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Sample records for subscapular skinfold thicknesses

  1. Triceps and Subscapular Skinfold Thickness Percentiles and Cut-Offs for Overweight and Obesity in a Population-Based Sample of Schoolchildren and Adolescents in Bogota, Colombia

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    Robinson Ramírez-Vélez

    2016-09-01

    Full Text Available The assessment of skinfold thickness is an objective measure of adiposity. The aims of this study were to establish Colombian smoothed centile charts and LMS L (Box–Cox transformation, M (median, and S (coefficient of variation tables for triceps, subscapular, and triceps + subscapular skinfolds; appropriate cut-offs were selected using receiver operating characteristic (ROC analysis based on a population-based sample of children and adolescents in Bogotá, Colombia. A cross-sectional study was conducted in 9618 children and adolescents (55.7% girls; age range of 9–17.9 years. Triceps and subscapular skinfold measurements were obtained using standardized methods. We calculated the triceps + subscapular skinfold (T + SS sum. Smoothed percentile curves for triceps and subscapular skinfold thickness were derived using the LMS method. ROC curve analyses were used to evaluate the optimal cut-off point of skinfold thickness for overweight and obesity, based on the International Obesity Task Force definitions. Subscapular and triceps skinfolds and T + SS were significantly higher in girls than in boys (p < 0.001. The ROC analysis showed that subscapular and triceps skinfolds and T + SS have a high discriminatory power in the identification of overweight and obesity in the sample population in this study. Our results provide sex- and age-specific normative reference standards for skinfold thickness values from a population from Bogotá, Colombia.

  2. Triceps and Subscapular Skinfold Thickness Percentiles and Cut-Offs for Overweight and Obesity in a Population-Based Sample of Schoolchildren and Adolescents in Bogota, Colombia

    Science.gov (United States)

    Ramírez-Vélez, Robinson; López-Cifuentes, Mario Ferney; Correa-Bautista, Jorge Enrique; González-Ruíz, Katherine; González-Jiménez, Emilio; Córdoba-Rodríguez, Diana Paola; Vivas, Andrés; Triana-Reina, Hector Reynaldo; Schmidt-RioValle, Jacqueline

    2016-01-01

    The assessment of skinfold thickness is an objective measure of adiposity. The aims of this study were to establish Colombian smoothed centile charts and LMS L (Box–Cox transformation), M (median), and S (coefficient of variation) tables for triceps, subscapular, and triceps + subscapular skinfolds; appropriate cut-offs were selected using receiver operating characteristic (ROC) analysis based on a population-based sample of children and adolescents in Bogotá, Colombia. A cross-sectional study was conducted in 9618 children and adolescents (55.7% girls; age range of 9–17.9 years). Triceps and subscapular skinfold measurements were obtained using standardized methods. We calculated the triceps + subscapular skinfold (T + SS) sum. Smoothed percentile curves for triceps and subscapular skinfold thickness were derived using the LMS method. ROC curve analyses were used to evaluate the optimal cut-off point of skinfold thickness for overweight and obesity, based on the International Obesity Task Force definitions. Subscapular and triceps skinfolds and T + SS were significantly higher in girls than in boys (p Colombia. PMID:27669294

  3. Triceps and Subscapular Skinfold Thickness Percentiles and Cut-Offs for Overweight and Obesity in a Population-Based Sample of Schoolchildren and Adolescents in Bogota, Colombia.

    Science.gov (United States)

    Ramírez-Vélez, Robinson; López-Cifuentes, Mario Ferney; Correa-Bautista, Jorge Enrique; González-Ruíz, Katherine; González-Jiménez, Emilio; Córdoba-Rodríguez, Diana Paola; Vivas, Andrés; Triana-Reina, Hector Reynaldo; Schmidt-RioValle, Jacqueline

    2016-09-24

    The assessment of skinfold thickness is an objective measure of adiposity. The aims of this study were to establish Colombian smoothed centile charts and LMS L (Box-Cox transformation), M (median), and S (coefficient of variation) tables for triceps, subscapular, and triceps + subscapular skinfolds; appropriate cut-offs were selected using receiver operating characteristic (ROC) analysis based on a population-based sample of children and adolescents in Bogotá, Colombia. A cross-sectional study was conducted in 9618 children and adolescents (55.7% girls; age range of 9-17.9 years). Triceps and subscapular skinfold measurements were obtained using standardized methods. We calculated the triceps + subscapular skinfold (T + SS) sum. Smoothed percentile curves for triceps and subscapular skinfold thickness were derived using the LMS method. ROC curve analyses were used to evaluate the optimal cut-off point of skinfold thickness for overweight and obesity, based on the International Obesity Task Force definitions. Subscapular and triceps skinfolds and T + SS were significantly higher in girls than in boys (p Colombia.

  4. SUBSCAPULAR AND TRICEPS SKINFOLDS REFERENCE VALUES OF HISPANIC AMERICAN CHILDREN AND ADOLESCENTS AND THEIR COMPARISON WITH THE REFERENCE OF CENTERS FOR DISEASE CONTROL AND PREVENTION (CDC).

    Science.gov (United States)

    Marrodán Serrano, María Dolores; González-Montero de Espinosa, Marisa; Herráez, Ángel; Alfaro, Emma Laura; Felipe Bejarano, Ignacio; Carmenate, María Margarita; Prado, Consuelo; Beatriz Lomaglio, Delia; López-Ejeda, Noemí; Martínez, Antonio; Mesa, María Soledad; Méndez Pérez, Betty; Meléndez, Juana María; Moreno Romero, Susana; Pacheco, Jose Luis; Vázquez, Vanessa; Dipierri, José E

    2015-12-01

    the assessment of the skinfold thickness is an objective measure of adiposity. Therefore, it is a useful tool for nutritional diagnosis and prevention of metabolic risk associated with excess fat in chilhood and adolescence. to provide percentiles of subscapular and triceps skinfolds for Hispanic American schoolchildren and compare them with those published by the Centers for Disease Control and Prevention (CDC) from United States, that it have been commonly used as a reference in most of these countries. subscapular and triceps skinfolds were measured in 9.973 schoolchildren 4-19 aged from Spain, Argentina, Cuba, Venezuela and Mexico with Holtain caliper with 0.2 mm accuracy. Percentiles were obtained with the LMS statistical method and were presented in tables divided in stages of 6 months and in curves graphics. The difference between Hispanic American and CDC mean values were provided for P3, P50 and P97 in mm and also were graphically represented. skinfolds measurements obviously increased with age in both sexes but, in boys, this increase is much more marked in highest percentiles between 8 and 13 years; this maximum is reached earlier than what occurs in CDC reference. In both sexes, all percentiles analized in Hispanic American schoolchildren were higher than the CDC reference except P97 up to 10 or 13 years that was notably smaller. the skinfolds percentiles of Hispanic American children and adolescents differ from CDC that are usually used as reference. The values of subscapular and triceps skinfolds provided in this study, could be applied to populations of a similar ethnic background, especially in comparative studies of body composition. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  5. Static skinfold thickness in African newborns as an index of fetal nutritional assessment.

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    Tongo, Olukemi O; Ajayi, Samuel O; Ogunbosi, Babatunde O; Orimadegun, Adebola E; Akinyinka, Olusegun O

    2013-08-01

    Fetal malnutrition (FM) has grave implications for the neonate and is reliably assessed by the CANSCORE which is time-consuming. Static skinfold thickness, a measure of adiposity, is a validated method of assessing malnutrition in older children. To establish if static skinfold measurements in neonates can serve as a reliable measure of FM. To compare static skinfold thickness measurements in neonates using the CANSCORE for the identification of FM. 252 consecutive term neonates delivered at University College Hospital, Ibadan, Nigeria had their CANSCOREs and static skinfold thickness measured within 24 hours of delivery. Using correlation and linear regression analysis, static skinfold thickness cut-off points for FM were determined using a reference CANSCORE of FM was 20.2% and 26.2% using the CANSCORE and the sum of five skinfold thickness measurements, respectively. The mean (SD) skinfold thicknesses were triceps 3.91 mm (0.74), biceps 2.84 mm (0.55), subscapular 3.79 mm (0.91), supra-iliac 2.64 mm (0.62), quadriceps 4.43 mm (1) and the sum of all measurements 17.61 mm (3.16). All the skinfold thickness measurements correlated significantly with the CANSCORE, but the sum of the five had the best correlation. The quadriceps had the highest specificity of 85.6% and lowest sensitivity of 54.9%, while the sum of all had a sensitivity of 66.7% and specificity of 84.0%. The sum of all five skinfold measurements might be a useful screening tool for FM in view of its objectivity, convenience and simplicity, but it is not sufficiently sensitive or specific to replace the CANSCORE in the identification of FM in neonates.

  6. Detecting overweight and obesity among young Syrian boys based on skinfold thickness

    OpenAIRE

    Al-Bachir Mahfouz; Ahhmad Hussam

    2016-01-01

    There is no data on the prevalence of overweight and obesity in young Syrian boys. Therefore, the present study aimed to provide baseline and reference data on the prevalence of overweight and obesity among young Syrian boys using skin-fold thickness measurements and deuterium dilution (DD) as a reference method. The sample of 2470 healthy Syrian 18- to 19-year-old boys were enrolled in this study. SFTs were measured at the biceps (B), triceps (T), subscapular (SI) and suprailiac locations (S...

  7. Changes in single skinfold thickness in 100 km ultramarathoners

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    Knechtle B

    2012-10-01

    Full Text Available Beat Knechtle,1,2 Sabrina Baumgartner,1 Patrizia Knechtle,2 Christoph Alexander Rüst,1 Thomas Rosemann,1 Raúl Bescós31Institute of General Practice and Health Services Research, University of Zurich, Zurich; 2Gesundheitszentrum St Gallen, St Gallen, Switzerland; 3National Institute of Physical Education, Barcelona, SpainBackground: Changes in single skinfold thickness and body fat have been investigated in ultraswimmers and ultracyclists, but not in ultrarunners. The present study investigated the changes in single skinfold thickness during a 100 km ultramarathon.Methods: Firstly, we investigated associations between prerace preparation and prerace body composition and, secondly, changes in single skinfold thickness during a 100 km ultramarathon in 219 male ultramarathoners. Changes in fat mass and skeletal muscle were estimated using anthropometric methods.Results: Kilometers run weekly prerace and running speed during training were negatively associated with all skinfold thicknesses (P < 0.05 except for the front thigh skinfold. During the race, skinfold thickness at the pectoral (−0.1%, suprailiac (−1.8%, and calf (−0.8% sites decreased (P < 0.05. The subjects lost 1.9 ± 1.4 kg of body mass (P < 0.001, 0.7 ± 1.0 kg of estimated skeletal muscle mass (P < 0.001, and 0.2 ± 1.3 kg of estimated fat mass (P < 0.05. The decrease in body mass was positively related to the decrease in both estimated skeletal muscle mass (r = 0.21, P = 0.0017 and estimated fat mass (r = 0.41, P < 0.0001.Conclusion: Firstly, prerace fat mass and prerace skinfold thickness were associated with both volume and speed in running training. Secondly, during the ultramarathon, skinfold thickness decreased at the pectoral, suprailiac, and calf sites, but not at the thigh site. Percent decreases in skinfold thickness for ultrarunners was lower than the percent decreases in skinfold thickness reported for ultraswimmers and ultracyclists.Keywords: endurance, athlete

  8. Estimation of body fat in Pakistani adult: A comparison of equations based upon skinfold thickness measurements

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    Naz, Hafeeza; Mushtaq, Kinza; Butt, Bilal Azeem; Khawaja, Khadija Irfan

    2017-01-01

    Objective: To compare three different body fats estimation equations using skin fold measurements with bioelectrical impedance analysis. Methods: A total of 130 subjects were included from Department of Endocrinology and Metabolism, Services Hospital, Lahore from 1st April 2016 to 30th Sep. 2016. The triceps, biceps, subscapular, chest, thigh, abdominal, suprailiac skinfold thickness of the subjects was measured with skin-fold calipers (Harpenden) on non-dominant side. The percentage fat mass (%FM) predicted by using each skin-fold-thickness equations namely Durnin & Womersley, Jackson & Pollock and Sloan was compared with %FM measured using a bioelectrical impedance analyzer (BIA). Results: The mean age of subjects was 48.75±10.7 years, mean BMI was 29.08±6.09 kg/m2. The mean %FM calculated by Durnin & Womersley (32.408±0.584), Jackson & Pollock (24.658±0.527), Sloan (20.40±0.545). The %FM by BIA was 38.182±0.529. All three equations showed positive correlation but underestimated %FM as compared to BIA. Conclusion: All three BF estimation equations underestimate body fat percentage compared to BIA. Among the three, Durnin & Womersley equation shows best positive correlation and hence it can be used for estimation of percentage fat mass as an alternate to BIA. PMID:28811785

  9. Estimating body fat in African American and white adolescent girls: a comparison of skinfold-thickness equations with a 4-compartment criterion model.

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    Wong, W W; Stuff, J E; Butte, N F; Smith, E O; Ellis, K J

    2000-08-01

    Although skinfold-thickness equations are widely used to estimate body fat, their accuracy in a biracial population of female adolescents has not been established. We undertook this study to determine the agreement between 8 widely used skinfold-thickness equations and a 4-compartment criterion model in predicting the percentage body fat of 72 white and 40 African American girls aged 13.0 +/- 1.9 y. The biceps, triceps, suprailiac, subscapular, thigh, calf, and abdominal skinfold thicknesses of the subjects were measured with skinfold calipers and the buttocks circumference with a metal tape. The percentage fat mass (%FM) predicted by using each skinfold-thickness equation was compared with the criterion value calculated by the 4-compartment model on the basis of measurements of body density, body water, and bone mineral content. When the racial groups were analyzed separately, the Bland-Altman analysis indicated that the quadratic equations agreed most closely with the 4-compartment model's measurement of %FM. Agreement of the other equations varied with body fatness. The quadratic equation of Slaughter et al is recommended for population studies in female adolescents because of its accuracy and simplicity. However, an individual %FM can be over- or underestimated by approximately 10% when this skinfold-thickness equation is used.

  10. A comparison of the Slaughter skinfold-thickness equations and BMI in predicting body fatness and cardiovascular disease risk factor levels in children.

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    Freedman, David S; Horlick, Mary; Berenson, Gerald S

    2013-12-01

    Although estimation of percentage body fat with the Slaughter skinfold-thickness equations (PBF(Slaughter)) is widely used, the accuracy of this method has not been well studied. The objective was to determine the accuracy of the Slaughter skinfold-thickness equations. We compared agreement between PBF(Slaughter) and estimations derived from dual-energy X-ray absorptiometry (PBF(DXA)) in 1169 children in the Pediatric Rosetta Body Composition Project and the relation to cardiovascular disease risk factors, as compared with body mass index (BMI), in 6725 children in the Bogalusa Heart Study. PBF(Slaughter) was highly correlated (r = 0.90) with PBF(DXA), but it markedly overestimated levels of PBF(DXA) in children with large skinfold thicknesses. In the 65 boys with a sum of skinfold thicknesses (subscapular- plus triceps-skinfold thicknesses) ≥ 50 mm, PBF(Slaughter) overestimated PBF(DXA) by 12 percentage points. The comparable overestimation in girls with a high skinfold sum was 6 percentage points. We also found that, after adjustment for sex and age, BMI showed slightly stronger associations with lipid, lipoprotein, insulin, and blood pressure values than did PBF(Slaughter). These results indicate that PBF(Slaughter), which was developed among a group of much thinner children and adolescents, is fairly accurate among nonobese children, but markedly overestimates the body fatness of children who have thick skinfold thicknesses. Furthermore, PBF(Slaughter) has no advantage over sex- and age-adjusted BMIs at identifying children who are at increased risk of cardiovascular disease based on lipid, lipoprotein, insulin, and blood pressure values.

  11. Skinfold Thickness at 8 Common Cryotherapy Sites in Various Athletic Populations

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    Jutte, Lisa S.; Hawkins, Jeremy; Miller, Kevin C.; Long, Blaine C.; Knight, Kenneth L.

    2012-01-01

    Context: Researchers have observed slower cooling rates in thigh muscle with greater overlying adipose tissue, suggesting that cryotherapy duration should be based on the adipose thickness of the treatment site. Skinfold data do not exist for other common cryotherapy sites, and no one has reported how those skinfolds might vary because of physical activity level or sex. Objective: To determine the variability in skinfold thickness among common cryotherapy sites relative to sex and activity level (National Collegiate Athletic Association Division I athletes, recreationally active college athletes). Design: Descriptive laboratory study. Setting: Field. Patients or Other Participants: Three hundred eighty-nine college students participated; 196 Division I athletes (157 men, 39 women) were recruited during preseason physicals, and 193 recreationally active college athletes (108 men, 85 women) were recruited from physical education classes. Intervention(s): Three skinfold measurements to within 1 mm were taken at 8 sites (inferior angle of the scapula, middle deltoid, ulnar groove, midforearm, midthigh, medial collateral ligament, midcalf, and anterior talofibular ligament [ATF]) using Lange skinfold calipers. Main Outcome Measure(s): Skinfold thickness in millimeters. Results: We noted interactions among sex, activity level, and skinfold site. Male athletes had smaller skinfold measurements than female athletes at all sites except the ATF, scapula, and ulnar groove (F7,2702 = 69.85, P cryotherapy treatment sites varied based on level of physical activity and sex. Therefore, clinicians should measure skinfold thickness to determine an appropriate cryotherapy duration. PMID:22488282

  12. Detecting overweight and obesity among young Syrian boys based on skinfold thickness

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    Al-Bachir Mahfouz

    2016-03-01

    Full Text Available There is no data on the prevalence of overweight and obesity in young Syrian boys. Therefore, the present study aimed to provide baseline and reference data on the prevalence of overweight and obesity among young Syrian boys using skin-fold thickness measurements and deuterium dilution (DD as a reference method. The sample of 2470 healthy Syrian 18- to 19-year-old boys were enrolled in this study. SFTs were measured at the biceps (B, triceps (T, subscapular (SI and suprailiac locations (SS were done and validated using the DD technique as a reference method. Receiver operating characteristics (ROC curve was drawn to determine appropriate cut-off points of the Σ2 limb SFT (T+B, Σ2 trunk SFT (SI+SS, Σ4 SFT (T+B+SI+SS and Log Σ4 SFT for defining overweight and obesity. The overall prevalence of overweight and obesity in young Syrian boys, based on biceps SFT, triceps SFT, subscapular SFT, suprailiac SFT, Σ2 limb SFT, Σ2 trunk SFT, Σ4 SFT, logarithm Σ4 SFT, and DDT were 35.3%, 32%, 31.6%, 14.8%, 32.9%, 26.6%, 28.1%, 24.1%, 46.5%, respectively. Strongly positive correlation was found between SFT and total body fat in adolescents. For diagnosing overweight on the basis of Σ2 limb SFT, Σ2 trunk SFT, Σ4 SFT and logarithm Σ4 SFT, we propose the following cut-off points: 17.25 mm, 23.50 mm, 39.25 mm and 1.60, respectively. To predict obesity, Σ2 limb SFT, Σ2 trunk SFT, Σ4 SFT and logarithm Σ4 SFT threshold were increased to 23.25 mm, 32.50 mm, 55.25 and 1.75, respectively. Basing on SFT clearly leads to underestimates of the prevalence of weight problems among young boys. SFT measurement screen missed 11.2 to 31.7% of overall overweight and obesity cases.

  13. Skin-fold thickness and race performance in male mountain ultra-marathoners

    OpenAIRE

    Knechtle, Beat; Rosemann, Thomas

    2009-01-01

    Recent studies showed in high level runners both an association between selected skin-fold thicknesses at the lower limb and running performance and between thickness of skin-fold and training. We investigated the association of skin-fold thicknesses with total race time in 25 male mountain ultra-marathoners with 44.5 (7.0) years, 73.0 (7.8) kg body mass, 1.78 (0.07) m body height and a BMI of 22.9 (1.8) kg/m2 in a 7-day mountain ultra-marathon over 350 km with 11,000 m of altitude. The relat...

  14. Detecting overweight and obesity among young Syrian boys based on skinfold thickness

    National Research Council Canada - National Science Library

    Mahfouz Al-Bachir; Hussam Ahhmad

    2016-01-01

    .... Therefore, the present study aimed to provide baseline and reference data on the prevalence of overweight and obesity among young Syrian boys using skin-fold thickness measurements and deuterium dilution (DD...

  15. Assessment and correction of skinfold thickness equations in estimating body fat in children with cerebral palsy

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    GURKA, MATTHEW J; KUPERMINC, MICHELLE N; BUSBY, MARJORIE G; BENNIS, JACEY A; GROSSBERG, RICHARD I; HOULIHAN, CHRISTINE M; STEVENSON, RICHARD D; HENDERSON, RICHARD C

    2010-01-01

    AIM To assess the accuracy of skinfold equations in estimating percentage body fat in children with cerebral palsy (CP), compared with assessment of body fat from dual energy X-ray absorptiometry (DXA). METHOD Data were collected from 71 participants (30 females, 41 males) with CP (Gross Motor Function Classification System [GMFCS] levels I–V) between the ages of 8 and 18 years. Estimated percentage body fat was computed using established (Slaughter) equations based on the triceps and subscapular skinfolds. A linear model was fitted to assess the use of a simple correction to these equations for children with CP. RESULTS Slaughter’s equations consistently underestimated percentage body fat (mean difference compared with DXA percentage body fat −9.6/100 [SD 6.2]; 95% confidence interval [CI] −11.0 to −8.1). New equations were developed in which a correction factor was added to the existing equations based on sex, race, GMFCS level, size, and pubertal status. These corrected equations for children with CP agree better with DXA (mean difference 0.2/100 [SD=4.8]; 95% CI −1.0 to 1.3) than existing equations. INTERPRETATION A simple correction factor to commonly used equations substantially improves the ability to estimate percentage body fat from two skinfold measures in children with CP. PMID:19811518

  16. Nuchal Skinfold Thickness : A Novel Parameter for Assessment of Body Composition in Childhood Craniopharyngioma

    NARCIS (Netherlands)

    Sterkenburg, Anthe S.; Hoffmann, Anika; Reichel, Julia; Lohle, Kristin; Eveslage, Maria; Warmuth-Metz, Monika; Mueller, Hermann L.

    2016-01-01

    Context: Hypothalamic obesity, cardiovascular disease (CVD), and relapse/progression have a major impact on prognosis in childhood-onset craniopharyngioma (CP). We analyzed nuchal skinfold thickness (NST) on magnetic resonance imaging performed for follow-up monitoring as a novel parameter for body

  17. Developing a tool for obtaining maternal skinfold thickness measurements and assessing inter-observer variability among pregnant women who are overweight and obese

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    Kannieappan Lavern M

    2013-02-01

    Full Text Available Abstract Background It is estimated that between 34% and 50% of Australian women entering pregnancy are overweight and obese, which is associated with an increased risk in complications for both the woman and her infant. Current tools used in clinical and research practice for measuring body composition include body mass index (BMI, waist circumference and bioimpedance analysis. Not all of these measures are applicable for use during pregnancy due to a lack of differentiation between maternal and fetal contributions. While skinfold thickness measurement (SFTM is increasingly being used in pregnancy, there is limited data and a lack of a standard tool for its use in overweight and obese pregnant women. Methods We developed a standard tool for evaluating SFTM among women with a BMI ≥ 25 kg/m2. Forty-nine women were measured as part of a prospective cohort study nested within a multicentre randomised controlled trial (The LIMIT Randomised Controlled Trial. Two blinded observers each performed 2 skinfold measurements on the biceps, triceps and subscapular of each woman. Intraclass correlation coefficients (ICC and standard error of measurement (SEM were used to analyse SFTM, body fat percentage (BF% and inter-observer variability. Results The ICC for inter-observer variability in measurements were considered moderate for biceps SFTM (ICC = 0.56 and triceps SFTM (ICC = 0.51; good for subscapular SFTM (ICC = 0.71 and BF% (ICC = 0.74; and excellent for arm circumference (ICC = 0.97. The standard error of measurements ranged from 0.53 cm for arm circumference to 3.58 mm for the subscapular SFTM. Conclusion Our findings indicate that arm circumference and biceps, triceps and subscapular SFTM can be reliably obtained from overweight and obese pregnant women to calculate BF%, using multiple observers, and can be used in a research setting. Trial registration Australian and New Zealand Clinical Trials Registry ACTRN

  18. Skinfold thicknesses method to analyse body fat in hemodialysis patients: comparison with dual energy x-ray absorptiometry

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    Viviane O Leal

    2012-06-01

    Full Text Available Nutritional status is a major determinant of the outcome of hemodialysis (HD patients. While protein wasting is associated with morbidity and mortality, high fat mass and central adiposity is also observed in HD population and, related to metabolic disorders. Therefore, body composition assessment is a key point to provide adequate nutritional care to these patients. In this way, practical and reliable indicators of body composition are needed for clinical purposes. Thus, the objective of this study was to evaluate the use of anthropometry as an alternative to dual energy X-ray absorptiometry (DXA, considered the reference method to evaluate body fat in HD patients. Thirty-nine HD patients (52.7±11.3 years, 24 men, BMI, 23.7±4.0 kg/m2, urea clearance (Kt/Vsp of 1.47±0.22 and 64.1±46.1 months on HD were studied. Percentage of body fat (%BF was performed by DXA scans (Prodigy Advanc Plus, Lunar Corp, Madison, WI, USA and anthropometry (biceps, triceps, subscapular and suprailiac skinfold thicknesses after a HD session. Body density was calculated using the formula of Durnin and Womersley (1974 and the %BF was calculated by Siri´s equation (Siri, 1961. The reference values for %BF were considered (Lohman et al., 1991. The mean of %BF assessed by anthopometry and DXA was 25.2±6.9% and 26.8±8.3% for men and 32.8±6.3% and 31.5±8.7% for women, respectively. The most of HD patients presented high %BF (≥25% for men and ≥32% for women: 59.0% by anthropometry and 56.4% by DXA. The paired analysis showed that the %BF assessment was not different when evaluated by anthropometry or DXA methods (p=0.6. The kappa coefficient between DXA and anthropometry was 0.42 (p<0.0001, which is considered as good correlation between two methods. In conclusion, the simple method of skinfold thicknesses is reliable to assess body fat in HD patients when compared to DXA.

  19. Relationships between neonatal weight, limb lengths, skinfold thicknesses, body breadths and circumferences in an Australian cohort.

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    Emma Pomeroy

    Full Text Available Low birth weight has been consistently associated with adult chronic disease risk. The thrifty phenotype hypothesis assumes that reduced fetal growth impacts some organs more than others. However, it remains unclear how birth weight relates to different body components, such as circumferences, adiposity, body segment lengths and limb proportions. We hypothesized that these components vary in their relationship to birth weight.We analysed the relationship between birth weight and detailed anthropometry in 1270 singleton live-born neonates (668 male from the Mater-University of Queensland Study of Pregnancy (Brisbane, Australia. We tested adjusted anthropometry for correlations with birth weight. We then performed stepwise multiple regression on birth weight of: body lengths, breadths and circumferences; relative limb to neck-rump proportions; or skinfold thicknesses. All analyses were adjusted for sex and gestational age, and used logged data.Circumferences, especially chest, were most strongly related to birth weight, while segment lengths (neck-rump, thigh, upper arm, and especially lower arm and lower leg were relatively weakly related to birth weight, and limb lengths relative to neck-rump length showed no relationship. Skinfolds accounted for 36% of birth weight variance, but adjusting for size (neck-rump, thigh and upper arm lengths, and head circumference, this decreased to 10%. There was no evidence that heavier babies had proportionally thicker skinfolds.Neonatal body measurements vary in their association with birth weight: head and chest circumferences showed the strongest associations while limb segment lengths did not relate strongly to birth weight. After adjusting for body size, subcutaneous fatness accounted for a smaller proportion of birth weight variance than previously reported. While heavier babies had absolutely thicker skinfolds, this was proportional to their size. Relative limb to trunk length was unrelated to birth

  20. Skinfold thickness affects the isometric knee extension torque evoked by Neuromuscular Electrical Stimulation

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    Flávia V. A. Medeiros

    2015-12-01

    Full Text Available BACKGROUND: Subcutaneous adipose tissue may influence the transmission of electrical stimuli through to the skin, thus affecting both evoked torque and comfort perception associated with neuromuscular electrical stimulation (NMES. This could seriously affect the effectiveness of NMES for either rehabilitation or sports purposes. OBJECTIVE: To investigate the effects of skinfold thickness (SFT on maximal NMES current intensity, NMES-evoked torque, and NMES-induced discomfort. METHOD: First, we compared NMES current intensity, NMES-induced discomfort, and NMES-evoked torque between two subgroups of subjects with thicker (n=10; 20.7 mm vs. thinner (n=10; 29.4 mm SFT. Second, we correlated SFT to NMES current intensity, NMES-induced discomfort, and NMES-evoked knee extension torque in 20 healthy women. The NMES-evoked torque was normalized to the maximal voluntary contraction (MVC torque. The discomfort induced by NMES was assessed with a visual analog scale (VAS. RESULTS: NMES-evoked torque was 27.5% lower in subjects with thicker SFT (p=0.01 while maximal current intensity was 24.2% lower in subjects with thinner SFT (p=0.01. A positive correlation was found between current intensity and SFT (r=0.540, p=0.017. A negative correlation was found between NMES-evoked torque and SFT (r=-0.563, p=0.012. No significant correlation was observed between discomfort scores and SFT (rs=0.15, p=0.53. CONCLUSION: These results suggest that the amount of subcutaneous adipose tissue (as reflected by skinfold thickness affected NMES current intensity and NMES-evoked torque, but had no effect on discomfort perception. Our findings may help physical therapists to better understand the impact of SFT on NMES and to design more rational stimulation strategies.

  1. Skinfold thickness versus bioelectrical impedance for the evaluation of body composition in athletes: a critical review

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    Rafael Deminice

    2009-06-01

    Full Text Available Body composition is a determinant factor for performance in different sports modalities. Safe, practical and validated instruments are necessary for the measurement of body composition and for the identification of alterations that occur during the training period. A critical review was performed comparing studies that apply skinfold thickness (SKF and bioelectrical impedance (BIA for the estimation of body composition in athletes. Studies published between 1990 and 2007 available online in the Pubmed, SportDiscus and Scielo databases were reviewed. Seven critical points were evaluated to rate the studies: number of subjects, performance level of the athletes studied, statistical methods applied, number of equations tested, test control, sample control, and gold standard used to compare the data. SKF and BIA present advantages for the assessment of body composition in athletes compared to other methods, such as their easy application, non-invasiveness and relatively low cost. The accuracy and reliability of the results obtained with these methods depend on test conditions, equations selected for data analysis and characteristics of the particular group (sports modality, gender, age and performance level. SKF seems to be a better method to estimate body composition in athletes because of the availability of specific equations for different sports modalities and because of the low sensitivity of BIA in detecting minimal alterations that occur during the training period.

  2. The dynamics of growth of weight, circumferences and skinfolds in distance, velocity and acceleration.

    Science.gov (United States)

    Gasser, T; Ziegler, P; Kneip, A; Prader, A; Molinari, L; Largo, R H

    1993-01-01

    Based on structural average curves of distance, velocity and acceleration, an analysis of the longitudinally assessed growth of weight, arm and calf circumferences and skinfolds (biceps, triceps, suprailiac, subscapular) was undertaken. The data come from the first Zürich longitudinal growth study and represent a normal sample. In addition to a graphic analysis, timing, intensity and duration of the mid-growth spurt (MS) and of the pubertal spurt (PS) are quantified via descriptive parameters of growth. Mechanisms are different and more complex for these variables, in particular for skinfolds, compared to previously studied somatic variables, such as height. Skinfolds showed a rapid decline to a negative velocity minimum in the first year, recovering to a pre-PS fat spurt, earlier and more pronounced for central (suprailiac, subscapular) than for peripheral skinfolds (biceps, triceps). At age of peak height velocity a drop occurred, stronger for boys, followed by a post-PS spurt. A further analysis demonstrates that these ups and downs in skinfold velocity are mainly due to subjects with thick skinfolds. Weight and circumferences show a distinct MS, with sex-independent characteristics and a strong, sex-dependent PS. Weight and even more arm circumference are delayed compared to height in puberty.

  3. Skin-fold thickness, body mass, and obesity indexes and the arterial to skin-surface PO2 gradient.

    Science.gov (United States)

    Rafferty, T D; Morrero, O

    1983-10-01

    Trends in transcutaneous oxygen tension (tcPO2) correlate closely with Pao2 in the absence of circulatory insufficiency. Individual variation, however, in the arterial to skin-surface Po2 gradient (Pao2-tcPo2 gradient) have limited the usefulness of tcPo2 measurements as precise indicators of Pao2. This individual variability in the Pao2-tcPo2 gradient has been speculated as being caused by "skin factors." This study was performed to examine the relationship between skin-fold thickness (triceps and infraclavicular), body mass index, body surface area, and ponderal index and the Pao2-tcPo2 gradient with a view to delineating correction factors that might be useful in increasing the accuracy of tcPo2 as an estimate of the absolute value of the corresponding Pao2. Skin-fold thickness measurements, body mass index, body surface area, and ponderal index were unrelated to the Po2 gradient. This was thought to be primarily due to an inherent inaccuracy of these measurements as indicators of stratum corneum thickness and dermal capillary depth, the major involved variables.

  4. Differences in body circumferences, skin-fold thicknesses and lipid profiles among HIV-infected African children on and not on stavudine

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    V Musiime

    2012-11-01

    Full Text Available Purpose of the study To compare body circumferences, skin-fold thickness (SFT and lipid levels (LL, as measures of lipodystrophy, among antiretroviral therapy (ART-naïve and experienced children at enrolment into the CHAPAS-3 trial. Methods HIV-infected children in Uganda and Zambia, either ART-naïve or on stavudine (d4T for ≥2 years without clinical lipodystrophy, were randomised to receive d4T, abacavir (ABC or zidovudine (ZDV with lamivudine and efavirenz (EFV or nevirapine. At enrolment, mid-upper arm (MUAC and calf (CC circumferences, SFT (biceps, triceps, sub-scapular, supra-iliac and fasting lipids (total cholesterol (TC, low density lipo-protein (LDL, high density lipoprotein (HDL, triglycerides (TRIG were measured. Age/sex adjusted z-scores of MUAC, CC, SFT and the sum of SFT (SSF used Dutch reference data. ART-naïve and ART-experienced children were compared with t-tests using Stata v11.0. Summary of results Among 444 children, 224 (51% were male and 331 (74.5% ART-naïve. Mean (sd CD4% was 19.7% (10.2 versus (vs 34.2% (7.7 in ART-naïve vs ART-experienced children. The ART-naïve were younger than the ART-experienced children (median [IQR] age 2.5 [1.5, 4.0] vs 6.0 [5.5, 7.0] years, p<0.0001. Among the ART-experienced, 4/108 (3.7% were on EFV and median (IQR d4T use was 3.5 (2.7, 4.2 years. As expected, MUAC, CC, weight-for-age (WAZ and height-for-age (HAZ z-scores were lower in the ART-naïve; the ART-experienced had lower SFT z-scores and higher TC and HDL, but lower TRIG (Table 1. Conclusions Failure-to-thrive likely contributed to lower circumference values in ART-naïve children. Among the ART-experienced, thinner SFT and higher TC values could be ART (particularly d4T-related. Normal values, currently unavailable for African children, are being collected. During trial follow-up, we will evaluate the effect of ABC, ZDV and d4T on development of lipodystrophy in naïve children and its reversibility in d4T-treated children

  5. Body fat of rats of different age groups and nutritional states: assessment by micro-CT and skinfold thickness.

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    Tekus, Eva; Miko, Alexandra; Furedi, Nora; Rostas, Ildiko; Tenk, Judit; Kiss, Tamas; Szitter, Istvan; Balasko, Marta; Helyes, Zsuzsanna; Wilhelm, Marta; Petervari, Erika

    2018-02-01

    Obesity presents a growing public health problem. Therefore the analysis of body composition is important in clinical practice as well as in animal research models of obesity; hence precise methods for the assessment of body fat would be essential. We aimed to evaluate in vivo abdominal microcomputed tomography scan restricted to the L1-L3 region [micro-CT(L1-L3)], a skinfold thickness-based method (STM), and postmortem body composition analysis (PMA) with regard to whole body micro-CT scan in rats. Male Wistar rats of different age groups (from 3 to 24 mo) and nutritional states (normally fed, high-fat diet-induced obese, and calorie-restricted) were used. The fat percentage was determined with micro-CT(L1-L3) and whole body scan in anesthetized rats. Their skinfold thickness was measured in five locations with a Lange caliper. Wet weights of epididymal and retroperitoneal fat pads were determined via PMA. With regard to fat mass, the strongest correlation was observed between abdominal and whole body micro-CT. The other methods showed weaker associations with whole body micro-CT and with each other. Micro-CT(L1-L3) and PMA showed similar age-associated increase in fat mass between 3 and 18 mo. Micro-CT(L1-L3), STM, and PMA were efficient to detect differences in fat mass values in groups of different nutritional states. Micro-CT(L1-L3) appears to be a useful method for body fat assessment in rats with reduced scanning time. In rats, STM may also be a useful, low priced, noninvasive, and simple in vivo technique to assess obesity. NEW & NOTEWORTHY Body fat of rats assessed by in vivo abdominal microcomputed tomography of the L1-L3 region strongly correlates with values determined by whole body scan. Therefore, it is a useful method for fat assessment with reduced scanning time. Skinfold thickness measurement is an in vivo technique to assess progression of obesity in rats.

  6. Impact of the use of different skinfold calipers for the analysis of the body composition

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    Cyrino Edilson Serpeloni

    2003-01-01

    Full Text Available With the advances in the studies of body composition, it has been observed that several factors can interfere with the estimates of relative body fat using the skinfold thicknesses method. Therefore, the purpose of this study was to investigate the impact of the use of different skinfold calipers for the analysis of body composition by skinfold thicknesses measurements. Two hundred and fifty nine male subjects (23.3 ± 2.9 years took part of the study. Nine skinfold thicknesses were measured (abdominal, subscapular, suprailiac, triceps, biceps, midaxillary, chest, medial calf, and thigh using the Lange (USA and the Cescorf (Brazil calipers with accuracy of 1.0 and 0.1 mm, respectively. Significant differences were found in the comparison between the two calipers on all the investigated skinfold thicknesses (1.8 to 31.0% with highest values obtained by the Lange caliper (p < 0.01. When these values were applied to four different predictive equations, developed by different researchers, the body fat estimate was significantly modified (p < 0.01, resulting in differences of 5.2 to 6.9%. Results indicate that the use of different skinfold calipers may maximize the errors of estimation produced by different predictive equations used for the analysis of body composition.

  7. Percent body fat, skinfold thickness or body mass index for defining obesity or overweight, as a risk factor for asthma in schoolchildren: which one to use in epidemiological studies?

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    Garcia-Marcos, Luis; Valverde-Molina, Jose; Ortega, Maria L Castaños; Sanchez-Solis, Manuel; Martinez-Torres, Antonia E; Castro-Rodríguez, Jose A

    2008-10-01

    None of the epidemiological studies indicating that obesity is a risk factor for asthma in schoolchildren have used the percent body fat (PBF) to define obesity. The present study compares the definition of obesity using body mass index (BMI), PBF and the raw sum of the thickness of four skinfolds (SFT) to evaluate this condition as a risk factor for asthma. All classes of children of the target ages of 6-8 years of all schools in four municipalities of Murcia (Spain) were surveyed. Participation rate was 70.2% and the number of children included in the study was 931. Height, weight and SFT (biceps, triceps, subscapular and suprailiac) were measured according to standard procedures. Current active asthma was defined from several questions of the International Study of Asthma and Allergies in Childhood questionnaire. Obesity was defined using two standard cut-off points for BMI and PBF, and the 85th percentile for BMI, PBF and SFT. The highest quartile of each type of measurement was also compared with the lowest. A multiple logistic regression analysis was made for the various obesity definitions, adjusting for age, asthma in the mother and father and gender. The adjusted odds ratios of having asthma among obese children were different for boys and girls and varied across the different obesity definitions. For the standard cut-off points of BMI they were 1.19 [95% confidence interval (CI) 0.41-3.43] for girls and 2.00 (95% CI 0.97-4.10) for boys; however, for PBF (boys 25%, girls 30%) the corresponding figures were 1.54 (95% CI 0.63-3.73) and 1.20 (95% CI 0.66-2.21). BMI, PBF and SFT showed more consistency between each other when using the other cut-off points. BMI, PBF (except standard cut-off points) and SFT produce relatively comparable results when analysing the interaction between obesity and asthma.

  8. Changes in skinfold thickness and waist circumference after 12 and 24 months resulting from the NHF-NRG In Balance-project

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    Visscher Tommy LS

    2010-04-01

    Full Text Available Abstract Background More knowledge is needed regarding the effectiveness of weight gain prevention programmes. The present study tested the 12-and 24-month effectiveness of the 'Netherlands Research programme weight Gain prevention' (NHF-NRG-In Balance-project, a worksite-based intervention aimed at the prevention of weight gain. Methods Twelve worksites (n = 553 participants were matched and assigned to either intervention or control group. The worksites and employees of the intervention group received individual (i.e. pedometer, computer-tailored advice and environmental (i.e. changes in worksite canteen interventions, directed at physical activity and food intake over 1-year. Differences between the intervention and control group in changes in body weight, BMI, skinfold thickness and waist circumference at 12 and 24 months were examined using multilevel linear regression analyses adjusting for various baseline characteristics (age, gender, BMI, marital status, education and smoking status. Results A significant greater reduction in skinfold thickness was found in the intervention group than in the control group, both after 12-and 24 months (Unstandardized regression coefficients (B = -2.52, 95% C.I. -4.58, -0.45; p = 0.018; B = -4.83, 95% C.I. 6.98, -2.67; p Conclusions The project was effective with regard to changes in skinfold thickness and waist circumference both at 12 and 24 months. It supports the usefulness of worksite-based prevention, especially regarding maintenance of behavioral changes.

  9. Ecogeographical associations between climate and human body composition: analyses based on anthropometry and skinfolds.

