan-shan; Cui, Wen-Tao; Li, Kui

    2016-01-01

    Our laboratory recently produced genetically engineered (GE) Meishan pigs containing a ZFN-edited myostatin loss-of-function mutant. These GE pigs develop and grow as normal as wild type pigs but produce pork with greater lean yield and lower fat mass. To assess any potential subchronic toxicity risks of this GE pork, a 90-day feeding study was conducted in Sprague-Dawley rats. Rats were randomly divided into five groups, and fed for 90 days with basic diet and basic diets formulated with low dose and high dose pork prepared from wild type pigs and GE pigs, respectively. Animal behaviors and clinical signs were monitored twice daily, and body weight and food consumption were measured and recorded weekly. At days 45 and 90, blood tests (lipid panel, electrolytes, parameters related to liver and kidney functions, and complete blood counts) were performed. Additionally, gross pathology and histopathological analyses were performed for major organs in each group. Data analysis shows that there were no significant differences in growth rate, food consumption, and blood test parameters between rat groups fed with GE pork and wild type pork. Although differences in some liver function parameters (such as aspartate aminotransferase, total proteins, albumin, and alkaline phosphatase) and white blood cell counts (such as lymphocyte percentage and monocyte percentage) were observed between rats fed with high dose GE pork and basic diet, all test results in rats fed with GE pork are in the normal range. Additionally, there are no apparent lesions noted in all organs isolated from rats in all five feeding groups on days 45 and 90. Overall, our results clearly indicate that food consumption of GE pork produced by ZFN-edited myostatin loss-of-function mutant pigs did not have any long-term adverse effects on the health status in rats. PMID:27812153

  14. Safety assessment of dietary bamboo charcoal powder: a 90-day subchronic oral toxicity and mutagenicity studies.

    PubMed

    Zhenchao, Jia; Yuting, Zhong; Jiuming, Yan; Yedan, Lu; Yang, Song; Jinyao, Chen; Lishi, Zhang

    2015-01-01

    Vegetable carbon has been used as food additive in EU (E153) and China for many years; however, no experimental data have been available on its dietary safety. This study was designed to evaluate the subchronic toxicity and genotoxicity of bamboo charcoal powder (BCP). In the study of subchronic oral toxicity, BCP was administered orally at doses of 2.81, 5.62, and 11.24 g/kg BW for 90 days to SD rats. Additional satellite groups from the control group and high dose group were observed for a 28-day recovery period. At the end of the treatment and recovery periods, animals were sacrificed, and their organs were weighed and blood samples were collected. The toxicological endpoints observed included clinical signs, food consumption, body and organ weights, hematological and biochemical parameters, macroscopic and microscopic examinations. The results showed no significant differences between the BCP treated groups and control group. The genotoxicity of BCP was assessed with the Salmonella typhimurium mutagenicity assay (Ames test) and a combination of comet assay and mammalian erythrocyte micronucleus protocol. The results did not reveal any genotoxicity of BCP. Based on our study, the no-observed-adverse-effect level (NOAEL) for BCP is 11.24 g/kg BW/day.

  15. 90-day dietary toxicity study with esterified propoxylated glycerol (EPG) in micropigs.

    PubMed

    Wedig, John; Bechtel, David H

    2014-12-01

    The subchronic (90-day) toxicity of esterified propoxylated glycerol (EPG) was assessed in micropigs. Animals (5/sex/group) received feed containing 5%, 10%, and 17% EPG, mixed accordingly throughout the study to deliver 1.5, 3, and 5 g/kg bw/day of EPG, respectively. Corn oil served as the vehicle control (0 g/kg bw/day). Subsets of animals were evaluated at Week 6; the remainder between Weeks 12 and 14. With the exception of liver and serum vitamin levels, statistically significant difference between control and EPG groups were seen sporadically, and with no apparent connection to treatment and/or no consistency across time intervals. EPG intakes of 3 and 5 g/kg bw/day, but not at 1.5 g/kg bw/day were associated with significantly lower serum 25-OH vitamin D levels. Serum total vitamin D levels were significantly lower across all EPG groups. There were also trends toward lower levels of liver vitamins A and E among EPG-treated animals, but the effects were less consistent. The effects on vitamin levels observed in EPG-treated animals were not accompanied by any signs of vitamin deficiency (e.g., effects on growth, clinical signs, or clinical pathology), and might have been related to the larger mass of EPG acting as a lipid "sink" during transit in the gastrointestinal tract.

  16. A 90-day subchronic toxicity study of neem oil, a Azadirachta indica oil, in mice.

    PubMed

    Wang, C; Cao, M; Shi, D-X; Yin, Z-Q; Jia, R-Y; Wang, K-Y; Geng, Y; Wang, Y; Yao, X-P; Yang, Z-R; Zhao, J

    2013-09-01

    To determine the no-observed-adverse-effect level (NOAEL) of exposure and target organs of neem oil for establishing safety criteria for human exposure, the subchronic toxicity study with neem oil in mice was evaluated. The mice (10 per sex for each dose) was orally administered with neem oil with the doses of 0 (to serve as a control), 177, 533 and 1600 mg/kg/day for 90 days. After the treatment period, observation of reversibility or persistence of any toxic effects, mice were continuously fed without treatment for the following 30 days. During the two test periods, the serum biochemistry, organ weight and histopathology were examined. The results showed that the serum biochemistry and organ coefficient in experimental groups had no statistical difference compared with those of the control group. At the 90th day, the histopathological examinations showed that the 1600 mg/kg/day dose of neem oil had varying degrees of damage on each organ except heart, uterus and ovarian. After 30-day recovery, the degree of lesions to the tissues was lessened or even restored. The NOAEL of neem oil was 177 mg/kg/day for mice and the target organs of neem oil were determined to be testicle, liver and kidneys.

  17. Trichloromelamine 14-Day Range Finding and 90-Day Subchronic Studies in Rats. 3 August 1988 - 17 January 1989. Phase 2

    DTIC Science & Technology

    1992-11-13

    COSATI CODES 10. SUBJECT TERMS (Continue on reverne if necessary and identify by block number) FIELD GROUP SUB-GROUP Trichloroemelamine, toxicity , 14-Day...90-Day 19, ABSTRACT (Conamnue on revers if necessary and identify by block number) The subchronic study examined the toxicity of the food service...observed adverse effect level in the 90-day study was 30 mg/kg/day. Trichloromelamine should be considered moderately toxic when ingested acutely

  18. [Kooroo color: 90-day dietary toxicity study in F344 rats].

    PubMed

    Sekita, Kiyoshi; Umemura, Takashi; Saito, Minoru; Ogawa, Yukio; Ueno, Katsunori; Kaneko, Toyozo; Uchida, Osayuki; Matsushima, Yuko; Kawasaki, Yasushi; Inoue, Tohru

    2002-06-01

    A subchronic toxicity study on kooroo color was conducted using F344 rats of both genders. Kooroo color is an extract of yam root, Dioscorea matudai Hayata, of which the major components are known to be flavonoid pigments. Use of kooroo as a food color is permitted by the Food Sanitation Law in Japan, but the chronic toxicity has not been evaluated in the literature. Rats were fed the product of kooroo color (PKC) at doses of 0.5%, 1.50%, and 5.0% in basal powder diet, while control groups received PKC-free basal diet, for ninety days. A vehicle control given propylene glycol (PG) alone, at the same dosage that the 5.0% group received, was included, because PKC used in this study contained ca. 80 percent PG, used as an extractant during the manufacturing processes. Daily observation of general behavior, and weekly measurement of body weight as well as food consumption were performed. Hematological, serum biochemical and anatomopathological examinations were conducted at the end of administration. No abnormalities ascribable to the treatment with PKC or PG were noted in any examination in this study. Hence, dietary intake of 5.0% of PKC, i.e., 2,993 mg/kg/day for males, and 3,376 mg/kg/day for females, as a mean daily intake for 90 days, had no observable adverse effect in F344 rats. Therefore, kooroo color has no significant general toxicity, and its toxicity, if any, is of a very low order.

  19. Zinc oxide nanoparticles: a 90-day repeated-dose dermal toxicity study in rats

    PubMed Central

    Ryu, Hwa Jung; Seo, Mu Yeb; Jung, Sung Kyu; Maeng, Eun Ho; Lee, Seung-Young; Jang, Dong-Hyouk; Lee, Taek-Jin; Jo, Ki-Yeon; Kim, Yu-Ri; Cho, Kyu-Bong; Kim, Meyoung-Kon; Lee, Beom Jun; Son, Sang Wook

    2014-01-01

    Zinc oxide (ZnO) works as a long-lasting, broad-spectrum physical sunblock, and can prevent skin cancer, sunburn, and photoaging. Nanosized ZnO particles are used often in sunscreens due to consumer preference over larger sizes, which appear opaque when dermally applied. Although the US Food and Drug Administration approved the use of nanoparticles (NPs) in sunscreens in 1999, there are ongoing safety concerns. The aim of this study was to evaluate the subchronic toxicity of ZnO NPs after dermal application according to the Organization for Economic Cooperation and Development Test Guidelines 411 using Good Laboratory Practice. Sprague Dawley rats were randomly divided into eight (one control, one vehicle control, three experimental, and three recovery) groups. Different concentrations of ZnO NPs were dermally applied to the rats in the experimental groups for 90 days. Clinical observations as well as weight and food consumption were measured and recorded daily. Hematology and biochemistry parameters were determined. Gross pathologic and histopathologic examinations were performed on selected tissues from all animals. Analyses of tissue were undertaken to determine target organ tissue distribution. There was no increased mortality in the experimental group. Although there was dose-dependent irritation at the site of application, there were no abnormal findings related to ZnO NPs in other organs. Increased concentrations of ZnO in the liver, small intestine, large intestine, and feces were thought to result from oral ingestion of ZnO NPs via licking. Penetration of ZnO NPs through the skin seemed to be limited via the dermal route. This study demonstrates that there was no observed adverse effect of ZnO NPs up to 1,000 mg/kg body weight when they are applied dermally. PMID:25565832

  20. A repeated dose 90-day oral toxicity study of cyflumetofen,a novel acaricide, in rats.

    PubMed

    Yoshida, Toshinori; Ikemi, Naoki; Takeuchi, Yukiko; Ebino, Koichi; Kojima, Sayuri; Chiba, Yuko; Nakashima, Nobuaki; Kawakatsu, Hisao; Saka, Machiko; Harada, Takanori

    2012-02-01

    Cyflumetofen is a novel acaricide which is highly active against phytophagous mites. As a part of safety assessment, a repeated dose 90-day oral toxicity study of cyflumetofen was conducted in Fischer (F344/DuCrj) rats of both sexes. Technical grade cyflumetofen was administered in feed to groups of 10 males and 10 females at dose levels of 0, 100, 300, 1,000, and 3,000 ppm. Prothrombin time was prolonged in males at 3,000 ppm and plasma globulin levels were decreased in females at 1,000 and 3,000 ppm. At necropsy, enlarged and whitish adrenals were observed in females at 3,000 ppm. There were statistically significant increases in relative liver weight (ratio to body weight) in males and relative adrenal weight in females in the 1,000 ppm group; increased relative liver and kidney weights in both sexes at 3,000 ppm, and increased absolute and relative weights of adrenals in females at 3,000 ppm. Increased absolute liver weight was also noted in males at 3,000 ppm. Histopathologically, at 1,000 and 3,000 ppm males had diffuse vacuolation and females had diffuse hypertrophy of adrenal cortical cells. In addition, vacuolation of ovarian interstitial gland cells was noted in females at 1,000 and 3,000 ppm. There were no treatment-related changes in any parameters for either sex in other dose groups. Based on these results, the no-observed-adverse-effect level (NOAEL) of cyflumetofen was judged to be 300 ppm for both sexes (16.5 mg/kg/day for males and 19.0 mg/kg/day for females).

  1. Range Finding 14-Day and 90-Day Subchronic Feeding Studies with N,N-Dipropylcyclohexanecarboxamide in Rats. Phase 4.

    DTIC Science & Technology

    1986-12-01

    clinical chemistry values. Significant increases occurred in male rat liver organ-to-body weight ratios in all three dose levels at the 45 and 90 day necropsies during the 90-day feeding study. A no effect dose was not achieved during this study. Additional testing would be required to confirm a no effect dose level. It is concluded that a toxic hazard may exist from a prolonged significant oral exposure to N,N-Dopropylcyclohexanecarboxamide. It is recommended that further evaluation of this compound as a candidate insect repellent be discontinued due to the deleterious

  2. A 90-Day Oral Toxicity Study and a 5-Day Metabolism Study of Diisopropyl Methylphosphonate (DIMP) in Mink.

    DTIC Science & Technology

    1992-06-01

    Eighty 12-13 month-old brown "Ranch Wild " mink of each sex were randomized by body weight into eight dose groups of ten animals per sex. The animals...Laboratory Practice Standard (Toxic Substances Control Act) was followed. 90-DAY STUDY One hundred sixty 12-13 month-old brown "Ranch Wild " mink (80...3.2 x 10ŚM sec-’ * Hydrolysis Half- life : 687 years * Decomposition Products: (in microwave plasma discharge): methylphosphonic acid, isopropyl

  3. 90-Day Cycle Handbook

    ERIC Educational Resources Information Center

    Park, Sandra; Takahashi, Sola

    2013-01-01

    90-Day Cycles are a disciplined and structured form of inquiry designed to produce and test knowledge syntheses, prototyped processes, or products in support of improvement work. With any type of activity, organizations inevitably encounter roadblocks to improving performance and outcomes. These barriers might include intractable problems at…

  4. Report of the 90-day study on human exploration of the Moon and Mars

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The basic mission sequence to achieve the President's goal is clear: begin with Space Station Freedom in the 1990's, return to the Moon to stay early in the Next century, and then journey to Mars. Five reference approaches are modeled building on past programs and recent studies to reflect wide-ranging strategies that incorporate varied program objectives, schedules, technologies, and resource availabilities. The reference approaches are (1) balance and speed; (2) the earliest possible landing on Mars; (3) reduce logistics from Earth; (4) schedule adapted to Space Station Freedom; and (5) reduced scales. The study and programmatic assessment have shown that the Human Exploration Initiative is indeed a feasible approach to achieving the President's goals. Several reasonable alternatives exist, but a long-range commitment and significant resources will be required. However, the value of the program and the benefits to the Nation are immeasurable.

  5. Toxicological assessment of a prototype e-cigaret device and three flavor formulations: a 90-day inhalation study in rats

    PubMed Central

    Werley, Michael S.; Kirkpatrick, Dan J.; Oldham, Michael J.; Jerome, Ann M.; Langston, Timothy B.; Lilly, Patrick D.; Smith, Donna C.; Mckinney, Willie J.

    2016-01-01

    Abstract A prototype electronic cigaret device and three formulations were evaluated in a 90-day rat inhalation study followed by a 42-day recovery period. Animals were randomly assigned to groups for exposure to low-, mid- and high-dose levels of aerosols composed of vehicle (glycerin and propylene glycol mixture); vehicle and 2.0% nicotine; or vehicle, 2.0% nicotine and flavor mixture. Daily targeted aerosol total particulate matter (TPM) doses of 3.2, 9.6 and 32.0 mg/kg/day were achieved by exposure to 1 mg/L aerosol for 16, 48 and 160 min, respectively. Pre-study evaluations included indirect ophthalmoscopy, virology and bacteriological screening. Body weights, clinical observations and food consumption were monitored weekly. Plasma nicotine and cotinine and carboxyhemoglobin levels were measured at days 28 and 90. After days 28, 56 and 90, lung function measurements were obtained. Biological endpoints after 90-day exposure and 42-day recovery period included clinical pathology, urinalysis, bronchoalveolar fluid (BALF) analysis, necropsy and histopathology. Treatment-related effects following 90 days of exposure included changes in body weight, food consumption and respiratory rate. Dose-related decreases in thymus and spleen weights, and increased BALF lactate dehydrogenase, total protein, alveolar macrophages, neutrophils and lung weights were observed. Histopathology evaluations revealed sporadic increases in nasal section 1–4 epithelial hyperplasia and vacuolization. Following the recovery period, effects in the nose and BALF were persistent while other effects were resolved. The no observed effect level based upon body weight decreases is considered to be the mid-dose level for each formulation, equivalent to a daily TPM exposure dose of approximately 9.6 mg/kg/day. PMID:26787428

  6. Safety assessment of essential oil from Minthostachys verticillata (Griseb.) Epling (peperina): 90-days oral subchronic toxicity study in rats.

    PubMed

    Escobar, Franco Matías; Sabini, María Carola; Cariddi, Laura Noelia; Sabini, Liliana Inés; Mañas, Fernando; Cristofolini, Andrea; Bagnis, Guillermo; Gallucci, Mauro Nicolas; Cavaglieri, Lilia Renée

    2015-02-01

    Minthostachys verticillata (Lamiaceae), popularly known as peperina is largely used in popular medicine for its digestive, carminative, antispasmodic and antirheumatic properties. There are no reports of repeated exposure toxicity to guarantee their safety. The present study investigated the chemical composition, analyzed by GC-FID, and the 90-day toxicity and genotoxicity effect of M. verticillata essential oil (Mv-EO), using Wistar rats as test animals. The rats were divided into four groups (5 rats/sex/group) and Mv-EO was administered on diet at doses of 0, 1, 4 and 7 g/kg feed. The main components of Mv-EO were pulegone (64.65%) and menthone (23.92%). There was no mortality, adverse effects on general conditions or changes in body weight, food consumption and feed conversion efficiency throughout the study in male and female rats. Subchronic administration of Mv-EO did not alter the weights, morphological and histopathological analyses of liver, kidney and intestine. Genotoxicity was tested by micronucleus and comet assays. Mv-EO up to a concentration of 7 g/kg feed for 90 days did not exert a cyto-genotoxic effect on the bone marrow and cells blood of Wistar rats. These results suggest that Mv-EO appears to be safe and could be devoid of any toxic risk.

  7. A 90-day subchronic toxicity study with sodium formononetin-3'-sulphonate (Sul-F) delivered to dogs via intravenous administration.

    PubMed

    Li, Chunmei; Li, Guisheng; Gao, Yonglin; Sun, Chengfeng; Wang, Xiaoyan

    2016-06-01

    Sodium formononetin-3'-sulphonate (Sul-F) is a water-soluble derivate of formononetin, and an increasing number of studies have shown that Sul-F not only possesses favorable water solubility but also exhibits good lipid-lowering and bioactivities. In the current study, the toxicity of Sul-F was evaluated in dogs after 90-day intravenous infusion. Dogs were treated with Sul-F at dose of 0, 33.3, 100, and 300 mg/kg, and observed for 90-day followed by 28-day recovery period. Weekly measurement of body weight, temperature and food consumption were conducted. Ophthalmoscopy, ECG examination, urinalysis, serum biochemistry and hematology examination were performed at pre-test, on days 45 and 90, and following by 28-day recovery period. Histological examination was performed on day 90 and 28-day recovery period. No mortality, ophthalmic abnormalities or treatment-related findings in body weight, clinical chemistry, hematology, and histopathological examination were detected. However, a white crystal (non-metabolic Sul-F), transient vomiting and recoverable vascular stimulation were observed in 300 mg/kg/day Sul-F treated dogs. Under the conditions, the no-observed-adverse-effect-level (NOAEL) for Sul-F was 100 mg/kg in dogs.

  8. A 90-day oral (dietary) toxicity and mass balance study of corn starch fiber in Sprague Dawley rats.

    PubMed

    Crincoli, Christine M; Nikiforov, Andrey I; Rihner, Marisa O; Lambert, Elizabeth A; Greeley, Melanie A; Godsey, Justin; Eapen, Alex K; van de Ligt, Jennifer L G

    2016-11-01

    The potential toxicity of corn starch fiber was assessed and compared to polydextrose, a commonly used bulking agent with a long history of safe use in the food supply. Groups of male and female Crl:CD(SD) rats were fed 0 (control), 1,000, 3,000, or 10,000 mg/kg-bw/day corn starch fiber in the diet for 90 days. The polydextrose reference article was offered on a comparable regimen at 10,000 mg/kg-bw/day. Following a single gavage dose of [(14)C]-corn starch fiber on study day 13 or 90, the mass balance of the test article was assessed by analysis of excreta samples collected from 0 to 168 h post-dose. There were no toxicologically or biologically relevant findings in any of the test article-treated groups. The few minor differences observed between the corn starch fiber and polydextrose exposed groups were considered to be due to normal biological variation. Following [(14)C]-corn starch fiber dosing, nearly complete excretion of the administered dose occurred over 168 h post-dosing, with the majority excreted in the feces. The dietary no-observed-adverse-effect level of corn starch fiber after 90 days was 10,000 mg/kg-bw/day. Similar toxicity profiles for corn starch fiber and polydextrose were observed due to the structural and compositional similarities of these materials.

  9. A 90-day study of three bruchid-resistant mung bean cultivars in Sprague-Dawley rats.

    PubMed

    Yao, Yang; Cheng, Xuzhen; Ren, Guixing

    2015-02-01

    Mung bean has been traditionally and widely used as an edible and medicinal plant in the South and Southeast Asia. Bruchid resistance mung bean has more potential in commercial use, but scarcely been evaluated for safety through standard in vivo toxicological studies. In the present study, subchronic oral toxicity studies of bruchid-resistant mung bean were designed and conducted in Sprague-Dawley (SD) rats for 90 days. During the subchronic oral toxicity study, no mortality and toxicologically significant changes in clinical signs, food consumption, opthalmoscopic examination, hematology, clinical biochemistry, macroscopic findings, organ weights and histopathological examination were noted in animal administered diet containing bruchid-resistant mung bean. These results demonstrated that bruchid resistant mung bean is as safe as conventional mung bean.

  10. A 90-day toxicology study of meat from genetically modified sheep overexpressing TLR4 in Sprague-Dawley rats.

    PubMed

    Bai, Hai; Wang, Zhixian; Hu, Rui; Kan, Tongtong; Li, Yan; Zhang, Xiaosheng; Zhang, Jinlong; Lian, Ling; Han, Hongbing; Lian, Zhengxing

    2015-01-01

    Genetic modification offers alternative strategies to traditional animal breeding. However, the food safety of genetically modified (GM) animals has attracted increasing levels of concern. In this study, we produced GM sheep overexpressing TLR4, and the transgene-positive offsprings (F1) were confirmed using the polymerase chain reaction (PCR) and Southern blot. The expression of TLR4 was 2.5-fold compared with that of the wild-type (WT) sheep samples. During the 90-day safety study, Sprague-Dawley rats were fed with three different dietary concentrations (3.75%, 7.5%, and 15% wt/wt) of GM sheep meat, WT sheep meat or a commercial diet (CD). Blood samples from the rats were collected and analyzed for hematological and biochemical parameters, and then compared with hematological and biochemical reference ranges. Despite a few significant differences among the three groups in some parameters, all other values remained within the normal reference intervals and thus were not considered to be affected by the treatment. No adverse diet-related differences in body weights or relative organ weights were observed. Furthermore, no differences were observed in the gross necropsy findings or microscopic pathology of the rats whose diets contained the GM sheep meat compared with rats whose diets contained the WT sheep meat. Therefore, the present 90-day rat feeding study suggested that the meat of GM sheep overexpressing TLR4 had no adverse effect on Sprague-Dawley rats in comparison with WT sheep meat. These results provide valuable information regarding the safety assessment of meat derived from GM animals.

  11. Results of a 90-day safety assurance study with rats fed grain from corn rootworm-protected corn.

    PubMed

    Hammond, B; Lemen, J; Dudek, R; Ward, D; Jiang, C; Nemeth, M; Burns, J

    2006-02-01

    The results of a 90-day rat feeding study with YieldGard (YieldGard Rootworm Corn is a registered trademark of Monsanto Technology, LLC.) Rootworm corn (MON 863) grain that is protected against feeding damage caused by corn rootworm larvae are presented. Corn rootworm-protection was accomplished through the introduction of a cry3Bb1 coding sequence into the corn genome for in planta production of a modified Cry3Bb1 protein from Bacillus thuringiensis. Grain from MON 863 and its near isogenic control were separately formulated into rodent diets at levels of 11% and 33% (w/w) by Purina Mills, Inc. Additionally, six groups of rats were fed diets containing grain from different conventional (non-biotechnology-derived) reference varieties. The responses of rats fed diets containing MON 863 were compared to those of rats fed grain from conventional corn varieties. All diets were nutritionally balanced and conformed to Purina Mills, Inc. specifications for Certified LabDiet 5002. There were a total of 400 rats in the study divided into 10 groups of 20 rats/sex/group. Overall health, body weight gain, food consumption, clinical pathology parameters (hematology, blood chemistry, urinalysis), organ weights, gross and microscopic appearance of tissues were comparable between groups fed diets containing MON 863 and conventional corn varieties. This study complements extensive agronomic, compositional and farm animal feeding studies with MON 863 grain, confirming that it is as safe and nutritious as existing conventional corn varieties.

  12. Results of a 90-day safety assurance study with rats fed grain from corn borer-protected corn.

    PubMed

    Hammond, B G; Dudek, R; Lemen, J K; Nemeth, M A

    2006-07-01

    The results of a 90-day rat feeding study with grain from MON 810 corn (YieldGard Cornborer -- YieldGard Cornborer is a registered trademark of Monsanto Technology, LLC) that is protected against feeding damage from corn and stalk boring lepidopteran insects are presented. Corn borer protection was accomplished through the introduction of cry1Ab coding sequences into the corn genome for in planta production of a bioactive form of Cry1Ab protein. Grain from MON 810 and its near-isogenic control was separately formulated into rodent diets at levels of 11% and 33% (w/w) by Purina Mills, Inc. (PMI). All diets were nutritionally balanced and conformed to PMI specifications for Certified LabDiet (PMI Certified LabDiet 5002 is a registered trademark of Purina Mills, Inc.) 5002. There were a total of 400 rats in the study divided into 10 groups of 20 rats/sex/group. The responses of rats fed diets containing MON 810 were compared to those of rats fed grain from conventional corn varieties. Overall health, body weight, food consumption, clinical pathology parameters (hematology, blood chemistry, urinalysis), organ weights, and gross and microscopic appearance of tissues were comparable between groups fed diets containing MON 810 and conventional corn varieties. This study complements extensive agronomic, compositional and farm animal feeding studies with MON 810 grain, confirming that it is as safe and nutritious as grain from existing commercial corn varieties.

  13. Safety assessment of genetically modified milk containing human beta-defensin-3 on rats by a 90-day feeding study.

    PubMed

    Chen, Xin; Gao, Ming-Qing; Liang, Dong; Yin, Songna; Yao, Kezhen; Zhang, Yong

    2017-02-01

    In recent years, transgenic technology has been widely applied in many fields. There is concern about the safety of genetically modified (GM) products with the increased prevalence of GM products. In order to prevent mastitis in dairy cows, our group produced transgenic cattle expressing human beta-defensin-3 (HBD3) in their mammary glands, which confers resistance to the bacteria that cause mastitis. The milk derived from these transgenic cattle thus contained HBD3. The objective of the present study was to analyze the nutritional composition of HBD3 milk and conduct a 90-day feeding study on rats. Rats were divided into 5 groups which consumed either an AIN93G diet (growth purified diet for rodents recommended by the American Institute of Nutrition) with the addition of 10% or 30% HBD3 milk, an AIN93G diet with the addition of 10% or 30% conventional milk, or an AIN93G diet alone. The results showed that there was no difference in the nutritional composition of HBD3 and conventional milk. Furthermore, body weight, food consumption, blood biochemistry, relative organ weight, and histopathology were normal in those rats that consumed diets containing HBD3. No adverse effects were observed between groups that could be attributed to varying diets or gender.

  14. A 90-day subchronic feeding study of genetically modified rice expressing Cry1Ab protein in Sprague-Dawley rats.

    PubMed

    Song, Huan; He, Xiaoyun; Zou, Shiying; Zhang, Teng; Luo, Yunbo; Huang, Kunlun; Zhu, Zhen; Xu, Wentao

    2015-04-01

    Bacillus thuringiensis (Bt) transgenic rice line (mfb-MH86) expressing a synthetic cry1Ab gene can be protected against feeding damage from Lepidopteran insects, including Sesamia inferens, Chilo suppressalis, Tryporyza incertulas and Cnaphalocrocis medinalis. Rice flour from mfb-MH86 and its near-isogenic control MH86 was separately formulated into rodent diets at concentrations of 17.5, 35 and 70 % (w/w) for a 90-day feeding test with rats, and all of the diets were nutritionally balanced. In this study, the responses of rats fed diets containing mfb-MH86 were compared to those of rats fed flour from MH86. Overall health, body weight and food consumption were comparable between groups fed diets containing mfb-MH86 and MH86. Blood samples were collected prior to sacrifice and a few significant differences (p < 0.05) were observed in haematological and biochemical parameters between rats fed genetically modified (GM) and non-GM diets. However, the values of these parameters were within the normal ranges of values for rats of this age and sex, thus not considered treatment related. In addition, upon sacrifice a large number of organs were weighed, macroscopic and histopathological examinations were performed with only minor changes to report. In conclusion, these results demonstrated that no toxic effect was observed in the conditions of the experiment, based on the different parameters assessed. GM rice mfb-MH86 is as safe and nutritious as non-GM rice.

  15. Calf venous volume during stand-test after a 90-day bed-rest study with or without exercise countermeasure

    PubMed Central

    de Chantemèle, Eric Belin; Pascaud, Ludovic; Custaud, Marc-Antoine; Capri, Arnaud; Louisy, Francis; Ferretti, Guido; Gharib, Claude; Arbeille, Philippe

    2004-01-01

    The objectives to determine both the contribution to orthostatic intolerance (OI) of calf venous volume during a stand-test, and the effects of a combined eccentric–concentric resistance exercise countermeasure on both vein response to orthostatic test and OI, after 90-day head-down tilt bed-rest (HDT). The subjects consisted of a control group (Co-gr, n = 9) and an exercise countermeasure group (CM-gr, n = 9). Calf volume and vein cross-sectional area (CSA) were assessed by plethysmography and echography during pre- and post-HDT stand-tests. From supine to standing (post-HDT), the tibial and gastronemius vein CSA increased significantly in intolerant subjects (tibial vein, +122% from pre-HDT; gastronemius veins, +145%; P < 0.05) whereas it did not in tolerant subjects. Intolerant subjects tended to have a higher increase in calf filling volume than tolerant subjects, in both sitting and standing positions. The countermeasure did not reduce OI. Absolute calf volume decreased similarly in both groups. Tibial and gastrocnemius vein CSA at rest did not change during HDT in either group. During the post-HDT stand-test, the calf filling volume increased more in the CM-gr than in the Co-gr both in the sitting (+1.3 ± 5.1%, vs.–7.3 ± 4.3%; P < 0.05) and the standing positions (+56.1 ± 23.7%vs.+1.6 ± 9.6%; P < 0.05). The volume ejected by the muscle venous pump increased only in the CM-gr (+38.3 ± 21.8%). This study showed that intolerant subjects had a higher increase in vein CSA in the standing position and a tendency to present a higher calf filling volume in the sitting and standing positions. It also showed that a combined eccentric–concentric resistance exercise countermeasure had no effects on either post-HDT OI or on the venous parameters related to it. PMID:15331681

  16. Toxicity studies on agent GA (Phase 2): 90 day subchronic study of GA (Tabun) in cd rats. Appendices. Final report, July 1985-August 1991

    SciTech Connect

    Not Available

    1992-03-01

    The purpose of the report is to provide essential toxicologic information on Tabun administration over a 90 day period. This toxicologic information may be used to adjust the maximum-tolerated dose for subsequent dominant-lethal and two-generation reproduction studies. The objectives were to determine the toxic effects of nerve agent exposure (e.g., target organs); and to determine the effects of nerve agent GA on sperm morphology and motility and vaginal cytology.

  17. A 90-day safety study in Sprague-Dawley rats fed milk powder containing recombinant human lactoferrin (rhLF) derived from transgenic cloned cattle.

    PubMed

    Zhou, Cui; Wang, Jian Wu; Huang, Kun Lun; He, XiaoYun; Chen, Xiu Ping; Sun, Hong; Yu, Tian; Che, Hui Lian

    2011-10-01

    Transgenic cloned animals expressing beneficial human nutritional traits offer a new strategy for large-scale production of some kinds of functional substances. In some cases, the required safety testing for genetically modified (GM) foods do not seem appropriate for human food safety, though regulations do not seem to provide alternatives. A 90-day rat feeding study is the core study for the safety assessment of GM foods. The test material in this 90-day study was prepared nonfat milk powder containing recombinant human lactoferrin (rhLF), which was expressed in transgenic cloned cattle. Groups of 10 male and female Sprague-Dawley rats were given a nutritionally balanced purified diet containing 7.5, 15, or 30% transgenic or conventional milk powder for 90 days. A commercial AIN93G diet was used as an additional control group. Clinical, biological, and pathological parameters were compared between groups. The only significant effect of treatment was higher mean ferritin and Fe(+) concentrations for both male and female rats fed the transgenic milk powder diets, as compared to rats fed nontransgenic milk diets or the commercial diet. The results of the present study are consistent with previous research, which indicates that milk powder containing rhLF derived from healthy transgenic cloned cattle is as safe as conventional milk powder.

  18. A 90-day safety study of genetically modified rice expressing rhIGF-1 protein in C57BL/6J rats.

    PubMed

    Tang, Maoxue; Xie, Tingting; Cheng, Wenke; Qian, Lili; Yang, Shulin; Yang, Daichang; Cui, Wentao; Li, Kui

    2012-06-01

    Genetically modified plants expressing disease resistance traits offer new treatment strategies for human diseases, but at the same time present a challenge in terms of food safety assessment. The present 90-day feeding study was designed to assess the safety of transgenic rice expressing the recombinant human insulin-like growth factor-1 (rhIGF-1) compared to its parental wild rice. Male and female C57BL/6J rats were given a nutritionally balanced purified diet with 20% transgenic rhIGF-1 rice or 20% parental rice for 90 days. This corresponds to a mean daily rhIGF-1 protein intake of approximately 217.6 mg/kg body weight based on the average feed consumption. In the animal study a range of biological, biochemical, clinical, microbiological and pathological parameters were examined and several significant differences were observed between groups, but none of the effects were considered to be adverse. In conclusion, no adverse or toxic effects on C57BL/6J rats were observed in the design used in this 90-day study. These results will provide valuable information for the safety assessment of genetically modified food crops.

  19. Vitamin D deficiency at admission is not associated with 90-day mortality in patients with severe sepsis or septic shock: Observational FINNAKI cohort study.

    PubMed

    Ala-Kokko, Tero I; Mutt, Shivaprakash J; Nisula, Sara; Koskenkari, Juha; Liisanantti, Janne; Ohtonen, Pasi; Poukkanen, Meri; Laurila, Jouko J; Pettilä, Ville; Herzig, Karl-Heinz

    2016-01-01

    Introduction Low levels of vitamin D have been associated with increased mortality in patients that are critically ill. This study explored whether vitamin D levels were associated with 90-day mortality in severe sepsis or septic shock. Methods Plasma vitamin D levels were measured on admission to the intensive care unit (ICU) in a prospective multicentre observational study. Results 610 patients with severe sepsis were included; of these, 178 (29%) had septic shock. Vitamin D deficiency (<50 nmol/L) was present in 333 (55%) patients. The 90-day mortality did not differ among patients with or without vitamin D deficiency (28.3% vs. 28.5%, p = 0.789). Diabetes was more common among patients deficient compared to those not deficient in vitamin D (30% vs. 18%, p < 0.001). Hospital-acquired infections at admission were more prevalent in patients with a vitamin D deficiency (31% vs. 16%, p < 0.001). A multivariable adjusted Cox regression model showed that low vitamin D levels could not predict 90-day mortality (<50 nmol/L: hazard ratio (HR) 0.99 (95% CI: 0.72-1.36), p > 0.9; and <25 nmol/L: HR 0.44 (95% CI: 0.22-0.87), p = 0.018). Conclusions Vitamin D deficiency detected upon ICU admission was not associated with 90-day mortality in patients with severe sepsis or septic shock. Key messages In severe sepsis and septic shock, a vitamin D deficiency upon ICU admission was not associated with increased mortality. Compared to patients with sufficient vitamin D, patients with deficient vitamin D more frequently exhibited diabetes, elevated C-reactive protein levels, and hospital-acquired infections upon ICU admission, and they more frequently developed acute kidney injury.

  20. Safety assessment of the fermented Phylloporia ribis (Lonicera japonica Thunb.) mycelia by oral acute toxicity study in mice and 90-day feeding study in rats.

    PubMed

    Lu, Lianhua; Fan, Yiou; Yao, Wenhuan; Xie, Wei; Guo, Jie; Yan, Yan; Yang, Fei; Xu, Lingchuan

    2014-07-01

    Phylloporia ribis is an edible fungus in China. Its fermented mycelia have been approved by the National Health and Family Planning Commission (NHFPC) of PR China for use as a novel food material, but little information on its safety is available. The present research was the first to evaluate acute and subchronic toxicity in experimental animals of fermented Phylloporia ribis mycelia (FPM) following standard procedures. In acute toxicity study, FPM was orally administered to male and female mice twice a day at single dose of 10 g/kg bw. The Maximum Tolerated Dose (MTD) of FPM for mice of both sexes was over 10 g/kg bw. No death and abnormal behaviors occurred during 14 days study except for an increased locomotor activity in three animals. In 90-day feeding study, male and female Sprague-Dawley rats were fed diets containing 10.0%, 5.0%, 2.5%, 1.25% and 0% (control) FPM for 90 days. The treatment caused no effects on mortality, gross pathology, histology, hematology, and blood chemistry, no dose-dependent changes in food consumption, but caused effect on body weight gain compared with control group. The No Observed Adverse-Effect Level (NOAEL) of FPM was greater than 8.7 g/kg bw/day in both sexes of rats.

  1. Comparative safety testing of genetically modified foods in a 90-day rat feeding study design allowing the distinction between primary and secondary effects of the new genetic event.

    PubMed

    Knudsen, Ib; Poulsen, Morten

    2007-10-01

    This article discusses the wider experiences regarding the usefulness of the 90-day rat feeding study for the testing of whole foods from genetically modified (GM) plant based on data from a recent EU-project [Poulsen, M., Schrøder, M., Wilcks, A., Kroghsbo, S., Lindecrona, R.H., Miller, A., Frenzel, T., Danier, J., Rychlik, M., Shu, Q., Emami, K., Taylor, M., Gatehouse, A., Engel, K.-H., Knudsen, I., 2007a. Safety testing of GM-rice expressing PHA-E lectin using a new animal test design. Food Chem. Toxicol. 45, 364-377; Poulsen, M., Kroghsbo, S., Schrøder, M., Wilcks, A., Jacobsen, H., Miller, A., Frenzel, T., Danier, J., Rychlik, M., Shu, Q., Emami, K., Sudhakar, D., Gatehouse, A., Engel, K.-H., Knudsen, I., 2007b. A 90-day safety in Wistar rats fed genetically modified rice expressing snowdrop lectin Galanthus nivalis (GNA). Food Chem. Toxicol. 45, 350-363; Schrøder, M., Poulsen, M., Wilcks, A., Kroghsbo, S., Miller, A., Frenzel, T., Danier, J., Rychlik, M., Emami, K., Gatehouse, A., Shu, Q., Engel, K.-H., Knudsen, I., 2007. A 90-day safety study of genetically modified rice expressing Cry1Ab protein (Bacillus thuringiensis toxin) in Wistar rats. Food Chem. Toxicol. 45, 339-349]. The overall objective of the project has been to develop and validate the scientific methodology necessary for assessing the safety of foods from genetically modified plants in accordance with the present EU regulation. The safety assessment in the project is combining the results of the 90-day rat feeding study on the GM food with and without spiking with the pure novel gene product, with the knowledge about the identity of the genetic change, the compositional data of the GM food, the results from in-vitro/ex-vivo studies as well as the results from the preceding 28-day toxicity study with the novel gene product, before the hazard characterisation is concluded. The results demonstrated the ability of the 90-day rat feeding study to detect the biological/toxicological effects of the

  2. A 90-day subchronic feeding study of genetically modified maize expressing Cry1Ac-M protein in Sprague-Dawley rats.

    PubMed

    Liu, Pengfei; He, Xiaoyun; Chen, Delong; Luo, Yunbo; Cao, Sishuo; Song, Huan; Liu, Ting; Huang, Kunlun; Xu, Wentao

    2012-09-01

    The cry1Ac-M gene, coding one of Bacillus thuringiensis (Bt) crystal proteins, was introduced into maize H99 × Hi IIB genome to produce insect-resistant GM maize BT-38. The food safety assessment of the BT-38 maize was conducted in Sprague-Dawley rats by a 90-days feeding study. We incorporated maize grains from BT-38 and H99 × Hi IIB into rodent diets at three concentrations (12.5%, 25%, 50%) and administered to Sprague-Dawley rats (n=10/sex/group) for 90 days. A commercialized rodent diet was fed to an additional group as control group. Body weight, feed consumption and toxicological response variables were measured, and gross as well as microscopic pathology were examined. Moreover, detection of residual Cry1Ac-M protein in the serum of rats fed with GM maize was conducted. No death or adverse effects were observed in the current feeding study. No adverse differences in the values of the response variables were observed between rats that consumed diets containing GM maize BT-38 and non-GM maize H99 × Hi IIB. No detectable Cry1Ac-M protein was found in the serum of rats after feeding diets containing GM maize for 3 months. The results demonstrated that BT-38 maize is as safe as conventional non-GM maize.

  3. Safety assessment of SDA soybean oil: results of a 28-day gavage study and a 90-day/one generation reproduction feeding study in rats.

    PubMed

    Hammond, Bruce G; Lemen, Joan K; Ahmed, Gulam; Miller, Kathleen D; Kirkpatrick, Jeannie; Fleeman, Tammye

    2008-12-01

    Long chain polyunsaturated fatty acids (LC-PUFAs) in the diet reduce risk of cardiac mortality. Fish oils are a dietary source of LC-PUFAs (EPA, DHA) but intake is low in Western diets. Adding beneficial amounts of LC-PUFAs to foods is limited by their instability and potential to impart off-flavors. Stearidonic acid (SDA), a precursor of EPA in man, is more stable than EPA/DHA in food matrices. SDA is present in fish oils (0.5-4%) and in nutraceuticals (echium, borage oil). Genes for Delta6, Delta15 desaturases were introduced into soybeans that convert linoleic and alpha-linolenic acid to SDA (15-30% fatty acids). Since addition of SDA soybean oil into human foods increases SDA intake, toxicology studies were undertaken to assess its safety. In a 28-day pilot study, rats were gavaged with SDA soybean oil at dosages up to 3g/kg body weight/day; no treatment-related adverse effects were observed. A 90-day/one generation rat reproduction study was subsequently conducted where SDA soybean oil was added to diets to provide daily doses of 1.5 and 4 g/kg body weight. There were no treatment-related adverse effects on parental animals or on reproductive performance and progeny development.

  4. Metabonomics study of transgenic Bacillus thuringiensis rice (T2A-1) meal in a 90-day dietary toxicity study in rats.

    PubMed

    Cao, Sishuo; Xu, Wentao; Luo, YunBo; He, Xiaoyun; Yuan, Yanfang; Ran, Wenjun; Liang, Lixing; Huang, Kunlun

    2011-07-01

    Rice is one of the most important staple foods in the world. The Cry2A gene was inserted into the rice genome to help the plant combat insects. As the unintended effects of the genetically modified (GM) organisms are the most important barriers to the promotion of GM organisms, we have carried out a useful exploration to establish a new in vivo evaluation model for genetically modified foods by metabonomics methods. In this study, the rats were fed for 90 days with the GM and NON-GM rice diets. The changes in metabolites of the urine were detected using (1)H-NMR. The metabonomics were analyzed to see whether the GM rice can induce the metabolite changes in the rats' urine when compared with the NON-GM rice group. The multivariate analysis and ANOVA were used to determine the differences and the significance of differences respectively, and eventually we concluded that these differences did not have a biological significance. The conclusion of the metabonomics was comparable with that from the traditional method. As a non-invasive and dynamic monitoring method, metabonomics will be a new way of assessing the food safety of GM foods.

  5. Toxicity studies on Agents GB and GD (Phase 2): 90-day subchronic study of GB (Sarin, Type II) in CD rats. Final report, Jul 85-Aug 91

    SciTech Connect

    Bucci, T.J.; Parker, R.M.

    1992-01-01

    A two-phase Dose Range findng study and a 90-Day Subchronic study were conducted in CD rats using the organophosphate ester Sarin (Agent GB, Type II, CAS Number 107-44-8). The highest dose level without lethality in the second phase of the range finding study was designated the maximum tolerated dose (MTD). The doses selected for the subchronic study were the MTD (300 micron GBII/Kg/day), MTD/2 (150micron GBII/Kg/day), MTD/4 (75micron GBII/Kg/day), and a vehicle control . Forty-eight male and forty-eight female CD rats were randomly allocated at 11 -1 2 weeks of age into four treatment groups (1 2 per sex per group). The animals were gavaged Monday through Friday for 13 weeks and euthanized with carbon dioxide at the beginning of the fourteenth week. Animals were observed daily for clinical signs of toxicity and were weighed weekly. The rats were bled (6 rat/sex/dose) during weeks -1, 1, 3, 7, and at necropsy. Necropsy examination was performed on all animals. Microscopic evaluation was performed on all high-dose and control animals and on those tissues of lower dose animals that were abnormal at necropsy. All gross lesions and all animals dying or removed early received histological examination. A cause of death or morbidity for animals removed before the end of the study, determined from histopathological examination, was established in four cases. There were several statistically significant effects in the clinical chemistry and hematology data. These effects were scattered among the treatment groups and were not numerous enough to develop a pattern of organ toxicity.

  6. Toxicity studies on Agents GB and GD (Phase 2): 90-day subchronic study of GB (Sarin, Type I) in CD rats. Final report, Jul 85-Aug 91

    SciTech Connect

    Bucci, T.J.; Parker, R.M.; Crowell, J.A.; Thurman, J.D.; Gosnell, P.A.

    1991-08-01

    A two-phase Dose Range finding study and a 90-Day Subchronic study were conducted in CD rats using the organophosphate ester Sarin (Agent GB, Type I, CAS Number 107-44-8). The highest dose level without lethality in the second phase of the range finding study was designated the maximum tolerated dose (MTD). The doses selected for the subchronic study were the MTD (300 micron GBI/Kg/day), MTD/2 (150, micron GBI/Kg/day), MTD/4 (75 micron GBI/Kg/day), and a vehicle control (O micron /Kg/day). Forty-eight male and forty-eight female CD rats were randomly allocated at 11-12 weeks of age into four treatment groups (12 per sex per group). The animals were gavaged Monday through Friday for 13 weeks and euthanized with carbon dioxide at the beginning of the fourteenth week. Animals were observed daily for clinical signs of toxicity and were weighed weekly. The rats were bled (6 rats/sex/dose) during weeks -1, 1, 3, 7, and at necropsy. Necropsy examination was performed on all animals. Microscopic evaluation was performed on all high-dose and control animals, and on those tissues of lower dose animals that were abnormal at necropsy. All gross lesions and all animals dying or removed early received histological examination. A cause of death or morbidity for animals removed before the end of the study, determined from histopathological examination, was established in four of the eight cases. There were several statistically significant effects in the clinical chemistry and hematology data. These effects were scattered among the treatment groups and were not numerous enough to develop a pattern of organ toxicity.

  7. A 90-day study of sub-chronic oral toxicity of 20 nm positively charged zinc oxide nanoparticles in Sprague Dawley rats

    PubMed Central

    Park, Hark-Soo; Kim, Seon-Ju; Lee, Taek-Jin; Kim, Geon-Yong; Meang, EunHo; Hong, Jeong-Sup; Kim, Su-Hyon; Koh, Sang-Bum; Hong, Seung-Guk; Sun, Yle-Shik; Kang, Jin Seok; Kim, Yu-Ri; Kim, Meyoung-Kon; Jeong, Jayoung; Lee, Jong-Kwon; Son, Woo-Chan; Park, Jae-Hak

    2014-01-01

    Purpose The study reported here was conducted to determine the systemic oral toxicity and to find the no-observed-adverse-effect level of 20 nm positively charged zinc oxide (ZnOSM20(+)) nanoparticles in Sprague Dawley rats for 90 days. Methods For the 90-day toxicity study, the high dose was set as 500 mg per kg of body weight (mg/kg) and the middle and low dose were set to 250 mg/kg and 125 mg/kg, respectively. The rats were held for a 14-day recovery period after the last administration, to observe for the persistence or reduction of any toxic effects. A distributional study was also carried out for the systemic distribution of ZnOSM20(+) NPs. Results No rats died during the test period. There were no significant clinical changes due to the test article during the experimental period in functional assessment, body weight, food and water consumption, ophthalmological testing, urine analysis, necropsy findings, or organ weights, but salivation was observed immediately after administration in both sexes. The total red blood cell count was increased, and hematocrit, albumin, mean cell volume, mean cell hemoglobin, and mean cell hemoglobin concentration were decreased significantly compared with control in both 500 mg/kg groups. Total protein and albumin levels were decreased significantly in both sexes in the 250 and 500 mg/kg groups. Histopathological studies revealed acinar cell apoptosis in the pancreas, inflammation and edema in stomach mucosa, and retinal atrophy of the eye in the 500 mg/kg group. Conclusion There were significant parameter changes in terms of anemia in the hematological and blood chemical analyses in the 250 and 500 mg/kg groups. The significant toxic change was observed to be below 125 mg/kg, so the no-observed-adverse-effect level was not determined, but the lowest-observed-adverse-effect level was considered to be 125 mg/kg in both sexes and the target organs were found to be the pancreas, eye, and stomach. PMID:25565829

  8. Phase II, Randomized, Placebo-controlled, 90-day Study of Emixustat HCL in Geographic Atrophy Associated with Dry Age-Related Macular Degeneration

    PubMed Central

    Dugel, Pravin U.; Novack, Roger L.; Csaky, Karl G.; Richmond, Preston P.; Birch, David G.; Kubota, Ryo

    2015-01-01

    Purpose This study assessed the safety, tolerability, and pharmacodynamics of emixustat hydrochloride (ACU-4429), a novel visual cycle modulator, in subjects with geographic atrophy (GA) associated with dry age-related macular degeneration (AMD). Methods Subjects were randomly assigned to oral emixustat (2, 5, 7, or 10 mg once daily) or placebo (3:1 ratio) for 90 days. Recovery of rod photoreceptor sensitivity following a photobleach was measured by electroretinography. Safety evaluations included analysis of adverse events (AEs) and ophthalmic examinations. Results Seventy-two subjects (54 emixustat, 18 placebo) were evaluated. Emixustat suppressed rod photoreceptor sensitivity in a dose-dependent manner. Suppression plateaued by Day 14, and was reversible within 7-14 days after drug cessation. No systemic AEs of concern were noted. Dose-related ocular AEs (chromatopsia, 57% emixustat vs. 17% placebo; and delayed dark adaptation, 48% emixustat vs. 6% placebo) were mild to moderate, and the majority resolved on study or within 7-14 days after study drug cessation. Conclusions In this phase II study, emixustat produced a dose-dependent, reversible effect on rod function, and an ocular AE profile that is consistent with the proposed mechanism of action. These results support further testing of emixustat for the treatment of GA associated with dry AMD. PMID:25932553

  9. Compositional and toxicological analysis of a GM potato line with reduced α-solanine content--a 90-day feeding study in the Syrian Golden hamster.

    PubMed

    Langkilde, Søren; Schrøder, Malene; Frank, Thomas; Shepherd, Louise V T; Conner, Sean; Davies, Howard V; Meyer, Otto; Danier, Jürgen; Rychlik, Michael; Belknap, William R; McCue, Kent F; Engel, Karl-Heinz; Stewart, Derek; Knudsen, Ib; Poulsen, Morten

    2012-10-01

    Steroidal glycoalkaloids (GAs) are toxins, produced by plants of the Solanaceae family. The potato plant (Solanum tuberosum L.) and its tubers predominantly contain the two GAs α-chaconine and α-solanine. These compounds are believed to act in synergy, and the degree of toxicity may therefore depend on their ratio in the potato. To determine the influence of α-solanine: α-chaconine ratio in potatoes on toxicity, a GM potato line (SGT 9-2) with reduced α-solanine content, and the parental control line (Desirée wild-type) having a traditional α-solanine: α-chaconine ratio were (1) studied for compositional similarity by analysing for a range of potato constituents, and (2) used in a 90-day feeding trial with the Syrian Golden hamster to study differential toxicity. The animal feeding study used diets with up to 60% freeze-dried potato powder from either line. Whilst data indicated some compositional differences between the GM line and its wildtype control these did not raise concerns related to nutritional value or safety. Results of the feeding trials showed a low number of significant differences between potato lines with different α-solanine: α-chaconine ratio but none were considered to raise safety concerns with regard to human (or animal) consumption.

  10. Results of a 90-day toxicity study on 1,2,3- and 1,1,2-trichloropropane administered via the drinking water.

    PubMed

    Villeneuve, D C; Chu, I; Secours, V E; Coté, M G; Plaa, G L; Valli, V E

    1985-12-01

    Trichloropropanes have been identified as environmental contaminants in sediments of the Great Lakes region of North America. Since these chemicals had the potential to find their way into drinking water, a 90-day feeding study was carried out in order to determine their subchronic toxicity. Groups of 10 male and 10 female weanling Sprague-Dawley rats were supplied drinking water ad libitum, containing 1,2,3- or 1,1,2-trichloropropane at concentrations of 1, 10, 100 or 1000 mg/L for 13 weeks. Emulphor (0.5%) was used to solubilize the chemicals. At the end of the study, the animals were killed and examined for gross and microscopic changes. Heart, liver, brain, kidney and spleen were excised and weighed. Blood was collected and subjected to a comprehensive hematological analysis. Serum was collected and profiled for changes in 12 biochemical parameters and a portion of liver was used to determined mixed function oxidase activity. Although three animals died during the study, their deaths could not be related to treatment. Decreased growth rate was observed in both sexes of the group receiving 1000 mg/L 1,2,3-trichloropropane. There was an increase in liver, kidney and brain weights (relative to body weight) in rats of both sexes fed 1000 mg/L 1,2,3-trichloropropane. Fatty livers were observed in some of the treated animals but a clear dose-relationship was not evident. An elevation in serum cholesterol was observed in female rats fed the highest dose of 1,2,3-trichloropropane.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Muscle atrophy and bone loss after 90 days' bed rest and the effects of flywheel resistive exercise and pamidronate: results from the LTBR study.

    PubMed

    Rittweger, Jörn; Frost, Harold M; Schiessl, Hans; Ohshima, Hiroshi; Alkner, Björn; Tesch, Per; Felsenberg, Dieter

    2005-06-01

    Muscle atrophy and bone loss pose substantial problems for long-term space flight and in clinical immobilization. We therefore tested the efficacy of flywheel resistive exercise and pamidronate to counteract such losses. Twenty five young healthy males underwent strict bed rest with -6 degrees head-down tilt for 90 days. Subjects were randomized into an exercise group that practiced resistive exercise with a 'flywheel' (FW) device every 2-3 days, a pamidronate group (Pam) that received 60 mg pamidronate i.v. 14 days prior to bed rest and a control group (Ctrl) that received none of these countermeasures. During the study, Ca(++) and protein intake were controlled. Peripheral quantitative computed tomography (pQCT) was used to assess bone mineral content (BMC) and muscle cross sectional area (mCSA) of calf and forearm. Measurements were taken twice during baseline data collection, after 28 and after 89 days bed rest, and after 14 days recovery. On the same days, urinary Pyridinoline excretion and serum levels of alkaline phosphatase, Ca(++) and PTH were measured. Pre-study exercise habits were assessed through the Freiburg questionnaire. Losses in calf mCSA were significantly reduced in FW (Ctrl: -25.6% +/- 2.5% Pam: -25.6% +/- 3.7%, FW: -17.3% +/- 2.7%), but not in the forearm mCSA (Ctrl: -6.4% +/- 4.33%, Pam: -7.7% +/- 4.1%, FW: -7.6% +/- 3.3%). Both diaphyseal and epiphyseal BMC losses of the tibia were mitigated in Pam and FW as compared to Ctrl, although this was significant only at the diaphysis. Inter-individual variability was significantly greater for changes in BMC than in mCSA, and correlation of BMC losses was poor among different locations of the tibia. A significant positive correlation was found between change in tibia epiphyseal BMC and serum cortisol levels. These findings suggest that both countermeasures are only partly effective to preserve BMC (FW and Pam) and mCSA (FW) of the lower leg during bed rest. The partial efficacy of flywheel exercise

  12. A 90-day repeated dose oral (gavage) toxicity study of perfluorohexanoic acid (PFHxA) in rats (with functional observational battery and motor activity determinations).

    PubMed

    Chengelis, Christopher P; Kirkpatrick, Jeannie B; Radovsky, Ann; Shinohara, Motoki

    2009-06-01

    Possible toxic effects of perfluorohexanoic acid (PFHxA) were evaluated when administered orally by gavage to rats at levels up to 200mg/kg/day for 90 days. Lower body weight gains were noted in the 10, 50 and 200mg/kg/day group males (not dose-responsive) throughout dosing. Other changes included lower red blood cell parameters, higher reticulocyte counts and lower globulin in the 200mg/kg/day group males and females, higher liver enzymes in males at 50 and 200mg/kg/day, lower total protein and higher albumin/globulin ratio, and lower cholesterol, calcium in males at 200mg/kg/day. Minimal centrilobular hepatocellular hypertrophy was present in 200mg/kg/day group males and correlated with higher liver weights and slightly higher peroxisome beta oxidation activity at the end of the dosing period. Based on liver histopathology and liver weight changes, the no-observed-adverse-effect level (NOAEL) for oral administration was 50mg/kg/day for males and 200mg/kg/day for females.

  13. Toxicological Study No. 75-51-YJ81-93, 4-Amino-2-Nitrotoluene (4A2NT) Oral Approximate Lethal Dose 14-day Range Finding 90-Day Subchronic Feeding Studies in Rats, August 1991-November 1993

    DTIC Science & Technology

    1994-07-01

    NOVEMBER 1993 1. PURPOSE. The oral approximate lethal dose study was conducted todetennine an approximate dosage range at which to begin the 14-day...5000 mg/Kg. The 14-day range fmding study suggested a probable compound related effect in the薘~m (high dose ) exposure groups of both sexes and a...possible compound related effect mIlle 1000 ppm (middle dose ) exposure groups of both sexes. An NOAEL was not established for the 90-day subchronic

  14. Report of an Expert Panel on the reanalysis by of a 90-day study conducted by Monsanto in support of the safety of a genetically modified corn variety (MON 863).

    PubMed

    Doull, J; Gaylor, D; Greim, H A; Lovell, D P; Lynch, B; Munro, I C

    2007-11-01

    MON 863, a genetically engineered corn variety that contains the gene for modified Bacillus thuringiensis Cry3Bb1 protein to protect against corn rootworm, was tested in a 90-day toxicity study as part of the process to gain regulatory approval. This study was reanalyzed by Séralini et al. who contended that the study showed possible hepatorenal effects of MON 863. An Expert Panel was convened to assess the original study results as analyzed by the Monsanto Company and the reanalysis conducted by Séralini et al. The Expert Panel concludes that the Séralini et al. reanalysis provided no evidence to indicate that MON 863 was associated with adverse effects in the 90-day rat study. In each case, statistical findings reported by both Monsanto and Séralini et al. were considered to be unrelated to treatment or of no biological or clinical importance because they failed to demonstrate a dose-response relationship, reproducibility over time, association with other relevant changes (e.g., histopathology), occurrence in both sexes, difference outside the normal range of variation, or biological plausibility with respect to cause-and-effect. The Séralini et al. reanalysis does not advance any new scientific data to indicate that MON 863 caused adverse effects in the 90-day rat study.

  15. Exposure to Pb, Cd, and As mixtures potentiates the production of oxidative stress precursors: 30-day, 90-day, and 180-day drinking water studies in rats

    SciTech Connect

    Whittaker, Margaret H.; Wang, Gensheng; Chen Xueqing; Lipsky, Michael; Smith, Donald; Gwiazda, Roberto; Fowler, Bruce A.

    2011-07-15

    Exposure to chemical mixtures is a common and important determinant of toxicity and is of particular concern due to their appearance in sources of drinking water. Despite this, few in vivo mixture studies have been conducted to date to understand the health impact of chemical mixtures compared to single chemicals. Interactive effects of lead (Pb), cadmium (Cd) and arsenic (As) were evaluated in 30-, 90-, and 180-day factorial design drinking water studies in rats designed to test the hypothesis that ingestion of such mixtures at individual component Lowest-Observed-Effect-Levels (LOELs) results in increased levels of the pro-oxidant delta aminolevulinic acid (ALA), iron, and copper. LOEL levels of Pb, Cd, and As mixtures resulted in the increased presence of mediators of oxidative stress such as ALA, copper, and iron. ALA increases were followed by statistically significant increases in kidney copper in the 90- and 180-day studies. Statistical evidence of interaction was identified for six biologically relevant variables: blood delta aminolevulinic acid dehydratase (ALAD), kidney ALAD, urinary ALA, urinary iron, kidney iron, and kidney copper. The current investigations underscore the importance of considering interactive effects that common toxic agents such as Pb, Cd, and As may have upon one another at low-dose levels. The interactions between known toxic trace elements at biologically relevant concentrations shown here demonstrate a clear need to rigorously review methods by which national/international agencies assess health risks of chemicals, since exposures may commonly occur as complex mixtures.

  16. Exposure to Pb, Cd, and As mixtures potentiates the production of oxidative stress precursors: 30-day, 90-day, and 180-day drinking water studies in rats.

    PubMed

    Whittaker, Margaret H; Wang, Gensheng; Chen, Xue-Qing; Lipsky, Michael; Smith, Donald; Gwiazda, Roberto; Fowler, Bruce A

    2011-07-15

    Exposure to chemical mixtures is a common and important determinant of toxicity and is of particular concern due to their appearance in sources of drinking water. Despite this, few in vivo mixture studies have been conducted to date to understand the health impact of chemical mixtures compared to single chemicals. Interactive effects of lead (Pb), cadmium (Cd) and arsenic (As) were evaluated in 30-, 90-, and 180-day factorial design drinking water studies in rats designed to test the hypothesis that ingestion of such mixtures at individual component Lowest-Observed-Effect-Levels (LOELs) results in increased levels of the pro-oxidant delta aminolevulinic acid (ALA), iron, and copper. LOEL levels of Pb, Cd, and As mixtures resulted in the increased presence of mediators of oxidative stress such as ALA, copper, and iron. ALA increases were followed by statistically significant increases in kidney copper in the 90- and 180-day studies. Statistical evidence of interaction was identified for six biologically relevant variables: blood delta aminolevulinic acid dehydratase (ALAD), kidney ALAD, urinary ALA, urinary iron, kidney iron, and kidney copper. The current investigations underscore the importance of considering interactive effects that common toxic agents such as Pb, Cd, and As may have upon one another at low-dose levels. The interactions between known toxic trace elements at biologically relevant concentrations shown here demonstrate a clear need to rigorously review methods by which national/international agencies assess health risks of chemicals, since exposures may commonly occur as complex mixtures.