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    Wells, Jonathan C K

    2012-02-01

    In the 19th century, two "ecogeographical rules" were proposed hypothesizing associations of climate with mammalian body size and proportions. Data on human body weight and relative leg length support these rules; however, it is unknown whether such associations are attributable to lean tissue (the heat-producing component) or fat (energy stores). Data on weight, height, and two skinfold thickness were obtained from the literature for 137 nonindustrialized populations, providing 145 male and 115 female individual samples. A variety of indices of adiposity and lean mass were analyzed. Preliminary analyses indicated secular increases in skinfolds in men but not women, and associations of age and height with lean mass in both sexes. Decreasing annual temperature was associated with increasing body mass index (BMI), and increasing triceps but not subscapular skinfold. After adjusting for skinfolds, decreasing temperature remained associated with increasing BMI. These results indicate that colder environments favor both greater peripheral energy stores, and greater lean mass. Contrasting results for triceps and subscapular skinfolds might be due to adaptive strategies either constraining central adiposity in cold environments to reduce cardiovascular risk, or favoring central adiposity in warmer environments to maintain energetic support of the immune system. Polynesian populations were analyzed separately and contradicted all of the climate trends, indicating support for the hypothesis that they are cold-adapted despite occupying a tropical region. It is unclear whether such associations emerge through natural selection or through trans-generational and life-course plasticity. These findings nevertheless aid understanding of the wide variability in human physique and adiposity. Copyright © 2011 Wiley Periodicals, Inc.

  10. Dual-energy X-ray absorptiometry, skinfold thickness and waist circumference for assessing body composition in ambulant and non-ambulant wheelchair games players

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    Annika eWillems

    2015-11-01

    Full Text Available Field-based assessments provide a cost–effective and accessible alternative to dual-energy X-ray absorptiometry (DXA for practitioners determining body composition in athletic populations. It remains unclear how the range of physical impairments classifiable in wheelchair sports may affect the utility of field-based body composition techniques. The present study assessed body composition using DXA in 14 wheelchair games players who were either wheelchair dependent (non-walkers; n =7 or relied on a wheelchair for sports participation only (walkers; n =7. Anthropometric measurements were used to predict body fat percentage with existing regression equations established for able-bodied persons by Sloan & Weir, Durnin & Womersley, Lean et al, Gallagher et al and Pongchaiyakul et al. In addition, linear regression analysis was performed to calculate the association between body fat percentage and BMI, waist circumference, sum of 6 skinfold thicknesses and sum of 8 skinfold thicknesses. Results showed that non-walkers had significantly lower total lean tissue mass (46.2±=6.6 kg vs. 59.4±8.2 kg, P =.006 and total body mass (65.8 ±4.2 kg vs. 79.4 ±14.9 kg; P =0.05 than walkers. Body fat percentage calculated from most existing regression equations was significantly lower than that from DXA, by 2 to 9% in walkers and 8 to14% in non-walkers. Of the anthropometric measurements, the sum of 8 skinfold thicknesses had the lowest standard error of estimation in predicting body fat content. In conclusion, existing anthropometric equations developed in able-bodied populations substantially underestimated body fat content in wheelchair athletes, particularly non-walkers. Impairment specific equations may be needed in wheelchair athletes.

  11. Body-composition measurement in 9-11-y-old children by dual-energy X-ray absorptiometry, skinfold-thickness measurements, and bioimpedance analysis.

    Science.gov (United States)

    Gutin, B; Litaker, M; Islam, S; Manos, T; Smith, C; Treiber, F

    1996-03-01

    We compared, in 9-11-y-old children (n=43), three measures of body composition: dual-energy X-ray absorptiometry (DXA), skinfold thickness, and bioimpedance analysis (BIA). The intraclass correlation coefficient (ICC), Bland-Altman procedure, and Spearman rank correlation were used to determine test-retest reliabilities of the three methods and to compare methods. For DXA measurements, the rank correlation between fat-free soft tissue and fat-free mass (FFM) was > 0.99, indicating that bone mineral content did not provide independent information. Thus, subsequent analyses used the two-compartment model (ie, fat mass and FFM) for all three techniques, focusing especially on values for percentage of fat. The test-retest reliabilities for all methods were high (ICCs > 0.994 and no significant differences between trials 1 and 2). The range of individual differences from trial 1 to trial 2 and Bland-Altman limits of agreement suggested that the reliability was greatest for DXA, followed by BIA and skinfold-thickness measurement. The percentage of fat values for the three methods were highly intercorrelated (all Spearman r values > 0.83). However, there was a systematic tendency (P < 0.01) for DXA values (mean: 23.98) to be higher than those derived from skinfold-thickness measurements (mean: 21.05) and BIA (mean: 21.52). The variance in percentage of fat values for BIA was significantly smaller than that for the other two techniques. These findings, along with rather large limits of agreement derived from the Bland-Altman procedure, suggest that the methods should not be used interchangeably.

  12. Secular trends for skinfolds differ from those for BMI and waist circumference among adults examined in NHANES from 1988-1994 through 2009-2010.

    Science.gov (United States)

    Freedman, David S; Zemel, Babette S; Ogden, Cynthia L

    2017-01-01

    Although the prevalence of a body mass index [BMI (in kg/m(2))] ≥30 has tripled among US adults since the 1960s, BMI is only moderately correlated with body fatness. Because skinfolds can more accurately estimate body fatness than can BMI, it is possible that skinfolds could be useful in monitoring secular trends in body fatness. We examined whether there were similar secular trends for skinfolds (triceps and subscapular), BMI, and waist circumference between US adults. This study was an analysis of 45,754 adults who participated in the NHANES from 1988-1994 through 2009-2010. Approximately 19% of the subjects were missing ≥1 skinfold-thickness measurement. These missing values were imputed from other characteristics. Trends in mean levels and in the prevalence of high levels of the 4 body size measures were fairly similar between men, with mean levels increasing by ≥5% from 1988-1994 through 2009-2010. Slightly larger increases were seen in women for BMI and waist circumference (7-8%), but trends in skinfolds were markedly different. The mean triceps skinfold, for example, increased by 2 mm through 2003-2004, but subsequently decreased so that the mean in 2009-2010 did not differ from that in 1988-1994. Compared with obese women in 1988-1994, the mean BMI of obese women in 2009-2010 was 1 higher, but mean levels of both skinfolds were 5-10% lower. Although there were fairly similar trends in levels of BMI, waist circumference, and skinfold thicknesses in men in the United States from 1988-1994 through 2009-2010, there were substantial differences in women. Our results indicate that it is unlikely that skinfold thicknesses could be used to monitor trends in obesity. © 2017 American Society for Nutrition.

  13. Body fat measurements in elite adolescent volleyball players: correlation between skinfold thickness, bioelectrical impedance analysis, air-displacement plethysmography, and body mass index percentiles.

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    Portal, Shawn; Rabinowitz, Jonathan; Adler-Portal, Dana; Burstein, Ruty Pilz; Lahav, Yair; Meckel, Yoav; Nemet, Dan; Eliakim, Alon

    2010-04-01

    Determination of body composition is an essential parameter in training athletes because low fat-muscle ratio might improve physical performance in many types of sports. Since training is often conducted in the field, it is important to determine whether simple field measurements of body composition assessment correlate with laboratory measurements. Examine the correlation of body fat content as measured using skinfold thicknesses (SF), air-displacement plethysmography (BOD POD), bioelectrical impedance analysis (BIA) and body mass index (BMI) age and gender adjusted percentiles. Body mass as measured by SF, BOD POD, BIA, and BMI percentiles were examined in 29 elite, national team level, male and female volleyball players (age range 13 to 18) at the beginning of the training season. Body fat percent measured by SF, BIA and BOD POD were highly positively correlated (r > 0.83). Measurements of body fat by SF, BIA and BOD POD were weakly correlated with BMI percentiles (r BOD POD are essentially interchangeable.

  14. Is the body adiposity index (hip circumference/height(1.5)) more strongly related to skinfold thicknesses and risk factor levels than is BMI? The Bogalusa Heart Study.

    Science.gov (United States)

    Freedman, David S; Blanck, Heidi M; Dietz, William H; DasMahapatra, Pronabesh; Srinivasan, Sathanur R; Berenson, Gerald S

    2013-01-28

    Because of its strong association (r 0.85) with percentage of body fat determined by dual-energy X-ray absorptiometry, hip circumference divided by height(1.5) (the body adiposity index) has recently been proposed as an index of body fatness among adults. We examined whether this proposed index was more strongly associated with skinfold thicknesses and levels of CVD risk factors (lipids, fasting insulin and glucose, and blood pressure) than was BMI among 2369 18- to 49-year-olds in the Bogalusa Heart Study. All analyses indicated that the body adiposity index was less strongly associated with skinfold thicknesses and CVD risk factors than was either waist circumference or BMI. Correlations with the skinfold sum, for example, were r 0.81 (BMI) v. r 0.75 (body adiposity index) among men, and r 0.87 (BMI) v. r 0.80 among women; PBMI (r 0.58) and waist circumference (r 0.61) than with the body adiposity index (r 0.49). The weaker associations with the body adiposity index were observed in analyses stratified by sex, race, age and year of examination. Multivariable analyses indicated that if either BMI or waist circumference were known, the body adiposity index provided no additional information on skinfold thicknesses or risk factor levels. These findings indicate that the body adiposity index is likely to be an inferior index of adiposity than is either BMI or waist circumference.

  15. Is the body adiposity index (hip circumference/height1·5) more strongly related to skinfold thicknesses and risk factor levels than is BMI? The Bogalusa Heart Study

    Science.gov (United States)

    Freedman, David S.; Blanck, Heidi M.; Dietz, William H.; DasMahapatra, Pronabesh; Srinivasan, Sathanur R.; Berenson, Gerald S.

    2015-01-01

    Because of its strong association (r 0·85) with percentage of body fat determined by dual-energy X-ray absorptiometry, hip circumference divided by height1·5 (the body adiposity index) has recently been proposed as an index of body fatness among adults. We examined whether this proposed index was more strongly associated with skinfold thicknesses and levels of CVD risk factors (lipids, fasting insulin and glucose, and blood pressure) than was BMI among 2369 18- to 49-year-olds in the Bogalusa Heart Study. All analyses indicated that the body adiposity index was less strongly associated with skinfold thicknesses and CVD risk factors than was either waist circumference or BMI. Correlations with the skinfold sum, for example, were r 0·81 (BMI) v. r 0·75 (body adiposity index) among men, and r 0·87 (BMI) v. r 0·80 among women; PBMI (r 0·58) and waist circumference (r 0·61) than with the body adiposity index (r 0·49). The weaker associations with the body adiposity index were observed in analyses stratified by sex, race, age and year of examination. Multivariable analyses indicated that if either BMI or waist circumference were known, the body adiposity index provided no additional information on skinfold thicknesses or risk factor levels. These findings indicate that the body adiposity index is likely to be an inferior index of adiposity than is either BMI or waist circumference. PMID:22716994

  16. Comparison of Skinfold Thicknesses and Bioimpedance Spectroscopy to Dual-Energy X-Ray Absorptiometry for the Body Fat Measurement in Patients With Chronic Kidney Disease.

    Science.gov (United States)

    Rymarz, Aleksandra; Szamotulska, Katarzyna; Niemczyk, Stanisław

    2017-08-01

    The aim of the study was to compare the amount of body fat measured by skinfold thickness (SFT) and bioimpedance spectroscopy (BIS) with dual-energy x-ray absorptiometry (DXA) as a reference method. Forty-eight patients undergoing hemodialysis treatment thrice-weekly for at least 3 months (HD group) with a mean age of 59.8 ± 15.5 years, 61 patients with chronic kidney disease (CKD) with an estimated glomerular filtration rate (eGFR) 60 mL/min/1.73 m2 and a mean age of 58.7 ± 17.0 years (control group) were included. Mean percentages of body fat measured by SFT did not significantly differ from those measured by DXA in the HD group ( P = .249) and the PreD group ( P = .355). In the control group, mean percentage of fat mass measured by SFT was significantly higher than measured by DXA ( P = .004). Mean difference was 1.99% ± 3.65%. The measurements of body fat performed by BIS were significantly higher than those performed by DXA in all studied groups ( P measurements obtained by BIS and DXA in all studied groups ( R2 = 0.302, 0.153, and 0.250, respectively, for HD, PreD, and control groups). SFT as a method of fat mass assessment in daily routine practice seems to be more reliable then BIS in patients treated with hemodialysis and in patients with stage IV/V CKD. However, methods based on bioimpedance techniques can potentially offer more data such as overhydration or an amount of lean tissue mass, but further investigations are needed to establish method the most suitable for patients with CKD.

  17. Is the body adiposity index (hip circumference/height1·5) more strongly related to skinfold thicknesses and risk factor levels than is BMI? The Bogalusa Heart Study

    OpenAIRE

    David S. Freedman; Blanck, Heidi M.; Dietz, William H.; DasMahapatra, Pronabesh; Srinivasan, Sathanur R.; Berenson, Gerald S

    2012-01-01

    Because of its strong association (r 0·85) with percentage of body fat determined by dual-energy X-ray absorptiometry, hip circumference divided by height1·5 (the body adiposity index) has recently been proposed as an index of body fatness among adults. We examined whether this proposed index was more strongly associated with skinfold thicknesses and levels of CVD risk factors (lipids, fasting insulin and glucose, and blood pressure) than was BMI among 2369 18- to 49-year-olds in the Bogalusa...

  18. Exercise induced dehydration status and skinfold compressibility in athletes: an intervention study.

    Science.gov (United States)

    Araújo, Daniela; Teixeira, Vitor Hugo; Carvalho, Pedro; Amaral, Teresa F

    2018-01-01

    Skinfold thickness assessment is a widely recognized technique for the estimation of body adiposity and fat free mass. This method assumes that skinfolds' compressibility is constant but there are some factors that could influence its compressibility. This study aims to evaluate whether the skinfolds' compressibility is influenced by hydration status. An intervention study was conducted in a sample of 22 adult male amateur soccer players, who took part in a 90min simulated soccer match. Before and after the intervention skinfolds thicknesses were measured in eight anatomical sites. An electronic caliper, Lipotool, was used to collect and record 120 values during 2s of evaluation. To analyze skinfolds' compressibility, two methods were used: identification of lowest skinfold thickness measurement (SL) and SH = 110% x SL, and the parameter TAU (τ) determination. Baseline hydration status was evaluated by total body water (TBW) through multifrequency bioimpedance analysis. Dehydration was assessed by the difference of body weight before and after the intervention. The intervention resulted in a loss of 2.11% of participants' baseline weight. The skinfolds thicknesses, assessed by SL and SH, were significantly higher after exercise for all skinfolds except for skinfolds at iliac crest and abdominal. This intervention did not affect skinfolds' compressibility when assessed by τ. However, an association between dehydration and medial-calf skinfold' compressibility was found (r=0.48, p=0.042). Although an increase in the skinfolds thickness after the intervention was found, skinfolds' compressibility did not change.

  19. RELATIVE TOTAL BODY FAT AND SKINFOLD PATTERNING IN FILIPINO NATIONAL COMBAT SPORT ATHLETES

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    Luigi T. Bercades

    2006-07-01

    Full Text Available The purpose of this study was to assess relative total body fat and skinfold patterning in Filipino national karate and pencak silat athletes. Participants were members of the Philippine men's and women's national teams in karate (12 males, 5 females and pencak silat (17 males and 5 females. In addition to age, the following anthropometric measurements were taken: height, body mass, triceps, subscapular, supraspinale, umbilical, anterior thigh and medial calf skinfolds. Relative total body fat was expressed as sum of six skinfolds. Sum of skinfolds and each individual skinfold were also expressed relative to Phantom height. A two-way (Sport*Gender ANOVA was used to determine the differences between men and women in total body fat and skinfold patterning. A Bonferroni-adjusted alpha was employed for all analyses. The women had a higher proportional sum of skinfols (80.19 ± 25.31 mm vs. 51.77 ± 21.13 mm, p = 0. 001, eta2 = 0.275. The men had a lower proportional triceps skinfolds (-1.72 ± 0.71 versus - 0.35 ± 0.75, p < 0.001. Collapsed over gender, the karate athletes (-2.18 ± 0.66 had a lower proportional anterior thigh skinfold than their pencak silat colleagues (-1.71 ± 0.74, p = 0.001. Differences in competition requirements between sports may account for some of the disparity in anthropometric measurements

  20. Utilização da espessura de dobras cutâneas para a estimativa da gordura corporal em idosos Estimating body fat from skinfold thicknesses in the elderly

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    Cassiano Ricardo Rech

    2010-02-01

    Full Text Available OBJETIVO: Analisar a concordância de equações de espessura de dobras cutâneas para a estimativa da gordura corporal em idosos brasileiros, tendo como referência a Absortometria Radiológica de Dupla Energia. MÉTODOS: Trata-se de um estudo correlacional. Realizaram-se as medidas antropométricas (estatura, massa corporal, perímetros corporais e espessura de dobras cutâneas de 180 idosos (60 homens e 120 mulheres com idades entre 60 e 81 anos. A gordura corporal foi mensurada por meio da Absormetria Radiológica de Dupla Energia e comparada com os valores estimados pelas dobras cutâneas. Foram analisadas as equações de Durnin et al., Jackson etal., Visser et al. e Lean et al. Os critérios de validação cruzada sugeridos por Lohman e a análise gráfica das dispersões em relação à média, por meio do método proposto por Bland & Altman, foram utilizados. RESULTADOS: O grupo avaliado apresentou uma gordura corporal média de 23,1% (DP=5,8% nos homens e 37,3% (DP=6,9% nas mulheres, com uma variação entre 6% a 51,4%. Houve uma elevada concordância entre as equações generalizadas de Durnin et al. e a Absormetria Radiológica de Dupla Energia (64,4% nos homens e 60,1% nas mulheres. Nos homens as equações de dobras cutâneas tenderam a superestimar os valores de gordura corporal, já nas mulheres esses valores foram subestimados. CONCLUSÃO: As equações generalizadas desenvolvidas por Durnin et al. são válidas para a estimativa da gordura corporal em idosos do sul do Brasil.OBJECTIVE: The objective of this study was to analyze skinfold thickness equations for the estimation of body fat in terms of their concordance with dual energy X-ray absorptiometry results in elderly Brazilians. METHODS: This was a correlation study. Anthropometric measurements (height, body mass, body circumferences and skin fold thicknesses of 180 elderly subjects (60 men and 120 women aged 60 to 81 years were taken. Their body fat was measured with dual

  1. Estimativa da gordura corporal através de equipamentos de bioimpedância, dobras cutâneas e pesagem hidrostática Comparison of body fat estimation by bioelectric impedance, skinfold thickness, and underwater weighing

    Directory of Open Access Journals (Sweden)

    Maurício Nunes Rodrigues

    2001-08-01

    Full Text Available A estimativa do percentual de gordura (%G pela bioimpedância (BIA tem como vantagem a simplicidade da medida. Contudo, a confiabilidade da BIA tem sofrido críticas. O objetivo deste estudo foi comparar a estimativa do %G através das técnicas de bioimpedância (RJL-101; Byodinamics A-310, Maltron BF-900 e BF-906, de dobras cutâneas (DC e da pesagem hidrostática (PH. Observaram-se 25 indivíduos, homogeneizados segundo raça (branca, gênero (masculino e idade (18 a 36 anos. Para a medida de BIA foi utilizada a padronização proposta por Lukaski et al. (1985, 1986. Para as DC foram utilizadas as equações de å 3 DC e å 7 DC (Jackson, Pollock, 1978. Os valores de %G e de volume residual para PH foram preditos, respectivamente, pelas equações de Siri (1961 e Goldman e Becklake (1959. A análise estatística compreendeu: a comparação entre os métodos através da ANOVA com medidas repetidas seguida de testes post-hoc de Tukey; b correlação de Pearson (r; e c cálculo do erro padrão de estimativa (SEE das técnicas em relação à PH. Os resultados indicaram que: a as medidas de BIA não diferiram significativamente, entre si, para o %G estimado; b As medidas dos aparelhos A-310 e BF-906 não coincidiram com a PH (p The main advantage of the bioelectric impedance method (BIA in the determination of body fat (%BF is the simplicity of the procedure. However, its accuracy and reliability have been criticized. The purpose of this study was to compare the %BF obtained by BIA (RJL-101; Biodynamics A-310, Maltron BF-900 e BF-906, by skinfold thickness (ST, and by underwater weighing (UW. Twenty-five subjects, divided in homogenous groups according to age (18 to 36 years, sex (men, and race (white participated in the study. BIA measures were taken using the Lukaski et al. standardization (1985,1986. ST was taken by using the equation of 3 and 7 skinfolds (Jackson, Pollock, 1978. The values of %BF and residual volume for the UW were estimated

  2. Racial differences in the sums of skinfolds and percentage of body fat estimated from impedance in black and white girls, 9 to 19 years of age : The National Heart, Lung, and Blood Institute Growth and Health Study

    NARCIS (Netherlands)

    Morrison, JA; Barton, BA; Obarzanek, E; Crawford, PB; Guo, SS; Schreiber, GB

    Objectives: This National Heart, Lung, and Blood Institute Growth and Health Study report assesses racial differences in fat patterning in black and white girls ages 9 to 19 years, comparing the sum of triceps and subscapular skinfolds (SSFs) and percentage of body fat (%BF) from impedance as two

  3. Skinfold reference curves and their use in predicting metabolic syndrome risk in children.

    Science.gov (United States)

    Andaki, Alynne C R; Quadros, Teresa M B de; Gordia, Alex P; Mota, Jorge; Tinôco, Adelson L A; Mendes, Edmar L

    To draw skinfold (SF) reference curves (subscapular, suprailiac, biceps, triceps) and to determine SF cutoff points for predicting the risk of metabolic syndrome (MetS) in children aged 6-10 years old. This was a cross-sectional study with a random sample of 1480 children aged 6-10 years old, 52.2% females, from public and private schools located in the urban and rural areas of the municipality of Uberaba (MG). Anthropometry, blood pressure, and fasting blood samples were taken at school, following specific protocols. The LMS method was used to draw the reference curves and ROC curve analysis to determine the accuracy and cutoff points for the evaluated skinfolds. The four SF evaluated (subscapular, suprailiac, biceps, and triceps) and their sum (∑4SF) were accurate in predicting MetS for both girls and boys. Additionally, cutoffs have been proposed and percentile curves (p5, p10, p25, p50, p75, p90, and p95) were outlined for the four SF and ∑4SF, for both genders. SF measurements were accurate in predicting metabolic syndrome in children aged 6-10 years old. Age- and gender-specific smoothed percentiles curves of SF provide a reference for the detection of risk for MetS in children. Copyright © 2017. Published by Elsevier Editora Ltda.

  4. Percentage of body fat in adolescents with Down syndrome: Estimation from skinfolds.

    Science.gov (United States)

    González-Agüero, Alejandro; Matute-Llorente, Ángel; Gómez-Cabello, Alba; Vicente-Rodríguez, Germán; Casajús, José A

    2017-01-01

    Adolescents with Down syndrome (DS) have a unique morphology and body shape, and this needs to be taken into account when assessing body fat percentage (BF%). To develop a predictive equation from anthropometric variables (skinfolds) for estimating BF% in adolescents with DS. Twenty-three adolescents with DS (7 girls, 16 boys) participated in the study; seven skinfold measurements were taken (biceps, triceps, subscapular, supraspinale, abdominal, front thigh, and medial calf), circumferences and diameters were measured following ISAK recommendations. Total body volume (and then body density) was measured with air displacement plethysmography (ADP); BF% was then calculated. Correlation between anthropometry data and BF% by ADP, and stepwise regression analyses were applied to develop a specific prediction equation. All the skinfolds, BMI, hip, waist and thigh circumferences correlated with BF% and were included in the regression analysis; sex and triceps were added into the model (R2 = 0.89, p < 0.05). Therefore the proposed equation computed as follows: BF% = (0.97 TR) - (8.869·SEX) + 15.6 where TR is triceps skinfolds (mm) and SEX is equal to 0 for female and 1 for male. The proposed prediction equation is recommended for the assessment of BF% in adolescents with DS as it is the only one specifically developed and validated in this unique population. It is a cheap, reliable and accessible method that removes the need for use of expensive equipment. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Technique for Measuring Body Circumferences and Skinfold Thicknesses.

    Science.gov (United States)

    1984-08-01

    are now touching the second costo -sternal joint (Figure 3a). There is usually a slight bulge or prominence on the sternum at this level. This...Naval Medical Command, National Capital Region 13. NUMBER OFPAGES Bethesda, NO 20814 45 14. MONITORING AGENCY NAME & ADDRESS(If different bow Controling

  6. Posterior subscapular dissection: An improved approach to the brachial plexus for human anatomy students.

    Science.gov (United States)

    Hager, Shaun; Backus, Timothy Charles; Futterman, Bennett; Solounias, Nikos; Mihlbachler, Matthew C

    2014-05-01

    Students of human anatomy are required to understand the brachial plexus, from the proximal roots extending from spinal nerves C5 through T1, to the distal-most branches that innervate the shoulder and upper limb. However, in human cadaver dissection labs, students are often instructed to dissect the brachial plexus using an antero-axillary approach that incompletely exposes the brachial plexus. This approach readily exposes the distal segments of the brachial plexus but exposure of proximal and posterior segments require extensive dissection of neck and shoulder structures. Therefore, the proximal and posterior segments of the brachial plexus, including the roots, trunks, divisions, posterior cord and proximally branching peripheral nerves often remain unobserved during study of the cadaveric shoulder and brachial plexus. Here we introduce a subscapular approach that exposes the entire brachial plexus, with minimal amount of dissection or destruction of surrounding structures. Lateral retraction of the scapula reveals the entire length of the brachial plexus in the subscapular space, exposing the brachial plexus roots and other proximal segments. Combining the subscapular approach with the traditional antero-axillary approach allows students to observe the cadaveric brachial plexus in its entirety. Exposure of the brachial dissection in the subscapular space requires little time and is easily incorporated into a preexisting anatomy lab curriculum without scheduling additional time for dissection. Copyright © 2014 Elsevier GmbH. All rights reserved.

  7. Skinfolds and coronary heart disease risk factors are more strongly associated with BMI than with the body adiposity index.

    Science.gov (United States)

    Freedman, David S; Ogden, Cynthia L; Goodman, Alyson B; Blanck, Heidi M

    2013-01-01

    A recent, cross-sectional analysis of adults found that the hip circumference divided by height(1.5) minus 18 (the body adiposity index, BAI) was strongly correlated (r = 0.79) with percent body fat determined by dual energy X-ray absorptiometry. The BAI was proposed as a more accurate index of body fatness than BMI. We examined whether BAI was more strongly related, than was BMI and waist circumference, to skinfold thicknesses and levels of various risk factors for coronary heart disease. Cross-sectional analyses of adults (n = 14,263 for skinfold thickness; n=6291 for fasting lipid levels) in the National Health and Nutrition Examination Survey (NHANES) III, 1988-1994. As compared with BMI and waist circumference, we found that BAI was less strongly associated with the skinfold sum and with risk factor levels. For example, correlations with the skinfold sum were r = 0.79 (BMI) vs. r = 0.70 (BAI) among men, and r = 0.86 (BMI) vs. r = 0.79 (BAI) among women; p BMI and waist circumference than BAI in analyses stratified by sex, race-ethnicity and age. Multivariable analyses indicated that if BMI was known, BAI provided little additional information on risk factor levels. Based on the observed associations with risk factor levels and skinfold thicknesses, we conclude that BAI is unlikely to be a better index of adiposity than BMI. Copyright © 2012 The Obesity Society.

  8. Chimaeric subscapular system free flap for complex oro-facial defects.

    Science.gov (United States)

    L'Heureux-Lebeau, B; Odobescu, A; Harris, P G; Guertin, L; Danino, A M

    2013-07-01

    Ablation of locally advanced head and neck cancers generally results in large composite oro-facial defects. Due to the often-large segment of mandible missing, as well as the need to provide skin coverage and oral lining, reconstructive options are limited. We present our experience in oncologic head and neck reconstruction using chimaeric subscapular system free flaps. We performed a retrospective chart review of patients presenting important through-and-through oro-facial defects following ablation of T3, T4a or T4b tumours in two university centres between 2005 and 2011. All defects were reconstructed with a subscapular system free flap that was harvested in a dorsal decubitus position. Sixteen patients (15 M, 1 F; mean age=60 years) underwent mandibular reconstruction with latissimus dorsi flaps with one or two skin paddles and one bony component based on the angular branch of the thoracodorsal artery. Fifteen patients received adjuvant radiotherapy. We experienced no flap loss. Donor-site complications were minimal, albeit a limitation of shoulder range of motion was found in four patients. Eight patients presented postoperative complications requiring re-intervention. Fourteen patients were able to recommence oral nutrition and their diction returned to normal in all but one. The mean follow-up period was 25 months. Aesthetic results were satisfactory upon atrophy of the latissimus dorsi muscle. In cases of extensive oro-facial defects involving a large mandibular segment, reconstruction with subscapular system free-tissue transfer is a safe and reliable technique that offers satisfactory functional and aesthetic results. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  9. Neuronal genes for subcutaneous fat thickness in human and pig are identified by local genomic sequencing and combined SNP association study.

    Directory of Open Access Journals (Sweden)

    Kyung-Tai Lee

    Full Text Available Obesity represents a major global public health problem that increases the risk for cardiovascular or metabolic disease. The pigs represent an exceptional biomedical model related to energy metabolism and obesity in humans. To pinpoint causal genetic factors for a common form of obesity, we conducted local genomic de novo sequencing, 18.2 Mb, of a porcine QTL region affecting fatness traits, and carried out SNP association studies for backfat thickness and intramuscular fat content in pigs. In order to relate the association studies in pigs to human obesity, we performed a targeted genome wide association study for subcutaneous fat thickness in a cohort population of 8,842 Korean individuals. These combined association studies in human and pig revealed a significant SNP located in a gene family with sequence similarity 73, member A (FAM73A associated with subscapular skin-fold thickness in humans (rs4121165, GC-corrected p-value  = 0.0000175 and with backfat thickness in pigs (ASGA0029495, p-value  = 0.000031. Our combined association studies also suggest that eight neuronal genes are responsible for subcutaneous fat thickness: NEGR1, SLC44A5, PDE4B, LPHN2, ELTD1, ST6GALNAC3, ST6GALNAC5, and TTLL7. These results provide strong support for a major involvement of the CNS in the genetic predisposition to a common form of obesity.

  10. Quantitation of the lower subscapular nerve for potential use in neurotization procedures.

    Science.gov (United States)

    Tubbs, R Shane; Khoury, Charles A; Salter, E George; Acakpo-Satchivi, Leslie; Wellons, John C; Blount, Jeffrey P; Oakes, W Jerry

    2006-12-01

    New information regarding nerve branches of the brachial plexus can be useful to the surgeon performing neurotization procedures following patient injury. Nerves in the vicinity of the axillae have been commonly used for neural grafting procedures, with the exception of the lower subscapular nerve (LSN). The authors dissected and measured the LSN in 47 upper extremities (left and right sides) obtained in 27 adult cadavers, and determined distances between the LSN and surrounding nerves to help quantify it for possible use in neurotization procedures. The mean diameter of the LSN was 2.3 mm. The mean length of the LSN from its origin at the posterior cord until it branched to the subscapularis muscle was 3.5 cm, and the mean distance from this branch until its termination in the teres major muscle was 6 cm. Therefore, the mean length of the entire LSN from the posterior cord to the teres major was 9.5 cm. When the LSN was mobilized to explore its possible use in neurotization, it reached the entrance site of the musculocutaneous nerve into the coracobrachialis muscle in all but three sides and was within 1.5 cm from this point in these three. In the other specimens, the mean length of the LSN distal to this site of the musculocutaneous nerve was 2 cm. The mobilized LSN reached the axillary nerve trunk as it entered the quadrangular space in all specimens. The mean length of the LSN distal to this point on the axillary nerve was 2.5 cm. Furthermore, on all but one side the LSN was found within the confines of an anatomical triangle previously described by the authors. The authors hope that these data will prove useful to the surgeon for both identifying the LSN and planning for potential neurotization procedures of the brachial plexus.

  11. 2017-11-20T18:08:29Z https://www.ajol.info/index.php/all/oai oai:ojs ...

    African Journals Online (AJOL)

    Various parameters have been measured to give some estimates about the ... to know the best index for the measurement of obesity among patients with type 2 ... well with waist circumference (WC) and subscapular skinfold thickness (SST) ...

  12. Validation of a New Skinfold Prediction Equation Based on Dual-Energy X-Ray Absorptiometry

    Science.gov (United States)

    Ball, Stephen; Cowan, Celsi; Thyfault, John; LaFontaine, Tom

    2014-01-01

    Skinfold prediction equations recommended by the American College of Sports Medicine underestimate body fat percentage. The purpose of this research was to validate an alternative equation for men created from dual energy x-ray absorptiometry. Two hundred ninety-seven males, aged 18-65, completed a skinfold assessment and dual energy x-ray…

  13. Treatment of internal rotation contracture of the shoulder in obstetric brachial plexus lesions by subscapular tendon lengthening and open reduction: early results and complications

    NARCIS (Netherlands)

    van der Sluijs, Johannes A.; van Ouwerkerk, Willem J. R.; de Gast, Arthur; Nollet, Frans; Winters, Hay; Wuisman, Paul I. J. M.

    2004-01-01

    In this prospective study of 19 consecutive children, the operative treatment of internal rotation contracture of the shoulder in obstetric brachial plexus lesions by subscapular tendon lengthening and open reduction of the humeral head is evaluated. The average age of the children was 3.7 years and

  14. Adiposity measurements by BMI, skinfolds and dual energy X-ray absorptiometry in relation to risk markers for cardiovascular disease and diabetes in adult males.

    Science.gov (United States)

    Hariri, Ahmad A; Oliver, Nicholas S; Johnston, Desmond G; Stevenson, John C; Godsland, Ian F

    2013-01-01

    Choice of adiposity measure may be important in the evaluation of relationships between adiposity and risk markers for cardiovascular disease and diabetes. We explored the strengths of risk marker associations with BMI, a simple measure of adiposity, and with measures provided by skinfold thicknesses and dual energy X-ray absorptiometry (DXA). We evaluated in three subgroups of white males (n = 156-349), participating in a health screening program, the strengths of relationship between measures of total and regional adiposity and risk markers relating to blood pressure, lipids and lipoproteins, insulin sensitivity, and subclinical inflammation. Independent of age, smoking, alcohol intake, and exercise, the strongest correlations with adiposity measures were seen with serum triglyceride concentrations and indices of insulin sensitivity, with strengths of association showing little difference between BMI and skinfold and DXA measures of total and percent body fat (R = 0.20-0.46, P adiposity were seen for serum HDL cholesterol and only relatively inconsistent associations with adiposity for total and LDL cholesterol and indices of subclinical inflammation. BMI can account for variation in risk markers in white males as well as more sophisticated measures derived from skinfold thickness measurements or DXA scanning.

  15. Developing best practices teaching procedures for skinfold assessment: observational examination using the Think Aloud method.

    Science.gov (United States)

    Holmstrup, Michael E; Verba, Steven D; Lynn, Jeffrey S

    2015-12-01

    Skinfold assessment is valid and economical; however, it has a steep learning curve, and many programs only include one exposure to the technique. Increasing the number of exposures to skinfold assessment within an undergraduate curriculum would likely increase skill proficiency. The present study combined observational and Think Aloud methodologies to quantify procedural and cognitive characteristics of skinfold assessment. It was hypothesized that 1) increased curricular exposure to skinfold assessment would improve proficiency and 2) the combination of an observational and Think Aloud analysis would provide quantifiable areas of emphasis for instructing skinfold assessment. Seventy-five undergraduates with varied curricular exposure performed a seven-site skinfold assessment on a test subject while expressing their thoughts aloud. A trained practitioner recorded procedural observations, with transcripts generated from audio recordings to capture cognitive information. Skinfold measurements were compared with a criterion value, and bias scores were generated. Participants whose total bias fell within ±3.5% of the criterion value were proficient, with the remainder nonproficient. An independent-samples t-test was used to compare procedural and cognitive observations across experience and proficiency groups. Additional curricular exposure improved performance of skinfold assessment in areas such as the measurement of specific sites (e.g., chest, abdomen, and thigh) and procedural (e.g., landmark identification) and cognitive skills (e.g., complete site explanation). Furthermore, the Think Aloud method is a valuable tool for determining curricular strengths and weaknesses with skinfold assessment and as a pedagogical tool for individual instruction and feedback in the classroom. Copyright © 2015 The American Physiological Society.

  16. A comparison between skinfold callipers and ultrasound imaging for ...

    African Journals Online (AJOL)

    The objective of this study was to compare measurements recorded by SC and USI for the assessment of subcutaneous fat thickness in order to estimate %BF. Thirty adults volunteered for the study. Body mass, stature and subcutaneous fat thickness for seven sites were measured. Strong (p<0.01) correlations were found ...

  17. Estimation of body fat: correlation between skinfold measurements and selected indices of adiposity.

    Science.gov (United States)

    Sanya, A O; Alaje, O T

    1998-01-01

    The purpose of this study was to find out which index of adiposity among three selected adiposity indices (weight-height, Quetelet and modified ponderal) will correlate best with each of sum of sex-specific skinfolds and percent body fat estimated from skinfold measurements. A total of one hundred and forty subjects participated in the study, they were distributed into three groups using age as distribution criterion. The age groups were Group A (16 years to 25 years), Group B (26 - 35 years) and Group C (36 - 45 years). From the weights and heights of the subjects, the values of the three indices of adiposity were computed while the sum of skinfolds and percent body fat were computed from skinfold measurements. The Pearson's product correlation revealed index and estimate of adiposity was weight-height index for males, and Quetelet index for female subjects between 16 and 25 years of age. Modified ponderal index correlated best for males and Quetelet index for females in group B, while Quetelet index correlated best for males and modified ponderal index for females in group C. The clinical application for these results is that a single adiposity index should not be employed for all subjects. The adiposity index used for the estimation of body fat should depend on the sex and age of the subject.

  18. Caucasian children's fat mass: routine anthropometry v. air-displacement plethysmography.

    Science.gov (United States)

    Michels, Nathalie; Huybrechts, Inge; Bammann, Karin; Lissner, Lauren; Moreno, Luis; Peeters, Maarten; Sioen, Isabelle; Vanaelst, Barbara; Vyncke, Krishna; De Henauw, Stefaan

    2013-04-28

    The present paper will use fat mass percentage (FM%) obtained via BOD POD® air-displacement plethysmography (FMADP%) to examine the relative validity of (1) anthropometric measurements/indices and (2) of FM% assessed with equations (FMeq%) based on skinfold thickness and bioelectrical impedance (BIA). In 480 Belgian children (aged 5-11 years) weight, height, skinfold thickness (triceps and subscapular), body circumferences (mid-upper arm, waist and hip), foot-to-foot BIA (Tanita®) and FMADP% were measured. Anthropometric measurements and calculated indices were compared with FMADP%. Next, published equations were used to calculate FMeq% using impedance (equations of Tanita®, Tyrrell, Shaefer and Deurenberg) or skinfold thickness (equations of Slaughter, Goran, Dezenberg and Deurenberg). Both indices and equations performed better in girls than in boys. For both sexes, the sum of skinfold thicknesses resulted in the highest correlation with FMADP%, followed by triceps skinfold, arm fat area and subscapular skinfold. In general, comparing FMeq% with FMADP% indicated mostly an age and sex effect, and an increasing underestimation but less dispersion with increasing FM%. The Tanita® impedance equation and the Deurenberg skinfold equation performed the best, although none of the used equations were interchangeable with FMADP%. In conclusion, the sum of triceps and subscapular skinfold thickness is recommended as marker of FM% in the absence of specialised technologies. Nevertheless, the higher workload, cost and survey management of an immobile device like the BOD POD® remains justified.

  19. High prevalence of malnutrition among patients with solid non-hematological tumors as found by using skinfold and circumference measurements

    Directory of Open Access Journals (Sweden)

    Adriana Garófolo

    Full Text Available CONTEXT AND OBJECTIVE: Malnutrition in cancer patients has many causes. Nutritional status is usually assessed from weight/height indices. These present limitations for the nutritional assessment of cancer patients: their weights include tumor mass, and lean mass changes are not reflected in weight/height indices. The objective was to evaluate differences between two anthropometric methods and compare deficits, in non-hematological tumor patients and hematological disease patients. DESIGN AND SETTING: Cross-sectional study at Instituto de Oncologia Pediátrica, Universidade Federal de São Paulo. METHODS: Children and adolescents were evaluated between March 1998 and January 2000. Traditional anthropometric measurements were obtained in the first month of treatment (induction therapy, by weight-for-height (W/H using z-scores index for children and body mass index (BMI for adolescents. Body composition evaluations consisted of specific anthropometric measurements: triceps skinfold thickness (TSFT, mid-upper arm circumference (MUAC and arm muscle circumference (AMC. Data were analyzed to compare nutritional assessment methods for diagnosing malnutrition prevalence. The chi-squared test was used for comparative analyses between tumor patients and hematological disease patients. RESULTS: Analysis was done on 127 patients with complete data. Higher percentages of deficits were found among tumor patients, by W/H z-scores or BMI and by MUAC and AMC. Higher percentages of deficits were shown by TSFT (40.2% and MUAC (35.4% than by W/H z-scores or BMI (18.9%. CONCLUSION: Non-hematological tumor patients presented higher malnutrition prevalence than did hematological disease patients. Body composition measurements by TSFT and MUAC detected more patients with malnutrition than did W/H or BMI.

  20. Interdisciplinary intervention on body composition and physical fitness tests in obese children

    Directory of Open Access Journals (Sweden)

    José Cazuza de Farias Junior

    2012-03-01

    Full Text Available Lifestyle changes are an important factor in the management and prevention of childhood obesity. The objective of this study was to analyze the effects of an exercise program (based on recreational activities and nutritional counseling on body composition and physical fitness test performance in obese children. Forty-four children aged 8 to 11 years were divided into two gender- and age-matched groups, intervention (n = 22 and control (n = 22. Several parameters were measured before and after 12 weeks of participation in the program: weight, height, skinfold thickness (biceps, triceps, subscapular, suprailiac, abdominal and medial calf, circumferences (abdominal, arm, hip and calf and the abdominal flexion and handgrip flexibility tests. The control group did not take part in the intervention. Thirty-two patients completed the study (16 in each group. The intervention group showed significant reductions in body mass index, triceps, subscapular and abdominal skinfold thickness, arm girth and sum of trunk skinfolds. There was a significant increase in right grip strength and abdominal strength. The control group showed a significant increase in body mass, waist circumference, subscapular and calf skinfold thickness, sum of trunk skinfolds, sum of limb skinfolds and arm and calf perimeters, as well as reduction in right hand grip strength. We conclude that the program was effective in reducing body fat and increasing physical fitness in children.

  1. Sex Differences In Anthropometric Characteristics Of Nigerian ...

    African Journals Online (AJOL)

    The aim of this study was to assess the anthropometric and body composition profiles of Nigerian school children. A cross-sectional study was carried out involving 1036 girls and 979 boys aged 9-12 years. Anthropometric measurements, including body mass, stature, triceps, subscapular and medial calf skinfold thickness, ...

  2. Body mass index and skinfolds as indicators of obesity in schoolchildren aged 8 to 10 years

    Directory of Open Access Journals (Sweden)

    Renata Selvatici Borges Januário

    2008-07-01

    Full Text Available http://dx.doi.org/10.5007/1980-0037.2008v10n3p266 The aim of this study was to compare the concordance of two obesity indicators, BMI and % body fat in boys and girls. Therefore, 100 girls and 100 boys, with ages ranging from 8 to 10 years, were submitted to anthropometric measurements for subsequent calculation of Body Mass Index (BMI and % body fat, both as obesity indicators. The variables were analyzed with relation to the reference criteria proposed by Williams et al and Cole et al. The results were then analyzed with the kappa index, elucidating that 79% of the boys and 85% of the girls were classified simultaneously by both procedures. The kappa index indicated a moderate agreement between the two obesity indicators for obese and non-obese classification. However, our data demonstrated that 21% of the boys and 15% of the girls showed normal weight according to BMI, but were classified as obese according to the % body fat. The results show that BMI, when compared with skinfolds, had moderate agreement in children from 8 to 10 years old for detecting obesity.

  3. Validity of Skinfold Equations, Against Dual-Energy X-Ray Absorptiometry, in Predicting Body Composition in Adolescent Pentathletes.

    Science.gov (United States)

    Fonseca-Junior, Sidnei Jorge; Oliveira, Aldair J; Loureiro, Luiz Lannes; Pierucci, Anna Paola Trindade

    2017-05-01

    Body composition of adolescent athletes is often evaluated scientifically and in sports by using reference equations developed from nonathlete adolescent populations. The aim of this study was to analyze the validity of predictive equations based on skinfold measurements, as compared with dual-energy X-ray absorptiometry (DXA), to estimate body fat in adolescent modern pentathlon athletes. 51 athletes, 27 male (mean age = 15.1 years; standard deviation, SD = 1.5 years) and 24 female (mean age = 14.2 years; SD = 2.5 years), were assessed using DXA, anthropometric parameters, sports practice anamnesis, and pubertal stages. Agreement between methods was tested with boxplots of mean comparisons using Student's t test (p .05), but they did display high variability (2SD). The high variability among results indicated imprecision. Predictive skinfold equations developed for nonathlete adolescents do not offer good validity for modern adolescent pentathlon athletes, and should be avoided.

  4. Skinfold anthropometry--the accurate method for fat free mass measurement in COPD.

    Science.gov (United States)

    Hronek, Miloslav; Kovarik, Miroslav; Aimova, Petra; Koblizek, Vladimir; Pavlikova, Ladislava; Salajka, Frantisek; Zadak, Zdenek

    2013-10-01

    Fat free mass index (FFMI) is an independent predictor of metabolic and functional consequences in COPD. For its measurement dual energy X-ray absorptiometry (DEXA), skin-fold anthropometry (SFA), bioelectrical impedance analysis (BIA) and bioimpedance spectroscopy (BIS) are used in clinical practice. The aim of our pilot study was to analyse precisely and critically which method is most accurate and available for common use in clinical practice for measurement of FFM by assessment against relevant DEXA in patients with COPD. This was an observational cross-sectional study of consecutive COPD subjects. FFM by methods of SFA, two versions of BIA, and BIS was compared with that from clinically relevant DEXA in 41 outpatients (mean age 66.5 ± 7.7 yrs) with stable COPD, 34 men and 7 women, with mean BMI 28.2 ± 6.1 kg.m(-2). All methods underestimate FFM in comparison with DEXA. In the general evaluation non-significant differences with the smallest mean bias were demonstrated for SFA (1.2 kg) and BIA (3.8 kg), but there was a difference of more than 9 kg using BIS and BIA COPD methods (p DEXA and SFA was demonstrated via Lin's concordance coefficient and Bland-Altman test. SFA has been demonstrated as an accurate, available and cheap method for determination of FFM and FM with application of the Durnin Womersley equation for body density and with the Siri equation for FM in patients with COPD. SFA can be easily applied in routine clinical practice.

  5. Body mass index and skinfolds as indicators of obesity in schoolchildren aged 8 to 10 years

    Directory of Open Access Journals (Sweden)

    João Paulo Buraneli Mantoan

    2008-06-01

    Full Text Available The aim of this study was to compare the concordance of two obesity indicators, BMI and % body fat in boys and girls. Therefore, 100 girls and 100 boys, with ages ranging from 8 to 10 years, were submitted to anthropometric measurements for subsequent calculation of Body Mass Index (BMI and % body fat, both as obesity indicators. The variables were analyzed with relation to the reference criteria proposed by Williams et al and Cole et al. The results were then analyzed with the kappa index, elucidating that 79% of the boys and 85% of the girls were classified simultaneously by both procedures. The kappa index indicated a moderate agreement between the two obesity indicators for obese and non-obese classification. However, our data demonstrated that 21% of the boys and 15% of the girls showed normal weight according to BMI, but were classified as obese according to the % body fat. The results show that BMI, when compared with skinfolds, had moderate agreement in children from 8 to 10 years old for detecting obesity. ResumoO objetivo deste estudo foi comparar a concordância entre dois indicadores de obesidade, IMC e percentual de gordura, em escolares de ambos os sexos. Para tanto, 100 meninas e 100 meninos de 8 a 10 anos, alunos do ensino fundamental do município de Londrina, foram submetidos a medidas antropométricas para subseqüente cálculo do Índice de Massa Corporal (IMC e percentual de gordura como indicadores de obesidade. As variáveis foram analisadas em relação aos critérios de referência apresentados por Williams et al e Cole et al. Os resultados foram analisados pelo índice Kappa, evidenciando que 79% dos meninos e 85% das meninas foram classificados simultaneamente pelos dois procedimentos. Uma concordância moderada entre os dois indicadores de obesidade na classificação para meninos e meninas foi evidenciada (kappa=0,43 e 0,50, respectivamente. Entretanto, os dados encontrados demonstraram que 21% dos meninos e 15% das

  6. Validitas Pengukuran Lemak Tubuh Yang Menggunakan Skinfold Caliper Di 2, 3, 4, 7 Tempat Terhadap Cara Bod Pod

    OpenAIRE

    Budiman, Iwan

    2008-01-01

    Early in the new millennium there is an epidemic of the metabolic syndrome world wide with obesity as the main factor.  Obesity will be accompanied by pathologic conditions like hypertension, glucose intolerance, dyslipidemia and cardiovascular disease. Obesity is excess body fat and body fat can be measured by using Bod Pod which has an accuracy near DEXA’s accuracy. The body fat can also be measured by skinfold caliper with lower accuracy than Bod Pod.  Obesity will always b...

  7. Representational Thickness

    DEFF Research Database (Denmark)

    Mullins, Michael

    to improve design conditions for architects, thereby increasing the “thickness of representation”. The study commences from a broader theoretical enquiry, a review of previous research and examples of relevant context in which virtual reality has been used in practice. It develops from this discussion three......Contemporary communicational and informational processes contribute to the shaping of our physical environment by having a powerful influence on the process of design. Applications of virtual reality (VR) are transforming the way architecture is conceived and produced by introducing dynamic...... elements into the process of design. Through its immersive properties, virtual reality allows access to a spatial experience of a computer model very different to both screen based simulations as well as traditional forms of architectural representation. The dissertation focuses on processes of the current...

  8. Body mass index, waist circumference and skin-fold thickness in 12-to 14-year-old Dutch adolescents: differences between 2003 and 2011

    NARCIS (Netherlands)

    van Nassau, F.; Singh, A.S.; van Mechelen, W.; Brug, J.; Chin A Paw, M.J.M.

    2014-01-01

    Objectives The aim of this study was to compare anthropometrics of 12- to 14-year-old Dutch adolescents attending lower levels of education in 2011 with adolescents measured in 2003. Methods We used baseline data from two trials evaluating a school-based obesity prevention programme in 2003

  9. Assessment of nutritional status in adult patients with cystic fibrosis: whole-body bioimpedance vs body mass index, skinfolds, and leg-to-leg bioimpedance

    NARCIS (Netherlands)

    Hollander, F.M.; Roos, de N.M.; Vries, de J.H.M.; Berkhout, van F.T.

    2005-01-01

    Objective: To investigate whether body mass index (BMI) or body fat percentage estimated from BMI, skinfolds, or leg-to-leg bioimpedance are good indicators of nutritional status in adult patients with cystic fibrosis. Body fat percentage measured by whole-body bioimpedance was used as the reference

  10. Anthropometric and training variables related to half-marathon running performance in recreational female runners.

    Science.gov (United States)

    Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Rosemann, Thomas

    2011-05-01

    The relationship between skin-fold thickness and running has been investigated in distances ranging from 100 m to the marathon distance (42.195 km), with the exclusion of the half-marathon distance (21.0975 km). We investigated the association between anthropometric variables, prerace experience, and training variables with race time in 42 recreational, nonprofessional, female half-marathon runners using bi- and multivariate analysis. Body weight (r, 0.60); body mass index (r, 0.48); body fat percentage (r, 0.56); pectoral (r, 0.61), mid-axilla (r, 0.69), triceps (r, 0.49), subscapular (r, 0.61), abdominal (r, 0.59), suprailiac (r, 0.55), and medial calf (r, 0.53) skin-fold thickness; mean speed of the training sessions (r, -0.68); and personal best time in a half-marathon (r, 0.69) correlated with race time after bivariate analysis. Body weight (P = 0.0054), pectoral skin-fold thickness (P = 0.0068), and mean speed of the training sessions (P = 0.0041) remained significant after multivariate analysis. Mean running speed during training was related to mid-axilla (r, -0.31), subscapular (r, -0.38), abdominal (r, -0.44), and suprailiac (r, -0.41) skin-fold thickness, the sum of 8 skin-fold thicknesses (r, -0.36); and percent body fat (r, -0.31). It was determined that variables of both anthropometry and training were related to half-marathon race time, and that skin-fold thicknesses were associated with running speed during training. For practical applications, high running speed during training (as opposed to extensive training) may both reduce upper-body skin-fold thicknesses and improve race performance in recreational female half-marathon runners.

  11. Nutritional status in mentally disabled children and adolescents: A study from Western Turkey

    OpenAIRE

    Hakime Nogay, Nalan

    2013-01-01

    Objective: To assess the nutritional status of mentally disabled children in Turkey on the basis of anthropometric indicators and dietary intake. Methodology: The sample of the study consisted of 77 mentally disabled children with ages between 10 and 18 years. The body mass index and body fat ratios of the children were calculated by measuring their body weight, height, and the skinfold thickness of their triceps and subscapular. Their three-day nutrition consumption was recorded in order to ...

  12. Skinfold Prediction Equations Fail to Provide an Accurate Estimate of Body Composition in Elite Rugby Union Athletes of Caucasian and Polynesian Ethnicity.

    Science.gov (United States)

    Zemski, Adam J; Broad, Elizabeth M; Slater, Gary J

    2018-01-01

    Body composition in elite rugby union athletes is routinely assessed using surface anthropometry, which can be utilized to provide estimates of absolute body composition using regression equations. This study aims to assess the ability of available skinfold equations to estimate body composition in elite rugby union athletes who have unique physique traits and divergent ethnicity. The development of sport-specific and ethnicity-sensitive equations was also pursued. Forty-three male international Australian rugby union athletes of Caucasian and Polynesian descent underwent surface anthropometry and dual-energy X-ray absorptiometry (DXA) assessment. Body fat percent (BF%) was estimated using five previously developed equations and compared to DXA measures. Novel sport and ethnicity-sensitive prediction equations were developed using forward selection multiple regression analysis. Existing skinfold equations provided unsatisfactory estimates of BF% in elite rugby union athletes, with all equations demonstrating a 95% prediction interval in excess of 5%. The equations tended to underestimate BF% at low levels of adiposity, whilst overestimating BF% at higher levels of adiposity, regardless of ethnicity. The novel equations created explained a similar amount of variance to those previously developed (Caucasians 75%, Polynesians 90%). The use of skinfold equations, including the created equations, cannot be supported to estimate absolute body composition. Until a population-specific equation is established that can be validated to precisely estimate body composition, it is advocated to use a proven method, such as DXA, when absolute measures of lean and fat mass are desired, and raw anthropometry data routinely to derive an estimate of body composition change.

  13. Education and "Thick" Epistemology

    Science.gov (United States)

    Kotzee, Ben

    2011-01-01

    In this essay Ben Kotzee addresses the implications of Bernard Williams's distinction between "thick" and "thin" concepts in ethics for epistemology and for education. Kotzee holds that, as in the case of ethics, one may distinguish between "thick" and "thin" concepts of epistemology and, further, that this distinction points to the importance of…

  14. In vivo quantification of mTHPC fluorescence in skinfold observation chamber using excitation and detection towards the near infrared region

    Science.gov (United States)

    Kascáková, Slávka; de Visscher, Sebastiaan; Kruijt, Bastiaan; de Bruijn, Henriëtte S.; van der Ploeg-van den Heuvel, Angélique; Sterenborg, Henricus J. C. M.; Witjes, Max J. H.; Amelink, Arjen; Robinson, Dominic J.

    2009-06-01

    In this study, a ratiometric quantification method is developed and applied to monitor mesotetra(hydroxyphenyl) chlorin (mTHPC) pharmacokinetics in the rat skin-fold observation chamber. The method employs a combination of dual-wavelength excitation and dual-wavelength detection. The excitation and detection wavelengths were selected in close to NIR. The first excitation wavelength was used to excite the mTHPC and autofluorescence and the second to excite only autofluorescence, so that this could be substracted. Subsequently the difference was divided by the autofluorescence. Since the method applies division of signal with no mTHPC fluorescence, theory suggests on linear dependency of the method on photosensitizer concentration.

  15. Comparison of body mass index with waist circumference and skinfold-based percent body fat in firefighters: adiposity classification and associations with cardiovascular disease risk factors.

    Science.gov (United States)

    Choi, BongKyoo; Steiss, Dale; Garcia-Rivas, Javier; Kojaku, Stacey; Schnall, Peter; Dobson, Marnie; Baker, Dean

    2016-04-01

    This study aims to examine whether body mass index (BMI) overestimates the prevalence of overweight or obese firefighters when compared to waist circumference (WC) and skinfold-based percent body fat (PBF) and to investigate differential relationships of the three adiposity measures with other biological cardiovascular disease (CVD) risk factors. The adiposity of 355 (347 males and eight females) California firefighters was assessed using three different measures. Other CVD risk factors (high blood pressure, high lipid profiles, high glucose, and low VO2 max) of the firefighters were also clinically assessed. The prevalence of total overweight and obesity was significantly (p BMI (80.4 %) than by WC (48.7 %) and by PBF (55.6 %) in male firefighters. In particular, the prevalence of overweight firefighters was much higher (p BMI (57.3 %) than by WC (24.5 %) and PBF (38.3 %). 60-64 % of male firefighters who were assessed as normal weight by WC and PBF were misclassified as overweight by BMI. When overweight by BMI was defined as 27.5-29.9 kg/m(2) (vs. the standard definition of 25.0-29.9 kg/m(2)), the agreement of the adiposity classification increased between BMI and other two adiposity measures. Obese firefighters had the highest CVD risk profiles across all three adiposity measures. Only when overweight by BMI was defined narrowly, overweight firefighters had substantially higher CVD risk profiles. Obesity and overweight were less prevalent in female and Asian male firefighters. BMI overestimated the prevalence of total overweight and obesity among male firefighters, compared to WC and skinfold-based PBF. Overweight by BMI needs to be more narrowly defined, or the prevalence of BMI-based overweight (27.5-29.9 kg/m(2)) should be reported additionally for prevention of CVD among male firefighters.

  16. Ocean Sediment Thickness Contours

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ocean sediment thickness contours in 200 meter intervals for water depths ranging from 0 - 18,000 meters. These contours were derived from a global sediment...

  17. Relationship between in utero sonographic evaluation and subcutaneous plicometry after birth in infants with intrauterine growth restriction: an exploratory study

    Directory of Open Access Journals (Sweden)

    Giannì Maria L

    2010-10-01

    Full Text Available Abstract Background Intrauterine growth restriction (IUGR is associated with several medical complications before and after delivery. The aim of this study was to evaluate the concordance between the fetal ultrasonographic measurement of subcutaneous tissue thicknesses and the skinfold thicknesses assessment in intrauterine growth restricted newborns. Methods We designed an exploratory study. Fetal ultrasonographic measurement of subcutaneous tissue thicknesses, according to Bernstein's and Galan's method, and neonatal skinfold thicknesses were evaluated in 13 intrauterine growth restricted newborns within 4 hours before delivery and on the first day of life, respectively. Concordance between fetal and neonatal measurements was assessed using the Lin's correlation coefficient and the Bland-Altman method. Results The data obtained by the measurements of neonatal skinfold thicknesses was significantly correlated with the prenatal measurements (Lin's coefficients, arm: 0.60; subscapular: 0.72; abdomen: 0.51. Bland-Altman analysis showed moderate agreement between the fetal ultrasonographic measurement of subcutaneous tissue thicknesses and the neonatal skinfold thicknesses assessment. Conclusions The present study provides preliminary evidence that fetal sonographic measurements may represent additional indices of intrauterine growth restriction.

  18. Growth and nutritional status of children with congenital heart disease.

    Science.gov (United States)

    da Silva, Viviane Martins; de Oliveira Lopes, Marcos Venícios; de Araujo, Thelma Leite

    2007-01-01

    Factors predictive of growth deficit and nutritional status in children with congenital heart disease remain unclear. The objective of this study was to characterize the growth and nutritional status of children with congenital heart disease based on anthropometric measurements and z scores. One hundred and thirty-five children 1 year or younger, who had not undergone surgical correction, were evaluated. The variables studied were sex; age; type of heart disease; length, weight; z scores (length-for-age, weight-for-age, weight-for-length); abdominal, thoracic, and cephalic circumferences; triceps and subscapular skinfold thickness; and birth weight and birth length. The mean age of children in this study was 4.75 +/- 3.75 months and most (66.7%) were male. Mean anthropometric measurements were birth length, 48.6 +/- 2.34 cm; birth weight, 3.11 +/- 0.63 kg; cephalic circumference, 38.51 +/- 3.28 cm; thoracic circumference, 38.65 +/- 3.76 cm; abdominal circumference, 37.96 +/- 3.27 cm; triceps skinfold thickness, 3.69 +/- 1.57 mm; subscapular skinfold thickness, 3.22 +/- 1.34 mm; current length, 57.54 +/- 7.87 cm; and current weight, 4.46 +/- 1.49 kg. Variables significant for malnutrition in logistic regression models were sex, type of heart disease, birth weight, birth length, subscapular thickness, triceps thickness, and cephalic circumference. Nutritional defects were more evident in the case of the weight-for-age index. Boys had greater deterioration in the weight-for-age index, possibly indicating acute malnutrition, and girls had worse values for the height-for-age index, indicating a risk of chronic malnutrition.

  19. Sub-cutaneous fat thickness measured by magnetic resonance imaging, ultrasound, and calipers.

    Science.gov (United States)

    Hayes, P A; Sowood, P J; Belyavin, A; Cohen, J B; Smith, F W

    1988-06-01

    Sub-cutaneous fat thickness was measured at 12 sites on the body surface of 24 males and 26 females using magnetic resonance imaging (MRI), skinfold calipers, and A-mode ultrasound. The mean of the 12 fat thickness measurements and individual site thicknesses were compared between individuals using analysis of variance. In males, the mean thicknesses for ultrasound and calipers were similar (P greater than 0.05) but both were less than the MRI (P less than 0.001). MRI and ultrasound were similar in females but less than calipers (P less than 0.001). A good between-subject correlation was found between all three methods in the males but only the calipers and MRI were well correlated in females. Within-subject correlations are poor for all measures and in both sexes. Factor loadings for a varimax rotation of two principal components indicate that the fat is distributed in 1 of 2 patterns: either principally on the trunk or on the limbs. The principal component analysis and the result of canonical correlations obtained from the factor loadings confirm the findings of the analysis of variance, in that a general level of fatness is measurable by all three methods over a range of subjects. However, the pattern of fat thicknesses measured over a number of specific sites by one method of measurement is unlikely to be duplicated by either of the other two methods on the same individual.

  20. Delays in thick targets

    CERN Document Server

    Bennett, J R J

    2002-01-01

    The delays in the emission of radioactive particles from a thick target bombarded by high-energy protons is discussed in relation to the basic physical processes of diffusion and effusion through the target and ioniser. The delay time, relative to the decay time, is crucial to the efficiency of particle release at the exit of the ioniser. The principles of minimizing the delay times are discussed with reference to a mathematical model of the process, and some experimental examples are given.

  1. Anthropometry and physical activity level in the prediction of metabolic syndrome in children.

    Science.gov (United States)

    Andaki, Alynne Christian Ribeiro; Tinôco, Adelson Luiz Araújo; Mendes, Edmar Lacerda; Andaki Júnior, Roberto; Hills, Andrew P; Amorim, Paulo Roberto S

    2014-10-01

    To evaluate the effectiveness of anthropometric measures and physical activity level in the prediction of metabolic syndrome (MetS) in children. Cross-sectional study with children from public and private schools. Children underwent an anthropometric assessment, blood pressure measurement and biochemical evaluation of serum for determination of TAG, HDL-cholesterol and glucose. Physical activity level was calculated and number of steps per day obtained using a pedometer for seven consecutive days. Viçosa, south-eastern Brazil. Boys and girls (n 187), mean age 9·90 (SD 0·7) years. Conicity index, sum of four skinfolds, physical activity level and number of steps per day were accurate in predicting MetS in boys. Anthropometric indicators were accurate in predicting MetS for girls, specifically BMI, waist circumference measured at the narrowest point and at the level of the umbilicus, four skinfold thickness measures evaluated separately, the sum of subscapular and triceps skinfold thickness, the sum of four skinfolds and body fat percentage. The sum of four skinfolds was the most accurate method in predicting MetS in both genders.

  2. Secular Changes of Adiposity in Czech Children Aged from 3 to 6 Years: Latent Obesity in Preschool Age

    Directory of Open Access Journals (Sweden)

    Petr Sedlak

    2017-01-01

    Full Text Available BMI, skinfold thickness, and circumferential measures were assessed in groups of normal healthy Czech boys (n=1764 and girls (n=1762 3–6 years of age in the late 1950s and 1960s (sample C, in the 1990s (sample B, and in 2014–2016 (sample A. During these decades BMI has not changed significantly, and in selected groups (boys 3, 5, and 6, girls 3 and 6 years it was most recently found to be significantly lower (P≤0.05. Subscapular, suprailiac, triceps, midthigh, and above patella skinfold thicknesses significantly increased in sample A as compared to sample C (P≤0.001. Comparison of the same skinfolds measured in the nineties (sample B and more recently (sample A showed similar increase of subcutaneous fat (P≤0.001. The increase of adiposity characterized by skinfolds occurring in spite of not markedly changed BMI indicates significant changes of body composition—latent (also hidden obesity. The increase of adiposity was relatively greatest on the trunk (P≤0.001—which is considered a marker of the greatest health risk. The decrease of femoral circumference (P≤0.05 along with simultaneous increase of thigh skinfold (P≤0.01 revealed the decrease of muscle mass in the lower extremity, obviously due to the reduction of weight-transferring physical activity.

  3. Predictor variables for half marathon race time in recreational female runners

    Directory of Open Access Journals (Sweden)

    Beat Knechtle

    2011-01-01

    Full Text Available INTRODUCTION: The relationship between skin-fold thickness and running performance has been investigated from 100 m to the marathon distance, except the half marathon distance. OBJECTIVE: To investigate whether anthropometry characteristics or training practices were related to race time in 42 recreational female half marathoners to determine the predictor variables of half-marathon race time and to inform future novice female half marathoners. METHODS: Observational field study at the 'Half Marathon Basel' in Switzerland. RESULTS: In the bivariate analysis, body mass (r = 0.60, body mass index (r = 0.48, body fat (r = 0.56, skin-fold at pectoral (r = 0.61, mid-axilla (r = 0.69, triceps (r = 0.49, subscapular (r = 0.61, abdominal (r = 0.59, suprailiac (r = 0.55 medial calf (r = 0.53 site, and speed of the training sessions (r = -0.68 correlated to race time. Mid-axilla skin-fold (p = 0.04 and speed of the training sessions (p = 0.0001 remained significant after multi-variate analysis. Race time in a half marathon might be predicted by the following equation (r² = 0.71: Race time (min = 166.7 + 1.7x (mid-axilla skin-fold, mm - 6.4x (speed in training, km/h. Running speed during training was related to skinfold thickness at mid-axilla (r = -0.31, subscapular (r = -0.38, abdominal (r = -0.44, suprailiacal (r = -0.41, the sum of eight skin-folds (r = -0.36 and percent body fat (r = -0.31. CONCLUSION: Anthropometric and training variables were related to half-marathon race time in recreational female runners. Skin-fold thicknesses at various upper body locations were related to training intensity. High running speed in training appears to be important for fast half-marathon race times and may reduce upper body skin-fold thicknesses in recreational female half marathoners.

  4. Predictor variables for half marathon race time in recreational female runners.

    Science.gov (United States)

    Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Rosemann, Thomas; Lepers, Romuald

    2011-01-01

    The relationship between skin-fold thickness and running performance has been investigated from 100 m to the marathon distance, except the half marathon distance. To investigate whether anthropometry characteristics or training practices were related to race time in 42 recreational female half marathoners to determine the predictor variables of half-marathon race time and to inform future novice female half marathoners. Observational field study at the 'Half Marathon Basel' in Switzerland. In the bivariate analysis, body mass (r = 0.60), body mass index (r = 0.48), body fat (r = 0.56), skin-fold at pectoral (r = 0.61), mid-axilla (r = 0.69), triceps (r = 0.49), subscapular (r = 0.61), abdominal (r = 0.59), suprailiac (r = 0.55) medial calf (r = 0.53) site, and speed of the training sessions (r = -0.68) correlated to race time. Mid-axilla skin-fold (p = 0.04) and speed of the training sessions (p = 0.0001) remained significant after multi-variate analysis. Race time in a half marathon might be predicted by the following equation (r² = 0.71): Race time (min) = 166.7 + 1.7x (mid-axilla skin-fold, mm) - 6.4x (speed in training, km/h). Running speed during training was related to skinfold thickness at mid-axilla (r = -0.31), subscapular (r = -0.38), abdominal (r = -0.44), suprailiacal (r = -0.41), the sum of eight skin-folds (r = -0.36) and percent body fat (r = -0.31). Anthropometric and training variables were related to half-marathon race time in recreational female runners. Skin-fold thicknesses at various upper body locations were related to training intensity. High running speed in training appears to be important for fast half-marathon race times and may reduce upper body skin-fold thicknesses in recreational female half marathoners.

  5. [ALPHA-fitness test battery: health-related field-based fitness tests assessment in children and adolescents].

    Science.gov (United States)

    Ruiz, J R; España Romero, V; Castro Piñero, J; Artero, E G; Ortega, F B; Cuenca García, M; Jiménez Pavón, D; Chillón, P; Girela Rejón, Ma J; Mora, J; Gutiérrez, A; Suni, J; Sjöstrom, M; Castillo, M J

    2011-01-01

    Hereby we summarize the work developed by the ALPHA (Assessing Levels of Physical Activity) Study and describe the tests included in the ALPHA health-related fitness test battery for children and adolescents. The evidence-based ALPHA-Fitness test battery include the following tests: 1) the 20 m shuttle run test to assess cardiorespiratory fitness; 2) the handgrip strength and 3) standing broad jump to assess musculoskeletal fitness, and 4) body mass index, 5) waist circumference; and 6) skinfold thickness (triceps and subscapular) to assess body composition. Furthermore, we include two versions: 1) the high priority ALPHA health-related fitness test battery, which comprises all the evidence-based fitness tests except the measurement of the skinfold thickness; and 2) the extended ALPHA health-related fitness tests battery for children and adolescents, which includes all the evidence-based fitness tests plus the 4 x 10 m shuttle run test to assess motor fitness.

  6. Nutritional status of children with congenital heart disease.

    Science.gov (United States)

    Monteiro, Flávia Paula Magalhães; de Araujo, Thelma Leite; Lopes, Marcos Venícios de Oliveira; Chaves, Daniel Bruno Resende; Beltrão, Beatriz Amorim; Costa, Alice Gabrielle de Sousa

    2012-01-01

    to characterize nutritional status and variables that predict nutritional changes in children with congenital heart disease. a cross-sectional study undertaken in two health institutions between January and June 2009, using a questionnaire with questions about nutrition, applied to 132 children under two years of age who had congenital heart disease. Children who had additional serious illnesses were excluded. the predominant percentile values and Z scores were concentrated within the range of normal levels. The Z scores, however, presented negative variations with a deviation to the left. In the analysis of predictive factors, the occurrence of immediate and acute malnutrition was related to a decrease in skinfold thickness (decrease in subscapular skinfold thickness, while immediate malnutrition was related to a high Apgar score. Chronic malnutrition was related to female children with higher ages. it is evidenced that it is necessary to carry out nutritional strategies which improve prognosis, so as to widen the nursing care directed at these children.

  7. A sibling-pair analysis of fasting lipids and anthropometric measurements and their relationship to hypertension.

    Science.gov (United States)

    Thomas, G N; Young, R P; Tomlinson, B; Anderson, P J; Woo, K S; Sanderson, J E; Critchley, J A

    1999-10-01

    Fifty non-diabetic, young Chinese hypertensives were compared to their normotensive siblings with respect to body fat distribution and fasting lipid and glucose (FPG) profiles. Sitting BP in hypertensives met conventional hypertension criteria after a 4-week washout period on placebo. Hypertensives had greater body mass index (BMI), subscapular skin-fold thickness (SFT), waist circumference (W), waist-to-height (WHtR) and waist-to-hip ratio (WHR), pobesity, particularly central, is closely associated with hypertension in Chinese as in other ethnic groups.

  8. Predictive capacity of anthropometric indicators for dyslipidemia screening in children and adolescents.

    Science.gov (United States)

    Quadros, Teresa Maria Bianchini; Gordia, Alex Pinheiro; Silva, Rosane Carla Rosendo; Silva, Luciana Rodrigues

    2015-01-01

    To analyze the predictive capacity of anthropometric indicators and their cut-off values for dyslipidemia screening in children and adolescents. This was a cross-sectional study involving 1139 children and adolescents, of both sexes, aged 6-18 years. Body weight, height, waist circumference, subscapular, and triceps skinfold thickness were measured. The body mass index and waist-to-height ratio were calculated. Children and adolescents exhibiting at least one of the following lipid alterations were defined as having dyslipidemia: elevated total cholesterol, low high-density lipoprotein, elevated low-density lipoprotein, and high triglyceride concentration. A receiver operating characteristic curve was constructed and the area under the curve, sensitivity, and specificity was calculated for the parameters analyzed. The prevalence of dyslipidemia was 62.1%. The waist-to-height ratio, waist circumference, subscapular, body mass index, and triceps skinfold thickness, in this order, presented the largest number of significant accuracies, ranging from 0.59 to 0.78. The associations of the anthropometric indicators with dyslipidemia were stronger among adolescents than among children. Significant differences between accuracies of the anthropometric indicators were only observed by the end of adolescence; the accuracy of waist-to-height ratio was higher than that of subscapular (p=0.048) for females, and the accuracy of waist circumference was higher than that of subscapular (p=0.029) and body mass index (p=0.012) for males. In general, the cut-off values of the anthropometric predictors of dyslipidemia increased with age, except for waist-to-height ratio. Sensitivity and specificity varied substantially between anthropometric indicators, ranging from 75.6 to 53.5 and from 75.0 to 50.0, respectively. The anthropometric indicators studied had little utility as screening tools for dyslipidemia, especially in children. Copyright © 2015 Sociedade Brasileira de Pediatria

  9. Disentangling The Thick Concept Argument

    DEFF Research Database (Denmark)

    Blomberg, Olle

    2007-01-01

    Critics argue that non-cognitivism cannot adequately account for the existence and nature of some thick moral concepts. They use the existence of thick concepts as a lever in an argument against non-cognitivism, here called the Thick Concept Argument (TCA). While TCA is frequently invoked...

  10. Thick Disks of Lenticular Galaxies

    OpenAIRE

    Pohlen, M.; Balcells, M.; Luetticke, R.; Dettmar, R. -J.

    2004-01-01

    Thick disks are faint and extended stellar components found around several disk galaxies including our Milky Way. The Milky Way thick disk, the only one studied in detail, contains mostly old disk stars (~10 Gyr), so that thick disks are likely to trace the early stages of disk evolution. Previous detections of thick disk stellar light in external galaxies have been originally made for early-type, edge-on galaxies but detailed 2D thick/thin disk decompositions have been reported for only a sc...

  11. Changes in total and central adiposity and body fat distribution among 7-10-year-old schoolchildren in Brazil.

    Science.gov (United States)

    Leal, Danielle Biazzi; de Assis, Maria Alice Altenburg; González-Chica, David Alejandro; da Costa, Filipe Ferreira; de Andrade, Dalton Francisco; Lobo, Adriana Soares

    2015-08-01

    To describe changes in total and central adiposity and body fat distribution in children over a 5-year period by investigating variations in BMI, waist circumference (WC), waist-to-height ratio (WHtR) and skinfold thicknesses (SFT). A school-based sample of children from 2nd to 5th grades of elementary schools participated in two cross-sectional studies in 2002 (n 2936) and 2007 (n 1232). Public and private schools of Florianopolis, Brazil. Schoolchildren aged 7-10 years had their weight, height, WC and SFT measured according to standard procedures. Body fat distribution was assessed by triceps, subscapular, suprailiac and medial calf skinfold measurements. Changes in BMI, WC, WHtR and SFT were analysed, adjusting for type of school and monthly family income. Adjusted mean differences between 2002 and 2007 for BMI and WC were always positive and of similar magnitude between boys and girls. However, a statistically significant increase was observed only for BMI (raw and Z-score values) in boys. WHtR remained stable in both sexes. Adjusted median values for SFT also increased in boys and girls, except for triceps skinfold. BMI, WC and SFT tended to increase across age classes in both sexes. The relative change observed for the median central skinfolds (subscapular and suprailiac) was greater than that of peripheral skinfolds (triceps and medial calf). The subcutaneous adipose tissue (SFT) appeared to increase at a faster rate than total adiposity (BMI). The increase in central SFT indicates that the relative change is due primarily to a rise in central adiposity.

  12. Antropometric measurements and body composition of English and Malaysian footballers.

    Science.gov (United States)

    Reeves, S; Poh, B; Brown, M; Tizzard, N; Ismail, M

    1999-12-01

    This comparative study was conducted to determine the anthropometric measurements and body composition of football teams in the UK and Malaysia. A total of 32 footballers from two teams were studied. The teams were the St Mary's University team (UK) and the Selangor Reserved League team. The height and body weight of the subjects were measured using SECA digital balance with height attachment. Skinfold thickness measurements were taken using Harpenden skinfold callipers at four sites (biceps, triceps, subscapular and suprailiac) and the VO2max of the subjects was estimated by participation in a multi-stage 20m shuttle-run test. The UK team were significantly heavier (pbody fat content (pbody weights. More data on the body composition and nutritional status of Malaysian footballers would allow adjustments to be made to dietary intakes and training levels in order to obtain maximum performance throughout the football season.

  13. Static and dynamic through thickness lamina properties of thick laminates

    NARCIS (Netherlands)

    Lahuerta, F.; Nijssen, R.P.L.; Van der Meer, F.P.; Sluys, L.J.

    2015-01-01

    Thick laminates are increasingly present in large composites structures such as wind turbine blades. Different factors are suspected to be involved in the decreased static and dynamic performance of thick laminates. These include the effect of self-heating, the scaling effect, and the manufacturing

  14.  Soft Tissue Swelling at the Subscapular Region

    Directory of Open Access Journals (Sweden)

    Masoud Al Kindi

    2012-03-01

    Full Text Available A 38-year-old female presented with a longstanding painless swelling overlying the scapula on the right side and has been gradually increasing in size with occasional episodes of pain radiating to the right arm. The clinical diagnosis was a soft tissue tumor. MRI was reported as suggestive of irregular fibro-fatty tissue with muscular infiltration and inflammation. Fine needle aspiration (FNA retrieved a paucicellular aspirate with a few clusters of adipocytes. The diagnosis was a lipomatous lesion and excision was advised for histopathological examination. The intraoperative findings showed the tumor located deep into the rhomboids and latissimus dorsi and extending deep into the right scapula. The excised specimen was sent for histopathological examination. 

  15. The nutritional status of children and adolescents with HIV/AIDS on antiretroviral therapy.

    Science.gov (United States)

    Souza, Déborah Teixeira; Rondó, Patrícia Helen Carvalho; Reis, Ligia Cardoso

    2011-02-01

    The objective of this cross-sectional study was to assess the nutritional status of children and adolescents with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) receiving highly active antiretroviral therapy (HAART). One hundred and eighteen subjects aged 6-19 years attending an outpatient clinic in São Paulo city were involved in the study. The following anthropometric measurements were assessed: weight, height, waist circumference and triceps and subscapular skinfold thickness. One (0.9%) adolescent was diagnosed with abdominal obesity based on waist circumference measurement; three (2.5%) adolescents were obese based on subscapular skinfold thickness. According to the body mass index, the population studied was mainly eutrophic. The prevalence of fat redistribution, a characteristic of patients with HIV/AIDS under HAART, was low. We advise the development of further studies to assess the nutritional status of children and adolescents with HIV/AIDS using anthropometric measurements as well as computed tomography to detect fat redistribution.

  16. Childhood Adiposity and Nonalcoholic Fatty Liver Disease in Adulthood.

    Science.gov (United States)

    Yan, Yinkun; Hou, Dongqing; Zhao, Xiaoyuan; Liu, Junting; Cheng, Hong; Wang, Youfa; Mi, Jie

    2017-04-01

    To investigate the association of childhood adiposity and change in adiposity status from childhood to adulthood with nonalcoholic fatty liver disease (NAFLD) and abnormal liver enzyme levels in adulthood. Data were obtained from a population-based cohort of children aged 6 to 18 years started in 1987. From 2010 to 2014, 1350 subjects (aged 28-45 years) from the original cohort were followed. Childhood overweight and obesity were defined using BMI and subscapular skinfold thickness, respectively. In adulthood, ultrasound-based NAFLD, abnormal liver enzymes, and related risk factors were assessed. Overweight or obese children were more likely to have adult NAFLD (males: odds ratio [OR] = 2.49 for BMI and 2.78 for subscapular skinfold thickness; females: OR = 3.34 and 3.61; all Ps adulthood, subjects who were obese in adulthood, irrespective of their childhood adiposity status, were more likely to have NAFLD and ALT elevation in adulthood for both sexes. However, subjects who were overweight or obese in childhood but became nonobese in adulthood had similar likelihood of having NAFLD and ALT elevation in adulthood for both sexes. Overweight or obese children are more likely to have NAFLD and ALT elevation in adulthood. However, the risk associated with increased weight during childhood can be mitigated by becoming nonobese in adulthood. Copyright © 2017 by the American Academy of Pediatrics.

  17. Exploring Our Galaxy's Thick Disk

    Science.gov (United States)

    Kohler, Susanna

    2017-12-01

    What is the structure of the Milky Ways disk, and how did it form? A new study uses giant stars to explore these questions.A View from the InsideSchematic showing an edge-on, not-to-scale view of what we think the Milky Ways structurelookslike. The thick disk is shown in yellow and the thin disk is shown in green. [Gaba p]Spiral galaxies like ours are often observed to have disks consisting of two components: a thin disk that lies close to the galactic midplane, and a thick disk that extends above and below this. Past studies have suggested that the Milky Ways disk hosts the same structure, but our position embedded in the Milky Way makes this difficult to confirm.If we can measure the properties of a broad sample of distant tracer stars and use this to better understand the construction of the Milky Ways disk, then we can start to ask additional questions like, how did the disk components form? Formation pictures for the thick disk generally fall into two categories:Stars in the thick disk formed within the Milky Way either in situ or by migrating to their current locations.Stars in the thick disk formed in satellite galaxies around the Milky Way and then accreted when the satellites were disrupted.Scientists Chengdong Li and Gang Zhao (NAO Chinese Academy of Sciences, University of Chinese Academy of Sciences) have now used observations of giant stars which can be detected out to great distances due to their brightness to trace the properties of the Milky Ways thick disk and address the question of its origin.Best fits for the radial (top) and vertical (bottom) metallicity gradients of the thick-disk stars. [Adapted from Li Zhao 2017]Probing OriginsLi and Zhao used data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) in China to examine a sample of 35,000 giant stars. The authors sorted these stars into different disk components halo, thin disk, and thick disk based on their kinematic properties, and then explored how the orbital and

  18. In vivo Quantification of the Effects of Radiation and Presence of Hair Follicle Pores on the Proliferation of Fibroblasts in an Acellular Human Dermis in a Dorsal Skinfold Chamber: Relevance for Tissue Reconstruction following Neoadjuvant Therapy.