  17. Safety evaluation of AB-LIFE(®) (Lactobacillus plantarum CECT 7527, 7528 and 7529): Antibiotic resistance and 90-day repeated-dose study in rats.

    PubMed

    Mukerji, Pushkor; Roper, Jason M; Stahl, Buffy; Smith, Amy B; Burns, Frank; Rae, Jessica Caverly; Yeung, Nicolas; Lyra, Anna; Svärd, Laura; Saarinen, Markku T; Alhoniemi, Esa; Ibarra, Alvin; Ouwehand, Arthur C

    2016-06-01

    AB-LIFE(®) is a probiotic product consisting of equal parts of three strains of Lactobacillus plantarum (CECT 7527, 7528, and 7529) blended with inert excipients. Whole genome sequencing was performed on each of the three strains. Antibiotic resistance was evaluated by genomic mining for resistance genes, and assessment for transferability. No risk of transfer potential was identified for any antibiotic resistance genes in the three strains. AB-LIFE(®) was evaluated for potential subchronic oral toxicity in rats, with dosages of 300 and 1000 mg/kg BW/day (equivalent to 5.55 × 10(10) and 1.85 × 10(11) CFU/kg BW/day). Survival of the three test strains through the gastrointestinal tract was supported by fecal analysis. No adverse effects were identified with respect to in-life parameters, clinical or anatomic pathology, translocation, or fecal chemical analyses. The no-observed-adverse-effect level (NOAEL) for AB-LIFE(®) in male and female rats was 1000 mg/kg BW/day (1.85 × 10(11) CFU of AB-LIFE(®)/kg BW/day), the highest dose level evaluated. These results, in conjunction with a previous acute toxicity study in rats, support the conclusion that AB-LIFE(®) is safe for human consumption.

  18. A 90-day subchronic study of rats fed lean pork from genetically modified pigs with muscle-specific expression of recombinant follistatin.

    PubMed

    Zou, Shiying; Tang, Min; He, Xiaoyun; Cao, Yuan; Zhao, Jie; Xu, Wentao; Liang, Zhihong; Huang, Kunlun

    2015-11-01

    Because cardiovascular disease incidence has rapidly increased in recent years, people are choosing relatively healthier diets with low animal fat. A transgenic pig with low fat and a high percentage of lean meat was created in 2011; this pig overexpresses the follistatin (FST) gene. To evaluate the safety of lean pork derived from genetically modified (GM) pigs, a subchronic oral toxicity study was conducted using Sprague-Dawley rats. GM pork and non-GM pork were incorporated into the diet at levels of 3.75%, 7.5%, and 15% (w/w), and the main nutrients of the various diets were subsequently balanced. The safety of GM pork was assessed by comparison of the toxicology response variables in Sprague-Dawley rats consuming diets containing GM pork with those consuming non-GM pork. No treatment-related adverse or toxic effects were observed based on an examination of the daily clinical signs, body weight, food consumption, hematology, serum biochemistry, and organ weight or based on gross and histopathological examination. The results demonstrate that GM pork is as safe for consumption as conventional pork.

  19. Evaluation of the Tobacco Heating System 2.2. Part 6: 90-day OECD 413 rat inhalation study with systems toxicology endpoints demonstrates reduced exposure effects of a mentholated version compared with mentholated and non-mentholated cigarette smoke.

    PubMed

    Oviedo, Alberto; Lebrun, Stefan; Kogel, Ulrike; Ho, Jenny; Tan, Wei Teck; Titz, Bjoern; Leroy, Patrice; Vuillaume, Gregory; Bera, Monali; Martin, Florian; Rodrigo, Gregory; Esposito, Marco; Dempsey, Ruth; Ivanov, Nikolai V; Hoeng, Julia; Peitsch, Manuel C; Vanscheeuwijck, Patrick

    2016-11-30

    The toxicity of a mentholated version of the Tobacco Heating System (THS2.2M), a candidate modified risk tobacco product (MRTP), was characterized in a 90-day OECD inhalation study. Differential gene and protein expression analysis of nasal epithelium and lung tissue was also performed to record exposure effects at the molecular level. Rats were exposed to filtered air (sham), to THS2.2M (at 15, 23 and 50 μg nicotine/l), to two mentholated reference cigarettes (MRC) (at 23 μg nicotine/l), or to the 3R4F reference cigarette (at 23 μg nicotine/l). MRCs were designed to meet 3R4F specifications. Test atmosphere analyses demonstrated that aldehydes were reduced by 75%-90% and carbon monoxide by 98% in THS2.2M aerosol compared with MRC smoke; aerosol uptake was confirmed by carboxyhemoglobin and menthol concentrations in blood, and by the quantities of urinary nicotine metabolites. Systemic toxicity and alterations in the respiratory tract were significantly lower in THS2.2M-exposed rats compared with MRC and 3R4F. Pulmonary inflammation and the magnitude of the changes in gene and protein expression were also dramatically lower after THS2.2M exposure compared with MRCs and 3R4F. No menthol-related effects were observed after MRC mainstream smoke-exposure compared with 3R4F.

  20. Evaluation of the Tobacco Heating System 2.2. Part 4: 90-day OECD 413 rat inhalation study with systems toxicology endpoints demonstrates reduced exposure effects compared with cigarette smoke.

    PubMed

    Wong, Ee Tsin; Kogel, Ulrike; Veljkovic, Emilija; Martin, Florian; Xiang, Yang; Boue, Stephanie; Vuillaume, Gregory; Leroy, Patrice; Guedj, Emmanuel; Rodrigo, Gregory; Ivanov, Nikolai V; Hoeng, Julia; Peitsch, Manuel C; Vanscheeuwijck, Patrick

    2016-11-30

    The objective of the study was to characterize the toxicity from sub-chronic inhalation of test atmospheres from the candidate modified risk tobacco product (MRTP), Tobacco Heating System version 2.2 (THS2.2), and to compare it with that of the 3R4F reference cigarette. A 90-day nose-only inhalation study on Sprague-Dawley rats was performed, combining classical and systems toxicology approaches. Reduction in respiratory minute volume, degree of lung inflammation, and histopathological findings in the respiratory tract organs were significantly less pronounced in THS2.2-exposed groups compared with 3R4F-exposed groups. Transcriptomics data obtained from nasal epithelium and lung parenchyma showed concentration-dependent differential gene expression following 3R4F exposure that was less pronounced in the THS2.2-exposed groups. Molecular network analysis showed that inflammatory processes were the most affected by 3R4F, while the extent of THS2.2 impact was much lower. Most other toxicological endpoints evaluated did not show exposure-related effects. Where findings were observed, the effects were similar in 3R4F- and THS2.2-exposed animals. In summary, toxicological changes observed in the respiratory tract organs of THS2.2 aerosol-exposed rats were much less pronounced than in 3R4F-exposed rats while other toxicological endpoints either showed no exposure-related effects or were comparable to what was observed in the 3R4F-exposed rats.

  1. Baroreflex Sensitivity Decreases During 90-Day Bed Rest

    NASA Technical Reports Server (NTRS)

    Stenger, M. B.; Arzeno, N. M.; Platts, S. H.

    2008-01-01

    Baroreflex sensitivity (BRS) decreases during spaceflight and simulated spaceflight (head down bed rest [BR]). However, previous studies have only examined BRS in response to a limited blood pressure (BP) range or to a single sudden change in BP. PURPOSE: The purpose of this study was to examine BRS during 90 days of 6deg head-down tilt BR over a broad range of BP perturbations. METHODS: Nineteen normal volunteers (12M, 7F) were tested one day before BR, and then near BR days 30, 60 and 90. BP was pharmacologically altered by continuous infusions of phenylephrine (PE) and sodium nitroprusside (SNP). Electrocardiogram and continuous BP were collected during 10 min of normal saline (NS), followed by increasing concentrations of PE (10 min each of 0.4, 0.8 and 1.6 micro-g/kg/min). After a 20 min break, NS was infused again for 10 min, followed by increasing concentrations of SNP (10 min each of 0.4, 0.8, 1.2 micro-g/kg/min). Baroreceptor sensitivity was measured as the slope of a sequence of 3 or more beats in which the systolic BP and following R-R interval (RR) both increased or decreased. Spectral heart rate variability (HRV) and mean RR were analyzed using data from only the NS infusions. Two-way repeated-measures analysis of variance was performed to examine the effects of BR and gender. RESULTS: RR decreased (p<0.001) from pre- BR across BR days. High frequency in normalized units, a measure of parasympathetic activity, decreased with BR (p=0.027) and was lower (p=0.046) in men (0.39+/-0.02, mean+/-SEM) than women (0.48+/-0.02). The spontaneous baroreflex slope, our measure of BRS, increased with PE and decreased with SNP across BR (p<0.001). The percentage decrease in BRS from pre- to post-BR appeared to be larger in women (43.6+/-7.0%) than in men (31.3+/-3.9%, p=0.06). CONCLUSION: Parasympathetic activity and baroreflex sensitivity decrease during 90 days of BR, and BRS tends to diminish more in women than in men.

  2. Prognostic Abilities and Quality Assessment of Models for the Prediction of 90-Day Mortality in Liver Transplant Waiting List Patients

    PubMed Central

    Barthold, Marc; Kaltenborn, Alexander

    2017-01-01

    Background Model of end-stage liver disease (MELD)-score and diverse variants are widely used for prognosis on liver transplant waiting-lists. Methods 818 consecutive patients on the liver transplant waiting-list included to calculate the MELD, MESO Index, MELD-Na, UKELD, iMELD, refitMELD, refitMELD-Na, upMELD and PELD-scores. Prognostic abilities for 90-day mortality were investigated applying Receiver-operating-characteristic-curve analysis. Independent risk factors for 90-day mortality were identified with multivariable binary logistic regression modelling. Methodological quality of the underlying development studies was assessed with a systematic assessment tool. Results 74 patients (9%) died on the liver transplant waiting list within 90 days after listing. All but one scores, refitMELD-Na, had acceptable prognostic performance with areas under the ROC-curves (AUROCs)>0.700. The iMELD performed best (AUROC = 0.798). In pediatric cases, the PELD-score just failed to reach the acceptable threshold with an AUROC = 0.699. All scores reached a mean quality score of 72.3%. Highest quality scores could be achieved by the UKELD and PELD-scores. Studies specifically lack statistical validity and model evaluation. Conclusions Inferior quality assessment of prognostic models does not necessarily imply inferior prognostic abilities. The iMELD might be a more reliable tool representing urgency of transplantation than the MELD-score. PELD-score is assumedly not accurate enough to allow graft allocation decision in pediatric liver transplantation. PMID:28129338

  3. First Report of 90-Day Support of Two Calves with a Continuous-Flow Total Artificial Heart

    PubMed Central

    Karimov, Jamshid H.; Moazami, Nader; Kobayashi, Mariko; Sale, Shiva; Such, Kimberly; Byram, Nicole; Sunagawa, Gengo; Horvath, David; Gao, Shengqiang; Kuban, Barry; Golding, Leonard A.; Fukamachi, Kiyotaka

    2015-01-01

    Objective The Cleveland Clinic continuous-flow total artificial heart (CFTAH) is a compact, single-piece, valveless, pulsatile pump providing self-regulated hemodynamic output to left/right circulation. We evaluated chronic in vivo pump performance, physiologic and hemodynamic parameters, and biocompatibility of the CFTAH in a well-established calf model. Methods CFTAH pumps have been implanted in 17 calves total. Hemodynamics, pump performance, and device-related adverse events were evaluated during studies and at necropsy. Results In vivo experiments demonstrated good hemodynamic performance (pump flow, 7.3 ± 0.7 L/min; left atrial pressure [LAP], 16 ± 3 mm Hg; right atrial pressure [RAP], 17 ± 3 mm Hg; RAP-LAP difference, 1 ± 2 mm Hg; mean arterial pressure, 103 ± 7 mm Hg; arterial pulse pressure, 30 ± 11 mm Hg; pulmonary arterial pressure, 34 ± 5 mm Hg). The CFTAH has operated within design specifications and never failed. With ever-improving pump design, the implants have shown no chronic hemolysis. Three recent animals with the CFTAH recovered well, with no postoperative anticoagulation, during planned in vivo durations of 30, 90, and 90 days (last two were intended to be 90-day studies). All these longest-surviving cases showed good biocompatibility, with no thromboembolism in organs. Conclusions The current CFTAH has demonstrated reliable self-regulation of hemodynamic output and acceptable biocompatibility without anticoagulation throughout 90 days of chronic implantation in calves. Meeting these milestones is in accord with our strategy to achieve transfer of this unique technology to surgical practice, thus filling the urgent need for cardiac replacement devices as destination therapy. PMID:26173607

  4. A 90-Day Tenofovir Reservoir Intravaginal Ring for Mucosal HIV Prophylaxis

    PubMed Central

    Johnson, Todd J.; Clark, Meredith R.; Albright, Theodore H.; Nebeker, Joel S.; Tuitupou, Anthony L.; Clark, Justin T.; Fabian, Judit; McCabe, R. Tyler; Chandra, Neelima; Doncel, Gustavo F.; Friend, David R.

    2012-01-01

    A vaginal gel containing the antiretroviral tenofovir (TFV) recently demonstrated 39% protection against HIV infection in women. We designed and evaluated a novel reservoir TFV intravaginal ring (IVR) to potentially improve product effectiveness by providing a more controlled and sustained vaginal dose to maintain cervicovaginal concentrations. Polyurethane tubing of various hydrophilicities was filled with a high-density TFV/glycerol/water semisolid paste and then end-sealed to create IVRs. In vitro, TFV release increased with polyurethane hydrophilicity, with 35 weight percent water-swelling polyurethane IVRs achieving an approximately 10-mg/day release for 90 days with mechanical stiffness similar to that of the commercially available NuvaRing. This design was evaluated in two 90-day in vivo sheep studies for TFV pharmacokinetics and safety. Overall, TFV vaginal tissue, vaginal fluid, and plasma levels were relatively time independent over the 90-day duration at approximately 104 ng/g, 106 ng/g, and 101 ng/ml, respectively, near or exceeding the highest observed concentrations in a TFV 1% gel control group. TFV vaginal fluid concentrations were approximately 1,000-fold greater than levels shown to provide significant protection in women using the TFV 1% gel. There were no toxicological findings following placebo and TFV IVR treatment for 28 or 90 days, although slight to moderate increases in inflammatory infiltrates in the vaginal epithelia were observed in these animals compared to naïve animals. In summary, the controlled release of TFV from this reservoir IVR provided elevated sheep vaginal concentrations for 90 days to merit its further evaluation as an HIV prophylactic. PMID:23006751

  5. 49 CFR 24.402 - Replacement housing payment for 90-day occupants.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Replacement housing payment for 90-day occupants... Payments § 24.402 Replacement housing payment for 90-day occupants. (a) Eligibility. A tenant or owner... occupied the displacement dwelling for at least 90 days immediately prior to the initiation of...

  6. 49 CFR 24.402 - Replacement housing payment for 90-day occupants.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Replacement housing payment for 90-day occupants... Payments § 24.402 Replacement housing payment for 90-day occupants. (a) Eligibility. A tenant or owner... occupied the displacement dwelling for at least 90 days immediately prior to the initiation of...

  7. 49 CFR 24.402 - Replacement housing payment for 90-day occupants.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Replacement housing payment for 90-day occupants... Payments § 24.402 Replacement housing payment for 90-day occupants. (a) Eligibility. A tenant or owner... occupied the displacement dwelling for at least 90 days immediately prior to the initiation of...

  8. 29 CFR 2590.715-2708 - Prohibition on waiting periods that exceed 90 days.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 9 2014-07-01 2014-07-01 false Prohibition on waiting periods that exceed 90 days. 2590... PLANS Other Requirements § 2590.715-2708 Prohibition on waiting periods that exceed 90 days. (a) General... not apply any waiting period that exceeds 90 days, in accordance with the rules of this section....

  9. 49 CFR 24.503 - Replacement housing payment for 90-day mobile home occupants.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Replacement housing payment for 90-day mobile home... Replacement housing payment for 90-day mobile home occupants. A displaced tenant or owner-occupant of a mobile... 90 days immediately prior to the initiation of negotiations; (b) The person meets the other...

  10. 49 CFR 24.402 - Replacement housing payment for 90-day occupants.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Replacement housing payment for 90-day occupants... Payments § 24.402 Replacement housing payment for 90-day occupants. (a) Eligibility. A tenant or owner... occupied the displacement dwelling for at least 90 days immediately prior to the initiation of...

  11. 49 CFR 24.503 - Replacement housing payment for 90-day mobile home occupants.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Replacement housing payment for 90-day mobile home... Replacement housing payment for 90-day mobile home occupants. A displaced tenant or owner-occupant of a mobile... 90 days immediately prior to the initiation of negotiations; (b) The person meets the other...

  12. 49 CFR 24.402 - Replacement housing payment for 90-day occupants.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Replacement housing payment for 90-day occupants... Payments § 24.402 Replacement housing payment for 90-day occupants. (a) Eligibility. A tenant or owner... occupied the displacement dwelling for at least 90 days immediately prior to the initiation of...

  13. 49 CFR 24.503 - Replacement housing payment for 90-day mobile home occupants.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Replacement housing payment for 90-day mobile home... Replacement housing payment for 90-day mobile home occupants. A displaced tenant or owner-occupant of a mobile... 90 days immediately prior to the initiation of negotiations; (b) The person meets the other...

  14. The 90-day oral toxicity of d-psicose in male Wistar rats.

    PubMed

    Matsuo, Tatsuhiro; Ishii, Reika; Shirai, Yoko

    2012-03-01

    d-Psicose is a rare sugar present in small quantities in natural products. In a previous study, we showed that d-psicose suppresses increase in plasma glucose and reduces body fat accumulation in rats. Based on acute toxicity testing in rats, d-psicose is classified as an ordinary substance (LD(50) = 16 g/kg). Elucidating the effects of sub-chronic feeding of d-psicose in rats is essential before it can be utilized as a physiologically functional food. In this study, male Wistar rats (3 weeks old) were fed diets containing 3% d-psicose or sucrose for 90 days. The body weight gain and intra-abdominal adipose tissue weight did not differ between the sucrose and the d-psicose groups. The weights of the liver and kidneys were significantly higher in the d-psicose group than in the sucrose group. However, no gross pathological findings were evident at dietary doses of 3% d-psicose or were correlated with hypertrophy of the liver and kidney. In a clinical chemistry analysis, the erythrocyte and leukocyte courts were significantly higher in the d-psicose group, but that was not considered to be toxicologically significant. Therefore, the present study found no adverse effects of d-psicose in rats fed a diet containing 3% d-psicosefor 90 days.

  15. General Aviation Aircraft Reliability Study

    NASA Technical Reports Server (NTRS)

    Pettit, Duane; Turnbull, Andrew; Roelant, Henk A. (Technical Monitor)

    2001-01-01

    This reliability study was performed in order to provide the aviation community with an estimate of Complex General Aviation (GA) Aircraft System reliability. To successfully improve the safety and reliability for the next generation of GA aircraft, a study of current GA aircraft attributes was prudent. This was accomplished by benchmarking the reliability of operational Complex GA Aircraft Systems. Specifically, Complex GA Aircraft System reliability was estimated using data obtained from the logbooks of a random sample of the Complex GA Aircraft population.

  16. 25 CFR 900.17 - Can the statutory 90-day period be extended?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 2 2012-04-01 2012-04-01 false Can the statutory 90-day period be extended? 900.17... ASSISTANCE ACT Review and Approval of Contract Proposals § 900.17 Can the statutory 90-day period be extended...-day deadline applies....

  17. 25 CFR 900.17 - Can the statutory 90-day period be extended?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Can the statutory 90-day period be extended? 900.17... ASSISTANCE ACT Review and Approval of Contract Proposals § 900.17 Can the statutory 90-day period be extended...-day deadline applies....

  18. 25 CFR 900.17 - Can the statutory 90-day period be extended?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 2 2014-04-01 2014-04-01 false Can the statutory 90-day period be extended? 900.17... ASSISTANCE ACT Review and Approval of Contract Proposals § 900.17 Can the statutory 90-day period be extended...-day deadline applies....

  19. 25 CFR 900.17 - Can the statutory 90-day period be extended?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 2 2013-04-01 2013-04-01 false Can the statutory 90-day period be extended? 900.17... ASSISTANCE ACT Review and Approval of Contract Proposals § 900.17 Can the statutory 90-day period be extended...-day deadline applies....

  20. 49 CFR 24.503 - Replacement housing payment for 90-day mobile home occupants.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Replacement housing payment for 90-day mobile home... ASSISTANCE AND REAL PROPERTY ACQUISITION FOR FEDERAL AND FEDERALLY-ASSISTED PROGRAMS Mobile Homes § 24.503 Replacement housing payment for 90-day mobile home occupants. A displaced tenant or owner-occupant of a...

  1. Evaluation of the Tobacco Heating System 2.2 (THS2.2). Part 5: microRNA expression from a 90-day rat inhalation study indicates that exposure to THS2.2 aerosol causes reduced effects on lung tissue compared with cigarette smoke.

    PubMed

    Sewer, Alain; Kogel, Ulrike; Talikka, Marja; Wong, Ee Tsin; Martin, Florian; Xiang, Yang; Guedj, Emmanuel; Ivanov, Nikolai V; Hoeng, Julia; Peitsch, Manuel C

    2016-11-30

    Modified-risk tobacco products (MRTP) are designed to reduce the individual risk of tobacco-related disease as well as population harm compared to smoking cigarettes. Experimental proof of their benefit needs to be provided at multiple levels in research fields. Here, we examined microRNA (miRNA) levels in the lungs of rats exposed to a candidate modified-risk tobacco product, the Tobacco Heating System 2.2 (THS2.2) in a 90-day OECD TG-413 inhalation study. Our aim was to assess the miRNA response to THS2.2 aerosol compared with the response to combustible cigarettes (CC) smoke from the reference cigarette 3R4F. CC smoke exposure, but not THS2.2 aerosol exposure, caused global miRNA downregulation, which may be explained by the interference of CC smoke constituents with the miRNA processing machinery. Upregulation of specific miRNA species, such as miR-146a/b and miR-182, indicated that they are causal elements in the inflammatory response in CC-exposed lungs, but they were reduced after THS2.2 aerosol exposure. Transforming transcriptomic data into protein activity based on corresponding downstream gene expression, we identified potential mechanisms for miR-146a/b and miR-182 that were activated by CC smoke but not by THS2.2 aerosol and possibly involved in the regulation of those miRNAs. The inclusion of miRNA profiling in systems toxicology approaches increases the mechanistic understanding of the complex exposure responses.

  2. Parametric Mass Reliability Study

    NASA Technical Reports Server (NTRS)

    Holt, James P.

    2014-01-01

    The International Space Station (ISS) systems are designed based upon having redundant systems with replaceable orbital replacement units (ORUs). These ORUs are designed to be swapped out fairly quickly, but some are very large, and some are made up of many components. When an ORU fails, it is replaced on orbit with a spare; the failed unit is sometimes returned to Earth to be serviced and re-launched. Such a system is not feasible for a 500+ day long-duration mission beyond low Earth orbit. The components that make up these ORUs have mixed reliabilities. Components that make up the most mass-such as computer housings, pump casings, and the silicon board of PCBs-typically are the most reliable. Meanwhile components that tend to fail the earliest-such as seals or gaskets-typically have a small mass. To better understand the problem, my project is to create a parametric model that relates both the mass of ORUs to reliability, as well as the mass of ORU subcomponents to reliability.

  3. Software reliability studies

    NASA Technical Reports Server (NTRS)

    Hoppa, Mary Ann; Wilson, Larry W.

    1994-01-01

    There are many software reliability models which try to predict future performance of software based on data generated by the debugging process. Our research has shown that by improving the quality of the data one can greatly improve the predictions. We are working on methodologies which control some of the randomness inherent in the standard data generation processes in order to improve the accuracy of predictions. Our contribution is twofold in that we describe an experimental methodology using a data structure called the debugging graph and apply this methodology to assess the robustness of existing models. The debugging graph is used to analyze the effects of various fault recovery orders on the predictive accuracy of several well-known software reliability algorithms. We found that, along a particular debugging path in the graph, the predictive performance of different models can vary greatly. Similarly, just because a model 'fits' a given path's data well does not guarantee that the model would perform well on a different path. Further we observed bug interactions and noted their potential effects on the predictive process. We saw that not only do different faults fail at different rates, but that those rates can be affected by the particular debugging stage at which the rates are evaluated. Based on our experiment, we conjecture that the accuracy of a reliability prediction is affected by the fault recovery order as well as by fault interaction.

  4. 19 CFR Annex Viii-A to Part 351 - Schedule for 90-Day Sunset Reviews

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 3 2014-04-01 2014-04-01 false Schedule for 90-Day Sunset Reviews VIII Annex VIII... AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-A Annex VIII-A to Part 351—Schedule for 90-Day Sunset Reviews Day 1 Event Regulation 0 Initiation § 351.218(c) 15 Filing of Notice of Intent to Participate...

  5. 19 CFR Annex Viii-A to Part 351 - Schedule for 90-Day Sunset Reviews

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 3 2012-04-01 2012-04-01 false Schedule for 90-Day Sunset Reviews VIII Annex VIII... AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-A Annex VIII-A to Part 351—Schedule for 90-Day Sunset Reviews Day 1 Event Regulation 0 Initiation § 351.218(c) 15 Filing of Notice of Intent to Participate...

  6. 19 CFR Annex Viii-A to Part 351 - Schedule for 90-Day Sunset Reviews

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 3 2013-04-01 2013-04-01 false Schedule for 90-Day Sunset Reviews VIII Annex VIII... AND COUNTERVAILING DUTIES Pt. 351, Annex VIII-A Annex VIII-A to Part 351—Schedule for 90-Day Sunset Reviews Day 1 Event Regulation 0 Initiation § 351.218(c) 15 Filing of Notice of Intent to Participate...

  7. Ferrite logic reliability study

    NASA Technical Reports Server (NTRS)

    Baer, J. A.; Clark, C. B.

    1973-01-01

    Development and use of digital circuits called all-magnetic logic are reported. In these circuits the magnetic elements and their windings comprise the active circuit devices in the logic portion of a system. The ferrite logic device belongs to the all-magnetic class of logic circuits. The FLO device is novel in that it makes use of a dual or bimaterial ferrite composition in one physical ceramic body. This bimaterial feature, coupled with its potential for relatively high speed operation, makes it attractive for high reliability applications. (Maximum speed of operation approximately 50 kHz.)

  8. 90-day postoperative mortality is a legitimate measure of hepatopancreatobiliary surgical quality

    PubMed Central

    Mise, Yoshihiro; Vauthey, Jean-Nicolas; Zimmitti, Giuseppe; Parker, Nathan H.; Conrad, Claudius; Aloia, Thomas A.; Lee, Jeffery E.; Fleming, Jason B.; Katz, Matthew H. G.

    2015-01-01

    Objective To investigate the legitimacy of 90-day mortality as a measure of hepatopancreatobiliary quality. Summary Background Data The 90-day mortality rate has been increasingly but not universally reported after hepatopancreatobiliary surgery. The legitimacy of this definition as a measure of surgical quality has not been evaluated. Methods We retrospectively reviewed the causes of all deaths that occurred within 365 postoperative days in patients undergoing hepatectomy (n = 2811) and/or pancreatectomy (n = 1092) from January 1997 through December 2012. The rates of surgery-related, disease-related, and overall mortality within 30 days, within 30 days or during the index hospitalization, within 90 days, and within 180 days following surgery were calculated. Results Seventy-nine (3%) surgery-related deaths and 92 (3%) disease-related deaths occurred within 365 days after hepatectomy. Twenty (2%) surgery-related deaths and 112 (10%) disease-related deaths occurred within 365 days after pancreatectomy. The overall mortality rates at 99 day and 118 days optimally reflected surgery-related mortality following hepatobiliary and pancreatic operations, respectively. The 90-day overall mortality rate was a less sensitive but equivalently specific measure of surgery-related death. Conclusions and Relevance The 99-day and 118-day definitions of postoperative mortality optimally reflected surgery-related mortality following hepatobiliary and pancreatic operations, respectively. However, among commonly reported metrics, the 90-day overall mortality rate represents a legitimate measure of surgical quality. PMID:25590497

  9. Evaluation of silica nanoparticle toxicity after topical exposure for 90 days

    PubMed Central

    Ryu, Hwa Jung; Seong, Nak-won; So, Byoung Joon; Seo, Heung-sik; Kim, Jun-ho; Hong, Jeong-Sup; Park, Myeong-kyu; Kim, Min-Seok; Kim, Yu-Ri; Cho, Kyu-Bong; Seo, Mu Yeb; Kim, Meyoung-Kon; Maeng, Eun Ho; Son, Sang Wook

    2014-01-01

    Silica is a very common material that can be found in both crystalline and amorphous forms. Well-known toxicities of the lung can occur after exposure to the crystalline form of silica. However, the toxicities of the amorphous form of silica have not been thoroughly studied. The majority of in vivo studies of amorphous silica nanoparticles (NPs) were performed using an inhalation exposure method. Since silica NPs can be commonly administered through the skin, a study of dermal silica toxicity was necessary to determine any harmful effects from dermal exposures. The present study focused on the results of systemic toxicity after applying 20 nm colloidal silica NPs on rat skin for 90 days, in accordance with the Organization for Economic Cooperation and Development test guideline 411 with a good laboratory practice system. Unlike the inhalation route or gastrointestinal route, the contact of silica NPs through skin did not result in any toxicity or any change in internal organs up to a dose of 2,000 mg/kg in rats. PMID:25565831

  10. A 90-Day Oral Toxicological Evaluation of the Methylurate Purine Alkaloid Theacrine

    PubMed Central

    Hirka, Gábor; Glávits, Róbert; Palmer, Philip A.; Endres, John R.; Pasics Szakonyiné, Ilona

    2016-01-01

    A 90-day repeated-dose oral toxicological evaluation was conducted according to GLP and OECD guidelines on the methylurate purine alkaloid theacrine, which is found naturally in certain plants. Four groups of Hsd.Brl.Han Wistar rats (ten/sex/group) were administered theacrine by gavage doses of 0 (vehicle only), 180, 300, and 375 mg/kg bw/day. Two females and one male in the 300 and 375 mg/kg bw/day groups, respectively, died during the study. Histological examination revealed centrilobular hepatocellular necrosis as the probable cause of death. In 375 mg/kg bw/day males, slight reductions in body weight development, food consumption, and feed efficiency, decreased weight of the testes and epididymides and decreased intensity of spermatogenesis in the testes, lack or decreased amount of mature spermatozoa in the epididymides, and decreased amount of prostatic secretions were detected at the end of the three months. At 300 mg/kg bw/day, slight decreases in the weights of the testes and epididymides, along with decreased intensity of spermatogenesis in the testes, and lack or decreased amount of mature spermatozoa in the epididymides were detected in male animals. The NOAEL was considered to be 180 mg/kg bw/day, as at this dose there were no toxicologically relevant treatment-related findings in male or female animals. PMID:27635133

  11. A 90-Day Oral Toxicological Evaluation of the Methylurate Purine Alkaloid Theacrine.

    PubMed

    Clewell, Amy; Hirka, Gábor; Glávits, Róbert; Palmer, Philip A; Endres, John R; Murbach, Timothy S; Marx, Tennille; Pasics Szakonyiné, Ilona

    2016-01-01

    A 90-day repeated-dose oral toxicological evaluation was conducted according to GLP and OECD guidelines on the methylurate purine alkaloid theacrine, which is found naturally in certain plants. Four groups of Hsd.Brl.Han Wistar rats (ten/sex/group) were administered theacrine by gavage doses of 0 (vehicle only), 180, 300, and 375 mg/kg bw/day. Two females and one male in the 300 and 375 mg/kg bw/day groups, respectively, died during the study. Histological examination revealed centrilobular hepatocellular necrosis as the probable cause of death. In 375 mg/kg bw/day males, slight reductions in body weight development, food consumption, and feed efficiency, decreased weight of the testes and epididymides and decreased intensity of spermatogenesis in the testes, lack or decreased amount of mature spermatozoa in the epididymides, and decreased amount of prostatic secretions were detected at the end of the three months. At 300 mg/kg bw/day, slight decreases in the weights of the testes and epididymides, along with decreased intensity of spermatogenesis in the testes, and lack or decreased amount of mature spermatozoa in the epididymides were detected in male animals. The NOAEL was considered to be 180 mg/kg bw/day, as at this dose there were no toxicologically relevant treatment-related findings in male or female animals.

  12. 40 CFR 799.9310 - TSCA 90-day oral toxicity in rodents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... target organs, body weight changes, effects on mortality and any other general or specific toxic effects... REQUIREMENTS Health Effects Test Guidelines § 799.9310 TSCA 90-day oral toxicity in rodents. (a) Scope. This... no-observed-effects level (NOEL) and toxic effects associated with continuous or repeated exposure...

  13. 40 CFR 799.9310 - TSCA 90-day oral toxicity in rodents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... target organs, body weight changes, effects on mortality and any other general or specific toxic effects... REQUIREMENTS Health Effects Test Guidelines § 799.9310 TSCA 90-day oral toxicity in rodents. (a) Scope. This... no-observed-effects level (NOEL) and toxic effects associated with continuous or repeated exposure...

  14. 26 CFR 54.9815-2708 - Prohibition on waiting periods that exceed 90 days.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... days. 54.9815-2708 Section 54.9815-2708 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... on waiting periods that exceed 90 days. (a) General rule. A group health plan, and a health insurance issuer offering group health insurance coverage, must not apply any waiting period that exceeds 90...

  15. Implications of the 90-day episode definition used for the Comprehensive Care for Joint Replacement model

    PubMed Central

    Ellimoottil, Chad; Ryan, Andrew M.; Hou, Hechuan; Dupree, James M.; Hallstrom, Brian; Miller, David C.

    2017-01-01

    Importance Under the Comprehensive Care for Joint Replacement (CJR) model, hospitals are held accountable for nearly all Medicare payments that occur during the initial hospitalization through 90-days post-discharge (i.e., episode of care). It is unknown whether unrelated expenditures resulting from this “broad” episode definition will impact participating hospital’s average 90-day episode payments. Objective To compare the CJR program’s broad episode definition to a clinically-narrow episode definition Design We identified Medicare claims for patients in Michigan who underwent joint replacement from 2011 through 2013. Using specifications from the CJR model and the clinically-narrow Hospital Compare payment measure, we constructed episodes of care and calculated 90-day episode payments. We then compared hospitals’ average 90-day episode payments using the two episode definitions and fit linear regression models to understand whether payment differences were associated with specific hospital characteristics (average CMS-HCC risk score, rural hospital status, joint replacement volume, percentage of Medicaid discharges, teaching hospital status, number of beds, percentage of joint replacements performed on African American patients and median income of the hospital’s county). Setting All Michigan hospitals located in metropolitan statistical areas Participants Medicare beneficiaries Main Outcome and Measure(s) The correlation and difference between average 90-day episode payments using the broad CJR model episode definition and the clinically-narrow Hospital Compare episode definition. Results We identified 23,251 joint replacement episodes. 90-day episode payments using the broad CJR episode definition ranged from $17,349 to $29,465 (mean: $22,122, standard deviation: $2,600). Episode payments were slightly lower (mean: $21,670) when the Hospital Compare episode definition was used. Both methods were strongly correlated (r=0.99, p<0.001). The average

  16. Effects of 90-day feeding of transgenic Bt rice TT51 on the reproductive system in male rats.

    PubMed

    Wang, Er Hui; Yu, Zhou; Hu, Jing; Xu, Hai Bin

    2013-12-01

    Rice is a staple food crop; however, the threat of pests leads to a serious decline in its output and quality. The CryAb/CryAc gene, encodes a synthetic fusion Bacillus thuringiensis (Bt) crystal protein, was introduced into rice MingHui63 to produce insect-resistant rice TT51. This study was undertaken to investigate potential unintended effects of TT51 on the reproductive system in male rats. Male rats were treated with diets containing 60% of either TT51 or MingHui63 by weight, nutritionally balanced to an AIN93G diet, for 90days. An additional negative control group of rats were fed with a rice-based AIN93G diet. Body weights, food intake, hematology, serum chemistry, serum hormone levels, sperm parameters and relative organ/body weights were measured, and gross as well as microscopic pathology were examined. No diet-related significant differences in the values of response variables were observed between rats that were fed with diet containing transgenic TT51, MingHui63 and the control in this 90-day feeding study. In addition, necropsy and histopathology examination indicated no treatment-related changes. The results from the present study indicated that TT51 does not appear to exert any effect on the reproductive system in male rats compared with MingHui63 or the control.

  17. Vancomycin MIC Does Not Predict 90-Day Mortality, Readmission, or Recurrence in a Prospective Cohort of Adults with Staphylococcus aureus Bacteremia

    PubMed Central

    Clemenzi-Allen, Angelo; Gahbauer, Alice; Deck, Daniel; Imp, Brandon; Vittinghoff, Eric; Chambers, Henry F.; Doernberg, Sarah

    2016-01-01

    Staphylococcus aureus bacteremia (SAB) is a tremendous health burden. Previous studies examining the association of vancomycin MIC and outcomes in patients with SAB have been inconclusive. This study evaluated the association between vancomycin MICs and 30- or 90-day mortality in individuals with SAB. This was a prospective cohort study of adults presenting from 2008 to 2013 with a first episode of SAB. Subjects were identified by an infection surveillance system. The main predictor was vancomycin MIC by MicroScan. The primary outcomes were death at 30 and 90 days, and secondary outcomes included recurrence, readmission, or a composite of death, recurrence, and readmission at 30 and 90 days. Covariates included methicillin susceptibility, demographics, illness severity, comorbidities, infectious source, and antibiotic use. Cox proportional-hazards models with propensity score adjustment were used to estimate 30- and 90-day outcomes. Of 429 unique first episodes of SAB, 11 were excluded, leaving 418 individuals for analysis. Eighty-three (19.9%) participants had a vancomycin MIC of 2 μg/ml. In the propensity-adjusted Cox model, a vancomycin MIC of 2 μg/ml compared to <2 μg/ml was not associated with a greater hazard of mortality or composite outcome of mortality, readmission, and recurrence at either 30 days (hazard ratios [HRs] of 0.86 [95% confidence interval {CI}, 0.41, 1.80] [P = 0.70] and 0.94 [95% CI, 0.55, 1.58] [P = 0.80], respectively) or 90 days (HRs of 0.91 [95% CI, 0.49, 1.69] [P = 0.77] and 0.69 [95% CI, 0.46, 1.04] [P = 0.08], respectively) after SAB diagnosis. In a prospective cohort of patients with SAB, vancomycin MIC was not associated with 30- or 90-day mortality or a composite of mortality, disease recurrence, or hospital readmission. PMID:27324762

  18. The development and succession of microbial communities in 90-day Bioregenerative Life Support Experiment in the Lunar Palace 1

    NASA Astrophysics Data System (ADS)

    Sun, Yi; Liu, Hong; Fu, Yuming; Liu, Bojie; Su, Qiang; Xie, Beizhen; Qin, Youcai; Dong, Chen; Liu, Guanghui

    Lunar Palace 1, as an integrative experiment facility for permanent astrobase life-support artificial closed ecosystem, is an artificial ecosystem which consists of plant cultivation, animal breeding and waste treatment units. It has been used to carry out a 90-day bioregenerative life support experiment with three crew members. Apparently, it’s hard to prevent the growth of microorganisms in such closed ecosystem for their strong adaptive capacity. Original microorganisms in the cabin, microbes in the course of loads delivery and the autologous microorganism by crew members and animals themselves are all the main source of the interior microorganisms, which may grow and regenerate in air, water and plants. Therefore, if these microorganisms could not be effectively monitored and controlled, it may cause microbial contamination and even lead to the unsteadiness of the whole closed ecosystem. In this study, the development and succession of the microbial communities of air, water system, plant system, and key facilities surfaces in Lunar Palace 1 were continuously monitored and analyzed by using plate counting method and molecular biological method during the 90-day experiment. The results were quite useful for the controlling of internal microorganisms and the safe operation of the whole system, and could also reveal the succession rules of microorganisms in an artificial closed ecosystem.

  19. 77 FR 45571 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To Delist the Green Turtle in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-01

    ...; 90-Day Finding on a Petition To Delist the Green Turtle in Hawaii and Notice of Status Review AGENCY...: We, NMFS, announce a 90-day finding on a petition to identify the Hawaiian population of the green... Species Act (ESA). The green turtle was listed under the ESA on July 28, 1978. Breeding populations of...

  20. 75 FR 67341 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Bay...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... Fish and Wildlife Service 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Bay Springs Salamander as Endangered AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of 90-day petition finding. SUMMARY: We, the U.S. Fish and Wildlife...

  1. 76 FR 61825 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List 29 Mollusk...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-05

    ... and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List 29 Mollusk Species as... CFR Part 17 Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List 29... term ``species'' to include ``any subspecies of fish or wildlife or plants, and any distinct...

  2. Ultrastructural response of rat lung to 90 days' exposure to oxygen at 450 mm Hg

    NASA Technical Reports Server (NTRS)

    Harrison, G. A.

    1974-01-01

    Young Sprague-Dawley rats were exposed to 100% oxygen at 450 mm Hg in constant environment capsules for 90 days. Lung tissue examined by electron microscopy revealed a number of changes, many similar to those observed after exposure to oxygen at 760 mm Hg for shorter periods of time. Alterations in vesicle size and number and in mitochondrial matrix and cristae appear in both the endothelial and epithelial cells. Blebbing and rarefication of cytoplasm occur in both cell layers of the alveolo-capillary wall. Also seen are fluid in the basement membrane, platelets in the capillaries, and alveolar fluid and debris. All of these alterations occur at 1 atm exposure. However, after exposure to 450 mm Hg the changes are not as widespread nor as destructive as they are at the higher pressure.

  3. Program operational summary: Operational 90 day manned test of a regenerative life support system

    NASA Technical Reports Server (NTRS)

    Jackson, J. K.; Wamsley, J. R.; Bonura, M. S.; Seeman, J. S.

    1972-01-01

    An operational 90-day manned test of a regenerative life support system was successfully completed. This test was performed with a crew of four carefully selected and trained men in a space station simulator (SSS) which had a two gas atmosphere maintained at a total pressure of 68.9, 10 psia, and composed of oxygen at a partial pressure of 3.05 psia with nitrogen as the diluent. The test was planned to provide data on regenerative life support subsystems and on integrated system operations in a closed ecology, similar to that of a space station. All crew equipment and expendables were stored onboard at the start of the mission to eliminate the need for pass-in operations. The significant accomplishments of the test, some of the pertinent test results, some of the problem areas, and conclusions are presented.

  4. Bioregenerative Life Support Experiment for 90-days in a Closed Integrative Experimental Facility LUNAR PALACE 1

    NASA Astrophysics Data System (ADS)

    Liu, Hong

    A 90-day bioregenerative life support experiment with three-member crew was carried out in the closed integrative experimental facility, LUNAR PALACE 1 regenerating basic living necessities and disposing wastes to provide life support for crew. It was composed of higher plant module, animal module, and waste treatment module. The higher plant module included wheat, chufa, pea, carrot and green leafy vegetables, with aim to satisfy requirement of 60% plant food and 100% O2 and water for crew. The yellow mealworm was selected as animal module to provide partial animal protein for crew, and reared on plant inedible biomass. The higher plant and yellow mealworm were both cultivated and harvested in the conveyor-type manner. The partial plant inedible biomass and human feces were mixed and co- fermented in the waste treatment module for preparation of soil-like substrate by bioconversion, maintaining gas balance and increasing closure degree. Meanwhile, in the waste treatment module, the water and partial nitrogen from human urine were recovered by physical-chemical means. Circulation of O2 and water as well as food supply from crops cultivated in the LUNAR PALACE 1 were investigated and calculated, and simultaneously gas exchange, mass flow among different components and system closure degree were also analyzed, respectively. Furthermore, the system robustness with respect to internal variation was tested and evaluated by sensitivity analysis of the aggregative index consisting of key performance indicators like crop yield, gaseous equilibrium concentration, microbial community composition, biogenic elements dynamics, etc., and comprehensively evaluating the operating state, to number change of crew from 2 to 4 during the 90-day closed experiment period.

  5. Pulmonary toxicity of simulated lunar and Martian dusts in mice: I. Histopathology 7 and 90 days after intratracheal instillation

    NASA Technical Reports Server (NTRS)

    Lam, Chiu-Wing; James, John T.; McCluskey, Richard; Cowper, Shawn; Balis, John; Muro-Cacho, Carlos

    2002-01-01

    O(3) and MSS coexposure appeared to be more than additive. Results for the TiO(2) and quartz controls were consistent with the known pulmonary toxicity of these compounds. The overall severity of lung injury was TiO(2) < LSS < MSS < O(3) + MSS < quartz. Except for TiO(2), the increased duration of dust presence in the lung from 7 to 90 days transformed the acute inflammatory response to a chronic inflammatory lesion. This study showed that LSS and MSS are more hazardous in the lungs than nuisance dusts.

  6. Pulmonary toxicity of simulated lunar and Martian dusts in mice: I. Histopathology 7 and 90 days after intratracheal instillation.

    PubMed

    Lam, Chiu-Wing; James, John T; McCluskey, Richard; Cowper, Shawn; Balis, John; Muro-Cacho, Carlos

    2002-09-01

    O(3) and MSS coexposure appeared to be more than additive. Results for the TiO(2) and quartz controls were consistent with the known pulmonary toxicity of these compounds. The overall severity of lung injury was TiO(2) < LSS < MSS < O(3) + MSS < quartz. Except for TiO(2), the increased duration of dust presence in the lung from 7 to 90 days transformed the acute inflammatory response to a chronic inflammatory lesion. This study showed that LSS and MSS are more hazardous in the lungs than nuisance dusts.

  7. Evaluation of 90 day repeated dose oral toxicity and reproductive/developmental toxicity of 3'-hydroxypterostilbene in experimental animals

    PubMed Central

    Majeed, Muhammed; Bani, Sarang; Natarajan, Sankaran; Pandey, Anjali; S, Naveed

    2017-01-01

    3'-Hydroxypterostilbene (3'-HPT) is one of the active constituents of Sphaerophysa salsula and Pterocarpus marsupium. Despite many proposed therapeutic applications, the safety profile of 3'-HPT has not been established. The present work investigated 90 day repeated oral dose and reproductive (developmental) toxicity of 3'-HPT as a test substance in rats as per OECD guidelines. 90 day toxicity was conducted in sixty Sprague Dawley rats of each sex (120 rats), grouped into six dosage groups of 0 (control), 0 (control recovery), 20 (low dose), 80 (mid dose), 200 (high dose) and 200 (high dose recovery) mg/kg bwt/day (body weight/day) respectively. For the reproductive toxicity study forty Wistar rats of each sex (80 rats) divided into four dosage groups received 0 (vehicle control), 20 (low dose), 100 (mid dose) and 200 (high dose) mg/kg bwt/day of 3'-HPT respectively for a period of two weeks while pre-mating, mating, on the day before sacrifice, in females during pregnancy and four days of lactation period. Results showed no significant differences in body weight, food intake, absolute organ weight, haematology, with no adverse effects (toxicity) on biochemical values nor any abnormal clinical signs or behavioural changes were observed in any of the control/treatment groups, including reproductive and developmental parameters, gross and histopathological changes. In conclusion, the results suggested a No-Observed-Adverse-Effect-Level (NOAEL) of 200 mg/kg bwt/day in rats after oral administration, implying 3'-HPT did not exhibit any toxicity under the study conditions employed. PMID:28257483

  8. Evaluation of 90 day repeated dose oral toxicity and reproductive/developmental toxicity of 3'-hydroxypterostilbene in experimental animals.

    PubMed

    Majeed, Muhammed; Bani, Sarang; Natarajan, Sankaran; Pandey, Anjali; S, Naveed

    2017-01-01

    3'-Hydroxypterostilbene (3'-HPT) is one of the active constituents of Sphaerophysa salsula and Pterocarpus marsupium. Despite many proposed therapeutic applications, the safety profile of 3'-HPT has not been established. The present work investigated 90 day repeated oral dose and reproductive (developmental) toxicity of 3'-HPT as a test substance in rats as per OECD guidelines. 90 day toxicity was conducted in sixty Sprague Dawley rats of each sex (120 rats), grouped into six dosage groups of 0 (control), 0 (control recovery), 20 (low dose), 80 (mid dose), 200 (high dose) and 200 (high dose recovery) mg/kg bwt/day (body weight/day) respectively. For the reproductive toxicity study forty Wistar rats of each sex (80 rats) divided into four dosage groups received 0 (vehicle control), 20 (low dose), 100 (mid dose) and 200 (high dose) mg/kg bwt/day of 3'-HPT respectively for a period of two weeks while pre-mating, mating, on the day before sacrifice, in females during pregnancy and four days of lactation period. Results showed no significant differences in body weight, food intake, absolute organ weight, haematology, with no adverse effects (toxicity) on biochemical values nor any abnormal clinical signs or behavioural changes were observed in any of the control/treatment groups, including reproductive and developmental parameters, gross and histopathological changes. In conclusion, the results suggested a No-Observed-Adverse-Effect-Level (NOAEL) of 200 mg/kg bwt/day in rats after oral administration, implying 3'-HPT did not exhibit any toxicity under the study conditions employed.

  9. Effects of furan on male rat reproduction parameters in a 90-day gavage study.

    PubMed

    Cooke, Gerard M; Taylor, Marnie; Bourque, Christine; Curran, Ivan; Gurofsky, Susan; Gill, Santokh

    2014-07-01

    Furan is produced in foods during processing and preservation techniques that involve heat treatment. Previously, we reported that furan-exposed rats exhibited dose-dependent gross and histological changes in liver which correlated with changes in liver serum enzymes ALT, AST and ALP. Here we report the effects of furan on the male reproductive system. There were no histological or weight changes in the reproductive organs. Serum testosterone levels were increased in a dose-dependent manner whereas serum LH was decreased. There were no changes in 17-OHase, 3β-HSD and 17β-HSD activities or serum FSH. Furan did not alter mRNA expression levels for the LH receptor or Tspo but in contrast, mRNA levels of StAR were increased in all doses of furan. The mRNA for the cholesterol side-chain cleavage enzyme (Cyp11a1) was increased by furan at the high dose, as was the level of intratesticular testosterone. We conclude that subchronic furan exposure affects testicular steroidogenesis.

  10. Effects of 30-, 60-, and 90-Day Bed Rest on Postural Control in Men and Women

    NASA Technical Reports Server (NTRS)

    Esteves, Julie; Taylor, Laura C.; Vanya, Robert D.; Dean, S. Lance; Wood, Scott J.

    2011-01-01

    INTRODUCTION Head-down-tilt bed rest (HDT) has been used as a safe gr ound-based analog to mimic and develop countermeasures for the physiological effects of spaceflight, including decrements in postural stability. The purpose of this investigation was to characterize the effects of 30-, 60-, and 90-day bed rest on postural control in men and women. METHODS Twenty-nine subjects (18M,11F) underwent 13 days of ambula tory acclimatization and were placed in 6? HDT for 30 (n=12), 60 (n=8), or 90 (n=9) days, followed by 14 days of ambulatory recovery. Computerized dynamic posturography (CDP) was used to assess changes in sensory and motor components of postural control, and recovery after HDT. Sensory Organization Tests (SOTs) objectively evaluate one?s ability to effectively use or suppress visual, vestibular, and proprioceptive information for postural control. Stability during the SOTs was assessed using peak-to-peak sway and convergence toward stability limits to derive an equilibrium score. Motor Control Tests (MCTs) evaluate one?s ability to recover from unexpected support surface perturbations, with performance determined by center-of-pressure path length. Whole-body kinematic data were collected to determine body-sway strategy used to maintain stability during each condition. Baselines were determined pre-HDT. Recovery was tracked post-HDT on days 0, 1, 2, and 4. RESULTS Immediately after HDT, subjects showed decreased performance on most SOTs, primarily on sway-referenced support conditions, typically returning to baseline levels within 4 days. MCT performance was not significantly affected. There were no significant gender or duration differences in performance. Kinematic data revealed a tendency to use ankle strategy to maintain an upright stance during most SOT conditions. Interestingly, six subjects (2M,4F) experienced orthostatic intolerance and were unable to complete day 0 testing. CONCLUSION HDT mimics some un loading mechanisms of spaceflight and

  11. Anatomical sector analysis of load-bearing tibial bone structure during 90-day bed rest and 1-year recovery.

    PubMed

    Cervinka, Tomas; Rittweger, Jörn; Hyttinen, Jari; Felsenberg, Dieter; Sievänen, Harri

    2011-07-01

    The aim of this study was to investigate whether the bone response to long bed rest-related immobility and during subsequent recovery differed at anatomically different sectors of tibial epiphysis and diaphysis. For this study, peripheral quantitative tomographic (pQCT) scans obtained from a previous 90-day 'Long Term Bed Rest' intervention were preprocessed with a new method based on statistical approach and re-analysed sector-wise. The pQCT was performed on 25 young healthy males twice before the bed rest, after the bed rest and after 1-year follow-up. All men underwent a strict bed rest intervention, and in addition, seven of them received pamidronate treatment and nine did flywheel exercises as countermeasures against disuse-related bone loss. Clearly, 3-9% sector-specific losses in trabecular density were observed at the tibial epiphysis on average. Similarly, cortical density decreased in a sector-specific way being the largest at the anterior sector of tibial diaphysis. During recovery, the bed rest-induced bone losses were practically restored and no consistent sector-specific modulation was observed in any subgroup. It is concluded that the sector-specific analysis of bone cross-sections has potential to reveal skeletal responses to various interventions that cannot be inferred from the average analysis of the whole bone cross-section. This approach is considered also useful for evaluating the bone responses from the biomechanical point of view.

  12. IN VIVO EVALUATION OF THE SEALING ABILITY OF TWO ENDODONTIC SEALERS IN ROOT CANALS EXPOSED TO THE ORAL ENVIRONMENT FOR 45 AND 90 DAYS

    PubMed Central

    Kopper, Patrícia Maria Poli; Vanni, José Roberto; Della Bona, Álvaro; de Figueiredo, José Antônio Poli; Porto, Sérgio

    2006-01-01

    This in vivo study evaluated the sealing ability of a resin-based sealer (AH Plus) and a zinc oxide-eugenol sealer (Endofill) in dogs' teeth, exposed to the oral environment for 45 and 90 days. Forty eight lower incisors from 8 dogs were endodonticaly treated. A stratified randomization determined the sealer use in each root canal. All canals were filled using the lateral condensation technique. The excess filling material at the cervical portion of the root canal was sectioned, leaving a 10-mm obturation length inside the canal. Teeth were provisionally sealed with glass ionomer cement for 24 h and the canals were exposed to the oral environment for either 45 or 90 days. Therefore, the experimental groups were as follows: A45- AH Plus for 45 days; A90- AH Plus for 90 days; E45- Endofill for 45 days; and E90- Endofill for 90 days (n=12). After the experimental period, the dogs were killed and the lower jaw was removed. The incisors were extracted and the roots were covered with two coats of nail varnish. The teeth were immersed in India ink for 96 h and submitted to diaphanization. Dye leakage (in mm) was measured using stereomicroscopy (10x magnification). The results were statistically analyzed using two-way ANOVA and Tukey test for multiple comparisons (á = 0.05). Group E90 (2.03±0.94) showed significantly higher mean leakage value than all other groups (p<0.001). None of the sealers, in both study conditions, were able to prevent dye leakage. PMID:19089029

  13. Influence of CO2 change during 90-day experiment on growth characteristics and photosynthetic activity in vegetables grown in Lunar Palace 1

    NASA Astrophysics Data System (ADS)

    Shao, Lingzhi; Liu, Hong; Wang, Minjuan; Fu, Yuming; Dong, Chen; Liu, Guanghui

    To establish bioregenerative life support system (BLSS) on lunar or Mars bases in the future, it is necessary to firstly conduct manned simulation experiments on the ground. For this purpose, Lunar palace 1 as an integrative experimental facility for permanent astrobase life support artificial closed ecosystem was set up, and 90-day experiment was carried out in this system. Vegtables as one of the important plant units, provide various nutrient content for crews in the system, such as vitamin, antioxidants and so on. However, it is not clear yet that how the CO _{2} change during 90-day experiment to affect on growth characteristics and photosynthetic activity in vegtables grown in the system. In this study, red lettuce, red rape, romaine lettuce, and bibb lettuce grown in the system were chosen as the subject investigated. Growth, expressed as dry weight, length of shoot and root, leaf area, was mearsured, and photosynthesis,expressed as net photosynthetic rate, intercellular CO _{2} concentration, chlorophyll contents and fluorescence was analyzed to detemind influence of CO _{2} change during 90-day experiment on growth in vegtables grown in the system.

  14. 76 FR 54423 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List All...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... on a Petition To List All Chimpanzees (Pan troglodytes) as Endangered AGENCY: Fish and Wildlife....S. Fish and Wildlife Service, announce a 90-day finding on a petition to list all chimpanzees (Pan... listing all chimpanzees as endangered may be warranted. Therefore, with the publication of this notice,...

  15. 75 FR 18782 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List Thorne's...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Fish and Wildlife Service 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List Thorne's Hairstreak Butterfly as Endangered Correction In Federal...

  16. 77 FR 54548 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Eagle...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-05

    ... [Docket No. FWS-R8-ES-2012-0072: 4500030113] Endangered and Threatened Wildlife and Plants; 90-Day Finding... species to, or removing a species from, the Federal Lists of Endangered and Threatened Wildlife and Plants... had had portions of their genome deliberately spliced with genes from another species...

  17. 78 FR 57611 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List Alabama Shad as...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-19

    ... 20, 2010, the Center for Biological Diversity (CBD), Alabama Rivers Alliance, Clinch Coalition... shad may be warranted. On April 28, 2011, in response to the negative 90-day finding, CBD filed a notice of intent to sue DOC and NMFS for alleged violations of the ESA in making its finding. CBD...

  18. 75 FR 41436 - Endangered and Threatened Wildlife; Notice of 90-Day Finding on a Petition to Revise Critical...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-16

    ... 90-Day Finding on a Petition to Revise Critical Habitat for the Endangered Leatherback Sea Turtle... endangered leatherback sea turtle under the Endangered Species Act (ESA). We find that the petition does not... leatherback sea turtles and their habitat under our jurisdiction. FOR FURTHER INFORMATION CONTACT:...

  19. 78 FR 41716 - Hours of Service; Limited 90-Day Waiver From the 30-Minute Rest Break Requirement for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-11

    ... beginning of this notice. Long-Range Weather Forecasts The FMCSA reviewed information from the National Oceanic and Atmospheric Administration's National Weather Service (NOAA). The NOAA posts long-range... Federal Motor Carrier Safety Administration 49 CFR Part 395 Hours of Service; Limited 90-Day Waiver...

  20. 78 FR 66675 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List Multiple Species of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-06

    ...; February 7, 1996). A species, subspecies, or DPS is ``endangered'' if it is in danger of extinction... extinction risk of concern for the species at issue. To make a 90-day finding on a petition to list a species.... Next, we evaluate whether the information indicates that the species at issue faces extinction...

  1. 76 FR 7820 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition to List the Texas Pipefish as...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... species, subspecies, or DPS is ``endangered'' if it is in danger of extinction throughout all or a... suggests an extinction risk of concern for the species at issue. To make a 90-day finding on a petition to... extinction risk that is cause for concern; this may be indicated in information expressly discussing...

  2. 76 FR 67401 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List All...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-01

    ... on a Petition To List All Chimpanzees (Pan troglodytes) as Endangered AGENCY: Fish and Wildlife... to list all chimpanzees (Pan troglodytes) as endangered under the Endangered Species Act of 1973, as... 54423) a 90-day finding on a petition to list all chimpanzees (Pan troglodytes) as endangered under...

  3. 78 FR 69376 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List 19 Species and 3...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ...We (NMFS) announce a 90-day finding on a petition to list 19 species and 3 subpopulations of sharks as threatened or endangered under the Endangered Species Act (ESA). We find that the petition presents substantial scientific or commercial information indicating that the petitioned action may be warranted for 9 species: Centrophorus harrissoni, Isogomphodon oxyrhynchus, Mustelus fasciatus,......

  4. 76 FR 55638 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Snowy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-08

    ... Fish and Wildlife Service 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; 90-Day Finding... Kansas; the southern Texas coast into northeast Mexico; and the central Mexican plateau) (AOU 1957, pp... of plants, and any distinct population segment of any species of vertebrate fish or wildlife...

  5. 75 FR 55730 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on Petitions To Delist the Gray...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-14

    ... Fish and Wildlife Service 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; 90-Day Finding... the 1973 Act, published in May 1974 (USDI 1974). A third gray wolf subspecies, the Mexican wolf (C. l... ``any species or subspecies of fish and wildlife or plants, and any distinct vertebrate...

  6. 75 FR 46894 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Mexican...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-04

    ... Fish and Wildlife Service 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Mexican Gray Wolf as an Endangered Subspecies With Critical Habitat AGENCY... finding on two petitions to list the Mexican gray wolf (Canis lupus baileyi) (Mexican wolf) as...

  7. Reliability Studies of Ceramic Capacitors.

    DTIC Science & Technology

    1984-10-01

    BaTiO 3, whose activation energy is composed more so of a mobility term. Figures 4.5c and d are activation energy plots for the Al+3 -doped BaTiO3...the mobility of the carrier. Figure 4.5f is an activation plot for BaTiO 3 which illustrates another important point. The activation energy is dependent... ACTIVATION ENERGY ............ 235 4.6 SUMMARY................................................. 240 4.7 FUTURE STUDIES

  8. Visual-motor response of crewmen during a simulated 90-day space mission as measured by the critical task battery

    NASA Technical Reports Server (NTRS)

    Allen, R. W.; Jex, H. R.

    1973-01-01

    In order to test various components of a regenerative life support system and to obtain data on the physiological and psychological effects of long duration exposure to confinement in a space station atmosphere, four carefully screened young men were sealed in a space station simulator for 90 days and administered a tracking test battery. The battery included a clinical test (Critical Instability Task) designed to measure a subject's dynamic time delay, and a more conventional steady tracking task, during which dynamic response (describing functions) and performance measures were obtained. Good correlation was noted between the clinical critical instability scores and more detailed tracking parameters such as dynamic time delay and gain-crossover frequency. The levels of each parameter span the range observed with professional pilots and astronaut candidates tested previously. The chamber environment caused no significant decrement on the average crewman's dynamic response behavior, and the subjects continued to improve slightly in their tracking skills during the 90-day confinement period.

  9. 77 FR 21920 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Eastern...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-12

    ...We, the U.S. Fish and Wildlife Service (Service), announce a 90-day finding on a petition to list either the Eastern population or the Southern Rocky Mountain (SRM) population of the boreal toad (Anaxyrus boreas boreas) as a distinct population segment (DPS) that is endangered or threatened under the Endangered Species Act of 1973, as amended (Act), and to designate critical habitat. Based on......

  10. Percutaneous reduction of mitral valve regurgitation using the MitraClip system - immediate and 90-day follow-up of 3 cases.

    PubMed

    Kübler, Piotr; Kustrzycka-Kratochwil, Dorota; Telichowski, Artur; Witkowski, Tomasz; Banasiak, Waldemar; Jankowska, Ewa A; Ponikowski, Piotr; Reczuch, Krzysztof

    2013-01-01

    Treatment of hemodynamically significant valvular heart diseases has been the domain of cardiac surgery for decades. However, a promising novel method is the MitraClip system, involving percutaneous connection of insufficient valve leaflets with special cobalt-chrome clips. Our study presents clinical characteristics, course of treatment with the MitraClip system, and immediate and 90-day clinical and echocardiographic follow-up of the first 3 patients treated in our institution. Subsequently, based on data from the literature and our own experience, the current position around the world, and the target group of patients who are most likely to benefit from treatment using the MitraClip system, are discussed.

  11. Flight control electronics reliability/maintenance study

    NASA Technical Reports Server (NTRS)

    Dade, W. W.; Edwards, R. H.; Katt, G. T.; Mcclellan, K. L.; Shomber, H. A.

    1977-01-01

    Collection and analysis of data are reported that concern the reliability and maintenance experience of flight control system electronics currently in use on passenger carrying jet aircraft. Two airlines B-747 airplane fleets were analyzed to assess the component reliability, system functional reliability, and achieved availability of the CAT II configuration flight control system. Also assessed were the costs generated by this system in the categories of spare equipment, schedule irregularity, and line and shop maintenance. The results indicate that although there is a marked difference in the geographic location and route pattern between the airlines studied, there is a close similarity in the reliability and the maintenance costs associated with the flight control electronics.

  12. MELD-Na as a prognostic indicator of 30- and 90-day mortality in patients with end-stage liver disease after creation of transjugular intrahepatic portosystemic shunt.

    PubMed

    Ahmed, Rezwan; Santhanam, Prasanna; Rayyan, Yaser

    2015-10-01

    Previous studies have shown that the Model for End-Stage Liver Disease (MELD) score is superior to other liver disease scoring systems to establish optimal candidates for transjugular intrahepatic portosystemic shunt (TIPS) procedure and liver transplantation. Our aim was to compare MELD-Na score with MELD score as a predictor of 30-day as well as 90-day mortality for individuals with end-stage liver disease (ESLD) after creation of TIPS. We performed a chart review on cirrhotic patients who underwent TIPS procedure and documented presence and severity of ascites and hepatic encephalopathy, patient laboratory values, and results from TIPS procedures. We compared continuous variables by Student's t-test for independent samples and categorical variables by χ-test(s). In non-normal distributions, a nonparametric test was used. We performed a logistic regression to determine the effects of several variables and analyzed variable predictors of likelihood of death within 30 and 90 days of TIPS procedure. Of the six predictor variables, only MELD-Na score was a statistically significant predictor of 30- and 90-day mortality following TIPS procedure for ESLD (P=0.028). For each one point increase in MELD-Na score, the odds of death increased by 1.15 times [95% confidence interval (1.02-1.30), P=0.28]. Since hyponatremia may be associated with poor prognostic features of overall health, its incorporation into the MELD scoring system to predict mortality in ESLD after creation of TIPS serves a useful purpose. Our single-center experience suggests that the MELD-Na score is the most effective predictor of survival after TIPS creation.

  13. Predictors of 30-Day Mortality and 90-Day Functional Recovery after Primary Intracerebral Hemorrhage : Hospital Based Multivariate Analysis in 585 Patients

    PubMed Central

    2009-01-01

    Objective The purpose of this study was to identify independent predictors of mortality and functional recovery in patients with primary intracerebral hemorrhage (PICH) and to improve functional outcome in these patients. Methods Data were collected retrospectively on 585 patients with supratentorial PICH admitted to the Stroke Unit at our hospital between 1st January 2004 and the 31st July 2008. Using multivariate logistic regression analysis, the associations between all selected variables and 30-day mortality and 90-day functional recoveries after PICH was evaluated. Results Ninety-day functional recovery was achieved in 29.1% of the 585 patients and 30-day mortality in 15.9%. Age (OR=7.384, p=0.000), limb weakness (OR=6.927, p=0.000), and hematoma volume (OR=5.293, p=0.000) were found to be powerful predictors of 90-day functional recovery. Furthermore, initial consciousness (OR=3.013, p=0.014) hematoma location (lobar, OR=2.653, p=0.003), ventricular extension of blood (OR=2.077, p=0.013), leukocytosis (OR=2.048, p=0.008), alcohol intake (drinker, OR=1.927, p=0.023), and increased serum aminotransferase (OR=1.892, p=0.035) were found to be independent predictors of 90-day functional recovery after PICH. On the other hand, a pupillary abnormality (OR=4.532, p=0.000) and initial unconsciousness (OR=3.362, p=0.000) were found to be independent predictors of 30-day mortality after PICH. Conclusion The predictors of mortality and functional recovery after PICH identified during this analysis may assist during clinical decision-making, when advising patients or family members about the prognosis of PICH and when planning intervention trials. PMID:19609417

  14. From goat colostrum to milk: physical, chemical, and immune evolution from partum to 90 days postpartum.

    PubMed

    Sánchez-Macías, D; Moreno-Indias, I; Castro, N; Morales-Delanuez, A; Argüello, A

    2014-01-01

    This study focused on the study of the changes originated in the milk from partum until d 90 of lactation. Ten multiparous Majorera goats, bred carefully under animal health standards, with a litter size of 2 kids (the average in this breed is 1.83 prolificacy) and similar gestation length (149 ± 1 d) were used. Goat kids were removed from their dams to avoid interferences with the study. Compositional content (fat, protein, and lactose) were measured, as well as some other properties, including pH, density, titratable acidity, ethanol stability, rennet clotting time, and somatic cell count. Moreover, immunity molecules (IgG, IgA, and IgM concentrations and chitotriosidase activity) received great attention. Fat and protein content were higher in the first days postpartum, whereas lactose content was lower. Density, titratable acidity, rennet clotting time, and somatic cell count decreased throughout the lactation period, whereas pH and ethanol stability increased. Relative to the immunological parameters, each measured parameter obtained its maximum level at d 0, showing the first milking as the choice to provide immunity to the newborn kids. On the other hand, this study might be used to establish what the best use is: processing or kid feeding.

  15. Toxicity of Carbon Nanotubes in the Lungs of Mice 7 and 90 Days After Intratracheal Instillation

    NASA Technical Reports Server (NTRS)

    Lam, Chiu-Wing; James, John T.; McCluskey, Richard; Hunter, Robert L.

    2002-01-01

    Single-walled carbon nanotubes have many potential applications in the electronic, computer, and aerospace industries. Because unprocessed nanotubes could become airborne and potentially reach the lungs, their pulmonary toxicity was investigated. The three products studied were made by different methods, and contained different types and amounts of residual catalytic metals. Mice were each intratracheally instilled once with 0,0.1 or 0.5 mg of nanotubes, a carbon black negative control, or a quartz positive control, and killed for histopathological study 7 d or 90 d after the treatment. All nanotube products induced epithelioid granulomas and, in some cases, interstitial inflammation in the animals of the 7 -d groups. These lesions persisted and were worse in the 90-d groups. We found that, if nanotubes reach the lung, they can be more toxic than quartz, which is considered a serious occupational health hazard in chronic inhalation exposures.

  16. Examining the nootropic effects of a special extract of Bacopa monniera on human cognitive functioning: 90 day double-blind placebo-controlled randomized trial.

    PubMed

    Stough, Con; Downey, Luke A; Lloyd, Jenny; Silber, Beata; Redman, Stephanie; Hutchison, Chris; Wesnes, Keith; Nathan, Pradeep J

    2008-12-01

    While Ayurvedic medicine has touted the cognitive enhancing effects of Bacopa monniera for centuries, there is a need for double-blind placebo-controlled investigations. One hundred and seven healthy participants were recruited for this double-blind placebo-controlled independent group design investigation. Sixty-two participants completed the study with 80% treatment compliance. Neuropsychological testing using the Cognitive Drug Research cognitive assessment system was conducted at baseline and after 90 days of treatment with a special extract of Bacopa monniera (2 x 150 mg KeenMind) or placebo. The Bacopa monniera product significantly improved performance on the 'Working Memory' factor, more specifically spatial working memory accuracy. The number of false-positives recorded in the Rapid visual information processing task was also reduced for the Bacopa monniera group following the treatment period. The current study provides support for the two other published studies reporting cognitive enhancing effects in healthy humans after a 90 day administration of the Bacopa monniera extract. Further studies are required to ascertain the effective dosage range, the time required to attain therapeutic levels and the effects over a longer term of administration.

  17. Cerebral Cortex Plasticity After 90 Days of Bed Rest: Data from TMS and fMRI

    PubMed Central

    Roberts, Donna R.; Ramsey, David; Johnson, Kevin; Kola, Jejo; Ricci, Raffaella; Hicks, Christian; Borckardt, Jeffrey J.; Bloomberg, Jacob J.; Epstein, Charles; George, Mark S.

    2010-01-01

    Introduction Microgravity animal models have demonstrated corticospinal plasticity; however, little is understood of its functional significance. In this pilot study, we explored corticospinal plasticity in a bed rest model. We hypothesized that the lack of weight bearing would induce cortical reorganization correlating with performance. Methods Four subjects underwent functional MRI (fMRI), transcranial magnetic stimulation (TMS), and functional mobility testing (FMT) before and after 90 d of bed rest. Recruitment curves (RC) were created by measuring motor evoked potentials over a range of TMS intensities with changes in the slope of the RC reflecting changes in corticospinal excitability. Results Significant leg RC slope decreases were observed on post-bed rest day 1 (P1) (t(2805) = −4.14, P < 0.0001), P2 (t(2805) = −6.59, P < 0.0001), P3 (t(2805) = −6.15, P < 0.0001), P5 (t(2805) = −7.93, P < 0.0001), P8 (t(2805) = −3.30, P = 0.001), and P12 (t(2805)= −3.33, P = 0.0009), suggesting a group decrease in corticospinal excitability in the immediate post-bed rest period with recovery approaching baseline over the following 2 wk. Significant effects were observed for hand RC slopes only for P2 (t(2916) = 1.97, P = 0.049), P3 (t(2916) = −2.12, P = 0.034), and P12 (t(2916) = −2.19, P = 0.029); no significant effects were observed for days P0 (t(2916) = −1.32, ns), P1 (t(2916) = 1.00, ns), P5 (t(2916) = −0.21, ns), or P8 (t(2916) = −0.27, ns). fMRI showed no change in activation for the hand but an increase in activation post-bed rest for the leg. On an individual basis, a more heterogeneous response was found which showed a potential association with performance on FMT. Discussion Results of this research include a better understanding of the cortical plasticity associated with leg disuse and may lead to applications in patient and astronaut rehabilitation. PMID:20058735

  18. Readmission Rate and Causes at 90-Day after Radical Cystectomy in Patients on Early Recovery after Surgery Protocol

    PubMed Central

    Altobelli, Emanuela; Buscarini, Maurizio; Gill, Harcharan S.; Skinner, Eila C.

    2017-01-01

    Background: Radical cystectomy (RC) is associated with high risk of early and late perioperative complications, and readmissions. The Enhanced Recovery After Surgery (ERAS) protocol has been applied to RC showing decreased hospital stay without increased morbidity. Objective: To evaluate the specific causes of hospital readmissions in RC patients treated before and after adoption of an ERAS protocol at our institution. Methods: We retrospectively evaluated the outcome of 207 RC patients on ERAS protocol at the Stanford University Hospital from January 2012 to December 2014. We focused on early (30-day) and late (90-day) postoperative readmission rate and causes. Results were compared with a pre-ERAS consecutive series of 177 RC patients from January 2009 to December 2011. Results: In the post-ERAS time period a total of 56 patients were readmitted, 41 within the first 30 days after surgery (20%) and 15 within the following 60 days (7%). Fever, often associated with dehydration, was the most common reason for presentation to the hospital, accounting for 57% of all readmissions. At 90 days infection accounted for 53% of readmissions. Of all the patients readmitted during the first 90 days after surgery, 32 had positive urine cultures, mostly caused by Enterococcus faecalis isolated in 18 (56%). Readmission rates did not increase since the introduction of the ERAS protocol, with an incidence of 27% in the post-ERAS group versus 30% in the pre-ERAS group. Conclusions: Despite accurate adherence to most recent perioperative antibiotic guidelines, the incidence of readmissions after RC due to infection still remains significant. PMID:28149935

  19. Readmission Rate and Causes at 90-Day after Radical Cystectomy in Patients on Early Recovery after Surgery Protocol.

    PubMed

    Altobelli, Emanuela; Buscarini, Maurizio; Gill, Harcharan S; Skinner, Eila C

    2017-01-27

    Background: Radical cystectomy (RC) is associated with high risk of early and late perioperative complications, and readmissions. The Enhanced Recovery After Surgery (ERAS) protocol has been applied to RC showing decreased hospital stay without increased morbidity. Objective: To evaluate the specific causes of hospital readmissions in RC patients treated before and after adoption of an ERAS protocol at our institution. Methods: We retrospectively evaluated the outcome of 207 RC patients on ERAS protocol at the Stanford University Hospital from January 2012 to December 2014. We focused on early (30-day) and late (90-day) postoperative readmission rate and causes. Results were compared with a pre-ERAS consecutive series of 177 RC patients from January 2009 to December 2011. Results: In the post-ERAS time period a total of 56 patients were readmitted, 41 within the first 30 days after surgery (20%) and 15 within the following 60 days (7%). Fever, often associated with dehydration, was the most common reason for presentation to the hospital, accounting for 57% of all readmissions. At 90 days infection accounted for 53% of readmissions. Of all the patients readmitted during the first 90 days after surgery, 32 had positive urine cultures, mostly caused by Enterococcus faecalis isolated in 18 (56%). Readmission rates did not increase since the introduction of the ERAS protocol, with an incidence of 27% in the post-ERAS group versus 30% in the pre-ERAS group. Conclusions: Despite accurate adherence to most recent perioperative antibiotic guidelines, the incidence of readmissions after RC due to infection still remains significant.

  20. Evolution of a 90-day model of care for bundled episodic payments for congestive heart failure in home care.

    PubMed

    Feld, April; Madden-Baer, Rose; McCorkle, Ruth

    2016-01-01

    The Centers for Medicare and Medicaid Services Innovation Center's Episode-Based Payment initiatives propose a large opportunity to reduce cost from waste and variation and stand to align hospitals, physicians, and postacute providers in the redesign of care that achieves savings and improve quality. Community-based organizations are at the forefront of this care redesign through innovative models of care aimed at bridging gaps in care coordination and reducing hospital readmissions. This article describes a community-based provider's approach to participation under the Bundled Payments for Care Improvement initiative and a 90-day model of care for congestive heart failure in home care.

  1. Training and certification program of the operating staff for a 90-day test of a regenerative life support system

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Prior to beginning a 90-day test of a regenerative life support system, a need was identified for a training and certification program to qualify an operating staff for conducting the test. The staff was responsible for operating and maintaining the test facility, monitoring and ensuring crew safety, and implementing procedures to ensure effective mission performance with good data collection and analysis. The training program was designed to ensure that each operating staff member was capable of performing his assigned function and was sufficiently cross-trained to serve at certain other positions on a contingency basis. Complicating the training program were budget and schedule limitations, and the high level of sophistication of test systems.

  2. Dietary and Food Processing for a 90-day Bioregenerative Life Support Experiment in the Lunar Palace 1

    NASA Astrophysics Data System (ADS)

    Zhao, Zhiruo; Fu, Yuming; Dong, Chen; Liu, Guanghui

    A 4-day cycle dietary menu was developed to meet the requirements of balanced diet of the crew within the 90-day closed experiment of bioregenerative life support in the Lunar Palace 1. The menu consisted of items prepared from crops and insect grown inside the system, as well as prestored food. Dairy recipe was composed of breads, vegetables, meats and soups, which provided about 2900 kcal per crew member per day. During food processing, to maximize nutrient recovery and minimize waste production, the whole wheat grains and chufa nuts were milled. Further, the carrot leaves and yellow mealworms were used as salad materials and bread ingredients, respectively. The sensory acceptability of the dishes in the menu was evaluated by flavor, texture, and appearance. Our results show that all dishes in the 4-day cycle menu were highly acceptable, which satisfies nutritional requirement of the crew members in the closed habitation.

  3. Distribution, elimination, and biopersistence to 90 days of a systemically introduced 30 nm ceria-engineered nanomaterial in rats.

    PubMed

    Yokel, Robert A; Au, Tu C; MacPhail, Robert; Hardas, Sarita S; Butterfield, D Allan; Sultana, Rukhsana; Goodman, Michael; Tseng, Michael T; Dan, Mo; Haghnazar, Hamed; Unrine, Jason M; Graham, Uschi M; Wu, Peng; Grulke, Eric A

    2012-05-01

    Nanoceria is used as a catalyst in diesel fuel, as an abrasive in printed circuit manufacture, and is being pursued as an antioxidant therapeutic. Our objective is to extend previous findings showing that there were no reductions of cerium in organs of the mononuclear phagocyte (reticuloendothelial) system up to 30 days after a single nanoscale ceria administration. An ~5% aqueous dispersion of citrate-stabilized 30 nm ceria, synthesized and characterized in-house, or vehicle, was iv infused into rats terminated 1, 7, 30, or 90 days later. Cageside observations were obtained daily, body weight weekly. Daily urinary and fecal cerium outputs were quantified for 2 weeks. Nine organs were weighed and samples collected from 14 tissues/organs/systems, blood and cerebrospinal fluid for cerium determination. Histology and oxidative stress were assessed. Less than 1% of the nanoceria was excreted in the first 2 weeks, 98% in feces. Body weight gain was initially impaired. Spleen weight was significantly increased in some ceria-treated groups, associated with abnormalities. Ceria was primarily retained in the spleen, liver, and bone marrow. There was little decrease of ceria in any tissue over the 90 days. Granulomas were observed in the liver. Time-dependent oxidative stress changes were seen in the liver and spleen. Nanoscale ceria was persistently retained by organs of the mononuclear phagocyte system, associated with adverse changes. The results support concern about the long-term fate and adverse effects of inert nanoscale metal oxides that distribute throughout the body, are persistently retained, and produce adverse changes.

  4. Assessing the Reliability of Beck Depression Inventory Scores: Reliability Generalization across Studies.

    ERIC Educational Resources Information Center

    Yin, Ping; Fan, Xitao

    2000-01-01

    Performed a meta-analysis of reliability estimates for Beck Depression Inventory (BDI) (A. Beck and others, 1961) scores across studies. Only 7.5% of studies reviewed (n=1,200) reported meaningful reliability estimates. Analysis results suggest that standard errors of measurement should be considered in addition to reliability estimates when…

  5. Secondary prevention lifestyle interventions initiated within 90 days after TIA or ‘minor’ stroke: a systematic review and meta-analysis of rehabilitation programmes

    PubMed Central

    Heron, Neil; Kee, Frank; Cardwell, Christopher; Tully, Mark A; Donnelly, Michael; Cupples, Margaret E

    2017-01-01

    Background Strokes are often preceded by a transient ischaemic attack (TIA) or ‘minor’ stroke. The immediate period after a TIA/minor stroke is a crucial time to initiate secondary prevention. However, the optimal approach to prevention, including non-pharmacological measures, after TIA is not clear. Aim To systematically review evidence about the effectiveness of delivering secondary prevention, with lifestyle interventions, in comprehensive rehabilitation programmes, initiated within 90 days of a TIA/minor stroke. Also, to categorise the specific behaviour change techniques used. Design and setting The review identified randomised controlled trials by searching the Cochrane Library, Ovid MEDLINE, Ovid EMBASE, Web of Science, EBSCO CINAHL and Ovid PsycINFO. Method Two review authors independently screened titles and abstracts for eligibility (programmes initiated within 90 days of event; outcomes reported for TIA/minor stroke) and extracted relevant data from appraised studies; a meta-analysis was used to synthesise the results. Results A total of 31 potentially eligible papers were identified and four studies, comprising 774 patients post-TIA or minor stroke, met the inclusion criteria; two had poor methodological quality. Individual studies reported increased aerobic capacity but meta-analysis found no significant change in resting and peak systolic blood pressure, resting heart rate, aerobic capacity, falls, or mortality. The main behaviour change techniques were goal setting and instructions about how to perform given behaviours. Conclusion There is limited evidence of the effectiveness of early post-TIA rehabilitation programmes with preventive lifestyle interventions. Further robust randomised controlled trials of comprehensive rehabilitation programmes that promote secondary prevention and lifestyle modification immediately after a TIA are needed. PMID:27919935

  6. Vertical jump performance after 90 days bed rest with and without flywheel resistive exercise, including a 180 days follow-up.

    PubMed

    Rittweger, Jörn; Felsenberg, Dieter; Maganaris, Constantinos; Ferretti, José Luis

    2007-07-01

    Muscle atrophy and neuromuscular de-conditioning occur in response to space flight and bed-rest. In this study, we investigated the efficacy of flywheel training to conserve jumping power and height during 90 days bed rest. Twenty-four young healthy men underwent strict bed-rest (-6 degrees head down tilt) for 90 days. Eight participants were assigned to a flywheel group (FW) and 16 to a control group (Ctrl). The ground reaction force was measured during vertical jump tests twice during baseline data collection, and on day 4, 7, 14, 90 and 180 of recovery. In half of the participants, jump tests were also performed within minutes after re-ambulation and on four more occasions during the first 2 days of recovery. Jump height was reduced from 40.6 cm (SD 6.1 cm) during the first baseline measurement to 27.6 cm (SD 5.6 cm) on day 4 of recovery in Ctrl, but only from 38.6 cm (SD 3.9 cm) to 34.4 cm (SD 6.5 cm) in FW (P < 0.001). At the same time, peak power was reduced from 47.4 W/kg (SD 8.0 W/kg) to 34.5 W/kg in Ctrl, but only from 46.2 W/kg (6.0 W/kg) to 42.2 W/kg SD 4.6 W/kg) in FW (P < 0.001). Jump height and peak power were completely recovered after 163 and 140 days in Ctrl, respectively, and after 72 and 18 days in FW (regression analysis). In conclusion, flywheel exercise could effectively offset neuromuscular de-conditioning during bed-rest, and led to full recovery at an earlier stage. These findings nourish the hope that adequate training paradigms can fully sustain neuromuscular function under microgravity conditions.

  7. An estimate of equatorial wave energy flux at 9- to 90-day periods in the Central Pacific

    NASA Technical Reports Server (NTRS)

    Eriksen, Charles C.; Richman, James G.

    1988-01-01

    Deep fluctuations in current along the equator in the Central Pacific are dominated by coherent structures which correspond closely to narrow-band propagating equatorial waves. Currents were measured roughly at 1500 and 3000 m depths at five moorings between 144 and 148 deg W from January 1981 to March 1983, as part of the Pacific Equatorial Ocean Dynamics program. In each frequency band resolved, a single complex empirical orthogonal function accounts for half to three quarters of the observed variance in either zonal or meridional current. Dispersion for equatorial first meridional Rossby and Rossby gravity waves is consistent with the observed vertical-zonal coherence structure. The observations indicate that energy flux is westward and downward in long first meridional mode Rossby waves at periods 45 days and longer, and eastward and downward in short first meridional mode Rossby waves and Rossby-gravity waves at periods 30 days and shorter. A local minimum in energy flux occurs at periods corresponding to a maximum in upper-ocean meridional current energy contributed by tropical instability waves. Total vertical flux across the 9- to 90-day period range is 2.5 kW/m.

  8. Physico-chemical properties of a novel (-)-hydroxycitric acid extract and its effect on body weight, selected organ weights, hepatic lipid peroxidation and DNA fragmentation, hematology and clinical chemistry, and histopathological changes over a period of 90 days.

    PubMed

    Shara, Michael; Ohia, Sunny E; Schmidt, Robert E; Yasmin, Taharat; Zardetto-Smith, Andrea; Kincaid, Anthony; Bagchi, Manashi; Chatterjee, Archana; Bagchi, Debasis; Stohs, Sidney J

    2004-05-01

    Garcinia cambogia-derived (-)-hydroxycitric acid (HCA) is a popular and natural supplement for weight management. HCA is a competitive inhibitor of the enzyme ATP citrate lyase, which catalyzes the conversion of citrate and coenzyme A to oxaloacetate and acetyl coenzyme A (acetyl CoA) in the cytosol. Acetyl CoA is used in the synthesis of fatty acids, cholesterol and triglycerides, and in the synthesis of acetylcholine in the central nervous system. Studies have demonstrated the efficacy of a novel 60% calcium-potassium salt of HCA derived from Garcinia cambogia (HCA-SX, Super CitriMax) in weight management. Results have shown that HCA-SX promotes fat oxidation, enhances serotonin release and availability in the brain cortex, normalizes lipid profiles, and lowers serum leptin levels in obese subjects. Acute oral, acute dermal, primary dermal irritation and primary eye irritation toxicity, as well as Ames bacterial reverse mutation studies and mouse lymphoma tests have demonstrated the safety of HCA-SX. However, no detailed long-term safety of HCA-SX or any other HCA extract has been previously assessed. We evaluated the dose- and time-dependent effects of HCA-SX in Sprague-Dawley rats on body weight, selected organ weights, hepatic lipid peroxidation and DNA fragmentation, hematology and clinical chemistry over a period of 90 days. Furthermore, a 90-day histopathological evaluation was conducted. The animals were treated with 0, 0.2, 2.0 and 5.0% HCA-SX of feed intake and were sacrificed on 30, 60 or 90 days of treatment. The body weight and selected organ weights were assessed and correlated as a % of body weight and brain weight at 90 days of treatment. A significant reduction in body weight was observed in treated rats as compared to control animals. An advancing age-induced marginal increase in hepatic lipid peroxidation was observed in both male and female rats, while no such difference in hepatic DNA fragmentation was observed as compared to the control

  9. Assessment of the reporting of quality and outcome measures in hepatic resections: a call for 90-day reporting in all hepatectomy series

    PubMed Central

    Egger, Michael E; Ohlendorf, Joanna M; Scoggins, Charles R; McMasters, Kelly M; Martin, Robert C G

    2015-01-01

    Background The aim of this paper is to assess the current state of quality and outcomes measures being reported for hepatic resections in the recent literature. Methods Medline and PubMed databases were searched for English language articles published between 1 January 2002 and 30 April 2013. Two examiners reviewed each article and relevant citations for appropriateness of inclusion, which excluded papers of liver donor hepatic resections, repeat hepatectomies or meta-analyses. Data were extracted and summarized by two examiners for analysis. Results Fifty-five studies were identified with suitable reporting to assess peri-operative mortality in hepatic resections. In only 35% (19/55) of the studies was the follow-up time explicitly stated, and in 47% (26/55) of studies peri-operative mortality was limited to in-hospital or 30 days. The time period in which complications were captured was not explicitly stated in 19 out of 28 studies. The remaining studies only captured complications within 30 days of the index operation (8/28). There was a paucity of quality literature addressing truly patient-centred outcomes. Conclusion Quality outcomes after a hepatic resection are inconsistently reported in the literature. Quality outcome studies for a hepatectomy should report mortality and morbidity at a minimum of 90 days after surgery. PMID:26228262

  10. Score Reliability: A Retrospective Look Back at 12 Years of Reliability Generalization Studies

    ERIC Educational Resources Information Center

    Vacha-Haase, Tammi; Thompson, Bruce

    2011-01-01

    The present study was conducted to characterize (a) the features of the thousands of primary reports synthesized in 47 reliability generalization (RG) measurement meta-analysis studies and (b) typical methodological practice within the RG literature to date. With respect to the treatment of score reliability in the literature, in an astounding…

  11. Evaluation of 90-day Repeated Dose Oral Toxicity, Glycometabolism, Learning and Memory Ability, and Related Enzyme of Chromium Malate Supplementation in Sprague-Dawley Rats.

    PubMed

    Feng, Weiwei; Wu, Huiyu; Li, Qian; Zhou, Zhaoxiang; Chen, Yao; Zhao, Ting; Feng, Yun; Mao, Guanghua; Li, Fang; Yang, Liuqing; Wu, Xiangyang

    2015-11-01

    Our previous study showed that chromium malate improved the regulation of blood glucose in mice with alloxan-induced diabetes. The present study was designed to evaluate the 90-day oral toxicity of chromium malate in Sprague-Dawley rats. The present study inspected the effect of chromium malate on glycometabolism, glycometabolism-related enzymes, lipid metabolism, and learning and memory ability in metabolically healthy Sprague-Dawley rats. The results showed that all rats survived and pathological, toxic, feces, and urine changes were not observed. Chromium malate did not cause measurable damage on liver, brain, and kidney. The fasting blood glucose, serum insulin, insulin resistance index, C-peptide, hepatic glycogen, glucose-6-phosphate dehydrogenase, glucokinase, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride levels of normal rats in chromium malate groups had no significant change when compared with control group and chromium picolinate group under physiologically relevant conditions. The serum and organ content of Cr in chromium malate groups had no significant change compared with control group. No significant changes were found in morris water maze test and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and true choline esterase (TChE) activity. The results indicated that supplementation with chromium malate did not cause measurable toxicity and has no obvious effect on glycometabolism and related enzymes, learning and memory ability, and related enzymes and lipid metabolism of female and male rats. The results of this study suggest that chromium malate is safe for human consumption.

  12. Collagen content in the vastus lateralis and the soleus muscle following a 90-day bed rest period with or without resistance exercises

    PubMed Central

    Nielsen, Rasmus Oestergaard; Schjerling, Peter; Tesch, Per; Stål, Per; Langberg, Henning

    2015-01-01

    Summary Introduction spaceflight seems associated with deterioration of the function of the skeletal muscles. Since muscle collagen is critical for muscle function, an improved understanding of the content of the muscle collagen during long-term inactivity seems important. Bed-rest with in-bed resistance training serves as a proxy for the conditions in space. Therefore, ground-based studies may improve the understanding of the consequences of long-term inactivity. Purpose the purpose is to compare the change in collagen protein in the vastus lateralis (VL) and the soleus (SOL) muscle amongst persons exposed to a 90-day bed rest with or without resistance exercise. Methods an explorative analysis was completed based on data from a randomized, controlled trial. The intervention group (BRE, SOL n=4, VL n=8) performed supine-based squat exercises, whereas the controls (BE, SOL n=6, VL n=12) remained inactive during follow-up. Muscle biopsies from vastus lateralis and soleus were taken at baseline (pre) and after 90-days’ follow-up (post). Muscle collagen (μg collagen/mg protein) was quantified. Two-way repeated measurements ANOVA was used to compare the interaction between the intervention (BRE/BR) and time (pre/post) for each muscle. Results the collagen content of VL was similar between pre and post in the BRE group (−3.8 μg collagen/mg protein [95% CI: −22.0; 14.4], p=0.68) while it rose amongst individuals in the BR group (14.9 μg collagen/mg protein [95% CI: −0.01; 29.7], p=0.05). The difference of 18.66 [95% CI: −6.5; 43.9] between BRE and BR across time was, however, not significant (p=0.14). No significant reduction in SOL muscle collagen content was observed from pre to post in the BR group (−9.3 μg collagen/mg protein [95% CI: −24.9; 6.4], p=0.25) or in the BRE group (−6.5 μg collagen/mg protein [95% CI: −25.6; 12.6], p=0.50). There was no difference in the effect of BR versus BRE over time (mean difference −2.78 μg collagen

  13. 90-Day Nose-Only Inhalation Toxicity Study of Trifluoroiodomethane (CG3I) to Male and Female Fischer Rats

    DTIC Science & Technology

    1996-02-01

    or 8% CF3I, minimal to mild atrophy of the testes and degeneration of spermatogonia in male rats exposed to 4 or 8% CF3I, and a mild m increase in...parameters included erythrocyte (RBC), leukocyte (WBC), differential leukocyte and platelet counts, hemoglobin (HGB), hematocrit (HCT), mean corpuscular... differentials were determined according to established procedures. Erythrocytes were enumerated on a Coulter counter (Coulter Electronics, Hialeah, FL

  14. Safety assessment of freeze-dried powdered Tenebrio molitor larvae (yellow mealworm) as novel food source: Evaluation of 90-day toxicity in Sprague-Dawley rats.

    PubMed

    Han, So-Ri; Lee, Byoung-Seok; Jung, Kyung-Jin; Yu, Hee-Jin; Yun, Eun-Young; Hwang, Jae Sam; Moon, Kyoung-Sik

    2016-06-01

    Worldwide demand for novel food source has grown and edible insects are a promising food sources for humans. Tenebrio molitor, as known as yellow mealworm, has advantages of being rich in protein, and easy to raise as a novel food source. The objective of this study was to evaluate subchronic toxicity, including potential hypersensitivity, of freeze-dried powdered T. molitor larvae (fdTML) in male and female Sprague-Dawley rats. The fdTML was administered orally once daily at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 90 days. A toxicological assessment was performed, which included mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings, histopathologic examination and allergic reaction. There were no fdTML- related findings in clinical signs, urinalysis, hematology and serum chemistry, gross examination, histopathologic examination or allergic reaction. In conclusion, the No Observed Adverse Effect Level (NOAEL) for fdTML was determined to be in excess of 3000 mg/kg/day in both sexes of rats under the experimental conditions of this study.

  15. Selected reliability studies for the NERVA program

    NASA Technical Reports Server (NTRS)

    Hoover, S. V.; Murphy, R. J.; Nowak, W. B.; Sexton, R. W.

    1974-01-01

    An investigation was made into certain methods of reliability analysis that are particularly suitable for complex mechanisms or systems in which there are many interactions. The methods developed were intended to assist in the design of such mechanisms, especially for analysis of failure sensitivity to parameter variations and for estimating reliability where extensive and meaningful life testing is not feasible. The system is modeled by a network of interconnected nodes. Each node is a state or mode of operation, or is an input or output node, and the branches are interactions. The network, with its probabilistic and time-dependent paths is also analyzed for reliability and failure modes by a Monte Carlo, computerized simulation of system performance.

  16. A 90 day safety assessment of genetically modified rice expressing Cry1Ab/1Ac protein using an aquatic animal model.

    PubMed

    Zhu, Hao-Jun; Chen, Yi; Li, Yun-He; Wang, Jia-Mei; Ding, Jia-Tong; Chen, Xiu-Ping; Peng, Yu-Fa

    2015-04-15

    In fields of transgenic Bt rice, frogs are exposed to Bt proteins through consumption of both target and nontarget insects. In the present study, we assessed the risk posed by transgenic rice expressing a Cry1Ab/1Ac fusion protein (Huahui 1, HH1) on the development of Xenopus laevis. For 90 days, froglets were fed a diet with 30% HH1 rice, 30% parental rice (Minghui 63, MH63), or no rice as a control. Body weight and length were measured every 15 days. After sacrificing the froglets, we performed a range of biological, clinical, and pathological assessments. No significant differences were found in body weight (on day 90: 27.7 ± 2.17, 27.4 ± 2.40, and 27.9 ± 1.67 g for HH1, MH63, and control, respectively), body length (on day 90: 60.2 ± 1.55, 59.3 ± 2.33, and 59.7 ± 1.64 mm for HH1, MH63, and control, respectively), animal behavior, organ weight, liver and kidney function, or the microstructure of some tissues between the froglets fed on the HH1-containing diet and those fed on the MH63-containing or control diets. This indicates that frog development was not adversely affected by dietary intake of Cry1Ab/1Ac protein.

  17. Studying Reliability Using Identical Handheld Lactate Analyzers

    ERIC Educational Resources Information Center

    Stewart, Mark T.; Stavrianeas, Stasinos

    2008-01-01

    Accusport analyzers were used to generate lactate performance curves in an investigative laboratory activity emphasizing the importance of reliable instrumentation. Both the calibration and testing phases of the exercise provided students with a hands-on opportunity to use laboratory-grade instrumentation while allowing for meaningful connections…

  18. Dose- and time-dependent effects of a novel (-)-hydroxycitric acid extract on body weight, hepatic and testicular lipid peroxidation, DNA fragmentation and histopathological data over a period of 90 days.

    PubMed

    Shara, Michael; Ohia, Sunny E; Yasmin, Taharat; Zardetto-Smith, Andrea; Kincaid, Anthony; Bagchi, Manashi; Chatterjee, Archana; Bagchi, Debasis; Stohs, Sidney J

    2003-12-01

    (-)-Hydroxycitric acid (HCA), a natural extract from the dried fruit rind of Garcinia cambogia (family Guttiferae), is a popular supplement for weight management. The dried fruit rind has been used for centuries as a condiment in Southeastern Asia to make food more filling and satisfying. A significant number of studies highlight the efficacy of Super CitriMax (HCA-SX, a novel 60% calcium-potassium salt of HCA derived from Garcinia cambogia) in weight management. These studies also demonstrate that HCA-SX promotes fat oxidation, inhibits ATP-citrate lyase (a building block for fat synthesis), and lowers the level of leptin in obese subjects. Acute oral, acute dermal, primary dermal irritation and primary eye irritation toxicity studies have demonstrated the safety of HCA-SX. However, no long-term safety of HCA-SX or any other (-)-hydroxycitric acid extract has been previously assessed. In this study, we have evaluated the dose- and time-dependent effects of HCA-SX in Sprague-Dawley rats on body weight, hepatic and testicular lipid peroxidation, DNA fragmentation, liver and testis weight, expressed as such and as a % of body weight and brain weight, and histopathological changes over a period of 90 days. The animals were treated with 0, 0.2, 2.0 and 5.0% HCA-SX as feed intake and the animals were sacrificed on 30, 60 or 90 days of treatment. The feed and water intake were assessed and correlated with the reduction in body weight. HCA-SX supplementation demonstrated a reduction in body weight in both male and female rats over a period of 90 days as compared to the corresponding control animals. An advancing age-induced marginal increase in hepatic lipid peroxidation was observed in both male and female rats as compared to the corresponding control animals. However, no such difference in hepatic DNA fragmentation and testicular lipid peroxidation and DNA fragmentation was observed. Furthermore, liver and testis weight, expressed as such and as a percentage of body

  19. Studying reliability using identical handheld lactate analyzers.

    PubMed

    Stewart, Mark T; Stavrianeas, Stasinos

    2008-06-01

    Accusport analyzers were used to generate lactate performance curves in an investigative laboratory activity emphasizing the importance of reliable instrumentation. Both the calibration and testing phases of the exercise provided students with a hands-on opportunity to use laboratory-grade instrumentation while allowing for meaningful connections to be made between data collection and analysis. Pairs of student teams tested individual aerobically trained participants exercising to voluntary exhaustion on a cycle ergometer. The analysis of four volunteers' postexercise blood samples revealed lactate data that, although highly correlated, showed small but statistically significant differences between devices. This laboratory activity provides a useful platform for introducing students to the reliability of instrumentation, in particular noting its relevance to designs employing repeated measures.

  20. 7 CFR Appendix B to Subpart C of... - FSA-2510, Notice of Availability of Loan Servicing to Borrowers Who Are 90 Days Past Due

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false FSA-2510, Notice of Availability of Loan Servicing to Borrowers Who Are 90 Days Past Due B Appendix B to Subpart C of Part 766 Agriculture Regulations of the... LOAN SERVICING-SPECIAL Loan Servicing Programs Pt. 766, Subpt. C, App. B Appendix B to Subpart C...

  1. 7 CFR Appendix B to Subpart C of... - FSA-2510, Notice of Availability of Loan Servicing to Borrowers Who Are 90 Days Past Due

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false FSA-2510, Notice of Availability of Loan Servicing to Borrowers Who Are 90 Days Past Due B Appendix B to Subpart C of Part 766 Agriculture Regulations of the... LOAN SERVICING-SPECIAL Loan Servicing Programs Pt. 766, Subpt. C, App. B Appendix B to Subpart C...

  2. Long life reliability thermal control systems study

    NASA Technical Reports Server (NTRS)

    Scollon, T. R., Jr.; Killen, R. E.

    1972-01-01

    The results of a program undertaken to conceptually design and evaluate a passive, high reliability, long life thermal control system for space station application are presented. The program consisted of four steps: (1) investigate and select potential thermal system elements; (2) conceive, evaluate and select a thermal control system using these elements; (3) conduct a verification test of a prototype segment of the selected system; and (4) evaluate the utilization of waste heat from the power supply. The result of this project is a conceptual thermal control system design which employs heat pipes as primary components, both for heat transport and temperature control. The system, its evaluation, and the test results are described.

  3. Azurin for Biomolecular Electronics: a Reliability Study

    NASA Astrophysics Data System (ADS)

    Bramanti, Alessandro; Pompa, Pier Paolo; Maruccio, Giuseppe; Calabi, Franco; Arima, Valentina; Cingolani, Roberto; Corni, Stefano; Di Felice, Rosa; De Rienzo, Francesca; Rinaldi, Ross

    2005-09-01

    The metalloprotein azurin, used in biomolecular electronics, is investigated with respect to its resilience to high electric fields and ambient conditions, which are crucial reliability issues. Concerning the effect of electric fields, two models of different complexity agree indicating an unexpectedly high robustness. Experiments in device-like conditions confirm that no structural modifications occur, according to fluorescence spectra, even after a 40-min exposure to tens of MV/m. Ageing is then investigated experimentally, at ambient conditions and without field, over several days. Only a small conformational rearrangement is observed in the first tens of hours, followed by an equilibrium state.

  4. Measuring eating disorder attitudes and behaviors: a reliability generalization study

    PubMed Central

    2014-01-01

    Background Although score reliability is a sample-dependent characteristic, researchers often only report reliability estimates from previous studies as justification for employing particular questionnaires in their research. The present study followed reliability generalization procedures to determine the mean score reliability of the Eating Disorder Inventory and its most commonly employed subscales (Drive for Thinness, Bulimia, and Body Dissatisfaction) and the Eating Attitudes Test as a way to better identify those characteristics that might impact score reliability. Methods Published studies that used these measures were coded based on their reporting of reliability information and additional study characteristics that might influence score reliability. Results Score reliability estimates were included in 26.15% of studies using the EDI and 36.28% of studies using the EAT. Mean Cronbach’s alphas for the EDI (total score = .91; subscales = .75 to .89), EAT-40 (total score = .81) and EAT-26 (total score = .86; subscales = .56 to .80) suggested variability in estimated internal consistency. Whereas some EDI subscales exhibited higher score reliability in clinical eating disorder samples than in nonclinical samples, other subscales did not exhibit these differences. Score reliability information for the EAT was primarily reported for nonclinical samples, making it difficult to characterize the effect of type of sample on these measures. However, there was a tendency for mean score reliability to be higher in the adult (vs. adolescent) samples and in female (vs. male) samples. Conclusions Overall, this study highlights the importance of assessing and reporting internal consistency during every test administration because reliability is affected by characteristics of the participants being examined. PMID:24764530

  5. Assessment of the safety of hydrogenated resistant maltodextrin: reverse mutation assay, acute and 90-day subchronic repeated oral toxicity in rats, and acute no-effect level for diarrhea in humans.

    PubMed

    Yoshikawa, Yuko; Kishimoto, Yuka; Tagami, Hiroyuki; Kanahori, Sumiko

    2013-01-01

    A series of safety assessments were performed on hydrogenated resistant maltodextrin prepared by converting the reducing terminal glucose of resistant maltodextrin into sorbitol. The reverse mutation assay did not show mutagenicity. Acute and 90-day subchronic oral toxicity studies in rats showed no death was observed in any groups, including the group receiving the highest single dose of 10 g/kg body weight or the highest dose of 5 g/kg body weight per day for 90 days. Mucous or watery stools were observed in the hydrogenated resistant maltodextrin treatment group on the acute study, which were transient and were associated with the osmotic pressure caused by intake of the high concentrations. Subchronic study showed dose-dependent increases in the weights of cecum alone, cecal contents alone, and cecum with cecal contents as well as hypertrophy of the cecal mucosal epithelium, which are considered to be common physiological responses after intake of indigestible carbohydrates. These results indicated that the no observed adverse effect level (NOAEL) of hydrogenated resistant maltodextrin was 10 g/kg body weight or more on the acute oral toxicity study and 5.0 g/kg body weight/day or more on the 90-day subchronic repeated oral toxicity study in rats. Further study performed in healthy adult humans showed that the acute no-effect level of hydrogenated resistant maltodextrin for diarrhea was 0.8 g/kg body weight for men and more than 1.0 g/kg body weight for women. The results of the current safety assessment studies suggest that hydrogenated resistant maltodextrin is safe for human consumption.

  6. The 747 primary flight control systems reliability and maintenance study

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The major operational characteristics of the 747 Primary Flight Control Systems (PFCS) are described. Results of reliability analysis for separate control functions are presented. The analysis makes use of a NASA computer program which calculates reliability of redundant systems. Costs for maintaining the 747 PFCS in airline service are assessed. The reliabilities and cost will provide a baseline for use in trade studies of future flight control system design.

  7. A New Tissue Resonator Indenter Device and Reliability Study

    PubMed Central

    Jia, Ming; Zu, Jean W.; Hariri, Alireza

    2011-01-01

    Knowledge of tissue mechanical properties is widely required by medical applications, such as disease diagnostics, surgery operation, simulation, planning, and training. A new portable device, called Tissue Resonator Indenter Device (TRID), has been developed for measurement of regional viscoelastic properties of soft tissues at the Bio-instrument and Biomechanics Lab of the University of Toronto. As a device for soft tissue properties in-vivo measurements, the reliability of TRID is crucial. This paper presents TRID’s working principle and the experimental study of TRID’s reliability with respect to inter-reliability, intra-reliability, and the indenter misalignment effect as well. PMID:22346623

  8. 78 FR 10601 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition to List 44 Species of Corals as...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-14

    ... cycle and include the order Anthoathecatae (hydrocorals). To date, 134 unique coral taxa have been found... role in the distribution of Alaska coral species, including nutrient flows and productivity, water... directly and indirectly affect cold water corals, yet no empirical studies to date have...

  9. Effects of genetically modified T2A-1 rice on the GI health of rats after 90-day supplement.

    PubMed

    Yuan, Yanfang; Xu, Wentao; He, Xiaoyun; Liu, Haiyan; Cao, Sishuo; Qi, Xiaozhe; Huang, Kunlun; Luo, Yunbo

    2013-01-01

    Bacillus thuringiensis insecticidal toxin (Bt) rice will be commercialized as a main food source. Traditional safety assessments on genetically modified products pay little attention on gastrointestinal (GI) health. More data about GI health of Bt rice must be provided to dispel public' doubts about the potential effects on human health. We constructed an improved safety assessment animal model using a basic subchronic toxicity experiment, measuring a range of parameters including microflora composition, intestinal permeability, epithelial structure, fecal enzymes, bacterial activity, and intestinal immunity. Significant differences were found between rice-fed groups and AIN93G-fed control groups in several parameters, whereas no differences were observed between genetically modified and non-genetically modified groups. No adverse effects were found on GI health resulting from genetically modified T2A-1 rice. In conclusion, this study may offer a systematic safety assessment model for GM material with respect to the effects on GI health.

  10. Effects of genetically modified T2A-1 rice on the GI health of rats after 90-day supplement

    PubMed Central

    Yuan, Yanfang; Xu, Wentao; He, Xiaoyun; Liu, Haiyan; Cao, Sishuo; Qi, Xiaozhe; Huang, Kunlun; Luo, Yunbo

    2013-01-01

    Bacillus thuringiensis insecticidal toxin (Bt) rice will be commercialized as a main food source. Traditional safety assessments on genetically modified products pay little attention on gastrointestinal (GI) health. More data about GI health of Bt rice must be provided to dispel public' doubts about the potential effects on human health. We constructed an improved safety assessment animal model using a basic subchronic toxicity experiment, measuring a range of parameters including microflora composition, intestinal permeability, epithelial structure, fecal enzymes, bacterial activity, and intestinal immunity. Significant differences were found between rice-fed groups and AIN93G-fed control groups in several parameters, whereas no differences were observed between genetically modified and non-genetically modified groups. No adverse effects were found on GI health resulting from genetically modified T2A-1 rice. In conclusion, this study may offer a systematic safety assessment model for GM material with respect to the effects on GI health. PMID:23752350

  11. Pulmonary toxicity of single-wall carbon nanotubes in mice 7 and 90 days after intratracheal instillation

    NASA Technical Reports Server (NTRS)

    Lam, Chiu-Wing; James, John T.; McCluskey, Richard; Hunter, Robert L.

    2004-01-01

    Nanomaterials are part of an industrial revolution to develop lightweight but strong materials for a variety of purposes. Single-wall carbon nanotubes are an important member of this class of materials. They structurally resemble rolled-up graphite sheets, usually with one end capped; individually they are about 1 nm in diameter and several microns long, but they often pack tightly together to form rods or ropes of microscopic sizes. Carbon nanotubes possess unique electrical, mechanical, and thermal properties and have many potential applications in the electronics, computer, and aerospace industries. Unprocessed nanotubes are very light and could become airborne and potentially reach the lungs. Because the toxicity of nanotubes in the lung is not known, their pulmonary toxicity was investigated. The three products studied were made by different methods and contained different types and amounts of residual catalytic metals. Mice were intratracheally instilled with 0, 0.1, or 0.5 mg of carbon nanotubes, a carbon black negative control, or a quartz positive control and euthanized 7 d or 90 d after the single treatment for histopathological study of the lungs. All nanotube products induced dose-dependent epithelioid granulomas and, in some cases, interstitial inflammation in the animals of the 7-d groups. These lesions persisted and were more pronounced in the 90-d groups; the lungs of some animals also revealed peribronchial inflammation and necrosis that had extended into the alveolar septa. The lungs of mice treated with carbon black were normal, whereas those treated with high-dose quartz revealed mild to moderate inflammation. These results show that, for the test conditions described here and on an equal-weight basis, if carbon nanotubes reach the lungs, they are much more toxic than carbon black and can be more toxic than quartz, which is considered a serious occupational health hazard in chronic inhalation exposures.

  12. Spent Nuclear Fuel Transport Reliability Study

    SciTech Connect

    Wang, Jy-An John; Wang, Hong; Jiang, Hao

    2016-01-01

    This conference paper was orignated and shorten from the following publisehd PTS documents: 1. Jy-An Wang, Hao Jiang, and Hong Wang, Dynamic Deformation Simulation of Spent Nuclear Fuel Assembly and CIRFT Deformation Sensor Stability Investigation, ORNL/SPR-2015/662, November 2015. 2. Jy-An Wang, Hong Wang, Mechanical Fatigue Testing of High-Burnup Fuel for Transportation Applications, NUREG/CR-7198, ORNL/TM-2014/214, May 2015. 3. Jy-An Wang, Hong Wang, Hao Jiang, Yong Yan, Bruce Bevard, Spent Nuclear Fuel Vibration Integrity Study 16332, WM2016 Conference, March 6 10, 2016, Phoenix, Arizona.

  13. Sensitivity Study for Long Term Reliability

    NASA Technical Reports Server (NTRS)

    White, Allan L.

    2008-01-01

    This paper illustrates using Markov models to establish system and maintenance requirements for small electronic controllers where the goal is a high probability of continuous service for a long period of time. The system and maintenance items considered are quality of components, various degrees of simple redundancy, redundancy with reconfiguration, diagnostic levels, periodic maintenance, and preventive maintenance. Markov models permit a quantitative investigation with comparison and contrast. An element of special interest is the use of conditional probability to study the combination of imperfect diagnostics and periodic maintenance.

  14. Emergency Locator Transmitter Survivability and Reliability Study

    NASA Technical Reports Server (NTRS)

    Stimson, Chad M.; Littell, Justin D.; Mazzuca, Lisa M.; Foster, Anthony W.; Theodorakos, George J.

    2017-01-01

    A comprehensive study of Emergency Locator Transmitter (ELT) performance was conducted over a three year period concluding in 2016 in support of the Search and Rescue (SAR) Mission Office at National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC). The study began with a review of reported performance cited in a collection of works published as early as 1980 as well as analysis of a focused set of contemporary aviation crash reports. Based on initial research findings, a series of subscale and fullscale system tests were performed at NASA Langley Research Center (LaRC) with the goals of investigating ELT system failure modes and developing recommended improvements to the Radio Technical Commission for Aeronautics (RTCA) Minimum Operational Performance Specification (MOPS) that will result in improved system performance. Enhanced performance of ELT systems in aviation accidents will reduce unnecessary loss of human life and make SAR operations safer and less costly by reducing the amount of time required to locate accident sites.

  15. Bioaccumulation and locomotor effects of manganese sulfate in Sprague-Dawley rats following subchronic (90 days) inhalation exposure

    SciTech Connect

    Tapin, Danielle; Kennedy, Greg; Lambert, Jean; Zayed, Joseph . E-mail: joseph.zayed@umontreal.ca

    2006-03-01

    Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic compound that was introduced as an antiknock additive to replace lead in unleaded fuel. The combustion of MMT results in the emission of fine Mn particulates mainly in the form of manganese sulfate and manganese phosphate. The objective of this study is to determine the effects of subchronic exposure to Mn sulfate in different tissues, on locomotor activity, on neuropathology, and on blood serum biochemical parameters. A control group and three groups of 30 male Sprague-Dawley rats were exposed 6-h/day, 5 days/week for 13 consecutive weeks at 30, 300, or 3000 {mu}g/m{sup 3} Mn sulfate. Locomotor activity was measured during 36 h using an Auto-Track System. Blood and the following tissues were collected and analyzed for manganese content by neutron activation analysis: olfactory bulb, globus pallidus, caudate/putamen, cerebellum, frontal cortex, liver, lung, testis, and kidney. Neuronal cell counts were obtained for the caudate/putamen and the globus pallidus and clinical biochemistry was assessed. Manganese concentrations were increased in blood, kidney, lung, and testis and in all brain regions in the 3000 {mu}g/m{sup 3} exposure group. Significant differences were also noted in the 300 {mu}g/m{sup 3} exposure group. Neuronal cell counts for the globus pallidus were significantly different between the two highest exposed groups and the controls. Locomotor activity for all exposure concentrations and resting time for the middle and highest concentrations for the two night resting periods were significantly increased. Total ambulatory count was decreased significantly for all exposure concentrations. Biochemical profiles also presented significant differences. No body weight loss was observed between all groups. These results suggest that neurotoxicity could occur at low exposure levels of Mn sulfate, one of the main combustion products of MMT.

  16. STS-90 Day 09 Highlights

    NASA Technical Reports Server (NTRS)

    1998-01-01

    On this ninth day of the STS-90 mission, the sleep period of the flight crew, Cmdr. Richard A. Searfoss, Pilot Scott D. Altman, and Mission Specialists Richard M. Linnehan, Dafydd Rhys Williams and Kathryn P. Hire, and Payload Specialists Jay C. Buckey and James A. Pawelczyk, is interrupted due to problems with equipment that removes carbon dioxide from the cabin atmosphere. Because of this, Columbia's crew went to bed about two hours later than scheduled.

  17. STS-90 Day 04 Highlights

    NASA Technical Reports Server (NTRS)

    1998-01-01

    On this forth day of the STS-90 mission, the flight crew, Cmdr. Richard A. Searfoss, Pilot Scott D. Altman, and Mission Specialists Richard M. Linnehan, Dafydd Rhys Williams and Kathryn P. Hire, and Payload Specialists Jay C. Buckey and James A. Pawelczyk continue work with the Escher Staircase Behavior Testing of Adult Rats experiment. This is the first of two behavior testing sessions with the adult rats being used for this experiment. The rats will have a 'hyper drive' unit placed on their head which has recording electrodes made of microscopic wires that are positioned in the brain to record activity in the hippocampus. The hippocampus is that portion of the brain used to develop spatial maps to help us navigate from one place to the other. With the 'hyper drive' units in place, the rats will then be put through a maze or on a track. While the rat is maneuvering on the maze or track, the cell activity of the hippocampus will be measured and recorded.

  18. STS-90 Day 14 Highlights

    NASA Technical Reports Server (NTRS)

    1998-01-01

    On this fourteenth day of the STS-90 mission, the flight crew, Cmdr. Richard A. Searfoss, Pilot Scott D. Altman, and Mission Specialists Richard M. Linnehan, Dafydd Rhys Williams and Kathryn P. Hire, and Payload Specialists Jay C. Buckey and James A. Pawelczyk focus on the efforts of Neurolab's Neuronal Plasticity Team to better understand how the adult nervous system adapts to the new environment of space. Columbia's science crew -- Mission Specialists Rick Linnehan and Dave Williams and Payload Specialists Jay Buckey and Jim Pawelczyk -- perform the second and final in-flight dissections of the adult male rats on board. The crew euthanizes and dissects nine rats and remove the vestibular or balance organs of the inner ear; the cerebellum, the part of the brain critical for maintaining balance and for processing information from the limbs so they can be moved smoothly; and the cerebrum, one part of which controls automatic functions such as body temperature regulation and the body's internal clock, and the cortical region that controls cognitive functions such as thinking. The first dissection, which was performed on the second day of the flight, went extremely well, according to Neurolab scientists.

  19. Reliability studies of integrated modular engine system designs

    NASA Technical Reports Server (NTRS)

    Hardy, Terry L.; Rapp, Douglas C.

    1993-01-01

    A study was performed to evaluate the reliability of Integrated Modular Engine (IME) concepts. Comparisons were made between networked IME systems and non-networked discrete systems using expander cycle configurations. Both redundant and non-redundant systems were analyzed. Binomial approximation and Markov analysis techniques were employed to evaluate total system reliability. In addition, Failure Modes and Effects Analyses (FMEA), Preliminary Hazard Analyses (PHA), and Fault Tree Analysis (FTA) were performed to allow detailed evaluation of the IME concept. A discussion of these system reliability concepts is also presented.

  20. Reliability studies of Integrated Modular Engine system designs

    NASA Technical Reports Server (NTRS)

    Hardy, Terry L.; Rapp, Douglas C.

    1993-01-01

    A study was performed to evaluate the reliability of Integrated Modular Engine (IME) concepts. Comparisons were made between networked IME systems and non-networked discrete systems using expander cycle configurations. Both redundant and non-redundant systems were analyzed. Binomial approximation and Markov analysis techniques were employed to evaluate total system reliability. In addition, Failure Modes and Effects Analyses (FMEA), Preliminary Hazard Analyses (PHA), and Fault Tree Analysis (FTA) were performed to allow detailed evaluation of the IME concept. A discussion of these system reliability concepts is also presented.

  1. Reliability studies of integrated modular engine system designs

    NASA Astrophysics Data System (ADS)

    Hardy, Terry L.; Rapp, Douglas C.

    1993-06-01

    A study was performed to evaluate the reliability of Integrated Modular Engine (IME) concepts. Comparisons were made between networked IME systems and non-networked discrete systems using expander cycle configurations. Both redundant and non-redundant systems were analyzed. Binomial approximation and Markov analysis techniques were employed to evaluate total system reliability. In addition, Failure Modes and Effects Analyses (FMEA), Preliminary Hazard Analyses (PHA), and Fault Tree Analysis (FTA) were performed to allow detailed evaluation of the IME concept. A discussion of these system reliability concepts is also presented.

  2. Reliability studies of Integrated Modular Engine system designs

    NASA Astrophysics Data System (ADS)

    Hardy, Terry L.; Rapp, Douglas C.

    1993-06-01

    A study was performed to evaluate the reliability of Integrated Modular Engine (IME) concepts. Comparisons were made between networked IME systems and non-networked discrete systems using expander cycle configurations. Both redundant and non-redundant systems were analyzed. Binomial approximation and Markov analysis techniques were employed to evaluate total system reliability. In addition, Failure Modes and Effects Analyses (FMEA), Preliminary Hazard Analyses (PHA), and Fault Tree Analysis (FTA) were performed to allow detailed evaluation of the IME concept. A discussion of these system reliability concepts is also presented.

  3. Comparison of growth, serum biochemistries and n-6 fatty acid metabolism in rats fed diets supplemented with high-gamma-linolenic acid safflower oil or borage oil for 90 days.

    PubMed

    Tso, Patrick; Caldwell, Jody; Lee, Dana; Boivin, Gregory P; DeMichele, Stephen J

    2012-06-01

    Recently, steps have been taken to further developments toward increasing gamma-linolenic acid (GLA) concentration and lowering costs in plant seed oils using transgenic technology. Through identification and expression of a fungal delta-6 desaturase gene in the high linoleic acid safflower plant, the seeds from this genetic transformation produce oil with >40% GLA (high GLA safflower oil (HGSO)). The aim of the study was to compare the effects of feeding HGSO to a generally recognized as safe source of GLA, borage oil, in a 90 day safety study in rats. Weanling male and female Sprague-Dawley rats were fed a semi-synthetic, fat free, pelleted diet (AIN93G) supplemented with a 10% (wt/wt) oil blend containing HGSO or borage oil, with equivalent GLA levels. Results demonstrated that feeding diets containing HGSO or borage oil for 90 days had similar biologic effects with regard to growth characteristics, body composition, behavior, organ weight and histology, and parameters of hematology and serum biochemistries in both sexes. Metabolism of the primary n-6 fatty acids in plasma and organ phospholipids was similar, despite minor changes in females. We conclude that HGSO is biologically equivalent to borage oil and provides a safe alternative source of GLA in the diet.