    Directory of Open Access Journals (Sweden)

    Mario Vitacolonna

    Full Text Available In neoadjuvant therapy, irradiation has a deleterious effect on neoangiogenesis. The aim of this study was to examine the post-implantation effects of neoadjuvant irradiation on the survival and proliferation of autologous cells seeded onto an acellular human dermis (hAD; Epiflex. Additionally, we examined the influence of dermal hair follicle pores on viability and proliferation. We used dorsal skinfold chambers implanted in rats and in-situ microscopy to quantify cell numbers over 9 days.24 rats received a skinfold chamber and were divided into 2 main groups; irradiated and unirradiated. In the irradiated groups 20Gy were applied epicutaneously at the dorsum. Epiflex pieces were cut to size 5x5mm such that each piece had either one or more visible hair follicle pores, or no such visible pores. Fibroblasts were transduced lentiviral with a fluorescent protein for cell tracking. Matrices were seeded statically with 2.5x104 fluorescent fibroblasts and implanted into the chambers. In each of the two main groups, half of the rats received Epiflex with hair follicle pores and half received Epiflex without pores. Scaffolds were examined in-situ at 0, 3, 6 and 9 days after transplantation. Visible cells on the surface were quantified using ImageJ.In all groups cell numbers were decreased on day 3. A treatment-dependent increase in cell numbers was observed at subsequent time points. Irradiation had an adverse effect on cell survival and proliferation. The number of cells detected in both irradiated and non-irradiated subjects was increased in those subjects that received transplants with hair follicle pores.This in-vivo study confirms that radiation negatively affects the survival and proliferation of fibroblasts seeded onto a human dermis transplant. The presence of hair follicle pores in the dermis transplants is shown to have a positive effect on cell survival and proliferation even in irradiated subjects.

  19. In vivo Quantification of the Effects of Radiation and Presence of Hair Follicle Pores on the Proliferation of Fibroblasts in an Acellular Human Dermis in a Dorsal Skinfold Chamber: Relevance for Tissue Reconstruction following Neoadjuvant Therapy.

    Science.gov (United States)

    Vitacolonna, Mario; Belharazem, Djeda; Maier, Patrick; Hohenberger, Peter; Roessner, Eric Dominic

    2015-01-01

    In neoadjuvant therapy, irradiation has a deleterious effect on neoangiogenesis. The aim of this study was to examine the post-implantation effects of neoadjuvant irradiation on the survival and proliferation of autologous cells seeded onto an acellular human dermis (hAD; Epiflex). Additionally, we examined the influence of dermal hair follicle pores on viability and proliferation. We used dorsal skinfold chambers implanted in rats and in-situ microscopy to quantify cell numbers over 9 days. 24 rats received a skinfold chamber and were divided into 2 main groups; irradiated and unirradiated. In the irradiated groups 20Gy were applied epicutaneously at the dorsum. Epiflex pieces were cut to size 5x5mm such that each piece had either one or more visible hair follicle pores, or no such visible pores. Fibroblasts were transduced lentiviral with a fluorescent protein for cell tracking. Matrices were seeded statically with 2.5x104 fluorescent fibroblasts and implanted into the chambers. In each of the two main groups, half of the rats received Epiflex with hair follicle pores and half received Epiflex without pores. Scaffolds were examined in-situ at 0, 3, 6 and 9 days after transplantation. Visible cells on the surface were quantified using ImageJ. In all groups cell numbers were decreased on day 3. A treatment-dependent increase in cell numbers was observed at subsequent time points. Irradiation had an adverse effect on cell survival and proliferation. The number of cells detected in both irradiated and non-irradiated subjects was increased in those subjects that received transplants with hair follicle pores. This in-vivo study confirms that radiation negatively affects the survival and proliferation of fibroblasts seeded onto a human dermis transplant. The presence of hair follicle pores in the dermis transplants is shown to have a positive effect on cell survival and proliferation even in irradiated subjects.

  20. Defining obesity in children by biological endpoint rather than population distribution.

    Science.gov (United States)

    Dwyer, T; Blizzard, C L

    1996-05-01

    To investigate the association of fatness in children with dyslipoproteinemia and high blood pressure, with the purpose of proposing standards for childhood obesity which are directly related to intermediate biological parameters that predict future disease. A cross-sectional study of a large, nationally representative sample of Australian schoolchildren. 1834 children aged 9 or 15 years, with skinfolds blood lipid measurements on 1144 and with skinfolds and blood pressure measurements on 1757. Skinfolds thicknesses measured at four locations (triceps, biceps, subscapular and suprailiac) using holtain calipers, percent body fat calculated from the sum of four skinfolds, Quetelet's index calculated from weight and height, waist and hip circumferences, plasma total cholesterol and triglycerides determined using a Technicon Autoanalyser II, high density lipoprotein cholesterol (HDLC) analysed following precipitation with heparin manganese, and systolic blood pressure (SBP) measured using a standard mercury sphygmomanometer. For 9 years old girls, 15 year old girls and 9 years old boys, dichotomising their HDLC and SBP measurements by percent body fat defined the two groups most homogeneous in terms of a measure of within-group variation. The cut-points in percent body fat were in the ranges 29-35% (girls) and 17-20% (boys). It is feasible to use the current biomedical status of individual children to define criteria for obesity. A cut-off point of 30% body mass as fat for girls and 20% for boys appears to be an appropriate standard.

  1. Sexual maturation and obesity in 9- and 10-year-old black and white girls: the National Heart, Lung, and Blood Institute Growth and Health Study.

    Science.gov (United States)

    Morrison, J A; Barton, B; Biro, F M; Sprecher, D L; Falkner, F; Obarzanek, E

    1994-06-01

    To assess the relationship between pubertal maturation and obesity in 9- and 10-year-old black and white girls. Cross-sectional analysis of cohort baseline data. A cohort of 2379 girls recruited from selected schools in Richmond, Calif., and greater Cincinnati, Ohio, and from the membership rolls of a prepaid group practice in greater Washington, D.C. Sixty-four percent of black girls had begun pubertal maturation compared with 33% of white girls. In prepubertal girls, racial differences in height, weight, body mass index (kilograms per square meter) and skin-fold thickness were not significant. Within each race, onset of pubertal maturation was associated with greater height, weight, body mass index, and skin-fold measurements. Within 9-year-old girls who had begun pubertal maturation but not reached menarche, black girls were taller and heavier than white girls. Among pubertal but premenarcheal 10-year-old subjects, black girls were taller and heavier and had greater body mass index and subscapular skin-fold values. After analyses were adjusted for pubertal maturation stage by means of pubic hair development, 10-year-old pubertal black girls remained taller and heavier, but racial differences in body mass index and the sum of skin-fold measurements ceased to be significant. These findings suggest that the initiation of racial differences in obesity are related, at least temporally, to pubertal maturation.

  2. The reliability of body mass index in the diagnosis of obesity and metabolic risk in children.

    Science.gov (United States)

    Marković-Jovanović, Snežana R; Stolić, Radojica V; Jovanović, Aleksandar N

    2015-05-01

    Body mass index (BMI) is the most widespread and the simplest method for the evaluation of body mass; it is often used as a sole technique in the diagnosis of obesity in children. The objective of the study was to evaluate the relationship between anthropometric and biochemical parameters and the incidence of the metabolic syndrome in obese children. A total of 110 children, aged 2-17 years, participated in the study. No overweight children (BMI 85-95 percentiles) were included. BMI was interpreted using the 2000 Centers for Disease Control and Prevention Growth Charts. The skinfold measurements were performed using an John Bull British Indicators Ltd. calipers, and interpreted using an the reference table values. In addition to lower sensitivity (mentioned in several earlier studies), BMI also shows a lower specificity in the diagnosis of obesity in children: BMI showed at least 10% of non-concomitance with skinfold thickness and waist circumferences and 8% with waist-to-height ratio. In addition, subscapular skinfold thickness, waist circumference, and waist/height ratio showed stronger correlations with serum insulin levels, low-density lipoprotein cholesterol, and family history than BMI itself. The unreliability of BMI as the sole parameter for diagnosing obesity in children was found in our study. Even when overweight children were excluded from the study, the lack of specificity of BMI was demonstrated. We propose utilization of waist circumference and waist/height ratio along with the BMI for definitive diagnosis instead of relying on BMI only. In addition, waist circumference and subscapular fold thickness may be even better in estimation of metabolic risk than BMI.

  3. Analysis of selected anthropometric parameters of 6-year-old children in Warsaw compared to the peer population in the years 1996-1999.

    Science.gov (United States)

    Trzcińska, Dorota; Tabor, Piotr; Olszewska, Elżbieta

    2012-01-01

    Beside the positive tendencies in somatic development seen in the population of children and adolescents in Poland (e.g. the trend of increasing body height that has continued over many years), certain unfavorable phenomena are also observed. In recent decades, disorders connected with a deficiency or excess of body mass - excessive adiposity in particular - have become important health and social problems. This poses a considerable threat for being overweight, for obesity, and for other diseases of civilization. The research targeted the evaluation of selected anthropometric parameters: height-weight indices, circumferences, and skinfold thicknesses in the population of 6-year-old children in Warsaw in comparison with their peer population in 1996-1999, as well as estimation of the frequency of abnormal percentile values of the aforementioned anthropometric parameters: values below the 10th percentile and above the 90th percentile. The research included a sample of 160 randomly chosen children (81 boys and 79 girls) born in 2005 who attended public and private kindergartens in Warsaw. The average age of this group was 5.71 ± 0.28 years. The study was carried out in the first quarter of 2011. The following somatic parameters were measured: body height, body mass, chest and arm circumference, triceps, and subscapular and abdominal skinfold thickness. The height-weight indices including Rohrer's Index and Body Mass Index (BMI) were calculated. Using a method of normalization of numerical data, the obtained measurements were compared to the measurements of the peer population (n=233) from 1996 to 1999, and the significance of differences between mean values in both groups was assessed with Student's t-tests. The percentage tables with the ranges of the below normative (percentile) and above normative (>90th percentile) percentile values of the studied parameters and indices were prepared on the basis of the percentile charts that presented the anthropometric

  4. Application of weight-height relations for assessing adiposity in a United Kingdom offshore workforce.

    Science.gov (United States)

    Light, I M; Gibson, M G

    1987-01-01

    Weight (W), height (H), and skinfold thicknesses at biceps, triceps, subscapular, and suprailiac sites were measured in a United Kingdom offshore workforce. Weight and height were used to calculate W/H relations. The percentage body fat was estimated from skinfold thicknesses and the correlations of adiposity with the various W/H relations were evaluated. The significant increase in percentage body fat (%BF) with increasing age resulted in the development of age group specific regression equations relating %BF to the indices of W/H1.5 and W/H2 (body mass index or Quetelet index). Little difference regarding the qualities of these two indices were detected in terms of poor correlation with height and strong correlation with weight. Thus either may be used with similar levels of confidence. Comparison with other studies, however, would be more easily accomplished if W/H2 were used. In the absence of skinfold thickness measurements the W/H2 could readily be implemented during a routine medical and applied for the estimation of %BF in the offshore population provided that the appropriate regression equation were used and that the limitations of the technique are recognised. Percentage values for W, H, W/H relations, and %BF by age group are provided for comparison with other population studies. PMID:3828245

  5. Thick resist for MEMS processing

    Science.gov (United States)

    Brown, Joe; Hamel, Clifford

    2001-11-01

    The need for technical innovation is always present in today's economy. Microfabrication methods have evolved in support of the demand for smaller and faster integrated circuits with price performance improvements always in the scope of the manufacturing design engineer. The dispersion of processing technology spans well beyond IC fabrication today with batch fabrication and wafer scale processing lending advantages to MEMES applications from biotechnology to consumer electronics from oil exploration to aerospace. Today the demand for innovative processing techniques that enable technology is apparent where only a few years ago appeared too costly or not reliable. In high volume applications where yield and cost improvements are measured in fractions of a percent it is imperative to have process technologies that produce consistent results. Only a few years ago thick resist coatings were limited to thickness less than 20 microns. Factors such as uniformity, edge bead and multiple coatings made high volume production impossible. New developments in photoresist formulation combined with advanced coating equipment techniques that closely controls process parameters have enable thick photoresist coatings of 70 microns with acceptable uniformity and edge bead in one pass. Packaging of microelectronic and micromechanical devices is often a significant cost factor and a reliability issue for high volume low cost production. Technologies such as flip- chip assembly provide a solution for cost and reliability improvements over wire bond techniques. The processing for such technology demands dimensional control and presents a significant cost savings if it were compatible with mainstream technologies. Thick photoresist layers, with good sidewall control would allow wafer-bumping technologies to penetrate the barriers to yield and production where costs for technology are the overriding issue. Single pass processing is paramount to the manufacturability of packaging

  6. The obesity-asthma link in different ages and the role of body mass index in its investigation: findings from the Genesis and Healthy Growth Studies.

    Science.gov (United States)

    Guibas, G V; Manios, Y; Xepapadaki, P; Moschonis, G; Douladiris, N; Mavrogianni, C; Papadopoulos, N G

    2013-10-01

    To date, an obesity/asthma link is well defined in adults; however, the nature of such a link is obscure in children, partly due to Body Mass Index (BMI) limitations as a surrogate fat mass marker in childhood. We thus opted to investigate the association of adiposity with asthma in children of different ages, using several indices to assess fat mass. Wheeze ever/in the last 12 months (current) and physician-diagnosed asthma were retrospectively reported via questionnaire by the parents of 3641 children, participating in two cross-sectional studies: 1626 children aged 2-5 (the Genesis Study) and 2015 children aged 9-13 (the Healthy Growth Study). Perinatal data were recorded from the children's medical records or reported by parents. Anthropometric measurements (i.e., BMI, waist/hip circumference, biceps/triceps/subscapular/suprailiac skinfold thickness) were conducted in both cohorts; bioelectric impedance analysis (BIA) was conducted only in preadolescent children. In children aged 2-5, asthma was positively correlated with conicity index, waist/hip circumference, waist-to-height ratio, skinfold thickness, and skinfold-derived percentage fat mass (P obesity, after adjusting for several confounders. In children aged 9-13, asthma was positively associated with conicity index, waist circumference, waist-to-height ratio, skinfold thickness, skinfold-derived percentage fat mass, BIA-derived percentage fat mass, BMI, and BMI-defined overweight/obesity, following adjustment (P asthma in both 2-5 and 9-13 age spans. However, the failure of BMI to correlate with preschool asthma suggests its potential inefficiency in asthma studies at this age range. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Physical growth assessment in adolescence.

    Science.gov (United States)

    Agarwal, K N; Saxena, A; Bansal, A K; Agarwal, D K

    2001-11-01

    To describe ponderosity indices body mass index--"BMI" and ponderal index "PI" and skin fold thicknesses (triceps, biceps, subscapular and suprailiac) for affluent Indian school going adolescents. Cross sectional. Measurements were recorded in healthy affluent school going adolescents in public schools of 12 cities in India (boys=11,863 and girls 7,694). Means and percentiles of ponderosity indices and skinfold thicknesses at yearly intervals were derived for each sex and related to sexual maturity. BMI, PI and skin fold thickness (SFT) were higher in girls. There was lower variability of these parameters with sexual maturity rating (breast/genital development stages) as compared to age, suggesting use of these indices in relation to sexual maturity for assessment of adolescent growth. Pediatricians and endocrinologists can use these indices for assessment of thinness and obesity, in adolescent Indian children, in relation to sexual maturity for the age.

  8. ANTHROPOMETRICAL STATUS AND GENDER DIFFERENCES AT 12 YEARS OF AGE

    OpenAIRE

    Ilir Gllareva; Besim Halilaj; Bahri Gjinovci; Besnik Morina

    2015-01-01

    The aim of this study is to verify the current anthropometrical status of the pupils of the age 12, as well as to compare it with the standards of raising in accordance with the WHO standards. In the study were included 62 pupils (42 male and 20 female). The anthropometric tests were done in height, weight, biacromial and elbow breadth, subcutaneous adipose tissue at the : suprailiac skinfold; subscapular skinfold; triceps skinfold, as well as the abdominal circumference. The results showed t...

  9. Lonsdaleite Films with Nanometer Thickness.

    Science.gov (United States)

    Kvashnin, Alexander G; Sorokin, Pavel B

    2014-02-06

    We investigate the properties of potentially the stiffest quasi-2-D films with lonsdaleite structure. Using a combination of ab initio and empirical potential approaches, we analyze the elastic properties of lonsdaleite films in both elastic and inelastic regimes and compare them with graphene and diamond films. We review possible fabrication methods of lonsdaleite films using the pure nanoscale "bottom-up" paradigm: by connecting carbon layers in multilayered graphene. We propose the realization of this method in two ways: by applying direct pressure and by using the recently proposed chemically induced phase transition. For both cases, we construct the phase diagrams depending on temperature, pressure, and film thickness. Finally, we consider the electronic properties of lonsdaleite films and establish the nonlinear dependence of the band gap on the films' thicknesses and their lower effective masses in comparison with bulk crystal.

  10. Minimum thickness anterior porcelain restorations.

    Science.gov (United States)

    Radz, Gary M

    2011-04-01

    Porcelain laminate veneers (PLVs) provide the dentist and the patient with an opportunity to enhance the patient's smile in a minimally to virtually noninvasive manner. Today's PLV demonstrates excellent clinical performance and as materials and techniques have evolved, the PLV has become one of the most predictable, most esthetic, and least invasive modalities of treatment. This article explores the latest porcelain materials and their use in minimum thickness restoration. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Soliton models for thick branes

    Energy Technology Data Exchange (ETDEWEB)

    Peyravi, Marzieh [Ferdowsi University of Mashhad, Department of Physics, School of Sciences, Mashhad (Iran, Islamic Republic of); Riazi, Nematollah [Shahid Beheshti University, Physics Department, Tehran (Iran, Islamic Republic of); Lobo, Francisco S.N. [Faculdade de Ciencias da Universidade de Lisboa, Instituto de Astrofisica e Ciencias do Espaco, Lisbon (Portugal)

    2016-05-15

    In this work, we present new soliton solutions for thick branes in 4+1 dimensions. In particular, we consider brane models based on the sine-Gordon (SG), φ{sup 4} and φ{sup 6} scalar fields, which have broken Z{sub 2} symmetry in some cases and are responsible for supporting and stabilizing the thick branes. The origin of the symmetry breaking in these models resides in the fact that the modified scalar field potential may have non-degenerate vacua. These vacua determine the cosmological constant on both sides of the brane. We also study the geodesic equations along the fifth dimension, in order to explore the particle motion in the neighborhood of the brane. Furthermore, we examine the stability of the thick branes, by determining the sign of the w{sup 2} term in the expansion of the potential for the resulting Schroedinger-like equation, where w is the five-dimensional coordinate. It turns out that the φ{sup 4} brane is stable, while there are unstable modes for certain ranges of the model parameters in the SG and φ{sup 6} branes. (orig.)

  12. Ciliary muscle thickness in anisometropia.

    Science.gov (United States)

    Kuchem, Mallory K; Sinnott, Loraine T; Kao, Chiu-Yen; Bailey, Melissa D

    2013-11-01

    The purpose of this study was to investigate the relationships between ciliary muscle thickness (CMT), refractive error, and axial length both across subjects and between the more and less myopic eyes of adults with anisometropia. Both eyes of 29 adult subjects with at least 1.00 D of anisometropia were measured. Ciliary muscle thickness was measured at the maximum thickness (CMTMAX) and at 1.0 (CMT1), 2.0 (CMT2), and 3.0 mm (CMT3) posterior to the scleral spur, and also at the apical region (Apical CMTMAX = CMTMAX - CMT2, and Apical CMT1 = CMT1 - CMT2). Multilevel regression models were used to determine the relationship between the various CMT measures and cycloplegic refractive error or axial length, and to assess whether there are CMT differences between the more and less myopic eyes of an anisometropic adult. CMTMAX, CMT1, CMT2, and CMT3 were negatively associated with mean refractive error (all p ≤ 0.03), and the strongest association was in the posterior region (CMT2 and CMT3). Apical CMTMAX and Apical CMT1, however, were positively associated with mean refractive error (both p anisometropia, an eye can grow longer and more myopic than its fellow eye without resulting in an increase in CMT.

  13. Thick Corpus Callosum in Children.

    Science.gov (United States)

    Schupper, Aviv; Konen, Osnat; Halevy, Ayelet; Cohen, Rony; Aharoni, Sharon; Shuper, Avinoam

    2017-04-01

    A thick corpus callosum (TCC) can be associated with a very grave outcome in fetuses, but its clinical presentation in older children seems to be markedly different. The corpus callosum (CC) was defined as thick based on observations and impressions. We reviewed cases of children who were diagnosed as TCC based on brain magnetic resonance imaging (MRI) studies. The pertinent clinical data of these children were collected, and their CCs were measured. Out of 2,552 brain MRI images, those of 37 children were initially considered as showing a TCC. Those initial imaging were reviewed by an experienced neuroradiologist, who confirmed the diagnosis in 34 children (1.3%): 13 had neurofibromatosis-1 (NF-1), 9 had epilepsy, 3 had macrocephaly capillary malformation (MCM) syndrome, 3 had autistic spectrum disorder, 1 had a Chiari-1 malformation, and 1 had increased head circumference. No specific neurologic disorder could be defined in seven children. The measured thickness of the CC in these children was comparable to those published in the literature for adults. A TCC is a rare brain malformation that can be found in neuropathologies with apparently diverse pathognomonic mechanisms, such as NF-1 and MCM. It is not necessarily associated with life-threatening conditions, instead being a relatively benign finding, different in nature from that reported in fetuses.

  14. Central corneal thickness in glaucoma.

    Science.gov (United States)

    Sng, Chelvin C A; Ang, Marcus; Barton, Keith

    2017-03-01

    The purpose of this review is to summarize the role of central corneal thickness (CCT) in the clinical management of a glaucoma patient. The prognostic value of CCT is well recognized in patients with ocular hypertension. However, its predictive value in other glaucoma suspects and patients with established glaucoma is less certain. Tonometry artefacts can result from variations in CCT. However, an adequately validated correction algorithm for Goldmann applanation tonometry measurements does not exist. Newer methods of tonometry are potentially less influenced by CCT but are limited in their clinical use. There may also be biological and genetic associations between corneal thickness and glaucoma. Demographics, environmental factors, glaucoma treatment and the measurement device used have a significant influence on CCT, and should be considered when interpreting the effect of cornea thickness in patients with glaucoma. New measurements of the biomechanical properties of the cornea are likely to be better approximations of the globe biomechanics than CCT, but these require further evaluation. The clinical significance of CCT is well recognized in the context of glaucoma diagnosis and management, though the extent of its importance remains debatable. Corneal biomechanical properties may be more significantly associated with glaucoma than CCT.

  15. Parametric model of human body shape and ligaments for patient-specific epidural simulation.

    Science.gov (United States)

    Vaughan, Neil; Dubey, Venketesh N; Wee, Michael Y K; Isaacs, Richard

    2014-10-01

    This work is to build upon the concept of matching a person's weight, height and age to their overall body shape to create an adjustable three-dimensional model. A versatile and accurate predictor of body size and shape and ligament thickness is required to improve simulation for medical procedures. A model which is adjustable for any size, shape, body mass, age or height would provide ability to simulate procedures on patients of various body compositions. Three methods are provided for estimating body circumferences and ligament thicknesses for each patient. The first method is using empirical relations from body shape and size. The second method is to load a dataset from a magnetic resonance imaging (MRI) scan or ultrasound scan containing accurate ligament measurements. The third method is a developed artificial neural network (ANN) which uses MRI dataset as a training set and improves accuracy using error back-propagation, which learns to increase accuracy as more patient data is added. The ANN is trained and tested with clinical data from 23,088 patients. The ANN can predict subscapular skinfold thickness within 3.54 mm, waist circumference 3.92 cm, thigh circumference 2.00 cm, arm circumference 1.21 cm, calf circumference 1.40 cm, triceps skinfold thickness 3.43 mm. Alternative regression analysis method gave overall slightly less accurate predictions for subscapular skinfold thickness within 3.75 mm, waist circumference 3.84 cm, thigh circumference 2.16 cm, arm circumference 1.34 cm, calf circumference 1.46 cm, triceps skinfold thickness 3.89 mm. These calculations are used to display a 3D graphics model of the patient's body shape using OpenGL and adjusted by 3D mesh deformations. A patient-specific epidural simulator is presented using the developed body shape model, able to simulate needle insertion procedures on a 3D model of any patient size and shape. The developed ANN gave the most accurate results for body shape, size and ligament thickness. The

  16. [Body measurements of children and adolescents in Germany. Results of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS)].

    Science.gov (United States)

    Stolzenberg, H; Kahl, H; Bergmann, K E

    2007-01-01

    In the nationwide German Health Interview and Examination Survey for Children and Adolescents (KiGGS), a number of anthropometric parameters were assessed in a standardised way in 17,641 boys and girls. To this end, body weight and height, head circumference and upper arm length, as well as two skinfold thicknesses (triceps, subscapular) were measured for the entire age range (0-12 years); starting from 6 years of age, elbow breadth and from 11 years of age waist and hip circumference were measured in addition. For all parameters, means with confidence intervals are reported per age (in years) and gender. Median graphs depict the changes with increasing age according to gender for each body measurement. The complex age-related anthropometric developments along with significant gender specificity show the full range of the dynamic physical development in boys and girls. Based on skinfold measurement data, the body fat percentage was estimated. Thickness and location of the skinfolds, as well as the calculated waist-to-hip ratio is used as an indicator for gender-specific fat distribution. Using the frame index, it is attempted to estimate skeletal robustness. For the anthropometric parameters studied, hardly any regional differences were found. However, head circumference, frame index and all parameters strongly associated with body fat show a significant social status gradient. Children and adolescents with migration background have on average a lower height, larger waist circumference and higher percentage of body fat.

  17. Prevalence of lipodystrophy and metabolic abnormalities in HIV-infected African children after 3 years on first-line antiretroviral therapy.

    Science.gov (United States)

    Bwakura-Dangarembizi, Mutsawashe; Musiime, Victor; Szubert, Alexander J; Prendergast, Andrew J; Gomo, Zvenyika A; Thomason, Margaret J; Musarurwa, Cuthbert; Mugyenyi, Peter; Nahirya, Patricia; Kekitiinwa, Adeodata; Gibb, Diana M; Walker, Ann S; Nathoo, Kusum

    2015-02-01

    Most pediatric lipodystrophy data come from high-income/middle-income countries, but most HIV-infected children live in sub-Saharan Africa, where lipodystrophy studies have predominantly investigated stavudine-based regimens. Three years after antiretroviral therapy (ART) initiation, body circumferences and skinfold thicknesses were measured (n = 590), and fasted lipid profile assayed (n = 325), in children from 2 ARROW trial centres in Uganda/Zimbabwe. Analyses compared randomization to long-term versus short-term versus no zidovudine from ART initiation [unadjusted; latter 2 groups receiving abacavir+lamivudine+non-nucleoside-reverse-transciptase-inhibitor (nNRTI) long-term], and nonrandomized (confounder-adjusted) receipt of nevirapine versus efavirenz. Body circumferences and skinfold thicknesses were similar regardless of zidovudine exposure (P > 0.1), except for subscapular and supra-iliac skinfolds-for-age which were greater with long-term zidovudine (0.006 0.09; 0.02 lipodystrophy, providing reassurance where national programs now recommend long-term zidovudine. Efavirenz and nevirapine were also similar; however, the higher LDL observed with efavirenz and lower HDL observed with zidovudine suggests that zidovudine+lamivudine+efavirenz should be investigated in future.

  18. Effect of strength training and short-term detraining on muscle mass in women aged over 50 years old

    Directory of Open Access Journals (Sweden)

    Maryam Delshad

    2013-01-01

    Full Text Available Background: The loss of muscle mass is associated with aging. The aim of this study was to determine the effects of resistance training and detraining on muscle mass in elderly women. Methods: Twenty post-menopausal women aged ≥50 years old were enrolled. Matching for age, they were randomly assigned into control and resistance training group (RT. The intervention consisted of three sets of 10 repetitions for 10 movements with Thera-Band tubing (based on 80-100% 10-RM, three times a week, for 12 weeks and thereafter, four weeks detraining. Skinfold thickness was determined by caliper. Percentage of body fat was estimated from skinfold thickness (triceps and subscapular by McArdle method. Fat mass (FM and fat-free mass (FFM were calculated. Range of motion for trunk flexion and extension was determined. Results: During 12 weeks of intervention, significant increases were observed in 1-RM of biceps curl, FFM, trunk flexion and extension and significant decreases during four weeks detraining in RT group. The RT group demonstrated significant decreases during resistance training and increases during detraining in skinfold thickness. FFM, trunk flexion, and extension decreased and skinfold thickness, %FM, and weight of body fat increased in the control group (P < 0.05. Conclusions: Resistance training with Thera-Band enhanced strength and muscle endurance in elderly women and a 4-week detraining period had an adverse effect on muscle power. This suggests that a strength training program is an effective intervention to prevent functional reductions, and can contribute to improve neuromuscular function in older adults.

  19. Three Dimensional Photoelastic Investigations on Thick Rectangular ...

    African Journals Online (AJOL)

    Three different thicknesses to include the range of thin to moderately thick to thick plates are considered and it is shown that by employing a judicious slicing pattern stress variation at the critical sections of the plate can be obtained. Numerical results obtained are compared with those from a thin plate theory and a higher ...

  20. Macular thickness and volume in the elderly

    DEFF Research Database (Denmark)

    Subhi, Yousif; Forshaw, Thomas; Sørensen, Torben Lykke

    2016-01-01

    manifests in the macula of the elderly focusing on clinical relevant measures that are thicknesses and volumes of different macular areas. Ageing seems to increase center point foveal thickness. Ageing does not seem to change the center subfield thickness significantly. Ageing decreases the inner and outer...

  1. Thick Presentism and Newtonian Mechanics

    CERN Document Server

    Lubashevsky, Ihor

    2016-01-01

    In the present paper I argue that the formalism of Newtonian mechanics stems directly from the general principle to be called the principle of microlevel reducibility which physical systems obey in the realm of classical physics. This principle assumes, first, that all the properties of physical systems must be determined by their states at the current moment of time, in a slogan form it is "only the present matters to physics." Second, it postulates that any physical system is nothing but an ensemble of structureless particles arranged in some whose interaction obeys the superposition principle. I substantiate this statement and demonstrate directly how the formalism of differential equations, the notion of forces in Newtonian mechanics, the concept of phase space and initial conditions, the principle of least actions, etc. result from the principle of microlevel reducibility. The philosophical concept of thick presentism and the introduction of two dimensional time---physical time and meta-time that are mut...

  2. Creating universes with thick walls

    Science.gov (United States)

    Ulvestad, Andrew; Albrecht, Andreas

    2012-05-01

    We study the dynamics of a spherically symmetric false vacuum bubble embedded in a true vacuum region separated by a “thick wall”, which is generated by a scalar field in a quartic potential. We study the “Farhi-Guth-Guven” (FGG) quantum tunneling process by constructing numerical solutions relevant to this process. The Arnowitt-Deser-Misner mass of the spacetime is calculated, and we show that there is a lower bound that is a significant fraction of the scalar field mass. We argue that the zero mass solutions used to by some to argue against the physicality of the FGG process are artifacts of the thin wall approximation used in earlier work. We argue that the zero mass solutions should not be used to question the viability of the FGG process.

  3. Creating universes with thick walls

    CERN Document Server

    Ulvestad, Andrew

    2012-01-01

    We study the dynamics of a spherically symmetric false vacuum bubble embedded in a true vacuum region separated by a "thick wall", which is generated by a scalar field in a quartic potential. We study the "Farhi-Guth-Guven" (FGG) quantum tunneling process by constructing numerical solutions relevant to this process. The ADM mass of the spacetime is calculated, and we show that there is a lower bound that is a significant fraction of the scalar field mass. We argue that the zero mass solutions used to by some to argue against the physicality of the FGG process are artifacts of the thin wall approximation used in earlier work. We argue that the zero mass solutions should not be used to question the viability of the FGG process.

  4. Aerobic and anaerobic exercise capacities in obstructive sleep apnea and associations with subcutaneous fat distributions.

    Science.gov (United States)

    Ucok, Kagan; Aycicek, Abdullah; Sezer, Murat; Genc, Abdurrahman; Akkaya, Muzaffer; Caglar, Veli; Fidan, Fatma; Unlu, Mehmet

    2009-01-01

    Obesity is a strong risk factor for the development and progression of sleep apnea. Responses to exercise by patients with obstructive sleep apnea syndrome (OSAS) are clinically relevant to reducing body weight and cardiovascular risk factors. This study aimed to clarify the aerobic and anaerobic exercise capacities and their possible relationships with other findings in patients with OSAS. Forty patients (30 males, 10 females) and 40 controls (30 males, 10 females) were enrolled in this study. Questionnaires (excessive daytime sleepiness, daytime tiredness, morning headache, waking unrefreshed, and imbalance), overnight polysomnography, indirect laryngoscopy, and aerobic and anaerobic exercise tests were performed. Triceps, subscapular, abdomen, and thigh skinfold thicknesses were measured. Subcutaneous abdominal fat (abdomen skinfold) was significantly higher in OSAS patients than in controls. Maximal anaerobic power and anaerobic capacity were not different significantly between the patients and controls. We found that aerobic capacity was significantly lower in OSAS patients than in controls. Aerobic capacity was negatively correlated with upper-body subcutaneous fat (triceps and subscapular skinfolds) but not correlated with subcutaneous abdominal fat in OSAS patients. In multivariate analyses using all patients, the apnea-hypopnea index remained a significant independent predictor of aerobic capacity after controlling for a variety of potential confounders including body mass index. Our data confirm that central obesity (subcutaneous abdominal fat) is prominent in patients with OSAS. Our results suggest that lower aerobic exercise capacity in patients with OSAS might be due to daily physical activity that is restricted by OSA itself. This study also suggests that the degree of subcutaneous abdominal fat cannot be used for predicting aerobic capacity level. We think that upper-body subcutaneous fat might be suitable for determining the physical fitness of

  5. Is ovarian hyperstimulation associated with higher blood pressure in 4-year-old IVF offspring? Part II: an explorative causal inference approach.

    Science.gov (United States)

    La Bastide-Van Gemert, Sacha; Seggers, Jorien; Haadsma, Maaike L; Heineman, Maas Jan; Middelburg, Karin J; Roseboom, Tessa J; Schendelaar, Pamela; Hadders-Algra, Mijna; Van den Heuvel, Edwin R

    2014-03-01

    What causal relationships underlie the associations between ovarian stimulation, the IVF procedure, parental-, fertility- and child characteristics, and blood pressure (BP) and anthropometrics of 4-year-old IVF children? Causal models compatible with the data suggest the presence of positive direct effects of controlled ovarian hyperstimulation as applied in IVF (COH-IVF) on systolic blood pressure (SBP) percentiles and subscapular skinfold thickness. Increasing evidence suggests that IVF is associated with higher blood pressure and altered body fat distribution in offspring, but underlying mechanisms describing the causal relationships between the variables are largely unknown. In this assessor-blinded follow-up study, 194 children were assessed. The attrition rate until the 4-year-old assessment was 10%. We measured blood pressure and anthropometrics of 4-year-old singletons born following COH-IVF (n = 63), or born following modified natural cycle IVF (MNC-IVF, n = 52) or born to subfertile couples who conceived naturally (Sub-NC, n = 79). Primary outcome measures were the SBP and diastolic blood pressure (DBP) percentiles. Anthropometrics included triceps and subscapular skinfold thickness. Causal inference search algorithms and structural equation modeling were applied. Explorative analyses suggested a direct effect of COH on SBP percentiles and on subscapular skinfold thickness. This hypothesis needs confirmation with additional, preferably larger, studies. Search algorithms were used as explorative tools to generate hypotheses on the causal mechanisms underlying fertility treatment, blood pressure, anthropometrics and other variables. More studies using larger groups are needed to draw firm conclusions. Our findings are in line with other studies describing adverse effects of IVF on cardiometabolic outcome, but this is the first study suggesting a causal mechanism underlying this association. Perhaps ovarian hyperstimulation negatively influences

  6. Ontogenesis changes and sex dimorphism of subcutaneous fat distribution: 12-year longitudinal study of children and adolescents from Cracow, Poland.

    Science.gov (United States)

    Chrzanowska, Maria; Suder, Agnieszka

    2008-01-01

    The aim of the work was to analyze the direction and tempo of subcutaneous fat redistribution during ontogenesis, appearing sex differences and relations to puberty on the basis of 12-year longitudinal data of 270 boys and 154 girls from Cracow, Poland. They all had complete data (from 7 to 18-years old) of three trunk (subscapular, abdominal, suprailiac) and three extremity (triceps, knee, medial calf) skinfold thicknesses. The type of subcutaneous adipose tissue distribution was determined based on trunk to extremity ratio to analyze the process of fat redistribution. The analysis included medians of extremity and trunk skinfolds and medians of their sums and age altered frequency of central and peripheral type of fat distribution. To present empirical values, the median variability of the sums of three trunk and extremity skinfolds was calculated using a third degree polynomial as an age function. Polynomial regression of extremity skinfolds median explained 88% of its variability (F = 71.2, P < 0.001) and for trunk skinfolds as far as 96% (F = 111.65, P < 0.001). The median variability curves of both types of distribution crossed at the age of 11.88 in girls and 13.45 in boys directly preceding puberty stage, which indicated clear dependencies between fat redistribution and puberty. The results showed a tight connection between the process of subcutaneous fat redistribution and puberty, and also sex dimorphism of the process. More dynamic fat redistribution in boys contrasted trunk and extremity fatness, while in girls less dynamic changes resulted in more even fatness. Copyright 2008 Wiley-Liss, Inc.

  7. Correlations among adiposity measures in school-aged children

    Science.gov (United States)

    2013-01-01

    Background Given that it is not feasible to use dual x-ray absorptiometry (DXA) or other reference methods to measure adiposity in all pediatric clinical and research settings, it is important to identify reasonable alternatives. Therefore, we sought to determine the extent to which other adiposity measures were correlated with DXA fat mass in school-aged children. Methods In 1110 children aged 6.5-10.9 years in the pre-birth cohort Project Viva, we calculated Spearman correlation coefficients between DXA (n=875) and other adiposity measures including body mass index (BMI), skinfold thickness, circumferences, and bioimpedance. We also computed correlations between lean body mass measures. Results 50.0% of the children were female and 36.5% were non-white. Mean (SD) BMI was 17.2 (3.1) and total fat mass by DXA was 7.5 (3.9) kg. DXA total fat mass was highly correlated with BMI (rs=0.83), bioimpedance total fat (rs=0.87), and sum of skinfolds (rs=0.90), and DXA trunk fat was highly correlated with waist circumference (rs=0.79). Correlations of BMI with other adiposity indices were high, e.g., with waist circumference (rs=0.86) and sum of subscapular plus triceps skinfolds (rs=0.79). DXA fat-free mass and bioimpedance fat-free mass were highly correlated (rs=0.94). Conclusions In school-aged children, BMI, sum of skinfolds, and other adiposity measures were strongly correlated with DXA fat mass. Although these measurement methods have limitations, BMI and skinfolds are adequate surrogate measures of relative adiposity in children when DXA is not practical. PMID:23799991

  8. A Trial of the Ponderax Skinfold Caliper*

    African Journals Online (AJOL)

    laterally, at an angle of about 30· to vertical from the inferior angle of the scapula: In young women the sites of choice are triceps and supra-iliac, the latter being a vertical fold in the midaxillary line just .... Sloan, A. W. (1967): Ibid., 23. 311. . 4. Sloan, A. W., Burt, 1. J. and Blyth, C. S. (1962): Ibld., 17, 967. 5. Davidson, A. and.

  9. Anthropometrical Profile, Skinfold Tickness and Subcutaneous Fat ...

    African Journals Online (AJOL)

    Background: The threatening health problems resulting from excess subcutaneous fat depositions have been reported by the world Health Organization. Also noteworthy is that childhood obesity is a pointer to adult obesity. This necessitated a study on the anthropometrical profiles of adolescents of Southeast Nigeria using ...

  10. [Study on the thickness-change of different thickness thermoplastic materials after thermoforming and saliva immersion].

    Science.gov (United States)

    Zhang, Ning; Bai, Yu-Xing; Zhang, Kun-Ya; Ren, Chao-Chao; Zhou, Jie-Min; Qi, Peng

    2010-02-01

    To survey and compare the thickness-change of different thickness thermoplastic materials under different test condition and make sure the relationship between the thickness-change and the material initial thickness in order to provide a guide in selecting the suitable thickness thermoplastic in practice. To choose Biolon, the thickness include 1.0 mm, 0.75 mm, 0.5 mm. Used Electron Vernier caliper to measure the thickness-change of different thickness thermoplastic materials under different processing mode. The data was analyzed by SPSS 10.0. After thermoforming the thickness of thermoplastic became thinner, the thickness of Biolon 0.75 mm decreased by 0.14 mm, Biolon 1.0 mm decreased by 0.22 mm and Biolon 0.5 mm decreased by 0.14 mm. After saliva immersion the thickness became thicker. The thickness of Biolon 0.75 mm increased by 0.02 mm, Biolon 1.0 mm increased by 0.03 mm and Biolon 0.5 mm increased by 0.02 mm. 1)The influence of different processing mode to the thickness-change had relation to the material initial thickness. 2)The Biolon 0.75 mm had certain superiority in thickness stability compared to the homogeneous brand through the above research.

  11. A prospective study on obesity and subcutaneous fat patterning in relation to breast cancer in post-menopausal women participating in the DOM project.

    Science.gov (United States)

    den Tonkelaar, I.; Seidell, J. C.; Collette, H. J.; de Waard, F.

    1994-01-01

    The associations of body fat and body fat distribution with breast cancer risk were examined in a prospective study in 9,746 post-menopausal women with a natural menopause, aged 49-66 at intake, participating in a breast cancer screening project (the DOM project in Utrecht). During a follow-up period of 15 years (mean follow-up time 12.5 years) 260 women developed breast cancer. Fat distribution, assessed by contrasting groups of subcapsular and triceps skinfold thickness, was found to be unrelated to breast cancer incidence. No significant relationship between body fat, measured either by weight, Quetelet's index, triceps skinfold or subscapular skinfold, and breast cancer risk was found when analysed in quartiles. However, women in the upper decile compared with the lower decile of the distribution of Quetelet's index were found to have a 1.9 times (95% CI 1.1-3.3) higher risk for breast cancer. These results seemed to be in contrast with the significant positive association between fatness, analysed in quartiles, and breast cancer observed in a cross-sectional study, based on mammographic screening, carried out previously in the same population. Although the differences between the present, prospective, study and our cross-sectional study may be due to chance it may be that there are differences between characteristics of breast cancer detected at screening and subsequently, which influence the associations between measures of fatness and risk of breast cancer. PMID:8297734

  12. Maternal obesity influences the relationship between location of neonate fat mass and total fat mass.

    Science.gov (United States)

    Hull, H R; Thornton, J; Paley, C; Navder, K; Gallagher, D

    2015-08-01

    It is suggested that maternal obesity perpetuates offspring obesity to future generations. To determine whether location of neonate fat mass (FM: central vs. peripheral) is related to total neonate FM and whether maternal obesity influences this relationship. Neonate body composition and skin-fold thicknesses were assessed in healthy neonates (n = 371; 1-3 days old). Linear regression models examined the relationship between total FM and location of FM (central vs. peripheral). Location of FM was calculated by skin-folds: peripheral was the sum of (biceps and triceps)/2 and central was represented by the subscapular skin-fold. A significant interaction was found for location of FM and maternal obesity. Holding all predictors constant, in offspring born to non-obese mothers, a 0.5 mm increase in central FM predicted a 15 g greater total FM, whereas a 0.5 mm increase in peripheral FM predicted a 66 g greater total FM. However, in offspring born to obese mothers, a 0.5 mm increase in central FM predicted a 56 g total FM, whereas a 0.5 mm increase in peripheral FM predicted a 14 g greater total FM. The relationship between total FM and location of FM is influenced by maternal obesity. © 2014 The Authors. Pediatric Obesity © 2014 World Obesity.