  4. Test of Creative Imagination: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Gundogan, Aysun; Ari, Meziyet; Gonen, Mubeccel

    2013-01-01

    The purpose of this study was to investigate validity and reliability of the test of creative imagination. This study was conducted with the participation of 1000 children, aged between 9-14 and were studying in six primary schools in the city center of Denizli Province, chosen by cluster ratio sampling. In the study, it was revealed that the…

  5. Human Rights Attitude Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Ercan, Recep; Yaman, Tugba; Demir, Selcuk Besir

    2015-01-01

    The objective of this study is to develop a valid and reliable attitude scale having quality psychometric features that can measure secondary school students' attitudes towards human rights. The study group of the research is comprised by 710 6th, 7th and 8th grade students who study at 4 secondary schools in the centre of Sivas. The study group…

  6. Emphatic Tendency Scale for Student Teachers: Validity and Reliability Studies

    ERIC Educational Resources Information Center

    Kocak, Canan; Onen, Aysem Seda

    2013-01-01

    The purpose of this study was to analyze the validity and reliability of the Empathic Tendency Scale, which was developed in order to identify student teachers' empathic tendencies. The sampling of the study consisted of 730 student teachers studying at Hacettepe University Faculty of Education. To determine the factor pattern of Empathic Tendency…

  7. A functional variant in the 3ˈ-UTR of VEGF predicts the 90-day outcome of ischemic stroke in Chinese patients

    PubMed Central

    Jin, Lei; Weng, Yingfeng; Wang, Yujie; Wu, Hui; Li, Xia; Huang, Ying; Wang, Shengyue

    2017-01-01

    Vascular endothelial growth factor (VEGF) plays critical roles in angiogenesis and vasculogenesis, which are associated with post-stroke functional recovery. However, the effects of the VEGFA polymorphisms on the outcome of ischemic stroke (IS) have been rarely reported. We therefore investigated the associations of +936C/T variant (rs3025039) with the susceptibilities and the 90-day outcomes from 494 IS patients and 337 healthy controls in Chinese population through the establishment of logistic multivariate regression model. Stroke severity at admission and outcome of 90 days were respectively assessed according to the National Institutes of Health Stroke Scale and the modified Rankin Scale. The analysis showed that there were no significant associations of the rs3025039 genotypes with the susceptibility (P = 0.229) and the severity (P = 0.734). However, when we divided the 308 IS patients into two groups according to the different outcomes, we found that the rs3025039 TC+TT genotype significantly increased the risk of poor recovery [adjusted odds ratio (OR), 1.99; 95% confidence interval (CI), 1.18–3.37]. Interestingly, we observed another 3ˈUTR variant, +1451C/T (rs3025040), exhibited strong linkage disequilibrium (r2 = 1.0) with +936C/T and was located in a predicted microRNA-binding site. The rs3025040 T allele significantly decreased the luciferase activities in four cell lines, which indicated a potential disruption of the miRNA-mRNA interaction that would result in lower VEGF expression levels. Our data suggested that the +936C/T variants significantly increased the risk of poorer stroke outcome by affecting the bindings of miR-199a and miR-199b to VEGF mRNA at the rs30250340 polymorphic site. PMID:28234972

  8. Reflective Thinking Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Basol, Gulsah; Evin Gencel, Ilke

    2013-01-01

    The purpose of this study was to adapt Reflective Thinking Scale to Turkish and investigate its validity and reliability over a Turkish university students' sample. Reflective Thinking Scale (RTS) is a 5 point Likert scale (ranging from 1 corresponding Agree Completely, 3 to Neutral, and 5 to Not Agree Completely), purposed to measure reflective…

  9. Thermal Reliability Study of Bypass Diodes in Photovoltaic Modules (Poster)

    SciTech Connect

    Zhang, Z.; Wohlgemuth, J.; Kurtz, S.

    2013-05-01

    This paper presents the result of high-temperature durability and thermal cycling testing and analysis for the selected diodes to study the detail of the thermal design and relative long-term reliability of the bypass diodes used to limit the detrimental effects of module hot-spot susceptibility.

  10. Monte Carlo Approach for Reliability Estimations in Generalizability Studies.

    ERIC Educational Resources Information Center

    Dimitrov, Dimiter M.

    A Monte Carlo approach is proposed, using the Statistical Analysis System (SAS) programming language, for estimating reliability coefficients in generalizability theory studies. Test scores are generated by a probabilistic model that considers the probability for a person with a given ability score to answer an item with a given difficulty…

  11. Genome-wide gene expression effects in B6C3F1 mouse intestinal epithelia following 7 and 90 days of exposure to hexavalent chromium in drinking water

    SciTech Connect

    Kopec, Anna K.; Kim, Suntae; Forgacs, Agnes L.; Zacharewski, Timothy R.; Proctor, Deborah M.; Harris, Mark A.; Haws, Laurie C.; Thompson, Chad M.

    2012-02-15

    Chronic administration of high doses of hexavalent chromium [Cr(VI)] as sodium dichromate dihydrate (SDD) elicits alimentary cancers in mice. To further elucidate key events underlying tumor formation, a 90-day drinking water study was conducted in B6C3F1 mice. Differential gene expression was examined in duodenal and jejunal epithelial samples following 7 or 90 days of exposure to 0, 0.3, 4, 14, 60, 170 or 520 mg/L SDD in drinking water. Genome-wide microarray analyses identified 6562 duodenal and 4448 jejunal unique differentially expressed genes at day 8, and 4630 and 4845 unique changes, respectively, in the duodenum and jejunum at day 91. Comparative analysis identified significant overlap in duodenal and jejunal differential gene expression. Automated dose–response modeling identified > 80% of the differentially expressed genes exhibited sigmoidal dose–response curves with EC{sub 50} values ranging from 10 to 100 mg/L SDD. Only 16 genes satisfying the dose-dependent differential expression criteria had EC{sub 50} values < 10 mg/L SDD, 3 of which were regulated by Nrf2, suggesting oxidative stress in response to SDD at low concentrations. Analyses of differentially expressed genes identified over-represented functions associated with oxidative stress, cell cycle, lipid metabolism, and immune responses consistent with the reported effects on redox status and histopathology at corresponding SDD drinking water concentrations. Collectively, these data are consistent with a mode of action involving oxidative stress and cytotoxicity as early key events. This suggests that the tumorigenic effects of chronic Cr(VI) oral exposure likely require chronic tissue damage and compensatory epithelial cell proliferation. Highlights: ► Mouse small intestine gene expression is highly responsive to hexavalent chromium [Cr(VI)]. ► Cr(VI) elicits more differential gene expression after 7 days of exposure than 90 days of exposure. ► Oral exposure to Cr(VI) leads to

  12. Myers-Briggs Type Indicator Score Reliability across Studies: A Meta-Analytic Reliability.

    ERIC Educational Resources Information Center

    Capraro, Robert M.; Capraro, Mary Margaret

    2002-01-01

    Submitted the Myers-Briggs Type Indicator (MBTI) to a descriptive reliability generalization analysis to characterize the variability of measurement error in MBTI scores across administrations. In general the MBTI and its scales yielded scores with strong internal consistency and test-retest reliability estimates. (SLD)

  13. Genome-wide gene expression effects in B6C3F1 mouse intestinal epithelia following 7 and 90days of exposure to hexavalent chromium in drinking water.

    PubMed

    Kopec, Anna K; Kim, Suntae; Forgacs, Agnes L; Zacharewski, Timothy R; Proctor, Deborah M; Harris, Mark A; Haws, Laurie C; Thompson, Chad M

    2012-02-15

    Chronic administration of high doses of hexavalent chromium [Cr(VI)] as sodium dichromate dihydrate (SDD) elicits alimentary cancers in mice. To further elucidate key events underlying tumor formation, a 90-day drinking water study was conducted in B6C3F1 mice. Differential gene expression was examined in duodenal and jejunal epithelial samples following 7 or 90days of exposure to 0, 0.3, 4, 14, 60, 170 or 520mg/L SDD in drinking water. Genome-wide microarray analyses identified 6562 duodenal and 4448 jejunal unique differentially expressed genes at day 8, and 4630 and 4845 unique changes, respectively, in the duodenum and jejunum at day 91. Comparative analysis identified significant overlap in duodenal and jejunal differential gene expression. Automated dose-response modeling identified >80% of the differentially expressed genes exhibited sigmoidal dose-response curves with EC(50) values ranging from 10 to 100mg/L SDD. Only 16 genes satisfying the dose-dependent differential expression criteria had EC(50) values <10mg/L SDD, 3 of which were regulated by Nrf2, suggesting oxidative stress in response to SDD at low concentrations. Analyses of differentially expressed genes identified over-represented functions associated with oxidative stress, cell cycle, lipid metabolism, and immune responses consistent with the reported effects on redox status and histopathology at corresponding SDD drinking water concentrations. Collectively, these data are consistent with a mode of action involving oxidative stress and cytotoxicity as early key events. This suggests that the tumorigenic effects of chronic Cr(VI) oral exposure likely require chronic tissue damage and compensatory epithelial cell proliferation.

  14. Impact of Device Scaling on Deep Sub-micron Transistor Reliability: A Study of Reliability Trends using SRAM

    NASA Technical Reports Server (NTRS)

    White, Mark; Huang, Bing; Qin, Jin; Gur, Zvi; Talmor, Michael; Chen, Yuan; Heidecker, Jason; Nguyen, Duc; Bernstein, Joseph

    2005-01-01

    As microelectronics are scaled in to the deep sub-micron regime, users of advanced technology CMOS, particularly in high-reliability applications, should reassess how scaling effects impact long-term reliability. An experimental based reliability study of industrial grade SRAMs, consisting of three different technology nodes, is proposed to substantiate current acceleration models for temperature and voltage life-stress relationships. This reliability study utilizes step-stress techniques to evaluate memory technologies (0.25mum, 0.15mum, and 0.13mum) embedded in many of today's high-reliability space/aerospace applications. Two acceleration modeling approaches are presented to relate experimental FIT calculations to Mfr's qualification data.

  15. [Interrater studies of evaluating the reliability of somatic findings].

    PubMed

    Saur, P M; Pfingsten, M; Ensink, F B; Heinemann, R; Koch, D; Seeger, D; Hildebrandt, J

    1996-08-01

    20 patients (11 female, 9 male) without low back pain were included in two interrater studies carried out by three physical therapists. The following variables were investigated: shape of the spine, iliac crest heights, twisting of the pelvis, spine test, length of legs, Patrick sign, Schober test, fingertip-to-floor measurements, flexion and extension of the lumbar spine, straight-leg raising, and length of the iliopsoas and the rectus muscles. Intraclass coefficients for the ordinal variables, and kappa coefficients for the nominal variables were calculated for evaluation of interrater agreement. In both investigations, the Schober sign, lumbar flexion, fingertip-to-floor measurements, straight-leg raising of the left leg, and lengths of both legs were almost perfectly reliable. All other variables exhibited a lower reliability between the three therapists.

  16. Reliability and availability studies in the RIA driver linac.

    SciTech Connect

    Lessner, E. S.; Ostroumov, P. N.; Physics

    2005-01-01

    The Rare Isotope Accelerator (RIA) facility will include various complex systems and must provide radioactive beams to many users simultaneously. The availability of radioactive beams for most experiments at the fully-commissioned facility should be as high as possible within design cost limitations. To make a realistic estimate of the achievable reliability a detailed analysis is required. The RIA driver linac is a complex machine containing a large number of superconducting (SC) resonators and capable of accelerating multiple-charge-state beams [1]. At the pre-CDR stage of the design it is essential to identify critical facility subsystem failures that can prevent the driver linac from operating. The reliability and availability of the driver linac were studied using expert information and data from operating machines such as ATLAS, APS, JLab, and LANL. Availability studies are performed with a Monte-Carlo simulation code previously applied to availability assessments of the NLC facility [2] and the results used to identify subsystem failures that most affect the availability and reliability of the RIA driver, and guide design iterations and component specifications to address identified problems.

  17. Study on the Reliability Data Analysis Method for Electric Fuze

    NASA Astrophysics Data System (ADS)

    Xu, Jianjun; Wang, Zhijun

    Some key points of reliable data collection and analytic technology of the electric fuze are discussed in this paper. The produce, collection methods, note proceedings of the reliable data of the electric fuze are also discussed, so reliable database of every component in the electric fuzes should be established, the primary and secondary method - - an analytical method which uses the reliable data of the electric fuze with the application of the fuze products, then the key components which have influences on the reliability can be found.

  18. Classical Perturbation Theory for Monte Carlo Studies of System Reliability

    SciTech Connect

    Lewins, Jeffrey D.

    2001-03-15

    A variational principle for a Markov system allows the derivation of perturbation theory for models of system reliability, with prospects of extension to generalized Markov processes of a wide nature. It is envisaged that Monte Carlo or stochastic simulation will supply the trial functions for such a treatment, which obviates the standard difficulties of direct analog Monte Carlo perturbation studies. The development is given in the specific mode for first- and second-order theory, using an example with known analytical solutions. The adjoint equation is identified with the importance function and a discussion given as to how both the forward and backward (adjoint) fields can be obtained from a single Monte Carlo study, with similar interpretations for the additional functions required by second-order theory. Generalized Markov models with age-dependence are identified as coming into the scope of this perturbation theory.

  19. Doses for post-Chernobyl epidemiological studies: are they reliable?

    PubMed

    Drozdovitch, Vladimir; Chumak, Vadim; Kesminiene, Ausrele; Ostroumova, Evgenia; Bouville, André

    2016-09-01

    On 26 April 2016, thirty years will have elapsed since the occurrence of the Chernobyl accident, which has so far been the most severe in the history of the nuclear reactor industry. Numerous epidemiological studies were conducted to evaluate the possible health consequences of the accident. Since the credibility of the association between the radiation exposure and health outcome is highly dependent on the adequacy of the dosimetric quantities used in these studies, this paper makes an effort to overview the methods used to estimate individual doses and the associated uncertainties in the main analytical epidemiological studies (i.e. cohort or case-control) related to the Chernobyl accident. Based on the thorough analysis and comparison with other radiation studies, the authors conclude that individual doses for the Chernobyl analytical epidemiological studies have been calculated with a relatively high degree of reliability and well-characterized uncertainties, and that they compare favorably with many other non-Chernobyl studies. The major strengths of the Chernobyl studies are: (1) they are grounded on a large number of measurements, either performed on humans or made in the environment; and (2) extensive effort has been invested to evaluate the uncertainties associated with the dose estimates. Nevertheless, gaps in the methodology are identified and suggestions for the possible improvement of the current dose estimates are made.

  20. Contaminants in landfill soils - Reliability of prefeasibility studies.

    PubMed

    Hölzle, Ingo

    2016-08-31

    Recent landfill mining studies have researched the potential for resource recovery using samples from core drilling or grab cranes. However, most studies used small sample numbers, which may not represent the heterogeneous landfill composition. As a consequence, there exists a high risk of an incorrect economic and/or ecological evaluation. The main objective of this work is to investigate the possibilities and limitations of preliminary investigations concerning the crucial soil composition. The preliminary samples of landfill investigations were compared to the excavation samples from three completely excavated landfills in Germany. In addition, the research compared the reliability of prediction of the two investigation methods, core drilling and grab crane. Sampling using a grab crane led to better results, even for smaller investigations of 10 samples. Analyses of both methods showed sufficiently accurate results to make predictions (standard error 5%, level of confidence 95%) for most heavy metals, cyanide and PAH in the dry substance and for sulphate, barium, Benzo[a]pyrene, pH and the electrical conductivity in leachate analyses of soil type waste. While chrome and nickel showed less accurate results, the concentrations of hydrocarbons, TOC, DOC, PCB and fluorine (leachate) were not predictable even for sample numbers of up to 59. Overestimations of pollutant concentrations were more frequently apparent in drilling, and underestimations when using a grab crane. The dispersion of the element and elemental composition had no direct impact on the reliability of prediction. Thus, an individual consideration of the particular element or elemental composition for dry substance and leachate analyses is recommended to adapt the sample strategy and calculate an optimum sample number.

  1. 90-Day Inhalation Toxicity Study of Hydroprocessed Esters and Fatty Acids (HEFA) Bio-Based Jet Fuel in Rats (Rattus norvegicus) with Neurotoxicity Testing and Genotoxicity Assay

    DTIC Science & Technology

    2013-06-01

    nociception , social interaction, the forced swim test, spontaneous locomotor activity, passive avoidance or Morris water maze performance. However...system. V.4. Technical Methods V.4.1. Pain / Distress Assessment V.4.1.1. APHIS Form 7023 Information V.4.1.1.1. Number of Animals V...4.1.1.1.1. Column C: 0 V.4.1.1.1.2. Column D: 150 V.4.1.1.1.3. Column E: 0 V.4.1.2. Pain Relief / Prevention V.4.1.2.1. Anesthesia

  2. Studies on the Inhalation Toxicity of Dyes Present in Colored Smoke Munitions. Phase IV. 90-Day Inhalation Exposures of Rats to Dye Aerosols

    DTIC Science & Technology

    1985-10-01

    epithelial cell hyperplasla and proliferation of foamy alveolar •. macrophages and lymphoid hyperplasia in the tracheobronchial lymph nodes of rats exposed...These accumulations of alveolar macrophages were accompanied by slight to moderate hyperplasia of k Type II cells (granular pneumocytes). In the nasal...dose rats. These accumulations of alveolar macrophages were accompanied by slight to moderate hyperplasii of Type II cells (granular pneumocytes). In the

  3. 90-Day Inhalation Toxicity Study of Bio-Derived Gevo Alcohol-to-Jet (ATJ) Synthetic Paraffinic Kerosene (SPK) in Rats with Neurotoxicity Testing and Genotoxicity Assay

    DTIC Science & Technology

    2015-05-31

    Animals were fed a certified rodent diet (Formulab Diet Purina Lab Chow, PMI Nutrition, International, LLC, Brentwood MO), ad libitum, except during...weights of the liver , kidneys, adrenals, testes, epididymides, ovaries, uterus, thymus, spleen, brain, and heart were obtained after dissection from the...g) 0.02 0.01 0.02 0.02 % BW (mean) 0.02 0.02 0.02 0.02 % BW (SD) 0.01 0.005 0.005 0.01 Liver Average (g) 10.15a 10.51 9.98 10.89 SD (g) 0.46a

  4. 90-Day Inhalation Toxicity Study of Swedish Biofuel Alcohol-to-Jet (ATJ) Synthetic Kerosene with Aromatics (SPA) in Rats with Neurotoxicity Testing and Genotoxicity Assay

    DTIC Science & Technology

    2015-09-01

    concentration in the 700 or 2000 mg/m3 exposure groups. No indications of changes in reproductive health were found when vaginal cytology and sperm...deemed biologically significant. As an indicator of reproductive health, vaginal cytology was assessed during week 9 of exposure and sperm count...endpoints assessed were neurotoxicity, reproductive toxicity, and genotoxicity. 4 Distribution Statement A. Approved for public release

  5. Fatigue case study and reliability analyses for wind turbines

    SciTech Connect

    Sutherland, H.J.; Veers, P.S.

    1994-12-31

    Modern wind turbines are fatigue critical machines used to produce electrical power. To insure long term, reliable operation, their structure must be optimized if they are to be economically viable. The fatigue and reliability projects in Sandia`s Wind Energy Program are developing the analysis tools required to accomplish these design requirements. The first section of the paper formulates the fatigue analysis of a wind turbine using a cumulative damage technique. The second section uses reliability analysis for quantifying the uncertainties and the inherent randomness associated with turbine performance and the prediction of service lifetimes. Both research areas are highlighted with typical results.

  6. Reliability study of an emerging fire suppression system

    DOE PAGES

    Miller, David A.; Rossati, Lyric M.; Fritz, Nathan K.; ...

    2015-11-01

    Self-contained fire extinguishers are a robust, reliable and minimally invasive means of fire suppression for gloveboxes. Plutonium gloveboxes are known to present harsh environmental conditions for polymer materials, these include radiation damage and chemical exposure, both of which tend to degrade the lifetime of engineered polymer components. The primary component of interest in self-contained fire extinguishers is the nylon 6-6 machined tube that comprises the main body of the system.Thermo-mechanical modeling and characterization of nylon 6-6 for use in plutonium glovebox applications has been carried out. Data has been generated regarding property degradation leading to poor, or reduced, engineering performancemore » of nylon 6-6 components. In this study, nylon 6-6 tensile specimens conforming to the casing of self-contained fire extinguisher systems have been exposed to hydrochloric, nitric, and sulfuric acids. This information was used to predict the performance of a load bearing engineering component comprised of nylon 6-6 and designed to operate in a consistent manner over a specified time period. The study provides a fundamental understanding of the engineering performance of the fire suppression system and the effects of environmental degradation due to acid exposure on engineering performance. Data generated help identify the limitations of self-contained fire extinguishers. No critical areas of concern for plutonium glovebox applications of nylon 6-6 have been identified when considering exposure to mineral acid.« less

  7. Reliable in vitro studies require appropriate ovarian cancer cell lines

    PubMed Central

    2014-01-01

    Ovarian cancer is the fifth most common cause of cancer death in women and the leading cause of death from gynaecological malignancies. Of the 75% women diagnosed with locally advanced or disseminated disease, only 30% will survive five years following treatment. This poor prognosis is due to the following reasons: limited understanding of the tumor origin, unclear initiating events and early developmental stages of ovarian cancer, lack of reliable ovarian cancer-specific biomarkers, and drug resistance in advanced cases. In the past, in vitro studies using cell line models have been an invaluable tool for basic, discovery-driven cancer research. However, numerous issues including misidentification and cross-contamination of cell lines have hindered research efforts. In this study we examined all ovarian cancer cell lines available from cell banks. Hereby, we identified inconsistencies in the reporting, difficulties in the identification of cell origin or clinical data of the donor patients, restricted ethnic and histological type representation, and a lack of tubal and peritoneal cancer cell lines. We recommend that all cell lines should be distributed via official cell banks only with strict guidelines regarding the minimal available information required to improve the quality of ovarian cancer research in future. PMID:24936210

  8. Reliability study of an emerging fire suppression system

    SciTech Connect

    Miller, David A.; Rossati, Lyric M.; Fritz, Nathan K.; Cournoyer, Michael E.; Granzow, Howard N.

    2015-11-01

    Self-contained fire extinguishers are a robust, reliable and minimally invasive means of fire suppression for gloveboxes. Plutonium gloveboxes are known to present harsh environmental conditions for polymer materials, these include radiation damage and chemical exposure, both of which tend to degrade the lifetime of engineered polymer components. The primary component of interest in self-contained fire extinguishers is the nylon 6-6 machined tube that comprises the main body of the system.Thermo-mechanical modeling and characterization of nylon 6-6 for use in plutonium glovebox applications has been carried out. Data has been generated regarding property degradation leading to poor, or reduced, engineering performance of nylon 6-6 components. In this study, nylon 6-6 tensile specimens conforming to the casing of self-contained fire extinguisher systems have been exposed to hydrochloric, nitric, and sulfuric acids. This information was used to predict the performance of a load bearing engineering component comprised of nylon 6-6 and designed to operate in a consistent manner over a specified time period. The study provides a fundamental understanding of the engineering performance of the fire suppression system and the effects of environmental degradation due to acid exposure on engineering performance. Data generated help identify the limitations of self-contained fire extinguishers. No critical areas of concern for plutonium glovebox applications of nylon 6-6 have been identified when considering exposure to mineral acid.

  9. Remotely Operated Vehicle ROV/AUV Reliability Study. Phase 2.

    DTIC Science & Technology

    1989-09-01

    Cable Connectors for Deep Ocean Applications . Port Hueneme, CA: Civil Engineering Lab., Naval Construction Battalion Center, Technical Report R806...competition. As a result, commercial- grade vehicles with broad applications are modified for specific requirements. These vehicles have reliability and other...Navy’s use of commercial grade broad application vehicles that have been modified for specific requirements. Long term reliability is not a design

  10. Environmental education curriculum evaluation questionnaire: A reliability and validity study

    NASA Astrophysics Data System (ADS)

    Minner, Daphne Diane

    The intention of this research project was to bridge the gap between social science research and application to the environmental domain through the development of a theoretically derived instrument designed to give educators a template by which to evaluate environmental education curricula. The theoretical base for instrument development was provided by several developmental theories such as Piaget's theory of cognitive development, Developmental Systems Theory, Life-span Perspective, as well as curriculum research within the area of environmental education. This theoretical base fueled the generation of a list of components which were then translated into a questionnaire with specific questions relevant to the environmental education domain. The specific research question for this project is: Can a valid assessment instrument based largely on human development and education theory be developed that reliably discriminates high, moderate, and low quality in environmental education curricula? The types of analyses conducted to answer this question were interrater reliability (percent agreement, Cohen's Kappa coefficient, Pearson's Product-Moment correlation coefficient), test-retest reliability (percent agreement, correlation), and criterion-related validity (correlation). Face validity and content validity were also assessed through thorough reviews. Overall results indicate that 29% of the questions on the questionnaire demonstrated a high level of interrater reliability and 43% of the questions demonstrated a moderate level of interrater reliability. Seventy-one percent of the questions demonstrated a high test-retest reliability and 5% a moderate level. Fifty-five percent of the questions on the questionnaire were reliable (high or moderate) both across time and raters. Only eight questions (8%) did not show either interrater or test-retest reliability. The global overall rating of high, medium, or low quality was reliable across both coders and time, indicating

  11. The investigation of supply chain's reliability measure: a case study

    NASA Astrophysics Data System (ADS)

    Taghizadeh, Houshang; Hafezi, Ehsan

    2012-10-01

    In this paper, using supply chain operational reference, the reliability evaluation of available relationships in supply chain is investigated. For this purpose, in the first step, the chain under investigation is divided into several stages including first and second suppliers, initial and final customers, and the producing company. Based on the formed relationships between these stages, the supply chain system is then broken down into different subsystem parts. The formed relationships between the stages are based on the transportation of the orders between stages. Paying attention to the system elements' location, which can be in one of the five forms of series namely parallel, series/parallel, parallel/series, or their combinations, we determine the structure of relationships in the divided subsystems. According to reliability evaluation scales on the three levels of supply chain, the reliability of each chain is then calculated. Finally, using the formulas of calculating the reliability in combined systems, the reliability of each system and ultimately the whole system is investigated.

  12. Preliminary study of the reliability of imaging charge coupled devices

    NASA Technical Reports Server (NTRS)

    Beall, J. R.; Borenstein, M. D.; Homan, R. A.; Johnson, D. L.; Wilson, D. D.; Young, V. F.

    1978-01-01

    Imaging CCDs are capable of low light level response and high signal-to-noise ratios. In space applications they offer the user the ability to achieve extremely high resolution imaging with minimum circuitry in the photo sensor array. This work relates the CCD121H Fairchild device to the fundamentals of CCDs and the representative technologies. Several failure modes are described, construction is analyzed and test results are reported. In addition, the relationship of the device reliability to packaging principles is analyzed and test data presented. Finally, a test program is defined for more general reliability evaluation of CCDs.

  13. Reliability studies of diagnostic methods in Indian traditional Ayurveda medicine: An overview

    PubMed Central

    Kurande, Vrinda Hitendra; Waagepetersen, Rasmus; Toft, Egon; Prasad, Ramjee

    2013-01-01

    Recently, a need to develop supportive new scientific evidence for contemporary Ayurveda has emerged. One of the research objectives is an assessment of the reliability of diagnoses and treatment. Reliability is a quantitative measure of consistency. It is a crucial issue in classification (such as prakriti classification), method development (pulse diagnosis), quality assurance for diagnosis and treatment and in the conduct of clinical studies. Several reliability studies are conducted in western medicine. The investigation of the reliability of traditional Chinese, Japanese and Sasang medicine diagnoses is in the formative stage. However, reliability studies in Ayurveda are in the preliminary stage. In this paper, examples are provided to illustrate relevant concepts of reliability studies of diagnostic methods and their implication in practice, education, and training. An introduction to reliability estimates and different study designs and statistical analysis is given for future studies in Ayurveda. PMID:23930037

  14. The Impact Analysis of Psychological Reliability of Population Pilot Study for Selection of Particular Reliable Multi-Choice Item Test in Foreign Language Research Work

    ERIC Educational Resources Information Center

    Fazeli, Seyed Hossein

    2010-01-01

    The purpose of research described in the current study is the psychological reliability, its importance, application, and more to investigate on the impact analysis of psychological reliability of population pilot study for selection of particular reliable multi-choice item test in foreign language research work. The population for subject…

  15. Long life high reliability thermal control systems study data handbook

    NASA Technical Reports Server (NTRS)

    Scollon, T. R., Jr.; Carpitella, M. J.

    1971-01-01

    The development of thermal control systems with high reliability and long service life is discussed. Various passive and semi-active thermal control systems which have been installed on space vehicles are described. The properties of the various coatings are presented in tabular form.

  16. Reliability and availability analysis for robot subsystem in automotive assembly plant: a case study

    NASA Astrophysics Data System (ADS)

    Fudzin, A. F.; Majid, M. A. A.

    2015-12-01

    The automotive assembly plant in a manufacturing environment consists of conveying systems and robots. Robots with high reliability will ensure no interruption during production. This study is to analyze the individual robot reliability compared to reliability of robots subsystem in series configuration. Availability was computed based on individual robots breakdown data. Failures due to robots breakdown often occurred during the operations. Actual maintenance data for a period of seven years were used for the analysis. Incorporation of failures rate and mean time between failures yield the reliability computation with the assumption of constant failure rate. Result from the analysis based on 5000 operating hours indicated reliability of series configuration of robots in a subsystem decreased to 2.8% in comparison to 38% reliability of the individual robot with the lowest reliability. The calculated lowest availability of the robots is 99.41%. The robot with the lowest reliability and availability should be considered for replacement.

  17. Studies relevant to the design of reliable automotive electronics

    NASA Astrophysics Data System (ADS)

    Zeng, Hua

    This dissertation describes three independent studies related to the design of reliable automotive electronics. The topics covered are: the estimation of the radiated emissions from power bus structures, EM propagation of tire pressure monitoring systems (TPMS), and examinations of corrosion-induced faults in a connector. The first chapter describes a method for estimating the maximum possible radiated emissions from a printed circuit board power bus. An analysis based on a lossy cavity model is performed to determine the maximum possible radiated field corresponding to a given power bus noise voltage. A closed-form expression relating the maximum power bus noise voltage to the radiation peaks is then derived. This expression is solved in reverse to determine the minimum power bus voltage necessary to generate a radiated field and can be applied to measured values of power bus noise voltage to determine whether radiation directly from the power bus is potentially the emissions source. The second chapter identifies transmission parameters from a rotating tire and the vehicle body's effect on tire sensor transmission and propagation; relates these effects to receiver antenna packaging requirements; and then, based on these results, proposes the antenna design of employing car body as a part. In the new proposed TPMS design, a 20mm x 5mm loop antenna with a 40mm x 10mm slot beneath it is added to capture the surface currents of the car body and block the current path to increase the current density around the loop antenna. The simulation results show that this design exhibits a propagation factor 150 times larger than the traditional design. The third chapter investigates the effects of different contaminants (salt, oil, grease) on the shunt resistance between pins of a cable connector. The test results show that salt-induced corrosion and moisture may cause intermittent shunting resistances capable of affecting the normal operation of automotive systems. One

  18. Reliability study of refractory gate gallium arsenide MESFETS

    NASA Technical Reports Server (NTRS)

    Yin, J. C. W.; Portnoy, W. M.

    1981-01-01

    Refractory gate MESFET's were fabricated as an alternative to aluminum gate devices, which have been found to be unreliable as RF power amplifiers. In order to determine the reliability of the new structures, statistics of failure and information about mechanisms of failure in refractory gate MESFET's are given. Test transistors were stressed under conditions of high temperature and forward gate current to enhance failure. Results of work at 150 C and 275 C are reported.

  19. Reliability studies of incident coding systems in high hazard industries: A narrative review of study methodology.

    PubMed

    Olsen, Nikki S

    2013-03-01

    This paper reviews the current literature on incident coding system reliability and discusses the methods applied in the conduct and measurement of reliability. The search strategy targeted three electronic databases using a list of search terms and the results were examined for relevance, including any additional relevant articles from the bibliographies. Twenty five papers met the relevance criteria and their methods are discussed. Disagreements in the selection of methods between reliability researchers are highlighted as are the effects of method selection on the outcome of the trials. The review provides evidence that the meaningfulness of and confidence in results is directly affected by the methodologies employed by the researcher during the preparation, conduct and analysis of the reliability study. Furthermore, the review highlights the heterogeneity of methodologies employed by researchers measuring reliability of incident coding techniques, reducing the ability to critically compare and appraise techniques being considered for the adoption of report coding and trend analysis by client organisations. It is recommended that future research focuses on the standardisation of reliability research and measurement within the incident coding domain.

  20. Study of vertical breakwater reliability based on copulas

    NASA Astrophysics Data System (ADS)

    Dong, Sheng; Li, Jingjing; Li, Xue; Wei, Yong

    2016-04-01

    The reliability of a vertical breakwater is calculated using direct integration methods based on joint density functions. The horizontal and uplifting wave forces on the vertical breakwater can be well fitted by the lognormal and the Gumbel distributions, respectively. The joint distribution of the horizontal and uplifting wave forces is analyzed using different probabilistic distributions, including the bivariate logistic Gumbel distribution, the bivariate lognormal distribution, and three bivariate Archimedean copulas functions constructed with different marginal distributions simultaneously. We use the fully nested copulas to construct multivariate distributions taking into account related variables. Different goodness fitting tests are carried out to determine the best bivariate copula model for wave forces on a vertical breakwater. We show that a bivariate model constructed by Frank copula gives the best reliability analysis, using marginal distributions of Gumbel and lognormal to account for uplifting pressure and horizontal wave force on a vertical breakwater, respectively. The results show that failure probability of the vertical breakwater calculated by multivariate density function is comparable to those by the Joint Committee on Structural Safety methods. As copulas are suitable for constructing a bivariate or multivariate joint distribution, they have great potential in reliability analysis for other coastal structures.

  1. The REPAS Study: Reliability Evaluation of Passive Safety Systems

    SciTech Connect

    Ricotti, M.E.; Bianchi, F.; Burgazzi, L.; D'Auria, F.; Galassi, G.

    2002-07-01

    The strategy of approach to the problem moves from the consideration that a passive system should be theoretically more reliable than an active one. In fact it does not need any external input or energy to operate and it relies only upon natural physical laws (e.g. gravity, natural circulation, internally stored energy, etc.) and/or 'intelligent' use of the energy inherently available in the system (e.g. chemical reaction, decay heat, etc.). Nevertheless the passive system may fail its mission not only as a consequence of classical mechanical failure of components, but also for deviation from the expected behaviour, due to physical phenomena mainly related to thermal-hydraulics or due to different boundary and initial conditions. The main sources of physical failure are identified and a probability of occurrence is assigned. The reliability analysis is performed on a passive system which operates in two-phase, natural circulation. The selected system is a loop including a heat source and a heat sink where the condensation occurs. The system behavior under different configurations has been simulated via best-estimate code (Relap5 mod3.2). The results are shown and can be treated in such a way to give qualitative and quantitative information on the system reliability. Main routes of development of the methodology are also depicted. (authors)

  2. Nuclear electric propulsion operational reliability and crew safety study: NEP systems/modeling report

    NASA Technical Reports Server (NTRS)

    Karns, James

    1993-01-01

    The objective of this study was to establish the initial quantitative reliability bounds for nuclear electric propulsion systems in a manned Mars mission required to ensure crew safety and mission success. Finding the reliability bounds involves balancing top-down (mission driven) requirements and bottom-up (technology driven) capabilities. In seeking this balance we hope to accomplish the following: (1) provide design insights into the achievability of the baseline design in terms of reliability requirements, given the existing technology base; (2) suggest alternative design approaches which might enhance reliability and crew safety; and (3) indicate what technology areas require significant research and development to achieve the reliability objectives.

  3. The "RG Sausage's" Missing Ingredients: Investigating the Validity of Reliability Generalization Study Design.

    ERIC Educational Resources Information Center

    Romano, Jeanine; Kromrey, Jeffrey D.

    The purpose of this study was to examine the potential impact of selected methodological factors on the validity of conclusions from reliability generalization (RG) studies. The study focused on four factors; (1) missing data in the primary studies; (2) transformation of sample reliability estimates; (3) use of sample weights for estimating mean…

  4. Study of turboprop systems reliability and maintenance costs

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The overall reliability and maintenance costs (R&MC's) of past and current turboprop systems were examined. Maintenance cost drivers were found to be scheduled overhaul (40%), lack of modularity particularly in the propeller and reduction gearbox, and lack of inherent durability (reliability) of some parts. Comparisons were made between the 501-D13/54H60 turboprop system and the widely used JT8D turbofan. It was found that the total maintenance cost per flight hour of the turboprop was 75% higher than that of the JT8D turbofan. Part of this difference was due to propeller and gearbox costs being higher than those of the fan and reverser, but most of the difference was in the engine core where the older technology turboprop core maintenance costs were nearly 70 percent higher than for the turbofan. The estimated maintenance cost of both the advanced turboprop and advanced turbofan were less than the JT8D. The conclusion was that an advanced turboprop and an advanced turbofan, using similar cores, will have very competitive maintenance costs per flight hour.

  5. Towards early software reliability prediction for computer forensic tools (case study).

    PubMed

    Abu Talib, Manar

    2016-01-01

    Versatility, flexibility and robustness are essential requirements for software forensic tools. Researchers and practitioners need to put more effort into assessing this type of tool. A Markov model is a robust means for analyzing and anticipating the functioning of an advanced component based system. It is used, for instance, to analyze the reliability of the state machines of real time reactive systems. This research extends the architecture-based software reliability prediction model for computer forensic tools, which is based on Markov chains and COSMIC-FFP. Basically, every part of the computer forensic tool is linked to a discrete time Markov chain. If this can be done, then a probabilistic analysis by Markov chains can be performed to analyze the reliability of the components and of the whole tool. The purposes of the proposed reliability assessment method are to evaluate the tool's reliability in the early phases of its development, to improve the reliability assessment process for large computer forensic tools over time, and to compare alternative tool designs. The reliability analysis can assist designers in choosing the most reliable topology for the components, which can maximize the reliability of the tool and meet the expected reliability level specified by the end-user. The approach of assessing component-based tool reliability in the COSMIC-FFP context is illustrated with the Forensic Toolkit Imager case study.

  6. A Study of DSN Traveling Wave Maser System Reliability

    NASA Technical Reports Server (NTRS)

    Stevens, R.; Wiggins, C. P.

    1984-01-01

    Reliability and availability characteristics of the DSN traveling wave maser (TWM) Assemblies are reported for the years 1981 through 1983, the charcteristics determined are: mean time between failures (MTBF) - 1200 hours; mean time to restore service (MTTRS) - 2.5 hours; and availability - 99.83%. The TWM MTBF is very good as compared to other DSN subsystems and assemblies. The TWM MTTRS is currently about three times as long as the average of other DSN subsystems. The dominant cause of TWM failures is contamination of the helium gas in the closed cycle refrigerators. Station configurations that do not provide TWM redundancy are subject to reception outages for long periods of time. Recommendations are made to improve the TWM Assembly availability characteristics for future mission support operations.

  7. Sensitivity study of reliable, high-throughput resolution metricsfor photoresists

    SciTech Connect

    Anderson, Christopher N.; Naulleau, Patrick P.

    2007-07-30

    The resolution of chemically amplified resists is becoming an increasing concern, especially for lithography in the extreme ultraviolet (EUV) regime. Large-scale screening and performance-based down-selection is currently underway to identify resist platforms that can support shrinking feature sizes. Resist screening efforts, however, are hampered by the absence of reliable resolution metrics that can objectively quantify resist resolution in a high-throughput fashion. Here we examine two high-throughput metrics for resist resolution determination. After summarizing their details and justifying their utility, we characterize the sensitivity of both metrics to two of the main experimental uncertainties associated with lithographic exposure tools, namely: limited focus control and limited knowledge of optical aberrations. For an implementation at EUV wavelengths, we report aberration and focus limited error bars in extracted resolution of {approx} 1.25 nm RMS for both metrics making them attractive candidates for future screening and down-selection efforts.

  8. System Level spatial-frequency EEG changes coincident with a 90-day cognitive-behavioral therapy program for couples in relationship distress.

    PubMed

    DuRousseau, Donald R; Beeton, Theresa A

    2015-09-01

    Evaluating relationship intervention programs traditionally involves the use of self-report surveys or observational studies to assess changes in behavior. Instead, to investigate intervention-related changes in behavior, our study evaluates spatial-frequency electroencephalography (EEG) patterns from the brains of couples participating in an Imago Relationship workshop and 12 weeks of group counseling sessions lasting approximately 90 days. This explorative study recorded 32-channel EEGs from nine committed distressed couples prior to, during and immediately following the Imago Relationship Therapy program. A repeated measures t-Test approach was applied to investigate if significant group level brain pattern changes could be identified in key resting state networks in the brains of the participants that could be correlated with changes in relationship outcome. The study results show that significant reductions in EEG power in the alpha2, beta3 and gamma bands were evident in the averaged brain activity in the pre-frontal, frontal and temporal-parietal cortices that are anatomically associated with the frontal executive, default mode and salience networks of the human brain. Our current understanding of system level neural connectivity and network dynamics strongly indicates that each of these systems is integrally required in learning and implementing a complex communication process taught in the Imago intervention. Thus, a high degree of hemispheric lateralization is consistent with our understanding of language function and mood regulation in the brain and is consistent with recent research into the use of resting frontal EEG asymmetry as an indicator of behavioral changes in distressed couples undergoing a program for relationship improvement. Although preliminary, these results further indicate that the EEG is an inexpensive and easily quantifiable measure, and possibly predictor, of behavioral changes in response to a cognitive behavioral intervention.

  9. Final report for CCS cross-layer reliability visioning study

    SciTech Connect

    Quinn, Heather M; Dehon, Andre; Carter, Nicj

    2010-12-20

    The geometric rate of improvement of transistor size and integrated circuit performance known as Moore's Law has been an engine of growth for our economy, enabling new products and services, creating new value and wealth, increasing safety, and removing menial tasks from our daily lives. Affordable, highly integrated components have enabled both life-saving technologies and rich entertainment applications. Anti-lock brakes, insulin monitors, and GPS-enabled emergency response systems save lives. Cell phones, internet appliances, virtual worlds, realistic video games, and mp3 players enrich our lives and connect us together. Over the past 40 years of silicon scaling, the increasing capabilities of inexpensive computation have transformed our society through automation and ubiquitous communications. Looking forward, increasing unpredictability threatens our ability to continue scaling integrated circuits at Moore's Law rates. As the transistors and wires that make up integrated circuits become smaller, they display both greater differences in behavior among devices designed to be identical and greater vulnerability to transient and permanent faults. Conventional design techniques expend energy to tolerate this unpredictability by adding safety margins to a circuit's operating voltage, clock frequency or charge stored per bit. However, the rising energy costs needed to compensate for increasing unpredictability are rapidly becoming unacceptable in today's environment where power consumption is often the limiting factor on integrated circuit performance and energy efficiency is a national concern. Reliability and energy consumption are both reaching key inflection points that, together, threaten to reduce or end the benefits of feature size reduction. To continue beneficial scaling, we must use a cross-layer, Jull-system-design approach to reliability. Unlike current systems, which charge every device a substantial energy tax in order to guarantee correct operation in

  10. An Approach to Studying the Reliability of Microgravity Experiments

    NASA Technical Reports Server (NTRS)

    Thaggard, Michael; Morilak, Daniel P.

    1994-01-01

    The identification of key factors that influence the nonsuccess of experiments conducted under microgravity conditions will aid in the planning, design, and implementation of future space shuttle experiments, as well as other microgravity experiments (i.e., experiments conducted on the space station). Similarly, knowledge of the experiments' reliability will assist in forecasting the success of forthcoming experiments. Since a relatively large number of space shuttle experiments have been conducted to date, a substantial pool of data exists for assessing the possible causes or factors which influence experiment nonsuccesses. This report details the task being undertaken at NASA Lewis Research Center (LeRC) to measure the space shuttle experiments' nonsuccess trends and identify causes that significantly affect their performance. It addresses the activities associated with correlating experiment macro-factors with experiment nonsuccesses. The development and implementation of a microgravity database to be used for tracking and correlating experiment nonsuccess factors, as well as the criteria for measuring experiment success and nonsuccess, are also discussed.

  11. Study on the Validity and Reliability of Melbourne Decision Making Scale in Turkey

    ERIC Educational Resources Information Center

    Çolakkadioglu, Oguzhan; Deniz, M. Engin

    2015-01-01

    This study is to analyze the validity and reliability of Melbourne Decision Making Questionnaire (MDMQ). The sample consisted of 650 university students. The structural validity of the MDMQ, as well as correlations among its sub-scales, measure-bound validity, internal consistency, item total correlations and test-retest reliability coefficients…

  12. Retest Reliability of the Rosenzweig Picture-Frustration Study and Similar Semiprojective Techniques

    ERIC Educational Resources Information Center

    Rosenzweig, Saul; And Others

    1975-01-01

    The research dealing with the reliability of the Rosenzweig Picture-Frustration Study is surveyed. Analysis of various split-half, and retest procedures are reviewed and their relative effectiveness evaluated. Reliability measures as applied to projective techniques in general are discussed. (Author/DEP)

  13. Stability of the Reliability of LibQUAL+ (tm) Scores: A Reliability Generalization Meta-Analysis Study.

    ERIC Educational Resources Information Center

    Thompson, Bruce; Cook, Collen

    2002-01-01

    Conducted a reliability generalization meta-analysis of subscale and total scale scores on the Web-administered LibQUAL+ (tm) (Cook and others, 2002), a measure of library service quality. Data for 18,161 participants from 43 universities show that score reliabilities are remarkably invariant across campuses and different over groups. (SLD)

  14. Assessing the reliability of ecotoxicological studies: An overview of current needs and approaches.

    PubMed

    Moermond, Caroline; Beasley, Amy; Breton, Roger; Junghans, Marion; Laskowski, Ryszard; Solomon, Keith; Zahner, Holly

    2016-11-21

    In general, reliable studies are well designed and well performed, and enough details on study design and performance are reported to assess the study. For hazard and risk assessment in various legal frameworks, many different types of ecotoxicity studies need to be evaluated for reliability. These studies vary in study design, methodology, quality, and level of detail reported (e.g., reviews, peer-reviewed research papers, or industry-sponsored studies documented under Good Laboratory Practice [GLP] guidelines). Regulators have the responsibility to make sound and verifiable decisions and should evaluate each study for reliability in accordance with scientific principles regardless of whether they were conducted in accordance with GLP and/or standardized methods. Thus, a systematic and transparent approach is needed to evaluate studies for reliability. In this paper, 8 different methods for reliability assessment were compared using a number of attributes: categorical versus numerical scoring methods, use of exclusion and critical criteria, weighting of criteria, whether methods are tested with case studies, domain of applicability, bias toward GLP studies, incorporation of standard guidelines in the evaluation method, number of criteria used, type of criteria considered, and availability of guidance material. Finally, some considerations are given on how to choose a suitable method for assessing reliability of ecotoxicity studies. Integr Environ Assess Manag. ©2016 SETAC.

  15. How reliable are clinical systems in the UK NHS? A study of seven NHS organisations

    PubMed Central

    Franklin, Bryony Dean; Moorthy, Krishna; Cooke, Matthew W; Vincent, Charles

    2012-01-01

    Background It is well known that many healthcare systems have poor reliability; however, the size and pervasiveness of this problem and its impact has not been systematically established in the UK. The authors studied four clinical systems: clinical information in surgical outpatient clinics, prescribing for hospital inpatients, equipment in theatres, and insertion of peripheral intravenous lines. The aim was to describe the nature, extent and variation in reliability of these four systems in a sample of UK hospitals, and to explore the reasons for poor reliability. Methods Seven UK hospital organisations were involved; each system was studied in three of these. The authors took delivery of the systems' intended outputs to be a proxy for the reliability of the system as a whole. For example, for clinical information, 100% reliability was defined as all patients having an agreed list of clinical information available when needed during their appointment. Systems factors were explored using semi-structured interviews with key informants. Common themes across the systems were identified. Results Overall reliability was found to be between 81% and 87% for the systems studied, with significant variation between organisations for some systems: clinical information in outpatient clinics ranged from 73% to 96%; prescribing for hospital inpatients 82–88%; equipment availability in theatres 63–88%; and availability of equipment for insertion of peripheral intravenous lines 80–88%. One in five reliability failures were associated with perceived threats to patient safety. Common factors causing poor reliability included lack of feedback, lack of standardisation, and issues such as access to information out of working hours. Conclusions Reported reliability was low for the four systems studied, with some common factors behind each. However, this hides significant variation between organisations for some processes, suggesting that some organisations have managed to create

  16. Book Reading Motivation Scale: Reliability and Validity Study

    ERIC Educational Resources Information Center

    Katranci, Mehmet

    2015-01-01

    Book reading enhances the intellectual world of people. It is very important to know the factors that motivate children to read books as it will help to instill book reading habit in them. As such, the present study aims to develop a "Book Reading Motivation Scale" to determine elementary and secondary school students' reading…

  17. Virtual Environment Interpersonal Trust Scale: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Usta, Ertugrul

    2012-01-01

    The purpose of this study is in the process of interpersonal communication in virtual environments is available from the trust problem is to develop a measurement tool. Trust in the process of distance education today, and has been a factor to be investigated. People, who take distance education course, they could may remain within the process…

  18. An Overview of NASA Automotive Component Reliability Studies

    NASA Technical Reports Server (NTRS)

    Sampson, Michael J.

    2016-01-01

    The results of NASAs studies into the appropriateness of using US Automotive electronic parts in NASA spaceflight systems will be presented. The first part of the presentation provides an overview of the United States Automotive Electronics Councils AECQ standardization program, the second part provides a summary of the results of NASAs procurement and testing experiences and other lessons learned along with preliminary test results.

  19. An Overview Of NASA Automotive Component Reliability Studies

    NASA Technical Reports Server (NTRS)

    Sampson, Michael J.

    2016-01-01

    The results of NASAs studies into the appropriateness of using US Automotive electronic parts in NASA spaceflight systems will be presented. The first part of the presentation provides an overview of the United States Automotive Electronics Councils AECQ standardization program, the second part provides a summary of the results of NASAs procurement and testing experiences and other lessons learned along with preliminary test results.

  20. Evaluating the Reliability, Validity, and Usefulness of Education Cost Studies

    ERIC Educational Resources Information Center

    Baker, Bruce D.

    2006-01-01

    Recent studies that purport to estimate the costs of constitutionally adequate education have been described as either a "gold standard" that should guide legislative school finance policy design and judicial evaluation, or as pure "alchemy." Methods for estimating the cost of constitutionally adequate education can be roughly…

  1. Measuring steps with the Fitbit activity tracker: an inter-device reliability study.

    PubMed

    Dontje, Manon L; de Groot, Martijn; Lengton, Remko R; van der Schans, Cees P; Krijnen, Wim P

    2015-01-01

    Activity trackers like Fitbit are used for self-tracking of physical activity by an increasing number of individuals. Comparing physical activity scores with peers can contribute to the desired behavioural change. However, for meaningful social comparison a high inter-device reliability is paramount. This study aimed to determine the inter-device reliability of Fitbit activity trackers in measuring steps. Ten activity trackers (Fitbit Ultra) were worn by a single person (male, 46 years) during eight consecutive days. Inter-device reliability was assessed on three different levels of aggregation (minutes, hours, days) with various methods, including intra-class correlation coefficient (ICC), Bland-Altman plots, limits of agreement (LOA) and Mixed Model Analysis. Results showed that the inter-device reliability of the Fitbit in measuring steps is good at all levels of aggregation (minutes, hours, days), but especially when steps were measured per day. This implies that individuals can reliably compare their daily physical activity scores with peers.

  2. Remotely Operated Vehicle (ROV) Reliability Study. Phase 1.

    DTIC Science & Technology

    1987-12-01

    for long periods of time, becoming encrusted with coraline algae that covers both the shafts and their housings. Extra force is required to break...problems similar to those of coraline biofouling. [A study should be done to develop methods to prevent build up or to remove silts that can...in the final ROV assembly. 24 pq 1.8 Biofouling Build-up of Coraline Algae on Shafts and Seals The growth of certain coraline marine organisms of the

  3. Reliability of solar keratosis clinical diagnosis: A prospective study.

    PubMed

    Buinauskaite, Evelina; Makstiene, Jurgita; Buinauskiene, Jurate; Valiukeviciene, Skaidra

    2015-05-01

    Usually solar keratoses (SK) are diagnosed clinically. However other diseases may clinically present as erythematous macules, papules or patches on sun-exposed areas; therefore the histopathology remains the gold standard diagnostic tool. Our study, which assessed the efficacy of photodynamic therapy (PDT), showed that one in 20 clinically diagnosed SK lesions grade I-II identified by board-certified dermatologists were rosacea and only one in 40 were malignant lesions. These findings should be considered by clinicians who treat clinically diagnosed grade I-II SK without response to treatment or diagnose the recurrence of SK after PDT.

  4. Lamp reliability studies for improved satellite rubidium frequency standard

    NASA Technical Reports Server (NTRS)

    Frueholz, R. P.; Wun-Fogle, M.; Eckert, H. U.; Volk, C. H.; Jones, P. F.

    1982-01-01

    In response to the premature failure of Rb lamps used in Rb atomic clocks onboard NAVSTAR GPS satellites experimental and theoretical investigations into their failure mechanism were initiated. The primary goal of these studies is the development of an accelerated life test for future GPS lamps. The primary failure mechanism was identified as consumption of the lamp's Rb charge via direct interaction between Rb and the lamp's glass surface. The most effective parameters to accelerate the interaction between the Rb and the glass are felt to be RF excitation power and lamp temperature. Differential scanning calorimetry is used to monitor the consumption of Rb within a lamp as a function of operation time. This technique yielded base line Rb consumption data for GPS lamps operating under normal conditions.

  5. Reliability analysis of idealized tunnel support system using probability-based methods with case studies

    NASA Astrophysics Data System (ADS)

    Gharouni-Nik, Morteza; Naeimi, Meysam; Ahadi, Sodayf; Alimoradi, Zahra

    2014-06-01

    In order to determine the overall safety of a tunnel support lining, a reliability-based approach is presented in this paper. Support elements in jointed rock tunnels are provided to control the ground movement caused by stress redistribution during the tunnel drive. Main support elements contribute to stability of the tunnel structure are recognized owing to identify various aspects of reliability and sustainability in the system. The selection of efficient support methods for rock tunneling is a key factor in order to reduce the number of problems during construction and maintain the project cost and time within the limited budget and planned schedule. This paper introduces a smart approach by which decision-makers will be able to find the overall reliability of tunnel support system before selecting the final scheme of the lining system. Due to this research focus, engineering reliability which is a branch of statistics and probability is being appropriately applied to the field and much effort has been made to use it in tunneling while investigating the reliability of the lining support system for the tunnel structure. Therefore, reliability analysis for evaluating the tunnel support performance is the main idea used in this research. Decomposition approaches are used for producing system block diagram and determining the failure probability of the whole system. Effectiveness of the proposed reliability model of tunnel lining together with the recommended approaches is examined using several case studies and the final value of reliability obtained for different designing scenarios. Considering the idea of linear correlation between safety factors and reliability parameters, the values of isolated reliabilities determined for different structural components of tunnel support system. In order to determine individual safety factors, finite element modeling is employed for different structural subsystems and the results of numerical analyses are obtained in

  6. MNOS/SOS radiation hardness performance and reliability study

    NASA Astrophysics Data System (ADS)

    Hampton, F. L.; Cricchi, J. R.

    1982-05-01

    In this investigation the endurance-retention characteristics of fast-write MNOS memory structure, and radiation tolerance of metal-gate dual-dielectric and polysilicon-gate all-oxide devices have been evaluated. Writing and clearing speed have been studied with respect to the NH3:SiH4 ratio (APCVD), and NH3:SiC12H2 ratio (LPCVD). The films deposited with a low NH3:SiC12 ratios could be written and cleared with shorter pulse widths; however, a degradation in retention was observed. An improvement in the endurance retention product of a drain source protected transistor structure has been realized by oxidizing the memory nitride followed by an H2 anneal immediately after deposition. The film was deposited with a LPCVD reactor at 750 deg with a NH3:SiC12H2 ratio of 9:1. Oxidation was performed in steam at 900 C, as was the subsequent H2 anneal. The effect of total dose radiation was found to be more severe for a positive bias. The all oxide polysilicon gate transistor structures were observed to be relatively soft, however results from capacitor structures shows promise in developing a radiation tolerant polysilicon-gate all-oxide gate structure.

  7. Study of Fuze Structure and Reliability Design Based on the Direct Search Method

    NASA Astrophysics Data System (ADS)

    Lin, Zhang; Ning, Wang

    2017-03-01

    Redundant design is one of the important methods to improve the reliability of the system, but mutual coupling of multiple factors is often involved in the design. In my study, Direct Search Method is introduced into the optimum redundancy configuration for design optimization, in which, the reliability, cost, structural weight and other factors can be taken into account simultaneously, and the redundant allocation and reliability design of aircraft critical system are computed. The results show that this method is convenient and workable, and applicable to the redundancy configurations and optimization of various designs upon appropriate modifications. And this method has a good practical value.

  8. A study of the longevity and operational reliability of Goddard Spacecraft, 1960-1980

    NASA Technical Reports Server (NTRS)

    Shockey, E. F.

    1981-01-01

    Compiled data regarding the design lives and lifetimes actually achieved by 104 orbiting satellites launched by the Goddard Spaceflight Center between the years 1960 and 1980 is analyzed. Historical trends over the entire 21 year period are reviewed, and the more recent data is subjected to an examination of several key parameters. An empirical reliability function is derived, and compared with various mathematical models. Data from related studies is also discussed. The results provide insight into the reliability history of Goddard spacecraft an guidance for estimating the reliability of future programs.

  9. Reliability of anthropometric measurements in European preschool children: the ToyBox-study.

    PubMed

    De Miguel-Etayo, P; Mesana, M I; Cardon, G; De Bourdeaudhuij, I; Góźdź, M; Socha, P; Lateva, M; Iotova, V; Koletzko, B V; Duvinage, K; Androutsos, O; Manios, Y; Moreno, L A

    2014-08-01

    The ToyBox-study aims to develop and test an innovative and evidence-based obesity prevention programme for preschoolers in six European countries: Belgium, Bulgaria, Germany, Greece, Poland and Spain. In multicentre studies, anthropometric measurements using standardized procedures that minimize errors in the data collection are essential to maximize reliability of measurements. The aim of this paper is to describe the standardization process and reliability (intra- and inter-observer) of height, weight and waist circumference (WC) measurements in preschoolers. All technical procedures and devices were standardized and centralized training was given to the fieldworkers. At least seven children per country participated in the intra- and inter-observer reliability testing. Intra-observer technical error ranged from 0.00 to 0.03 kg for weight and from 0.07 to 0.20 cm for height, with the overall reliability being above 99%. A second training was organized for WC due to low reliability observed in the first training. Intra-observer technical error for WC ranged from 0.12 to 0.71 cm during the first training and from 0.05 to 1.11 cm during the second training, and reliability above 92% was achieved. Epidemiological surveys need standardized procedures and training of researchers to reduce measurement error. In the ToyBox-study, very good intra- and-inter-observer agreement was achieved for all anthropometric measurements performed.

  10. Reliability of hypothalamic–pituitary–adrenal axis assessment methods for use in population-based studies

    PubMed Central

    Wand, Gary S.; Malhotra, Saurabh; Kamel, Ihab; Horton, Karen

    2013-01-01

    Population-based studies have been hampered in exploring hypothalamic–pituitary–adrenal axis (HPA) activity as a potential explanatory link between stress-related and metabolic disorders due to their lack of incorporation of reliable measures of chronic cortisol exposure. The purpose of this review is to summarize current literature on the reliability of HPA axis measures and to discuss the feasibility of performing them in population-based studies. We identified articles through PubMed using search terms related to cortisol, HPA axis, adrenal imaging, and reliability. The diurnal salivary cortisol curve (generated from multiple salivary samples from awakening to midnight) and 11 p.m. salivary cortisol had the highest between-visit reliabilities (r = 0.63–0.84 and 0.78, respectively). The cortisol awakening response and dexamethasone-suppressed cortisol had the next highest between-visit reliabilities (r = 0.33–0.67 and 0.42–0.66, respectively). Based on our own data, the inter-reader reliability (rs) of adrenal gland volume from non-contrast CT was 0.67–0.71 for the left and 0.47–0.70 for the right adrenal glands. While a single 8 a.m. salivary cortisol is one of the easiest measures to perform, it had the lowest between-visit reliability (R = 0.18–0.47). Based on the current literature, use of sampling multiple salivary cortisol measures across the diurnal curve (with awakening cortisol), dexamethasone-suppressed cortisol, and adrenal gland volume are measures of HPA axis tone with similar between-visit reliabilities which likely reflect chronic cortisol burden and are feasible to perform in population-based studies. PMID:21533585

  11. Reliability of neuroanatomical measurements in a multisite longitudinal study of youth at risk for psychosis.

    PubMed

    Cannon, Tyrone D; Sun, Frank; McEwen, Sarah Jacobson; Papademetris, Xenophon; He, George; van Erp, Theo G M; Jacobson, Aron; Bearden, Carrie E; Walker, Elaine; Hu, Xiaoping; Zhou, Lei; Seidman, Larry J; Thermenos, Heidi W; Cornblatt, Barbara; Olvet, Doreen M; Perkins, Diana; Belger, Aysenil; Cadenhead, Kristin; Tsuang, Ming; Mirzakhanian, Heline; Addington, Jean; Frayne, Richard; Woods, Scott W; McGlashan, Thomas H; Constable, R Todd; Qiu, Maolin; Mathalon, Daniel H; Thompson, Paul; Toga, Arthur W

    2014-05-01

    Multisite longitudinal neuroimaging designs are used to identify differential brain structural change associated with onset or progression of disease. The reliability of neuroanatomical measurements over time and across sites is a crucial aspect of power in such studies. Prior work has found that while within-site reliabilities of neuroanatomical measurements are excellent, between-site reliability is generally more modest. Factors that may increase between-site reliability include standardization of scanner platform and sequence parameters and correction for between-scanner variations in gradient nonlinearities. Factors that may improve both between- and within-site reliability include use of registration algorithms that account for individual differences in cortical patterning and shape. In this study 8 healthy volunteers were scanned twice on successive days at 8 sites participating in the North American Prodrome Longitudinal Study (NAPLS). All sites employed 3 Tesla scanners and standardized acquisition parameters. Site accounted for 2 to 30% of the total variance in neuroanatomical measurements. However, site-related variations were trivial (<1%) among sites using the same scanner model and 12-channel coil or when correcting for between-scanner differences in gradient nonlinearity and scaling. Adjusting for individual differences in sulcal-gyral geometries yielded measurements with greater reliabilities than those obtained using an automated approach. Neuroimaging can be performed across multiple sites at the same level of reliability as at a single site, achieving within- and between-site reliabilities of 0.95 or greater for gray matter density in the majority of voxels in the prefrontal and temporal cortical surfaces as well as for the volumes of most subcortical structures.

  12. Control of posture during tasks representing common work-related postures - a reliability study.

    PubMed

    Mani, Ramakrishnan; Milosavljevic, Stephan; Sullivan, S John

    2015-01-01

    Assessment of control of posture using a task battery that represents work-related postural conditions is highly recommended for providing a comprehensive understanding of collective postural demands. However, dearth of evidence exists on the reliability of a task battery, thus precluding its use as an outcome measure in field research. This study investigated the intrasession reliability and systematic variation of force plate derived centre of pressure (COP) measures obtained during repeated performance of a task battery (lifting task, limits of stability and bipedal and unipedal stance). COP signals obtained during each task performance were processed to derive various time-domain COP measures. Statistical analyses revealed that 13 of the 19 COP measures displayed excellent relative (ICC(2,3) ≥ 0.75) and acceptable absolute reliability (SEM%: ≤ 10). Although COP measures displayed systematic variation, the differences were less or equal to the measurement error, except COP measures of unipedal stance and limits of stability. The chosen task battery is reliable and can be used for comprehensive evaluation of control of posture, in both field and laboratory research. Practitioner Summary: Repeated evaluation of multiple tasks together sequentially could introduce measurement variability. This study investigated intrasession reliability of a task battery representing common work-related postures. The chosen task battery was found to be reliable with acceptable measurement error and can be used in field research settings for evaluation of control of posture.