  13. Autonomous Sea-Ice Thickness Survey

    Science.gov (United States)

    2016-06-01

    from the EM31 ............................................ 5 5 The Yeti-EM31 survey track plot. GPS track points (circles) were logged at 10 s...Using similar ice-temperature bins, Weale and Sodhi (2015) calculated the required ice thickness to support heavy tracked vehicles traversing...C is interpreted as the conductivity of an infinitely thick slab of sea ice. Ice thickness, Hice, is then obtained by subtracting the height of the

  14. The Effectiveness of Enteral Nutrition Support in the Growth of Children Patients with Cancer

    Directory of Open Access Journals (Sweden)

    Can Acipayam

    2014-12-01

    Full Text Available Aim: The purpose of this study was to assess, through anthropometric and biochemical parameters, the positive effect on growth of enteral nutrition support in children with cancer receiving chemotherapy. Material and Method: Forty-three consecutive patients newly diagnosed with pediatric malignant disease and receiving intensive chemotherapy were included. Twenty-six patients received an enteral nutrition formula. Seventeen control patients did not receive enteral nutrition formula. Anthropometric parameters (weight, height, body mass index, triceps, subscapular and suprailiac skinfold thickness, serum albumin, prealbumin and transferrin levels and lipid profiles were measured at time of diagnosis and the 3rd month. Results: At the end of 3 months we determined a marked increase in subscapular and suprailiac skin fold thicknesses in the enteral nutrition group compared to at time of diagnosis (p=0.01 and p=0.014, respectively. Prealbumin and albumin values increased considerably after 3 months of enteral nutrition formula support (p=0.005 and p=0.006, respectively. Weight percentile increment was determined (69.2% of patients in the enteral nutrition group compared to at time of diagnosis. At 3 months, albumin and suprailiac skinfold thicknesses values were higher in the enteral nutrition group as compared to controls (p=0.012 and p=0.017, respectively. There were no significant changes in anthropometric and biochemical parameters in the control group at the end of treatment compared to at time of diagnosis. Discussion: This study demonstrates an improvement in anthropometric and biochemical parameters in children with cancer receiving an enteral nutrition formula.

  15. Desenvolvimento de equação para estimativa da gordura corporal de mulheres idosas com osteoporose e osteopenia através da espessura de dobras cutâneas tendo como referência absorciometria por dupla emissão de raios X Desarrollo de una ecuación para estimar la grasa corporal de mujeres ancianas con osteoporosis y osteopenia a través de la espesura de dobleces cutáneas teniendo como referencia la absorciometría por doble emisión de rayos X Development of an equation for measurement of bodyfat mass of elderly women with osteoporosis or osteopenia through skin fold thickness using dual energy X-ray absorptiometry as a reference

    Directory of Open Access Journals (Sweden)

    TM Aniteli

    2006-12-01

    84 años, atendidas en Ambulatorio de Osteoporosis de la Disciplina de Reumatología de la Facultad de Medicina de la Universidad de San Pablo. Fueron medidas las espesuras de cuatro dobleces cutáneos (bíceps, tríceps, subescapular y suprailiaca y realizada la evaluación de la composición corporal por DXA. El análisis estadístico constó del test de Kolmogorov-Smirnov, el coeficiente de correlación de Pearson, el análisis de regresión lineal simple, el coeficiente de correlación intraclase, el test t de Student, el test de Bland-Altman y el cálculo del error total de la ecuación de acuerdo a Lohman (1992. RESULTADOS: El modelo de espesura de dobleces cutáneos que mejor explicó el porcentaje de grasa corporal incluyó la suma de los dobleces suprailiaco, bicipital y tricipital, determinando en hasta 72% el porcentaje de grasa corporal. Los valores medios de grasa corporal en kilogramos, estimados por los dobleces y medidos por el DXA, no fueron estadísticamente diferentes y estuvieron altamente correlacionados (r = 0,82; p INTRODUCTION AND OBJECTIVE: The body composition has been intensively investigated as a determinant of bone mineral density. The present study was developed in order to propose a predictive equation to calculate body fat percentage by means of skin folds thickness using bone densitometry (DXA as a reference in a group of elderly women with osteoporosis and osteopenia. METHODOLOGY: Twenty-nine women, mean age 67 to 84 years old, in attendance at the Osteoporosis Clinic at Rheumatology Division, School of Medicine, University of Sao Paulo, were evaluated. Four skin folds thickness were measured (biceps, triceps, subscapular and suprailiac and body composition by DXA was evaluated. The statistical analysis consisted of Kolmogorov-Smirnov test, Pearson's coefficient correlation, simple linear regression analysis, intra-class correlation coefficient, t Student test, Bland-Altman test and calculus of equation total error according to

  16. Estimating bark thicknesses of common Appalachian hardwoods

    Science.gov (United States)

    R. Edward Thomas; Neal D. Bennett

    2014-01-01

    Knowing the thickness of bark along the stem of a tree is critical to accurately estimate residue and, more importantly, estimate the volume of solid wood available. Determining the volume or weight of bark for a log is important because bark and wood mass are typically separated while processing logs, and accurate determination of volume is problematic. Bark thickness...

  17. ORIGINAL ARTICLE Sonographic gallbladder wall thickness in ...

    African Journals Online (AJOL)

    The study population's age ranged from 16 - 78 years, with a mean age and SD of 32±13.2 years. The age parameter was unevenly distributed. →. →. Fig. 1. Longitudinal US image showing site of measurement of gallbladder wall thickness (arrows). Table I. Age distribution of mean gallbladder wall thickness in the study ...

  18. Anthropometric differences among natives of Abuja living in urban and rural communities: correlations with other cardiovascular risk factors.

    Science.gov (United States)

    Adediran, Olufemi Sola; Adebayo, Philip Babatunde; Akintunde, Adeseye Abiodun

    2013-03-27

    There is an increase of obesity and other cardiovascular risk factors worldwide, but especially in developing countries where multifaceted transitions are occurring. There is need for more evidence for the cardio-metabolic effect of changing lifestyles and urbanization in Nigeria. This study aimed at defining rural-urban differences in anthropometric parameters in two Nigerian communities of the same ancestral origin and to determine the cardiovascular risk correlates of these anthropometric measurements. This was a cross-sectional epidemiological study using stratified cluster sampling method. We studied 335 and 332 urban and rural dwellers respectively. A complete cardiovascular profile as well as anthropometric measurements was compared between the two populations. All anthropometric indices considered in this study (weight, BMI, waist circumference, waist circumference/height ratio, abdominal height; biceps, triceps, sub-scapular, abdominal, superior iliac skinfold thicknesses) were significantly higher in urban than in the rural population (p = migration.

  19. Periodontal Biotype: Gingival Thickness as It Relates to Probe Visibility and Buccal Plate Thickness.

    Science.gov (United States)

    Frost, Natalie A; Mealey, Brian L; Jones, Archie A; Huynh-Ba, Guy

    2015-10-01

    Probe visibility is the clinical gold standard to discriminate thick from thin biotype but is prone to subjective interpretation. The primary objective of this study is to determine at what objective gingival thickness the probe becomes invisible through the tissue. A secondary objective is to compare mean buccal plate thickness between thick and thin biotypes as determined by probe visibility. Maxillary anterior teeth (n = 306) were studied in 56 human patients. Biotype was determined by probe visibility through the tissue. Gingival thickness was measured via transgingival sounding. Buccal plate thickness was measured (n = 66 teeth) by cone beam computed tomography. For the primary objective, the gingival thickness that best corresponded with probe invisibility was selected using the receiver operating characteristic and area under the curve (AUC) with the highest combination of sensitivity and specificity. For the secondary objective, mean buccal plate thickness was compared between sites in which the probe was visible and when it was not (Student t test, α= 0.05). The gingival thickness that most closely corresponded with probe invisibility was >0.8 mm (0.666 AUC, 67.7% sensitivity, 65.4% specificity). When the probe was visible, mean gingival thickness was 0.17 mm less (P biotype) and those in which it was not (i.e., thick biotype). Probe visibility was associated with thinner measurements of gingival thickness and showed a tendency to be associated with a thinner buccal plate.

  20. Peripapillary RNFL Thickness Changes after Panretinal Photocoagulation.

    Science.gov (United States)

    Yazdani, Shahin; Samadi, Poorya; Pakravan, Mohammad; Esfandiari, Hamed; Ghahari, Elham; Nourinia, Ramin

    2016-09-01

    To evaluate changes in peripapillary retinal nerve fiber layer (RNFL) thickness as determined by spectral domain optical coherence tomography (SD-OCT) after panretinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR). Forty-two eyes of 42 diabetic patients who were scheduled for PRP were enrolled in this interventional case series. Peripapillary RNFL thickness was measured using SD-OCT (OCT 1000; Topcon Co., Tokyo, Japan) at baseline and 1, 3, and 6 months after PRP. Mean global RNFL thickness was increased significantly by 3 μm (p = 0.04) 1 month after PRP and was then decreased marginally significantly by 2.4 μm at 6 months (p = 0.054) as compared to baseline values. After 1 month, RNFL thickness was increased in all quadrants, but only changes in the temporal quadrant were significant (p = 0.009). At 6 months, progressive RNFL thinning occurred in all quadrants; however, only changes in the superior quadrant were significant (p = 0.041). Visual acuity was improved by an average of 0.02 logMAR after 6 months, but this change was not statistically significant. Shortly after PRP, RNFL thickness (as determined by SD-OCT) increases, but a decrease in RNFL thickness occurs at 6 months post-PRP. RNFL thickness changes based on OCT should be interpreted with caution in diabetic eyes undergoing PRP.

  1. Translucency of dental ceramics with different thicknesses.

    Science.gov (United States)

    Wang, Fu; Takahashi, Hidekazu; Iwasaki, Naohiko

    2013-07-01

    The increased use of esthetic restorations requires an improved understanding of the translucent characteristics of ceramic materials. Ceramic translucency has been considered to be dependent on composition and thickness, but less information is available about the translucent characteristics of these materials, especially at different thicknesses. The purpose of this study was to investigate the relationship between translucency and the thickness of different dental ceramics. Six disk-shaped specimens of 8 glass ceramics (IPS e.max Press HO, MO, LT, HT, IPS e.max CAD LT, MO, AvanteZ Dentin, and Trans) and 5 specimens of 5 zirconia ceramics (Cercon Base, Zenotec Zr Bridge, Lava Standard, Lava Standard FS3, and Lava Plus High Translucency) were prepared following the manufacturers' instructions and ground to a predetermined thickness with a grinding machine. A spectrophotometer was used to measure the translucency parameters (TP) of the glass ceramics, which ranged from 2.0 to 0.6 mm, and of the zirconia ceramics, which ranged from 1.0 to 0.4 mm. The relationship between the thickness and TP of each material was evaluated using a regression analysis (α=.05). The TP values of the glass ceramics ranged from 2.2 to 25.3 and the zirconia ceramics from 5.5 to 15.1. There was an increase in the TP with a decrease in thickness, but the amount of change was material dependent. An exponential relationship with statistical significance (Pceramics and zirconia ceramics. The translucency of dental ceramics was significantly influenced by both material and thickness. The translucency of all materials increased exponentially as the thickness decreased. All of the zirconia ceramics evaluated in the present study showed some degree of translucency, which was less sensitive to thickness compared to that of the glass ceramics. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  2. Mechanical Properties of Additively Manufactured Thick Honeycombs

    Science.gov (United States)

    Hedayati, Reza; Sadighi, Mojtaba; Mohammadi Aghdam, Mohammad; Zadpoor, Amir Abbas

    2016-01-01

    Honeycombs resemble the structure of a number of natural and biological materials such as cancellous bone, wood, and cork. Thick honeycomb could be also used for energy absorption applications. Moreover, studying the mechanical behavior of honeycombs under in-plane loading could help understanding the mechanical behavior of more complex 3D tessellated structures such as porous biomaterials. In this paper, we study the mechanical behavior of thick honeycombs made using additive manufacturing techniques that allow for fabrication of honeycombs with arbitrary and precisely controlled thickness. Thick honeycombs with different wall thicknesses were produced from polylactic acid (PLA) using fused deposition modelling, i.e., an additive manufacturing technique. The samples were mechanically tested in-plane under compression to determine their mechanical properties. We also obtained exact analytical solutions for the stiffness matrix of thick hexagonal honeycombs using both Euler-Bernoulli and Timoshenko beam theories. The stiffness matrix was then used to derive analytical relationships that describe the elastic modulus, yield stress, and Poisson’s ratio of thick honeycombs. Finite element models were also built for computational analysis of the mechanical behavior of thick honeycombs under compression. The mechanical properties obtained using our analytical relationships were compared with experimental observations and computational results as well as with analytical solutions available in the literature. It was found that the analytical solutions presented here are in good agreement with experimental and computational results even for very thick honeycombs, whereas the analytical solutions available in the literature show a large deviation from experimental observation, computational results, and our analytical solutions. PMID:28773735

  3. Turbine airfoil with outer wall thickness indicators

    Science.gov (United States)

    Marra, John J; James, Allister W; Merrill, Gary B

    2013-08-06

    A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

  4. Film thickness determination by grazing incidence diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Battiston, G. A.; Gerbasi, R. [CNR, Padua (Italy). Istituto di Chimica e Tecnologie Inorganiche e dei Materiali Avanzati

    1996-09-01

    Thin films deposited via MOCVD (Metal Organic Chemical Vapour Deposition) are layers in the thickness range of a few manometers to about ten micrometers. An understanding of the physics and chemistry of films is necessary for a better comprehension of the phenomena involved in the film deposition procedure and its optimisation. Together with the crystalline phase a parameter that must be determined is the thickness of the layer. In this work the authors present a method for the measurement of the film thickness. This procedure, based on diffraction intensity absorption of the X-rays, both incident and diffracted in passing through the layers, resulted quite simple, rapid and non-destructive.

  5. A database of worldwide glacier thickness observations

    DEFF Research Database (Denmark)

    Gärtner-Roer, I.; Naegeli, K.; Huss, M.

    2014-01-01

    surface observations. However, although thickness has been observed on many glaciers and ice caps around the globe, it has not yet been published in the shape of a readily available database. Here, we present a standardized database of glacier thickness observations compiled by an extensive literature...... review and from airborne data extracted from NASA's Operation IceBridge. This database contains ice thickness observations from roughly 1100 glaciers and ice caps including 550 glacier-wide estimates and 750,000 point observations. A comparison of these observational ice thicknesses with results from...... area- and slope-dependent approaches reveals large deviations both from the observations and between different estimation approaches. For glaciers and ice caps all estimation approaches show a tendency to overestimation. For glaciers the median relative absolute deviation lies around 30% when analyzing...

  6. Greenland Radar Ice Sheet Thickness Measurements

    Data.gov (United States)

    National Aeronautics and Space Administration — Two 150-MHz coherent radar depth sounders were developed and flown over the Greenland ice sheet to obtain ice thickness measurements in support of PARCA...

  7. Russian River Ice Thickness and Duration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of river ice thickness measurements, and beginning and ending dates for river freeze-up events from fifty stations in northern Russia. The...

  8. Wilcox Group Apparent Thickness, Gulf Coast (wlcxthkg)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Apparent Wilcox Group thickness maps are contoured from location and top information derived from the Petroleum Information (PI) Wells database. The Wilcox...

  9. Saturated thickness, High Plains aquifer, 2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This raster data set represents the saturated thickness of the High Plains aquifer of the United States, 2009, in feet. The High Plains aquifer underlies...

  10. Arctic Sea Ice Freeboard and Thickness

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides measurements of sea ice freeboard and sea ice thickness for the Arctic region. The data were derived from measurements made by from the Ice,...

  11. Heritability of Choroidal Thickness in the Amish.

    Science.gov (United States)

    Sardell, Rebecca J; Nittala, Muneeswar G; Adams, Larry D; Laux, Reneé A; Cooke Bailey, Jessica N; Fuzzell, Denise; Fuzzell, Sarada; Reinhart-Mercer, Lori; Caywood, Laura J; Horst, Violet; Mackay, Tine; Dana, Debbie; Sadda, SriniVas R; Scott, William K; Stambolian, Dwight; Haines, Jonathan L; Pericak-Vance, Margaret A

    2016-12-01

    To evaluate the heritability of choroidal thickness and its relationship to age-related macular degeneration (AMD). Cohort study. Six hundred eighty-nine individuals from Amish families with early or intermediate AMD. Ocular coherence tomography was used to quantify choroidal thickness, and fundus photography was used to classify eyes into categories using a modified Clinical Age-Related Maculopathy Staging (CARMS) system. Repeatability and heritability of choroidal thickness and its phenotypic and genetic correlations with the AMD phenotype (CARMS category) were estimated using a generalized linear mixed model (GLMM) approach that accounted for relatedness, repeated measures (left and right eyes), and the effects of age, gender, and refraction. Heritability of choroidal thickness and its phenotypic and genetic correlation with the AMD phenotype (CARMS category). Phenotypic correlation between choroidal thickness and CARMS category was moderate (Spearman's rank correlation, rs = -0.24; n = 1313 eyes) and significant (GLMM posterior mean, -4.27; 95% credible interval [CI], -7.88 to -0.79; P = 0.02) after controlling for relatedness, age, gender, and refraction. Eyes with advanced AMD had thinner choroids than eyes without AMD (posterior mean, -73.8; 95% CI, -94.7 to -54.6; P < 0.001; n = 1178 eyes). Choroidal thickness was highly repeatable within individuals (repeatability, 0.78; 95% CI, 0.68 to 0.89) and moderately heritable (heritability, 0.40; 95% CI, 0.14 to 0.51), but did not show significant genetic correlation with CARMS category, although the effect size was moderate (genetic correlation, -0.18; 95% CI, -0.49 to 0.16). Choroidal thickness also varied with age, gender, and refraction. The CARMS category showed moderate heritability (heritability, 0.49; 95% CI, 0.26 to 0.72). We quantify the heritability of choroidal thickness for the first time, highlighting a heritable, quantitative trait that is measurable in all individuals regardless of AMD

  12. LMC Microlensing and Very Thick Disks

    OpenAIRE

    Gyuk, Geza; Gates, Evalyn

    1998-01-01

    We investigate the implications of a very thick (scale height 1.5 - 3.0 kpc) disk population of MACHOs. Such a population represents a reasonable alternative to standard halo configurations of a lensing population. We find that very thick disk distributions can lower the lens mass estimate derived from the microlensing data toward the LMC, although an average lens mass substantially below $0.3\\Msol$ is unlikely. Constraints from direct searches for such lenses imply very low luminosity object...

  13. Thick Film Temperature Sensors Using Standard Pastes

    OpenAIRE

    Janoska, I.; Haskard, M. R.

    1986-01-01

    Standard thick film resistor pastes exhibit changes in their electrical characteristics when printed on top of dielectric layers. Of particular interest is the inherent change in their temperature coefficient of resistance. Simple temperature sensors were formed by deliberately printing thick film resistor pastes on top of larger area dielectric layers. Temperature tests carried out on these devices have shown that by selecting the correct paste combination and resistor aspect ratio ...

  14. Thin wideband absorber with optimal thickness

    OpenAIRE

    Kazemzadeh, Alireza

    2010-01-01

    The known methods for designing nonmagnetic absorbers usually aim for either the reduction of total thickness or increase of absorption bandwidth by sacrificing the other parameter. The conventional circuit analog absorbers aim for large bandwidths whereas the newly proposed meta-material or optimized geometry designs try to reduce the thickness of the absorber. By the aid of the capacitive circuit absorber approach, an optimal method for designing thin absorbers with practical bandwidths is...

  15. Testing and analysis of ultra thick composites

    OpenAIRE

    Zimmermann, Kristian; Zenkert, Dan; Siemetzki, M.

    2010-01-01

    For the development of a composite main landing gear fitting in carbon fiber reinforced plastics the behavior and performance of Ultra Thick Laminate components is investigated. Material thicknesses exceeds 60 mm. For the purpose of validation a test program is arranged using T-cross sections subjected to multiple load cases. The components are manufactured entirely with non crimped fabrics (NCF) using an adapted open mould manufacturing process. In addition to these T-Sections large full sca...

  16. Sampling supraglacial debris thickness using terrestrial photogrammetry

    Science.gov (United States)

    Nicholson, Lindsey; Mertes, Jordan

    2017-04-01

    The melt rate of debris-covered ice differs to that of clean ice primarily as a function of debris thickness. The spatial distribution of supraglacial debris thickness must therefore be known in order to understand how it is likely to impact glacier behaviour, and meltwater contribution to local hydrological resources and global sea level rise. However, practical means of determining debris cover thickness remain elusive. In this study we explore the utility of terrestrial photogrammetry to produce high resolution, scaled and texturized digital terrain models of debris cover exposures above ice cliffs as a means of quantifying and characterizing debris thickness. Two Nikon D5000 DSLRs with Tamron 100mm lenses were used to photograph a sample area of the Ngozumpa glacier in the Khumbu Himal of Nepal in April 2016. A Structure from Motion workflow using Agisoft Photoscan software was used to generate a surface models with manual point measurements along the same clifftops. We conclude that sufficiently high resolution photogrammetry, with precise scaling information, provides a useful means to determine debris thickness at clifftop exposures. The resolution of the possible measurements depends on image resolution, the accuracy of the ground control points and the computational capacity to generate centimetre scale surface models. Application of such techniques to sufficiently high resolution imagery from UAV-borne cameras may offer a powerful means of determining debris thickness distribution patterns over debris covered glacier termini.

  17. Thickness filters for gradient based multi-material and thickness optimization of laminated composite structures

    DEFF Research Database (Denmark)

    Sørensen, Rene; Lund, Erik

    2015-01-01

    This paper presents a new gradient based method for performing discrete material and thickness optimization of laminated composite structures. The novelty in the new method lies in the application of so-called casting constraints, or thickness filters in this context, to control the thickness...... variation throughout the laminate. The filters replace the layerwise density variables with a single continuous through-the-thickness design variable. Consequently, the filters eliminate the need for having explicit constraints for preventing intermediate void through the thickness of the laminate....... Therefore, the filters reduce both the number of constraints and design variables in the optimization problem. Based upon a continuous approximation of a unit step function, the thickness filters are capable of projecting discrete 0/1 values to the underlying layerwise or ”physical” density variables which...

  18. Snow thickness retrieval over thick Arctic sea ice using SMOS satellite data

    Directory of Open Access Journals (Sweden)

    N. Maaß

    2013-12-01

    Full Text Available The microwave interferometric radiometer of the European Space Agency's Soil Moisture and Ocean Salinity (SMOS mission measures at a frequency of 1.4 GHz in the L-band. In contrast to other microwave satellites, low frequency measurements in L-band have a large penetration depth in sea ice and thus contain information on the ice thickness. Previous ice thickness retrievals have neglected a snow layer on top of the ice. Here, we implement a snow layer in our emission model and investigate how snow influences L-band brightness temperatures and whether it is possible to retrieve snow thickness over thick Arctic sea ice from SMOS data. We find that the brightness temperatures above snow-covered sea ice are higher than above bare sea ice and that horizontal polarisation is more affected by the snow layer than vertical polarisation. In accordance with our theoretical investigations, the root mean square deviation between simulated and observed horizontally polarised brightness temperatures decreases from 20.9 K to 4.7 K, when we include the snow layer in the simulations. Although dry snow is almost transparent in L-band, we find brightness temperatures to increase with increasing snow thickness under cold Arctic conditions. The brightness temperatures' dependence on snow thickness can be explained by the thermal insulation of snow and its dependence on the snow layer thickness. This temperature effect allows us to retrieve snow thickness over thick sea ice. For the best simulation scenario and snow thicknesses up to 35 cm, the average snow thickness retrieved from horizontally polarised SMOS brightness temperatures agrees within 0.1 cm with the average snow thickness measured during the IceBridge flight campaign in the Arctic in spring 2012. The corresponding root mean square deviation is 5.5 cm, and the coefficient of determination is r2 = 0.58.

  19. Minimization of wave drag due to thickness with constraints on constant volume and maximum thickness position

    OpenAIRE

    Ishida, Yoji; 石田 洋治

    2001-01-01

    A numerical method has been developed for designing minimum-drag supersonic wing thickness with constraints on total volume and wing's maximum thickness position. This method is based on the linearized supersonic theory and is an extension of Kawasaki's method (ref.10) which deals only with total volume constraint. The maximum thickness position of the wing, a new constraint condition, is important information from both aerodynamic and structural points of view. The addition of the constraint...

  20. An Experimental Study on Wall Thickness Distribution in Thermoforming

    Directory of Open Access Journals (Sweden)

    Sencer Süreyya Karabeyoglu

    2017-09-01

    Full Text Available In this work, Polystyrene (PS sheets were thermoformed in predetermined conditions. Wall thickness distributions obtained by experimental method in PS thermoformed products. Then same thickness distributions were predicted by using Geometric Element Analysis (GEA. The thickness results which obtained experimentally, compared to thickness distributions which were predicted by GEA. It has been found that GEA does not reveal thickness distributions precisely.

  1. Minimization of Wave Drag Due to Thickness with Constraints on Constant Volume and Maximum Thickness Position

    Science.gov (United States)

    Ishida, Yoji

    We have developed a numerical method for design of minimum-drag supersonic wing thickness with constraints on total volume and wing maximum thickness position. The method is based on the linearized supersonic theory and is an extension of Kawasaki's method which deals only with total volume constraint. The maximum thickness position of the wing, a new constraint condition, is an important information from both aerodynamic and structural point of view. The addition of the constraint has considerably extended the design possibility and has actually produced many interesting optimum thickness families. Numerical examples are given for delta, gothic and arrow wings which confirm the usefulness of present design method.

  2. Thickness quantization in a reorientation transition

    Science.gov (United States)

    Venus, David; He, Gengming; Winch, Harrison; Belanger, Randy

    The reorientation transition of an ultrathin film from perpendicular to in-plane magnetization is driven by a competition between shape and surface anisotropy. It is accompanied by a ''stripe'' domain structure that evolves as the reorientation progresses. Often, an n layer film has stable perpendicular magnetization and an n+1 layer film has stable in-plane magnetization. If the domain walls are not pinned, the long-range stripe domain pattern averages over this structure so that the transition occurs at a non-integer layer thickness. We report in situ experimental measurements of the magnetic susceptibility (via MOKE) of the reorientation transition in Fe/2 ML Ni/W(110) films as a function of thickness as they are deposited at room temperature. In addition to a peak at the reorientation transition, we observe a strong precursor due to thickness quantization in atomic layers. This peak is described quantitatively by the response of small islands of thickness 3 layers with in-plane anisotropy in a sea of 2 layers Fe with perpendicular anisotropy. The fitted parameters give an estimate of the island size at which the response disappears. This size corresponds to a domain wall thickness, so that the islands become locally in-plane, demonstrating the self-consistency of the model.

  3. Anthropometric measurements in childhood and prediction of cardiovascular risk factors in adulthood: Kaunas cardiovascular risk cohort study.

    Science.gov (United States)

    Petkeviciene, Janina; Klumbiene, Jurate; Kriaucioniene, Vilma; Raskiliene, Asta; Sakyte, Edita; Ceponiene, Indre

    2015-03-04

    This study aimed to examine the associations between anthropometric measurements in childhood and adulthood as well as the effect of childhood body mass index (BMI) and skinfold thickness in the prediction of adult cardiovascular risk factors. The Study subjects were participants of the Kaunas Cardiovascular Risk Cohort study. They were 12-13 years old at the time of the baseline survey (1977) and 48-49 years old in the 35-year follow-up survey (2012, n = 506). In childhood, height, weight, subscapular and triceps skinfold thickness measurements were taken. In 2012, health examination involved measurements of blood pressure (BP), BMI, waist circumference, glucose, lipids, and high-sensitivity C-reactive protein (CRP) levels. Logistic regression models were fitted to assess the associations of childhood BMI and skinfold thicknesses as well as BMI gain with cardiovascular risk factors in middle age. All logistic regression models were adjusted for sex, physical activity level, alcohol consumption, smoking and family history of obesity. Over 35 years of follow-up, BMI gain was greater in men than in women. Anthropometric measurements in childhood significantly correlated with values measured in adulthood. The highest correlation coefficients were defined for weight and BMI measurements (in girls r = 0.56 and r = 0.51 respectively; in boys r = 0.45 and r = 0.41 respectively, P risk of adult obesity, metabolic syndrome, hyperglycaemia or type 2 diabetes, and elevated level of high-sensitivity CRP increased with a rise in childhood BMI and skinfold thicknesses, irrespectively of BMI gain from childhood to adulthood. No relationship was found between childhood anthropometric measurements and arterial hypertension, raised level of triglycerides or reduced level of HDL cholesterol. Gain in BMI from childhood to adulthood was associated with increased odds of all above-mentioned risk factors independently of childhood BMI. Risk of metabolic syndrome

  4. The Appropriateness of the Length of Insulin Needles Based on Determination of Skin and Subcutaneous Fat Thickness in the Abdomen and Upper Arm in Patients with Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Kang Hee Sim

    2014-04-01

    Full Text Available BackgroundLonger needle and complicated insulin injection technique such as injecting at a 45-degree angle and making skinfolds may decrease patient compliance to insulin injection therapy. In this light, shorter insulin needles have been recently developed. However, it is necessary to ascertain that such shorter needles are appropriate for Korean patients with diabetes as well.MethodsFirst, the diverse demographic and diabetic features of 156 Korean adults with diabetes were collected by a questionnaire and a device unit of body fat measurement. The skin and subcutaneous fat thicknesses of each subject were measured by Ultrasound device with a 7- to 12-MHz probe. Data were analyzed using analysis of variance and multiple linear regression.ResultsThe mean skin thickness was 2.29±0.37 mm in the abdomen and 2.00±0.34 mm in the upper arms, and the mean subcutaneous fat thickness was to 10.15±6.54 mm in the abdomen and 5.50±2.68 mm in the upper arms. Our analysis showed that the factors affecting the skin thickness of the abdomen and upper arms were gender and body mass index (BMI, whereas the factors influencing the subcutaneous fat thickness in the abdomen were gender and BMI, and the factors influencing the subcutaneous fat thickness in the upper arms were gender, BMI, and age. Insulin fluids may not appear to be intradermally injected into the abdomen and upper arms at any needle lengths. The risk of intramuscular injection is likely to increase with longer insulin needles and lower BMI.ConclusionIt is recommended to fully inform the patients about the lengths of needles for insulin injections. As for the recommended needle length, the findings of this study indicate that needles as short as 4 mm are sufficient to deliver insulin for Korean patients with diabetes.

  5. Is urolithiasis in children associated with obesity or malnutrition?

    Science.gov (United States)

    Selimoğlu, Mukadder Ayşe; Menekşe, Engin; Tabel, Yılmaz

    2013-03-01

    Although it is known that obesity predisposes to urolithiasis, a tendency for malnutrition in children with urolithiasis owing to recurrent urinary infections and abdominal pain also makes sense. In this study, we aimed to determine the nutritional status of infants and children with urolithiasis, and to observe whether obesity or malnutrition is more prevalent in that population. One hundred eighty-seven children aged 4 months to 17 years (mean, 4.9 ± 4.4 years) with urolithiasis, and 278 age- and sex-matched children without any chronic diseases were included. Anthropometric evaluations, including weight and height standard deviation score (SDS), body mass index, and triceps and subscapular skinfold thickness (SFT), were performed. Mean weight SDSs of the patients was statistically lower than that of the control subjects (P Malnutrition rate was statistically higher in the patients with urolithiasis when evaluated according to weight SDS and percentiles of body mass index and SFT. When the age factor was taken into account, the percentage of malnutrition, determined by the percentiles of triceps and subscapular SFT measurements, was found to be higher in children younger than 2 years. Short stature was more prevalent in older children. Malnutrition among children with urolithiasis is not as rare as thought previously. A careful anthropometric evaluation should be included in the clinical assessment of those children. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  6. Patterns of body size and adiposity among UK children of South Asian, black African-Caribbean and white European origin: Child Heart And health Study in England (CHASE Study).

    Science.gov (United States)

    Nightingale, Claire M; Rudnicka, Alicja R; Owen, Chris G; Cook, Derek G; Whincup, Peter H

    2011-02-01

    The objective of this study was to examine adiposity patterns in UK South Asian, black African-Caribbean and white European children using a range of adiposity markers. A cross-sectional survey in London, Birmingham and Leicester primary schools was conducted. Weight, height, waist circumference, skinfold thickness values (biceps, triceps, subscapular and suprailiac) were measured. Fat mass was derived from bioimpedance; optimally height-standardized indices were derived for all adiposity markers. Ethnic origin was based on parental self-report. Multilevel models were used to obtain adjusted means and ethnic differences adjusted for gender, age, month, observer and school (fitted as a random effect). A total of 5887 children aged 9-10 years participated (response rate 68%), including 1345 white Europeans, 1523 South Asians and 1570 black African-Caribbeans. Compared with white Europeans, South Asians had a higher sum of all skinfolds and fat mass percentage, and their body mass index (BMI) was lower. South Asians were slightly shorter but use of optimally height-standardized indices did not materially affect these comparisons. At any given fat mass, BMI was lower in South Asians than white Europeans. In similar comparisons, black African-Caribbeans had a lower sum of all skinfolds but a higher fat mass percentage, and their BMI was higher. Black African-Caribbeans were markedly taller. Use of optimally height-standardized indices yielded markedly different findings; sum of skinfolds index was markedly lower, whereas fat mass index and weight-for-height index were similar. At any given fat mass, BMI was similar in black African-Caribbeans and white Europeans. UK South Asian children have higher adiposity levels and black African-Caribbeans have similar or lower adiposity levels when compared with white Europeans. However, these differences are not well represented by comparisons based on BMI, which systematically underestimates adiposity in South Asians, and in

  7. Patterns of body size and adiposity among UK children of South Asian, black African–Caribbean and white European origin: Child Heart And health Study in England (CHASE Study)

    Science.gov (United States)

    Nightingale, Claire M; Rudnicka, Alicja R; Owen, Chris G; Cook, Derek G; Whincup, Peter H

    2011-01-01

    Background The objective of this study was to examine adiposity patterns in UK South Asian, black African–Caribbean and white European children using a range of adiposity markers. A cross-sectional survey in London, Birmingham and Leicester primary schools was conducted. Weight, height, waist circumference, skinfold thickness values (biceps, triceps, subscapular and suprailiac) were measured. Fat mass was derived from bioimpedance; optimally height-standardized indices were derived for all adiposity markers. Ethnic origin was based on parental self-report. Multilevel models were used to obtain adjusted means and ethnic differences adjusted for gender, age, month, observer and school (fitted as a random effect). A total of 5887 children aged 9–10 years participated (response rate 68%), including 1345 white Europeans, 1523 South Asians and 1570 black African–Caribbeans. Results Compared with white Europeans, South Asians had a higher sum of all skinfolds and fat mass percentage, and their body mass index (BMI) was lower. South Asians were slightly shorter but use of optimally height-standardized indices did not materially affect these comparisons. At any given fat mass, BMI was lower in South Asians than white Europeans. In similar comparisons, black African–Caribbeans had a lower sum of all skinfolds but a higher fat mass percentage, and their BMI was higher. Black African–Caribbeans were markedly taller. Use of optimally height-standardized indices yielded markedly different findings; sum of skinfolds index was markedly lower, whereas fat mass index and weight-for-height index were similar. At any given fat mass, BMI was similar in black African–Caribbeans and white Europeans. Conclusions UK South Asian children have higher adiposity levels and black African–Caribbeans have similar or lower adiposity levels when compared with white Europeans. However, these differences are not well represented by comparisons based on BMI, which systematically

  8. Theory of the sea ice thickness distribution

    CERN Document Server

    Toppaladoddi, Srikanth

    2015-01-01

    We use concepts from statistical physics to transform the original evolution equation for the sea ice thickness distribution $g(h)$ due to Thorndike et al., (1975) into a Fokker-Planck like conservation law. The steady solution is $g(h) = {\\cal N}(q) h^q \\mathrm{e}^{-~ h/H}$, where $q$ and $H$ are expressible in terms of moments over the transition probabilities between thickness categories. The solution exhibits the functional form used in observational fits and shows that for $h \\ll 1$, $g(h)$ is controlled by both thermodynamics and mechanics, whereas for $h \\gg 1$ only mechanics controls $g(h)$. Finally, we derive the underlying Langevin equation governing the dynamics of the ice thickness $h$, from which we predict the observed $g(h)$. The genericity of our approach provides a framework for studying the geophysical scale structure of the ice pack using methods of broad relevance in statistical mechanics.

  9. Thickness dependent properties of magnetic ultrathin films

    Energy Technology Data Exchange (ETDEWEB)

    Cong, Bach Thanh [Faculty of Physics, Hanoi University of Science, VNU, 334 Nguyen Trai, Hanoi (Viet Nam); Thao, Pham Huong, E-mail: hthao82@gmail.com [Faculty of Physics, Hanoi University of Science, VNU, 334 Nguyen Trai, Hanoi (Viet Nam); Faculty of Physics, Hue College of Education, 32 Le Loi, Thua Thien Hue (Viet Nam)

    2013-10-01

    The dependence of magnetic properties on the thickness of few-layer thin films is investigated at finite temperature using the functional integral method for solving the Heisenberg spin model. The temperature dependence of the ultra-thin film's magnetization and Curie temperature are calculated in terms of the mean field theory and of the Gaussian spin fluctuation approximations. It has been shown that both Curie temperature and temperature interval, where the magnetization is non-zero, are strongly reduced with the thickness reduction by using the spin fluctuation approximations in comparison with the mean field results. Curie temperature dependence on the film thickness calculated numerically well agrees with the experimental data for Ni/Cu(1 0 0) and Ni/Cu(1 1 1) ultrathin films.

  10. Estimating the thickness of sea ice

    Science.gov (United States)

    Bourke, Robert H.; Paquette, Robert G.

    1989-01-01

    Sea ice freeboard, thickness, and snow depth were measured from a series of closely spaced (5 to 10 m) drill hole sites from five free-floating multiyear ice floes in the Beaufort Sea during the spring of 1986 and 1987. A regression of ice thickness on ice draft was performed on the data from each floe and for the combined data set. Regressions were performed both on nonscreened data and data screened to eliminate pressure ridges. A predictive equation was developed permitting the total ice thickness to be estimated from measured values of ice draft, e.g., from submarine echo sounder traces: t = 1.115 d. The keel-sail height ratio for pressure ridges was found constant at 3.3 to 1, in agreement with past observations.

  11. Dust measurement in thick seam mining

    Energy Technology Data Exchange (ETDEWEB)

    Gillies, A.D.S.; Wu, H.W. [University of Queensland, Brisbane, Qld. (Australia)

    2001-12-01

    An Australian Coal Association Research Program (ACARP) funded scoping study was undertaken to examine dust problems being faced by Australian thick seam longwall mine operators, evaluate options and recommended priorities for improvement. The study involved a number of stages. A detailed survey of six Australian thick seam mine operators was undertaken to identify individual mine issues. A comprehensive literature review on Australian and foreign developments, with emphasis on publications from the last ten years, was undertaken. Views and advice from recognised dust experts both within Australia and overseas were sought. Some approaches to assessment of dust compliance and analysis of trends exhibited were undertaken; and both analysis and evaluation were undertaken on some options for improvement. This paper describes results from the questionnaire survey and presents some potential thick seam longwall dust issue based on the analysis of dust survey results from both published US data and from Joint Coal Board (JCB) data. 3 figs., 3 tabs.

  12. Effect of thickness on airfoil surface noise

    Science.gov (United States)

    Olsen, W.; Wagner, J.

    1982-01-01

    Noise emission from very small chord and very large chord airfoils was measured with eleven 0.63 cm microphones placed along a horizontal semicircle (4.57 m radius) that was centered at the leading edge of the test airfoil. The noise signals were analyzed by an automated spectrum analyzer which yielded 1/3-octave band sound pressure level spectra for each microphone, and the data were corrected to remove the effects of atmospheric attenuation and jet noise. It is found that the effect of thickness is large and must be accounted for in any fundamental airfoil noise theory that attempts to describe the noise emitted from real airfoils. Incident mean velocity gradients and compressibility must also be taken into account. The effect of thickness increases with frequency, with thick airfoils being quieter than thin ones.

  13. [Preliminary investigation of effect of serum leptin on nutritional state of COPD patients].

    Science.gov (United States)

    Yuan, Y; Wang, Z; Liu, C

    2000-05-01

    To explore the significance of serum leptin and TNF-alpha in malnutrition of COPD. Serum leptin and TNF-alpha concentrations were measured by radioimmunoassay. Body mass index (BMI), percent normal body weight (NW%), triceps skin-fold thickness (TSF), subscapular skin-fold thickness (SSF), mid-upper arm circumference (MAC), serum albumin (ALB) and total lymphocytes count (LYM) were determined in 31 patients with COPD and in 11 healthy controls. The correlation between leptin and nutritional parameters was analysed. (1) Serum leptin concentrations (3.0 +/- 2.5) micrograms/L in 42 subjects were significantly correlated with BMI, NW%, TSF, SSF and MAC (P leptin concentrations were significantly correlated with BMI in both malnourished patients with COPD and non-malnourished patients (P leptin level was significantly lower in malnourished group (1.3 +/- 1.0) micrograms/L than in non-malnourished group (4.5 +/- 2.6) micrograms/L, (P leptin level and BMI between non-malnourished group and healthy group were not significant. (3) Serum TNF-alpha level was significantly higher in COPD group (1.8 +/- 0.3) micrograms/L than in healthy group (1.0 +/- 0.5) microgram/L (P leptin levels didn't significantly correlate with TNF-alpha levels in COPD patients. Serum leptin levels correlate with nutritional parameters in COPD patients and leptin may contribute to the malnutrition in COPD patients.