  13. Reliability-based structural optimization: A proposed analytical-experimental study

    NASA Technical Reports Server (NTRS)

    Stroud, W. Jefferson; Nikolaidis, Efstratios

    1993-01-01

    An analytical and experimental study for assessing the potential of reliability-based structural optimization is proposed and described. In the study, competing designs obtained by deterministic and reliability-based optimization are compared. The experimental portion of the study is practical because the structure selected is a modular, actively and passively controlled truss that consists of many identical members, and because the competing designs are compared in terms of their dynamic performance and are not destroyed if failure occurs. The analytical portion of this study is illustrated on a 10-bar truss example. In the illustrative example, it is shown that reliability-based optimization can yield a design that is superior to an alternative design obtained by deterministic optimization. These analytical results provide motivation for the proposed study, which is underway.

  14. Curriculum Design Orientations Preference Scale of Teachers: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Bas, Gokhan

    2013-01-01

    The purpose of this study was to develop a valid and reliable scale for preferences of teachers in regard of their curriculum design orientations. Because there was no scale development study similar to this one in Turkey, it was considered as an urgent need to develop such a scale in the study. The sample of the research consisted of 300…

  15. Reliability of lower extremity muscle strength measurements with handheld dynamometry in stroke patients during the acute phase: a pilot reliability study

    PubMed Central

    Yen, Hsiao-Ching; Luh, Jer-Junn; Teng, Ting; Pan, Guan-Shuo; Chen, Wen-Shiang; Hsun, Chiang-Chang; Jeng, Jiann-Shing

    2017-01-01

    [Purpose] No literature has described a suitable method for measuring muscle strength in a supine position during acute phase after stroke. This study investigated the feasibility and reliability of using a commercial handheld dynamometer to measure the muscle strengths of the hip flexor, knee extensor, and dorsiflexor in the supine position with a modified method for patients at a stroke intensive care center within 7 days of stroke onset. [Subjects and Methods] Fifteen persons with acute stroke participated in this cross-sectional study. For each patient, the muscle strengths of the hip flexors, knee extensors, and dorsiflexors were measured twice by two testers on the same day. Each patient was re-tested at the same time of day one day later. Inter-rater and test-retest reliability were then determined by the intraclass correlation coefficients (ICCs). [Results] For the three muscle groups, the inter-rater reliability ICCs were all 0.99 and the test-retest reliability ICCs were greater than 0.85. The investigated method thus has good inter-rater reliability and high agreement between the test-retest measurements, with acceptable measurement errors. [Conclusion] The modified method using a handheld dynamometer to test the muscle strength of acute stroke patients is a feasible and reliable method for clinical use. PMID:28265165

  16. A Validation and Reliability Study of Community Service Activities Scale in Turkey: A Social Evaluation

    ERIC Educational Resources Information Center

    Demir, Özden; Kaya, Halil Ibrahim; Tasdan, Murat

    2014-01-01

    The purpose of this study is to test the reliability and validity of Community Service Activities Scale (CSAS) developed by Demir, Kaya and Tasdan (2012) with a view to identify perceptions of Faculty of Education students regarding community service activities. The participants of the study are 313 randomly chosen students who attend six…

  17. Turkish Adaptation of the Mentorship Effectiveness Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Yirci, Ramazan; Karakose, Turgut; Uygun, Harun; Ozdemir, Tuncay Yavuz

    2016-01-01

    The purpose of this study is to adapt the Mentoring Relationship Effectiveness Scale to Turkish, and to conduct validity and reliability tests regarding the scale. The study group consisted of 156 university science students receiving graduate education. Construct validity and factor structure of the scale was analyzed first through exploratory…

  18. Reliable Digit Span: A Systematic Review and Cross-Validation Study

    ERIC Educational Resources Information Center

    Schroeder, Ryan W.; Twumasi-Ankrah, Philip; Baade, Lyle E.; Marshall, Paul S.

    2012-01-01

    Reliable Digit Span (RDS) is a heavily researched symptom validity test with a recent literature review yielding more than 20 studies ranging in dates from 1994 to 2011. Unfortunately, limitations within some of the research minimize clinical generalizability. This systematic review and cross-validation study was conducted to address these…

  19. The Validity and Reliability Studies of the Computer Anxiety Scale on Educational Administrators (CAS-EA)

    ERIC Educational Resources Information Center

    Agaoglu, Esmahan; Ceyhan, Esra; Ceyhan, Aykut; Simsek, Yucel

    2008-01-01

    This study aims at investigating the validity and reliability studies of the "Computer Anxiety Scale" (Ceyhan & Gurcan Namlu, 2000) on educational administrators. The data gathered from 143 educational administrators of state schools located in Eskisehir show that the scale consists of 2 factors. The first of these factors, affective…

  20. Adaptation of Organizational Justice in Sport Scale into Turkish Language: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Sayin, Ayfer; Sahin, Mustafa Yasar

    2017-01-01

    The present study aimed to provide a Turkish adaptation of the Organizational Justice in Sport Scale and perform reliability and validity studies. Answers provided by 260 participants who work as football, male basketball and female basketball coaches in National Collegiate Athletic Association (NCAA) were analysed using the original scale that…

  1. A Validity and Reliability Study of the Online Cooperative Learning Attitude Scale (OCLAS)

    ERIC Educational Resources Information Center

    Korkmaz, Ozgen

    2012-01-01

    Determination of students' attitudes towards online cooperative learning is an important issue, which has not been studied adequately. In the literature, there are few scales to measure the attitude towards online cooperative learning for which validity and reliability have been proven. The main purpose of this study is to develop an attitude…

  2. Cyber Victim and Bullying Scale: A Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Cetin, Bayram; Yaman, Erkan; Peker, Adem

    2011-01-01

    The purpose of this study is to develop a reliable and valid scale, which determines cyber victimization and bullying behaviors of high school students. Research group consisted of 404 students (250 male, 154 male) in Sakarya, in 2009-2010 academic years. In the study sample, mean age is 16.68. Content validity and face validity of the scale was…

  3. A Validity and Reliability Study on the Development of the Values Scale in Turkey

    ERIC Educational Resources Information Center

    Dilmac, Bulent; Aricak, Osman Tolga; Cesur, Sevim

    2014-01-01

    The purpose of the present study is to examine the initial psychometric properties of the Values Scale for adults. While developing the first stage of the Values Scale, open-ended data on the values held by 216 university students were obtained. During the second stage, the validity and reliability studies of the 60-item Values Scale obtained by…

  4. A Validity and Reliability Study of the Motivated Strategies for Learning Questionnaire

    ERIC Educational Resources Information Center

    Erturan Ilker, Gökçe; Arslan, Yunus; Demirhan, Giyasettin

    2014-01-01

    The aim of this study is to determine the validity and reliability of the Motivated Strategies for Learning Questionnaire (MSLQ) for high school students. In total, 1605 students (829 girls, 776 boys, average age = 15.67 ± 1.19) from three different high schools in the central district of Ankara voluntarily participated in the study. The MSLQ was…

  5. Depression, Anxiety and Stress Scale (DASS): The Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Basha, Ertan; Kaya, Mehmet

    2016-01-01

    The purpose of this study is to examine validity and reliability of the Albanian version of the Depression, Anxiety and Stress Scale (DASS), which is developed by Lovibond and Lovibond (1995). The sample of this study is consisted of 555 subjects who were living in Kosovo. The results of confirmatory factor analysis indicated 42 items loaded on…

  6. Developing a Scale for Innovation Management at Schools: A Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Bulbul, Tuncer

    2012-01-01

    The purpose of this study is to develop a valid and reliable assessment tool for use in determining the competency beliefs of school administrators about innovation management. The scale applied to a study group of 216 school administrators, after work Centered on assessing intelligibility and specialized opinion. Exploratory and confirmatory…

  7. The Scales of Psychological Well-Being: A Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Akin, Ahmet

    2008-01-01

    This study investigated the validity and reliability of the Turkish version of the Scales of Psychological Well-being (Ryff, 1989a). The sample of the study consists of 1214 university students. Results of language equivalency showed that correlations between the Turkish and English forms were 0.94 for autonomy, 0.97 for environmental mastery,…

  8. Water Awareness Scale for Pre-Service Science Teachers: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Filik Iscen, Cansu

    2015-01-01

    The role of teachers in the formation of environmentally sensitive behaviors in students is quite high. Thus, the water awareness of teachers, who represent role models for students, is rather important. The main purpose of this study is to identify the reliability and validity study outcomes of the Water Awareness Scale, which was developed to…

  9. Test-retest reliability and factor stability of the behavioral evaluation for epidemiology studies test battery.

    PubMed

    Echeverria, Diana; Heyer, Nicholas J; Bittner, Alvan C; Rohlman, Diane; Woods, James S

    2002-12-01

    The Behavioral Evaluation for Epidemiology Studies test battery uses touch-screen technology and novel methodologies to enhance neurobehavioral assessment. Scores generally show differential stability from the first trial with individual test reliabilities at or above .80 when normalized to a 3-min. administration. Six highly reliable (r > or = .87) factors were identified that cover functions known to be sensitive to neurotoxicants and physical exposures. These results strongly support recommendation of the new test battery for use in repeated-measures epidemiologic studies where first trial stability is desired.

  10. Sample size requirements for the design of reliability studies: precision consideration.

    PubMed

    Shieh, Gwowen

    2014-09-01

    In multilevel modeling, the intraclass correlation coefficient based on the one-way random-effects model is routinely employed to measure the reliability or degree of resemblance among group members. To facilitate the advocated practice of reporting confidence intervals in future reliability studies, this article presents exact sample size procedures for precise interval estimation of the intraclass correlation coefficient under various allocation and cost structures. Although the suggested approaches do not admit explicit sample size formulas and require special algorithms for carrying out iterative computations, they are more accurate than the closed-form formulas constructed from large-sample approximations with respect to the expected width and assurance probability criteria. This investigation notes the deficiency of existing methods and expands the sample size methodology for the design of reliability studies that have not previously been discussed in the literature.

  11. Reliable multicast for the Grid: a case study in experimental computer science.

    PubMed

    Nekovee, Maziar; Barcellos, Marinho P; Daw, Michael

    2005-08-15

    In its simplest form, multicast communication is the process of sending data packets from a source to multiple destinations in the same logical multicast group. IP multicast allows the efficient transport of data through wide-area networks, and its potentially great value for the Grid has been highlighted recently by a number of research groups. In this paper, we focus on the use of IP multicast in Grid applications, which require high-throughput reliable multicast. These include Grid-enabled computational steering and collaborative visualization applications, and wide-area distributed computing. We describe the results of our extensive evaluation studies of state-of-the-art reliable-multicast protocols, which were performed on the UK's high-speed academic networks. Based on these studies, we examine the ability of current reliable multicast technology to meet the Grid's requirements and discuss future directions.

  12. Reliability training

    NASA Technical Reports Server (NTRS)

    Lalli, Vincent R. (Editor); Malec, Henry A. (Editor); Dillard, Richard B.; Wong, Kam L.; Barber, Frank J.; Barina, Frank J.

    1992-01-01

    Discussed here is failure physics, the study of how products, hardware, software, and systems fail and what can be done about it. The intent is to impart useful information, to extend the limits of production capability, and to assist in achieving low cost reliable products. A review of reliability for the years 1940 to 2000 is given. Next, a review of mathematics is given as well as a description of what elements contribute to product failures. Basic reliability theory and the disciplines that allow us to control and eliminate failures are elucidated.

  13. Development of a Valid and Reliable Knee Articular Cartilage Condition–Specific Study Methodological Quality Score

    PubMed Central

    Harris, Joshua D.; Erickson, Brandon J.; Cvetanovich, Gregory L.; Abrams, Geoffrey D.; McCormick, Frank M.; Gupta, Anil K.; Verma, Nikhil N.; Bach, Bernard R.; Cole, Brian J.

    2014-01-01

    Background: Condition-specific questionnaires are important components in evaluation of outcomes of surgical interventions. No condition-specific study methodological quality questionnaire exists for evaluation of outcomes of articular cartilage surgery in the knee. Purpose: To develop a reliable and valid knee articular cartilage–specific study methodological quality questionnaire. Study Design: Cross-sectional study. Methods: A stepwise, a priori–designed framework was created for development of a novel questionnaire. Relevant items to the topic were identified and extracted from a recent systematic review of 194 investigations of knee articular cartilage surgery. In addition, relevant items from existing generic study methodological quality questionnaires were identified. Items for a preliminary questionnaire were generated. Redundant and irrelevant items were eliminated, and acceptable items modified. The instrument was pretested and items weighed. The instrument, the MARK score (Methodological quality of ARticular cartilage studies of the Knee), was tested for validity (criterion validity) and reliability (inter- and intraobserver). Results: A 19-item, 3-domain MARK score was developed. The 100-point scale score demonstrated face validity (focus group of 8 orthopaedic surgeons) and criterion validity (strong correlation to Cochrane Quality Assessment score and Modified Coleman Methodology Score). Interobserver reliability for the overall score was good (intraclass correlation coefficient [ICC], 0.842), and for all individual items of the MARK score, acceptable to perfect (ICC, 0.70-1.000). Intraobserver reliability ICC assessed over a 3-week interval was strong for 2 reviewers (≥0.90). Conclusion: The MARK score is a valid and reliable knee articular cartilage condition–specific study methodological quality instrument. Clinical Relevance: This condition-specific questionnaire may be used to evaluate the quality of studies reporting outcomes of

  14. Ultrasonography for the assessment of the upper trapezius properties in healthy females: a reliability study

    PubMed Central

    Adigozali, Hakimeh; Shadmehr, Azadeh; Ebrahimi, Esmail; Rezasoltani, Asghar; Naderi, Farrokh

    2016-01-01

    Summary Background to date, an assessment of morphometric features, muscle stiffness and blood flow in the upper trapezius among healthy females at rest and contraction states has not been conducted. So, in the current research, the intra-rater reliability of ultrasonographic features of upper trapezius in healthy females was examined. Method in this study stiffness and thickness of the upper trapezius in rest and contraction states were measured by ultrasonography on 12 healthy female subjects (28.33±5.05 years old). Color Doppler imaging was used to assess muscle circulation in the rest state only. Every step and calculation of measurements was repeated 3 times with the same rater. Therefore, in total 36 measurements were done for each variable. Results according to the analysis, the value of intra class correlation coefficient (ICC) for total variables showed an excellent level of reliability. Thickness at contraction had maximum reliability (ICC= 0.993) and Minimum Diastolic Velocity had the lowest reliability (ICC=0.771). Conclusions the results of current research demonstrated that real time ultrasonography is a reliable method for measurement of various parameters of upper trapezius, including morphometric features, its stiffness and blood supply in non-symptomatic females. These mentioned variables can likely be used for objective assessment and provide numerical reference value for clinical plans. PMID:27331047

  15. Is afternoon cortisol more reliable than waking cortisol in association studies of children with an ASD?

    PubMed

    Sharpley, Christopher F; Bitsika, Vicki; Andronicos, Nicholas M; Agnew, Linda L

    2016-03-01

    Salivary cortisol may be used as a biomarker of stress and anxiety in children with an Autism Spectrum Disorder (ASD) and is particularly valuable in studies of the association between stress-related cortisol concentrations and other factors such as comorbid disorders or aspects of the ASD phenotype. Although protocols for the collection of cortisol shortly after waking are often based on the assumption of the presence of a diurnal rhythm in cortisol, that rhythm may not be as reliable in children with an ASD as in non-ASD children. Alternatively, collecting cortisol during the afternoon may represent a more reliable procedure with less inter-participant variability.

  16. Are they family or friends? Social support instrument reliability in studying older lesbians.

    PubMed

    Gabrielson, Marcena L; Holston, Ezra C; Dyck, Mary J

    2014-01-01

    We know little about the support needs and health of older lesbians because participant sexual identity has typically not been identified in aging studies. The Lubben Social Network Scale, Revised (LSNS-R) is found widely reliable for testing perceived social support among elders but has never been tested with an exclusively lesbian population. This pilot tested the instrument with an exclusively lesbian population in the Midwest. Our analysis suggests it may not be reliable with this population, even with minor modifications that were made. Further examination adding a category for "family of choice" is warranted and supported by the originator of the tool.

  17. Slicing the Attitude Pie: A Validity and Reliability Study of a New Attitude Assessment Technique.

    ERIC Educational Resources Information Center

    Lull, James T.; Cappella, Joseph N.

    This paper introduces a new measure of attitude, the "attitude pie," which attempts to separate true neutrality from degree of indifference while providing an evaluation score on the issue being judged. A large reliability-validity study involving ten attitude traits, four different methods, and over one hundred subjects at three different times…

  18. Environmental Affective Dispositions Scale (EADS): The Study of Validity and Reliability and Adaptation to Turkish

    ERIC Educational Resources Information Center

    Fettahlioglu, Pinar; Timur, Serkan; Timur, Betül

    2016-01-01

    The aim of this study is to conduct a research under circumstances of Turkey about the validity and reliability of the Affective Tendencies towards Environmental Scale prepared by Yavetz, Goldman and Pe'er (2009). The translation of this scale to Turkish was done by the researchers and language specialists. And then, the scale was evaluated by the…

  19. Value-Eroding Teacher Behaviors Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Arseven, Zeynep; Kiliç, Abdurrahman; Sahin, Seyma

    2016-01-01

    In the present study, it is aimed to develop a valid and reliable scale for determining value-eroding behaviors of teachers, hence their values of judgment. The items of the "Value-eroding Teacher Behaviors Scale" were designed in the form of 5-point likert type rating scale. The exploratory factor analysis (EFA) was conducted to…

  20. Adaptation of Internet Addiction Scale in Azerbaijani Language: A Validity-Reliability and Prevalence Study

    ERIC Educational Resources Information Center

    Kerimova, Melek; Gunuc, Selim

    2016-01-01

    The purpose of the present paper was to adapt Gunuc and Kayri's (2010) "Internet Addiction Scale," with show validity and reliability for many various sampling groups, into the Azerbaijani language. Another objective of the study is to determine the prevalence of Internet addiction among Azerbaijani adolescents and youth, which…

  1. The Turkish Version of Web-Based Learning Platform Evaluation Scale: Reliability and Validity Study

    ERIC Educational Resources Information Center

    Dag, Funda

    2016-01-01

    The purpose of this study is to determine the language equivalence and the validity and reliability of the Turkish version of the "Web-Based Learning Platform Evaluation Scale" ("Web Tabanli Ögrenme Ortami Degerlendirme Ölçegi" [WTÖODÖ]) used in the selection and evaluation of web-based learning environments. Within this scope,…

  2. Open and Distance Education Accreditation Standards Scale: Validity and Reliability Studies

    ERIC Educational Resources Information Center

    Can, Ertug

    2016-01-01

    The purpose of this study is to develop, and test the validity and reliability of a scale for the use of researchers to determine the accreditation standards of open and distance education based on the views of administrators, teachers, staff and students. This research was designed according to the general descriptive survey model since it aims…

  3. Developing a Science Process Skills Test for Secondary Students: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Feyzioglu, Burak; Demirdag, Baris; Akyildiz, Murat; Altun, Eralp

    2012-01-01

    Science process skills are claimed to enable an individual to improve their own life visions and give a scientific view/literacy as a standard of their understanding about the nature of science. The main purpose of this study was to develop a test for measuring a valid, reliable and practical test for Science Process Skills (SPS) in secondary…

  4. Bones, Boys, Bombs and Booze: An Exploratory Study of the Reliability of Marking Dissertations across Disciplines

    ERIC Educational Resources Information Center

    Bettany-Saltikov, Josette; Kilinc, Stephanie; Stow, Karen

    2009-01-01

    The primary aim of this study was to evaluate the reliability of the University's Masters' level (M-level) generic assessment criteria when used by lecturers from different disciplines. A further aim was to evaluate if subject-specific knowledge was essential to marking these dissertations. Four senior lecturers from diverse disciplines…

  5. Piagetian Formal Operational Tasks: A Crossover Study of Learning Effect and Reliability

    ERIC Educational Resources Information Center

    Lawson, Anton E.; And Others

    1974-01-01

    The general purposes of this study were to analyze responses on five Piagetian formal operational tasks in a test-retest situation to determine the extent to which taking a pretest effected scores on posttests and to determine task and examiner reliabilities. Significant test score gains on Piagetian tasks appeared to result from test-retest…

  6. Validity and Reliability of Turkish Version of Gilliam Autism Rating Scale-2: Results of Preliminary Study

    ERIC Educational Resources Information Center

    Diken, Ibrahim H.; Diken, Ozlem; Gilliam, James E.; Ardic, Avsar; Sweeney, Dwight

    2012-01-01

    The purpose of this preliminary study was to explore the validity and reliability of Turkish Version of the Gilliam Autism Rating Scale-2 (TV-GARS-2). Participants included 436 children diagnosed with autism (331 male and 105 female, mean of ages was 8.01 with SD = 3.77). Data were also collected from individuals diagnosed with intellectual…

  7. The Diagnostic Reading Test, Survey Section, Form E: A Reliability Study.

    ERIC Educational Resources Information Center

    Pellegrine, R. J.

    The Diagnostic Reading Tests were designed to assess the reading skills of college students enrolled in reading centers. To assess the reliability of the Diagnostic Reading Tests, Survey Section, Form E (DRTE), a study was conducted with university freshmen as subjects. The DRTE was administered to 31 students in an Educational Opportunity Program…

  8. The Reading Essential Skills Screener-Elementary Version (RESS-E): Studies of Reliability and Validity

    ERIC Educational Resources Information Center

    Erford, Bradley T.; Stephens, Vicki M.

    2005-01-01

    Technical characteristics of the Reading Essential Skills Screener-Elementary Version (RESS-E; B. T. Erford, G. Vitali, R. Haas, & R. R. Boykin, 1995) were studied using 4 independent samples of boys and girls between the ages of 6 and 8 years. Evidence of internal consistency, test-retest reliability, decision efficiency, factorial validity,…

  9. Reliability of an fMRI Paradigm for Emotional Processing in a Multisite Longitudinal Study

    PubMed Central

    Gee, Dylan G.; McEwen, Sarah C.; Forsyth, Jennifer K.; Haut, Kristen M.; Bearden, Carrie E.; Addington, Jean; Goodyear, Bradley; Cadenhead, Kristin S.; Mirzakhanian, Heline; Cornblatt, Barbara A.; Olvet, Doreen; Mathalon, Daniel H.; McGlashan, Thomas H.; Perkins, Diana O.; Belger, Aysenil; Seidman, Larry J.; Thermenos, Heidi; Tsuang, Ming T.; van Erp, Theo G.M.; Walker, Elaine F.; Hamann, Stephan; Woods, Scott W.; Constable, Todd; Cannon, Tyrone D.

    2015-01-01

    Multisite neuroimaging studies can facilitate the investigation of brain-related changes in many contexts, including patient groups that are relatively rare in the general population. Though multisite studies have characterized the reliability of brain activation during working memory and motor functional magnetic resonance imaging tasks, emotion processing tasks, pertinent to many clinical populations, remain less explored. A traveling participants study was conducted with eight healthy volunteers scanned twice on consecutive days at each of the eight North American Longitudinal Prodrome Study sites. Tests derived from generalizability theory showed excellent reliability in the amygdala (Eρ2=0.82), inferior frontal gyrus (IFG;Eρ2=0.83), anterior cingulate cortex (ACC;Eρ2=0.76), insula (Eρ2=0.85), and fusiform gyrus (Eρ2=0.91) for maximum activation and fair to excellent reliability in the amygdala (Eρ2=0.44), IFG (Eρ2=0.48), ACC (Eρ2=0.55), insula (Eρ2=0.42), and fusiform gyrus (Eρ2=0.83) for mean activation across sites and test days. For the amygdala, habituation (Eρ2=0.71) was more stable than mean activation. In a second investigation, data from 111 healthy individuals across sites were aggregated in a voxelwise, quantitative meta-analysis. When compared with a mixed effects model controlling for site, both approaches identified robust activation in regions consistent with expected results based on prior single-site research. Overall, regions central to emotion processing showed strong reliability in the traveling participants study and robust activation in the aggregation study. These results support the reliability of blood oxygen level-dependent signal in emotion processing areas across different sites and scanners and may inform future efforts to increase efficiency and enhance knowledge of rare conditions in the population through multisite neuroimaging paradigms. PMID:25821147

  10. Reliability of Health-Related Physical Fitness Tests among Colombian Children and Adolescents: The FUPRECOL Study.

    PubMed

    Ramírez-Vélez, Robinson; Rodrigues-Bezerra, Diogo; Correa-Bautista, Jorge Enrique; Izquierdo, Mikel; Lobelo, Felipe

    2015-01-01

    Substantial evidence indicates that youth physical fitness levels are an important marker of lifestyle and cardio-metabolic health profiles and predict future risk of chronic diseases. The reliability physical fitness tests have not been explored in Latino-American youth population. This study's aim was to examine the reliability of health-related physical fitness tests that were used in the Colombian health promotion "Fuprecol study". Participants were 229 Colombian youth (boys n = 124 and girls n = 105) aged 9 to 17.9 years old. Five components of health-related physical fitness were measured: 1) morphological component: height, weight, body mass index (BMI), waist circumference, triceps skinfold, subscapular skinfold, and body fat (%) via impedance; 2) musculoskeletal component: handgrip and standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) flexibility component (hamstring and lumbar extensibility, sit-and-reach test); 5) cardiorespiratory component: 20-meter shuttle-run test (SRT) to estimate maximal oxygen consumption. The tests were performed two times, 1 week apart on the same day of the week, except for the SRT which was performed only once. Intra-observer technical errors of measurement (TEMs) and inter-rater (reliability) were assessed in the morphological component. Reliability for the Musculoskeletal, motor and cardiorespiratory fitness components was examined using Bland-Altman tests. For the morphological component, TEMs were small and reliability was greater than 95% of all cases. For the musculoskeletal, motor, flexibility and cardiorespiratory components, we found adequate reliability patterns in terms of systematic errors (bias) and random error (95% limits of agreement). When the fitness assessments were performed twice, the systematic error was nearly 0 for all tests, except for the sit and reach (mean difference: -1.03% [95% CI = -4.35% to -2.28%]. The results from this study indicate that the "Fuprecol

  11. Standardised clients as assessors in a veterinary communication OSCE: a reliability and validity study.

    PubMed

    Artemiou, E; Adams, C L; Hecker, K G; Vallevand, A; Violato, C; Coe, J B

    2014-11-22

    In human medicine, standardised patients (SP) have been shown to reliably and accurately assess learners' communication performance in high-stakes certification Objective Structured Clinical Examinations (OSCE), offering a feasible way to reduce the need for recruitment, time commitment and coordination of faculty assessors. In this study, we evaluated the use of standardised clients (SC) as a viable option for assessing veterinary students' communication performance. We designed a four-station, two-track communication skills OSCE. SC assessors used an adapted nine-item Liverpool Undergraduate Communication Assessment Scale (LUCAS). Faculty used a 21-item checklist derived from the Calgary-Cambridge Guide (CCG) and a five-point global rating scale. Participants were second year veterinary students (n=96). For the four stations, intrastation reliability (α) ranged from 0.63 to 0.82 for the LUCAS, and 0.73 to 0.87 for the CCG. The interstation reliability coefficients were 0.85 for the LUCAS and 0.89 for the CGG. The calculated Generalisability (G) coefficients were 0.62 for the LUCAS and 0.60 for the CGG. Supporting construct validity, SC and faculty assessors showed a significant correlation between the LUCAS and CCG total percent scores (r=0.45, P<0.001), and likewise between the LUCAS and global rating scores (r=0.49, P<0.001).Study results support that SC assessors offer a reliable and valid approach for assessing veterinary communication OSCE.

  12. Reliability Generalization: "Lapsus Linguae"

    ERIC Educational Resources Information Center

    Smith, Julie M.

    2011-01-01

    This study examines the proposed Reliability Generalization (RG) method for studying reliability. RG employs the application of meta-analytic techniques similar to those used in validity generalization studies to examine reliability coefficients. This study explains why RG does not provide a proper research method for the study of reliability,…

  13. 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.

  14. Study for Reliability Assessment considering the Sedimentation in Urban Sewer Networks

    NASA Astrophysics Data System (ADS)

    Song, Yangho; Park, Moojong; Lee, Jungho

    2016-04-01

    In this study, analysis of reliability of sewer network was progressed with the number of overflow nodes and overflow volume simultaneously for urban areas considering sedimentation. Reliability analysis shows that it is possible to quantify the difference in the phenomenon of the destruction of sedimentation in urban sewer system under the same design frequency. This study focuses on the release to bed of sedimentations having being accumulated inside a urban sewer network. It is proposed as one of the indicators evaluated as full reliability for sewer system. To analyze detailed changes in conduit designs in urban sewer networks, tried to reduction of sedimentation in sewer networks using modified pipe slope in Bujeon-dong catchment, Busan. The various sewer designs were applied and then, the most effective improvement of reliability over 10%. Suggested reliability process can produce the quantitative evaluations about sewer systems using the results of the system simulations and use of possible the objective function for the sewer network designed with a relative evaluation. Sewer network is designed to pass the inflow rate depending on the design frequency smoothly. However, taking a look at the example of flooding generated in urban area shows that an increase in the generation and damage of flooding can be often caused by the deposition of sediment in the sewer. This is a problem in the maintenance of sewers, but this implies that the effect of sediment deposition should be considered to some degree for the design of a conduit itself in another aspect. Thus, it is necessary to realize design in a direction to reduce flood damage pursuant to it by considering the deposition aspect of sediment in a conduit when designing a storm sewer.

  15. Intra and inter-rater reliability study of pelvic floor muscle dynamometric measurements

    PubMed Central

    Martinho, Natalia M.; Marques, Joseane; Silva, Valéria R.; Silva, Silvia L. A.; Carvalho, Leonardo C.; Botelho, Simone

    2015-01-01

    OBJECTIVE: The aim of this study was to evaluate the intra and inter-rater reliability of pelvic floor muscle (PFM) dynamometric measurements for maximum and average strengths, as well as endurance. METHOD: A convenience sample of 18 nulliparous women, without any urogynecological complaints, aged between 19 and 31 (mean age of 25.4±3.9) participated in this study. They were evaluated using a pelvic floor dynamometer based on load cell technology. The dynamometric evaluations were repeated in three successive sessions: two on the same day with a rest period of 30 minutes between them, and the third on the following day. All participants were evaluated twice in each session; first by examiner 1 followed by examiner 2. The vaginal dynamometry data were analyzed using three parameters: maximum strength, average strength, and endurance. The Intraclass Correlation Coefficient (ICC) was applied to estimate the PFM dynamometric measurement reliability, considering a good level as being above 0.75. RESULTS: The intra and inter-raters' analyses showed good reliability for maximum strength (ICCintra-rater1=0.96, ICCintra-rater2=0.95, and ICCinter-rater=0.96), average strength (ICCintra-rater1=0.96, ICCintra-rater2=0.94, and ICCinter-rater=0.97), and endurance (ICCintra-rater1=0.88, ICCintra-rater2=0.86, and ICCinter-rater=0.92) dynamometric measurements. CONCLUSIONS: The PFM dynamometric measurements showed good intra- and inter-rater reliability for maximum strength, average strength and endurance, which demonstrates that this is a reliable device that can be used in clinical practice. PMID:25993624

  16. Reliable Crack Detection in Turbine Blades Using Thermosonics: AN Empirical Study

    NASA Astrophysics Data System (ADS)

    Bolu, G.; Gachagan, A.; Pierce, G.; Harvey, G.

    2010-02-01

    Excitation generated by ultrasonic horns typically used in thermosonics (or Sonic IR) is non-reproducible, raising concerns that cracks in some locations can be missed. This paper presents an empirical study on the thermosonic inspection of turbine blades. The objective is to assess the reliability of thermosonics as an NDT screening method for findings crack in turbine blades. First, a study was carried out to establish the operating parameters that generated the highest possible temperature rise from a crack. Next, a repeatability study was conducted to measure consistency of results in 300 tests, which showed 100% repeatability. Finally, 60 cracked blades were inspected, with the known cracks in 57 blades detected. These results show the potential of thermosonics as a reliable NDT screening method for finding cracks in turbine blades.

  17. Measurement of hyoid and laryngeal displacement in video fluoroscopic swallowing studies: variability, reliability, and measurement error.

    PubMed

    Sia, Isaac; Carvajal, Pamela; Carnaby-Mann, Giselle D; Crary, Michael A

    2012-06-01

    Video fluoroscopy is commonly used in the study of swallowing kinematics. However, various procedures used in linear measurements obtained from video fluoroscopy may contribute to increased variability or measurement error. This study evaluated the influence of calibration referent and image rotation on measurement variability for hyoid and laryngeal displacement during swallowing. Inter- and intrarater reliabilities were also estimated for hyoid and laryngeal displacement measurements across conditions. The use of different calibration referents did not contribute significantly to variability in measures of hyoid and laryngeal displacement but image rotation affected horizontal measures for both structures. Inter- and intrarater reliabilities were high. Using the 95% confidence interval as the error index, measurement error was estimated to range from 2.48 to 3.06 mm. These results address procedural decisions for measuring hyoid and laryngeal displacement in video fluoroscopic swallowing studies.

  18. Reliability of Health-Related Physical Fitness Tests among Colombian Children and Adolescents: The FUPRECOL Study

    PubMed Central

    Ramírez-Vélez, Robinson; Rodrigues-Bezerra, Diogo; Correa-Bautista, Jorge Enrique; Izquierdo, Mikel; Lobelo, Felipe

    2015-01-01

    Substantial evidence indicates that youth physical fitness levels are an important marker of lifestyle and cardio-metabolic health profiles and predict future risk of chronic diseases. The reliability physical fitness tests have not been explored in Latino-American youth population. This study’s aim was to examine the reliability of health-related physical fitness tests that were used in the Colombian health promotion “Fuprecol study”. Participants were 229 Colombian youth (boys n = 124 and girls n = 105) aged 9 to 17.9 years old. Five components of health-related physical fitness were measured: 1) morphological component: height, weight, body mass index (BMI), waist circumference, triceps skinfold, subscapular skinfold, and body fat (%) via impedance; 2) musculoskeletal component: handgrip and standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) flexibility component (hamstring and lumbar extensibility, sit-and-reach test); 5) cardiorespiratory component: 20-meter shuttle-run test (SRT) to estimate maximal oxygen consumption. The tests were performed two times, 1 week apart on the same day of the week, except for the SRT which was performed only once. Intra-observer technical errors of measurement (TEMs) and inter-rater (reliability) were assessed in the morphological component. Reliability for the Musculoskeletal, motor and cardiorespiratory fitness components was examined using Bland–Altman tests. For the morphological component, TEMs were small and reliability was greater than 95% of all cases. For the musculoskeletal, motor, flexibility and cardiorespiratory components, we found adequate reliability patterns in terms of systematic errors (bias) and random error (95% limits of agreement). When the fitness assessments were performed twice, the systematic error was nearly 0 for all tests, except for the sit and reach (mean difference: -1.03% [95% CI = -4.35% to -2.28%]. The results from this study indicate that the

  19. Test-retest reliability of white matter structural brain networks: a multiband diffusion MRI study.

    PubMed

    Zhao, Tengda; Duan, Fei; Liao, Xuhong; Dai, Zhengjia; Cao, Miao; He, Yong; Shu, Ni

    2015-01-01

    The multiband EPI sequence has been developed for the human connectome project to accelerate MRI data acquisition. However, no study has yet investigated the test-retest (TRT) reliability of the graph metrics of white matter (WM) structural brain networks constructed from this new sequence. Here, we employed a multiband diffusion MRI (dMRI) dataset with repeated scanning sessions and constructed both low- and high-resolution WM networks by volume- and surface-based parcellation methods. The reproducibility of network metrics and its dependence on type of construction procedures was assessed by the intra-class correlation coefficient (ICC). We observed conserved topological architecture of WM structural networks constructed from the multiband dMRI data as previous findings from conventional dMRI. For the global network properties, the first order metrics were more reliable than second order metrics. Between two parcellation methods, networks with volume-based parcellation showed better reliability than surface-based parcellation, especially for the global metrics. Between different resolutions, the high-resolution network exhibited higher TRT performance than the low-resolution in terms of the global metrics with a large effect size, whereas the low-resolution performs better in terms of local (region and connection) properties with a relatively low effect size. Moreover, we identified that the association and primary cortices showed higher reproducibility than the paralimbic/limbic regions. The important hub regions and rich-club connections are more reliable than the non-hub regions and connections. Finally, we found WM networks from the multiband dMRI showed higher reproducibility compared with those from the conventional dMRI. Together, our results demonstrated the fair to good reliability of the WM structural brain networks from the multiband EPI sequence, suggesting its potential utility for exploring individual differences and for clinical applications.

  20. Ultrasound assessment for grading structural tendon changes in supraspinatus tendinopathy: an inter-rater reliability study

    PubMed Central

    Hjarbaek, John; Eshoej, Henrik; Larsen, Camilla Marie; Vobbe, Jette; Juul-Kristensen, Birgit

    2016-01-01

    Aim To evaluate the inter-rater reliability of measuring structural changes in the tendon of patients, clinically diagnosed with supraspinatus tendinopathy (cases) and healthy participants (controls), on ultrasound (US) images captured by standardised procedures. Methods A total of 40 participants (24 patients) were included for assessing inter-rater reliability of measurements of fibrillar disruption, neovascularity, as well as the number and total length of calcifications and tendon thickness. Linear weighted κ, intraclass correlation (ICC), SEM, limits of agreement (LOA) and minimal detectable change (MDC) were used to evaluate reliability. Results ‘Moderate—almost perfect’ κ was found for grading fibrillar disruption, neovascularity and number of calcifications (k 0.60–0.96). For total length of calcifications and tendon thickness, ICC was ‘excellent’ (0.85–0.90), with SEM(Agreement) ranging from 0.63 to 2.94 mm and MDC(group) ranging from 0.28 to 1.29 mm. In general, SEM, LOA and MDC showed larger variation for calcifications than for tendon thickness. Conclusions Inter-rater reliability was moderate to almost perfect when a standardised procedure was applied for measuring structural changes on captured US images and movie sequences of relevance for patients with supraspinatus tendinopathy. Future studies should test intra-rater and inter-rater reliability of the method in vivo for use in clinical practice, in addition to validation against a gold standard, such as MRI. Trial registration number NCT01984203; Pre-results. PMID:27221128

  1. Reliability study: raw and make-up water system, Portsmouth Gaseous Diffusion Plant

    SciTech Connect

    Peterman, S.M.; Wiehle, W.E.; Walder, A.; Houk, T.C.; West, R.M.

    1981-09-01

    A reliability study for determining the ability of the raw and make-up water system to provide reliable and adequate service through the year 2000 has been completed. This study includes an evaluation of the well fields, X-608 Raw Water Pump House, X-605 Booster Station Complex, X-611 Water Treatment Complex, and the associated piping. The raw and make-up water system is in good overall condition, but to maintain this condition, the reliability study team made the following recommendations: (1) increase well field capacity; (2) replace certain speed reducers at X-611; (3) repair deteriorated poles, crossarms, and accessories on F-2 and W-1 feeders; (4) stabilize the landslide in vicinity of the 48 in. raw water main; and (5) initiate further investigation, testing, or engineering studies to correct deficiencies in the supervisory control system between well fields, pump house, and X-611, determine if the 2400 volt underground cables to X-608A wells should be replaced.

  2. Optimal sample sizes for the design of reliability studies: power consideration.

    PubMed

    Shieh, Gwowen

    2014-09-01

    Intraclass correlation coefficients are used extensively to measure the reliability or degree of resemblance among group members in multilevel research. This study concerns the problem of the necessary sample size to ensure adequate statistical power for hypothesis tests concerning the intraclass correlation coefficient in the one-way random-effects model. In view of the incomplete and problematic numerical results in the literature, the approximate sample size formula constructed from Fisher's transformation is reevaluated and compared with an exact approach across a wide range of model configurations. These comprehensive examinations showed that the Fisher transformation method is appropriate only under limited circumstances, and therefore it is not recommended as a general method in practice. For advance design planning of reliability studies, the exact sample size procedures are fully described and illustrated for various allocation and cost schemes. Corresponding computer programs are also developed to implement the suggested algorithms.

  3. A reliability generalization study of coefficient alpha for the UCLA loneliness scale.

    PubMed

    Vassar, Matt; Crosby, James W

    2008-11-01

    Loneliness is a psychological construct that has been reported in a variety of populations and associated with a number of other negative psychological problems. This study was an examination of coefficient alpha of a prominent measure of loneliness: the University of California, Los Angeles (UCLA) Loneliness Scale (Russell, Peplau, & Cutrona, 1980; Russell, 1996). We utilized reliability generalization to provide an aggregate estimate of the reliability of the scale over time and in a variety of populations as well as to assess and identify sampling and demographic characteristics associated with variability in coefficient alpha. Of the 213 studies examined, 80 had reported alpha estimates, and we used them in this analysis. We discuss conditions associated with variability in coefficient alpha along with pertinent implications for practice and future research.

  4. EEG interpretation reliability and interpreter confidence: a large single-center study.

    PubMed

    Grant, Arthur C; Abdel-Baki, Samah G; Weedon, Jeremy; Arnedo, Vanessa; Chari, Geetha; Koziorynska, Ewa; Lushbough, Catherine; Maus, Douglas; McSween, Tresa; Mortati, Katherine A; Reznikov, Alexandra; Omurtag, Ahmet

    2014-03-01

    The intrarater and interrater reliability (I&IR) of EEG interpretation has significant implications for the value of EEG as a diagnostic tool. We measured both the intrarater reliability and the interrater reliability of EEG interpretation based on the interpretation of complete EEGs into standard diagnostic categories and rater confidence in their interpretations and investigated sources of variance in EEG interpretations. During two distinct time intervals, six board-certified clinical neurophysiologists classified 300 EEGs into one or more of seven diagnostic categories and assigned a subjective confidence to their interpretations. Each EEG was read by three readers. Each reader interpreted 150 unique studies, and 50 studies were re-interpreted to generate intrarater data. A generalizability study assessed the contribution of subjects, readers, and the interaction between subjects and readers to interpretation variance. Five of the six readers had a median confidence of ≥99%, and the upper quartile of confidence values was 100% for all six readers. Intrarater Cohen's kappa (κc) ranged from 0.33 to 0.73 with an aggregated value of 0.59. Cohen's kappa ranged from 0.29 to 0.62 for the 15 reader pairs, with an aggregated Fleiss kappa of 0.44 for interrater agreement. Cohen's kappa was not significantly different across rater pairs (chi-square=17.3, df=14, p=0.24). Variance due to subjects (i.e., EEGs) was 65.3%, due to readers was 3.9%, and due to the interaction between readers and subjects was 30.8%. Experienced epileptologists have very high confidence in their EEG interpretations and low to moderate I&IR, a common paradox in clinical medicine. A necessary, but insufficient, condition to improve EEG interpretation accuracy is to increase intrarater and interrater reliability. This goal could be accomplished, for instance, with an automated online application integrated into a continuing medical education module that measures and reports EEG I&IR to individual

  5. A nine-test screening battery for athletes: a reliability study.

    PubMed

    Frohm, A; Heijne, A; Kowalski, J; Svensson, P; Myklebust, G

    2012-06-01

    Studies have shown that reduced neuromuscular control or strength increases the risk of acute injuries. It is hypothesized that a non-functional movement pattern can predispose for injuries. In the present paper a detailed description of a test battery consisting of nine different tests to screen athletic movement pattern is provided. The aim was to evaluate the inter- and intra-rater reliability of the test battery on a group of male elite soccer players. Twenty-six healthy elite soccer players (17-28 years) were screened. Eighteen participated at a second occasion 7 days later. No significant difference (P=0.31) was found between test occasion 1 (LS means 18.3, 95% confidence interval 14.9-21.7) and test occasion 2 (18.0, 14.4-21.7) in the mean total score of the test battery. No significant difference in the inter-rater reliability was found between the eight physiotherapists at the two test occasions. The intra-class correlation coefficient was 0.80 and 0.81, respectively. The test battery showed good inter- and intra-rater reliability. The screening battery is easy to use for familiarized professionals and requires minimal equipment. However, further studies are needed to confirm the validity of the test battery in injury prevention, rehabilitation and performance enhancement.

  6. Reliability physics

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.; Ross, R. G., Jr.

    1984-01-01

    Speakers whose topics relate to the reliability physics of solar arrays are listed and their topics briefly reviewed. Nine reports are reviewed ranging in subjects from studies of photothermal degradation in encapsulants and polymerizable ultraviolet stabilizers to interface bonding stability to electrochemical degradation of photovoltaic modules.

  7. Reliability and validity of mobile teledermatology in HIV positive patients in Botswana: a pilot study

    PubMed Central

    Azfar, Rahat S; Lee, Robert A.; Castelo-Soccio, Leslie; Greenberg, Martin S.; Bilker, Warren B; Gelfand, Joel M; Kovarik, Carrie L

    2014-01-01

    Importance Mobile teledermatology may increase access to care. Objective To determine if mobile teledermatology in HIV positive patients in Gaborone, Botswana was reliable and produced valid consultations in comparison to face-to-face dermatology consultations. Design Cross-sectional study Setting Outpatient clinics and public inpatient settings in Botswana. Participants 76 HIV positive patients aged 18 years and up with a skin or mucosal complaint that had not been previously evaluated by a dermatologist. Main Outcome(s) and Measure(s) We calculated Cohen's kappa coefficient for diagnosis, diagnostic category and management for test-retest reliability and for inter-rater reliability. We also calculated sensitivity and specificity for each diagnosis. Results Cohen's kappa for test-retest reliability ranged from 0.47 (95% CI 0.35-0.59) to 0.78 (95% CI 0.67-0.88) for the primary diagnosis, 0.29 (95% CI 0.18-0.42) to 0.73 (95% CI 0.61-0.84) for diagnostic category, and 0.17 (95% CI -0.01-0.36) to 0.54 (95% CI 0.38-0.70) for management. Cohen's kappa for inter-rater reliability ranged from 0.41 (95% CI 0.31-0.52) to 0.51 (95% CI 0.41-0.61) for the primary diagnosis, from 0.22 (95% CI 0.14-0.31) to 0.43 (95% CI 0.34-0.53) for the diagnostic category for the primary diagnosis and from 0.08 (95% CI 0.02-0.15) to 0.12 (95% CI 0.01-0.23) for management. Sensitivity and specificity for the top ten diagnoses ranged from 0 to 0.88 and from 0.84 to 1 respectively. Conclusions and Relevance Our results suggest that while the use of mobile teledermatology technology in HIV-positive patients in Botswana has significant potential for improving access to care, additional work is needed to improve reliability and validity of this technology on a larger scale in this population. PMID:24622778

  8. Alternatives for Mixed-Effects Meta-Regression Models in the Reliability Generalization Approach: A Simulation Study

    ERIC Educational Resources Information Center

    López-López, José Antonio; Botella, Juan; Sánchez-Meca, Julio; Marín-Martínez, Fulgencio

    2013-01-01

    Since heterogeneity between reliability coefficients is usually found in reliability generalization studies, moderator analyses constitute a crucial step for that meta-analytic approach. In this study, different procedures for conducting mixed-effects meta-regression analyses were compared. Specifically, four transformation methods for the…

  9. Reliability of on-site greywater treatment systems in Mediterranean and arid environments - a case study.

    PubMed

    Alfiya, Y; Gross, A; Sklarz, M; Friedler, E

    2013-01-01

    On-site greywater (GW) treatment and reuse is gaining popularity. However, a main point of concern is that inadequate treatment of such water may lead to negative environmental and health effects. Maintenance of single-family home GW systems is usually performed by home owners with limited professional support. Therefore, unless GW systems are reliable, environmental and public health might be compromised. This study is aimed at investigating the reliability of on-site recirculated vertical flow constructed wetlands (RVFCW) in 20 single-family homes. In order to ensure reliability, the failure-tree approach was adopted during the design and construction of the systems. The performance of the systems was monitored for 1.5 years, by evaluating treated GW flow and quality, and by recording all malfunctions and maintenance work. Only 39 failures occurred during this period, of which four caused irrigation with impaired quality GW, while the rest led to no irrigation. The mean time between failures (MTBF) was 305 days; two out of the 20 systems suffered from seven malfunctions (each), while nine systems did not fail at all. Thus, it can be postulated that if on-site GW treatment systems are designed with the right controls, and if scheduled (basic and relatively infrequent) maintenance is performed, GW reuse can be safe to the environment and human health.

  10. Reliability of mandibular canine and mandibular canine index in sex determination: A study using Uyghur population.

    PubMed

    Iqbal, Raza; Zhang, Shuang; Mi, Congbo

    2015-07-01

    Sex determination is a key process that is required to establish the forensic profile of an individual. Mandibular canine index (MCI) method yields fairly positive results for sex determination. However, this method has been challenged by a few authors. This study aimed to examine the reliability of MCI in Chinese Uyghur population and to establish its normal value for this ethnic group. Dental casts of 216 students (117 males and 119 females) from the College of Stomatology of Xinjiang Medical University in China were used to determine the sexing accuracy of MCI. The mesiodistal (MD) dimension of mandibular canine crowns, the inter-canine distance, and the MCI were calculated. The accuracy of the standard MCI derived from the current data was compared with that of the standard MCIs derived from previous data. Results were statistically described using the independent-samples t-test. The MD dimension of mandibular crown, the inter-canine distance, and the MCI exhibited statistically significant sexual dimorphism. Sex determination using the MCI derived from the current data revealed fairly reliable results. Therefore, MCI is a reliable method for sex determination for Uyghur population, with 0.248 as standard MCI value.

  11. A Longitudinal Study of the Reliability of Acupuncture Deqi Sensations in Knee Osteoarthritis

    PubMed Central

    Spaeth, Rosa B.; Camhi, Stephanie; Hashmi, Javeria A.; Vangel, Mark; Wasan, Ajay D.; Edwards, Robert R.; Gollub, Randy L.; Kong, Jian

    2013-01-01

    Deqi is one of the core concepts in acupuncture theory and encompasses a range of sensations. In this study, we used the MGH Acupuncture Sensation Scale (MASS) to measure and assess the reliability of the sensations evoked by acupuncture needle stimulation in a longitudinal clinical trial on knee osteoarthritis (OA) patients. The Knee injury and Osteoarthritis Outcome Score (KOOS) was used as the clinical outcome. Thirty OA patients were randomized into one of three groups (high dose, low dose, and sham acupuncture) for 4 weeks. We found that, compared with sham acupuncture, real acupuncture (combining high and low doses) produced significant improvement in knee pain (P = .025) and function in sport (P = .049). Intraclass correlation analysis showed that patients reliably rated 11 of the 12 acupuncture sensations listed on the MASS and that heaviness was rated most consistently. Overall perceived sensation (MASS Index) (P = .014), ratings of soreness (P = .002), and aching (P = .002) differed significantly across acupuncture groups. Compared to sham acupuncture, real acupuncture reliably evoked stronger deqi sensations and led to better clinical outcomes when measured in a chronic pain population. Our findings highlight the MASS as a useful tool for measuring deqi in acupuncture research. PMID:23935656

  12. The Test–Retest Reliability of the Form 90-DWI: An Instrument for Assessing Intoxicated Driving

    PubMed Central

    Hettema, Jennifer E.; Miller, William R.; Tonigan, J. Scott; Delaney, Harold D.

    2010-01-01

    Although driving while intoxicated (DWI) is a pervasive problem, reliable measures of this behavior have been elusive. In the present study, the Form 90, a widely utilized alcohol and substance use instrument, was adapted for measurement of DWI and related behaviors. Levels of reliability for the adapted instrument, the Form 90-DWI, were tested among a university sample of 60 undergraduate students who had consumed alcohol during the past 90 days. The authors administered the instrument once during an intake interview and again, 7–30 days later, to determine levels of test–retest reliability. Overall, the Form 90-DWI demonstrated high levels of reliability for many general drinking and DWI behaviors. Levels of reliability were lower for riding with an intoxicated driver and for variables involving several behavioral conjunctions, such as seat belt use and the presence of passengers when driving with a blood alcohol concentration above .08. Overall, the Form 90-DWI shows promise as a reliable measure of DWI behavior in research on treatment outcome and prevention. PMID:18298237

  13. Reliability and Validity Study of Clinical Ultrasound Imaging on Lateral Curvature of Adolescent Idiopathic Scoliosis

    PubMed Central

    Wang, Q.; Li, M.; Lou, Edmond H. M.; Wong, M. S.

    2015-01-01

    Background Non-ionizing radiation imaging assessment has been advocated for the patients with adolescent idiopathic scoliosis (AIS). As one of the radiation-free methods, ultrasound imaging has gained growing attention in scoliosis assessment over the past decade. The center of laminae (COL) method has been proposed to measure the spinal curvature in the coronal plane of ultrasound image. However, the reliability and validity of this ultrasound method have not been validated in the clinical setting. Objectives To evaluate the reliability and validity of clinical ultrasound imaging on lateral curvature measurements of AIS with their corresponding magnetic resonance imaging (MRI) measurements. Methods Thirty curves (ranged 10.2°–68.2°) from sixteen patients with AIS were eligible for this study. The ultrasound scan was performed using a 3-D ultrasound unit within the same morning of MRI examination. Two researchers were involved in data collection of these two examinations. The COL method was used to measure the coronal curvature in ultrasound image, compared with the Cobb method in MRI. The intra- and inter-rater reliability of the COL method was evaluated by intra-class correlation coefficient (ICC). The validity of this method was analyzed by paired Student’s t-test, Bland–Altman statistics and Pearson correlation coefficient. The level of significance was set as 0.05. Results The COL method showed high intra- and inter-rater reliabilities (both with ICC (2, K) >0.9, p<0.05) to measure the coronal curvature. Compared with Cobb method, COL method showed no significant difference (p<0.05) when measuring coronal curvature. Furthermore, Bland-Altman method demonstrated an agreement between these two methods, and Pearson’s correlation coefficient (r) was high (r>0.9, p<0.05). Conclusion The ultrasound imaging could provide a reliable and valid measurement of spinal curvature in the coronal plane using the COL method. Further research is needed to validate the

  14. A Reliability and Validity of an Instrument to Evaluate the School-Based Assessment System: A Pilot Study

    ERIC Educational Resources Information Center

    Ghazali, Nor Hasnida Md

    2016-01-01

    A valid, reliable and practical instrument is needed to evaluate the implementation of the school-based assessment (SBA) system. The aim of this study is to develop and assess the validity and reliability of an instrument to measure the perception of teachers towards the SBA implementation in schools. The instrument is developed based on a…

  15. What Are the Consequences if the Assumption of Independent Observations Is Violated in Reliability Generalization Meta-Analysis Studies?

    ERIC Educational Resources Information Center

    Romano, Jeanine L.; Kromrey, Jeffrey D.

    2009-01-01

    This study was conducted to evaluate alternative analysis strategies for the meta-analysis method of reliability generalization when the reliability estimates are not statistically independent. Five approaches to dealing with the violation of independence were implemented: ignoring the violation and treating each observation as independent,…

  16. An Investigation of the Reliability of the Rosenzweig Picture-Frustration (P-F) Study, Children's Form.

    ERIC Educational Resources Information Center

    Rosenzweig, Saul

    1978-01-01

    Data are presented on the retest and split-half reliability of the Rosenzweig Picture-Frustration (P-F) Study, Children's Form, for two groups of subjects (aged 10-11 and 12-13), each group tested twice at an interval of three months. Reliability by retest was consistently higher than by the split-half method. (Author/CTM)

  17. [The Cambridge Mental Disorders of the Elderly Examination. Study of interobserver reliability].

    PubMed

    Llinàs, J; Vilalta, J; López Pousa, S; Vidal, C; Amiel, J

    1990-04-01

    Three teams formed by psychologists with experience in the administration of structured interviews evaluated by the CAMDEX (The Cambridge Mental Disorders of the Elderly Examination) in a sample of 41 patients for the interrater reliability study. While a psychologist interview patient, the other one observes each patient. The CAMDEX were completed independently by each of the examiners. The results demonstrate an elevated level agreement both for the different scales (p less than 0.001) and for the different diagnostic criteria employed by the CAMDEX (kappa = 0.88 for the DSM-III-R and Kappa = 1 for the ICD-10).

  18. Effect of formal specifications on program complexity and reliability: An experimental study

    NASA Technical Reports Server (NTRS)

    Goel, Amrit L.; Sahoo, Swarupa N.

    1990-01-01

    The results are presented of an experimental study undertaken to assess the improvement in program quality by using formal specifications. Specifications in the Z notation were developed for a simple but realistic antimissile system. These specifications were then used to develop 2 versions in C by 2 programmers. Another set of 3 versions in Ada were independently developed from informal specifications in English. A comparison of the reliability and complexity of the resulting programs suggests the advantages of using formal specifications in terms of number of errors detected and fault avoidance.

  19. The modified patient enablement instrument: a Portuguese cross-cultural adaptation, validity and reliability study.

    PubMed

    Remelhe, Mafalda; Teixeira, Pedro M; Lopes, Irene; Silva, Luís; Correia de Sousa, Jaime

    2017-01-12

    Enabling patients with asthma to obtain the knowledge, confidence and skills they need in order to assume a major role in the management of their disease is cost effective. It should be an integral part of any plan for long-term control of asthma. The modified Patient Enablement Instrument (mPEI) is an easily administered questionnaire that was adapted in the United Kingdom to measure patient enablement in asthma, but its applicability in Portugal is not known. Validity and reliability of questionnaires should be tested before use in settings different from those of the original version. The purpose of this study was to test the applicability of the mPEI to Portuguese asthma patients after translation and cross-cultural adaptation, and to verify the structural validity, internal consistency and reproducibility of the instrument. The mPEI was translated to Portuguese and back translated to English. Its content validity was assessed by a debriefing interview with 10 asthma patients. The translated instrument was then administered to a random sample of 142 patients with persistent asthma. Structural validity and internal consistency were assessed. For reproducibility analysis, 86 patients completed the instrument again 7 days later. Item-scale correlations and exploratory factor analysis were used to assess structural validity. Cronbach's alpha was used to test internal consistency, and the intra-class correlation coefficient was used for the analysis of reproducibility. All items of the Portuguese version of the mPEI were found to be equivalent to the original English version. There were strong item-scale correlations that confirmed construct validity, with a one component structure and good internal consistency (Cronbach's alpha >0.8) as well as high test-retest reliability (ICC=0.85). The mPEI showed sound psychometric properties for the evaluation of enablement in patients with asthma making it a reliable instrument for use in research and clinical practice in

  20. Quantifying the reliability of image replication studies: the image intraclass correlation coefficient (I2C2).

    PubMed

    Shou, H; Eloyan, A; Lee, S; Zipunnikov, V; Crainiceanu, A N; Nebel, N B; Caffo, B; Lindquist, M A; Crainiceanu, C M

    2013-12-01

    This article proposes the image intraclass correlation (I2C2) coefficient as a global measure of reliability for imaging studies. The I2C2 generalizes the classic intraclass correlation (ICC) coefficient to the case when the data of interest are images, thereby providing a measure that is both intuitive and convenient. Drawing a connection with classical measurement error models for replication experiments, the I2C2 can be computed quickly, even in high-dimensional imaging studies. A nonparametric bootstrap procedure is introduced to quantify the variability of the I2C2 estimator. Furthermore, a Monte Carlo permutation is utilized to test reproducibility versus a zero I2C2, representing complete lack of reproducibility. Methodologies are applied to three replication studies arising from different brain imaging modalities and settings: regional analysis of volumes in normalized space imaging for characterizing brain morphology, seed-voxel brain activation maps based on resting-state functional magnetic resonance imaging (fMRI), and fractional anisotropy in an area surrounding the corpus callosum via diffusion tensor imaging. Notably, resting-state fMRI brain activation maps are found to have low reliability, ranging from .2 to .4. Software and data are available to provide easy access to the proposed methods.

  1. Reliability of team-based self-monitoring in critical events: a pilot study

    PubMed Central

    2013-01-01

    Background Teamwork is a critical component during critical events. Assessment is mandatory for remediation and to target training programmes for observed performance gaps. Methods The primary purpose was to test the feasibility of team-based self-monitoring of crisis resource management with a validated teamwork assessment tool. A secondary purpose was to assess item-specific reliability and content validity in order to develop a modified context-optimised assessment tool. We conducted a prospective, single-centre study to assess team-based self-monitoring of teamwork after in-situ inter-professional simulated critical events by comparison with an assessment by observers. The Mayo High Performance Teamwork Scale (MHPTS) was used as the assessment tool with evaluation of internal consistency, item-specific consensus estimates for agreement between participating teams and observers, and content validity. Results 105 participants and 58 observers completed the MHPTS after a total of 16 simulated critical events over 8 months. Summative internal consistency of the MHPTS calculated as Cronbach’s alpha was acceptable with 0.712 for observers and 0.710 for participants. Overall consensus estimates for dichotomous data (agreement/non-agreement) was 0.62 (Cohen’s kappa; IQ-range 0.31-0.87). 6/16 items had excellent (kappa > 0.8) and 3/16 good reliability (kappa > 0.6). Short questions concerning easy to observe behaviours were more likely to be reliable. The MHPTS was modified using a threshold for good reliability of kappa > 0.6. The result is a 9 item self-assessment tool (TeamMonitor) with a calculated median kappa of 0.86 (IQ-range: 0.67-1.0) and good content validity. Conclusions Team-based self-monitoring with the MHPTS to assess team performance during simulated critical events is feasible. A context-based modification of the tool is achievable with good internal consistency and content validity. Further studies are needed to investigate if team

  2. Reliability of the step phase detection using inertial measurement units: pilot study.

    PubMed

    Sessa, Salvatore; Zecca, Massimiliano; Bartolomeo, Luca; Takashima, Takamichi; Fujimoto, Hiroshi; Takanishi, Atsuo

    2015-04-01

    The use of inertial sensors for the gait event detection during a long-distance walking, for example, on different surfaces and with different walking patterns, is important to evaluate the human locomotion. Previous studies demonstrated that gyroscopes on the shank or foot are more reliable than accelerometers and magnetometers for the event detection in case of normal walking. However, these studies did not link the events with the temporal parameters used in the clinical practice; furthermore, they did not clearly verify the optimal position for the sensors depending on walking patterns and surface conditions. The event detection quality of the sensors is compared with video, used as ground truth, according to the parameters proposed by the Gait and Clinical Movement Analysis Society. Additionally, the performance of the sensor on the foot is compared with the one on the shank. The comparison is performed considering both normal walking and deviations to the walking pattern, on different ground surfaces and with or without constraints on movements. The preliminary results show that the proposed methodology allows reliable detection of gait events, even in case of abnormal footfall and in slipping surface conditions, and that the optimal location to place the sensors is the shank.