  14. Anthropometric Parameters of Nutritional Status in Children with Cerebral Palsy.

    Science.gov (United States)

    Melunovic, Melika; Hadzagic-Catibusic, Feriha; Bilalovic, Vildan; Rahmanovic, Samra; Dizdar, Selma

    2017-03-01

    Patients with cerebral palsy (CP), besides the basic neurological damage, are also often undernourished. Adequate nutrition for children is very important during the period of intensive growth and development, which is of particular importance in patients with CP. To evaluate the nutritional status of patients with CP who are treated at the Pediatric Clinic, Clinical Centre of Sarajevo University and causes of malnutrition in these patients. Eighty patients with CP underwent anthropometric assessment (body weight, body height, body mass index, head circumference, subscapular skinfold thickness, triceps skinfold thickness and mid upper arm muscle circumference). Severity of CP was classified based on the Gross Motor Function Classification System (GMFCS). We compared the anthropometric parameters of our patients with normal values of healthy children, as well as with degree of motor impairment, oromotor dysfunction, feeding assistance, length of meals and daily feeding time. There were significant differences in all monitored parameters in relation to normal values, with 38 (47.5%) malnourished patients in the total group, out of which 29 (63.0%) with severe motor impairment and with 9 (11.3%) obese patients in the total group. The presence of oromotor dysfunction and other monitored parameters had a significant impact on the nutritional status of these patients. In severely disabled patients with CP there is a risk of profound malnutrition. Early identification and treatment of these patients is very important for their growth, development and health.

  15. Glue Film Thickness Measurements by Spectral Reflectance

    Energy Technology Data Exchange (ETDEWEB)

    B. R. Marshall

    2010-09-20

    Spectral reflectance was used to determine the thickness of thin glue layers in a study of the effect of the glue on radiance and reflectance measurements of shocked-tin substrates attached to lithium fluoride windows. Measurements based on profilometry of the components were found to be inaccurate due to flatness variations and deformation of the tin substrate under pressure during the gluing process. The accuracy of the spectral reflectance measurements were estimated to be ±0.5 μm, which was sufficient to demonstrate a convincing correlation between glue thickness and shock-generated light.

  16. Visual Ethnography, Thick Description and Cultural Representation

    Directory of Open Access Journals (Sweden)

    Dipesh Kharel

    2015-12-01

    Full Text Available The purposes of this paper are threefold: to cover historical, theoretical and methodological overview of visual ethnography (photography and film as a research tool in studying culture; to examine visual ethnography as a means of cultural representation, and to discuss visual ethnographic method with Clifford Geertz’s idea of “thick description”. I hope to bring some clarity and consensus to our understanding how visual ethnography can be an adequate research tool for “thick description” and a study of culture. Furthermore, in this paper, I begin by seeing visual ethnography in the context to visual anthropology, photography, ethnographic film, and semiotics.

  17. Electromagnetic imaging through thick metallic enclosures

    Directory of Open Access Journals (Sweden)

    Brendan J. Darrer

    2015-08-01

    Full Text Available The ability to image through metallic enclosures is an important goal of any scanning technology for security applications. Previous work demonstrated the penetrating power of electromagnetic imaging through thin metallic enclosures, thus validating the technique for security applications such as cargo screening. In this work we study the limits of electromagnetic imaging through metallic enclosures, considering the performance of the imaging for different thicknesses of the enclosure. Our results show, that our system can image a Copper disk, even when enclosed within a 20 mm thick Aluminum box. The potential for imaging through enclosures of other materials, such as Lead, Copper, and Iron, is discussed.

  18. Effect of geometry on hydrodynamic film thickness

    Science.gov (United States)

    Brewe, D. E.; Hamrock, B. J.; Taylor, C. M.

    1978-01-01

    The influence of geometry on the isothermal hydrodynamic film separating two rigid solids was investigated. Pressure-viscosity effects were not considered. The minimum film thickness is derived for fully flooded conjunctions by using the Reynolds boundary conditions. It was found that the minimum film thickness had the same speed, viscosity, and load dependence as Kapitza's classical solution. However, the incorporation of Reynolds boundary conditions resulted in an additional geometry effect. Solutions using the parabolic film approximation are compared with those using the exact expression for the film in the analysis. Contour plots are shown that indicate in detail the pressure developed between the solids.

  19. Boundary layer thickness effect on boattail drag

    Science.gov (United States)

    Blaha, B. J.; Chamberlain, R.; Bober, L. J.

    1976-01-01

    A combined experimental and analytical program was conducted to investigate the effects of boundary layer changes on the flow over high angle boattail nozzles. The tests were run on an isolated axisymmetric sting mounted model. Various boattail geometries were investigated at high subsonic speeds over a range of boundary layer thicknesses. In general, boundary layer effects were small at speeds up to Mach 0.8. However, at higher speeds significant regions of separated flow were present on the boattail. When separation was present large reductions in boattail drag resulted with increasing boundary layer thickness. The analysis predicts both of these trends.

  20. Differential impact of maternal and paternal ethnicity on the pattern of fat distribution in infants at age 3 months.

    Science.gov (United States)

    Kramer, C K; Hamilton, J K; Ye, C; Hanley, A J; Connelly, P W; Sermer, M; Zinman, B; Retnakaran, R

    2016-02-01

    As ethnicity is typically recorded as a single demographic variable in clinical studies, little is known about the relative impact of maternal vs. paternal ethnicity on fat distribution. The objective of this study was to determine whether there is a differential impact of maternal and paternal ethnicity on infant adiposity. Three hundred fifty-five infants underwent anthropometric assessment at age 3 months, including skin-fold thickness (SFT) measurement at subscapular, suprailiac and triceps. Maternal (M) and paternal (P) ethnicity were classified as white (M = 241, P = 252), Asian (M = 50, P = 42) or other (M = 64, P = 61). Infants with either Asian mother (compared with white) or Asian father (compared with white) had increased subscapular, suprailiac and triceps SFT (all P ethnicity (compared with white) independently predicted the likelihood of an infant being in the highest tertile for SFT at subscapular (odds ratio [OR] = 2.72, 95% confidence interval 1.17-6.34, P = 0.02), suprailiac (OR = 3.56, 1.51-8.42, P = 0.004) and triceps (OR = 3.26, 1.40-7.55, P = 0.005). In contrast, paternal Asian ethnicity was independently associated with sum of SFT only (OR = 2.46, 1.02-5.97, P = 0.04). Maternal and paternal Asian ethnicity have differential effects on infant fat distribution. Future clinical studies on obesity and fat composition should consider the distinct contributions of both parents to the ethnic classification of participants. © 2015 World Obesity.

  1. Fatigue behavior of thick composite single lap joints

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J.H.; Sridhar, I.; Srikanth, N. [Nanyang Technological Univ., Singapore (Singapore)

    2012-07-01

    In consideration of bondline thickness variability, in bonded joints where thick adherend is adopted, relative thick adhesive layer (2-5 mm) is preferable. This paper aims to give some insight in fatigue strength of adhesively bonded structures involving thick adherend coupled with thick adhesive layer. Single lap joints with nominal adherend thickness of 8 mm and two different nominal thicknesses (2.5 mm and 5.5 mm) were made and tested under fatigue loading. The failure mode exhibits always a tendency for interfacial initiation, followed by interlaminar separation. Fatigue strength for higher adhesive thickness is found to be lower. (Author)

  2. Anthropometry and body composition of adolescents in cracow, poland.

    Science.gov (United States)

    Klimek-Piotrowska, Wiesława; Koziej, Mateusz; Hołda, Mateusz K; Piątek, Katarzyna; Wszołek, Karolina; Tyszka, Anna; Kmiotek, Elizabeth; Pliczko, Mateusz; Śliwińska, Aleksandra; Krauss, Klaudia; Miszczyk, Marcin; Walocha, Jerzy

    2015-01-01

    The aim of the present study was to determine the level of adiposity and obesity in Polish adolescents and compare the results with earlier studies conducted in this population as well as those carried out in other populations. The study group consisted of 456 boys and 514 girls aged 14-18 years living in Cracow chosen from randomly selected secondary schools. Weight, height, waist, and hip circumference (WC, HC) as well as triceps, biceps, subscapular, and suprailiac skinfold thickness (SFT) were measured. Body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), subscapular/triceps skinfold ratio (STR), and percentage body fat were computed. The prevalence of overweight and obesity based on Polish children growth reference were calculated and age-dependent and gender-specific smoothed percentile curves for BMI and ROC curves were generated. Weight, height, WC, HC (up 16yr), WHtR (up 15yr), and WHR were considerably higher in males than females. Weight, height, and HC increased with age; WHtR remained the same. The prevalence of overweight and obesity were 10.2% (boys 10.3%; girls 10.1%) and 4.2% (boys 5.3%; girls 3.3%). ROC analysis revealed that WHtR was the best tool for detection of obesity (AUC of 0.982±0.007) in males, whereas the sum of four SFTs (AUC: 0.968±0.011) and WHtR (AUC: 0.963±0.012) were the best predictors of obesity in females. The level of adiposity in Cracow adolescents increased during the last decade. However, it is still lower than in other well-developed societies struggling with obesity epidemics.

  3. Myocardium wall thickness transducer and measuring method

    Science.gov (United States)

    Feldstein, C.; Lewis, G. W.; Silver, R. H.; Culler, V. H. (Inventor)

    1976-01-01

    A miniature transducer for measuring changes of thickness of the myocardium is described. The device is easily implantable without traumatizing the subject, without affecting the normal muscle behavior, and is removable and implantable at a different muscle location. Operating features of the device are described.

  4. Crustal thickness controlled by plate tectonics

    DEFF Research Database (Denmark)

    Artemieva, Irina M.; Meissner, Rolf

    2012-01-01

    /gabbro–eclogite phase transition in crustal evolution and the links between lithosphere recycling, mafic magmatism, and crustal underplating. We advocate that plate tectonics processes, togetherwith basalt/gabbro–eclogite transition, limit crustal thickness worldwide by providing effective mechanisms of crustal...

  5. Relationship between Central Corneal Thickness, Vitreous ...

    African Journals Online (AJOL)

    Shufelt C, Fraser-Bell S, Ying-Lai M, Torres M, Varma R. Refractive error, ocular biometry, and lens opalescence in an adult population: The Los Angeles Latino .... J. Age-related changes in central corneal thickness in normal eyes among the adult Lithuanian population. Clinical Interventions in Aging. 2014; 9: 1145-1151.

  6. Pathophysiology of Increased Fetal Nuchal Translucency Thickness

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2010-06-01

    Full Text Available Increased fetal nuchal translucency thickness is associated with trisomy 13, trisomy 18, trisomy 21, Turner syndrome, other sex chromosome abnormalities, as well as many fetal anomalies and genetic syndromes. This article provides a comprehensive review of the cardinal proposed pathophysiology including altered composition of the extracellular matrix, abnormalities of the heart and great arteries, and disturbed or delayed lymphatic development.

  7. Thick tool steel coatings with laser cladding

    NARCIS (Netherlands)

    Ocelik, V.; de Oliveira, U.; De Hosson, J. Th. M.; DeHosson, JTM; Brebbia, CA; Nishida, SI

    2007-01-01

    This paper concentrates on thick and crack-free laser clad coatings (up to 3 mm). The coating material is a chromium-molybdenum-tungsten-vanadium alloyed high-speed steel that shows high wear resistance, high compressive strength, good toughness, very good dimensional stability on heat treatment and

  8. ORIGINAL ARTICLE Sonographic gallbladder wall thickness in ...

    African Journals Online (AJOL)

    Aim. The aim of the study was to determine the ultrasonic gallbladder wall thickness in normal adult Nigerians so as to create standards for defining gallbladder abnormalities in Nigerians. Method. Four hundred adults comprising 228 (57%) women and 172. (43%) men aged 16 - 78 years, who had normal clinical history ...

  9. Percolation effect in thick film superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Sali, R.; Harsanyi, G. [Technical Univ. of Budapest (Hungary)

    1994-12-31

    A thick film superconductor paste has been developed to study the properties of granulated superconductor materials, to observe the percolation effect and to confirm the theory of the conducting mechanism in the superconducting thick films. This paste was also applied to make a superconducting planar transformer. Due to high T{sub c} and advantageous current density properties the base of the paste was chosen to be of Bi(Pb)SrCaCuO system. For contacts a conventional Ag/Pt paste was used. The critical temperature of the samples were between 110 K and 115 K depending on the printed layer thickness. The critical current density at the boiling temperature of the liquid He- was between 200-300 A/cm{sup 2}. The R(T) and V(I) functions were measured with different parameters. The results of the measurements have confirmed the theory of conducting mechanism in the material. The percolation structure model has been built and described. As an application, a superconducting planar thick film transformer was planned and produced. Ten windings of the transformer were printed on one side of the alumina substrate and one winding was printed on the other side. The coupling between the two sides was possible through the substrate. The samples did not need special drying and firing parameters. After the preparation, the properties of the transformer were measured. The efficiency and the losses were determined. Finally, some fundamental advantages and problems of the process were discussed.

  10. Preparation and study of thickness dependent electrical ...

    Indian Academy of Sciences (India)

    Unknown

    thickness decreased from 332 nm to 76 nm. The structural and activation energy studies support this decrease ... layer heterojunction solar cells (Ortega Borges et al. 1992). Zinc sulfide has found wide use as a thin film ..... 11th European photovoltaic solar energy conference, Mont- reaux. Padam G K, Malhotra G L and Rao ...

  11. Thick Slice and Thin Slice Teaching Evaluations

    Science.gov (United States)

    Tom, Gail; Tong, Stephanie Tom; Hesse, Charles

    2010-01-01

    Student-based teaching evaluations are an integral component to institutions of higher education. Previous work on student-based teaching evaluations suggest that evaluations of instructors based upon "thin slice" 30-s video clips of them in the classroom correlate strongly with their end of the term "thick slice" student evaluations. This study's…

  12. Determination of the Optimum Thickness of Approximately ...

    African Journals Online (AJOL)

    In an attempt to conserve the world's scarce energy and material resources, a balance between the cost of heating a material and the optimum thickness of the material becomes vey essential. One of such materials is the local cast aluminium pot commonly used as cooking ware in Nigeria. This paper therefore sets up a ...

  13. Extensive calvarial exposure and full thickness sequestration ...

    African Journals Online (AJOL)

    Background: Calvarial osteomyelitis is an uncommon complication of burn injury due to electricity. Patient: A case of electrical injury that progressed from full thickness scalp loss to calvarial osteomyelitis and sequestration of outer and inner tables seen after one year of calvarial exposure is presented. Result: The patient ...

  14. Preparation and study of thickness dependent electrical ...

    Indian Academy of Sciences (India)

    Zinc sulfide thin films have been deposited onto glass substrates by chemical bath deposition. The various deposition parameters such as volume of sulfide ion source, pH of bath, deposition time, temperature etc are optimized. Thin films of ZnS with different thicknesses of 76–332 nm were prepared by changing the ...

  15. Improved nucleonic coal-thickness monitor

    Science.gov (United States)

    Crouch, C. E.; Rose, S. D.; Jones, E. W.

    1979-01-01

    Design for coal-thickness-sensing instrument features independent hydropneumatic suspension of radiation source and detector. Monitor uses source and detector which are independently mounted, to follow contour of coal surface more closely and to eliminate errors caused by variations in airgap along radiation path. Device may help to bring fully-automated coal mining closer to reality.

  16. Factors Influencing Endometrial Thickness in Postmenopausal Women

    African Journals Online (AJOL)

    Background: Cut‑off values for endometrial thickness (ET) in asymptomatic postmenopausal woman have been standardized. However, there are no comprehensive studies to document how various factors can influence the ET after the age of menopause. Aim: To study the various factors influencing the ET in ...

  17. Relationship between Central Corneal Thickness, Vitreous ...

    African Journals Online (AJOL)

    The central corneal thickness (CCT), Vitreous chamber depth (VCD) and axial length (AL) are important ocular parameters used in the assessment of ocular health in relation to some ocular morbidities. Determining the differences in these parameters in relation to each other is fundamental to understanding the general eye ...

  18. The Relationship between Central Corneal Thickness and ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the relationship between central corneal thickness (CCT) and intraocular pressure (IOP) in a predominantly black population. A total of eighty-five subjects (right eyes) with mean age 44.7 ± 15.1 years consisting of 49 males and 36 females were recruited for this study. The central ...

  19. Alcoholic chronic pancreatitis: A quality of life study

    Directory of Open Access Journals (Sweden)

    Simone Carla BENINCÁ

    2016-02-01

    Full Text Available ABSTRACT Objective: To compare the quality of life between patients with alcoholic chronic pancreatitis and controls, and between diabetic and non-diabetic patients, correlating clinical, sociodemographic, and nutritional factors with their quality of life scores. Methods: Forty-three outpatients of the pancreas and biliary tract clinic diagnosed with alcoholic chronic pancreatitis were assessed. Quality of life was measured by the Brazilian version of the Short Form-36. The control group consisted of 43 healthy companions. Nutritional status was classified according to body mass index and triceps, biceps, suprailiac, and subscapular skinfold thicknesses, using the appropriate methods. The percentage of body fat was given by adding the four skinfold thicknesses and by bioelectrical impedance analysis. The statistical tests included the Chi-square, Mann-Whitney, and Spearman's correlation tests, with the significance level set at p<0.05. Results: The sociodemographic variables of the case and control groups did not differ. Quality of life was lower in alcoholic chronic pancreatitis patients than in controls. The only quality of life domain that differed between diabetics and non-diabetics was functional capacity, lower in diabetics (p=0.022. Smoking duration, alcohol intake in grams, and time since pancreatic surgery correlated negatively with the quality of life of alcoholic chronic pancreatitis patients. Old age, skinfold thicknesses, and percentage of body fat correlated positively with quality of life. Conclusion: Quality of life is low in alcoholic chronic pancreatitis patients because of the negative influence of certain factors, such as smoking duration, amount of alcohol consumed, and time since pancreatic surgery.

  20. Breast-feeding Duration, Age of Starting Solids, and High BMI Risk and Adiposity in Indian Children

    Science.gov (United States)

    2011-01-01

    This study utilized data from a prospective birth cohort study on 568 Indian children, to determine whether a longer duration of breast-feeding and later introduction of solid feeding was associated with a reduced higher body mass index (BMI) and less adiposity. Main outcomes were high BMI (>90th within-cohort sex-specific BMI percentile) and sum of skinfold thickness (triceps and subscapular) at age 5. Main exposures were breast-feeding (6 categories from 1-4 to ≥21 months) and age of starting regular solid feeding (4 categories from ≤3 to ≥6 months). Data on infant feeding practices, socioeconomic and maternal factors were collected by questionnaire. Birthweight, maternal and child anthropometry were measured. Multiple regression analysis which accounted for potential confounders, demonstrated a small magnitude of effect for breast-feeding duration or introduction of solid feeds on the risk of high BMI but not for lower skinfold thickness. Breast-feeding duration was strongly negatively associated with weight gain (0-2 years) (adjusted β= −0.12 SD 95% CI: −0.19 to −0.05 per category change in breast-feeding duration, p=0.001) and weight gain (0-2 years) was strongly associated with high BMI at 5 years (adjusted OR = 3.8, 95 % CI: 2.53 to 5.56, pbreast-feeding duration and later introduction of solids has a small reduction on later high BMI risk and a negligible effect on skinfold thickness. However, accounting for sampling variability, these findings cannot exclude the possibility of no effect at the population-level. PMID:21978208

  1. A prospective study of LINE-1DNA methylation and development of adiposity in school-age children.

    Science.gov (United States)

    Perng, Wei; Mora-Plazas, Mercedes; Marín, Constanza; Rozek, Laura S; Baylin, Ana; Villamor, Eduardo

    2013-01-01

    Repetitive element DNA methylation is related to prominent obesity-related chronic diseases including cancer and cardiovascular disease; yet, little is known of its relation with weight status. We examined associations of LINE-1 DNA methylation with changes in adiposity and linear growth in a longitudinal study of school-age children from Bogotá, Colombia. We quantified methylation of LINE-1 elements from peripheral leukocytes of 553 children aged 5-12 years at baseline using pyrosequencing technology. Anthropometric characteristics were measured periodically for a median of 30 months. We estimated mean change in three age-and sex-standardized indicators of adiposity: body mass index (BMI)-for-age Z-score, waist circumference Z-score, and subscapular-to-triceps skinfold thickness ratio Z-score according to quartiles of LINE-1 methylation using mixed effects regression models. We also examined associations with height-for-age Z-score. There were non-linear, inverse relations of LINE-1 methylation with BMI-for-age Z-score and the skinfold thickness ratio Z-score. After adjustment for baseline age and socioeconomic status, boys in the lowest quartile of LINE-1 methylation experienced annual gains in BMI-for-age Z-score and skinfold thickness ratio Z-score that were 0.06 Z/year (P = 0.04) and 0.07 Z/year (P = 0.03), respectively, higher than those in the upper three quartiles. The relation of LINE-1 methylation and annual change in waist circumference followed a decreasing monotonic trend across the four quartiles (P trend = 0.02). DNA methylation was not related to any of the adiposity indicators in girls. There were no associations between LINE-1 methylation and linear growth in either sex. Lower LINE-1 DNA methylation is related to development of adiposity in boys.

  2. Breastfeeding duration, age of starting solids and high BMI risk and adiposity in Indian children.

    Science.gov (United States)

    Caleyachetty, Amrit; Krishnaveni, Ghattu V; Veena, Sargoor R; Hill, Jacqui; Karat, Samuel C; Fall, Caroline H D; Wills, Andrew K

    2013-04-01

    This study utilized data from a prospective birth cohort study on 568 Indian children, to determine whether a longer duration of breastfeeding and later introduction of solid feeding were associated with a reduced higher body mass index (BMI) and less adiposity. Main outcomes were high BMI (>90th within-cohort sex-specific BMI percentile) and sum of skinfold thickness (triceps and subscapular) at age 5. Main exposures were breastfeeding (six categories from 1-4 to ≥21 months) and age of starting regular solid feeding (four categories from ≤3 to ≥6 months). Data on infant-feeding practices, socio-economic and maternal factors were collected by questionnaire. Birthweight, maternal and child anthropometry were measured. Multiple regression analysis that accounted for potential confounders demonstrated a small magnitude of effect for breastfeeding duration or introduction of solid feeds on the risk of high BMI but not for lower skinfold thickness. Breastfeeding duration was strongly negatively associated with weight gain (0-2 years) [adjusted β = -0.12 standard deviation, 95% confidence interval (CI): -0.19 to -0.05 per category change in breastfeeding duration, P = 0.001], and weight gain (0-2 years) was strongly associated with high BMI at 5 years (adjusted odds ratio = 3.8, 95% CI: 2.53-5.56, P BMI risk and a negligible effect on skinfold thickness. However, accounting for sampling variability, these findings cannot exclude the possibility of no effect at the population level. © 2011 Blackwell Publishing Ltd.

  3. Nearshore sediment thickness, Fire Island, New York

    Science.gov (United States)

    Locker, Stanley D.; Miselis, Jennifer L.; Buster, Noreen A.; Hapke, Cheryl J.; Wadman, Heidi M.; McNinch, Jesse E.; Forde, Arnell S.; Stalk, Chelsea A.

    2017-04-03

    Investigations of coastal change at Fire Island, New York (N.Y.), sought to characterize sediment budgets and determine geologic framework controls on coastal processes. Nearshore sediment thickness is critical for assessing coastal system sediment availability, but it is largely unquantified due to the difficulty of conducting geological or geophysical surveys across the nearshore. This study used an amphibious vessel to acquire chirp subbottom profiles. These profiles were used to characterize nearshore geology and provide an assessment of nearshore sediment volume. Two resulting sediment-thickness maps are provided: total Holocene sediment thickness and the thickness of the active shoreface. The Holocene sediment section represents deposition above the maximum flooding surface that is related to the most recent marine transgression. The active shoreface section is the uppermost Holocene sediment, which is interpreted to represent the portion of the shoreface thought to contribute to present and future coastal behavior. The sediment distribution patterns correspond to previously defined zones of erosion, accretion, and stability along the island, demonstrating the importance of sediment availability in the coastal response to storms and seasonal variability. The eastern zone has a thin nearshore sediment thickness, except for an ebb-tidal deposit at the wilderness breach caused by Hurricane Sandy. Thicker sediment is found along a central zone that includes shoreface-attached sand ridges, which is consistent with a stable or accretional coastline in this area. The thickest overall Holocene section is found in the western zone of the study, where a thicker lower section of Holocene sediment appears related to the westward migration of Fire Island Inlet over several hundred years.

  4. Is adductor pollicis muscle thickness a good predictor of lean mass in adults?

    Science.gov (United States)

    Bielemann, Renata Moraes; Horta, Bernardo Lessa; Orlandi, Silvana Paiva; Barbosa-Silva, Thiago Gonzalez; Gonzalez, Maria Cristina; Assunção, Maria Cecília; Gigante, Denise Petrucci

    2016-10-01

    Lean mass (LM) is an important parameter in clinical outcomes, which highlights the necessity of reliable tools for its estimation. The adductor pollicis muscle thickness (APMT) is easily accessible and suffers minimal interference from the adjacent subcutaneous fat tissue. To assess the relationship between the APMT and LM in a sample of Southern Brazilian adults. Participants were adults from the 1982 Pelotas (Brazil) Birth Cohort. LM was measured by dual energy X-ray absorptiometry (DXA). LM and lean mass index (LMI - LM divided by the square of height - kg/m(2)) were the outcomes. APMT was measured using a skinfold caliper. The mean of three measurements in the non-dominant hand was used in the analyses. APMT was described according to socio-demographic characteristics and nutritional status. The relationship between APMT and both LM and LMI was evaluated by correlation coefficient and linear regression using APMT as a single anthropometric parameter and also in addition to BMI. APMT was assessed in 3485 participants. APMT was higher in males, non-whites, less-schooled and obese individuals. APMT was moderately correlated to LM and LMI (ranged from 0.44 to 0.57). Correlation coefficients were higher for LMI as outcome and in females (LM: 0.51 and LMI: 0.57). APMT explained 19% and 26% of the variance in LM in males and females, respectively, whereas it explained 26% and 33% of the variance in LMI. APMT increased the prediction for LM in 3 and 4 percentage points in males and females, in comparison to explained by BMI. BMI explained 48% and 59% of the variance of LMI in males and females whereas APMT increased it to 51% and 62% for both sexes, respectively. Results were not good enough to promote the APMT as a single predictor of LM or LMI in epidemiological studies. APMT has a little predictive capacity in estimating LM or LMI when BMI is also considered. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Clinical significance of central corneal thickness and comparison of central corneal thickness

    Directory of Open Access Journals (Sweden)

    Özgür Çakıcı

    2014-03-01

    Full Text Available Significance of central corneal thickness has been increasing in ophthalmology practice. It is an important clinical evaluation tool especially prior to refractive surgery and in diagnosis of glaucoma and keratoconus. Refractive surgery is planned according to preoperative central corneal thickness measurements. Besides, in order to determine actual intraocular pressure, central corneal thickness is measured and corrected eye pressure is obtained. Today, devices used in measurement of central corneal thickness do the measurement according to two principles. First and relatively older method is ultrasonic method. Optic method is the second and more recent method. In daily practice, the most commonly used clinical method in measurement of central corneal thickness is ultrasound pachymeter. However, this measurement technique requires contact between cornea and probe and gives thinner measurement results compared to the methods that use optic principle. Recently, several technologic methods based on optics have been put in use; they provide advantages of non-contact technique and objective determination of central corneal thickness. Of these methods, most commonly used include Specular Microscopy, Optical coherence tomography, Laser Doppler Interferometry, Optical low coherence reflectometry pachymetry, Optic based topographic mapping (also called screening section pachymetry and Pentacam. In this article, it was aimed to evaluate importance of central corneal thickness in clinical use and compare measurement methods. J Clin Exp Invest 2014; 5 (1: 153-158

  6. Correlates of eggshell thickness | Okereke | Global Journal of Pure ...

    African Journals Online (AJOL)

    This study discussed the effects of age and genotype of birds and location of farm on eggshell thickness. The ultimate objective of the study is to determine the correlates of eggshell thickness which may be relevant to improve eggshell thickness. Secondary data on eggshell thickness collected from the Agricultural ...

  7. Buckling Response of Thick Functionally Graded Plates

    Directory of Open Access Journals (Sweden)

    BOUAZZA MOKHTAR

    2014-11-01

    Full Text Available In this paper, the buckling of a functionally graded plate is studied by using first order shear deformation theory (FSDT. The material properties of the plate are assumed to be graded continuously in the direction of thickness. The variation of the material properties follows a simple power-law distribution in terms of the volume fractions of constituents. The von Karman strains are used to construct the equilibrium equations of the plates subjected to two types of thermal loading, linear temperature rise and gradient through the thickness are considered. The governing equations are reduced to linear differential equation with boundary conditions yielding a simple solution procedure. In addition, the effects of temperature field, volume fraction distributions, and system geometric parameters are investigated. The results are compared with the results of the no shear deformation theory (classic plate theory, CPT.

  8. Properties of conductive thick-film inks

    Science.gov (United States)

    Holtze, R. F.

    1972-01-01

    Ten different conductive inks used in the fabrication of thick-film circuits were evaluated for their physical and handling properties. Viscosity, solid contents, and spectrographic analysis of the unfired inks were determined. Inks were screened on ceramic substrates and fired for varying times at specified temperatures. Selected substrates were given additional firings to simulate the heat exposure received if thick-film resistors were to be added to the same substrate. Data are presented covering the (1) printing characteristics, (2) solderability using Sn-63 and also a 4 percent silver solder, (3) leach resistance, (4) solder adhesion, and (5) wire bonding properties. Results obtained using different firing schedules were compared. A comparison was made between the various inks showing general results obtained for each ink. The changes in firing time or the application of a simulated resistor firing had little effect on the properties of most inks.

  9. Compressive strength of thick composite panels

    DEFF Research Database (Denmark)

    Branner, Kim; Berring, Peter

    2011-01-01

    The aim of this study is to investigate how much the compressive strength of thick composite panels is reduced due to delaminations and to investigate under which conditions a delamination will grow. Understanding of this is essential in order to move forward the design limits used in the structu......The aim of this study is to investigate how much the compressive strength of thick composite panels is reduced due to delaminations and to investigate under which conditions a delamination will grow. Understanding of this is essential in order to move forward the design limits used...... in the structural design process. Results obtained from finite element modeling analyses are compared with an experimental test campaign performed on flat composite panels with and without delaminations....

  10. Hybrid Optimization for Wind Turbine Thick Airfoils

    Energy Technology Data Exchange (ETDEWEB)

    Grasso, F. [ECN Wind Energy, Petten (Netherlands)

    2012-06-15

    One important element in aerodynamic design of wind turbines is the use of specially tailored airfoils to increase the ratio of energy capture and reduce cost of energy. This work is focused on the design of thick airfoils for wind turbines by using numerical optimization. A hybrid scheme is proposed in which genetic and gradient based algorithms are combined together to improve the accuracy and the reliability of the design. Firstly, the requirements and the constraints for this class of airfoils are described; then, the hybrid approach is presented. The final part of this work is dedicated to illustrate a numerical example regarding the design of a new thick airfoil. The results are discussed and compared to existing airfoils.

  11. Best focus shift mechanism for thick masks

    Science.gov (United States)

    Burkhardt, Martin; Raghunathan, Ananthan

    2015-03-01

    The best focus shift due to thick mask effects is well known, both in ArF, and more importantly in EUV, where the shorter wavelength is small compared to both mask openings and absorber height. While the effect is stronger in opaque features in clear field masks, the best focus shift is visible in dark field masks as well, and it becomes even more pronounced when scattering bars are added to non-dense features. This pattern dependent focus variation can be predicted in both exact EMF simulations and fast image calculations that are used for optical proximity correction (OPC). Even though this focus shift can be predicted and patterns can be corrected in OPC, we would like to understand the mechanism that causes this focus shift. This can help us understand if, in addition to best focus shift, the image quality is further deteriorated due to the thick mask effects. The best focus shift is found to be an interplay of the complex diffraction coefficient due to thick mask effects and the direction of the light that is incident on the mask, or coherence value σ. A change in focus adds a phase term to each of the complex diffraction coefficients, causing their rotation in a phasor diagram. Best focus is found when the phasors have an angle of 0 or 180 degrees to each other and depending on which diffracted orders are caught in the pupil and contribute to imaging. We investigate the effect of partial coherence, mask thickness, and assist feature placement on best focus shift. We observe a waveguide effect in the absorber gaps because of the reduced real index of refraction in the absorber layer, making vacuum the optically dense medium. We suggest ways to lessen the best focus shifts through assist feature placement or the use of alternative absorbers that are closer matched to the dielectric index of vacuum.

  12. Saturn's rings thickness with the shadow hiding

    Science.gov (United States)

    Deau, Estelle; Brahic, André; Porco, Carolyn

    Using the Hapke shadow hiding model on various curves phases of ISS/Cassini, we were able to compute the thickness of Saturn's rings through the photometric filling factor. Our results show that diffuse rings (C ring and Cassini Division) are distributed in a monolayer with a thickness from a few centimeters to 5 meters. This seems to suggest that the layer is smaller than the larger particles. For the A and B rings, we find a thickness ranging from 10 to 20 meters, then leading to multiple layers of particles. Our results for the A ring are systematically lower than the values derived by density waves (Tiscareno et al., 2007) and dynamical simulations of Salo and Kaarjalainen (2003). For the first one, this can be explain by the fact the vertical height of the density waves are the upper limit of the real height. Indeed, the wakes (Julian & Toomre, 1966; Salo 1995) conduce the viscosity in the A ring (Daisaka et al., 2001), and produce random speeds greater in the ring plane than in the vertical direction (Daisaka & Ida, 1999), thereby reducing the thickness given by the vertical random speed used to compute the vertical height. However, for the latter one, simulations lead in all the cases (A and B rings such as C ring and Cassini Division) to vertical height of few meters. This constancy can be explained by the fact that simulations take a size distribution too truncated, and a coefficient of restitution rather simple (indeed, rings reflect different surface conditions related to the optical depth, thus the Bridges' law could not promote only one type of collisions). Finally, our results prefer monolayer (layer smaller than the larger particles which allow multilayer of smaller particules) for the faint rings (C ring and Cassini Division) and multilayer for the A and B rings.

  13. A de Sitter tachyon thick braneworld

    Science.gov (United States)

    Germán, Gabriel; Herrera-Aguilar, Alfredo; Malagón-Morejón, Dagoberto; Rigel Mora-Luna, Refugio; da Rocha, Roldão

    2013-02-01

    Among the multiple 5D thick braneworld models that have been proposed in the last years, in order to address several open problems in modern physics, there is a specific one involving a tachyonic bulk scalar field. Delving into this framework, a thick braneworld with a cosmological background induced on the brane is here investigated. The respective field equations — derived from the model with a warped 5D geometry — are highly non-linear equations, admitting a non-trivial solution for the warp factor and the tachyon scalar field as well, in a de Sitter 4D cosmological background. Moreover, the non-linear tachyonic scalar field, that generates the brane in complicity with warped gravity, has the form of a kink-like configuration. Notwithstanding, the non-linear field equations restricting character does not allow one to easily find thick brane solutions with a decaying warp factor which leads to the localization of 4D gravity and other matter fields. We derive such a thick brane configuration altogether in this tachyon-gravity setup. When analyzing the spectrum of gravity fluctuations in the transverse traceless sector, the 4D gravity is shown to be localized due to the presence of a single zero mode bound state, separated by a continuum of massive Kaluza-Klein (KK) modes by a mass gap. It contrasts with previous results, where there is a KK massive bound excitation providing no clear physical interpretation. The mass gap is determined by the scale of the metric parameter H. Finally, the corrections to Newton's law in this model are computed and shown to decay exponentially. It is in full compliance to corrections reported in previous results (up to a constant factor) within similar braneworlds with induced 4D de Sitter metric, despite the fact that the warp factor and the massive modes have a different form.

  14. Nanocrystalline diamond enhanced thickness shear mode resonator

    OpenAIRE

    WILLIAMS, Oliver; MORTET, Vincent; DAENEN, Michael; HAENEN, Ken

    2007-01-01

    A nanocrystalline diamond coated thickness shear mode resonator has been fabricated as an alternative to the quartz crystal microbalance. Due to the low temperature phase transition of quartz, the piezoelectric material was replaced with langasite, a piezoelectric with no phase transition up to its melting point. The resulting device shows clear resonant behavior and oscillates in both air and in liquid. The diamond coating shows clear faceting by scanning electron microscopy and sp(3) bondin...

  15. Nanocrystalline diamond enhanced thickness shear mode resonator

    Science.gov (United States)

    Williams, Oliver A.; Mortet, Vincent; Daenen, Michael; Haenen, Ken

    2007-02-01

    A nanocrystalline diamond coated thickness shear mode resonator has been fabricated as an alternative to the quartz crystal microbalance. Due to the low temperature phase transition of quartz, the piezoelectric material was replaced with langasite, a piezoelectric with no phase transition up to its melting point. The resulting device shows clear resonant behavior and oscillates in both air and in liquid. The diamond coating shows clear faceting by scanning electron microscopy and sp3 bonding by Raman spectroscopy.

  16. A de Sitter tachyon thick braneworld

    Energy Technology Data Exchange (ETDEWEB)

    Germán, Gabriel; Herrera-Aguilar, Alfredo; Malagón-Morejón, Dagoberto [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Apdo. Postal 48-3, 62251, Cuernavaca, Morelos (Mexico); Mora-Luna, Refugio Rigel [Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo, Edificio C-3, Ciudad Universitaria, C.P. 58040, Morelia, Michoacán (Mexico); Rocha, Roldão da, E-mail: gabriel@fis.unam.mx, E-mail: aha@fis.unam.mx, E-mail: malagon@ifm.umich.mx, E-mail: rigel@ifm.umich.mx, E-mail: roldao.rocha@ufabc.edu.br [Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Rua Santa Adélia, 166 09210-170, Santo André, SP (Brazil)

    2013-02-01

    Among the multiple 5D thick braneworld models that have been proposed in the last years, in order to address several open problems in modern physics, there is a specific one involving a tachyonic bulk scalar field. Delving into this framework, a thick braneworld with a cosmological background induced on the brane is here investigated. The respective field equations — derived from the model with a warped 5D geometry — are highly non-linear equations, admitting a non-trivial solution for the warp factor and the tachyon scalar field as well, in a de Sitter 4D cosmological background. Moreover, the non-linear tachyonic scalar field, that generates the brane in complicity with warped gravity, has the form of a kink-like configuration. Notwithstanding, the non-linear field equations restricting character does not allow one to easily find thick brane solutions with a decaying warp factor which leads to the localization of 4D gravity and other matter fields. We derive such a thick brane configuration altogether in this tachyon-gravity setup. When analyzing the spectrum of gravity fluctuations in the transverse traceless sector, the 4D gravity is shown to be localized due to the presence of a single zero mode bound state, separated by a continuum of massive Kaluza-Klein (KK) modes by a mass gap. It contrasts with previous results, where there is a KK massive bound excitation providing no clear physical interpretation. The mass gap is determined by the scale of the metric parameter H. Finally, the corrections to Newton's law in this model are computed and shown to decay exponentially. It is in full compliance to corrections reported in previous results (up to a constant factor) within similar braneworlds with induced 4D de Sitter metric, despite the fact that the warp factor and the massive modes have a different form.

  17. Intima-Media Thickness in Severe Obesity

    OpenAIRE

    Dalmas, Elise; Kahn, Jean-François; Giral, Philippe; Abdennour, Meriem; Bouillot, Jean-Luc; Fellahi, Soraya; Oppert, Jean-Michel; Clément, Karine; Guerre-Millo, Michèle; Poitou, Christine

    2013-01-01

    OBJECTIVE Obesity is associated with cardiovascular risk and a low-grade inflammatory state in both blood and adipose tissue (AT). Whether inflammation contributes to vascular alteration remains an open question. To test this hypothesis, we measured arterial intima-media thickness (IMT), which reflects subclinical atherosclerosis, in severely obese subjects and explored associations with systemic inflammation and AT inflammation. RESEARCH DESIGN AND METHODS IMT of the carotid artery (C-IMT) a...

  18. Accelerating Thick Aluminum Liners Using Pulsed Power

    Energy Technology Data Exchange (ETDEWEB)

    Kyrala, G.A.; Hammerburg, J.E.; Bowers, D.; Stokes, J.; Morgan, D.V.; Anderson, W.E.; Cochrane, J.C.

    1999-06-28

    The authors have investigated the acceleration of very thick cylindrical aluminum liners using the Pegasus II capacitory bank. These accelerated solid liners will be used to impact other objects at velocities below 1.5 km/sec, allowing one to generate and sustain shocks of a few 100 kilobar for a few microseconds. A cylindrical shell of 1100 series aluminum with an initial inner radius of 23.61 mm, an initial thickness of 3.0 mm, and a height of 20 mm, was accelerated using a current pulse of 7.15 MA peak current and a 7.4 microsecond quarter cycle time. The aluminum shell was imploded within confining copper glide planes with decreasing separation with an inward slope of 8 degrees. At impact with a cylindrical target of diameter 3-cm, the liner was moving at 1.4 km/sec and its thickness increased to 4.5 mm. Radial X-ray radiograms of the liner showed both the liner and the glide plane interface. The curvature of the inner surface of the liner was measured before impact with the 15-mm radius target. The radiograms also showed that the copper glide planes distorted as the liner radius decreased and that some axial stress is induced in the liner. The axial stresses did not affect the inner curvature significantly. Post-shot calculations of the liner behavior indicated that the thickness of the glide plane played a significant role in the distortion of the interface between the liner and the glide plane.

  19. The spontaneous puncture of thick liquid films

    Science.gov (United States)

    Néel, Baptiste; Villermaux, Emmanuel

    2016-11-01

    We call thick those films for which the disjoining pressure is ineffective. Water films with thickness h in the 1-10 μm range are thick, but it is also known that, paradoxically, they nucleate holes spontaneously. We have uncovered a mechanism solving the paradox. Most natural films are dirty to some extent, and we show that if a spot of dissolved substance lowers locally the surface tension of the liquid, the corresponding Marangoni stress may lead to a self-sustained instability triggering film rupture. When deposited with size a, the spot dissipates by molecular diffusion (coefficient D) along the film in a time a2 / D . Before doing so, the surface tension gradient Δσ / a between the spot center (tension σ - Δσ) and the rest of the film (tension σ) induces an inhomogeneous outward interstitial flow which digs the spot, and reinforces the tension gradient. Hence the instability, which occurs within a timescale τ √{ ρa2 h / Δσ } , with ρ the liquid density. When the Péclet number Pe =a2 / Dτ is small, diffusion regularizes the film, which remains flat: clean films don't break, while for Pe > 1 , the film punctures. This new scenario will be illustrated by several experiments.

  20. Factors Affecting the Thickness of Thermal Aureoles

    Directory of Open Access Journals (Sweden)

    Catherine Annen

    2017-10-01

    Full Text Available Intrusions of magma induce thermal aureoles in the country rock. Analytical solutions predict that the thickness of an aureole is proportional to the thickness of the intrusion. However, in the field, thermal aureoles are often significantly thinner or wider than predicted by simple thermal models. Numerical models show that thermal aureoles are wider if the heat transfer in the magma is faster than in the country rock due to contrasts in thermal diffusivities or the effect of magma convection. Large thermal aureoles can also be caused by repeated injection close to the contact. Aureoles are thin when heat transfer in the country rock is faster than heat transfer within the magma or in case of incrementally, slowly emplaced magma. Absorption of latent heat due to metamorphic reactions or water volatilization also affects thermal aureoles but to a lesser extent. The way these parameters affect the thickness of a thermal aureole depends on the isotherm under consideration, hence on which metamorphic phase is used to draw the limit of the aureole. Thermal aureoles provide insight on the dynamics of intrusions emplacement. Although available examples are limited, asymmetric aureoles point to magma emplacement by over-accretion for mafic cases and by under-accretion for felsic cases, consistent with geochronological data.

  1. Thickness Distribution of Glenohumeral Joint Cartilage.

    Science.gov (United States)

    Schleich, Christoph; Bittersohl, Bernd; Antoch, Gerald; Krauspe, Rüdiger; Zilkens, Christoph; Kircher, Jörn

    2017-04-01

    High-resolution 3-dimensional cartilage-specific magnetic resonance imaging (MRI) was performed at 3 T to test the following hypotheses: (1) there is a nonuniform cartilage thickness distribution both on the proximal humerus and on the glenoid surface and (2) the glenohumeral joint as a combined system is congruent with the level of the joint cartilage surface without substantial radial mismatch. Inclusion of 38 volunteers (19 females, mean age 24.34 ± 2.22 years; range 21-29 years) in a prospective study. Measurements of: cartilage thickness in 3 regions and 3 zones; radius of both circles (glenoid and humeral cartilage) for congruency calculation using 3-T MRI with 3-dimensional dual-echo steady-state sequence with water excitation. A homogenous mean cartilage thickness (1.2-1.5 mm) and slightly higher values for the glenoidal articulating surface radii both in the mid-paracoronar section (2.4 vs. 2.1 cm, P cartilage changes at the shoulder for future studies.

  2. Cranial vault thickness in primates: Homo erectus does not have uniquely thick vault bones.

    Science.gov (United States)

    Copes, Lynn E; Kimbel, William H

    2016-01-01

    Extremely thick cranial vaults have been noted as a diagnostic characteristic of Homo erectus since the first fossil of the species was identified, but relatively little work has been done on elucidating its etiology or variation across fossils, living humans, or extant non-human primates. Cranial vault thickness (CVT) is not a monolithic trait, and the responsiveness of its layers to environmental stimuli is unknown. We obtained measurements of cranial vault thickness in fossil hominins from the literature and supplemented those data with additional measurements taken on African fossil specimens. Total CVT and the thickness of the cortical and diploë layers individually were compared to measures of CVT in extant species measured from more than 500 CT scans of human and non-human primates. Frontal and parietal CVT in fossil primates was compared to a regression of CVT on cranial capacity calculated for extant species. Even after controlling for cranial capacity, African and Asian H. erectus do not have uniquely high frontal or parietal thickness residuals, either among hominins or extant primates. Extant primates with residual CVT thickness similar to or exceeding H. erectus (depending on the sex and bone analyzed) include Nycticebus coucang, Perodicticus potto, Alouatta caraya, Lophocebus albigena, Galago alleni, Mandrillus sphinx, and Propithecus diadema. However, the especially thick vaults of extant non-human primates that overlap with H. erectus values are composed primarily of cortical bone, while H. erectus and other hominins have diploë-dominated vault bones. Thus, the combination of thick vaults comprised of a thickened diploë layer may be a reliable autapomorphy for members of the genus Homo. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Extragalactic Thick Disks: Implications for Early Galaxy Evolution

    OpenAIRE

    Dalcanton, Julianne J.; Seth, Anil; Yoachim, Peter

    2005-01-01

    I briefly review the growing evidence that thick stellar disks surround most edge-on disk galaxies. Recent studies show that these extragalactic thick disks have old ages, low metallicities, long scale lengths, and moderately flattened axial ratios, much like the thick disk of the Milky Way. However, the properties of thick disks change systematically with the mass of the galaxy. The thick disks of low mass galaxies are more prominent and somewhat more metal-poor than those surrounding massiv...

  4. [Additional cardiovascular risk factors associated with excess weight in children and adolescents: the Belo Horizonte heart study].

    Science.gov (United States)

    Ribeiro, Robespierre Q C; Lotufo, Paulo A; Lamounier, Joel A; Oliveira, Reynaldo G; Soares, José Francisco; Botter, Denise Aparecida

    2006-06-01

    To examine the association of overweight and obesity with physical activity, blood pressure (BP) and serum lipid profiles. Epidemiologic investigation of 1,450 students, between the ages of 6 and 18, in the city of Belo Horizonte, MG. weight, height, BP, skinfold thickness, waist circumference, physical activity, total cholesterol (TC), LDL-c, HDL-c, and dietary habits. The prevalence rates for overweight and obesity were 8.4% and 3.1%, respectively. In relation to the students in the lower quartile (Q1) of the distribution of subscapular skinfold, the students in the upper quartile (Q4) presented a 3.7 times higher risk (odds ratio) of having elevated TC levels. Overweight and obese students had a 3.6 times higher risk of having elevated systolic blood pressure, and a 2.7 times higher risk of elevated diastolic blood pressure when compared to normal weight students. The less active students in the Q1 of distribution of MET presented a 3.8 times higher risk of having elevated TC levels compared to those who were more active (Q4). Students who were overweight, obese or in the upper quartiles for other adiposity variables, as well as students with low levels of physical activity or a sedentary lifestyle presented higher blood pressure levels and a lipid profile indicative of an increased risk of developing atherosclerosis.

  5. Relationship of body build and development of pulmonary tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, K.

    1974-01-01

    Height, weight, Body Build Index (relative body weight), sub-scapular skinfold thickness, serum cholesterol level, hemoglobin concentration, and serum uric acid level immediately preceding detection of tuberculosis were compared between index and control cases on 145 pairs, by sex and age group (49 or under and 50 or over). Average height of index cases was greater than that of the control cases. Control cases were heavier than index cases for both sexes and age groups. Comparison of Body Build Index exhibited more distinct differences between the two groups, which were more remarkable in the older age group. Significantly thicker skinfold was demonstrated only among the female control cases. Serum cholesterol and uric acid level were significantly higher among the male control cases. No difference in hemoglobin concentration was observed between the index and control cases. Results not only support previous studies which had shown higher morbidity of tuberculosis among underweight persons, but also suggest that nutritional factors might be important in lowering the susceptibility to development of tuberculosis. (DLC)

  6. Proton Straggling in Thick Silicon Detectors

    Science.gov (United States)

    Selesnick, R. S.; Baker, D. N.; Kanekal, S. G.

    2017-01-01

    Straggling functions for protons in thick silicon radiation detectors are computed by Monte Carlo simulation. Mean energy loss is constrained by the silicon stopping power, providing higher straggling at low energy and probabilities for stopping within the detector volume. By matching the first four moments of simulated energy-loss distributions, straggling functions are approximated by a log-normal distribution that is accurate for Vavilov k is greater than or equal to 0:3. They are verified by comparison to experimental proton data from a charged particle telescope.

  7. Cartilage thickness measurements from optical coherence tomography

    Science.gov (United States)

    Rogowska, Jadwiga; Bryant, Clifford M.; Brezinski, Mark E.

    2003-02-01

    We describe a new semiautomatic image processing method for detecting the cartilage boundaries in optical coherence tomography (OCT). In particular, we focus on rabbit cartilage since this is an important animal model for testing both chondroprotective agents and cartilage repair techniques. The novel boundary-detection system presented here consists of (1) an adaptive filtering technique for image enhancement and speckle reduction, (2) edge detection, and (3) edge linking by graph searching. The procedure requires several steps and can be automated. The quantitative measurements of cartilage thickness on OCT images correlated well with measurements from histology.

  8. Retinal thickness in children with anisohypermetropic amblyopia.

    Science.gov (United States)

    Nishi, Tomo; Ueda, Tetsuo; Hasegawa, Taiji; Miyata, Kimie; Ogata, Nahoko

    2015-08-01

    To determine the thickness of the fovea in eyes of children with anisohypermetropic amblyopia, their fellow eyes and eyes of age-matched controls. Additionally, to assess the effects of optical treatment on the foveal thickness in eyes with anisohypermetropic amblyopia. Twenty-one patients (6.0±2.3 years, mean±SD) with anisohypermetropic amblyopia and 25 age-matched controls (5.6±1.9 years) were studied. Spectral-domain optical coherence tomography (SD-OCT) was used to obtain OCT images. The foveal thickness and the thickness of the outer nuclear layer (ONL), photoreceptor inner segment (IS) layer and outer segment (OS) layer were measured by the embedded OCT software. The length of the OS was significantly greater in the fellow eyes (48.0±6.6 µm) than in the amblyopic eyes (42.4±4.6 µm, p=0.03). One year after the optical treatment of the anisohypermetropia, the best-corrected visual acuity (BCVA) improved and the length of the OS was significantly increased (p=0.0001). After optical treatment, there was no more significant difference in the OS length between the amblyopic eyes and the fellow eyes (p=0.95). The change of BCVA was significantly correlated with the change of the length of the OS 1 year after the treatment (r=0.52; p=0.0004). Anisohypermetropic amblyopic eyes have qualitative and quantitative differences in the retinal microstructures of the fovea from normal eyes. An increase in the OS length was detected in the amblyopic eyes after the optical treatment. A significant correlation was found between the increased OS length and better BCVA. The trial registration number of the internal review board of Nara Medical University was 774. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  9. OPTIMAL THICKNESS OF A CYLINDRICAL SHELL

    Directory of Open Access Journals (Sweden)

    Paul Ziemann

    2015-01-01

    Full Text Available In this paper an optimization problem for a cylindrical shell is discussed. The aim is to look for an optimal thickness of a shell to minimize the deformation under an applied external force. As a side condition, the volume of the shell has to stay constant during the optimization process. The deflection is calculated using an approach from shell theory. The resulting control-to-state operator is investigated analytically and a corresponding optimal control problem is formulated. Moreover, necessary conditions for an optimal solution are stated and numerical solutions are presented for different examples.

  10. Dressings for superficial and partial thickness burns.

    Science.gov (United States)

    Wasiak, Jason; Cleland, Heather; Campbell, Fiona; Spinks, Anneliese

    2013-03-28

    An acute burn wound is a complex and evolving injury. Extensive burns produce systemic consequences, in addition to local tissue damage. Treatment of partial thickness burn wounds is directed towards promoting healing and a wide variety of dressings are currently available. Improvements in technology and advances in understanding of wound healing have driven the development of new dressings. Dressing selection should be based on their effects on healing, but ease of application and removal, dressing change requirements, cost and patient comfort should also be considered. To assess the effects of burn wound dressings on superficial and partial thickness burns. For this first update we searched The Cochrane Wounds Group Specialised Register (searched 8 November 2012); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 10); Ovid MEDLINE (2008 to October Week 4 2012); Ovid MEDLINE (In-Process & Other Non-Indexed Citations, November 07, 2012); Ovid EMBASE (2008 to 2012 Week 44); AND EBSCO CINAHL (1982 to 2 November 2012). All randomised controlled trials (RCTs) that evaluated the effects of burn wound dressings on the healing of superficial and partial thickness burns. Two authors extracted the data independently using standardised forms. We assessed each trial for internal validity and resolved differences by discussion. A total of 30 RCTs are included in this review. Overall both the quality of trial reporting and trial conduct were generally poor and meta analysis was largely precluded due to study heterogeneity or poor data reporting. In the context of this poor quality evidence, silver sulphadiazine (SSD) was consistently associated with poorer healing outcomes than biosynthetic (skin substitute) dressings, silver-containing dressings and silicon-coated dressings. Burns treated with hydrogel dressings appear to heal more quickly than those treated with usual care. There is a paucity of high-quality evidence regarding the

  11. A Note on Asymmetric Thick Branes

    Directory of Open Access Journals (Sweden)

    D. Bazeia

    2014-01-01

    Full Text Available We study asymmetric thick braneworld scenarios, generated after adding a constant to the superpotential associated with the scalar field. We study in particular models with odd and even polynomial superpotentials, and we show that asymmetric brane can be generated irrespective of the potential being symmetric or asymmetric. We study in addition the nonpolynomial sine-Gordon like model, also constructed with the inclusion of a constant in the standard superpotential, and we investigate gravitational stability of the asymmetric brane. The results suggest robustness of the new braneworld scenarios and add further possibilities of the construction of asymmetric branes.

  12. Thickness fluctuations in turbulent soap films.

    Science.gov (United States)

    Greffier, O; Amarouchene, Y; Kellay, H

    2002-05-13

    Rapidly flowing soap films provide a simple and attractive system to study two-dimensional hydrodynamics and turbulence. By measuring the rapid fluctuations of the thickness of the film in the turbulent regime, we find that the statistics of these fluctuations closely resemble those of a passive scalar field in a turbulent flow. The scalar spectra are well described by Kolmogorov-like scaling while the high-order moments show clear deviations from regular scaling just like dye or temperature fluctuations in 3D turbulent flows.

  13. Global anisotropy and the thickness of continents

    Science.gov (United States)

    Gung, Yuancheng; Panning, Mark; Romanowicz, Barbara

    2003-04-01

    For decades there has been a vigorous debate about the depth extent of continental roots. The analysis of heat-flow, mantle-xenolith and electrical-conductivity data all indicate that the coherent, conductive part of continental roots (the `tectosphere') is at most 200-250km thick. Some global seismic tomographic models agree with this estimate, but others suggest that a much thicker zone of high velocities lies beneath continental shields, reaching a depth of at least 400km. Here we show that this disagreement can be reconciled by taking into account seismic anisotropy. We show that significant radial anisotropy, with horizontally polarized shear waves travelling faster than those that are vertically polarized, is present under most cratons in the depth range 250-400km-similar to that found under ocean basins at shallower depths of 80-250km. We propose that, in both cases, the anisotropy is related to shear in a low-viscosity asthenospheric channel, located at different depths under continents and oceans. The seismically defined `tectosphere' is then at most 200-250km thick under old continents. The `Lehmann discontinuity', observed mostly under continents at about 200-250km, and the `Gutenberg discontinuity', observed under oceans at depths of about 60-80km, may both be associated with the bottom of the lithosphere, marking a transition to flow-induced asthenospheric anisotropy.

  14. Reduced orbitofrontal cortical thickness in male adolescents with internet addiction

    National Research Council Canada - National Science Library

    Hong, Soon-Beom; Kim, Jae-Won; Choi, Eun-Jung; Kim, Ho-Hyun; Suh, Jeong-Eun; Kim, Chang-Dai; Klauser, Paul; Whittle, Sarah; Yűcel, Murat; Pantelis, Christos; Yi, Soon-Hyung

    2013-01-01

    .... However, no study to date has examined OFC thickness in internet addiction. In the current study, we investigated the existence of differences in cortical thickness of the OFC in adolescents with internet addiction...

  15. Cortical thickness abnormalities in late adolescence with online gaming addiction

    National Research Council Canada - National Science Library

    Yuan, Kai; Cheng, Ping; Dong, Tao; Bi, Yanzhi; Xing, Lihong; Yu, Dahua; Zhao, Limei; Dong, Minghao; von Deneen, Karen M; Liu, Yijun; Qin, Wei; Tian, Jie

    2013-01-01

    ...) and age-, education- and gender-matched controls (n = 18) were acquired. The cortical thickness measurement method was employed to investigate alterations of cortical thickness in individuals with online gaming addiction...

  16. Subcutaneous and segmental fat loss with and without supportive supplements in conjunction with a low-calorie high protein diet in healthy women.

    Science.gov (United States)

    Falcone, Paul H; Tai, Chih Yin; Carson, Laura R; Joy, Jordan M; Mosman, Matt M; Vogel, Roxanne M; McCann, Tyler R; Crona, Kevin P; Griffin, J Daniel; Kim, Michael P; Moon, Jordan R

    2015-01-01

    Weight loss benefits of multi-ingredient supplements in conjunction with a low-calorie, high-protein diet in young women are unknown. Therefore, the purpose of this study was to investigate the effects of a three-week low-calorie diet with and without supplementation on body composition. Thirty-seven recreationally-trained women (n = 37; age = 27.1 ± 4.2; height = 165.1 ± 6.4; weight = 68.5 ± 10.1; BMI = 25.1 ± 3.4) completed one of the following three-week interventions: no change in diet (CON); a high-protein, low-calorie diet supplemented with a thermogenic, conjugated linoleic acid (CLA), a protein gel, and a multi-vitamin (SUP); or the high-protein diet with isocaloric placebo supplements (PLA). Before and after the three-week intervention, body weight, %Fat via dual X-ray absorptiometry (DXA), segmental fat mass via DXA, %Fat via skinfolds, and skinfold thicknesses at seven sites were measured. SUP and PLA significantly decreased body weight (SUP: PRE, 70.47 ± 8.01 kg to POST, 67.51 ± 8.10 kg; PLA: PRE, 67.88 ± 12.28 kg vs. POST, 66.38 ± 11.94 kg; p ≤ 0.05) with a greater (p ≤ 0.05) decrease in SUP than PLA or CON. SUP and PLA significantly decreased %Fat according to DXA (SUP: PRE, 34.98 ± 7.05% to POST, 32.99 ± 6.89%; PLA: PRE, 34.22 ± 6.36% vs. POST, 32.69 ± 5.84%; p ≤ 0.05), whereas only SUP significantly decreased %Fat according to skinfolds (SUP: PRE, 27.40 ± 4.09% to POST, 24.08 ± 4.31%; p ≤ 0.05). SUP significantly (p ≤ 0.05) decreased thicknesses at five skinfolds (chest, waist, hip, subscapular, and tricep) compared to PLA, but not at two skinfolds (axilla and thigh). The addition of a thermogenic, CLA, protein, and a multi-vitamin to a three-week low-calorie diet improved weight loss, total fat loss and subcutaneous fat loss, compared to diet alone.

  17. High performance PZT thick film actuators using in plane polarisation

    OpenAIRE

    Ernst, Dörthe; Bramlage, Bernhard; Gebhardt, Sylvia; Schönecker, Andreas

    2015-01-01

    Piezoceramic thick films offer the possibility of integrated functional components in planar design. They can be applied as sensors, actuators, ultrasonic transducers, transformers and generators. Typically, piezoceramic thick films are excited through the film thickness. In contrast, in-plane mode of excitation will be beneficial especially for actuator applications. The use of interdigitated electrodes (IDEs) enables in-plane excitation of piezoceramic thick films. Actuator performance of c...

  18. THE EFFECT OF PROCESS PARAMETERS ON THICKNESS DISTRIBUTION IN THERMOFORMING

    Directory of Open Access Journals (Sweden)

    Olcay Eksi

    2017-06-01

    Full Text Available In this study, cylindrical, conical and hemispherical molds were used to form flat thermoplastic sheets which are 1.5 mm in thickness. The effect of plug assist on thickness distribution was investigated. The sheets were formed with and without plug assist. Then thickness distributions on thermoformed products were obtained for two experimental procedures by a digital caliper (Resolution: 0.01mm. As a result, plug assist thermoforming provides more uniform thickness distributions than negative forming.

  19. Reduced cortical thickness in gambling disorder

    DEFF Research Database (Denmark)

    Grant, Jon E; Odlaug, Brian Lawrence; Chamberlain, Samuel R

    2015-01-01

    Gambling disorder has recently been recognized as a prototype 'behavioral addiction' by virtue of its inclusion in the DSM-5 category of 'Substance-Related and Addictive Disorders.' Despite its newly acquired status and prevalence rate of 1-3 % globally, relatively little is known regarding...... the neurobiology of this disorder. The aim of this study was to explore cortical morphometry in untreated gambling disorder, for the first time. Subjects with gambling disorder (N = 16) free from current psychotropic medication or psychiatric comorbidities, and healthy controls (N = 17), were entered...... into the study and undertook magnetic resonance imaging (3T MRI). Cortical thickness was quantified using automated segmentation techniques (FreeSurfer), and group differences were identified using permutation cluster analysis, with stringent correction for multiple comparisons. Gambling disorder was associated...

  20. Tensile Instability in a Thick Elastic Body

    Science.gov (United States)

    Overvelde, Johannes; Dykstra, David; de Rooij, Rijk; Bertoldi, Katia

    A range of instabilities can occur in soft bodies that undergo large deformation. While most of them arise under compressive forces, it has previously been shown analytically that a tensile instability can occur in an elastic block subjected to equitriaxial tension. Guided by this result, we conducted centimeter-scale experiments on thick elastomeric samples under generalized plane strain conditions and observed for the first time this elastic tensile instability. We found that equibiaxial stretching leads to the formation of a wavy pattern, as regions of the sample alternatively flatten and extend in the out-of-plane direction. Our work uncovers a new type of instability that can be triggered in elastic bodies, enlarging the design space for smart structures that harness instabilities to enhance their functionality.

  1. Dynamic laser piercing of thick section metals

    Science.gov (United States)

    Pocorni, Jetro; Powell, John; Frostevarg, Jan; Kaplan, Alexander F. H.

    2018-01-01

    Before a contour can be laser cut the laser first needs to pierce the material. The time taken to achieve piercing should be minimised to optimise productivity. One important aspect of laser piercing is the reliability of the process because industrial laser cutting machines are programmed for the minimum reliable pierce time. In this work piercing experiments were carried out in 15 mm thick stainless steel sheets, comparing a stationary laser and a laser which moves along a circular trajectory with varying processing speeds. Results show that circular piercing can decrease the pierce duration by almost half compared to stationary piercing. High speed imaging (HSI) was employed during the piercing process to understand melt behaviour inside the pierce hole. HSI videos show that circular rotation of the laser beam forces melt to eject in opposite direction of the beam movement, while in stationary piercing the melt ejects less efficiently in random directions out of the hole.

  2. On thick domain walls in general relativity

    Science.gov (United States)

    Goetz, Guenter; Noetzold, Dirk

    1989-01-01

    Planar scalar field configurations in general relativity differ considerably from those in flat space. It is shown that static domain walls of finite thickness in curved space-time do not possess a reflection symmetry. At infinity, the space-time tends to the Taub vacuum on one side of the wall and to the Minkowski vacuum (Rindler space-time) on the other. Massive test particles are always accelerated towards the Minkowski side, i.e., domain walls are attractive on the Taub side, but repulsive on the Minkowski side (Taub-vacuum cleaner). It is also proved that the pressure in all directions is always negative. Finally, a brief comment is made concerning the possibility of infinite, i.e., bigger than horizon size, domain walls in our universe. All of the results are independent of the form of the potential V(phi) greater than or equal to 0 of the scalar field phi.

  3. Through thick and thin : Structure of the Galactic thick disc from extragalactic surveys

    NARCIS (Netherlands)

    Kordopatis, G.; Hill, V.; Irwin, M.; Gilmore, G.; Wyse, R. F. G.; Tolstoy, E.; de Laverny, P.; Recio-Blanco, A.; Battaglia, G.; Starkenburg, E.

    Context. We aim to understand the accretion history of the Milky Way by exploring the vertical and radial properties of the Galactic thick disc. Aims. We study the chemical and kinematic properties of roughly a thousand spectra of faint magnitude foreground Galactic stars observed serendipitously

  4. Retinal and choroidal thickness in myopic anisometropia.

    Science.gov (United States)

    Vincent, Stephen J; Collins, Michael J; Read, Scott A; Carney, Leo G

    2013-04-03

    We compared the retinal thickness (RT) and choroidal thickness (ChT) between the fellow eyes of nonamblyopic myopic anisometropes. The eyes of 22 nonamblyopic myopic anisometropes (≥ 1 diopter [D] spherical equivalent refraction [SER] anisometropia) were examined using spectral domain optical coherence tomography (SD-OCT). Customized software was used to register, align, and average multiple foveal OCT B-scan images from each subject to enhance image quality. Two independent masked observers manually determined the RT and ChT from each SD-OCT image up to 2.5 mm nasal and temporal to the fovea. Axial length (AXL) was measured using optical low coherence biometry during relaxed accommodation. The mean SER anisometropia was 1.74 ± 0.95 D and the mean interocular AXL difference was 0.58 ± 0.41 mm. There was no significant difference in foveal RT between the fellow eyes (P > 0.05). Mean subfoveal ChT was significantly thinner in the more myopic eye (252 ± 46 μm) compared to the fellow, less myopic eye (286 ± 58 μm) (P < 0.001). There was a moderate correlation between the interocular difference in subfoveal ChT and the interocular difference in AXL (r = -0.50, P < 0.01). Asian anisometropes displayed more regionally symmetrical (nasal-temporal) interocular differences in ChT profile compared to Caucasians. RT was similar between the fellow eyes of myopic anisometropes; however, the subfoveal choroid was significantly thinner in the more myopic (longer) eye of this anisometropic cohort. The interocular asymmetry in ChT correlated with the interocular difference in AXL.

  5. Latitudinal variation of ionospheric slab thickness

    Science.gov (United States)

    Gulyaeva, T. L.; Jayachandran, B.; Krishnankutty, T. N.

    The ionospheric slab thickness τ, defined as a ratio of the total electron content (TEC) to the F-region peak electron density NmF2, is a first order measure of the shape of the electron density profile. In the present study, we use GPS-derived TEC and vertical electron content estimates ITEC from ground-based ionosonde observations together with the corresponding foF2 (F2 layer critical frequency) and hmF2 (F2 layer peak height) at 14 world-wide stations lying at different latitude regions from the geomagnetic equator to north pole. The period of study is during 2001-2002, which is close to the solar maximum phase of the 23rd solar cycle. Hourly values of TEC, ITEC, foF2, hmF2 and τ during the period of study are used to compare τ values from the observation and model predictions using the International Reference Ionosphere extended towards the plasmapause with the plasmasphere option of the Russian standard model of the ionosphere, IRI*. For the three latitudinal zones (high, mid and low latitudes) the IRI* predictions of τ are compared with observed τ values for the bottomside ionosphere (below hmF2), topside ionosphere (between hmF2 and 1000 km), plasmasphere (from 1000 to 20,000 km), and the total height range through the ionosphere and plasmasphere. Significant overestimation of τ has been revealed when using IRI*, particularly for the topside ionosphere at high latitudes. Relation of the topside part of slab thickness with the topside half peak density height above the F2 layer peak provides new characteristic parameter for modeling of the topside shape of electron density profile.

  6. Cladding Attachment Over Thick Exterior Insulating Sheathing

    Energy Technology Data Exchange (ETDEWEB)

    Baker, P. [Building Science Corporation, Somerville, MA (United States); Eng, P. [Building Science Corporation, Somerville, MA (United States); Lepage, R. [Building Science Corporation, Somerville, MA (United States)

    2014-01-01

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1. What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2. Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3. What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

  7. Cladding Attachment Over Thick Exterior Insulating Sheathing

    Energy Technology Data Exchange (ETDEWEB)

    Baker, P. [Building Science Corporation, Somerville, MA (United States); Eng, P. [Building Science Corporation, Somerville, MA (United States); Lepage, R. [Building Science Corporation, Somerville, MA (United States)

    2014-01-01

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1.What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2.Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3.What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

  8. Spherically symmetric thick branes cosmological evolution

    Science.gov (United States)

    Bernardini, A. E.; Cavalcanti, R. T.; da Rocha, Roldão

    2015-01-01

    Spherically symmetric time-dependent solutions for the 5D system of a scalar field canonically coupled to gravity are obtained and identified as an extension of recent results obtained by Ahmed et al. (JHEP 1404:061. arXiv:1312.3576 [hep-th], 2014). The corresponding cosmology of models with regularized branes generated by such a 5D scalar field scenario is also investigated. It has been shown that the anisotropic evolution of the warp factor and consequently the Hubble like parameter are both driven by the radial coordinate on the brane, which leads to an emergent thick brane-world scenario with spherically symmetric time dependent warp factor. Meanwhile, the separability of variables depending on fifth dimension, , which is exhibited by the equations of motion, allows one to recover the extra dimensional profiles obtained in Ahmed et al. (2014), namely the extra dimensional part of the scale (warp) factor and the scalar field dependence on . Therefore, our results are mainly concerned with the time dependence of a spherically symmetric warp factor. Besides evincing possibilities for obtaining asymmetric stable brane-world scenarios, the extra dimensional profiles here obtained can also be reduced to those ones investigated in Ahmed et al. (2014).

  9. How accurate are estimates of glacier ice thickness? Results from ITMIX, the Ice Thickness Models Intercomparison eXperiment

    DEFF Research Database (Denmark)

    Farinotti, Daniel; Brinkerhoff, Douglas J.; Clarke, Garry K. C.

    2017-01-01

    Knowledge of the ice thickness distribution of glaciers and ice caps is an important prerequisite for many glaciological and hydrological investigations. A wealth of approaches has recently been presented for inferring ice thickness from characteristics of the surface. With the Ice Thickness Models...... Intercomparison eXperiment (ITMIX) we performed the first coordinated assessment quantifying individual model performance. A set of 17 different models showed that individual ice thickness estimates can differ considerably - locally by a spread comparable to the observed thickness. Averaging the results...... of multiple models, however, significantly improved the results: on average over the 21 considered test cases, comparison against direct ice thickness measurements revealed deviations on the order of 10 +/- 24% of the mean ice thickness (1 sigma estimate). Models relying on multiple data sets...

  10. Fracture resistance of monolithic zirconia molar crowns with reduced thickness.

    Science.gov (United States)

    Nakamura, Keisuke; Harada, Akio; Inagaki, Ryoichi; Kanno, Taro; Niwano, Yoshimi; Milleding, Percy; Örtengren, Ulf

    2015-01-01

    The purpose of the present study was to analyze the relationship between fracture load of monolithic zirconia crowns and axial/occlusal thickness and to evaluate the fracture resistance of monolithic zirconia crowns with reduced thickness in comparison with that of monolithic lithium disilicate crowns with regular thickness. Monolithic zirconia crowns (Lava Plus Zirconia, 3M/ESPE) with specified axial/occlusal thicknesses and lithium disilicate crowns (IPS e.max press, Ivoclar/Vivadent) with regular thickness were fabricated using a dental CAD/CAM system and a press technique, respectively. The crowns cemented onto dies were loaded until fracture. Based on measurements of the crown thickness made by micro-CT and the fracture load, multiple regression analysis was performed. It was revealed that the occlusal thickness significantly affected the fracture load (p zirconia crowns, the fracture load of the zirconia crowns with the occlusal thickness of 0.5 mm (5558 ± 522 N) was significantly higher than that of lithium disilicate crowns with an occlusal thickness of 1.5 mm (3147 ± 409 N). Within the limitations of the present study, it is suggested that monolithic zirconia crown with chamfer width of 0.5 mm and occlusal thickness of 0.5 mm can be used in the molar region in terms of fracture resistance.

  11. The effect of eggshell thickness on hatchability of quail eggs.

    Science.gov (United States)

    Ergun, Oguz Fatih; Yamak, Umut Sami

    2017-09-01

    The aim of the successful incubation period is to achieve maximum health chicks in each batch. Therefore, all factors affecting incubation have to be investigated in detail. This study investigated the effect of eggshell thickness on hatchability of quail eggs. A total of 1415 eggs were collected from the same flock at the ages of 23 and 41 weeks. Two different incubations were performed at these eggs. Eggshell thicknesses of all eggs were determined with an ultrasonic gauge before incubation. Incubation period was applied as for 18 days. After 15 days of incubation, eggs were transferred to hatching machine. Eggs were classified as thin-, medium-, and thick-shelled according to eggshell thickness values. Eggshell thicknesses were ranged between 0.24 and 0.36 mm, and the differences between the hatching rates of thickness values were not found significant. Hatchability of thin-, medium-, and thick-shelled eggs was found as 69.2%, 69.4%, and 82.4% for Experiment 1. These values were as 87.8%, 89.2%, and 91.9% for Experiment 2, respectively. Similar to eggshell thickness frequencies, the differences between hatching rates of eggshell thickness groups were found insignificant. Results of this study showed that eggshell thickness does not affect hatchability.

  12. Changes in cortical volumetric bone mineral density and thickness, and trabecular thickness in lactating women postpartum.

    Science.gov (United States)

    Brembeck, P; Lorentzon, M; Ohlsson, C; Winkvist, A; Augustin, H

    2015-02-01

    Lactation is associated with decreased areal bone mineral density (aBMD). Replenishment occurs especially after ceased lactation. Changes in volumetric bone mineral density (vBMD), microstructure, and dimensional parameters are unknown and may clarify the role of lactation for skeletal health. OBJECTIVE AND MAIN OUTCOMES: The objective of the study was to test the hypothesis that lactation is associated with changes in aBMD, vBMD, microstructure, and dimensional parameters. At baseline (0.5 mo after delivery) and 4, 12, and 18 months thereafter, bone was assessed using dual-energy x-ray absorptiometry and high-resolution peripheral quantitative computed tomography. Eighty-one fair-skinned postpartum women and 21 controls aged 25-40 years were recruited. The completion ratio was 73%. Postpartum women were categorized depending on duration of lactation: 0-3.9, 4-8.9, and 9 months or longer. During the first 4 months, aBMD decreased at several sites (geometric mean ± SE; -0.73% ± 0.21% to -3.98% ± 0.76%) in women lactating at least 4 months. During the same time, cortical vBMD at the ultradistal tibia decreased in women lactating 4-8.9 months (-0.26% ± 0.08%) and 9 months or longer (-0.49% ± 0.10%). At 12 months postpartum, cortical thickness (≥ 9 mo, -2.48% ± 0.41%) and trabecular thickness (4-8.9 mo, -2.14% ± 0.92%; ≥ 9 mo, -2.56% ± 1.21%) also were lower than baseline. No decreases were found in women lactating less than 4 months or in controls in these parameters. At 18 months postpartum, both cortical vBMD (≥ 9 mo, -0.77% ± 0.17%) and trabecular thickness (4-8.9 mo, -2.25% ± 1.25%; ≥ 9 mo, -3.21% ± 1.41%) were lower in women with long lactation. Decreases in cortical vBMD, thickness, and trabecular thickness at the ultradistal tibia were found in women lactating 4 months or longer. Longer follow-up is needed to confirm whether women with extended lactation recover fully or whether the changes could potentially lead to an increased risk of

  13. Multiple High Voltage Pulse Stressing of Polymer Thick Film Resistors

    Directory of Open Access Journals (Sweden)

    Busi Rambabu

    2014-01-01

    Full Text Available The purpose of this paper is to study high voltage interactions in polymer thick film resistors, namely, polyvinyl chloride- (PVC- graphite thick film resistors, and their applications in universal trimming of these resistors. High voltages in the form of impulses for various pulse durations and with different amplitudes have been applied to polymer thick film resistors and we observed the variation of resistance of these resistors with high voltages. It has been found that the resistance of polymer thick film resistors decreases in the case of higher resistivity materials and the resistance of polymer thick film resistor increases in the case of lower resistivity materials when high voltage impulses are applied to them. It has been also found that multiple high voltage pulse (MHVP stressing can be used to trim the polymer thick film resistors either upwards or downwards.

  14. Thickness Dependent on Photocatalytic Activity of Hematite Thin Films

    OpenAIRE

    Chen, Yen-Hua; Tu, Kuo-Jui

    2012-01-01

    Hematite (Fe2O3) thin films with different thicknesses are fabricated by the rf magnetron sputtering deposition. The effects of film thicknesses on the photocatalytic activity of hematite films have been investigated. Hematite films possess a polycrystalline hexagonal structure, and the band gap decreases with an increase of film thickness. Moreover, all hematite films exhibit good photocatalytic ability under visible-light irradiation; the photocatalytic activity of hematite films increases ...

  15. THz metal mesh filters on electrically thick fused silica substrates

    OpenAIRE

    Otter, WJ; F. Hu; Hazell, JF; Lucyszyn, S

    2014-01-01

    ? 2014 IEEE.This paper shows simulated and measured results of ultra-low cost metal mesh filters on electrically thick substrates for millimeter-wave and THz bands. It provides a broad overview of metal mesh filters currently available and suggest why it is worth moving to an electrically thick substrate for ultra-low cost applications. We demonstrate scalable traditional metal mesh filters on 525 ?m thick fused silica substrates. In addition, trapped-mode excitation is exploited to improve o...

  16. Measurements of adiposity and high blood pressure among children and adolescents living in Belo Horizonte.

    Science.gov (United States)

    Ribeiro, Robespierre C; Lamounier, Joel A; Oliveira, Reynaldo G; Bensenor, Isabela M; Lotufo, Paulo A

    2009-09-01

    To verify an association, if it exists, between obesity and blood pressure raised beyond the 90th percentile in children and adolescents, and to determine the measure of adiposity that best correlates with blood pressure in these subjects. Cross-sectional study. A school-based study in Belo Horizonte, Brazil. We selected randomly 1,403 students, aged from 6 to 18 years, from 545,046 students attending 521 public and private schools. Those selected completed the study. MAIN MEASURES OF OUTCOME: We recorded the weight, height, skin fold in the triceps, subscapular, and suprailiac areas, waist and hip circumference, body-mass index, and resting systolic and diastolic blood pressures using a mercury sphygmomanometer. In univariate analyses, body mass index greater or lesser than 85th percentile, measurements of skin thickness in the subscapular and suprailiac areas, and the sum of all measurements of skinfold thickness, were associated with both systolic and diastolic measurements of blood pressure. After multivariate analyses that adjusted for all measurements of adiposity except itself, and age, race, and socioeconomic state, we found that the increased body mass index was associated with a 3.6-fold increased frequency of elevated systolic measurements of blood pressure, with 95% confidence intervals from 2.2 to 5.8, and a 2.7-fold increased frequency of elevated measurements of diastolic blood pressure, with 95% confidence intervals from 1.9 to 4.0. Body-mass index serves as a better predictor of elevated blood pressure among children than do local measurements of adiposity.

  17. Inline hyperspectral thickness determination of thin films using neural networks

    Science.gov (United States)

    Tremmel, Anton J.; Weiss, Roman; Schardt, Michael; Koch, Alexander W.

    2017-04-01

    Combining reflectometry and hyperspectral imaging allows mapping of thin film thickness. Therefore, layer thickness is calculated by comparing a dataset of simulated spectra with the measured data. Utilizing the maximum frame rate of the hyperspectral imager, the pixel wise spectra comparing procedure cannot be performed using a standard computer due to the processing load. In this work, a method using neural networks for calculating layer thickness is presented. By the use of the nonlinear equation as result of a trained neural network, thickness data can be determined with a measurement rate matching the maximum frame rate of the hyperspectral imager.

  18. Ultrasonic metal sheet thickness measurement without prior wave speed calibration

    Science.gov (United States)

    Dixon, S.; Petcher, P. A.; Fan, Y.; Maisey, D.; Nickolds, P.

    2013-11-01

    Conventional ultrasonic mensuration of sample thickness from one side only requires the bulk wave reverberation time and a calibration speed. This speed changes with temperature, stress, and microstructure, limiting thickness measurement accuracy. Often, only one side of a sample is accessible, making in situ calibration impossible. Non-contact ultrasound can generate multiple shear horizontal guided wave modes on one side of a metal plate. Measuring propagation times of each mode at different transducer separations, allows sheet thickness to be calculated to better than 1% accuracy for sheets of at least 1.5 mm thickness, without any calibration.

  19. Oxygen Sensing Properties of the WO3 Thick Films

    Directory of Open Access Journals (Sweden)

    R. S. KHADAYATE

    2009-08-01

    Full Text Available This paper presents oxygen gas sensing properties of WO3 thick films. In this work, the WO3 thick films were prepared by standard screen-printing method. These films were characterized by X-ray diffraction (XRD measurements and scanning electron microscopy (SEM. The oxygen gas sensing properties of these thick films were investigated at different operating temperatures and oxygen gas concentrations. The WO3 thick films exhibit excellent oxygen sensing properties with a maximum sensitivity of ~ 35.75 % at 350 oC in air atmosphere with fast response and recovery time.