  3. Grading Osteoarthritic Changes of the Zygapophyseal Joints from Radiographs: A Reliability Study

    PubMed Central

    Little, Joshua W.; Grieve, Thomas J.; Cramer, Gregory D.; Rich, Jeffrey A.; Laptook, Evelyn E.; Stiefel, Joseph P.D.; Linaker, Kathleen

    2015-01-01

    Objective This study tested the reliability of a 5-point ordinal scale used to grade the severity of degenerative changes of zygapophyseal (Z) joints on standard radiographs. Methods Modifications were made to Kellgren’s grading system to improve agreement for grading the severity of osteoarthritic changes in lumbar Z joints. These included adding 1 grade of no degeneration, multiple radiographic views, and structured examiner training. Thirty packets of radiographic files were obtained, which included representation of all 5 grades including no degeneration (0) and Kellgren’s 4-point (1 to 4) joint degeneration classification criteria. Radiographs were digitized to create a radiographic atlas that was given to examiners for individual study and blinded evaluation sessions. Intra-rater and inter-rater agreement was determined by weighted kappa (κw) from the examination of 79 Z joints (25 packets). Results Using the modified scale and following training, examiners demonstrated a moderate to substantial level of inter-rater agreement (κw = 0.57, 0.60, and 0.68). Intra-rater agreement was moderate (κw = 0.42 and 0.54). Conclusions The modified Kellgren 5-point grading system provides acceptable intra- and inter-rater reliability when examiners are adequately trained. This grading system may be a useful method for future investigations assessing radiographic osteoarthritis of the Z joints. v PMID:26118786

  4. A study on the reliability of measuring dynamic balance ability using a smartphone

    PubMed Central

    Han, Seulki; Lee, Daehee; Lee, Sangyong

    2016-01-01

    [Purpose] Evaluation of the reliability of smartphones as measuring equipment for dynamic balance ability was the goal of this study. [Subjects and Methods] Subjects were 30 healthy young students in their 20s. The first and second rounds of measurements were taken at a one-day interval to confirm test-retest reliability. The subjects stood on the footboard of the Biodex Balance System. Balance was measured using a smart phone. [Results] Acceleration rates corresponding to subjects with open eyes were 2.7 ± 2.2 (first measurement) and 3.3 ± 1.5 (second measurement), and the interclass correlation coefficient ICC (1,1) was 0.8. Acceleration rates corresponding to subjects with closed eyes were 4.1 ± 2.4 (first measurement) and 4.5 ± 1.8 (second measurement), and the ICC (1,1) was 0.9. Gyroscope rates corresponding to subjects with open eyes were 1.7 ± 1.2 (first measurement) and 2.3 ± 1.5 (second measurement), and the ICC (1,1) was 0.7. Gyroscope rates corresponding to subjects with closed eyes were 6.7 ± 2.4 (first measurement) and 6.6 ± 2.3 (second measurement), and the ICC (1,1) was 0.6. [Conclusion] The results of this study suggest that smartphones have sufficient potential as measuring equipment for dynamic balance ability. PMID:27799682

  5. Reliability of the step phase detection using inertial measurement units: pilot study

    PubMed Central

    Sessa, Salvatore; Zecca, Massimiliano; Bartolomeo, Luca; Takashima, Takamichi; Fujimoto, Hiroshi

    2015-01-01

    The use of inertial sensors for the gait event detection during a long-distance walking, for example, on different surfaces and with different walking patterns, is important to evaluate the human locomotion. Previous studies demonstrated that gyroscopes on the shank or foot are more reliable than accelerometers and magnetometers for the event detection in case of normal walking. However, these studies did not link the events with the temporal parameters used in the clinical practice; furthermore, they did not clearly verify the optimal position for the sensors depending on walking patterns and surface conditions. The event detection quality of the sensors is compared with video, used as ground truth, according to the parameters proposed by the Gait and Clinical Movement Analysis Society. Additionally, the performance of the sensor on the foot is compared with the one on the shank. The comparison is performed considering both normal walking and deviations to the walking pattern, on different ground surfaces and with or without constraints on movements. The preliminary results show that the proposed methodology allows reliable detection of gait events, even in case of abnormal footfall and in slipping surface conditions, and that the optimal location to place the sensors is the shank. PMID:26609406

  6. Isokinetic muscle testing for weak patients suffering from neuromuscular disorders: a reliability study.

    PubMed

    Tiffreau, Vincent; Ledoux, Isabelle; Eymard, Bruno; Thévenon, André; Hogrel, Jean-Yves

    2007-07-01

    Precise, sensitive muscle strength testing methods are needed to investigate muscle function in patients with neuromuscular disorders (NMD). Here, we describe an isokinetic knee flexor and extensor testing procedure using the Biodex 3's continuous passive motion (CPM) mode. The torque values recorded during passive isokinetic motion were subtracted from the torque values obtained for the same movement with maximal, concentric effort. The aims of the present study were to (i) evaluate the method's reliability in NMD patients presenting mild to severe muscle weakness and (ii) study the relationship between manual muscle testing (MMT) and isokinetic dynamometry. The fifteen participating patients were tested twice; the respective intraclass correlation coefficients (ICCs) for the two sessions ranged from 0.91 to 0.99 for the peak torque, work and power and from 0.50 to 0.90 for the angle at peak torque. The Spearman rho correlation coefficients comparing isokinetic values and MMT values ranged from 0.67 to 0.74 (p<0.01). This reliable, dynamic method appears to be of great value in NMD evaluation when sensitive strength measurement at the knee is required.

  7. [The external evaluation of study quality: the role in maintaining the reliability of laboratory information].

    PubMed

    Men'shikov, V V

    2013-08-01

    The external evaluation of quality of clinical laboratory examinations was gradually introduced in USSR medical laboratories since 1970s. In Russia, in the middle of 1990 a unified all-national system of external evaluation quality was organized known as the Federal center of external evaluation of quality at the basis of laboratory of the state research center of preventive medicine. The main positions of policy in this area were neatly formulated in the guidance documents of ministry of Health. Nowadays, the center of external evaluation of quality proposes 100 and more types of control studies and permanently extends their specter starting from interests of different disciplines of clinical medicine. The consistent participation of laboratories in the cycles of external evaluation of quality intrinsically promotes improvement of indicators of properness and precision of analysis results and increases reliability of laboratory information. However, a significant percentage of laboratories does not participate at all in external evaluation of quality or takes part in control process irregularly and in limited number of tests. The managers of a number of medical organizations disregard the application of the proposed possibilities to increase reliability of laboratory information and limit financing of studies in the field of quality control. The article proposes to adopt the national standard on the basis of ISO 17043 "Evaluation of compliance. The common requirements of professional competence testing".

  8. The Validity and Reliability of the Parent Fever Management Scale: A Study from Palestine.

    PubMed

    Zyoud, Sa'ed H; Al-Jabi, Samah W; Nabulsi, Masa M; Tubaila, Mais F; Sweileh, Waleed M; Awang, Rahmat; Walsh, Anne

    2015-08-01

    Parental concern about childhood fever and consequent use of antipyretics is increasing. Little is known about childhood fever management among Arab parents. No scales to measure parents' fever management practices in Palestine are available. The aim of this study was to validate the Arabic version of the Parent Fever Management Scale (PFMS) using a sample of parents in Palestine. A standard "forward-backward" procedure was used to translate PFMS into Arabic language. It was then validated on a convenience sample of 402 parents between July and October 2012. Descriptive statistics were used, and instrument reliability was assessed for internal consistency using Cronbach's alpha coefficient. Validity was confirmed using convergent and known group validation. Applying the recommended scoring method, the median (interquartile range) score of the PFMS was 26 (23-30). Acceptable internal consistency was found (Cronbach's alpha = 0.733) and the test-retest reliability value was 0.92 (P < 0.001). The Chi squared (χ (2)) test showed a significant relationship between PFMS groups and frequent daily administration of antipyretic groups (χ (2) = 52.86; P < 0.001). The PFMS sensitivity and specificity were 77.67 and 57.75 %, respectively. The positive and negative predictive values were 67.89 and 32.11 %, respectively. The Arabic version of the PFMS is a reliable and valid measure and can be used as a useful tool for health professionals to identify parents' fever management practices. The Arabic version of the PFMS can be used to reduce unnecessary parental practices in fever management for a febrile child.

  9. A Study on the Thermomechanical Reliability Risks of Through-Silicon-Vias in Sensor Applications

    PubMed Central

    Shao, Shuai; Liu, Dapeng; Niu, Yuling; O’Donnell, Kathy; Sengupta, Dipak; Park, Seungbae

    2017-01-01

    Reliability risks for two different types of through-silicon-vias (TSVs) are discussed in this paper. The first is a partially-filled copper TSV, if which the copper layer covers the side walls and bottom. A polymer is used to fill the rest of the cavity. Stresses in risk sites are studied and ranked for this TSV structure by FEA modeling. Parametric studies for material properties (modulus and thermal expansion) of TSV polymer are performed. The second type is a high aspect ratio TSV filled by polycrystalline silicon (poly Si). Potential risks of the voids in the poly Si due to filling defects are studied. Fracture mechanics methods are utilized to evaluate the risk for two different assembly conditions: package assembled to printed circuit board (PCB) and package assembled to flexible substrate. The effect of board/substrate/die thickness and the size and location of the void are discussed. PMID:28208758

  10. A Study on the Thermomechanical Reliability Risks of Through-Silicon-Vias in Sensor Applications.

    PubMed

    Shao, Shuai; Liu, Dapeng; Niu, Yuling; O'Donnell, Kathy; Sengupta, Dipak; Park, Seungbae

    2017-02-09

    Reliability risks for two different types of through-silicon-vias (TSVs) are discussed in this paper. The first is a partially-filled copper TSV, if which the copper layer covers the side walls and bottom. A polymer is used to fill the rest of the cavity. Stresses in risk sites are studied and ranked for this TSV structure by FEA modeling. Parametric studies for material properties (modulus and thermal expansion) of TSV polymer are performed. The second type is a high aspect ratio TSV filled by polycrystalline silicon (poly Si). Potential risks of the voids in the poly Si due to filling defects are studied. Fracture mechanics methods are utilized to evaluate the risk for two different assembly conditions: package assembled to printed circuit board (PCB) and package assembled to flexible substrate. The effect of board/substrate/die thickness and the size and location of the void are discussed.

  11. Preliminary Assessment of the Relative Toxicity of 1,5-Diazido-3- Nitrazapentane 90-Day Dermal Application Male and Female Rabbits Study Number 75-51-Y809-90, May 1990 - June 1992. Phase 2

    DTIC Science & Technology

    1992-06-01

    blood samples were collected by the cephalic ear artery from both male and female rabbits each dose group. Tables 4 and 5 list the clinical chemistry and...4. CLINICAL CHEMISTRY Serum Glutamic Oxaloacetic Transaminase (SGOT) (AST) (Aspartate Aminotransferase) Serum Glutamic Pyruvic Transaminase (SGPT...Appendices C-L). (3) The clinical chemistry values (Appendices I and J) showed a significant change in total protein in the 78 mg/kg group for male rabbits and

  12. Toward lean satellites reliability improvement using HORYU-IV project as case study

    NASA Astrophysics Data System (ADS)

    Faure, Pauline; Tanaka, Atomu; Cho, Mengu

    2017-04-01

    Lean satellite programs are programs in which the satellite development philosophy is driven by fast delivery and low cost. Though this concept offers the possibility to develop and fly risky missions without jeopardizing a space program, most of these satellites suffer infant mortality and fail to achieve their mission minimum success. Lean satellites with high infant mortality rate indicate that testing prior to launch is insufficient. In this study, the authors monitored failures occurring during the development of the lean satellite HORYU-IV to identify the evolution of the cumulative number of failures against cumulative testing time. Moreover, the sub-systems driving the failures depending on the different development phases were identified. The results showed that half to 2/3 of the failures are discovered during the early stage of testing. Moreover, when the mean time before failure was calculated, it appeared that for any development phase considered, a new failure appears on average every 20 h of testing. Simulations were also performed and it showed that for an initial testing time of 50 h, reliability after 1 month launch can be improved by nearly 6 times as compared to an initial testing time of 20 h. Through this work, the authors aim at providing a qualitative reference for lean satellites developers to better help them manage resources to develop lean satellites following a fast delivery and low cost philosophy while ensuring sufficient reliability to achieve mission minimum success.

  13. A reliability-based calibration study for upheaval buckling of pipelines

    SciTech Connect

    Moerk, K.J.; Bjoernsen, T.; Venaas, A.; Thorkildsen, F.

    1995-12-31

    When a pipeline is subjected to axial compressive loads it will try to extend and release the compression force. If the pipeline is restrained by a soil or rock cover forces will be established between the pipeline and the soil. Upheaval buckling will occur when the force exerted by the pipe on the soil exceeds the vertical restraint. The pipeline moves upwards leading to possible unacceptable local plastic deformations or collapse or making it vulnerable to fishing gear and other third party activities. The present paper describes a reliability-based design procedure against upheaval buckling of rock or soil covered pipelines. The study is performed using state-of-the-art design methodologies including an assessment of all known uncertainties related to the load and capacity, measurement, surveys and confidence in the applied models. A response surface technique is applied within the level 3 reliability analysis. Target safety levels are discussed and a case specific calibration of partial safety factors in a consistent design equation against upheaval buckling is performed. Finally, a set of safety factors are proposed for both SLS and ULS requirements.

  14. Reliability and validity of the tritrac-R3D accelerometer during backpacking: a case study.

    PubMed

    DeVoe, D; Dalleck, L

    2001-08-01

    This study investigated the utility of the Tritrac-R3D accelerometer as a reliable and valid instrument in the quantification of physical activity while backpacking in the field and to evaluate heart-rate responses and oxygen consumption to assess the feasibility of using the Tritrac-R3D to estimate caloric expenditure. Two 7-day backpacking expeditions were conducted in two consecutive years by a single subject at Grand Canyon National Park, Arizona. The average hiking heart rate ranged front 60% to 77% HRmax during the expeditions. The average rate of estimated caloric cost ranged from 6.8 to 11.7 kcals x min.(-1) (equivalent to 408 to 702 kcals x hr.(-1)), indicating a relatively moderate to high level of exertion. The Tritrac had adequate consistency and reliability in the field between the two expeditions in recorded activity counts. The Tritrac underestimated caloric expenditure during backpacking with changes in terrain, and hiking speed contributed to even greater disparity in accuracy.

  15. Reliability of primary caregivers reports on lifestyle behaviours of European pre-school children: the ToyBox-study.

    PubMed

    González-Gil, E M; Mouratidou, T; Cardon, G; Androutsos, O; De Bourdeaudhuij, I; Góźdź, M; Usheva, N; Birnbaum, J; Manios, Y; Moreno, L A

    2014-08-01

    Reliable assessments of health-related behaviours are necessary for accurate evaluation on the efficiency of public health interventions. The aim of the current study was to examine the reliability of a self-administered primary caregivers questionnaire (PCQ) used in the ToyBox-intervention. The questionnaire consisted of six sections addressing sociodemographic and perinatal factors, water and beverages consumption, physical activity, snacking and sedentary behaviours. Parents/caregivers from six countries (Belgium, Bulgaria, Germany, Greece, Poland and Spain) were asked to complete the questionnaire twice within a 2-week interval. A total of 93 questionnaires were collected. Test-retest reliability was assessed using intra-class correlation coefficient (ICC). Reliability of the six questionnaire sections was assessed. A stronger agreement was observed in the questions addressing sociodemographic and perinatal factors as opposed to questions addressing behaviours. Findings showed that 92% of the ToyBox PCQ had a moderate-to-excellent test-retest reliability (defined as ICC values from 0.41 to 1) and less than 8% poor test-retest reliability (ICC < 0.40). Out of the total ICC values, 67% showed good-to-excellent reliability (ICC from 0.61 to 1). We conclude that the PCQ is a reliable tool to assess sociodemographic characteristics, perinatal factors and lifestyle behaviours of pre-school children and their families participating in the ToyBox-intervention.

  16. Scoping study on trends in the economic value of electricity reliability to the U.S. economy

    SciTech Connect

    Eto, Joseph; Koomey, Jonathan; Lehman, Bryan; Martin, Nathan; Mills, Evan; Webber, Carrie; Worrell, Ernst

    2001-06-01

    During the past three years, working with more than 150 organizations representing public and private stakeholders, EPRI has developed the Electricity Technology Roadmap. The Roadmap identifies several major strategic challenges that must be successfully addressed to ensure a sustainable future in which electricity continues to play an important role in economic growth. Articulation of these anticipated trends and challenges requires a detailed understanding of the role and importance of reliable electricity in different sectors of the economy. This report is intended to contribute to that understanding by analyzing key aspects of trends in the economic value of electricity reliability in the U.S. economy. We first present a review of recent literature on electricity reliability costs. Next, we describe three distinct end-use approaches for tracking trends in reliability needs: (1) an analysis of the electricity-use requirements of office equipment in different commercial sectors; (2) an examination of the use of aggregate statistical indicators of industrial electricity use and economic activity to identify high reliability-requirement customer market segments; and (3) a case study of cleanrooms, which is a cross-cutting market segment known to have high reliability requirements. Finally, we present insurance industry perspectives on electricity reliability as an example of a financial tool for addressing customers' reliability needs.

  17. The revised scale for caregiving self-efficacy: reliability and validity studies.

    PubMed

    Steffen, Ann M; McKibbin, Christine; Zeiss, Antonette M; Gallagher-Thompson, Dolores; Bandura, Albert

    2002-01-01

    Two samples of family caregivers (Study 1: N = 169; Study 2: N = 145) of cognitively impaired older adults were used to revise, extend, and evaluate a measure of perceived self-efficacy for caregiving tasks. The Revised Scale for Caregiving Self-Efficacy measures 3 domains of caregiving self-efficacy: Obtaining Respite, Responding to Disruptive Patient Behaviors, and Controlling Upsetting Thoughts. The 3 subscales show strong internal consistency and adequate test-retest reliability. Construct validity is supported by relationships between these 3 facets of perceived caregiving efficacy and depression, anxiety, anger, perceived social support, and criticism expressed in speech samples. The Revised Scale for Caregiving Self-Efficacy has potential uses for both research and clinical purposes.

  18. Teleradiology Assessment of Computerized Tomographs Online Reliability Study (TRACTORS) for acute stroke evaluation.

    PubMed

    Johnston, Karen C; Worrall, Bradford B

    2003-01-01

    Telemedicine has potential to increase the use of tissue plasminogen activator (t-PA) for ischemic stroke and is increasingly offered to provide stroke expertise to remote and underserved areas. The accuracy of stroke neurologists' use of telemedicine to read head computed tomography scans (CT) has not been demonstrated. We sought to determine the validity and reliability of neurologists' reading of acute stroke head CTs via teleradiology. The pilot study compared stroke neurologists' reading of CTs via teleradiology to gold standard readings of hard copies on a view box. Head CTs obtained during consecutive acute evaluations for thrombolytic therapy between February and July 2001 were used. For this study, each stroke neurologist was masked to all prior readings, clinical decisions regarding thrombolysis eligibility, and the reading of the other study neurologist. Each neurologist read one-half of the CT scans using teleradiology and the other one-half using a view box. We used the official reading by a neuroradiologist for comparison. The kappa statistic measured reliability. Validity was measured by sensitivity and specificity. Sixty scans were used for the analysis. The neurologists identified the same four hemorrhages using teleradiology that they and the neuroradiologist identified using the light board. Compared to the readings on a view box, the kappa statistic for eligibility for thrombolysis via teleradiology was 1.0. Sensitivity was 100%, 95% CI = (0.93, 1.0); specificity was 100%, 95% CI = (0.40, 0.98) in both comparisons. This pilot study provides encouraging preliminary evidence that neurologists with stroke expertise can determine radiological intravenous t-PA eligibility via teleradiology. Further analysis in a larger sample is necessary to validate these results.

  19. Application of an LC-MS/MS method for reliable determination of amodiaquine, N-desethylamodiaquine, artesunate and dihydroartemisinin in human plasma for a bioequivalence study in healthy Indian subjects.

    PubMed

    Rathod, Dhiraj M; Patel, Keyur R; Mistri, Hiren N; Jangid, Arvind G; Shrivastav, Pranav S; Sanyal, Mallika

    2016-05-30

    A sensitive and high throughput bioanalytical method has been developed for reliable determination of amodiaquine (AQ), N-desethylamodiaquine (DEAQ), artesunate (AS) and dihydroartemisinin (DHA) in human plasma by LC-MS/MS. The method employs a solid phase extraction procedure without an evaporation step and with optimum use of organic solvents to circumvent degradation of artemisinin derivatives. The analytes and their deuterated internal standards (ISs) were analyzed on Hypersil Gold (100 mm × 4.6mm, 5 μm) column using acetonitrile and 2.0mM ammonium formate (pH 2.50) in 80:20 (v/v) ratio as the mobile phase. A triple quadrupole mass spectrometer equipped with an electrospray ionization interface was used to detect and quantify the analytes. The method was established over the concentration range of 0.250-30.0 ng/mL, 1.50-180 ng/mL, 2.00-600 ng/mL and 5.00-1400 ng/mL for AQ, DEAQ, AS and DHA respectively using 250 μL human plasma. The intra-day and inter-day accuracy and precision (% CV) across quality controls varied from 93.3-105.0% and 1.7-8.3 respectively for all the analytes. The stability was assessed in whole blood as well as in plasma samples under different conditions. All four analytes were stable in whole blood up to 2h on melting ice. The long term stability in plasma was ascertained up to 90 days. IS-normalized matrix factors ranged from 0.988-1.023 for all the analytes. The method was successfully applied to a bioequivalence study using 50mg artesunate and 135 mg amodiaquine fixed dose formulation in 14 healthy subjects.

  20. Ultrasound assessment of transverse carpal ligament thickness: a validity and reliability study.

    PubMed

    Shen, Zhilei Liu; Li, Zong-Ming

    2012-06-01

    The transverse carpal ligament (TCL) forms the palmar boundary of the carpal tunnel and plays an important role in carpal tunnel mechanics. TCL hypertrophy has been observed for individuals with carpal tunnel syndrome (CTS) and postulated as a potential etiologic factor. Ultrasound is particularly advantageous for TCL imaging because of its capability of detecting the interfaces between the TCL and other tissues. The purposes of this study were to develop an ultrasound based method to measure the TCL thickness and to test the validity and reliability of this method. Three operators conducted two sessions of ultrasound examination on eight cadaveric specimens and eight healthy volunteers. A custom script was used to calculate TCL thickness along the TCL length from the ultrasound images. The ultrasound based TCL thickness of the cadaveric specimens was compared with the dissection based TCL thickness for validation. The results showed Pearson's correlation coefficients of 0.867-0.928, intraclass correlation coefficient (ICC) values of 0.726-0.865, a standard error of measurement of 0.02-0.07 mm and a minimal detectable difference of 0.05-0.15 mm. The high correlation coefficients and small errors indicate that the ultrasound based method is valid for measuring TCL thickness. Furthermore, ultrasound measurements showed excellent intraoperator and interoperator reliability with ICC values as 0.826-0.933 and 0.840-0.882, respectively. The ultrasound based TCL thickness was in the range of 0.93-2.34 (1.54 ± 0.33) mm and agreed well with previous studies. The ultrasound method developed in this study is a valuable tool to examine morphologic properties of healthy and pathologic TCLs.

  1. Lessons Learned on Benchmarking from the International Human Reliability Analysis Empirical Study

    SciTech Connect

    Ronald L. Boring; John A. Forester; Andreas Bye; Vinh N. Dang; Erasmia Lois

    2010-06-01

    The International Human Reliability Analysis (HRA) Empirical Study is a comparative benchmark of the prediction of HRA methods to the performance of nuclear power plant crews in a control room simulator. There are a number of unique aspects to the present study that distinguish it from previous HRA benchmarks, most notably the emphasis on a method-to-data comparison instead of a method-to-method comparison. This paper reviews seven lessons learned about HRA benchmarking from conducting the study: (1) the dual purposes of the study afforded by joining another HRA study; (2) the importance of comparing not only quantitative but also qualitative aspects of HRA; (3) consideration of both negative and positive drivers on crew performance; (4) a relatively large sample size of crews; (5) the use of multiple methods and scenarios to provide a well-rounded view of HRA performance; (6) the importance of clearly defined human failure events; and (7) the use of a common comparison language to “translate” the results of different HRA methods. These seven lessons learned highlight how the present study can serve as a useful template for future benchmarking studies.

  2. The modified patient enablement instrument: a Portuguese cross-cultural adaptation, validity and reliability study

    PubMed Central

    Remelhe, Mafalda; Teixeira, Pedro M; Lopes, Irene; Silva, Luís; Correia de Sousa, Jaime

    2017-01-01

    Enabling patients with asthma to obtain the knowledge, confidence and skills they need in order to assume a major role in the management of their disease is cost effective. It should be an integral part of any plan for long-term control of asthma. The modified Patient Enablement Instrument (mPEI) is an easily administered questionnaire that was adapted in the United Kingdom to measure patient enablement in asthma, but its applicability in Portugal is not known. Validity and reliability of questionnaires should be tested before use in settings different from those of the original version. The purpose of this study was to test the applicability of the mPEI to Portuguese asthma patients after translation and cross-cultural adaptation, and to verify the structural validity, internal consistency and reproducibility of the instrument. The mPEI was translated to Portuguese and back translated to English. Its content validity was assessed by a debriefing interview with 10 asthma patients. The translated instrument was then administered to a random sample of 142 patients with persistent asthma. Structural validity and internal consistency were assessed. For reproducibility analysis, 86 patients completed the instrument again 7 days later. Item-scale correlations and exploratory factor analysis were used to assess structural validity. Cronbach’s alpha was used to test internal consistency, and the intra-class correlation coefficient was used for the analysis of reproducibility. All items of the Portuguese version of the mPEI were found to be equivalent to the original English version. There were strong item-scale correlations that confirmed construct validity, with a one component structure and good internal consistency (Cronbach’s alpha >0.8) as well as high test–retest reliability (ICC=0.85). The mPEI showed sound psychometric properties for the evaluation of enablement in patients with asthma making it a reliable instrument for use in research and clinical practice

  3. Meta-analysis of the reliability and validity of Part B of the Index of Work Satisfaction across studies.

    PubMed

    Zangaro, George A; Soeken, Karen L

    2005-01-01

    Nurses' job satisfaction is a crucial factor in health care organizations. This study uses meta-analysis for reliability generalization and synthesis of construct validity of Part B of the Index of Work Satisfaction (IWS), a measure of job satisfaction. Meta-analysis was performed including assessments of study quality and descriptive coding of studies. Rater reliability was assessed for all coding and extraction of data. The mean reliability of Part B scores of the IWS based on 14 studies was .78 (df = 13, p < .05). The mean score reliability was .77 for university settings, .73 for community/acute care hospitals, .77 for multi-site studies, and .90 for other settings. For studies rated high and low quality, the mean score reliability was .77 and .83, respectively. Scores on Part B of the IWS correlated -.38 with turnover intent, .60 with organizational commitment, and -.53 with job stress. Scores on Part B of the IWS are reliable for measuring job satisfaction of nurses across samples. Construct validity needs additional testing.

  4. Reliability study on high power 638-nm triple emitter broad area laser diode

    NASA Astrophysics Data System (ADS)

    Yagi, T.; Kuramoto, K.; Kadoiwa, K.; Wakamatsu, R.; Miyashita, M.

    2016-03-01

    Reliabilities of the 638-nm triple emitter broad area laser diode (BA-LD) with the window-mirror structure were studied. Methodology to estimate mean time to failure (MTTF) due to catastrophic optical mirror degradation (COMD) in reasonable aging duration was newly proposed. Power at which the LD failed due to COMD (PCOMD) was measured for the aged LDs under the several aging conditions. It was revealed that the PCOMD was proportional to logarithm of aging duration, and MTTF due to COMD (MTTF(COMD)) could be estimated by using this relation. MTTF(COMD) estimated by the methodology with the aging duration of approximately 2,000 hours was consistent with that estimated by the long term aging. By using this methodology, the MTTF of the BA-LD was estimated exceeding 100,000 hours under the output of 2.5 W, duty cycles of 30% .

  5. Use of Melt Flow Rate Test in Reliability Study of Thermoplastic Encapsulation Materials in Photovoltaic Modules

    SciTech Connect

    Moseley, J.; Miller, D.; Shah, Q.-U.-A. S. J.; Sakurai, K.; Kempe, M.; Tamizhmani, G.; Kurtz, S.

    2011-10-01

    Use of thermoplastic materials as encapsulants in photovoltaic (PV) modules presents a potential concern in terms of high temperature creep, which should be evaluated before thermoplastics are qualified for use in the field. Historically, the issue of creep has been avoided by using thermosetting polymers as encapsulants, such as crosslinked ethylene-co-vinyl acetate (EVA). Because they lack crosslinked networks, however, thermoplastics may be subject to phase transitions and visco-elastic flow at the temperatures and mechanical stresses encountered by modules in the field, creating the potential for a number of reliability and safety issues. Thermoplastic materials investigated in this study include PV-grade uncured-EVA (without curing agents and therefore not crosslinked); polyvinyl butyral (PVB); thermoplastic polyurethane (TPU); and three polyolefins (PO), which have been proposed for use as PV encapsulation. Two approaches were used to evaluate the performance of these materials as encapsulants: module-level testing and a material-level testing.

  6. Brief Report: An Exploratory Study of the Diagnostic Reliability for Autism Spectrum Disorder.

    PubMed

    Taylor, Lauren J; Eapen, Valsamma; Maybery, Murray; Midford, Sue; Paynter, Jessica; Quarmby, Lyndsay; Smith, Timothy; Williams, Katrina; Whitehouse, Andrew J O

    2017-02-23

    Previous research shows inconsistency in clinician-assigned diagnoses of Autism Spectrum Disorder (ASD). We conducted an exploratory study that examined the concordance of diagnoses between a multidisciplinary assessment team and a range of independent clinicians throughout Australia. Nine video-taped Autism Diagnostic Observation Schedule (ADOS) assessments were collected from two Australian sites. Twenty-seven Australian health professionals each observed two video-recordings and rated the degree to which the individual met the DSM-5 criteria for ASD. There was 100% agreement on the diagnostic classification for only 3 of the 9 video clips (33%), with the remaining 6 clips (66%) reaching poor reliability. In addition, only 24% of the participating clinicians achieved 'good' or 'excellent' levels of agreement (Cohen's kappa > 0.6) with the original ASD assessment. These findings have implications for clinical guidelines for ASD assessments.

  7. Scale reliability and construct validity: a pilot study among primary school children in Northern Tanzania.

    PubMed

    Seha, A M; Klepp, K I; Ndeki, S S

    1994-12-01

    Based on the World Health Organization's standardized survey inventories assessing AIDS-related knowledge, attitudes, beliefs, and practices (KABP) for adolescents, a written questionnaire was developed and pilot tested among primary school children in Northern Tanzania. Subjects included 472 fifth and sixth graders at four schools in Arusha and Kilimanjaro regions. Results indicated that the large majority of the students understood the questions and were able and willing to complete the survey. Non-response patterns did not seem to be related to the sensitivity of included questions. AIDS-related knowledge and attitudes toward engaging in sexual behavior had acceptable reliability and construct validity when compared with similar surveys in Western countries, while perceived social norms and self-efficacy need further development. KABP questionnaires may serve as a useful method in AIDS-related surveys and evaluation studies among school children in Tanzania if survey instruments are adapted to reflect the local social and cultural context.

  8. Validity and reliability of the critical care pain observation tool: a replication study.

    PubMed

    Keane, Kathleen Marie

    2013-12-01

    Critically ill patients are often not able to self-report the presence of pain. Currently there is no generally accepted assessment tool for this population. The Critical-Care Pain Observation Tool (CPOT) was developed for pain assessment of critically ill patients. The purpose of this study was to replicate the findings of the Gelinas et al. (2006) CPOT reference study and examine the interrater reliability (IRR), discriminant validity (DV), and criterion validity (CV) of the CPOT. This quantitative study used a repeated measures design with a convenience sample of 21 postoperative open heart surgery patients cared for in a tertiary-care teaching hospital. Testing for IRR in this sample showed a range of results resulting in fair to almost perfect IRR; the findings of this study suggest that the instrument's IRR is acceptable but variable. Testing for DV demonstrated a significant difference in mean scores between noxious (painful) and nonnoxious (nonpainful) procedures. Testing for CV showed a weak nonsignificant Spearman correlation of 0.26 (P < .312) between CPOT scores and patient self-report during repositioning after extubation. This replication study adds to four studies that have examined psychometric attributes of the instrument and contributes to the process of translating the use of this instrument to the clinical setting.

  9. A study of the reliability and comparative validity of the cardia dietary history.

    PubMed

    Liu, K; Slattery, M; Jacobs, D; Cutter, G; McDonald, A; Van Horn, L; Hilner, J E; Caan, B; Bragg, C; Dyer, A

    1994-01-01

    This study evaluated the reliability and comparative validity of the dietary history survey method developed for CARDIA, a longitudinal investigation of life-styles and the evolution of cardiovascular risk factors in young adults. The method was tested in a sample of 30 white men, 33 white women, 33 black men, and 32 black women, aged 18 to 35 years, in four regions reflecting the race, sex, age, and geographical distribution of CARDIA participants. For 64 of the participants, two dietary history interviews, 1 month apart, were conducted by trained nutritionists. These data were used to examine the reliability of the method. For all participants, seven telephone- assessed 24-hour dietary recalls were randomly scheduled during a 28-day period and were followed by a dietary history interview. These data were used to examine the comparative validity of the method. Calories, total fat, saturated fat, polyunsaturated fat, monounsaturated fat, dietary cholesterol, protein, carbohydrate, alcohol, potassium, calcium, and vitamin A were selected by the CARDIA Nutrition Working Group as the nutrients for comparison. Mean nutrient values from the first history tended to be higher than those obtained from the last history. However, for a majority of the nutrients, the differences were significant for blacks but not for whites. The correlations for the log-transformed nutrient values and calorie-adjusted nutrient values from the two histories were generally in the range of 0.50 to 0.80 for whites. For blacks, the correlations were lower, with a majority in the range of 0.30 to 0.70. The average nutrient values estimated from the histories were higher than those estimated from the average of the seven 24-hour recalls. The differences in blacks were larger than in whites. For both the log-transformed nutrient values and the calorie-adjusted nutrient values, the correlations between the two methods were generally larger than 0.50 for whites. However, for blacks, the correlations

  10. Feasibility and Reliability of Physical Fitness Tests in Older Adults with Intellectual Disability: A Pilot Study

    ERIC Educational Resources Information Center

    Hilgenkamp, Thessa I. M.; van Wijck, Ruud; Evenhuis, Heleen M.

    2012-01-01

    Background: Physical fitness is relevant for wellbeing and health, but knowledge on the feasibility and reliability of instruments to measure physical fitness for older adults with intellectual disability is lacking. Methods: Feasibility and test-retest reliability of a physical fitness test battery (Box and Block Test, Response Time Test, walking…

  11. Increasing Score Reliability with Item-Pattern Scoring: An Empirical Study in Several Score Metrics.

    ERIC Educational Resources Information Center

    Yen, Wendy M.; Candell, Gregory L.

    Reliabilities are compared for two types of test score data: number correct, and item response patterns. Item-pattern scoring using three-parameter item response theory takes into account how many and which items a student answers correctly. This procedure theoretically results in greater reliability than does number-correct scoring. Empirical…

  12. Vibration testing: a pilot study investigating the intra-tester reliability of the Vibrameter for the Median and Ulnar nerves.

    PubMed

    James, Gill; Scott, Claire

    2012-08-01

    The measurement of vibration thresholds (VTs) is a sensitive test for identifying and monitoring neuropathies. Such a test needs established reliability. The purpose of this research was to evaluate the intra-tester reliability of VT measurements of the Median and Ulnar nerves in asymptomatic participants. A double blinded repeated measures study was carried out. The VTs of the Median and Ulnar nerves were measured on two occasions with seven days between measurements. Participants were trained in identifying the sensation before commencing measurement. 22 participants who fulfilled the inclusion criteria were recruited. Intra-rater reliability was analysed used the intra-class correlation. The median nerve showed excellent reliability (ICC = .922; standard error of the mean = .0225 μm; 'true' SEM = .045 μm; smallest real difference = .062 μm). Ulnar nerve reliability was 'substantial' (ICC = .632; standard error of the mean = .0225 μm; 'true' SEM = .055 μm; smallest real difference = .085 μm). The VT measurements showed excellent to substantial reliability. The Vibrameter has the potential for excellent reliability providing manual therapists practice the technique of using it. It could usefully be considered by manual therapists to support their practice.

  13. Reliability of Current Biokinetic and Dosimetric Models for Radionuclides: A Pilot Study

    SciTech Connect

    Leggett, Richard Wayne; Eckerman, Keith F; Meck, Robert A.

    2008-10-01

    This report describes the results of a pilot study of the reliability of the biokinetic and dosimetric models currently used by the U.S. Nuclear Regulatory Commission (NRC) as predictors of dose per unit internal or external exposure to radionuclides. The study examines the feasibility of critically evaluating the accuracy of these models for a comprehensive set of radionuclides of concern to the NRC. Each critical evaluation would include: identification of discrepancies between the models and current databases; characterization of uncertainties in model predictions of dose per unit intake or unit external exposure; characterization of variability in dose per unit intake or unit external exposure; and evaluation of prospects for development of more accurate models. Uncertainty refers here to the level of knowledge of a central value for a population, and variability refers to quantitative differences between different members of a population. This pilot study provides a critical assessment of models for selected radionuclides representing different levels of knowledge of dose per unit exposure. The main conclusions of this study are as follows: (1) To optimize the use of available NRC resources, the full study should focus on radionuclides most frequently encountered in the workplace or environment. A list of 50 radionuclides is proposed. (2) The reliability of a dose coefficient for inhalation or ingestion of a radionuclide (i.e., an estimate of dose per unit intake) may depend strongly on the specific application. Multiple characterizations of the uncertainty in a dose coefficient for inhalation or ingestion of a radionuclide may be needed for different forms of the radionuclide and different levels of information of that form available to the dose analyst. (3) A meaningful characterization of variability in dose per unit intake of a radionuclide requires detailed information on the biokinetics of the radionuclide and hence is not feasible for many infrequently

  14. Validity and inter-rater reliability of inertial gait measurements in Parkinson's disease: a pilot study.

    PubMed

    Esser, Patrick; Dawes, Helen; Collett, Johnny; Feltham, Max G; Howells, Ken

    2012-03-30

    Walking models driven by centre of mass (CoM) data obtained from inertial measurement units (IMU) or optical motion capture systems (OMCS) can be used to objectively measure gait. However current models have only been validated within typical developed adults (TDA). The purpose of this study was to compare the projected CoM movement within Parkinson's disease (PD) measured by an IMU with data collected from an OMCS after which spatio-temporal gait measures were derived using an inverted pendulum model. The inter-rater reliability of spatio-temporal parameters was explored between expert researchers and clinicians using the IMU processed data. Participants walked 10 m with an IMU attached over their centre of mass which was simultaneously recorded by an OMCS. Data was collected on two occasions, each by an expert researcher and clinician. Ten people with PD showed no difference (p=0.13) for vertical, translatory acceleration, velocity and relative position of the projected centre of mass between IMU and OMCS data. Furthermore no difference (p=0.18) was found for the derived step time, stride length and walking speed for people with PD. Measurements of step time (p=0.299), stride length (p=0.883) and walking speed (p=0.751) did not differ between experts and clinicians. There was good inter-rater reliability for these parameters (ICC3.1=0.979, ICC3.1=0.958 and ICC3.1=0.978, respectively). The findings are encouraging and support the use of IMUs by clinicians to measure CoM movement in people with PD.

  15. A study on the reliability of indium solder die bonding of high power semiconductor lasers

    NASA Astrophysics Data System (ADS)

    Liu, Xingsheng; Davis, Ronald W.; Hughes, Lawrence C.; Rasmussen, Michael H.; Bhat, Rajaram; Zah, Chung-En; Stradling, Jim

    2006-07-01

    High power semiconductor lasers have found increased applications. Indium solder is one of the most widely used solders in high power laser die bonding. Indium solder has some advantages in laser die bonding. It also has some concerns, however, especially in terms of reliability. In this paper, the reliability of indium solder die bonding of high power broad area semiconductor lasers was studied. It was found that indium solder bonded lasers have much shorter lifetime than AuSn solder bonded devices. Catastrophic degradation was observed in indium solder bonded lasers. Nondestructive optical and acoustic microscopy was conducted during the lifetime testing to monitor the failure process and destructive failure analysis was performed after the lasers failed. It was found that the sudden failure was caused by electromigration of indium solder at the high testing current of up to 7A. It was shown that voids were created and gradually enlarged by indium solder electromigration, which caused local heating near the facets of the laser. The local heating induced catastrophic optical mirror damage (COMD) of the lasers. It was discussed that current crowding, localized high temperature, and large temperature gradient contributed to the fast indium solder electromigration. It was observed that some bright pattern structures appeared on the front facet of the indium solder bonded lasers after the devices failed and the bright patterns grew and spread upon further testing. Failure analysis showed that the bright pattern structure apparent on the front facet was due to crystallization of the TiOx material of the front facet coating as a result of overheating during lifetime testing. It was concluded that indium solder is not suitable for high power laser applications due to electromigration at high current densities and high temperatures.

  16. Instrument for assessing mobile technology acceptability in diabetes self-management: a validation and reliability study

    PubMed Central

    Frandes, Mirela; Deiac, Anca V; Timar, Bogdan; Lungeanu, Diana

    2017-01-01

    Background Nowadays, mobile technologies are part of everyday life, but the lack of instruments to assess their acceptability for the management of chronic diseases makes their actual adoption for this purpose slow. Objective The objective of this study was to develop a survey instrument for assessing patients’ attitude toward and intention to use mobile technology for diabetes mellitus (DM) self-management, as well as to identify sociodemographic characteristics and quality of life factors that affect them. Methods We first conducted the documentation and instrument design phases, which were subsequently followed by the pilot study and instrument validation. Afterward, the instrument was administered 103 patients (median age: 37 years; range: 18–65 years) diagnosed with type 1 or type 2 DM, who accepted to participate in the study. The reliability and construct validity were assessed by computing Cronbach’s alpha and using factor analysis, respectively. Results The instrument included statements about the actual use of electronic devices for DM management, interaction between patient and physician, attitude toward using mobile technology, and quality of life evaluation. Cronbach’s alpha was 0.9 for attitude toward using mobile technology and 0.97 for attitude toward using mobile device applications for DM self-management. Younger patients (Spearman’s ρ=−0.429; P<0.001) with better glycemic control (Spearman’s ρ=−0.322; P<0.001) and higher education level (Kendall’s τ=0.51; P<0.001) had significantly more favorable attitude toward using mobile assistive applications for DM control. Moreover, patients with a higher quality of life presented a significantly more positive attitude toward using modern technology (Spearman’s ρ=0.466; P<0.001). Conclusion The instrument showed good reliability and internal consistency, making it suitable for measuring the acceptability of mobile technology for DM self-management. Additionally, we found that even

  17. Reliability of Baropodometry on the Evaluation of Plantar Load Distribution: A Transversal Study

    PubMed Central

    Baumfeld, Daniel; da Rocha, Romário Lopes; Macedo, Benjamim; Raduan, Fernando; Zambelli, Roberto; Alves Silva, Thiago Alexandre

    2017-01-01

    Introduction. Baropodometry is used to measure the load distribution on feet during rest and walking. The aim of this study was to evaluate changes in plantar foot pressures distribution due to period of working and due to stretching exercises of the posterior muscular chain. Methods. In this transversal study, all participants were submitted to baropodometric evaluation at two different times: before and after the working period and before and after stretching the muscles of the posterior chain. Results. We analyzed a total of 54 feet of 27 participants. After the working period, there was an average increase in the forefoot pressure of 0.16 Kgf/cm2 and an average decrease in the hindfoot pressure of 0.17 Kgf/cm2. After stretching the posterior muscular chain, the average increase in the forefoot pressure was 0.56 Kgf/cm2 and the hindfoot average pressure decrease was 0.56 Kgf/cm2. These changes were not statistically significant. Discussion. It was reported that the strength of the Achilles tendon generates greater forefoot load transferred from the hindfoot. In our study, no significant variation in the distribution of plantar pressure was observed. It can be inferred that baropodometry was a reliable instrument to determine the plantar pressure, regardless of the tension of the posterior chain muscles. PMID:28349064

  18. Reliability of Fiber Tracking Measurements in Diffusion Tensor Imaging for Longitudinal Study

    PubMed Central

    Danielian, Laura E.; Iwata, Nobue K.; Thomasson, David M.; Floeter, Mary Kay

    2009-01-01

    The statistical reliability of diffusion property measurements was evaluated in ten healthy subjects using deterministic fiber tracking to localize tracts affected in motor neuron disease: corticospinal tract (CST), uncinate fasciculus (UNC), and the corpus callosum in its entirety (CC), and its genu (GE), motor (CCM), and splenium (SP) fibers separately. Measurements of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (λ1), transverse diffusivity (λ⊥), and volume of voxels containing fibers (VV) were obtained within each tract. To assess intra-rater and inter-rater reliability, two raters carried out fiber tracking five times on each scan. Scan-rescan and longitudinal reliability were assessed in a subset of four subjects who had six scans, with two sets of three scans separated by one year. The statistical reliability of repeated measurements was evaluated using intra-class correlation coefficients (ICC) and coefficients of variation (CV). Spatial agreement of tract shape was assessed using the kappa (κ) statistic. Results Repeated same-scan fiber tracking evaluations showed good geometric alignment (intra-rater κ > 0.90, inter-rater κ > 0.76) and reliable diffusion property measurements (intra-rater ICC > 0.92, inter-rater ICC > 0.77). FA, MD, and λ⊥ were highly reliable with repeated scans on different days, up to a year apart (ICC > 0.8). VV also exhibited good reliability, but with higher CVs. We were unable to demonstrate reproducibility of λ1. Longitudinal reliability after one year was improved by averaging measurements from multiple scans at each timepoint. Fiber tracking provides a reliable tool for the longitudinal evaluation of white matter diffusion properties. PMID:19744567

  19. A pilot study of the reliability of the dynamic mode of one BTE Work Simulator.

    PubMed

    Cetinok, E M; Renfro, R R; Coleman, E F

    1995-01-01

    This paper presents the results of a study of the reliability of the manual dynamic mode of one BTE Work Simulator. The study was part of an effort to develop a simple method of calibrating the BTE Work Simulator as an evaluation instrument. Weights attached to a 12-in nylon cylinder rotated the shaft of the exercise head against resistance generated by the Work Simulator. A timing device recorded drop times for one complete revolution of the nylon cylinder. The timing device consisted of a digital clock, a photo detector circuit, and a switching circuit. The photo detector recorded one revolution of the cylinder, and the switching circuit started and stopped the clock. Drop times were recorded as fixed weights attached to the nylon cylinder were allowed to drop. The test was repeated a number of times at each combination of weight and exercise level. A minimum of 40 tests were recorded with 4.96-, 10-, 15-, 25-, 30-, and 40-lb weights. This provided accurate measurement of the performance of the Work Simulator in the dynamic mode. Fluctuation in resistance caused drop times for any given weight to vary from -47% to +183.7% from the mean. In some cases the resistance fluctuation was sufficient to either prevent the weight from dropping or stop the weight before the cylinder had rotated one revolution. Resistance variation in the dynamic mode of the BTE Work Simulator was found to produce inconsistent performance. Testing that includes other Work Simulators is in progress.

  20. A Study on Electrical Reliability Criterion on Through Silicon Via Packaging.

    PubMed

    Lwo, Ben-Je; Tseng, Kuo-Hao; Tseng, Kun-Fu

    2016-06-01

    Three-dimensional (3D) structure with through silicon via (TSV) technology is emerging as a key issue in microelectronic packaging industry, and electrical reliability has become one of the main technical subjects for the TSV designs. However, criteria used for TSV reliability tests have not been consistent in the literature, so that the criterion itself becomes a technical argument. To this end, this paper first performed several different reliability tests on the testing packaging with TSV chains, then statistically analyzed the experimental data with different failure criteria on resistance increasing, and finally constructed the Weibull failure curves with parameter extractions. After comparing the results, it is suggested that using different criteria may lead to the same failure mode on Weibull analyses, and 65% of failed devices are recommended as a suitable termination for reliability tests.

  1. The temporal reliability of sound modulates visual detection: an event-related potential study.

    PubMed

    Li, Qi; Wu, Yan; Yang, Jingjing; Wu, Jinglong; Touge, Tetsuo

    2015-01-01

    Utilizing the high temporal resolution of event-related potentials (ERPs), we examined the effects of temporal reliability of sounds on visual detection. Significantly faster reaction times to visual target stimuli were observed when reliable temporal information was provided by a task-irrelevant auditory stimulus. Three main ERP components related to the effects of auditory temporal reliability were found: the first at 180-240 ms over a wide central area, the second at 300-400 ms over an anterior area, and the third at 300-380 ms over bilateral temporal areas. Our results support the hypothesis that temporal reliability affects visual detection and indicate that auditory facilitation of visual detection is partly due to spread of attention and thus results from implicit temporal linking of auditory and visual information at a relatively late processing stage.

  2. The Reliability and Validity of the Chinese Version of the Learning and Study Strategies Inventory (LASSI-C)

    ERIC Educational Resources Information Center

    Yip, Michael C. W.

    2013-01-01

    The Learning and Study Strategies Inventory (LASSI) is widely used in assessing students' learning and study strategies at both university and high school levels. The present study developed a Chinese version of LASSI (LASSI-C) and then further investigated the reliability, factor structure, and validity of LASSI-C scores, using a sample of 612…

  3. Reliability study of retention and memory gate integrity in a 1K MNOS RAM

    SciTech Connect

    Nasby, R.D.; Miller, W.M.; White, R.L.

    1986-01-01

    The reliability of a 1K MNOS RAM with regards to retention and nitride gate integrity has been demonstrated. Over 400 devices were screened and life tested to demonstrate 0.999 reliability during device life. The device was a 1K MNOS memory used in a RAM application with an erase/write cycle of 32 microseconds and a life specification of 1E7 cycles.

  4. The B-747 flight control system maintenance and reliability data base for cost effectiveness tradeoff studies

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Primary and automatic flight controls are combined for a total flight control reliability and maintenance cost data base using information from two previous reports and additional cost data gathered from a major airline. A comparison of the current B-747 flight control system effects on reliability and operating cost with that of a B-747 designed for an active control wing load alleviation system is provided.

  5. Psychometric instrumentation: reliability and validity of instruments used for clinical practice, evidence-based practice projects and research studies.

    PubMed

    Mayo, Ann M

    2015-01-01

    It is important for CNSs and other APNs to consider the reliability and validity of instruments chosen for clinical practice, evidence-based practice projects, or research studies. Psychometric testing uses specific research methods to evaluate the amount of error associated with any particular instrument. Reliability estimates explain more about how well the instrument is designed, whereas validity estimates explain more about scores that are produced by the instrument. An instrument may be architecturally sound overall (reliable), but the same instrument may not be valid. For example, if a specific group does not understand certain well-constructed items, then the instrument does not produce valid scores when used with that group. Many instrument developers may conduct reliability testing only once, yet continue validity testing in different populations over many years. All CNSs should be advocating for the use of reliable instruments that produce valid results. Clinical nurse specialists may find themselves in situations where reliability and validity estimates for some instruments that are being utilized are unknown. In such cases, CNSs should engage key stakeholders to sponsor nursing researchers to pursue this most important work.

  6. Study for Process Reliability Modeling and Controlling Method of Space Product

    NASA Astrophysics Data System (ADS)

    Hu, Xiao; Zhao, Changjian; Jia, Shengwei; Hong, Dongpao; Zhang, Xiaosai

    2016-07-01

    The inner collection between process reliability and stable process of space product is analysed, and the model of controlling-detecting process parameters is built by multiple linear regression technology. Then the extremum and mean value of multivariable controlling parameters' expected value, which meet the requirement of process detecting parameters' stability, are used to predict each mean response and new response, and also prediction ellipsoid and joint confidence intervals of detecting parameters are got. Furthermore, three optimization problems based on genetic algorithm, which focused on controlling parameters' fluctuation interval, are studied. Finally, space product ferrite phase shifter's coating is explained correctness of the method as a typical case. Thus, the significant guarantee is provided for improving space products' quality. Key words: process stability; multivariable linear model; predict; control 1)The original controlling range of detecting parameters[λ1a,λ2b] can be simplified as [a,b] , when k=λ1/λ2=1 , the best fluctuation interval of controlling parameters must be got on the symmetric interval for the linear process and weakly nonlinear process. 2)It can be inferred that controlling range of detecting parameters is asymmetric interval when k>1 and k<1 , the best fluctuation interval of controlling parameters must be got on the asymmetric interval for the nonlinear process. A. When the objective function is that 'the product of controlling parameters' fluctuation range is largest', the optimization model is...

  7. Reliability and validity of structural equation modeling applied to neuroimaging data: a simulation study.

    PubMed

    Boucard, Aurélie; Marchand, Alain; Noguès, Xavier

    2007-11-30

    Structural equation modeling aims at quantifying the strength of causal relationships within a set of interacting variables. Although the literature emphasizes that large sample sizes are required, this method is increasingly used with neuroimaging data of a limited number of subjects to study the relationships between cerebral structures. Here, we use a simulation approach to evaluate its ability to provide accurate information under the constraints of neuroimaging. Artificial samples representing the activity of a virtual set of structures were generated under both recursive and non-recursive connectivity models. Structural equation modeling was performed on these samples, and the quality of the analyses was evaluated by directly comparing the estimated path coefficients with the original ones. The validity and the reliability are shown to decrease with sample size, but the estimated models respect the relative strength of path coefficients in a large percentage of cases. The "smoothing method" appears to be the most appropriate to prevent improper solutions. Both the experimental error and the external structures influencing the network have a weak influence. Accordingly, structural equation modeling can be applied to neuroimaging data, but confidence intervals should be presented together with the path coefficient estimation.

  8. The biotron breeding system: a rapid and reliable procedure for genetic studies and breeding in rice.

    PubMed

    Ohnishi, Takayuki; Yoshino, Mihoko; Yamakawa, Hiromoto; Kinoshita, Tetsu

    2011-07-01

    Oryza sativa is widely used as a model organism for many aspects of research in monocots and cereals. However, it has certain disadvantages as a model species compared with Arabidopsis thaliana, the eudicot species most widely used in plant sciences: first, it has a long cultivation time; and second, it requires considerably more space for growth. Here, we introduce a biotron breeding system, which allows rapid and reliable rice cultivation using a well-equipped artificial environmental chamber. This system involves use of regulation of CO₂ levels, removal of tillers and embryo rescue to overcome the disadvantages of rice cultivation. The rice cultivars Nipponbare, Koshihikari, Taichung 65 and Kasalath all showed vigorous growth and sufficient seed production in the biotron breeding system with accelerated flowering time. Nipponbare, which was the earliest among these cultivars, flowered at about 50 d after sowing. The life cycle of these plants could be further shortened using an embryo rescue technique on immature seeds at 7 d after pollination, thereby avoiding the lengthy process of seed maturation. Overall, it was possible to shorten the life cycle of Nipponbare to about 2 months under the controlled conditions. Furthermore, controlled crosses, which can be difficult with conventional cultivation methods, were easy to perform as we could control the exact timing of anther dehiscence. Thus, our biotron breeding system offers a valuable new approach to genetic and breeding studies in rice.

  9. Systematic study of cell isolation from bovine nucleus pulposus: Improving cell yield and experiment reliability.

    PubMed

    Lee, Juliana T Y; Cheung, Kenneth M C; Leung, Victor Y L

    2015-12-01

    Differences in matrix compositions in human nucleus pulposus (NP) clinical samples demand different cell isolation protocols for optimal results but there is no clear guide about this to date. Sub-optimal protocols may result in low cell yield, limited reliability of results or even failure of experiments. Cell yield, viability and attachment of cells isolated from bovine NP tissue with different protocols were estimated by cell counting, Trypan blue staining and cell culturing respectively. RNA was extracted from isolated cells and quantified by Nanodrop spectrometry and RT-qPCR. Higher collagenase concentration, longer digestion duration and pronase pre-treatment increased the cell yield. Cell viability remained high (<5% dead cells) even after 0.2% collagenase treatment for overnight. NP cells remained to have high ACAN, COL2A1, CDH2, KRT18, and KRT19 expression compared to muscle cells for different cell isolation conditions tested. Digestion by collagenase alone without the use of pronase could isolate cells from human degenerated NP tissue but clusters of cells were observed. We suggest the use of the disappearance of tissue as an indirect measure of cells released. This study provides a guide for researchers to decide the parameters involved in NP cell isolation for optimal outcome.

  10. Selection of Reliable Reference Genes for Gene Expression Studies on Rhododendron molle G. Don

    PubMed Central

    Xiao, Zheng; Sun, Xiaobo; Liu, Xiaoqing; Li, Chang; He, Lisi; Chen, Shangping; Su, Jiale

    2016-01-01

    The quantitative real-time polymerase chain reaction (qRT-PCR) approach has become a widely used method to analyze expression patterns of target genes. The selection of an optimal reference gene is a prerequisite for the accurate normalization of gene expression in qRT-PCR. The present study constitutes the first systematic evaluation of potential reference genes in Rhododendron molle G. Don. Eleven candidate reference genes in different tissues and flowers at different developmental stages of R. molle were assessed using the following three software packages: GeNorm, NormFinder, and BestKeeper. The results showed that EF1-α (elongation factor 1-alpha), 18S (18s ribosomal RNA), and RPL3 (ribosomal protein L3) were the most stable reference genes in developing rhododendron flowers and, thus, in all of the tested samples, while tublin (TUB) was the least stable. ACT5 (actin), RPL3, 18S, and EF1-α were found to be the top four choices for different tissues, whereas TUB was not found to favor qRT-PCR normalization in these tissues. Three stable reference genes are recommended for the normalization of qRT-PCR data in R. molle. Furthermore, the expression profiles of RmPSY (phytoene synthase) and RmPDS (phytoene dehydrogenase) were assessed using EF1-α, 18S, ACT5, RPL3, and their combination as internals. Similar trends were found, but these trends varied when the least stable reference gene TUB was used. The results further prove that it is necessary to validate the stability of reference genes prior to their use for normalization under different experimental conditions. This study provides useful information for reliable qRT-PCR data normalization in gene studies of R. molle. PMID:27803707

  11. Tampa Scale of Kinesiophobia for Heart Turkish Version Study: cross-cultural adaptation, exploratory factor analysis, and reliability

    PubMed Central

    Acar, Serap; Savci, Sema; Keskinoğlu, Pembe; Akdeniz, Bahri; Özpelit, Ebru; Özcan Kahraman, Buse; Karadibak, Didem; Sevinc, Can

    2016-01-01

    Purpose Individuals with cardiac problems avoid physical activity and exercise because they expect to feel shortness of breath, dizziness, or chest pain. Assessing kinesiophobia related to heart problems is important in terms of cardiac rehabilitation. The Tampa Scale of Kinesiophobia Swedish Version for the Heart (TSK-SV Heart) is reliable and has been validated for cardiac diseases in the Swedish population. The aim of this study was to investigate the reliability, parallel-form validity, and exploratory factor analysis of the TSK for the Heart Turkish Version (TSK Heart Turkish Version) for evaluating kinesiophobia in patients with heart failure and pulmonary arterial hypertension. Methods This cross-sectional study involved translation, back translation, and cross-cultural adaptation (localization). Forty-three pulmonary arterial hypertension and 32 heart failure patients were evaluated using the TSK Heart Turkish Version. The 17-item scale, originally composed for the Swedish population, has four factors: perceived danger for heart problem, avoidance of exercise, fear of injury, and dysfunctional self. Cronbach’s alpha (internal consistency) and exploratory factor analysis were used to assess the questionnaire’s reliability. Results of the patients in the 6-minute walk test, International Physical Activity Questionnaire, and Nottingham Health Profile were analyzed by Pearson’s correlation analysis with the TSK Heart Turkish Version to indicate the convergent validity. Results Cronbach’s alpha for the TSK Heart Turkish Version was 0.75, indicating acceptable internal consistency. Although exploratory factor analysis showed a different subgroup distribution than the original questionnaire, the model was acceptable for the four-factor model hypothesis. Therefore, the questionnaire was rated as reliable. Conclusion These results supported the reliability of the TSK Heart Turkish Version. Since the acceptable four-factor model fits the subgroups and

  12. Fatigue and daytime sleepiness rating scales in myotonic dystrophy: a study of reliability

    PubMed Central

    Laberge, L; Gagnon, C; Jean, S; Mathieu, J

    2005-01-01

    Objectives: To assess the reliability of the Epworth Sleepiness Scale (ESS), Daytime Sleepiness Scale (DSS), Chalder Fatigue Scale (CFS), and Krupp's Fatigue Severity Scale (KFSS) in patients with myotonic dystrophy type 1 (DM1). Methods: In total, 27 patients with DM1 were administered the questionnaires on two occasions, with a 2 week interval. Internal consistency and test retest reliability were measured using intraclass correlation coefficients (ICCs), and Cronbach's α, Cohen's κ, and Goodman-Kruskal's γ coefficients. Results: Internal consistency of the CFS and KFSS were adequate (α>0.70) but that of the ESS was weak (α = 0.24). Both daytime sleepiness and fatigue rating scales showed significant test retest reliability. Test retest reliability for individual items revealed inconsistencies for some ESS and CFS items. Conclusions: Reliability of the CFS, DSS, and KFSS was high, allowing their use for individual patients with DM1, but that of the ESS was lower, rendering its current usage in DM1 questionable. Fatigue rating scales such as the KFSS, which are based on the behavioural consequences of fatigue, may constitute a more accurate and comprehensive measure of fatigue severity in the DM1 population. PMID:16170085

  13. An Examination of Coach and Player Relationships According to the Adapted LMX 7 Scale: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Caliskan, Gokhan

    2015-01-01

    The current study aims to test the reliability and validity of the Leader-Member Exchange (LMX 7) scale with regard to coach--player relationships in sports settings. A total of 330 professional soccer players from the Turkish Super League as well as from the First and Second Leagues participated in this study. Factor analyses were performed to…

  14. The Development of the Functional Literacy Experience Scale Based upon Ecological Theory (FLESBUET) and Validity-Reliability Study

    ERIC Educational Resources Information Center

    Özenç, Emine Gül; Dogan, M. Cihangir

    2014-01-01

    This study aims to perform a validity-reliability test by developing the Functional Literacy Experience Scale based upon Ecological Theory (FLESBUET) for primary education students. The study group includes 209 fifth grade students at Sabri Taskin Primary School in the Kartal District of Istanbul, Turkey during the 2010-2011 academic year.…

  15. Establishment of optimized MDCK cell lines for reliable efflux transport studies.

    PubMed

    Gartzke, Dominik; Fricker, Gert

    2014-04-01

    Madin-Darby canine kidney (MDCK) cells transfected with human MDR1 gene (MDCK-MDR1) encoding for P-glycoprotein (hPgp, ABCB1) are widely used for transport studies to identify drug candidates as substrates of this efflux protein. Therefore, it is necessary to rely on constant and comparable expression levels of Pgp to avoid false negative or positive results. We generated a cell line with homogenously high and stable expression of hPgp through sorting single clones from a MDCK-MDR1 cell pool using fluorescence-activated cell sorting (FACS). To obtain control cell lines for evaluation of cross-interactions with endogenous canine Pgp (cPgp) wild-type cells were sorted with a low expression pattern of cPgp in comparison with the MDCK-MDR1. Expression of other transporters was also characterized in both cell lines by quantitative real-time PCR and Western blot. Pgp function was investigated applying the Calcein-AM assay as well as bidirectional transport assays using (3) H-Digoxin, (3) H-Vinblastine, and (3) H-Quinidine as substrates. Generated MDCK-MDR1 cell lines showed high expression of hPgp. Control MDCK-WT cells were optimized in showing a comparable expression level of cPgp in comparison with MDCK-MDR1 cell lines. Generated cell lines showed higher and more selective Pgp transport compared with parental cells. Therefore, they provide a significant improvement in the performance of efflux studies yielding more reliable results.

  16. The spatial reliability of task-irrelevant sounds modulates bimodal audiovisual integration: An event-related potential study.

    PubMed

    Li, Qi; Yu, Hongtao; Wu, Yan; Gao, Ning

    2016-08-26

    The integration of multiple sensory inputs is essential for perception of the external world. The spatial factor is a fundamental property of multisensory audiovisual integration. Previous studies of the spatial constraints on bimodal audiovisual integration have mainly focused on the spatial congruity of audiovisual information. However, the effect of spatial reliability within audiovisual information on bimodal audiovisual integration remains unclear. In this study, we used event-related potentials (ERPs) to examine the effect of spatial reliability of task-irrelevant sounds on audiovisual integration. Three relevant ERP components emerged: the first at 140-200ms over a wide central area, the second at 280-320ms over the fronto-central area, and a third at 380-440ms over the parieto-occipital area. Our results demonstrate that ERP amplitudes elicited by audiovisual stimuli with reliable spatial relationships are larger than those elicited by stimuli with inconsistent spatial relationships. In addition, we hypothesized that spatial reliability within an audiovisual stimulus enhances feedback projections to the primary visual cortex from multisensory integration regions. Overall, our findings suggest that the spatial linking of visual and auditory information depends on spatial reliability within an audiovisual stimulus and occurs at a relatively late stage of processing.

  17. Cost and reliability study for a large array of small reflector antennas for JPL/NASA Deep Space Network (DSN)

    NASA Technical Reports Server (NTRS)

    Jamnejad, Vahraz; Cwik, Tom; Resch, George

    1993-01-01

    A study performed to estimate the cost of an array of small aperture reflector antennas to be used instead of or in conjunction with the current large reflector antennas of the JPL/NASA Deep Space Network (DSN) is described. The arrays are used for servicing present and future NASA missions that involve smaller spacecraft with limited power and smaller, lower-gain antennas. The advantages of the array configuration in terms of cost and reliability are discussed. A probabilistic determination of the reliability and availability of the array as a function of the number of array elements and the availability of individual array elements is made. The impact of additional marginal elements on the operational availability of the array is studied. Parametric cost and reliability plots are presented and directions for further investigation are outlined.

  18. Reliability of a novel neurostimulation method to study involuntary muscle phenomena.

    PubMed

    Minetto, Marco Alessandro; Botter, Alberto; Ravenni, Roberta; Merletti, Roberto; De Grandis, Domenico

    2008-01-01

    Experimental methods involving painful electrical stimulation of a peripheral nerve showed the existence of a minimum stimulation frequency capable of inducing cramp, termed "threshold frequency" (TF). Our aim was to test an alternative method to induce fasciculations and cramps electrically. Two daily sessions of electrical stimulation of the abductor hallucis muscle were performed in 19 volunteers on 3 days: stimulation trains of 150 monophasic square pulses (duration 152 micros) of increasing frequency (current intensity 30% higher than maximal; frequency of the first trial, 4 pps; recovery between trials, 1 min) were delivered to the main muscle motor point until a cramp developed. Once a cramp was induced the protocol was repeated after 30 min. To verify by electromyography that cramp occurred, a surface electrode array was placed between the motor point and the distal tendon. Ambient and skin temperature were kept constant in all sessions. Fasciculations and cramps were elicited in all subjects. We observed the following median (interquartile range) values of TF: day 1 (session 1), 13 (6) pps; day 1 (session 2), 16 (4) pps; day 2 (session 1), 16 (6) pps; day 2 (session 2), 18 (6) pps; day 3 (session 1), 17 (4) pps; day 3 (session 2), 18 (8) pps. TF intersession intraclass correlation coefficients were 0.82, 0.92, and 0.90 for days 1, 2, and 3, respectively. TF interday intraclass correlation coefficient was 0.85. The absence of pain due to the stimulation and the demonstration of TF reliability support the use of our method for the study of involuntary muscle phenomena.

  19. ELISA for thyroglobulin in serum: recovery studies to evaluate autoantibody interference and reliability of thyroglobulin values.

    PubMed

    Erali, M; Bigelow, R B; Meikle, A W

    1996-05-01

    An ELISA for measuring thyroglobulin (Tg) in serum was developed with polyclonal antibodies to Tg on the solid phase and two monoclonal antibodies to Tg as the second antibodies. The assay has a detection limit of 1 microgram/L, a within-run imprecision (CV) of <7%, and a between-run CV of < 10%. Parallelism of the assay was shown in dilution studies, in which the percent observed/expected values for n = 5 autoantibody-containing samples gave a mean of 99% (SD 13.1 %); for n = 5 samples with undetectable autoantibody concentrations, the mean was 103% (SD 11.8%). The correlation of the ELISA with an RIA for Tg in 46 normal samples was ELISA = 1.11(RIA) + 0.52, S y/x = 2.23, SD intercept = 0.54, SD slope = 0.03, range = 0 to 53 micrograms/L, r = 0.980. Comparison of the ELISA with a reference laboratory RIA for 29 clinical samples gave a correlation of: ELISA = 1.53(RIA) - 0.48, S y/x = 9.00, SD intercept = 2.19, SD slope = 0.10, range = 0 to 98 micrograms/L, r = 0.950. To provide additional information concerning the reliability of the Tg measurement in samples containing autoantibodies to Tg, we developed a procedure for determining the percent recovery. A percent recovery greater than or equal to 80% indicates minimal interference by autoantibodies in this assay. The assay is straightforward to perform, results can be posted within 8 h, and the routinely good recovery of Tg in the presence of Tg autoantibodies indicates minimal autoantibody interference in this assay.

  20. Salivary cortisol protocol adherence and reliability by socio-demographic features: the Multi-Ethnic Study of Atherosclerosis.

    PubMed

    Hill Golden, Sherita; Sánchez, Brisa N; Desantis, Amy S; Wu, Meihua; Castro, Cecilia; Seeman, Teresa E; Tadros, Sameh; Shrager, Sandi; Diez Roux, Ana V

    2014-05-01

    Collection of salivary cortisol has become increasingly popular in large population-based studies. However, the impact of protocol compliance on day-to-day reliabilities of measures, and the extent to which reliabilities differ systematically according to socio-demographic characteristics, has not been well characterized in large-scale population-based studies to date. Using data on 935 men and women from the Multi-Ethnic Study of Atherosclerosis, we investigated whether sampling protocol compliance differs systematically according to socio-demographic factors and whether compliance was associated with cortisol estimates, as well as whether associations of cortisol with both compliance and socio-demographic characteristics were robust to adjustments for one another. We further assessed the day-to-day reliability for cortisol features and the extent to which reliabilities vary according to socio-demographic factors and sampling protocol compliance. Overall, we found higher compliance among persons with higher levels of income and education. Lower compliance was significantly associated with a less pronounced cortisol awakening response (CAR) but was not associated with any other cortisol features, and adjustment for compliance did not affect associations of socio-demographic characteristics with cortisol. Reliability was higher for area under the curve (AUC) and wake up values than for other features, but generally did not vary according to socio-demographic characteristics, with few exceptions. Our findings regarding intra-class correlation coefficients (ICCs) support prior research indicating that multiple day collection is preferable to single day collection, particularly for CAR and slopes, more so than wakeup and AUC. There were few differences in reliability by socio-demographic characteristics. Thus, it is unlikely that group-specific sampling protocols are warranted.

  1. A reliability study using computer-based analysis of finger joint space narrowing in rheumatoid arthritis patients.

    PubMed

    Hatano, Katsuya; Kamishima, Tamotsu; Sutherland, Kenneth; Kato, Masaru; Nakagawa, Ikuma; Ichikawa, Shota; Kawauchi, Keisuke; Saitou, Shota; Mukai, Masaya

    2017-02-01

    The joint space difference index (JSDI) is a newly developed radiographic index which can quantitatively assess joint space narrowing progression of rheumatoid arthritis (RA) patients by using an image subtraction method on a computer. The aim of this study was to investigate the reliability of this method by non-experts utilizing RA image evaluation. Four non-experts assessed JSDI for radiographic images of 510 metacarpophalangeal joints from 51 RA patients twice with an interval of more than 2 weeks. Two rheumatologists and one radiologist as well as the four non-experts examined the joints by using the Sharp-van der Heijde Scoring (SHS) method. The radiologist and four non-experts repeated the scoring with an interval of more than 2 weeks. We calculated intra-/inter-observer reliability using the intra-class correlation coefficients (ICC) for JSDI and SHS scoring, respectively. The intra-/inter-observer reliabilities for the computer-based method were almost perfect (inter-observer ICC, 0.966-0.983; intra-observer ICC, 0.954-0.996). Contrary to this, intra-/inter-observer reliability for SHS by experts was moderate to almost perfect (inter-observer ICC, 0.556-0.849; intra-observer ICC, 0.589-0.839). The results suggest that our computer-based method has high reliability to detect finger joint space narrowing progression in RA patients.

  2. A Laboratory Study on the Reliability Estimations of the Mini-CEX

    ERIC Educational Resources Information Center

    de Lima, Alberto Alves; Conde, Diego; Costabel, Juan; Corso, Juan; Van der Vleuten, Cees

    2013-01-01

    Reliability estimations of workplace-based assessments with the mini-CEX are typically based on real-life data. Estimations are based on the assumption of local independence: the object of the measurement should not be influenced by the measurement itself and samples should be completely independent. This is difficult to achieve. Furthermore, the…

  3. A Validity and Reliability Study of the Attitudes toward Sustainable Development Scale

    ERIC Educational Resources Information Center

    Biasutti, Michele; Frate, Sara

    2017-01-01

    This article describes the development and validation of the Attitudes toward Sustainable Development scale, a quantitative 20-item scale that measures Italian university students' attitudes toward sustainable development. A total of 484 undergraduate students completed the questionnaire. The validity and reliability of the scale was statistically…

  4. Educational Management Organizations as High Reliability Organizations: A Study of Victory's Philadelphia High School Reform Work

    ERIC Educational Resources Information Center

    Thomas, David E.

    2013-01-01

    This executive position paper proposes recommendations for designing reform models between public and private sectors dedicated to improving school reform work in low performing urban high schools. It reviews scholarly research about for-profit educational management organizations, high reliability organizations, American high school reform, and…

  5. Assessing Academic Advising Outcomes Using Social Cognitive Theory: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Erlich, Richard J.; Russ-Eft, Darlene F.

    2012-01-01

    The validity and reliability of three instruments, the "Counselor Rubric for Gauging Student Understanding of Academic Planning," micro-analytic questions, and the "Student Survey for Understanding Academic Planning," all based on social cognitive theory, were tested as means to assess self-efficacy and self-regulated learning in college academic…

  6. Observation and Classification of Prehension in Preschool Children: A Reliability Study.

    ERIC Educational Resources Information Center

    Moss, S. C.; Hogg, J.

    1981-01-01

    The variety of hand grips of 12 children, most of whom were moderately or severely retarded, were classified in order to begin an analysis of hand function. Test reliability was not as great when items were presented to the children as compared to when children were observed or rated by videotape. (FG)

  7. Six Single-Administration Reliability Coefficients for Criterion-Referenced Tests: A Comparative Study.

    ERIC Educational Resources Information Center

    Downing, Steven M.; Mehrens, William A.

    Four criterion-referenced reliability coefficicents were compared to the Kuder-Richardson estimates and to each other. The Kuder-Richardson formulas 20 and 21, the Livingston, the Subkoviak and two Huynh coefficients were computed for a random sample of 33 criterion-referenced tests. The Subkoviak coefficient yielded the highest mean value;…

  8. Lifelong Learning Competence Scale (LLLCS): The Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Uzunboylu, Huseyin; Hursen, Cigdem

    2011-01-01

    In this research our aim is to develop a scale for lifelong learning competences and investigate the validity and the reliability of the structure of the scale. The participants of this research are 300 secondary school teachers who are randomly selected. The findings on the scale's validity of the structure are computed by the method of factor…

  9. Reliability and norms for the 10-item self-motivation inventory: The TIGER Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Self-Motivation Inventory (SMI) has been shown to be a predictor of exercise dropout. The original SMI of 40 items has been shortened to 10 items and the psychometric qualities of the 10-item SMI are not known. To estimate the reliability of a 10-item SMI and develop norms for an ethnically dive...

  10. Spinal palpatory diagnostic procedures utilized by practitioners of spinal manipulation: annotated bibliography of content validity and reliability studies

    PubMed Central

    Seffinger, Michael; Adams, Alan; Najm, Wadie; Dickerson, Vivian; Mishra, Shiraz I; Reinsch, Sibylle; Murphy, Linda

    2003-01-01

    The diagnosis of spinal neuro-musculoskeletal dysfunction is a pre-requisite for application of spinal manual therapy. Different disciplines rely on palpatory procedures to establish this diagnosis and design treatment plans. Over the past 30 years, the osteopathic, chiropractic, physical therapy and allopathic professions have investigated the validity and reliability of spinal palpatory procedures. We explored the literature from all four disciplines looking for scientific papers studying the content validity and reliability of spinal palpatory procedures. Thirteen databases were searched for relevant papers between January 1966 and October 2001. An annotated bibliography of these articles is presented and organized by the type of test used.

  11. Space Shuttle Rudder Speed Brake Actuator-A Case Study Probabilistic Fatigue Life and Reliability Analysis

    NASA Technical Reports Server (NTRS)

    Oswald, Fred B.; Savage, Michael; Zaretsky, Erwin V.

    2015-01-01

    The U.S. Space Shuttle fleet was originally intended to have a life of 100 flights for each vehicle, lasting over a 10-year period, with minimal scheduled maintenance or inspection. The first space shuttle flight was that of the Space Shuttle Columbia (OV-102), launched April 12, 1981. The disaster that destroyed Columbia occurred on its 28th flight, February 1, 2003, nearly 22 years after its first launch. In order to minimize risk of losing another Space Shuttle, a probabilistic life and reliability analysis was conducted for the Space Shuttle rudder/speed brake actuators to determine the number of flights the actuators could sustain. A life and reliability assessment of the actuator gears was performed in two stages: a contact stress fatigue model and a gear tooth bending fatigue model. For the contact stress analysis, the Lundberg-Palmgren bearing life theory was expanded to include gear-surface pitting for the actuator as a system. The mission spectrum of the Space Shuttle rudder/speed brake actuator was combined into equivalent effective hinge moment loads including an actuator input preload for the contact stress fatigue and tooth bending fatigue models. Gear system reliabilities are reported for both models and their combination. Reliability of the actuator bearings was analyzed separately, based on data provided by the actuator manufacturer. As a result of the analysis, the reliability of one half of a single actuator was calculated to be 98.6 percent for 12 flights. Accordingly, each actuator was subsequently limited to 12 flights before removal from service in the Space Shuttle.

  12. Test-retest reliability of graph metrics in functional brain networks: a resting-state fNIRS study.

    PubMed

    Niu, Haijing; Li, Zhen; Liao, Xuhong; Wang, Jinhui; Zhao, Tengda; Shu, Ni; Zhao, Xiaohu; He, Yong

    2013-01-01

    Recent research has demonstrated the feasibility of combining functional near-infrared spectroscopy (fNIRS) and graph theory approaches to explore the topological attributes of human brain networks. However, the test-retest (TRT) reliability of the application of graph metrics to these networks remains to be elucidated. Here, we used resting-state fNIRS and a graph-theoretical approach to systematically address TRT reliability as it applies to various features of human brain networks, including functional connectivity, global network metrics and regional nodal centrality metrics. Eighteen subjects participated in two resting-state fNIRS scan sessions held ∼20 min apart. Functional brain networks were constructed for each subject by computing temporal correlations on three types of hemoglobin concentration information (HbO, HbR, and HbT). This was followed by a graph-theoretical analysis, and then an intraclass correlation coefficient (ICC) was further applied to quantify the TRT reliability of each network metric. We observed that a large proportion of resting-state functional connections (∼90%) exhibited good reliability (0.6< ICC <0.74). For global and nodal measures, reliability was generally threshold-sensitive and varied among both network metrics and hemoglobin concentration signals. Specifically, the majority of global metrics exhibited fair to excellent reliability, with notably higher ICC values for the clustering coefficient (HbO: 0.76; HbR: 0.78; HbT: 0.53) and global efficiency (HbO: 0.76; HbR: 0.70; HbT: 0.78). Similarly, both nodal degree and efficiency measures also showed fair to excellent reliability across nodes (degree: 0.52∼0.84; efficiency: 0.50∼0.84); reliability was concordant across HbO, HbR and HbT and was significantly higher than that of nodal betweenness (0.28∼0.68). Together, our results suggest that most graph-theoretical network metrics derived from fNIRS are TRT reliable and can be used effectively for brain network

  13. The Six-Minute Walk Test for Adults with Intellectual Disability: A Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Nasuti, Gabriella; Stuart-Hill, Lynneth; Temple, Viviene A.

    2013-01-01

    Background: The Six-Minute Walk Test (6MWT) has been used with clinical and healthy populations to assess functional capacity and cardiovascular fitness. The aim of this study was to determine the test-retest reliability of a modified-6MWT as well as concurrent validity of walk distance with peak oxygen uptake (VO[subscript 2] peak). Method:…

  14. A Validation Study of the Dutch Childhood Trauma Questionnaire-Short Form: Factor Structure, Reliability, and Known-Groups Validity

    ERIC Educational Resources Information Center

    Thombs, Brett D.; Bernstein, David P.; Lobbestael, Jill; Arntz, Arnoud

    2009-01-01

    Objective: The 28-item Childhood Trauma Questionnaire-Short Form (CTQ-SF) has been translated into at least 10 different languages. The validity of translated versions of the CTQ-SF, however, has generally not been examined. The objective of this study was to investigate the factor structure, internal consistency reliability, and known-groups…

  15. Testing the reliability and validity of computer-mediated social support measures among older adults: a pilot study.

    PubMed

    Nahm, Eun-Shim; Resnick, Barbara; Gaines, Jean

    2004-01-01

    With the increasing number of older adult online users, the Internet and e-mail are becoming a new source of social support for older adults. To assess this computer-mediated social support, two traditional social support measures were modified: (1) the Lubben Social Network Scale and (2) the Medical Outcomes Study Social Support Survey. The purpose of this pilot study was to test the reliability and validity of these modified measures. This study was a single group descriptive study with two data collection points. Data were collected using Web surveys. A total of 38 older adult participants completed the first survey; 35, the second survey. The findings of this preliminary study provided evidence for the reliability, content validity, and, to a limited extent, construct validity, of the modified measures. Additional studies with a larger representative sample are needed to further examine the psychometric aspects of these measures.

  16. Health measurement using the ICF: Test-retest reliability study of ICF codes and qualifiers in geriatric care

    PubMed Central

    Okochi, Jiro; Utsunomiya, Sakiko; Takahashi, Tai

    2005-01-01

    Background The International Classification of Functioning, Disability and Health (ICF) was published by the World Health Organization (WHO) to standardize descriptions of health and disability. Little is known about the reliability and clinical relevance of measurements using the ICF and its qualifiers. This study examines the test-retest reliability of ICF codes, and the rate of immeasurability in long-term care settings of the elderly to evaluate the clinical applicability of the ICF and its qualifiers, and the ICF checklist. Methods Reliability of 85 body function (BF) items and 152 activity and participation (AP) items of the ICF was studied using a test-retest procedure with a sample of 742 elderly persons from 59 institutional and at home care service centers. Test-retest reliability was estimated using the weighted kappa statistic. The clinical relevance of the ICF was estimated by calculating immeasurability rate. The effect of the measurement settings and evaluators' experience was analyzed by stratification of these variables. The properties of each item were evaluated using both the kappa statistic and immeasurability rate to assess the clinical applicability of WHO's ICF checklist in the elderly care setting. Results The median of the weighted kappa statistics of 85 BF and 152 AP items were 0.46 and 0.55 respectively. The reproducibility statistics improved when the measurements were performed by experienced evaluators. Some chapters such as genitourinary and reproductive functions in the BF domain and major life area in the AP domain contained more items with lower test-retest reliability measures and rated as immeasurable than in the other chapters. Some items in the ICF checklist were rated as unreliable and immeasurable. Conclusion The reliability of the ICF codes when measured with the current ICF qualifiers is relatively low. The result in increase in reliability according to evaluators' experience suggests proper education will have positive

  17. Livingston's Reliability Coefficient and Harris' Index of Efficiency: An Empirical Study of the Two Reliability Coefficients For Criterion-Referenced Tests.

    ERIC Educational Resources Information Center

    Rim, Eui-Do; Bresler, Samuel

    Livingston's reliability coefficients and Harris' indices of efficiency were computed along with the classical internal consistency coefficients, KR-20's (Kuder-Richardson internal consistency coefficient), for 678 criterion-referenced tests in the A through E levels of an individualized mathematics program. The coefficients were carefully studied…

  18. Reliability of distance estimation by doctors and patients: cross sectional study.

    PubMed Central

    Sharrack, B.; Hughes, R. A.

    1997-01-01

    OBJECTIVE: To assess the reliability and accuracy of distance estimated by doctors and patients. DESIGN: Comparison between estimated and measured distances of six familiar sites around Guy's Hospital, London. SUBJECTS: 100 hospital consultants and 100 patients. MAIN OUTCOME MEASURES: Median (range) of estimated distances, and mean (SD) of the difference between estimated and measured distances. RESULTS: Both doctors and patients gave a wide range of estimates of distance. The estimates differed by up to 14.6-fold from the measured distances, and the difference between minimum and maximum estimates was up to 62.5-fold. CONCLUSION: Doctors and patients were inaccurate at estimating distances, which implies that estimates of distances walked are not reliable indicators of a person's health. PMID:9448528

  19. Missile and Space Systems Reliability versus Cost Trade-Off Study

    DTIC Science & Technology

    1983-01-01

    account for nonlinearities and the readiness requirement scored as (1) for present or (0) for not present. 53 0’ 11- TABLE 3-12 -PROGRAM/SYSTEM...implementing an acceptable reliability progam . While only 10% felt that improper tailoring was at fault, an equally divided response of 37Z each felt the...account for a strong nonlinear influence due to program phase. A more rigorous investigation would use a phase-by-phase analysis of the data, but the

  20. The reliability of in-home measures of height and weight in large cohort studies: Evidence from Add Health

    PubMed Central

    Hussey, Jon M.; Nguyen, Quynh C.; Whitsel, Eric A.; Richardson, Liana J.; Halpern, Carolyn Tucker; Gordon-Larsen, Penny; Tabor, Joyce W.; Entzel, Pamela P.; Harris, Kathleen Mullan

    2015-01-01

    Background With the emergence of obesity as a global health issue an increasing number of major demographic surveys are collecting measured anthropometric data. Yet little is known about the characteristics and reliability of these data. Objectives We evaluate the accuracy and reliability of anthropometric data collected in the home during Wave IV of the National Longitudinal Study of Adolescent to Adult Health (Add Health), compare our estimates to national standard, clinic-based estimates from the National Health and Nutrition Examination Survey (NHANES) and, using both sources, provide a detailed anthropometric description of young adults in the United States. Methods The reliability of Add Health in-home anthropometric measures was estimated from repeat examinations of a random subsample of study participants. A digit preference analysis evaluated the quality of anthropometric data recorded by field interviewers. The adjusted odds of obesity and central obesity in Add Health vs. NHANES were estimated with logistic regression. Results Short-term reliabilities of in-home measures of height, weight, waist and arm circumference—as well as derived body mass index (BMI, kg/m2)—were excellent. Prevalence of obesity (37% vs. 29%) and central obesity (47% vs. 38%) was higher in Add Health than in NHANES while socio-demographic patterns of obesity and central obesity were comparable in the two studies. Conclusions Properly trained non-medical field interviewers can collect reliable anthropometric data in a nationwide, home visit study. This national cohort of young adults in the United States faces a high risk of early-onset chronic disease and premature mortality. PMID:26146486

  1. Failure Analysis Study and Long-Term Reliability of Optical Assemblies with End-Face Damage

    NASA Technical Reports Server (NTRS)

    Kichak, Robert A.; Ott, Melanie N.; Leidecker, Henning W.; Chuska, Richard F.; Greenwell, Christopher J.

    2008-01-01

    In June 2005, the NESC received a multi-faceted request to determine the long term reliability of fiber optic termini on the ISS that exhibited flaws not manufactured to best workmanship practices. There was a lack of data related to fiber optic workmanship as it affects the long term reliability of optical fiber assemblies in a harsh environment. A fiber optic defect analysis was requested which would find and/or create various types of chips, spalls, scratches, etc., that were identified by the ISS personnel. Once the defects and causes were identified the next step would be to perform long term reliability testing of similar assemblies with similar defects. The goal of the defect analysis would be for the defects to be observed and documented for deterioration of fiber optic performance. Though this report mostly discusses what has been determined as evidence of poor manufacturing processes, it also concludes the majority of the damage could have been avoided with a rigorous process in place.

  2. The Child Attachment Interview: a psychometric study of reliability and discriminant validity.

    PubMed

    Shmueli-Goetz, Yael; Target, Mary; Fonagy, Peter; Datta, Adrian

    2008-07-01

    While well-established attachment measures have been developed for infancy, early childhood, and adulthood, a "measurement gap" has been identified in middle childhood, where behavioral or representational measures are not yet sufficiently robust. This article documents the development of a new measure--the Child Attachment Interview (CAI)--which seeks to bridge this gap. The CAI is a semistructured interview, in which children are invited to describe their relationships with their primary caregivers. The coding system is informed by the Adult Attachment Interview and the Strange Situation Procedure, and produces 4 attachment categories along with a continuous measure of attachment security based on ratings of attachment-related dimensions. The main psychometric properties are presented, including interrater reliability, test-retest reliability, and concurrent and discriminant validities, both for normally developing children and for those referred for mental health treatment. The CAI correlates as expected with other attachment measures and predicts independently collected ratings of social functioning. The findings suggest that the CAI is a reliable, valid, and promising measure of child-parent attachment in middle childhood. Directions for improvements to the coding system are discussed.

  3. A case study of reliability ensemble averaging for terrestrial biosphere simulators

    NASA Astrophysics Data System (ADS)

    Schwalm, C. R.; Huntzinger, D. N.; Fisher, J. B.; Liu, J.; Bowman, K. W.; Block, G.; Sikka, M.

    2013-12-01

    Reliability ensemble averaging (REA) is a procedure used to derive a multi-model mean that is not based on 'one model - one vote'. Instead, REA is based on confronting each member of the ensemble with defined references to gauge model skill. These skill values are then transformed to weights or reliability factors. Here we apply REA to a 10-model ensemble to generate a net ecosystem exchange (NEE) prior for NASA's Carbon Monitoring System. The ensemble is taken from the Multi-Scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP), an excellent opportunity to derive and apply weighting procedures to terrestrial biosphere models (TBMs) due to its constrained protocol. All models use a standardized driver data suite and spinup conditions; only model structure is allowed to vary such that the weights are not confounded by other factors. We find there are few land grid cells (<1%) where 'one model - one vote' is appropriate. Reliability factors vary widely and display spatial relationships across models; some of these appear random whereas others correspond to ecoregions and ecotones. There is less change in weights through time; models are more consistent in time than space. Despite this clear departure from 'one model - one vote' global aggregates of the weighted NEE prior are in close agreement with the unweighted version.

  4. Person Reliability

    ERIC Educational Resources Information Center

    Lumsden, James

    1977-01-01

    Person changes can be of three kinds: developmental trends, swells, and tremors. Person unreliability in the tremor sense (momentary fluctuations) can be estimated from person characteristic curves. Average person reliability for groups can be compared from item characteristic curves. (Author)

  5. Another Alternative: A 90-Day Contractual Detoxification Treatment Program

    ERIC Educational Resources Information Center

    Kahn, Robert B.; And Others

    1978-01-01

    In May 1974, Fresno County's Narcotic Abuse Treatment Program began a 21-day outpatient methadone detoxification treatment modality. The purpose of this paper is to examine this alternative treatment modality, its characteristics, its therapeutic outcomes and the rationale for its use. (Author)

  6. 40 CFR 799.9325 - TSCA 90-day dermal toxicity.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...—adrenals, parathyroid, thyroid. (D) Respiratory system—trachea, lungs, pharynx, larynx, nose. (E..., but not be limited to, evaluation of skin and fur, eyes and mucous membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system effects, including...

  7. 40 CFR 799.9325 - TSCA 90-day dermal toxicity.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...—adrenals, parathyroid, thyroid. (D) Respiratory system—trachea, lungs, pharynx, larynx, nose. (E..., but not be limited to, evaluation of skin and fur, eyes and mucous membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system effects, including...

  8. 40 CFR 799.9325 - TSCA 90-day dermal toxicity.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...—adrenals, parathyroid, thyroid. (D) Respiratory system—trachea, lungs, pharynx, larynx, nose. (E..., but not be limited to, evaluation of skin and fur, eyes and mucous membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system effects, including...

  9. 40 CFR 799.9346 - TSCA 90-day inhalation toxicity.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system...) Thyroids. (D) Respiratory system. (1) Trachea. (2) Lung. (3) Pharynx. (4) Larynx. (5) Nose. (E..., whatever its size, shape, and density. It is used to predict where in the respiratory tract such...

  10. 40 CFR 799.9325 - TSCA 90-day dermal toxicity.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...—adrenals, parathyroid, thyroid. (D) Respiratory system—trachea, lungs, pharynx, larynx, nose. (E..., but not be limited to, evaluation of skin and fur, eyes and mucous membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system effects, including...

  11. 40 CFR 799.9346 - TSCA 90-day inhalation toxicity.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system...) Thyroids. (D) Respiratory system. (1) Trachea. (2) Lung. (3) Pharynx. (4) Larynx. (5) Nose. (E..., whatever its size, shape, and density. It is used to predict where in the respiratory tract such...

  12. 40 CFR 799.9325 - TSCA 90-day dermal toxicity.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...—adrenals, parathyroid, thyroid. (D) Respiratory system—trachea, lungs, pharynx, larynx, nose. (E..., but not be limited to, evaluation of skin and fur, eyes and mucous membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system effects, including...

  13. 40 CFR 799.9346 - TSCA 90-day inhalation toxicity.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system...) Thyroids. (D) Respiratory system. (1) Trachea. (2) Lung. (3) Pharynx. (4) Larynx. (5) Nose. (E..., whatever its size, shape, and density. It is used to predict where in the respiratory tract such...

  14. 40 CFR 799.9346 - TSCA 90-day inhalation toxicity.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system...) Thyroids. (D) Respiratory system. (1) Trachea. (2) Lung. (3) Pharynx. (4) Larynx. (5) Nose. (E..., whatever its size, shape, and density. It is used to predict where in the respiratory tract such...

  15. 40 CFR 799.9346 - TSCA 90-day inhalation toxicity.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... membranes, respiratory and circulatory effects, autonomic effects such as salivation, central nervous system...) Thyroids. (D) Respiratory system. (1) Trachea. (2) Lung. (3) Pharynx. (4) Larynx. (5) Nose. (E..., whatever its size, shape, and density. It is used to predict where in the respiratory tract such...

  16. Test effectiveness study report: An analytical study of system test effectiveness and reliability growth of three commercial spacecraft programs

    NASA Technical Reports Server (NTRS)

    Feldstein, J. F.

    1977-01-01

    Failure data from 16 commercial spacecraft were analyzed to evaluate failure trends, reliability growth, and effectiveness of tests. It was shown that the test programs were highly effective in ensuring a high level of in-orbit reliability. There was only a single catastrophic problem in 44 years of in-orbit operation on 12 spacecraft. The results also indicate that in-orbit failure rates are highly correlated with unit and systems test failure rates. The data suggest that test effectiveness estimates can be used to guide the content of a test program to ensure that in-orbit reliability goals are achieved.

  17. Predictability and Reliability of Different Anterio-Posterior Skeletal Discrepancy Indicators in Different Age Groups - A Cephalometric Study

    PubMed Central

    Tiwari, Rana; Gupta, Abhishek; Joshi, Rishi; Tiwari, Anil; Sen, Priyank

    2016-01-01

    Introduction The lateral cephalometric skeletal discrepancy indicators play a major role in diagnosing and preparing a case for orthognathic surgeries and the dentofacial corrections. Aim The study was aimed to check the reliability and the predictability of different anterio-posterior skeletal discrepancy indicators in different age groups and to derive the most reliable indicator for the orthodontic diagnosis. Materials and Methods A cross-sectional study was conducted on a sample of 100 subjects including 29 adolescent (15 males and 14 females) and 71 adult (41 males and 30 females) subjects with the mean age of 19.05 ± 5.78 years. All the subjects had Angle’s Class I molar relationship. The lateral cephalograms of the sample were taken under the standard setting and hand tracing of the cephalometric radiographs using a sharp 4H pencil were made on acetate tracing paper. The anterio-posterior cephalometric indicators like β-angle, Wits appraisal (mm), Sella- Nasion plane to Point A and Point B distance (SN-AB mm) and Maxillo-Mandibular plane angle bisector to Point A and Point B distance (MM-AB mm) were measured. Intra-examiner reliability of tracings was evaluated using Intra Class Correlation (ICC) test. Mann Whitney U-test was applied for comparison of parameters between different malocclusion groups. Concurrent validity of various parameters was calculated using Cohen’s kappa. A p-value <0.05 was considered statistically significant. Results The comparison of intra-examiner reliability of tracings in Angle’s Class I adolescent group showed, MM-AB to have an almost perfect agreement followed by Wits. Intra-examiner reliability of tracings in Angle’s Class I adult group showed moderate agreement for Wits and MM-AB showed almost perfect agreement and all the parameters showed statistically significant ICC. Comparison of parameters between adolescent and adult, Angle’s Class I malocclusion group showed significant difference between adolescent and

  18. Assessing Households Preparedness for Earthquakes: An Exploratory Study in the Development of a Valid and Reliable Persian-version Tool

    PubMed Central

    Ardalan, Ali; Sohrabizadeh, Sanaz

    2016-01-01

    Introduction: Iran is placed among countries suffering from the highest number of earthquake casualties. Household preparedness, as one component of risk reduction efforts, is often supported in quake-prone areas. In Iran, lack of a valid and reliable household preparedness tool was reported by previous disaster studies. This study is aimed to fill this gap by developing a valid and reliable tool for assessing household preparedness in the event of an earthquake. Methods: This survey was conducted through three phases including literature review and focus group discussions with the participation of eight key informants, validity measurements and reliability measurements. Field investigation was completed with the participation of 450 households within three provinces of Iran. Content validity, construct validity, the use of factor analysis; internal consistency using Cronbach's alpha coefficient, and test-retest reliability were carried out to develop the tool. Results: Based on the CVIs, ranging from 0.80 to 0.100, and exploratory factor analysis with factor loading of more than 0.5, all items were valid. The amount of Cronbach's alpha (0.7) and test-retest examination by Spearman correlations indicated that the scale was also reliable. The final instrument consisted of six categories and 18 questions including actions at the time of earthquakes, nonstructural safety, structural safety, hazard map, communications, drill, and safety skills. Conclusion: Using a Persian-version tool that is adjusted to the socio-cultural determinants and native language may result in more trustful information on earthquake preparedness. It is suggested that disaster managers and researchers apply this tool in their future household preparedness projects. Further research is needed to make effective policies and plans for transforming preparedness knowledge into behavior. PMID:26981326

  19. Reliability of variables on the North Carolina birth certificate: a comparison with directly queried values from a cohort study

    PubMed Central

    Vinikoor, Lisa C.; Messer, Lynne C.; Laraia, Barbara A.; Kaufman, Jay S.

    2012-01-01

    Summary Birth records are an important source of data for examining population-level birth outcomes, but questions about the reliability of these vital records exist. We sought to assess the reliability of birth certificate data by comparing them with data from a large prospective cohort. Pregnancy, Infection, and Nutrition cohort study participants were matched with their birth certificates to assess agreement for maternal demographics, health behaviours, previous pregnancies and major pregnancy events. Agreement among categorical variables was assessed using percentage agreement and kappa statistics; for continuous variables, Spearman’s correlations and concordance correlation coefficients were used. The majority of variables had high agreement between the two data sources, especially for maternal demographic and birth outcome variables. Variables measuring anaemia, gestational diabetes and alcohol consumption showed the lowest correlations. Number of cigarettes smoked and number of previous pregnancies differed by education categories. For most variables, birth records appear to be a good source of reliable information. With the exception of a few variables that differed by education, most variables did not differ by stratum of race or education. Our research further supports the use of birth certificates as a reliable source of population-level data. PMID:20078836

  20. Reliability of variables on the North Carolina birth certificate: a comparison with directly queried values from a cohort study.

    PubMed

    Vinikoor, Lisa C; Messer, Lynne C; Laraia, Barbara A; Kaufman, Jay S

    2010-01-01

    Birth records are an important source of data for examining population-level birth outcomes, but questions about the reliability of these vital records exist. We sought to assess the reliability of birth certificate data by comparing them with data from a large prospective cohort. Pregnancy, Infection, and Nutrition cohort study participants were matched with their birth certificates to assess agreement for maternal demographics, health behaviours, previous pregnancies and major pregnancy events. Agreement among categorical variables was assessed using percentage agreement and kappa statistics; for continuous variables, Spearman's correlations and concordance correlation coefficients were used. The majority of variables had high agreement between the two data sources, especially for maternal demographic and birth outcome variables. Variables measuring anaemia, gestational diabetes and alcohol consumption showed the lowest correlations. Number of cigarettes smoked and number of previous pregnancies differed by education categories. For most variables, birth records appear to be a good source of reliable information. With the exception of a few variables that differed by education, most variables did not differ by stratum of race or education. Our research further supports the use of birth certificates as a reliable source of population-level data.

  1. Network Challenges for Cyber Physical Systems with Tiny Wireless Devices: A Case Study on Reliable Pipeline Condition Monitoring

    PubMed Central

    Ali, Salman; Qaisar, Saad Bin; Saeed, Husnain; Farhan Khan, Muhammad; Naeem, Muhammad; Anpalagan, Alagan

    2015-01-01

    The synergy of computational and physical network components leading to the Internet of Things, Data and Services has been made feasible by the use of Cyber Physical Systems (CPSs). CPS engineering promises to impact system condition monitoring for a diverse range of fields from healthcare, manufacturing, and transportation to aerospace and warfare. CPS for environment monitoring applications completely transforms human-to-human, human-to-machine and machine-to-machine interactions with the use of Internet Cloud. A recent trend is to gain assistance from mergers between virtual networking and physical actuation to reliably perform all conventional and complex sensing and communication tasks. Oil and gas pipeline monitoring provides a novel example of the benefits of CPS, providing a reliable remote monitoring platform to leverage environment, strategic and economic benefits. In this paper, we evaluate the applications and technical requirements for seamlessly integrating CPS with sensor network plane from a reliability perspective and review the strategies for communicating information between remote monitoring sites and the widely deployed sensor nodes. Related challenges and issues in network architecture design and relevant protocols are also provided with classification. This is supported by a case study on implementing reliable monitoring of oil and gas pipeline installations. Network parameters like node-discovery, node-mobility, data security, link connectivity, data aggregation, information knowledge discovery and quality of service provisioning have been reviewed. PMID:25815444

  2. Network challenges for cyber physical systems with tiny wireless devices: a case study on reliable pipeline condition monitoring.

    PubMed

    Ali, Salman; Qaisar, Saad Bin; Saeed, Husnain; Khan, Muhammad Farhan; Naeem, Muhammad; Anpalagan, Alagan

    2015-03-25

    The synergy of computational and physical network components leading to the Internet of Things, Data and Services has been made feasible by the use of Cyber Physical Systems (CPSs). CPS engineering promises to impact system condition monitoring for a diverse range of fields from healthcare, manufacturing, and transportation to aerospace and warfare. CPS for environment monitoring applications completely transforms human-to-human, human-to-machine and machine-to-machine interactions with the use of Internet Cloud. A recent trend is to gain assistance from mergers between virtual networking and physical actuation to reliably perform all conventional and complex sensing and communication tasks. Oil and gas pipeline monitoring provides a novel example of the benefits of CPS, providing a reliable remote monitoring platform to leverage environment, strategic and economic benefits. In this paper, we evaluate the applications and technical requirements for seamlessly integrating CPS with sensor network plane from a reliability perspective and review the strategies for communicating information between remote monitoring sites and the widely deployed sensor nodes. Related challenges and issues in network architecture design and relevant protocols are also provided with classification. This is supported by a case study on implementing reliable monitoring of oil and gas pipeline installations. Network parameters like node-discovery, node-mobility, data security, link connectivity, data aggregation, information knowledge discovery and quality of service provisioning have been reviewed.

  3. Food and beverage environment analysis and monitoring system: a reliability study in the school food and beverage environment.

    PubMed

    Bullock, Sally Lawrence; Craypo, Lisa; Clark, Sarah E; Barry, Jason; Samuels, Sarah E

    2010-07-01

    States and school districts around the country are developing policies that set nutrition standards for competitive foods and beverages sold outside of the US Department of Agriculture's reimbursable school lunch program. However, few tools exist for monitoring the implementation of these new policies. The objective of this research was to develop a computerized assessment tool, the Food and Beverage Environment Analysis and Monitoring System (FoodBEAMS), to collect data on the competitive school food environment and to test the inter-rater reliability of the tool among research and nonresearch professionals. FoodBEAMS was used to collect data in spring 2007 on the competitive foods and beverages sold in 21 California high schools. Adherence of the foods and beverages to California's competitive food and beverage nutrition policies for schools (Senate Bills 12 and 965) was determined using the data collected by both research and nonresearch professionals. The inter-rater reliability between the data collectors was assessed using the intraclass correlation coefficient. Researcher vs researcher and researcher vs nonresearcher inter-rater reliability was high for both foods and beverages, with intraclass correlation coefficients ranging from .972 to .987. Results of this study provide evidence that FoodBEAMS is a promising tool for assessing and monitoring adherence to nutrition standards for competitive foods sold on school campuses and can be used reliably by both research and nonresearch professionals.

  4. Reliability and validity of the Adolescent Stress Questionnaire in a sample of European adolescents - the HELENA study

    PubMed Central

    2011-01-01

    Background Since stress is hypothesized to play a role in the etiology of obesity during adolescence, research on associations between adolescent stress and obesity-related parameters and behaviours is essential. Due to lack of a well-established recent stress checklist for use in European adolescents, the study investigated the reliability and validity of the Adolescent Stress Questionnaire (ASQ) for assessing perceived stress in European adolescents. Methods The ASQ was translated into the languages of the participating cities (Ghent, Stockholm, Vienna, Zaragoza, Pecs and Athens) and was implemented within the HELENA cross-sectional study. A total of 1140 European adolescents provided a valid ASQ, comprising 10 component scales, used for internal reliability (Cronbach α) and construct validity (confirmatory factor analysis or CFA). Contributions of socio-demographic (gender, age, pubertal stage, socio-economic status) characteristics to the ASQ score variances were investigated. Two-hundred adolescents also provided valid saliva samples for cortisol analysis to compare with the ASQ scores (criterion validity). Test-retest reliability was investigated using two ASQ assessments from 37 adolescents. Results Cronbach α-values of the ASQ scales (0.57 to 0.88) demonstrated a moderate internal reliability of the ASQ, and intraclass correlation coefficients (0.45 to 0.84) established an insufficient test-retest reliability of the ASQ. The adolescents' gender (girls had higher stress scores than boys) and pubertal stage (those in a post-pubertal development had higher stress scores than others) significantly contributed to the variance in ASQ scores, while their age and socio-economic status did not. CFA results showed that the original scale construct fitted moderately with the data in our European adolescent population. Only in boys, four out of 10 ASQ scale scores were a significant positive predictor for baseline wake-up salivary cortisol, suggesting a rather poor

  5. Reliability analysis using an exponential power model with bathtub-shaped failure rate function: a Bayes study.

    PubMed

    Shehla, Romana; Khan, Athar Ali

    2016-01-01

    Models with bathtub-shaped hazard function have been widely accepted in the field of reliability and medicine and are particularly useful in reliability related decision making and cost analysis. In this paper, the exponential power model capable of assuming increasing as well as bathtub-shape, is studied. This article makes a Bayesian study of the same model and simultaneously shows how posterior simulations based on Markov chain Monte Carlo algorithms can be straightforward and routine in R. The study is carried out for complete as well as censored data, under the assumption of weakly-informative priors for the parameters. In addition to this, inference interest focuses on the posterior distribution of non-linear functions of the parameters. Also, the model has been extended to include continuous explanatory variables and R-codes are well illustrated. Two real data sets are considered for illustrative purposes.

  6. Preventative Maintenance and Reliability Study for the Central Heating and Power Plant at Fort Wainwright, Alaska

    DTIC Science & Technology

    2007-09-01

    RCM system to provide the high reliability that is required of the CHPP. A budget estimate for the RCM program recommended herein will range in...includes one clinker grinder in each of the four dog- houses of the bottom ash hopper for each boiler. The bottom ash is con- veyed by vacuum in an 8-in...bottom ash collection. 2. The system was converted from intermittent type to continuous proc- ess and automated. 3. New 30 t/h clinker grinders were

  7. Preventive Maintenance and Reliability Study for the Central Heating and Power Plant at Fort Wainwright, Alaska

    DTIC Science & Technology

    2007-09-01

    RCM system to provide the high reliability that is required of the CHPP. A budget estimate for the RCM program recommended herein will range in...includes one clinker grinder in each of the four dog- houses of the bottom ash hopper for each boiler. The bottom ash is con- veyed by vacuum in an 8-in...bottom ash collection. 2. The system was converted from intermittent type to continuous proc- ess and automated. 3. New 30 t/h clinker grinders were

  8. Chip-on-Board Technology 1996 Year-end Report (Design, Manufacturing, and Reliability Study)

    NASA Technical Reports Server (NTRS)

    Le, Binh Q.; Nhan, Elbert; Maurer, Richard H.; Lew, Ark L.; Lander, Juan R.

    1996-01-01

    The major impetus for flight qualifying Chip-On-Board (COB) packaging technology is the shift in emphasis for space missions to smaller, better, and cheaper spacecraft and satellites resulting from the NASA New Millenium initiative and similar requirements in DoD-sponsored programs. The most important benefit that can potentially be derived from miniaturizing spacecraft and satellites is the significant cost saving realizable if a smaller launch vehicle may be employed. Besides the program cost saving, there are several other advantages to building COB-based space hardware. First, once a well-controlled process is established, COB can be low cost compared to standard Multi-Chip Module (MCM) technology. This cost competitiveness is regarded as a result of the generally greater availability and lower cost of Known Good Die (KGD). Coupled with the elimination of the first level of packaging (chip package), compact, high-density circuit boards can be realized with Printed Wiring Boards (PWB) that can now be made with ever-decreasing feature size in line width and via hole. Since the COB packaging technique in this study is based mainly on populating bare dice on a suitable multi-layer laminate substrate which is not hermetically sealed, die coating for protection from the environment is required. In recent years, significant improvements have been made in die coating materials which further enhance the appeal of COB. Hysol epoxies, silicone, parylene and silicon nitride are desirable because of their compatible Thermal Coefficient of Expansion (TCE) and good moisture resistant capability. These die coating materials have all been used in the space and other industries with varying degrees of success. COB technology, specifically siliconnitride coated hardware, has been flown by Lockheed on the Polar satellite. In addition, DARPA has invested a substantial amount of resources on MCM and COB-related activities recently. With COB on the verge of becoming a dominant player

  9. Basis for the power supply reliability study of the 1 MW neutron source

    SciTech Connect

    McGhee, D.G.; Fathizadeh, M.

    1993-07-01

    The Intense Pulsed Neutron Source (IPNS) upgrade to 1 MW requires new power supply designs. This paper describes the tools and the methodology needed to assess the reliability of the power supplies. Both the design and operation of the power supplies in the synchrotron will be taken into account. To develop a reliability budget, the experiments to be conducted with this accelerator are reviewed, and data is collected on the number and duration of interruptions possible before an experiment is required to start over. Once the budget is established, several accelerators of this type will be examined. The budget is allocated to the different accelerator systems based on their operating experience. The accelerator data is usually in terms of machine availability and system down time. It takes into account mean time to failure (MTTF), time to diagnose, time to repair or replace the failed components, and time to get the machine back online. These estimated times are used as baselines for the design. Even though we are in the early stage of design, available data can be analyzed to estimate the MTTF for the power supplies.

  10. Reliability of accelerometer-determined physical activity and sedentary behavior in school-aged children: a 12-country study

    PubMed Central

    Barreira, T V; Schuna, J M; Tudor-Locke, C; Chaput, J-P; Church, T S; Fogelholm, M; Hu, G; Kuriyan, R; Kurpad, A; Lambert, E V; Maher, C; Maia, J; Matsudo, V; Olds, T; Onywera, V; Sarmiento, O L; Standage, M; Tremblay, M S; Zhao, P; Katzmarzyk, P T

    2015-01-01

    Objectives: Focused on the accelerometer-determined physical activity and sedentary time metrics in 9–11-year-old children, we sought to determine the following: (i) number of days that are necessary to achieve reliable estimates (G⩾0.8); (ii) proportion of variance attributed to different facets (participants and days) of reliability estimates; and (iii) actual reliability of data as collected in The International Study of Childhood Obesity, Lifestyle and Environment (ISCOLE). Methods: The analytical sample consisted of 6025 children (55% girls) from sites in 12 countries. Physical activity and sedentary time metrics measures were assessed for up to 7 consecutive days for 24 h per day with a waist-worn ActiGraph GT3X+. Generalizability theory using R software was used to investigate the objectives i and ii. Intra-class correlation coefficients (ICC) were computed using SAS PROC GLM to inform objective iii. Results: The estimated minimum number of days required to achieve a reliability estimate of G⩾0.8 ranged from 5 to 9 for boys and 3 to 11 for girls for light physical activity (LPA); 5 to 9 and 3 to 10, for moderate-to-vigorous physical activity (MVPA); 5 to 10 and 4 to 10 for total activity counts; and 7 to 11 and 6 to 11 for sedentary time, respectively. For all variables investigated, the ‘participant' facet accounted for 30–50% of the variability, whereas the ‘days' facet accounted for ⩽5%, and the interaction (P × D) accounted for 50–70% of the variability. The actual reliability for boys in ISCOLE ranged from ICCs of 0.78 to 0.86, 0.73 to 0.85 and 0.72 to 0.86 for LPA, MVPA and total activity counts, respectively, and 0.67 to 0.79 for sedentary time. The corresponding values for girls were 0.80–0.88, 0.70–0.89, 0.74–0.86 and 0.64–0.80. Conclusions: It was rare that only 4 days from all participants would be enough to achieve desirable reliability estimates. However, asking participants to wear the device for 7 days and requiring

  11. A new study of describing the reliability of GNSS Network RTK positioning with the use of quality indicators

    NASA Astrophysics Data System (ADS)

    Prochniewicz, D.; Szpunar, R.; Walo, J.

    2017-01-01

    The method of precise GNSS positioning using corrections from a network of reference stations, the so-called Network RTK, is currently the most accurate real time kinematic positioning method. The reliability of this method is largely dependent on the accuracy of determination of network ionospheric and geometric corrections (taking into account the tropospheric refraction and orbit errors). There are many indexes describing the reliability of Network RTK positioning in the aspect of the accuracy of modelling these errors. The so-called solution quality indicators are used for this purpose. They are parameters determined in the central network pre-processing which provide quantitative information regarding the predicted reliability of the positioning in an area encompassed by a network of reference stations. Unfortunately, their interpretation is hindered due to the lack of connection with basic parameters describing precise positioning quality, i.e. the correctness of the carrier phase ambiguity resolution and the accuracy of the rover position. This study presents a new approach to the design of quality indicators for the Network RTK method, based on a quantitative description of two parameters—solution accuracy and availability. The presented method is based on the existing parameters describing the probability of the correct fixing of ambiguities and the estimation of the fixed baseline solution accuracy. However, a stochastic model of observation, taking into account the accuracy of network corrections is used for these calculations. The proposed method enables a full account of all parameters affecting the reliability of positioning, which is not possible with the currently applied methods. Numerical tests of the new indicators carried out for a part of the regional reference stations network confirmed the effectiveness of this approach. The proposed indicators provide much more clear identification of the time periods for which the reliability of the

  12. Sitting bodily configuration: a study investigating the intra-tester reliability of positioning subjects into a predetermined sitting posture.

    PubMed

    Korakakis, Vasileios; Sideris, Vasilis; Giakas, Giannis

    2014-06-01

    Sitting posture predominates in lifestyle and workplace, but quantitative postural designation is limited due to divergence of methodology used in the studies. To date, no study has investigated the upper body's habitual or a predetermined sitting posture in healthy individuals assessing together pelvis, spine and head. The objectives were (i) assessment of intra-rater reliability of positioning subjects to a lordotic sitting posture and (ii) comparison of habitual sitting posture (HSP) with the lordotic posture. Another objective was to synthesize and propose an improved 3D model for pelvis, trunk and head to assess quantitatively the postural sagittal configuration. A single session test-retest design was employed. After power calculations 25 subjects were recruited. A repeated measure ANOVA revealed significant differences between HSP and the predetermined posture used in the study. Intra-rater reliability was analysed used the intra-class correlation coefficient (ICC) and also standard error of measurement (SEM) and smallest real difference (SRD) were calculated. The ICC values for all angles ranged from 0.85 to 0.98 indicating almost perfect agreement. The SEMs for all angles ranged in degrees from 0.65 to 1.50 and the SRDs from 1.80 to 4.16. This study provides the most specific sagittal measurement of surface spinal curves, head and pelvis position, in reference to a lordotic seated posture. The clinical significance of this study is reinforced by the fact that postural assessment is conducted by body surface evaluation. The results regarding reliability and SEMs established that healthy individuals can be reliably positioned in an upright lordotic sitting posture.

  13. Measurement of craniovertebral angle by the Modified Head Posture Spinal Curvature Instrument: A reliability and validity study.

    PubMed

    Subbarayalu, Arun Vijay

    2016-01-01

    The Modified Head Posture Spinal Curvature Instrument (MHPSCI) is an extension of the Head Posture Spinal Curvature Instrument. Two specific modifications were made in the original design by adding a third arm projecting horizontally from the protractor to objectively fix the pivot exactly over the C7 vertebra and the addition of a spirit-level to properly align the instrument. In order to demonstrate reliability and validity, this study was conducted using patients with postural neck pain (N = 65) and healthy subjects (N = 20). All the subjects were working at a selected Information Technology Industry in India and had been recruited using a criterion-based sampling approach. The craniovertebral (CV) angle of each subject was evaluated by two raters consecutively. The measurements were taken by using both MHPSCI and the standard photographic method in a standardized sitting posture for the purpose of establishing criterion-validity of the instrument. The results of this study indicate a good inter-rater reliability (ICC = 0.76; CI = 0.65-0.84) as well as intra-rater reliability (ICC = 0.87; CI = 0.82-0.91) between three successive CV angle measurements (with 2 minutes interval between each measurement) through MHPSCI. While keeping the digital photographic measurement as a standard, this study established that the MHPSCI is a valid tool for measuring the CV angle as shown by non-significant difference (p > 0.01) and high correlation between the two methods (r = 0.79-0.84). This study demonstrates that the MHPSCI is a reliable and valid instrument for measuring CV angle in subjects with or without postural neck pain.

  14. Reliability of meat, fish, dairy, and egg intake over a 33-year interval in Adventist Health Study 2.

    PubMed

    Singh, Pramil N; Batech, Michael; Faed, Pegah; Jaceldo-Siegl, Karen; Martins, Marcia; Fraser, Gary E

    2014-01-01

    We studied Adventist Health Study 2 (AHS-2) cohort members to determine the reliability of long-term recall of adult dietary intake that occurred 33 years ago. Establishing the reliability of these measures supports studies of how dietary exposure across the life course affects risk of cancer and other noncommunicable disease outcomes. Among 1816 AHS-2 cohort members, we conducted a statistical comparison of long-term recall of meat, fish, dairy, and eggs at AHS-2 baseline with their report of current diet 33 years before AHS-2 baseline at an age of 30-60 years. Major findings are as follows: 1) a high correlation for frequency of red meat (R = 0.71), poultry (R = 0.67), and fish (R = 0.60); lower correlations for dairy (R = 0.19) and eggs (R = 0.28); 2) good concordance for dichotomous measures of red meat [sensitivity: 0.70; specificity: 0.92; positive predictive value (PPV): 0.91], poultry (sensitivity: 0.76; specificity: 0.87; PPV: 0.83), fish (sensitivity: 0.61; specificity: 0.93; PPV: 0.89), dairy (sensitivity: 0.95; specificity: 0.57; PPV: 0.99), and eggs (sensitivity: 0.95; specificity: 0.41; PPV: 0.96); negative predictive value for dairy and eggs was poor. Among older AHS-2 cohort members, we found good reliability of recall of red meat, poultry, and fish intake that occurred 33 years earlier.

  15. Effect of system workload on operating system reliability - A study on IBM 3081

    NASA Technical Reports Server (NTRS)

    Iyer, R. K.; Rossetti, D. J.

    1985-01-01

    This paper presents an analysis of operating system failures on an IBM 3081 running VM/SP. Three broad categories of software failures are found: error handling, program control or logic, and hardware related; it is found that more than 25 percent of software failures occur in the hardware/software interface. Measurements show that results on software reliability cannot be considered representative unless the system workload is taken into account. The overall CPU execution rate, although measured to be close to 100 percent most of the time, is not found to correlate strongly with the occurrence of failures. Possible reasons for the observed workload failure dependency, based on detailed investigations of the failure data, are discussed.

  16. Reliability-Based Design of a Safety-Critical Automation System: A Case Study

    NASA Technical Reports Server (NTRS)

    Carroll, Carol W.; Dunn, W.; Doty, L.; Frank, M. V.; Hulet, M.; Alvarez, Teresa (Technical Monitor)

    1994-01-01

    In 1986, NASA funded a project to modernize the NASA Ames Research Center Unitary Plan Wind Tunnels, including the replacement of obsolescent controls with a modern, automated distributed control system (DCS). The project effort on this system included an independent safety analysis (ISA) of the automation system. The purpose of the ISA was to evaluate the completeness of the hazard analyses which had already been performed on the Modernization Project. The ISA approach followed a tailoring of the risk assessment approach widely used on existing nuclear power plants. The tailoring of the nuclear industry oriented risk assessment approach to the automation system and its role in reliability-based design of the automation system is the subject of this paper.

  17. An analytical study of relay neuron's reliability: dependence on input and model parameters.

    PubMed

    Agarwal, Rahul; Sarma, Sridevi V

    2011-01-01

    Relay neurons are widely found in our nervous system, including the Thalamus, spinal cord and lateral geniculate body. They receive a modulating input (background activity) and a reference input. The modulating input modulates relay of the reference input. This modulation is critical for correct functioning of relay neurons, but is poorly understood. In this paper, we use a biophysical-based model and systems theoretic tools to calculate how well a single relay neuron relays a reference input signal as a function of the neuron's electro physiological properties (i.e. model parameters), the modulating signal, and the reference signal parameters. Our analysis is more rigorous than previous related works and is generalizable to all relay cells in the body. Our analytical expression matches relay performance obtained in simulation and suggest that increasing the frequency of a sinusoidal modulating input or decreasing its DC offset increases the relay cell reliability.

  18. Reliability of fMRI for Studies of Language in Post-Stroke Aphasia Subjects

    PubMed Central

    Eaton, Kenneth P.; Szaflarski, Jerzy P.; Altaye, Mekibib; Ball, Angel L.; Kissela, Brett M.; Banks, Christi; Holland, Scott K.

    2008-01-01

    Quantifying change in brain activation patterns associated with post-stroke recovery and reorganization of language function over time requires accurate understanding of inter-scan and inter-subject variability. Here we report inter-scan variability measures for fMRI activation patterns associated with verb generation (VG) and semantic decision/tone decision (SDTD) tasks in 4 healthy controls and 4 aphasic left middle cerebral artery (LMCA) stroke subjects. A series of 10 fMRI scans was completed on a 4T Varian scanner for each task for each subject, except for one stroke subject who completed 5 and 6 scans for SDTD and VG, thus yielding 35 and 36 total stroke subject scans for SDTD and VG, respectively. Group composite and intraclass correlation coefficient (ICC) maps were computed across all subjects and trials for each task. The patterns of reliable activation for the VG and SDTD tasks correspond well to those regions typically activated by these tasks in healthy and aphasic subjects. ICCs for activation were consistently high (R0.05 ≈ 0.8) for individual tasks among both control and aphasic subjects. These voxel-wise measures of reliability highlight regions of low inter-scan variability within language circuitry for control and post-recovery stroke subjects. ICCs computed from the combination of the SDTD/VG data were markedly reduced for both control and aphasic subjects as compared with the ICCs for the individual tasks. These quantitative measures of inter-scan variability support the proposed use of these fMRI paradigms for longitudinal mapping of neural reorganization of language processing following left hemispheric insult. PMID:18411061

  19. Software Reliability 2002

    NASA Technical Reports Server (NTRS)

    Wallace, Dolores R.

    2003-01-01

    In FY01 we learned that hardware reliability models need substantial changes to account for differences in software, thus making software reliability measurements more effective, accurate, and easier to apply. These reliability models are generally based on familiar distributions or parametric methods. An obvious question is 'What new statistical and probability models can be developed using non-parametric and distribution-free methods instead of the traditional parametric method?" Two approaches to software reliability engineering appear somewhat promising. The first study, begin in FY01, is based in hardware reliability, a very well established science that has many aspects that can be applied to software. This research effort has investigated mathematical aspects of hardware reliability and has identified those applicable to software. Currently the research effort is applying and testing these approaches to software reliability measurement, These parametric models require much project data that may be difficult to apply and interpret. Projects at GSFC are often complex in both technology and schedules. Assessing and estimating reliability of the final system is extremely difficult when various subsystems are tested and completed long before others. Parametric and distribution free techniques may offer a new and accurate way of modeling failure time and other project data to provide earlier and more accurate estimates of system reliability.

  20. Regional electroencephalogram (EEG) alpha power and asymmetry in older adults: a study of short-term test-retest reliability.

    PubMed

    Mathewson, Karen J; Hashemi, Ali; Sheng, Bruce; Sekuler, Allison B; Bennett, Patrick J; Schmidt, Louis A

    2015-01-01

    Although regional alpha power and asymmetry measures have been widely used as indices of individual differences in emotional processing and affective style in younger populations, there have been relatively few studies that have examined these measures in older adults. Here, we examined the short-term test-retest reliability of resting regional alpha power (7.5-12.5 Hz) and asymmetry in a sample of 38 active, community-dwelling older adults (M age = 71.2, SD = 6.5 years). Resting electroencephalogram recordings were made before and after a perceptual computer task. Pearson and intra-class correlations indicated acceptable test-retest reliability for alpha power and asymmetry measures in all regions. Interestingly, alpha asymmetry appeared to be less affected by the task than was alpha power. Findings suggest that alpha asymmetry may reflect more enduring, "trait-like" characteristics, while alpha power may reflect more "state-like" processes in older adults.

  1. Remote Assessment of Cognitive Function in Juvenile Neuronal Ceroid Lipofuscinosis (Batten disease) – a Pilot Study of Feasibility and Reliability

    PubMed Central

    Ragbeer, Shayne N.; Augustine, Erika F.; Mink, Jonathan W.; Thatcher, Alyssa R.; Vierhile, Amy E.; Adams, Heather R.

    2015-01-01

    Remote technology provides an opportunity to extend the reach of clinical care and research for pediatric rare disease. This pilot study evaluated the feasibility and reliability of neuropsychological evaluation, using remote audiovisual technology, in the assessment of children with juvenile Batten disease. Three children with Batten disease and one healthy sibling completed a standardized cognitive assessment. Results indicated high agreement between an in-person and a remote evaluator, when comparing the subjects’ cognitive test scores. This initial test of remote cognitive assessment suggests it is feasible and reliable in children with pediatric neurodegenerative disease, for whom disease burden may limit travel and access to expert care and/or clinical trials. PMID:26336202

  2. Reliability and Validity Study of the Chamorro Assisted Gait Scale for People with Sprained Ankles, Walking with Forearm Crutches

    PubMed Central

    Ridao-Fernández, Carmen; Ojeda, Joaquín; Benítez-Lugo, Marisa; Sevillano, José Luis

    2016-01-01

    Objective The aim of this study was to design and validate a functional assessment scale for assisted gait with forearm crutches (Chamorro Assisted Gait Scale—CHAGS) and to assess its reliability in people with sprained ankles. Design Thirty subjects who suffered from sprained ankle (anterior talofibular ligament first and second degree) were included in the study. A modified Delphi technique was used to obtain the content validity. The selected items were: pelvic and scapular girdle dissociation(1), deviation of Center of Gravity(2), crutch inclination(3), steps rhythm(4), symmetry of step length(5), cross support(6), simultaneous support of foot and crutch(7), forearm off(8), facing forward(9) and fluency(10). Two raters twice visualized the gait of the sample subjects which were recorded. The criterion-related validity was determined by correlation between CHAGS and Coding of eight criteria of qualitative gait analysis (Viel Coding). Internal consistency and inter and intra-rater reliability were also tested. Results CHAGS obtained a high and negative correlation with Viel Coding. We obtained a good internal consistency and the intra-class correlation coefficients oscillated between 0.97 and 0.99, while the minimal detectable changes were acceptable. Conclusion CHAGS scale is a valid and reliable tool for assessing assisted gait with crutches in people with sprained ankles to perform partial relief of lower limbs. PMID:27168236

  3. The modified gait abnormality rating scale in patients with a conversion disorder: a reliability and responsiveness study.

    PubMed

    Vandenberg, Justin M; George, Deanna R; O'Leary, Andrea J; Olson, Lindsay C; Strassburg, Kaitlyn R; Hollman, John H

    2015-01-01

    Individuals with conversion disorder have neurologic symptoms that are not identified by an underlying organic cause. Often the symptoms manifest as gait disturbances. The modified gait abnormality rating scale (GARS-M) may be useful for quantifying gait abnormalities in these individuals. The purpose of this study was to examine the reliability, responsiveness and concurrent validity of GARS-M scores in individuals with conversion disorder. Data from 27 individuals who completed a rehabilitation program were included in this study. Pre- and post-intervention videos were obtained and walking speed was measured. Five examiners independently evaluated gait performance according to the GARS-M criteria. Inter- and intrarater reliability of GARS-M scores were estimated with intraclass correlation coefficients (ICCs). Responsiveness was estimated with the minimum detectable change (MDC). Pre- to post-treatment changes in GARS-M scores were analyzed with a dependent t-test. The correlation between GARS-M scores and walking speed was analyzed to assess concurrent validity. GARS-M scores were quantified with good-to-excellent inter- (ICC = 0.878) and intrarater reliability (ICC = 0.989). The MDC was 2 points. Mean GARS-M scores decreased from 7 ± 5 at baseline to 1 ± 2 at discharge (t26 = 7.411, p < 0.001) and 85% of patients improved beyond the MDC. Furthermore, GARS-M scores and walking speed measurements were moderately correlated (r = -0.582, p = 0.004), indicating that the GARS-M has acceptable concurrent validity. Our findings provide evidence that the GARS-M scores are reliable, valid and responsive for quantifying gait abnormalities in patients with conversion disorder. GARS-M scores provide objective measures upon which treatment effects can be assessed.

  4. Lunar precursor missions for human exploration of Mars--III: studies of system reliability and maintenance.

    PubMed

    Mendell, W W; Heydorn, R P

    2004-01-01

    Discussions of future human expeditions into the solar system generally focus on whether the next explorers ought to go to the Moon or to Mars. The only mission scenario developed in any detail within NASA is an expedition to Mars with a 500-day stay at the surface. The technological capabilities and the operational experience base required for such a mission do not now exist nor has any self-consistent program plan been proposed to acquire them. In particular, the lack of an Abort-to-Earth capability implies that critical mission systems must perform reliably for 3 years or must be maintainable and repairable by the crew. As has been previously argued, a well-planned program of human exploration of the Moon would provide a context within which to develop the appropriate technologies because a lunar expedition incorporates many of the operational elements of a Mars expedition. Initial lunar expeditions can be carried out at scales consistent with the current experience base but can be expanded in any or all operational phases to produce an experience base necessary to successfully and safely conduct human exploration of Mars.

  5. Lunar precursor missions for human exploration of Mars--III: studies of system reliability and maintenance

    NASA Technical Reports Server (NTRS)

    Mendell, W. W.; Heydorn, R. P.

    2004-01-01

    Discussions of future human expeditions into the solar system generally focus on whether the next explorers ought to go to the Moon or to Mars. The only mission scenario developed in any detail within NASA is an expedition to Mars with a 500-day stay at the surface. The technological capabilities and the operational experience base required for such a mission do not now exist nor has any self-consistent program plan been proposed to acquire them. In particular, the lack of an Abort-to-Earth capability implies that critical mission systems must perform reliably for 3 years or must be maintainable and repairable by the crew. As has been previously argued, a well-planned program of human exploration of the Moon would provide a context within which to develop the appropriate technologies because a lunar expedition incorporates many of the operational elements of a Mars expedition. Initial lunar expeditions can be carried out at scales consistent with the current experience base but can be expanded in any or all operational phases to produce an experience base necessary to successfully and safely conduct human exploration of Mars. Published by Elsevier Ltd.

  6. Renewable Resource Integration Project - Scoping Study of Strategic Transmission, Operations, and Reliability Issues

    SciTech Connect

    Eto, Joseph; Budhraja, Vikram; Ballance, John; Dyer, Jim; Mobasheri, Fred; Eto, Joseph

    2008-07-01

    California is on a path to increase utilization of renewable resources. California will need to integrate approximately 30,000 megawatts (MW) of new renewable generation in the next 20 years. Renewable resources are typically located in remote locations, not near the load centers. Nearly two/thirds or 20,000 MW of new renewable resources needed are likely to be delivered to Los Angeles Basin transmission gateways. Integration of renewable resources requires interconnection to the power grid, expansion of the transmission system capability between the backbone power grid and transmission gateways, and increase in delivery capacity from transmission gateways to the local load centers. To scope the transmission, operations, and reliability issues for renewables integration, this research focused on the Los Angeles Basin Area transmission gateways where most of new renewables are likely. Necessary actions for successful renewables integration include: (1) Expand Los Angeles Basin Area transmission gateway and nomogram limits by 10,000 to 20,000 MW; (2) Upgrade local transmission network for deliverability to load centers; (3) Secure additional storage, demand management, automatic load control, dynamic pricing, and other resources that meet regulation and ramping needed in real time operations; (4) Enhance local voltage support; and (5) Expand deliverability from Los Angeles to San Diego and Northern California.

  7. Assessment of Osstell ISQ’s reliability for implant stability measurement: A cross-sectional clinical study

    PubMed Central

    Herrero-Climent, Mariano; Santos-García, Rocio; Jaramillo-Santos, Reyes; Romero-Ruiz, Manuel M.; Fernández-Palacin, Ana; Lázaro-Calvo, Pedro; Bullón, Pedro

    2013-01-01

    Resonance frequency analysis (RFA) allows assess implant stability by measuring implant oscillation frequency on the bone. RFA is an objective and non-invasive method for implant stability measurement, although scarce evidence has been provided so far on its reliability. Objectives: Assess the Osstell ISQ system’s reliability (i.e., its measurement reproducibility and repeatability) by means of the intraclass correlation coefficient (ICC) as statistical method. Study Desing: Implants stability registers were completed by means of Osstell ISQ on 85 implants on 23 patients. Six measurements were completed on each implant by means of two different SmartPegs (types I and II); that is, three consecutive measurements with each transducer. Results: Average ISQ was 72.40, 72.22 and 72.79, and 72.06, 72.59 and 72.82 in the first, second, and third measurements with SmartPegs I and II, respectively. Equal values or differences below three ISQ points were observed in 52.9% and 62.4% of the cases with SmartPegs I and II, respectively. The intraclass correlation coefficient was 0.97 for both SmartPegs, and repeatability and reproducibility also reached 0.97 for both SmartPegs. Conclusions: The RFA system Osstell ISQ presents almost perfect repeatability and reproducibility after intraclass correlation coefficient analysis. Osstell ISQ measurements are highly reliable regarding reproducibility. Therefore, one measurement proves enough. Key words:Dental implants, RFA, ISQ, implant stability, Osstell. PMID:24121909

  8. Comment on "Study on the reliable computation time of the numerical model using the sliding temporal correlation method"

    NASA Astrophysics Data System (ADS)

    Algaba, Antonio; Fernández-Sánchez, Fernando; Merino, Manuel; Rodríguez-Luis, Alejandro J.

    2016-11-01

    The paper, "Study on the reliable computation time of the numerical model using the sliding temporal correlation method," was published in Theoretical and Applied Climatology. In that work, the sliding temporal correlation analysis is employed to investigate the predictable time of two typical chaotic numerical models, namely the Lorenz system and the Chen chaotic system. However, it has been recently shown by us when using a linear scaling in time and state variables that generically, the Chen system is only a particular case of the Lorenz system, with time reversion if the parameter c is positive. Consequently, to study the Chen chaotic system is simply to consider the Lorenz system integrated backwards.

  9. Reliability of Malayalam version of Geriatric Oral Health Assessment Index among institutionalized elderly in Alleppey, Kerala (India): A pilot study

    PubMed Central

    Shekhawat, Kuldeep Singh; Chauhan, Arunima; Koshy, Anitha Ann; Rekha, P.; Kumar, Hemanth

    2016-01-01

    Background: Oral health has a profound effect on the daily activities of geriatric group. India being a multilingual country, it is essential that instruments used to evaluate the quality of life is in local languages. However, the validation and translational aspect are important before involving a larger cohort of geriatrics. Aim: To assess the reliability of Malayalam version of Geriatric Oral Health Assessment Index (GOHAI-m). Settings and Design: Institutionalized elderly in Alleppey, Kerala, cross-sectional study. Materials and Methods: The 12 items in GOHAI were translated into Malayalam using a back-translation technique. The comprehensibility of the Malayalam version was assessed by a pilot study. Fifty institutionalized elderly answered the questionnaire. Impact based on age and marital status was also assessed. Statistical Analysis: Independent sample t-test, Cronbach's alpha, test–retest reliability using intraclass correlation coefficient (ICC). Results: The mean GOHAI-m scores were higher for elderly participants with slightly more impact on quality of life such as for biting or chewing food, and lower mean GOHAI-m scores indicated a positive impact on quality of life such as their self-conscious of oral health. Cronbach's alpha of 0.677 was reached with 12 items. Item 12 had a negative item-total correlation, −0.016, the deletion of Item-12 increased the item correlation to 0.7. Test–retest reliability of 0.65 for ICC indicated moderate stability. Females had more impact than males (P < 0.05). Age and marital status had no impact on their quality of life. Conclusion: The primary analysis of GOHAI-m indicated moderate stability. The elimination of negative items depends on the objectives of the study and/or after conducting a larger study keeping in view various parameters of the study. PMID:27307659

  10. Reliability and validity of abbreviated surveys derived from the National Eye Institute Visual Function Questionnaire: The Study of Osteoporotic Fractures

    PubMed Central

    Gergana, Kodjebacheva; Coleman, Anne L.; Ensrud, Kristine E.; Cauley, Jane A.; Yu, Fei; Stone, Katie L.; Pedula, Kathryn L.; Hochberg, Marc C.; Mangione, Carol M.

    2010-01-01

    Purpose To test the reliability and validity of questionnaires shortened from the National Eye Institute 25-item Vision Function Questionnaire (NEI VFQ-9 and NEI VFQ-8). Design A cross-sectional multi-center cohort study. Methods Reliability was assessed by Cronbach alpha coefficients. Validity was evaluated by studying the association of vision-targeted quality-of-life composite scores with objective visual function measurements. Study population: A total of 5,482 women between the ages of 65 and 100 years participated in the Year-10 clinic visit in the Study of Osteoporotic Fractures (SOF). A total of 3,631 women with complete data were included in the visual acuity (VA) and visual field (VF) analysis of the NEI VFQ-9, which is defined for those who care to drive. and 5,311 in the analysis of the NEI VFQ-8. To assess differences in prevalent eye diseases, which were ascertained for a random sample of SOF participants, 853 and 1,237 women were included in the NEI VFQ-9 and the NEI VFQ-8 analyses, respectively. Results Cronbach alpha coefficient for the NEI VFQ-9 scale was 0.83 and that of the NEI VFQ-8 was 0.84. Using both questionnaires, women with VA worse than 20/40 had lower composite scores compared to those with VA 20/40 or better (p<0.001). Participants with mild, moderate, and severe binocular VF loss had lower composite scores compared to those with no binocular VF loss (p<0.001).Compared to women without chronic eye diseases in both eyes, women with at least one chronic eye disease in at least one eye had lower composite scores. Conclusions Both questionnaires showed high reliability across items and validity with respect to clinical markers of eye disease Future research should compare the properties of these shortened surveys to those of the NEI VFQ-25. PMID:20103058

  11. Reliability and validity of spinal coordination patterns during treadmill walking in persons with thoracic spine pain – a preliminary study

    PubMed Central

    2013-01-01

    Background Persons with low back pain fail to show the same transition as healthy individuals from in-phase to anti-phase rotation of the thorax and pelvis as walking speed increases. The purpose of this study was to determine if the relative phase of the thorax and pelvis during walking was a reliable (within day test-retest) and valid measure for persons with thoracic pain. Methods The time series motion of the spine over C7, T8 and sacrum were measured at five treadmill walking speeds (0.67, 0.89, 1.12, 1.34, 1.56 m/s) in 19 persons with thoracic spine pain and 19 healthy control subjects. After a 20 minute rest, all tests were repeated. The average relative phases of the transverse plane rotation between C7-T8, C7-sacrum and T8-sacrum during a one-minute walk were calculated. The standard error of measurement (SEM) and the intra-class correlation coefficient (ICC) were used to estimate test-retest reliability. Three-way repeated measures analyses of variance were performed to determine the influence of group, walking speed and session on the relative phases. Results The minimum transverse plane motion amplitudes, across all participants and speeds, for the C7-T8, C7-sacrum, and T8-sacrum were 2.9, 5.1 and 2.8 degrees, respectively. The C7-T8 relative phase changed little with speed. The C7-sacrum and T8-sacrum relative phases showed increases as subjects walked faster, but both groups had similar patterns of change. Only the C7-T8 relative phase at 0.67 and 0.89 m/s exhibited good reliability (ICC > 0.80, SEM 4.2-5.7, no significant time effects) for both groups. The C7-T8 and T8-sacrum relative phases demonstrated significant group by speed effects. Conclusions The C7-T8 relative phase showed reasonable reliability and some discrimination between groups, but changes in response to walking speed were small. The T8-sacrum relative phase showed some discriminative ability, but reliability was not adequate. PMID:24321275

  12. Experimental studies to improve the reliability and validity of regulatory judgments on health care in the Netherlands: a randomized controlled trial and before and after case study

    PubMed Central

    Tuijn, Saskia M; van den Bergh, Huub; Robben, Paul; Janssens, Frans

    2014-01-01

    Rationale, aims and objectives We examined the effect of two interventions on both the reliability and validity of regulatory judgments: adjusting the regulatory instrument and attending a consensus meeting. Method We adjusted the regulatory instrument. With a randomized controlled trial (RCT) we examined the effect of the adjustments we made to the instrument. In the consensus meeting inspectors discussed cases and had to reach consensus about the order of the cases. We used a before and after case study to assess the effect of the consensus meeting. We compared the judgments assigned in the RCT with the unadjusted instrument with the judgments assigned with the unadjusted instrument after the consensus meeting. Moreover we explored the effect of increasing the number of inspectors per regulatory visit based on the estimates of the two interventions. Results The consensus meeting improved the agreement between inspectors; the variance between inspectors was smallest (0.03) and the reliability coefficient was highest (0.59). Validity is assessed by examining the relation between the assigned judgments and the corporate standard and expressed by a correlation coefficient. This coefficient was highest after the consensus meeting (0.48). Adjustment of the instrument did not increase reliability and validity coefficients. Conclusions Participating in a consensus meeting improved reliability and validity. Increasing the number of inspectors resulted in both higher reliability and validity values. Organizing consensus meetings and increasing the number of inspectors per regulatory visit seem to be valuable interventions for improving regulatory judgments. PMID:24819044

  13. Reliability and Validity of Web-Based Portfolio Peer Assessment: A Case Study for a Senior High School's Students Taking Computer Course

    ERIC Educational Resources Information Center

    Chang, Chi-Cheng; Tseng, Kuo-Hung; Chou, Pao-Nan; Chen, Yi-Hui

    2011-01-01

    This study examined the reliability and validity of Web-based portfolio peer assessment. Participants were 72 second-grade students from a senior high school taking a computer course. The results indicated that: 1) there was a lack of consistency across various student raters on a portfolio, or inter-rater reliability; 2) two-thirds of the raters…

  14. Network reliability

    NASA Technical Reports Server (NTRS)

    Johnson, Marjory J.

    1985-01-01

    Network control (or network management) functions are essential for efficient and reliable operation of a network. Some control functions are currently included as part of the Open System Interconnection model. For local area networks, it is widely recognized that there is a need for additional control functions, including fault isolation functions, monitoring functions, and configuration functions. These functions can be implemented in either a central or distributed manner. The Fiber Distributed Data Interface Medium Access Control and Station Management protocols provide an example of distributed implementation. Relative information is presented here in outline form.

  15. Adaptation of Hunter Cynism Scale to Turkish: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Kiraz, Zafer; Bakioglu, Fuad

    2016-01-01

    The aim of this study is to carry out the adaptation of Hunter Cynicism Scale to Turkish. For this purpose, this study consists of two stages. 311 university students participated in for the first stage and 313 university students participated in for the second stage of this study. In the first stage, translation, exploratory factor analysis,…

  16. An Attitude Scale for Smart Board Use in Education: Validity and Reliability Studies

    ERIC Educational Resources Information Center

    Sad, Suleyman Nihat

    2012-01-01

    The main purpose of this study was to develop an instrument to measure the attitudes of elementary students towards smart board (SB) use in education. A sequential exploratory mixed method was used. So the study started with a qualitative approach to establish the content and face validity of the scale, followed by a quantitative approach to test…

  17. Unethical Computer Using Behavior Scale: A Study of Reliability and Validity on Turkish University Students

    ERIC Educational Resources Information Center

    Namlu, Aysen Gurcan; Odabasi, Hatice Ferhan

    2007-01-01

    This study was carried out in a Turkish university with 216 undergraduate students of computer technology as respondents. The study aimed to develop a scale (UECUBS) to determine the unethical computer use behavior. A factor analysis of the related items revealed that the factors were can be divided under five headings; intellectual property,…

  18. Elementary School Student Burnout Scale for Grades 6-8: A Study of Validity and Reliability

    ERIC Educational Resources Information Center

    Aypay, Ayse

    2011-01-01

    The purpose of this study is to develop an "Elementary School Student Burnout Scale for Grades 6-8". The study group included 691 students out of 10 schools in Eskisehir. Both Exploratory Factor Analysis and Confirmatory Factor Analysis were conducted on the data (Burnout stem from school activities, burnout stem from family, feeling of…

  19. Validity and Reliability Studies on the Scale of the Reasons for Academic Procrastination

    ERIC Educational Resources Information Center

    Yesil, Rustu

    2012-01-01

    The objective of this study is to develop a scale in order to determine the reasons why students delay academic tasks and the levels that they are affected from these reasons. The study group was composed of a total of 447 students from the faculty of education. The KMO value of this scale composed of 43 items collected under six factors was…

  20. The Reading Essential Skill Screener--Preschool Version (RESS-P): Studies of Reliability and Validity

    ERIC Educational Resources Information Center

    Erford, Bradley T.

    2004-01-01

    Technical characteristics of the Reading Essential Skill Screener--Preschool Version (RESS-P) were studied using four independent samples of boys and girls aged 3-5 years. A decision efficiency study (N = 91) resulted in a total predictive value (TPV) of .85 when compared with the criterion of teacher report/judgment of emerging literacy at-risk…

  1. Adaptation of Distributed Leadership Scale into Turkish: The Validity and Reliability Study

    ERIC Educational Resources Information Center

    Ersozlu, Alpay; Ulusoy, Tarik

    2016-01-01

    The purpose of this study was to adapt "Distributed Leadership Scale" originally developed by Davis into Turkish Language. A total of 386 participants including teachers employed in high schools in Tokat participated in the study. Explanatory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were performed to test the…

  2. Reliable Identification of Cross-Linked Products in Protein Interaction Studies by 13C-Labeled p-Benzoylphenylalanine

    NASA Astrophysics Data System (ADS)

    Pettelkau, Jens; Ihling, Christian H.; Frohberg, Petra; van Werven, Lars; Jahn, Olaf; Sinz, Andrea

    2014-09-01

    We describe the use of the 13C-labeled artificial amino acid p-benzoyl-L-phenylalanine (Bpa) to improve the reliability of cross-linked product identification. Our strategy is exemplified for two protein-peptide complexes. These studies indicate that in many cases the identification of a cross-link without additional stable isotope labeling would result in an ambiguous assignment of cross-linked products. The use of a 13C-labeled photoreactive amino acid is considered to be preferred over the use of deuterated cross-linkers as retention time shifts in reversed phase chromatography can be ruled out. The observation of characteristic fragment ions additionally increases the reliability of cross-linked product assignment. Bpa possesses a broad reactivity towards different amino acids and the derived distance information allows mapping of spatially close amino acids and thus provides more solid structural information of proteins and protein complexes compared to the longer deuterated amine-reactive cross-linkers, which are commonly used for protein 3D-structure analysis and protein-protein interaction studies.

  3. A study on reliability and validity of the Turkish version of the Face Anxiety Scale on mechanically-ventilated patients.

    PubMed

    Iyigun, Emine; Pazar, Berrin; Tastan, Sevinc

    2016-12-01

    Mechanical ventilation treatment causes patient anxiety, such that for those people dependent on mechanical ventilation, it was suggested to self-evaluate anxiety levels using a scale. The aim of this study was to assess the reliability and validity of the Turkish version of the Face Anxiety Scale in order to evaluate general patient anxiety levels for those receiving mechanical ventilation in a cardiovascular surgery (CVS) intensive care unit (ICU). A survey was conducted between April and December 2015 with 99 patients in receipt of mechanical ventilation at the CVS-ICU of a military training hospital in Turkey. Patients' average age was 59.31±16.47 years (range 18-83 years), with 73.7% for males and 73.7% for those undergoing coronary artery bypass graft surgery. The average scores from the Face Anxiety Scale were 2.8±1.3. A statistically significant (positive) correlation was found between scores from the test and retest (r=0.87, p<0.001), which indicated that the scale was reliable. The relationship between the Face Anxiety Scale and Profile of the Mood States (POMS) of participants scored 0.89, corroborating the validity of the former (p<0.001). This study found that it was valuable for evaluating patient anxiety in those receiving mechanical ventilation.

  4. Ultrasound virtual endoscopy: Polyp detection and reliability of measurement in an in vitro study with pig intestine specimens

    PubMed Central

    Liu, Jin-Ya; Chen, Li-Da; Cai, Hua-Song; Liang, Jin-Yu; Xu, Ming; Huang, Yang; Li, Wei; Feng, Shi-Ting; Xie, Xiao-Yan; Lu, Ming-De; Wang, Wei

    2016-01-01

    AIM: To present our initial experience regarding the feasibility of ultrasound virtual endoscopy (USVE) and its measurement reliability for polyp detection in an in vitro study using pig intestine specimens. METHODS: Six porcine intestine specimens containing 30 synthetic polyps underwent USVE, computed tomography colonography (CTC) and optical colonoscopy (OC) for polyp detection. The polyp measurement defined as the maximum polyp diameter on two-dimensional (2D) multiplanar reformatted (MPR) planes was obtained by USVE, and the absolute measurement error was analyzed using the direct measurement as the reference standard. RESULTS: USVE detected 29 (96.7%) of 30 polyps, remaining a 7-mm one missed. There was one false-positive finding. Twenty-six (89.7%) of 29 reconstructed images were clearly depicted, while 29 (96.7%) of 30 polyps were displayed on CTC with one false-negative finding. In OC, all the polyps were detected. The intraclass correlation coefficient was 0.876 (95%CI: 0.745-0.940) for measurements obtained with USVE. The pooled absolute measurement errors ± the standard deviations of the depicted polyps with actual sizes ≤ 5 mm, 6-9 mm, and ≥ 10 mm were 1.9 ± 0.8 mm, 0.9 ± 1.2 mm, and 1.0 ± 1.4 mm, respectively. CONCLUSION: USVE is reliable for polyp detection and measurement in in vitro study. PMID:27022217

  5. Reliability study on high-power 638nm broad stripe LD with a window-mirror structure

    NASA Astrophysics Data System (ADS)

    Yagi, Tetsuya; Mitsuyama, Hiroshi; Nishida, Takehiro; Kadoiwa, Kaoru; Kuramoto, Kyosuke

    2014-03-01

    Laser based displays, such as 10 lm to 70K lm laser projectors and laser diode (LD) backlight liquid crystal display (LCD) TVs, have attracted much attention because of the large gamut, low power consumption, and so on. Laser light sources for the displays are operated mainly under CW, and requested to be highly reliable. In this work, we will present the latest reliability study on high-power 638 nm broad stripe (BS) LD with a window-mirror structure, which is formed by using Zn diffusion into a quantum well active layer. Although the LD showed no catastrophic optical mirror degradation (COMD) even above the output of 1.6 W initially, the LDs aged at output power around 1.0 to 1.5 W showed sudden degradation during 1,000 to 4,000 hours. The duration to the failure became shorter as the power increased. Electro luminescence (EL) imaging revealed that the root cause of the sudden degradation was COMD at the front facet even though the LD had a measure to COMD. The LDs aged at 0.42 W output showed no COMD up to 6500 hours with extremely stable operation. The result also revealed that the mean time to failure due to COMD was proportional to optical density to the power of -3.2. The LDs, which had 60% small power density compared to the former, showed stable one up to 4,000 hours without COMD at 1.25 W. It is clarified that maintaining a low optical output power density is essential to develop high-power and highly reliable red BS-LDs.

  6. Reliability of tonosafe disposable tonometer prisms: clinical implications from the Veterans Affairs Boston Healthcare System Quality Assurance Study

    PubMed Central

    Thomas, V; Daly, M K; Cakiner-Egilmez, T; Baker, E

    2011-01-01

    Purpose Given the Veterans Affairs Boston Healthcare System's recent introduction of single-use Tonosafe disposable tonometer prisms as an alternative to Goldmann applanation tonometers (GATs), this study had two aims: to conduct a large-scale quality assurance trial to assess the reliability of intraocular pressure (IOP) measurements of the Tonosafe disposable tonometer compared with GAT, particularly at extremes of pressure; to evaluate the suitability of Tonosafe disposable tonometer prisms as an acceptable substitute for GATs and for clinic-wide implementation in an academic tertiary referral setting. Methods Ophthalmology resident physicians measured the IOPs of patients in general and specialty eye clinics with the Tonosafe disposable tonometer and GAT. Tonosafe test–retest reliability data were also collected. A retrospective review of patient charts and data analysis were performed to determine the reliability of measurements. Results The IOPs of 652 eyes (326 patients) were measured with both GAT and Tonosafe, with a range of 3–34 mm Hg. Linear regression analysis showed R=0.93, slope=0.91, both of which supported the proposed hypothesis, and the y-intercept=−1.05 was significantly different from the hypothesized value. The Tonosafe test–retest repeatability (40 eyes of 40 patients), r=0.977, was very high, which was further supported by linear regression slope=0.993, y-intercept=0.118, and a Tonosafe repeatability coefficient of 2.06, similar to GAT repeatability. Conclusions The IOP measurements by Tonosafe disposable prisms correlated closely with Goldmann measurements, with similar repeated measurement variability to GAT. This suggests that the Tonosafe is an acceptable substitute for GAT to measure IOP in ophthalmology clinic settings. PMID:21455241

  7. A confirmatory study of the Combined Index of Severity of Fibromyalgia (ICAF*): factorial structure, reliability and sensitivity to change

    PubMed Central

    2011-01-01

    Background Fibromyalgia (FM) is a complex syndrome that affects many aspects of the patients life and it is very difficult to evaluate in clinical practice. A recent study has developed the Combined Index of Severity of Fibromyalgia (ICAF), an instrument that evaluates diverse aspects of FM and offers five indices: emotional, physical, active coping, passive coping and total. The objective of this study is to confirm the structure of the ICAF, check its test-retest reliability, assess its sensitivity to change, and compare the results obtained in a sample of patients with fibromyalgia with another sample of healthy controls. Methods A total of 232 patients took part in the study, 228 women and 4 men, with a mean age of 47.73 years of age (SD = 8.61) and a time of disease evolution since diagnosis of 4.28 years (SD = 4.03). The patients from the FM group completed the ICAF. Between one and two weeks later, they again attended the clinic and complete the 59 items on the ICAF (retest) and immediately afterwards they began treatment (according to daily clinical practice criteria). A sample of healthy subjects was also studied as a control group: 110 people were included (106 women and 4 men) with a mean age of 46.01 years of age (SD = 9.35). The study was conducted in Spain. Results The results obtained suggest that the four-factor model obtained in the previous study adequately fits the data obtained in this study. The test-retest reliability and internal consistency were all significant and show a high degree of correlation for all the factors as well as in overall score. With the exception of the passive coping factor, all the other scores, including the overall score, were sensitive to change after the therapeutic intervention. The ICAF scores of the patients with fibromyalgia compared with those of the control group were markedly different. Conclusions The findings suggest that the ICAF is a valid, reliable, sensitive to change instrument with the added advantage

  8. Study of SEM induced current and voltage contrast modes to assess semiconductor reliability

    NASA Technical Reports Server (NTRS)

    Beall, J. R.

    1976-01-01

    The purpose of the scanning electron microscopy study was to review the failure history of existing integrated circuit technologies to identify predominant failure mechanisms, and to evaluate the feasibility of their detection using SEM application techniques. The study investigated the effects of E-beam irradiation damage and contamination deposition rates; developed the necessary methods for applying the techniques to the detection of latent defects and weaknesses in integrated circuits; and made recommendations for applying the techniques.

  9. Reliability of lip prints in personal identification: An inter-racial pilot study

    PubMed Central

    Kumar, Laliytha Bijai; Jayaraman, Venkatesh; Mathew, Philips; Ramasamy, S.; Austin, Ravi David

    2016-01-01

    Context: Forensic science is a branch of science that deals with the application of science and technology in solving a crime and this requires a multidisciplinary team effort. The word “Forensic” is derived from the Latin word, “Forensis” which means the study of public. Dental professionals should develop interests in contributing to legal issues. Aims: To study the lip prints among people of different races. Settings and Design: Descriptive study. Subjects and Methods: The present study comprised of ninety subjects of which Group A comprised of Africans, Group B comprised of Dravidian, and Group C of Mongoloid race. Each group was then further divided into 15 males and 15 females for whom the lip prints were recorded and evaluated. Statistical Analysis Used: ANOVA test. Results: ANOVA statistical analysis was used to compare three races of African, Dravidian, and Mongoloid races. The observed data among male and female were found to be significant with a P = 0.000492. Conclusion: The present study showed a significant difference in lip pattern among the three races. Perhaps future studies with a larger sample size and comparison between many other races may be done for better personal identification. PMID:28123283

  10. Systematic Review Shows Only Few Reliable Studies of Physical Activity Intervention in Adolescents

    PubMed Central

    Soares, Nara Michelle Moura; Leão, Arley Santos; Santos, Josivan Rosa; Monteiro, Glauber Rocha; dos Santos, Jorge Rollemberg; Thomazzi, Sara Maria; Silva, Roberto Jerônimo dos Santos

    2014-01-01

    Introduction. Several studies have pointed to the high prevalence of low levels of physical activity in adolescents, suggesting the need for more effective interventions for this group. The aim of this study was to present evidence of intervention programs for efficacy of physical activity for adolescents. Methods. Surveys in PubMed, SportDiscus, LiLacs, and SciELO databases were conducted using keywords to identify population, intervention, and outcome, as well as DeCS and MeSH terms in English, Portuguese, and Spanish, whenever appropriate. The review included observational studies with minimal intervention of six months, minimum sample size of 100 adolescents, written in any language, and those who have reached STROBE score greater than 70%. Results. Only seven studies met all inclusion criteria. Of these, five were pre- and postintervention and two had n > 2000 participants. Interventions were of several types, durations, and strategies for physical activity implementation. Behavior change was assessed in 43% of studies and three reported success in some way. Conclusion. Due to heterogeneity in their contents and methodologies, as well as the lack of jobs that accompany adolescents after the intervention period, one cannot draw conclusions about the actual effects of the intervention programs of physical activity on the behavior of young people. PMID:25152903

  11. Development of a mathematical ability test: a validity and reliability study

    NASA Astrophysics Data System (ADS)

    Dündar, Sefa; Temel, Hasan; Gündüz, Nazan

    2016-10-01

    The identification of talented students accurately at an early age and the adaptation of the education provided to the students depending on their abilities are of great importance for the future of the countries. In this regard, this study aims to develop a mathematical ability test for the identification of the mathematical abilities of students and the determination of the relationships between the structure of abilities and these structures. Furthermore, this study adopts test development processes. A structure consisting of the factors of quantitative ability, causal ability, inductive/deductive reasoning ability, qualitative ability and spatial ability has been obtained following this study. The fit indices of the finalized version of the mathematical ability test of 24 items indicate the suitability of the test.

  12. A Study of the Readiness of Hospitals for Implementation of High Reliability Organizations Model in Tehran University of Medical Sciences.

    PubMed

    Mousavi, Seyed Mohammad Hadi; Dargahi, Hossein; Mohammadi, Sara

    2016-10-01

    Creating a safe of health care system requires the establishment of High Reliability Organizations (HROs), which reduces errors, and increases the level of safety in hospitals. This model focuses on improving reliability through higher process design, building a culture of accreditation, and leveraging human factors. The present study intends to determine the readiness of hospitals for the establishment of HROs model in Tehran University of Medical Sciences from the viewpoint of managers of these hospitals. This is a descriptive-analytical study carried out in 2013-2014. The research population consists of 105 senior and middle managers of 15 hospitals of Tehran University of Medical Sciences. The data collection tool was a 55-question researcher-made questionnaire, included six elements of HROs to assess the level of readiness for establishing HROS model from managers' point of view. The validity of the questionnaire was calculated through the content validity method using 10 experts in the area of hospitals' accreditation, and its reliability was calculated through test-retest method with a correlation coefficient of 0.90. The response rate was 90 percent. The Likert scale was used for the questions, and data analysis was conducted through SPSS version 21 Descriptive statistics was presented via tables and normal distributions of data and means. Analytical methods, including t-test, Mann-Whitney, Spearman, and Kruskal-Wallis, were used for presenting inferential statistics. The study showed that from the viewpoint of senior and middle managers of the hospitals considered in this study, these hospitals are indeed ready for acceptance and establishment of HROs model. A significant relationship was showed between HROs model and its elements with demographic details of managers like their age, work experience, management experience, and level of management. Although the studied hospitals, as viewed by their managers, are capable of attaining the goals of HROs, it

  13. Development of a Mathematical Ability Test: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Dündar, Sefa; Temel, Hasan; Gündüz, Nazan

    2016-01-01

    The identification of talented students accurately at an early age and the adaptation of the education provided to the students depending on their abilities are of great importance for the future of the countries. In this regard, this study aims to develop a mathematical ability test for the identification of the mathematical abilities of students…

  14. Adaptation of Economy Attitude Scale to Turkish Culture: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Alagoz, Bullent

    2015-01-01

    Economics affects us no matter what role we play in social life. Its foundation as a science was laid by the studies of Adam Smith, and since history it has become one of the disciplines accepted in university curriculums. Scarcity, opportunity costs and abandoning something in order to obtain another one are the core concepts of this discipline.…

  15. Turkish Version of the Principals' Sense of Efficacy Scale: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Isik, Ayse Negis; Derinbay, Deniz

    2015-01-01

    Problem Statement: Principals are known as important actors in effective schools. So it is important to know which variables influence principals' success. One of these predictors can be self-efficacy. However, there is very few research about principals' sense of efficacy. Purpose of the Study: The purpose of this research was to test the…

  16. A Study of the Validity and Reliability of Self-Assessment

    ERIC Educational Resources Information Center

    Mistar, Junaidi

    2011-01-01

    This study is to investigate whether self-assessment contains construct-irrelevant variances of gender and age, and whether self-assessment correlates with test scores. The data were collected from seventy-eight newly arrived international students at the English Language Center, Michigan State University, USA. Prior to class commencement, they…

  17. Rating Performance Assessments of Students with Disabilities: A Study of Reliability and Bias

    ERIC Educational Resources Information Center

    Mastergeorge, Ann M.; Martinez, Jose Felipe

    2010-01-01

    Inclusion of students with disabilities in district-wide and state assessments is mandated by federal regulations, and teachers sometimes play an important role in rating these students' work. In this study, trained teachers rated student proficiency in performance assessments in language arts and mathematics in third, fifth, and ninth grades. The…

  18. Adaptation of Social Interaction Practices for the Preschool Years into Turkish: Validity and Reliability Study

    ERIC Educational Resources Information Center

    Samur, Ayse Ozturk; Soydan, Sema

    2013-01-01

    The aim of this study is to adapt SIPPY (social interaction practices for the preschool years) scale into Turkish. The SIPPY is a tool designed to assess teachers' judgments of the acceptability and feasibility, as well as their current use of literature-supported strategies for promoting the development of young children's social competence in…

  19. Wideband Acoustic Immittance: Normative Study and Test-Retest Reliability of Tympanometric Measurements in Adults

    ERIC Educational Resources Information Center

    Sun, Xiao-Ming

    2016-01-01

    Purpose: The purpose of this study was to present normative data of tympanometric measurements of wideband acoustic immittance and to characterize wideband tympanograms. Method: Data were collected in 84 young adults with strictly defined normal hearing and middle ear status. Energy absorbance (EA) was measured using clicks for 1/12-octave…

  20. Using Mathematics in Teaching Science Self-Efficacy Scale--UMSSS: A Validity and Reliability Study

    ERIC Educational Resources Information Center

    Can, Bilge Taskin; Gunhan, Berna Canturk; Erdal, Sevinc Ongel

    2012-01-01

    In this study, an instrument, Using Mathematics in Science Self-efficacy Scale (UMSSS), was developed in order to determine preservice science teachers' self-efficacy toward the use of mathematics in their lessons. Data gathered from 250 preservice science teachers were used for Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis…

  1. The Brief Symptom Inventory: A Validity-Reliability Study of a Sample from Azerbaijan

    ERIC Educational Resources Information Center

    Kerimova, Melek; Osmanli, Nermin

    2016-01-01

    The aim of this research was to adapt "Brief Symptom Inventory" developed by Derogatis (1983) into Azerbaijani language. Data were collected from 309 college students to determine psychometric properties of inventory. Samples in the study have been selected separately. The package programs of SPSS 18.0 and Lisrel 8.80 were used for the…

  2. Multidisciplinary System Reliability Analysis

    NASA Technical Reports Server (NTRS)

    Mahadevan, Sankaran; Han, Song; Chamis, Christos C. (Technical Monitor)

    2001-01-01

    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code, developed under the leadership of NASA Glenn Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multidisciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  3. Adaptation of the ToxRTool to Assess the Reliability of Toxicology Studies Conducted with Genetically Modified Crops and Implications for Future Safety Testing.

    PubMed

    Koch, Michael S; DeSesso, John M; Williams, Amy Lavin; Michalek, Suzanne; Hammond, Bruce

    2016-01-01

    To determine the reliability of food safety studies carried out in rodents with genetically modified (GM) crops, a Food Safety Study Reliability Tool (FSSRTool) was adapted from the European Centre for the Validation of Alternative Methods' (ECVAM) ToxRTool. Reliability was defined as the inherent quality of the study with regard to use of standardized testing methodology, full documentation of experimental procedures and results, and the plausibility of the findings. Codex guidelines for GM crop safety evaluations indicate toxicology studies are not needed when comparability of the GM crop to its conventional counterpart has been demonstrated. This guidance notwithstanding, animal feeding studies have routinely been conducted with GM crops, but their conclusions on safety are not always consistent. To accurately evaluate potential risks from GM crops, risk assessors need clearly interpretable results from reliable studies. The development of the FSSRTool, which provides the user with a means of assessing the reliability of a toxicology study to inform risk assessment, is discussed. Its application to the body of literature on GM crop food safety studies demonstrates that reliable studies report no toxicologically relevant differences between rodents fed GM crops or their non-GM comparators.

  4. The reliability studies of nano-engineered SiGe HBTs using Pelletron accelerator

    SciTech Connect

    Prakash, A. P. Gnana Praveen, K. C.; Pushpa, N.; Cressler, John D.

    2015-05-15

    The effects of high energy ions on the electrical characteristics of silicon-germanium heterojunction bipolar transistors (SiGe HBTs) were studied in the total dose of ranging from 600 krad to 100 Mrad (Si). The two generations (50 GHz and 200 GHz) of SiGe HBTs were exposed to 50 MeV lithium, 75 MeV boron and 100 MeV oxygen ions. The electrical characteristics of SiGe HBTs were studied before and after irradiation. The SiGe HBTs were exposed to {sup 60}Co gamma radiation in the same total dose. The results are systematically compared in order to understand the interaction of ions and ionizing radiation with SiGe HBTs.

  5. Methods for obtaining reliable and reproducible results in studies of Candida biofilms formed in vitro.

    PubMed

    Costa, Anna C B P; Pereira, Cristiane A; Freire, Fernanda; Junqueira, Juliana C; Jorge, Antonio O C

    2013-11-01

    Biofilm formation is one of the most important attributes for virulence in Candida species and contributes to increased resistance to antifungal drugs and host immune mechanisms. These features have led to the development of several methodologies to reproduce a sessile community in vitro that can be used to study the development of a biofilm, its interaction with other microorganisms and the environment, and its susceptibility to available antifungal agents and also to search for new therapy strategies. The purpose of this review is to describe the most commonly used methods to study Candida biofilms in vitro, to discuss the benefits and limitations of the different methods to induce biofilm formation, and to analyse the architecture, viability and growth kinetics of Candida biofilms.

  6. The Eye Phone Study: reliability and accuracy of assessing Snellen visual acuity using smartphone technology

    PubMed Central

    Perera, C; Chakrabarti, R; Islam, F M A; Crowston, J

    2015-01-01

    Purpose Smartphone-based Snellen visual acuity charts has become popularized; however, their accuracy has not been established. This study aimed to evaluate the equivalence of a smartphone-based visual acuity chart with a standard 6-m Snellen visual acuity (6SVA) chart. Methods First, a review of available Snellen chart applications on iPhone was performed to determine the most accurate application based on optotype size. Subsequently, a prospective comparative study was performed by measuring conventional 6SVA and then iPhone visual acuity using the ‘Snellen' application on an Apple iPhone 4. Results Eleven applications were identified, with accuracy of optotype size ranging from 4.4–39.9%. Eighty-eight patients from general medical and surgical wards in a tertiary hospital took part in the second part of the study. The mean difference in logMAR visual acuity between the two charts was 0.02 logMAR (95% limit of agreement −0.332, 0.372 logMAR). The largest mean difference in logMAR acuity was noted in the subgroup of patients with 6SVA worse than 6/18 (n=5), who had a mean difference of two Snellen visual acuity lines between the charts (0.276 logMAR). Conclusion We did not identify a Snellen visual acuity app at the time of study, which could predict a patients standard Snellen visual acuity within one line. There was considerable variability in the optotype accuracy of apps. Further validation is required for assessment of acuity in patients with severe vision impairment. PMID:25931170

  7. Reliability study on positive bias temperature instability in SiC MOSFETs by fast drain current measurement

    NASA Astrophysics Data System (ADS)

    Okunishi, Takuma; Hisada, Kenichi; Toyoda, Hisashi; Yamamoto, Yoichi; Arai, Koichi; Yamashita, Yasunori; Yamazaki, Koichi; Nara, Shunji

    2017-04-01

    The gate threshold voltage (V th) shift under positive gate bias stress is one of the most important reliability concerns in silicon carbide metal–oxide–semiconductor field effect transistors (SiC MOSFETs). Because dynamic recovery is observed as soon as the gate bias stress is removed, it is remarkably difficult to accurately evaluate V th shifts. Many studies have focused on how to evaluate V th shifts of SiC MOSFETs under positive gate bias stress. In this study, this issue is investigated by introducing a fast measurement technique. We show that the measured V th shift is modified to take the V th recovery term into consideration. Furthermore, we show that the V th shift is a saturation phenomenon and that the maximum V th shift can be predicted using an electron capture and emission model.

  8. Reliability and validity of a telephone questionnaire for estimating lifetime personal sun exposure in epidemiologic studies.

    PubMed

    Kricker, Anne; Vajdic, Claire M; Armstrong, Bruce K

    2005-10-01

    Our Australia-wide case-control study of ocular melanoma diagnosed in 1996 to 1997 needed a short telephone interview on sun exposure. We constructed one by examining data from 700 controls ages 40 to 64 years in the Geraldton Skin Cancer Survey in 1988; they had answered a "whole-of-life" questionnaire in a face-to-face interview. Sun exposure in their first 4 decade years of age best predicted their lifetime annual average sun exposure, so the shortened questionnaire asked about sun exposure in these 4 decade years only. Retesting 60 participants 1 year later with the whole-of-life questionnaire gave an intraclass correlation coefficient of 0.65 (95% confidence interval, 0.48-0.78) for ranked total sun exposure between the two interviews; the intraclass correlation coefficient was higher in men (0.73) than in women (0.54). Correlations were also high between parallel measurements of sun exposure on working days in the decade years and in outdoor occupations throughout life in the telephone interview of the ocular melanoma study (Spearman's R = 0.75) and in another study of non-Hodgkin's lymphoma (R = 0.71). Agreement between simultaneous parallel measures of total exposure (nonworking + working day and recreational + occupational exposure) was slightly weaker and of nonworking day and recreational exposure much weaker. Occupational exposure in women was much less strongly correlated with total exposure than it was in men possibly because of their frequently combined work and family roles, which the questionnaires did not try to separate. Research is needed into how this might be done to improve sun exposure measurement in women.

  9. How Reliable Are Sino-Nasal Cell Lines for Studying the Pathophysiology of Chronic Rhinosinusitis?

    PubMed Central

    Suwara, Monika I.; Borthwick, Lee A.; Wilson, Janet A.; Mann, Derek A.; Fisher, Andrew J.

    2015-01-01

    Background: Well-characterized cell lines represent useful scientific tools to study the pathophysiology of human disease. Chronic rhinosinusitis (CRS) is a very common condition, though the number of CRS cell lines is limited, as are data showing how closely they resemble primary cells. Methodology: Searches for available human cell lines were performed using the American Type Culture Collection (ATCC) and European Collection of Cell Cultures (ECACC). Identified cells were cultured and characterized with tinctorial and immunohistochemical staining and ELISA to assess their response to common, disease-relevant inflammatory stimuli. Carefully phenotyped CRS patients were recruited with informed consent. Primary nasal epithelial cell (PNEC) brushings were harvested, cultured, and compared to the available cell lines. Results: Searches identified 1 relevant CRS sino-nasal cell line, RPMI 2650. Cultured PNECs showed strong expression of epithelial markers while being negative for mesenchymal markers. However, RPMI 2650 cells show an atypical mixed epithelial/mesenchymal phenotype. When stimulated by pro-inflammatory ligands, PNECs responded in a dose-dependent manner, whereas RPMI 2650 cells showed limited response. Conclusions: The number and availability of cell lines to study the pathophysiology of CRS greatly underrepresent the disease burden. Additionally, the sole commercially available cell line appears to have a different phenotype and behavior to primary patient-derived cells. The development of further reproducible cell lines would be beneficial in our understanding of CRS. PMID:25539661

  10. Is Leadership a Reliable Concept in Animals? An Empirical Study in the Horse

    PubMed Central

    Bourjade, Marie; Thierry, Bernard; Hausberger, Martine; Petit, Odile

    2015-01-01

    Leadership is commonly invoked when accounting for the coordination of group movements in animals, yet it remains loosely defined. In parallel, there is increased evidence of the sharing of group decisions by animals on the move. How leadership integrates within this recent framework on collective decision-making is unclear. Here, we question the occurrence of leadership in horses, a species in which this concept is of prevalent use. The relevance of the three main definitions of leadership – departing first, walking in front travel position, and eliciting the joining of mates – was tested on the collective movements of two semi-free ranging groups of Przewalski horses (Equus ferus przewalskii). We did not find any leader capable of driving most group movements or recruiting mates more quickly than others. Several group members often displayed pre-departure behaviours at the same time, and the simultaneous departure of several individuals was common. We conclude that the decision-making process was shared by several group members a group movement (i.e., partially shared consensus) and that the leadership concept did not help to depict individual departure and leading behaviour across movements in both study groups. Rather, the different proxies of leadership produced conflicting information about individual contributions to group coordination. This study discusses the implications of these findings for the field of coordination and decision-making research. PMID:26010442

  11. Is leadership a reliable concept in animals? An empirical study in the horse.

    PubMed

    Bourjade, Marie; Thierry, Bernard; Hausberger, Martine; Petit, Odile

    2015-01-01

    Leadership is commonly invoked when accounting for the coordination of group movements in animals, yet it remains loosely defined. In parallel, there is increased evidence of the sharing of group decisions by animals on the move. How leadership integrates within this recent framework on collective decision-making is unclear. Here, we question the occurrence of leadership in horses, a species in which this concept is of prevalent use. The relevance of the three main definitions of leadership--departing first, walking in front travel position, and eliciting the joining of mates--was tested on the collective movements of two semi-free ranging groups of Przewalski horses (Equus ferus przewalskii). We did not find any leader capable of driving most group movements or recruiting mates more quickly than others. Several group members often displayed pre-departure behaviours at the same time, and the simultaneous departure of several individuals was common. We conclude that the decision-making process was shared by several group members a group movement (i.e., partially shared consensus) and that the leadership concept did not help to depict individual departure and leading behaviour across movements in both study groups. Rather, the different proxies of leadership produced conflicting information about individual contributions to group coordination. This study discusses the implications of these findings for the field of coordination and decision-making research.

  12. On a simulation study for reliable and secured smart grid communications

    NASA Astrophysics Data System (ADS)

    Mallapuram, Sriharsha; Moulema, Paul; Yu, Wei

    2015-05-01

    Demand response is one of key smart grid applications that aims to reduce power generation at peak hours and maintain a balance between supply and demand. With the support of communication networks, energy consumers can become active actors in the energy management process by adjusting or rescheduling their electricity usage during peak hours based on utilities pricing incentives. Nonetheless, the integration of communication networks expose the smart grid to cyber-attacks. In this paper, we developed a smart grid simulation test-bed and designed evaluation scenarios. By leveraging the capabilities of Matlab and ns-3 simulation tools, we conducted a simulation study to evaluate the impact of cyber-attacks on demand response application. Our data shows that cyber-attacks could seriously disrupt smart grid operations, thus confirming the need of secure and resilient communication networks for supporting smart grid operations.

  13. Reliability studies on NPN RF power transistors under swift heavy ion irradiation

    NASA Astrophysics Data System (ADS)

    Pushpa, N.; Praveen, K. C.; Gnana Prakash, A. P.; Naik, P. S.; Cressler, John D.; Gupta, S. K.; Revannasiddaiah, D.

    2012-02-01

    NPN RF power transistors were irradiated with 140 MeV Si 10+ ions, 100 MeV F 8+ ions, 50 MeV Li 3+ ions and Co-60 gamma radiation in the dose range from 100 krad to 100 Mrad. The transistor characteristics are studied before and after irradiation from which the parameters such as Gummel characteristics, excess base current (Δ IB = IBpost - IBpre), dc current gain ( hFE), transconductance ( gm) and collector-saturation current ( ICSat) are determined. The degradation observed in the electrical characteristics is almost the same for different types of ion irradiated NPN RF power transistors with similar total doses although there is a large difference in the linear energy transfer (LET) of the ions. Further, it was observed more degradation in DC I- V characteristics of ion irradiated devices than the Co-60 gamma irradiated devices for higher doses.

  14. Oxidization of squalene, a human skin lipid: a new and reliable marker of environmental pollution studies.

    PubMed

    Pham, D-M; Boussouira, B; Moyal, D; Nguyen, Q L

    2015-08-01

    A review of the oxidization of squalene, a specific human compound produced by the sebaceous gland, is proposed. Such chemical transformation induces important consequences at various levels. Squalene by-products, mostly under peroxidized forms, lead to comedogenesis, contribute to the development of inflammatory acne and possibly modify the skin relief (wrinkling). Experimental conditions of oxidation and/or photo-oxidation mechanisms are exposed, suggesting that they could possibly be bio-markers of atmospheric pollution upon skin. Ozone, long UVA rays, cigarette smoke… are shown powerful oxidizing agents of squalene. Some in vitro, ex vivo and in vivo testings are proposed as examples, aiming at studying ingredients or products capable of boosting or counteracting such chemical changes that, globally, bring adverse effects to various cutaneous compartments.

  15. Relatively Permanent Pigmented or Vascular Skin Marks for Identification: A Pilot Reliability Study.

    PubMed

    Nurhudatiana, Arfika; Kong, Adams Wai-Kin; Craft, Noah; Tey, Hong Liang

    2016-01-01

    In child sexual exploitation offenses, the collected evidence images often show the skin of nonfacial body parts of the criminals and victims. For identification in this scenario, "relatively permanent pigmented or vascular skin marks," abbreviated as RPPVSM, were recently introduced as the basis for a novel biometric trait. This pilot study evaluated the interexaminer variability of RPPVSM identification. Four dermatology physicians were recruited to examine RPPVSM from 75 skin images collected from a total of 51 Caucasian and Asian subjects. The images were separated into 50 reference ("suspect") images and 25 evaluation ("evidence") images. The examiners were asked to perform identification by annotating RPPVSM in each of the 25 evaluation images and matching them with the reference images. The rate of misidentification was 0% while the mean rate at which examiners failed to find a match was 6%, indicating the potential of dermatology physicians performing the role of RPPVSM examiners.

  16. Do you see what I see? A study about the interrater reliability in art therapy.

    PubMed

    Eitel, Karen; Szkura, Lubow; Pokorny, Dan; von Wietersheim, Joern

    2008-03-01

    There are many clinical reports on art therapy, but there are few data from experimental research. The main goal of this study was to investigate the interrater agreement of 86 raters who evaluated a picture created during an art therapy session. This rating was based on formal (color, lines, shapes) and contextual criteria. The resulting interrater agreement was not satisfying (intraclass correlation coefficient = 0.18-0.52). The authors also address the question of whether raters are able to determine which picture was created at the beginning of the art therapy and which was created at the end. On the basis of the examination of five sets of pictures, it became apparent that they were not able to do so.

  17. Characterization of flaws in a tube bundle mock-up for reliability studies

    SciTech Connect

    Kupperman, D.S.; Bakhtiari, S.

    1997-02-01

    As part of an assessment of in-service inspection of steam generator tubes, the authors will assemble a steam generator mock-up for round robin studies and use as a test bed in evaluating emerging technologies. Progress is reported on the characterization of flaws that will be part of the mock-up. Eddy current and ultrasonic techniques are being evaluated as a means to characterize the flaws in the mock-up tubes before final assembly. Twenty Inconel 600 tubes with laboratory-grown cracks, typical of those to be used in the mock-up, were provided by Pacific Northwest National Laboratory for laboratory testing. After the tubes were inspected with eddy current and ultrasonic techniques, they were destructively analyzed to establish the actual depths, lengths, and profiles of the cracks. The analysis of the results will allow the best techniques to be used for characterizing the flaws in the mock-up tubes.

  18. Reliability of information-based integration of EEG and fMRI data: a simulation study.

    PubMed

    Assecondi, Sara; Ostwald, Dirk; Bagshaw, Andrew P

    2015-02-01

    Most studies involving simultaneous electroencephalographic (EEG) and functional magnetic resonance imaging (fMRI) data rely on the first-order, affine-linear correlation of EEG and fMRI features within the framework of the general linear model. An alternative is the use of information-based measures such as mutual information and entropy, which can also detect higher-order correlations present in the data. The estimate of information-theoretic quantities might be influenced by several parameters, such as the numerosity of the sample, the amount of correlation between variables, and the discretization (or binning) strategy of choice. While these issues have been investigated for invasive neurophysiological data and a number of bias-correction estimates have been developed, there has been no attempt to systematically examine the accuracy of information estimates for the multivariate distributions arising in the context of EEG-fMRI recordings. This is especially important given the differences between electrophysiological and EEG-fMRI recordings. In this study, we drew random samples from simulated bivariate and trivariate distributions, mimicking the statistical properties of EEG-fMRI data. We compared the estimated information shared by simulated random variables with its numerical value and found that the interaction between the binning strategy and the estimation method influences the accuracy of the estimate. Conditional on the simulation assumptions, we found that the equipopulated binning strategy yields the best and most consistent results across distributions and bias correction methods. We also found that within bias correction techniques, the asymptotically debiased (TPMC), the jackknife debiased (JD), and the best upper bound (BUB) approach give similar results, and those are consistent across distributions.

  19. Emotion Recognition Ability Test Using JACFEE Photos: A Validity/Reliability Study of a War Veterans' Sample and Their Offspring.

    PubMed

    Castro-Vale, Ivone; Severo, Milton; Carvalho, Davide; Mota-Cardoso, Rui

    2015-01-01

    Emotion recognition is very important for social interaction. Several mental disorders influence facial emotion recognition. War veterans and their offspring are subject to an increased risk of developing psychopathology. Emotion recognition is an important aspect that needs to be addressed in this population. To our knowledge, no test exists that is validated for use with war veterans and their offspring. The current study aimed to validate the JACFEE photo set to study facial emotion recognition in war veterans and their offspring. The JACFEE photo set was presented to 135 participants, comprised of 62 male war veterans and 73 war veterans' offspring. The participants identified the facial emotion presented from amongst the possible seven emotions that were tested for: anger, contempt, disgust, fear, happiness, sadness, and surprise. A loglinear model was used to evaluate whether the agreement between the intended and the chosen emotions was higher than the expected. Overall agreement between chosen and intended emotions was 76.3% (Cohen kappa = 0.72). The agreement ranged from 63% (sadness expressions) to 91% (happiness expressions). The reliability by emotion ranged from 0.617 to 0.843 and the overall JACFEE photo set Cronbach alpha was 0.911. The offspring showed higher agreement when compared with the veterans (RR: 41.52 vs 12.12, p < 0.001), which confirms the construct validity of the test. The JACFEE set of photos showed good validity and reliability indices, which makes it an adequate instrument for researching emotion recognition ability in the study sample of war veterans and their respective offspring.

  20. Emotion Recognition Ability Test Using JACFEE Photos: A Validity/Reliability Study of a War Veterans' Sample and Their Offspring

    PubMed Central

    Castro-Vale, Ivone; Severo, Milton; Carvalho, Davide; Mota-Cardoso, Rui

    2015-01-01

    Emotion recognition is very important for social interaction. Several mental disorders influence facial emotion recognition. War veterans and their offspring are subject to an increased risk of developing psychopathology. Emotion recognition is an important aspect that needs to be addressed in this population. To our knowledge, no test exists that is validated for use with war veterans and their offspring. The current study aimed to validate the JACFEE photo set to study facial emotion recognition in war veterans and their offspring. The JACFEE photo set was presented to 135 participants, comprised of 62 male war veterans and 73 war veterans’ offspring. The participants identified the facial emotion presented from amongst the possible seven emotions that were tested for: anger, contempt, disgust, fear, happiness, sadness, and surprise. A loglinear model was used to evaluate whether the agreement between the intended and the chosen emotions was higher than the expected. Overall agreement between chosen and intended emotions was 76.3% (Cohen kappa = 0.72). The agreement ranged from 63% (sadness expressions) to 91% (happiness expressions). The reliability by emotion ranged from 0.617 to 0.843 and the overall JACFEE photo set Cronbach alpha was 0.911. The offspring showed higher agreement when compared with the veterans (RR: 41.52 vs 12.12, p < 0.001), which confirms the construct validity of the test. The JACFEE set of photos showed good validity and reliability indices, which makes it an adequate instrument for researching emotion recognition ability in the study sample of war veterans and their respective offspring. PMID:26147938