  20. Cortical Thickness Abnormalities in Late Adolescence with Online Gaming Addiction

    Science.gov (United States)

    Yuan, Kai; Cheng, Ping; Dong, Tao; Bi, Yanzhi; Xing, Lihong; Yu, Dahua; Zhao, Limei; Dong, Minghao; von Deneen, Karen M.; Liu, Yijun; Qin, Wei; Tian, Jie

    2013-01-01

    Online gaming addiction, as the most popular subtype of Internet addiction, had gained more and more attention from the whole world. However, the structural differences in cortical thickness of the brain between adolescents with online gaming addiction and healthy controls are not well unknown; neither was its association with the impaired cognitive control ability. High-resolution magnetic resonance imaging scans from late adolescence with online gaming addiction (n = 18) and age-, education- and gender-matched controls (n = 18) were acquired. The cortical thickness measurement method was employed to investigate alterations of cortical thickness in individuals with online gaming addiction. The color-word Stroop task was employed to investigate the functional implications of the cortical thickness abnormalities. Imaging data revealed increased cortical thickness in the left precentral cortex, precuneus, middle frontal cortex, inferior temporal and middle temporal cortices in late adolescence with online gaming addiction; meanwhile, the cortical thicknesses of the left lateral orbitofrontal cortex (OFC), insula, lingual gyrus, the right postcentral gyrus, entorhinal cortex and inferior parietal cortex were decreased. Correlation analysis demonstrated that the cortical thicknesses of the left precentral cortex, precuneus and lingual gyrus correlated with duration of online gaming addiction and the cortical thickness of the OFC correlated with the impaired task performance during the color-word Stroop task in adolescents with online gaming addiction. The findings in the current study suggested that the cortical thickness abnormalities of these regions may be implicated in the underlying pathophysiology of online gaming addiction. PMID:23326379

  1. Cortical thickness abnormalities in late adolescence with online gaming addiction.

    Science.gov (United States)

    Yuan, Kai; Cheng, Ping; Dong, Tao; Bi, Yanzhi; Xing, Lihong; Yu, Dahua; Zhao, Limei; Dong, Minghao; von Deneen, Karen M; Liu, Yijun; Qin, Wei; Tian, Jie

    2013-01-01

    Online gaming addiction, as the most popular subtype of Internet addiction, had gained more and more attention from the whole world. However, the structural differences in cortical thickness of the brain between adolescents with online gaming addiction and healthy controls are not well unknown; neither was its association with the impaired cognitive control ability. High-resolution magnetic resonance imaging scans from late adolescence with online gaming addiction (n = 18) and age-, education- and gender-matched controls (n = 18) were acquired. The cortical thickness measurement method was employed to investigate alterations of cortical thickness in individuals with online gaming addiction. The color-word Stroop task was employed to investigate the functional implications of the cortical thickness abnormalities. Imaging data revealed increased cortical thickness in the left precentral cortex, precuneus, middle frontal cortex, inferior temporal and middle temporal cortices in late adolescence with online gaming addiction; meanwhile, the cortical thicknesses of the left lateral orbitofrontal cortex (OFC), insula, lingual gyrus, the right postcentral gyrus, entorhinal cortex and inferior parietal cortex were decreased. Correlation analysis demonstrated that the cortical thicknesses of the left precentral cortex, precuneus and lingual gyrus correlated with duration of online gaming addiction and the cortical thickness of the OFC correlated with the impaired task performance during the color-word Stroop task in adolescents with online gaming addiction. The findings in the current study suggested that the cortical thickness abnormalities of these regions may be implicated in the underlying pathophysiology of online gaming addiction.

  2. Cortical thickness abnormalities in late adolescence with online gaming addiction.

    Directory of Open Access Journals (Sweden)

    Kai Yuan

    Full Text Available Online gaming addiction, as the most popular subtype of Internet addiction, had gained more and more attention from the whole world. However, the structural differences in cortical thickness of the brain between adolescents with online gaming addiction and healthy controls are not well unknown; neither was its association with the impaired cognitive control ability. High-resolution magnetic resonance imaging scans from late adolescence with online gaming addiction (n = 18 and age-, education- and gender-matched controls (n = 18 were acquired. The cortical thickness measurement method was employed to investigate alterations of cortical thickness in individuals with online gaming addiction. The color-word Stroop task was employed to investigate the functional implications of the cortical thickness abnormalities. Imaging data revealed increased cortical thickness in the left precentral cortex, precuneus, middle frontal cortex, inferior temporal and middle temporal cortices in late adolescence with online gaming addiction; meanwhile, the cortical thicknesses of the left lateral orbitofrontal cortex (OFC, insula, lingual gyrus, the right postcentral gyrus, entorhinal cortex and inferior parietal cortex were decreased. Correlation analysis demonstrated that the cortical thicknesses of the left precentral cortex, precuneus and lingual gyrus correlated with duration of online gaming addiction and the cortical thickness of the OFC correlated with the impaired task performance during the color-word Stroop task in adolescents with online gaming addiction. The findings in the current study suggested that the cortical thickness abnormalities of these regions may be implicated in the underlying pathophysiology of online gaming addiction.

  3. A study of compressed breast thickness at Hirosaki University Hospital

    Energy Technology Data Exchange (ETDEWEB)

    Kon, Masanori; Osanai, Tsunemi; Ootani, Yuhiko; Sugawara, Kaoru; Abe, Katsumi [Hirosaki Univ., Aomori (Japan). Hospital

    2000-05-01

    Evaluation of image quality and medical exposure dose is very important in mammography. However, the standard compressed breast thickness of Japanese women is uncertain. Authors therefore analyzed compressed breast thickness on bilateral cephalocaudal and mediolateral oblique radiographs of 3445 women who underwent mammography between June 5, 1989 and December 7, 1998. The total average compressed breast thickness was about 10 mm less than the thickness of the American College of Radiography (ACR) standard mammographic accreditation phantom. It therefore appears necessary to establish a Japanese standard for the phantom to evaluate image quality and medical exposure dose accurately in Japanese women. (K.H.)

  4. The AMBRE project: The thick thin disk and thin thick disk of the Milky Way

    Science.gov (United States)

    Hayden, M. R.; Recio-Blanco, A.; de Laverny, P.; Mikolaitis, S.; Worley, C. C.

    2017-11-01

    We analyze 494 main sequence turnoff and subgiant stars from the AMBRE:HARPS survey. These stars have accurate astrometric information from Gaia DR1, providing reliable age estimates with relative uncertainties of ±1 or 2 Gyr and allowing precise orbital determinations. The sample is split based on chemistry into a low-[Mg/Fe] sequence, which are often identified as thin disk stellar populations, and high-[Mg/Fe] sequence, which are often associated with thick disk stellar populations. We find that the high-[Mg/Fe] chemical sequence has extended star formation for several Gyr and is coeval with the oldest stars of the low-[Mg/Fe] chemical sequence: both the low- and high-[Mg/Fe] sequences were forming stars at the same time. We find that the high-[Mg/Fe] stellar populations are only vertically extended for the oldest, most-metal poor and highest [Mg/Fe] stars. When comparing vertical velocity dispersion for the low- and high-[Mg/Fe] sequences, the high-[Mg/Fe] sequence has lower vertical velocity dispersion than the low-[Mg/Fe] sequence for stars of similar age. This means that identifying either group as thin or thick disk based on chemistry is misleading. The stars belonging to the high-[Mg/Fe] sequence have perigalacticons that originate in the inner disk, while the perigalacticons of stars on the low-[Mg/Fe] sequence are generally around the solar neighborhood. From the orbital properties of the stars, the high-[Mg/Fe] and low-[Mg/Fe] sequences are most likely a reflection of the chemical enrichment history of the inner and outer disk populations, respectively; radial mixing causes both populations to be observed in situ at the solar position. Based on these results, we emphasize that it is important to be clear in defining what populations are being referenced when using the terms thin and thick disk, and that ideally the term thick disk should be reserved for purely geometric definitions to avoid confusion and be consistent with definitions in external

  5. A Semi-Analytical Solution for Elastic Analysis of Rotating Thick Cylindrical Shells with Variable Thickness Using Disk Form Multilayers

    Directory of Open Access Journals (Sweden)

    Mohammad Zamani Nejad

    2014-01-01

    Full Text Available Using disk form multilayers, a semi-analytical solution has been derived for determination of displacements and stresses in a rotating cylindrical shell with variable thickness under uniform pressure. The thick cylinder is divided into disk form layers form with their thickness corresponding to the thickness of the cylinder. Due to the existence of shear stress in the thick cylindrical shell with variable thickness, the equations governing disk layers are obtained based on first-order shear deformation theory (FSDT. These equations are in the form of a set of general differential equations. Given that the cylinder is divided into n disks, n sets of differential equations are obtained. The solution of this set of equations, applying the boundary conditions and continuity conditions between the layers, yields displacements and stresses. A numerical solution using finite element method (FEM is also presented and good agreement was found.

  6. Associação entre espessura da pele e densidade óssea em mulheres adultas Association between skin thickness and bone density in adult women

    Directory of Open Access Journals (Sweden)

    Patrícia de Paula Yoneda

    2011-10-01

    Full Text Available FUNDAMENTOS: Osteoporose acomete principalmente mulheres em menopausa e idosos, predispondo a fraturas que geram morbidade, mortalidade e custos ao sistema de saúde. Como o colágeno dérmico diminui paralelamente à redução da massa óssea com o envelhecimento, a medida da espessura da pele pode ser indício do risco de osteoporose. OBJETIVOS: Avaliar a correlação entre densidade óssea e espessura da pele do dorso das mãos de mulheres adultas. MÉTODOS: Estudo transversal envolvendo mulheres adultas atendidas em ambulatório de hospital universitário submetidas à densitometria óssea, que foram avaliadas individualmente e mensurada, por paquímetro, a espessura da pele no dorso das mãos, além de investigados demais fatores de risco para osteoporose. RESULTADOS: Avaliaram-se 140 pacientes. A média (±dp de idade foi de 57 (±11 anos; a média da espessura da pele do dorso das mãos foi de 1,4 (±0,4 mm. Houve correlação entre as medidas das mãos direita e esquerda (R=0,9; pBACKGROUND: Osteoporosis mainly affects menopausal women and the elderly, predisposing these individuals to fractures that result in morbidity, mortality and costs to the healthcare system. Since dermal collagen reduces in parallel with a decrease in bone mass with aging, skin thickness may be indicative of a risk of osteoporosis. OBJECTIVES: To evaluate the correlation between bone density and skin thickness on the backs of the hands of adult women. METHODS: A cross sectional study involving adult women attending a university hospital outpatient clinic who were interviewed individually and submitted to bone densitometry and measurement of skin thickness on the backs of their hands using skinfold calipers. Other risk factors for osteoporosis were also investigated. RESULTS: A total of 140 patients were evaluated. Mean age (± standard deviation was 57 ± 11 years. Mean skin thickness on the backs of the hands was 1.4 ± 0.4 mm. There was a correlation between

  7. Relationship between leukoaraiosis, carotid intima-media thickness and intima-media thickness variability: Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Lucatelli, Pierleone [University of Rome la Sapienza, Department of Radiology, Rome (Italy); Raz, Eytan [New York University Langone Medical Center, Department of Radiology, New York, NY (United States); Saba, Luca [Azienda Ospedaliero Universitaria, Department of Radiology, di Cagliari - Polo di Monserrato, Cagliari (Italy); Argiolas, Giovanni Maria; Siotto, Paolo [Azienda Ospedaliera Brotzu, Department of Radiology, Cagliari (Italy); Montisci, Roberto [Azienda Ospedaliero Universitaria, Department of Vascular Surgery, di Cagliari - Polo di Monserrato, Cagliari (Italy); Wintermark, Max [University of Virginia, Department of Radiology, Neuroradiology Division, 1215 Lee Street-New Hospital, PO Box 800170, Charlottesville, VA (United States); King, Kevin S. [University of Texas Southwestern Medical Center, Department of Radiology, Dallas, TX (United States); Molinari, Filippo [Politecnico di Torino, Biolab, Department of Electronics, Torino (Italy); Ikeda, Nobutaka [Toho University Ohashi Medical Center, Division of Cardiovascular Medicine, Tokyo (Japan); Suri, Jasjit S. [AtheroPoint trademark LLC, Diagnostic and Monitoring Division, Roseville, CA (United States); University of Idaho, Department of Electrical Engineering, Pocatello, ID (United States)

    2016-12-15

    To assess the relationship between the degree of leukoaraiosis (LA), carotid intima-media thickness (IMT) and intima-media thickness variability (IMTV). Sixty-one consecutive patients, who underwent a brain MRI examination and a carotid artery ultrasound, were included in this retrospective study, which conformed with the Declaration of Helsinki. Written informed consent was waived. In each patient, right/left carotid arteries and brain hemispheres were assessed using automated software for IMT, IMTV and LA volume. The mean hemispheric LA volume was 2,224 mm{sup 3} (SD 2,702 mm{sup 3}) and there was no statistically significant difference in LA volume between the right and left hemispheres (p value = 0.628). The mean IMT and IMTV values were 0.866 mm (SD 0.170) and 0.143 mm (SD 0.100), respectively, without significant differences between the right and left sides (p values 0.733 and 0.098, respectively). The correlation coefficient between IMTV and LA volume was 0.41 (p value = 0.0001), and 0.246 (p value = 0.074) between IMT and LA volume. IMTV significantly correlates with LA volume. Further studies are warranted to verify whether this parameter can be used clinically as a marker of cerebrovascular risk. (orig.)

  8. Masseter muscle thickness in different skeletal morphology: An ultrasonographic study

    Directory of Open Access Journals (Sweden)

    Rani Sushma

    2010-01-01

    Full Text Available Background: The thickness of the masseter muscle during relaxation and contraction states was measured by ultrasonography. Subjects were classified according to their sagittal skeletal relationships. The association between muscle thickness and facial morphology was studied. Context: Masseter muscle thickness influences the skeletal patterns. Aim: To measure and compare the thickness of the masseter muscle in individuals with skeletal class I occlusion and skeletal class II malocclusions and to correlate its relationship with craniofacial morphology. Settings and Design: The study was conducted in a hospital setup and was designed to study the thickness of the masseter muscle in different skeletal morphologies. Materials and Methods: Seventy two individuals between the ages of 18 and 25 years were divided into Group I, Group IIA and Group IIB according to their skeletal relationships. Masseter muscle thickness was measured by ultrasonography. Eight linear and six angular cephalometric measurements were assessed. Statistical Analysis Used: Analysis of variance and Pearson′s correlation analysis. Results: There was a statistically significant difference in muscle thickness between subjects of different skeletal patterns. Significant positive correlation between masseter muscle thickness and posterior total face height, jarabak ratio, ramus height, mandibular length and significant negative correlations with mandibular plane angle, gonial angle and PP-MP angle were observed. Conclusion: This study indicates the strong association between the masseter muscle and skeletal morphology.

  9. April / May 2006. 108 Harvesting split thickness skin in

    African Journals Online (AJOL)

    user

    was to evaluate the outcome split thickness skin graft harvested using sterile razor blade in an areas of scarcity. Methods: A retrograde study of 108 patients who had split thickness skin graft done using a razorblade as harvester from August 1999 to March 2005 at Menilik ii Hospital. Fifty-one (47%) of patients were male ...

  10. Retinal nerve fibre layer thickness values and their associations with ...

    African Journals Online (AJOL)

    analysis showed that thicker mean global RNFL thickness was significantly associated with younger age, shorter axial length (AL) ... Mean RNFL thickness decreased by approximately 0.11 µm per year of aging life, and by 1.02 µm ... assessing factors that influence this parameter and diagnosing diseases affecting it.

  11. Improving harvester estimates of bark thickness for radiata pine ...

    African Journals Online (AJOL)

    Radiata pine bark thickness data from harvested logs and permanent sample plots (PSP) were analysed to determine best-fit coefficients for current and potential future harvester bark thickness models. The most ... Further research will determine if this approach produces acceptable results when optimising bucking.

  12. Ice thickness, volume and subglacial topography of Urumqi Glacier ...

    Indian Academy of Sciences (India)

    accuracy of ice thickness was 4.0% and 4.8% for. 2001 and 2006, respectively, resulting in the accu- racy of glacier volume within 6.0%. The assump- tion that the ..... able development of the ecological environment, industry, and agriculture in Xinjiang Uygur. Autonomous Region. 5. Conclusion and outlook. Ice thickness of ...

  13. Mortality by Level of Emphysema and Airway Wall Thickness

    DEFF Research Database (Denmark)

    Johannessen, Ane; Skorge, Trude Duelien; Bottai, Matteo

    2013-01-01

    There is limited knowledge of the prognostic value of quantitative computed tomography (CT) measures of emphysema and airway wall thickness (AWT) on mortality.......There is limited knowledge of the prognostic value of quantitative computed tomography (CT) measures of emphysema and airway wall thickness (AWT) on mortality....

  14. Thickness and dielectric constant determination of thin dielectric layers

    NARCIS (Netherlands)

    de Bruijn, H.E.; de Bruijn, Helene E.; Minor, Marcel; Kooyman, R.P.H.; Greve, Jan

    1993-01-01

    We derive a method for the determination of the dielectric constant and thickness of a thin dielectric layer, deposited on top of a thick dielectric layer which is in turn present on a metal film. Reflection of p- and s-polarized light from the metal layer yields minima for certain angles of

  15. Origami-Inspired Folding of Thick, Rigid Panels

    Science.gov (United States)

    Trease, Brian P.; Thomson, Mark W.; Sigel, Deborah A.; Walkemeyer, Phillip E.; Zirbel, Shannon; Howell, Larry; Lang, Robert

    2014-01-01

    To achieve power of 250 kW or greater, a large compression ratio of stowed-to-deployed area is needed. Origami folding patterns were used to inspire the folding of a solar array to achieve synchronous deployment; however, origami models are generally created for near-zero-thickness material. Panel thickness is one of the main challenges of origami-inspired design. Three origami-inspired folding techniques (flasher, square twist, and map fold) were created with rigid panels and hinges. Hinge components are added to the model to enable folding of thick, rigid materials. Origami models are created assuming zero (or near zero) thickness. When a material with finite thickness is used, the panels are required to bend around an increasingly thick fold as they move away from the center of the model. The two approaches for dealing with material thickness are to use membrane hinges to connect the panels, or to add panel hinges, or hinges of the same thickness, at an appropriate width to enable folding.

  16. Effects of thickness on electronic structure of titanium thin films

    Indian Academy of Sciences (India)

    Effects of thickness on the electronic structure of e-beam evaporated thin titanium films were studied using near-edge X-ray absorption fine structure (NEXAFS) technique at titanium 2,3 edge in total electron yield (TEY) mode and transmission yield mode. Thickness dependence of 2,3 branching ratio (BR) of titanium was ...

  17. Thick melanoma: prognostic value of positive sentinel nodes

    NARCIS (Netherlands)

    Vermeeren, Lenka; van der Ent, Fred W. C.; Sastrowijoto, Prapto S. H.; Hulsewé, Karel W. E.

    2009-01-01

    BACKGROUND: Sentinel lymph node biopsy (SNB) is a widely accepted procedure used to accurately stage patients with melanoma. Its value in patients with thick melanoma (Breslow thickness >4 mm) is reason for discussion because of the generally poor prognosis of these patients. The purpose of this

  18. Pelvic floor muscle thickness measured by perineal ultrasonography

    DEFF Research Database (Denmark)

    Bernstein, Inge Thomsen; Juul, N; Grønvall, S

    1991-01-01

    Pelvic floor muscle thickness was assessed in nine healthy female physiotherapists by perineal sonography. All measurements were performed as triple-measurements. The aims were to assess the reliability of the measurements and to establish a reference material. The muscle thickness at rest...

  19. Elastomer modulus and dielectric strength scaling with sample thickness

    Science.gov (United States)

    Larson, Kent

    2015-04-01

    Material characteristics such as adhesion and dielectric strength have well recognized dependencies on material thickness. There is disagreement, however, on the scale: the long held dictum that dielectric strength is inversely proportional to the square root of sample thickness has been shown to not always hold true for all materials, nor for all possible thickness regions. In D-EAP applications some studies have postulated a "critical thickness" below which properties show significantly less thickness dependency. While a great deal of data is available for dielectric strength, other properties are not nearly as well documented as samples get thinner. In particular, elastic modulus has been found to increase and elongation to decrease as sample thickness is lowered. This trend can be observed experimentally, but has been rarely reported and certainly does not appear in typical suppliers' product data sheets. Both published and newly generated data were used to study properties such as elastic modulus and dielectric strength vs sample thickness in silicone elastomers. Several theories are examined to explain such behavior, such as the impact of defect size and of common (but not well reported) concentration gradients that occur during elastomer curing that create micron-sized layers at the upper and lower interfaces with divergent properties to the bulk material. As Dielectric Electro-Active Polymer applications strive to lower and lower material thickness, changing mechanical properties must be recognized and taken into consideration for accurate electro-mechanical predictions of performance.

  20. Optimum insulation thickness in wood-framed homes.

    Science.gov (United States)

    A.E. Oviatt

    1975-01-01

    New design methods must be developed to reduce energy waste in buildings. This study examines an economic approach to the design of thermal insulation in the home and demonstrates graphically that an optimum point of insulation thickness occurs where total costs of insulation and energy over the useful life of a building are a minimum. The optimum thickness thus...

  1. The Effect of Endometrial Thickness on In vitro Fertilization (IVF ...

    African Journals Online (AJOL)

    The value of measuring the endometrial thickness and studying the endometrial receptivity in the context of assisted conception remains a contentious issue. A prospective analysis was carried out to determine the effect of endometrial thickness on IVF - embryo transfer / ICSI outcome in dedicated Assisted Reproductive ...

  2. Thickness effect in composite laminates in static and fatigue loading

    NARCIS (Netherlands)

    Lahuerta Calahorra, F.

    2017-01-01

    Thick Laminates (above 6mm) are increasingly present in large composites structures such as wind turbine blades. Designs are based on static and fatigue coupon tests performed on 1-4mm thin laminates. However, a thickness effect has been observed in limited available experimental data. For this

  3. Screen printed nanosized ZnO thick film

    Indian Academy of Sciences (India)

    Unknown

    It was then dried under IR radiation. The thickness of the film was measured to be 30 µm using a film thickness monitoring gauge (Hanatek 8010). 2.2 Optical studies. The ZnO colloids were characterized by optical absorp- tion measurements using spectrophotometer JascoV-570. (UV/Vis/IR). Fluorescence studies at ...

  4. Sputtering of Thick Deuterium Films by KeV Electrons

    DEFF Research Database (Denmark)

    Thestrup Nielsen, Birgitte; Svendsen, Winnie Edith; Schou, Jørgen

    1994-01-01

    Sputtering of thick films of solid deuterium up to several μm by keV electrons is reported for the first time. The sputtering yield increases within a narrow range of thicknesses around 1.6 μm by about 2 orders of magnitude for 1.5 keV electrons. A similar behavior has not been observed for ion...

  5. Impact of oxide thickness on gate capacitance – Modelling and ...

    Indian Academy of Sciences (India)

    gate capacitance and threshold voltage with nanoscale variation of oxide thickness in AlInN/GaN and AlGaN/GaN metal ... The dependence of threshold voltage model on oxide thickness for MOSHEMT is presented in §4. ... The concept of QC was first introduced by Luryi [9] and it originates from the penetra- tion of Fermi ...

  6. Choroidal thickness evaluation in paediatric patients with adenotonsillar hypertrophy.

    Science.gov (United States)

    Yenigun, A; Elbay, A; Hafiz, A M; Ozturan, O

    2017-09-01

    To investigate choroidal thickness using enhanced-depth imaging optical coherence tomography in paediatric patients with adenotonsillar hypertrophy, with comparison to healthy children, three months after adenotonsillectomy. The patients were assigned to three groups: an adenotonsillar hypertrophy group, an adenotonsillectomy group and a healthy control group. In all groups, subfoveal, temporal and nasal choroidal thickness measurements were taken. In the subfoveal, temporal and nasal regions, choroidal tissue was found to be significantly thinner in adenotonsillar hypertrophy children than healthy children (p = 0.012, p = 0.027 and p = 0.020). The subfoveal and temporal choroidal thickness measurements of adenotonsillar hypertrophy group cases were significantly decreased compared to those in the adenotonsillectomy group (p = 0.038 and p = 0.048). There was a significant association between decreased choroidal thickness and adenotonsillar hypertrophy. Adenotonsillar hypertrophy may play an important role in decreased choroidal thickness.

  7. The Thickness of Amalgamations and Cartesian Product of Graphs

    Directory of Open Access Journals (Sweden)

    Yang Yan

    2017-08-01

    Full Text Available The thickness of a graph is the minimum number of planar spanning subgraphs into which the graph can be decomposed. It is a measurement of the closeness to the planarity of a graph, and it also has important applications to VLSI design, but it has been known for only few graphs. We obtain the thickness of vertex-amalgamation and bar-amalgamation of graphs, the lower and upper bounds for the thickness of edge-amalgamation and 2-vertex-amalgamation of graphs, respectively. We also study the thickness of Cartesian product of graphs, and by using operations on graphs, we derive the thickness of the Cartesian product Kn □ Pm for most values of m and n.

  8. Barium titanate thick films prepared by screen printing technique

    Directory of Open Access Journals (Sweden)

    Mirjana M. Vijatović

    2010-06-01

    Full Text Available The barium titanate (BaTiO3 thick films were prepared by screen printing technique using powders obtained by soft chemical route, modified Pechini process. Three different barium titanate powders were prepared: i pure, ii doped with lanthanum and iii doped with antimony. Pastes for screen printing were prepared using previously obtained powders. The thick films were deposited onto Al2O3 substrates and fired at 850°C together with electrode material (silver/palladium in the moving belt furnace in the air atmosphere. Measurements of thickness and roughness of barium titanate thick films were performed. The electrical properties of thick films such as dielectric constant, dielectric losses, Curie temperature, hysteresis loop were reported. The influence of different factors on electrical properties values was analyzed.

  9. Thick lens chromatic effective focal length variation versus bending

    Science.gov (United States)

    Sparrold, Scott

    2017-11-01

    Longitudinal chromatic aberration (LCA) can limit the optical performance in refractive optical systems. Understanding a singlet's chromatic change of effective focal leads to insights and methods to control LCA. Long established, first order theory, shows the chromatic change in focal length for a zero thickness lens is proportional to it's focal length divided by the lens V number or inverse dispersion. This work presents the derivation of an equation for a thick singlet's chromatic change in effective focal length as a function of center thickness, t, dispersion, V, index of refraction, n, and the Coddington shape factor, K. A plot of bending versus chromatic focal length variation is presented. Lens thickness does not influence chromatic variation of effective focal length for a convex plano or plano convex lens. A lens's center thickness'influence on chromatic focal length variation is more pronounced for lower indices of refraction.

  10. The impact of maternal adiposity specialization on infant birthweight: upper versus lower body fat.

    Science.gov (United States)

    Sundermann, Alexandra C; Abell, Troy D; Baker, Lisa C; Mengel, Mark B; Reilly, Kathryn E; Bonow, Michael A; Hoy, Gregory E; Clover, Richard D

    2016-11-01

    The specialization of human fat deposits is an inquiry of special importance in the study of fetal growth. It has been theorized that maternal lower-body fat is designated specifically for lactation and not for the growth of the fetus. Our goal was to compare the contributions of maternal upper-body versus lower-body adiposity to infant birth weight. We hypothesized that upper-body adiposity would be strongly associated with infant birth weight and that lower-body adiposity would be weakly or negligibly associated with infant birth weight-after adjusting for known determinants. In this prospective cohort study, 355 women initiated medical pre-natal care during the first trimester of pregnancy at The University of Oklahoma Health Sciences Center during 1990-1993. Maternal anthropometric measurements were assessed at the first clinic visit: (a) height; (b) weight; (c) circumferences of the upper arm, forearm, and thigh; and, (d) skin-fold measurements of the bicep, subscapular region, and thigh. Infant birth weight was regressed on known major determinants to create the foundational model. Maternal anthropometric variables subsequently were added one at a time into this multiple regression model. The highest contribution by a single anthropometric variable to infant birthweight was, in order: subscapular skin-fold, forearm circumference, and thigh circumference. With one upper-body (subscapular skin-fold) and one lower-body (circumference of the thigh) adiposity measure in the model, the z-score regression coefficient (s.e.) was 85.7g (30.8) [p=0.0057] for maternal subscapular skin-fold and 19.0g (31.6) [p=0.5477] for circumference of the thigh. When the second-best upper-body contributor to infant birthweight (circumference of the forearm) was entered with one lower-body measure into the model, the z-score regression coefficient (s.e.) was 77.5g (38.5) [p=0.0451] for maternal forearm circumference and 14.1g (38.5) [p=0.7146] for circumference of the thigh. When both

  11. Validation of Cooper's ligament thickness in software breast phantoms

    Science.gov (United States)

    Kuperavage, Adam J.; Imran, Abdullah-Al-Zubaer; Bakic, Predrag R.; Maidment, Andrew; Pokrajac, David D.

    2017-03-01

    Anthropomorphic breast phantoms are important tools for a wide range of tasks including pre-clinical validation of novel imaging techniques. In order to improve the realism in the phantoms, assessment of simulated anatomical structures is crucial. Thickness of simulated Cooper's ligaments influences the percentage of dense tissue, as well as qualitative and quantitative properties of simulated images. We introduce three methods (2-dimensional watershed, 3-dimensional watershed, and facet counting) to assess the thickness of the simulated Cooper's ligaments in the breast phantoms. For the validation of simulated phantoms, the thickness of ligaments has been measured and compared with the input thickness values. These included a total of 64 phantoms with nominal ligament thicknesses of 200, 400, 600, and 800 μm. The 2-dimensional and 3-dimensional watershed transformations were performed to obtain the median skeleton of the ligaments. In the 2-dimensional watershed, the median skeleton was found cross-section by cross-section, while the skeleton was found for the entire 3-dimensional space in the 3-dimensional watershed. The thickness was calculated by taking the ratio of the total volume of ligaments and the volume of median skeleton. In the facet counting method, the ligament thickness was estimated as a ratio between estimated ligaments' volume and average ligaments' surface area. We demonstrated that the 2-dimensional watershed technique overestimates the ligament thickness. Good agreement was found between the facet counting technique and the 3-dimensional watershed for assessing thickness. The proposed techniques are applicable for ligaments' thickness estimation on clinical breast images, provided segmentation of Cooper's ligaments has been performed.

  12. Effect of Corneal Thickness on the Penetration of Topical Vancomycin.

    Science.gov (United States)

    Spierer, Oriel; Regenbogen, Michael; Lazar, Moshe; Yatziv, Yossi

    2015-10-01

    To study the influence of corneal thickness on intraocular penetration of topical ophthalmic drops, using vancomycin 50 mg/mL drops as a model. The study included 58 eyes of 58 patients undergoing phacoemulsification cataract extraction. The central corneal thickness was measured by ultrasonic pachymetry on the day of surgery. Thirty minutes before the surgery, one drop of topical vancomycin 50 mg/mL was instilled three times with 10-minute intervals: 30 minutes, 20 minutes, and 10 minutes before the surgery. At the beginning of surgery, a small specimen of aqueous humor was aspirated and sent to the laboratory for measurement of drug concentration to determine the effect of corneal thickness on vancomycin concentration in the anterior chamber. There was insufficient amount of aqueous humor for analysis in 9 samples, leaving a total of 49 samples. The mean central corneal thickness was 539.7 (±39.5) μm (range, 458 to 635 μm). The mean vancomycin concentration in the anterior chamber was 0.220 (±0.209) μg/mL. There was no significant association between vancomycin concentration and corneal thickness (r = -0.07, p = 0.62, Pearson correlation). When patients were divided into three groups based on the mean (±1 SD) central corneal thickness, no significant differences in vancomycin concentrations (in micrograms per milliliter) were encountered: 0.267 (±0.247) (for corneal thickness thickness of 500.2 to 579.2 μm), and 0.200 (±0.160) (for corneal thickness >579.2 μm) (p = 0.73, analysis of variance). Corneal thickness does not influence the penetration of topically applied vancomycin into the anterior chamber.

  13. Knee cartilage segmentation and thickness computation from ultrasound images.

    Science.gov (United States)

    Faisal, Amir; Ng, Siew-Cheok; Goh, Siew-Li; Lai, Khin Wee

    2017-08-29

    Quantitative thickness computation of knee cartilage in ultrasound images requires segmentation of a monotonous hypoechoic band between the soft tissue-cartilage interface and the cartilage-bone interface. Speckle noise and intensity bias captured in the ultrasound images often complicates the segmentation task. This paper presents knee cartilage segmentation using locally statistical level set method (LSLSM) and thickness computation using normal distance. Comparison on several level set methods in the attempt of segmenting the knee cartilage shows that LSLSM yields a more satisfactory result. When LSLSM was applied to 80 datasets, the qualitative segmentation assessment indicates a substantial agreement with Cohen's κ coefficient of 0.73. The quantitative validation metrics of Dice similarity coefficient and Hausdorff distance have average values of 0.91 ± 0.01 and 6.21 ± 0.59 pixels, respectively. These satisfactory segmentation results are making the true thickness between two interfaces of the cartilage possible to be computed based on the segmented images. The measured cartilage thickness ranged from 1.35 to 2.42 mm with an average value of 1.97 ± 0.11 mm, reflecting the robustness of the segmentation algorithm to various cartilage thickness. These results indicate a potential application of the methods described for assessment of cartilage degeneration where changes in the cartilage thickness can be quantified over time by comparing the true thickness at a certain time interval.

  14. Retinal peripapillary nerve fiber layer thickness in neuromyelitis optica.

    Science.gov (United States)

    Merle, Harold; Olindo, Stéphane; Donnio, Angélique; Richer, Raymond; Smadja, Didier; Cabre, Philippe

    2008-10-01

    To measure the thickness of retinal peripapillary nerve fibers throughout the course of neuromyelitis optica (NMO). This study was of a cross-sectional design, examining the thickness of the retinal peripapillary nerve fiber layer by optical coherence tomography, in patients with NMO (n = 15; 30 eyes), patients with multiple sclerosis (MS; n = 15; 30 eyes), and a control group (n = 23; 46 eyes). The thicknesses were acquired according to protocol with the fast RNFL (Retinal Nerve Fiber Layer) procedure. The study of visual function includes for each eye a determination of refraction, measurement of visual acuity, measurement of contrast vision, an analysis of color vision, and a frequency-doubling technology perimetry (FDTP). The main outcome measurements were the thickness of the retinal peripapillary nerve fibers, visual acuity, and scores of contrast vision. The average thickness of retinal peripapillary nerve fibers was respectively in the NMO, MS, and control group: 65.44 +/- 24.19, 83.85 +/- 24.12, and 106.24 +/- 12.46 microm (P = 0.01). The average thickness of retinal peripapillary nerve fibers correlated to visual acuity, the scores of contrast vision, the scores of FDTP, and the number of episodes per patient (r = -0.58, P = 0.03). This is the first study to produce measurements of the thickness of retinal peripapillary nerve fibers during optic neuropathies of NMO. The optic neuropathies of NMO are also accompanied by an acute and chronic axonal loss, as clearly illustrated by the OCT.

  15. Facial soft tissue thickness in North Indian adult population

    Directory of Open Access Journals (Sweden)

    Tanushri Saxena

    2012-01-01

    Full Text Available Objectives: Forensic facial reconstruction is an attempt to reproduce a likeness of facial features of an individual, based on characteristics of the skull, for the purpose of individual identification - The aim of this study was to determine the soft tissue thickness values of individuals of Bareilly population, Uttar Pradesh, India and to evaluate whether these values can help in forensic identification. Study design: A total of 40 individuals (19 males, 21 females were evaluated using spiral computed tomographic (CT scan with 2 mm slice thickness in axial sections and soft tissue thicknesses were measured at seven midfacial anthropological facial landmarks. Results: It was found that facial soft tissue thickness values decreased with age. Soft tissue thickness values were less in females than in males, except at ramus region. Comparing the left and right values in individuals it was found to be not significant. Conclusion: Soft tissue thickness values are an important factor in facial reconstruction and also help in forensic identification of an individual. CT scan gives a good representation of these values and hence is considered an important tool in facial reconstruction- This study has been conducted in North Indian population and further studies with larger sample size can surely add to the data regarding soft tissue thicknesses.

  16. Mammographic thickness compensation for image analysis and display enhancement

    Science.gov (United States)

    Rico, Dan; Yaffe, Martin J.; Augustine, Bindu J.; Mawdsley, Gordon E.

    2003-05-01

    This paper proposes a novel algorithm for mammographic image enhancenment, based on identifying the peripheral region of the breast and suppressing the large change in signal caused by reduction of thickness there, while maintaining the local contrast information related to tissue composition. The thickness compensation algorithm consists of three processing steps. The first step is to generate a thickness map using two phantoms, one which simulates the shape of the breast in the cranio-caudal projection and a second one as a triangular attenuator. The second step is to warp the phantom thickness map in the peripheral region to that of the breast image. The third step is to equalize the signal values in the peripheral region relative to the signal in the uniform thickness area using the warped thickness map data. Examples are presented to show the effectiveness of the proposed method in effectively suppressing the large range of signal caused by thickness changes in the peripheral region, thereby facilitating image presentation and analysis. The performance of the proposed algorithm was also evaluated on clinical mammograms by computing volumetric breast density.

  17. Bone thickness of the anterior palate for orthodontic miniscrews.

    Science.gov (United States)

    Holm, Maike; Jost-Brinkmann, Paul-Georg; Mah, James; Bumann, Axel

    2016-09-01

    To determine the bone thickness in the anterior palate and to test whether there is any dependency between bone thickness and patient's age or gender and whether there is any difference between left and right sides. Cone beam computed tomographic (CBCT) evaluations (n  =  431; 229 females, 202 males) of healthy orthodontic patients aged 9-30 years were selected from the database of the imaging center network Mesantis. In each CBCT image, palatal bone thickness was determined as the median and 2, 4, 6, and 8 mm paramedian bilaterally. Bone height was measured perpendicularly to the bony surface at 10, 12, 14, 16, 18, and 20 mm from the cementoenamel junction of the maxillary central incisor in the sagittal plane. The greatest bone thickness was found in the lateral anterior palate. Palatal bone thickness of male patients was on average 1.2 mm greater than that of females. Bone height of 9-13-year-olds was less than that of older patients. No difference could be determined between the left and right side. The lateral anterior palate offers the greatest bone thickness. Because there is considerable variation of bone thickness between individuals, a CBCT evaluation is recommended if maximum screw length is to be used.

  18. Comparison of equine articular cartilage thickness in various joints.

    Science.gov (United States)

    Lee, Hyeon; Kirkland, W Grant; Whitmore, Ryan N; Theis, Kelcie M; Young, Hannah E; Richardson, Ashton J; Jackson, Robert L; Hanson, R Reid

    2014-01-01

    Thicknesses of fresh equine articular cartilage surfaces from the fetlock, carpal and stifle joints were measured employing a needle probe test. Eighty-seven samples used in measurement were cultivated from fetlock, carpal and stifle joints of 12 deceased within 4 h of death. After approximately three minutes of exposure to air during dissection, all cartilage samples were preserved in a saline solution to keep the articular cartilage hydrated for testing. The thickness was measured on five different spots on the same sample. The thicknesses of the fetlock, carpus and stifle were compared. The articular cartilage of the stifle was thicker than the fetlock and carpus, while the fetlock and the carpus had similar thickness values. The average thickness of the fetlock, carpal and stifle joint are 0.86, 0.87 and 2.1 mm, respectively. They were statistically compared using the Student t-test. The differences on the articular cartilage thicknesses between the fetlock and stifle, and carpus and stifle were "very highly significant" (p fetlock and carpus. Four different surfaces in the fetlock and four in the carpal joint were also compared. Significant differences between each set of the four surfaces were not observed. In the carpus, the difference in thickness between the distal radius and proximal third carpal bone articular cartilage surfaces as well as the proximal radial carpal bone and distal radial carpal bone articular cartilage surfaces were statistically significant.

  19. Gauging the Galactic thick disk with RR Lyrae stars

    Directory of Open Access Journals (Sweden)

    Cruz G.

    2012-02-01

    Full Text Available In this contribution we present results from the QUEST RR Lyrae Survey of the thick disk. The survey spans ~480 sq. deg. at low latitude |b| < 30°, with multi-epoch VRI observations, obtained with the QUEST-I camera at the 1m Jürgen Stock Schmidt telescope located at the National Astronomical Observatory of Venezuela. This constitutes the first deep RR Lyrae survey of the Galactic thick disk conducted at low galactic latitudes, covering simultaneously a large range in radial (8thick disk structural parameters from in situ RR Lyrae stars having accurate distances (errors <7% and individual reddenings derived from each star’s color curve at minimum light. Moreover, the use of RR Lyrae stars as tracers ensures negligible contamination from the Galactic thin disk. We find a thick disk mean scale height hZ = 0.94 ± 0.11kpc and scale length hR = 3.2 ± 0.4kpc, derived from the vertical and radial mean density profiles of RR Lyrae stars. We also find evidence of thick disk flaring and results that may suggest the thick disk radial density profile shows signs of antitruncation. We discuss our findings in the context of recent thick disk formation models.

  20. Skinfold Parameter as Predictor of Body Density for Undergraduate ...

    African Journals Online (AJOL)

    DATONYE ALASIA

    Complex Diseases in PCOS Probands of. South Indian Population. Asian Journal of. E p i d e m i o l o g y 2 0 1 2 ; 5 : 5 0 -. 55.10.3923/aje.2012.50.55. 7. Gill BK. Sandhu PK. Factor Analysis of. Anthropometric, Physiometric and. Metabolic Risk Traits Associated with. Cardiovascular Diseases in North Indian. Punjabi Adults.

  1. Synthesis of nanometre-thick MoO3 sheets

    Science.gov (United States)

    Kalantar-Zadeh, Kourosh; Tang, Jianshi; Wang, Minsheng; Wang, Kang L.; Shailos, Alexandros; Galatsis, Kosmas; Kojima, Robert; Strong, Veronica; Lech, Andrew; Wlodarski, Wojtek; Kaner, Richard B.

    2010-03-01

    The formation of MoO3 sheets of nanoscale thickness is described. They are made from several fundamental sheets of orthorhombic α-MoO3, which can be processed in large quantities via a low cost synthesis route that combines thermal evaporation and mechanical exfoliation. These fundamental sheets consist of double-layers of linked distorted MoO6 octahedra. Atomic force microscopy (AFM) measurements show that the minimum resolvable thickness of these sheets is 1.4 nm which is equivalent to the thickness of two double-layers within one unit cell of the α-MoO3 crystal.

  2. Triaxial MEMS accelerometer with screen printed PZT thick film

    DEFF Research Database (Denmark)

    Hindrichsen, Christian Carstensen; Almind, Ninia Sejersen; Brodersen, Simon Hedegaard

    2010-01-01

    Piezoelectric thick films have increasing interest due to the potential high sensitivity and actuation force for MEMS sensors and actuators. The screen printing technique is a promising deposition technique for realizing piezoelectric thick films in the thickness range from 10-100 mu m. In this w...... and the first mode resonance frequency is 11 kHz. A Finite Element Method (FEM) model is used to validate the measured sensitivity and resonance frequency. Good agreement between the model and the measurements is seen....

  3. Evolução de parâmetros antropométricos em portadores do vírus da Imunodeficiência Humana ou com Síndrome da Imunodeficiência Adquirida: um estudo prospectivo Changes in the anthropometric parameters of patients with the Human Immunodeficiency virus or Acquired Immunodeficiency Syndrome: a prospective study

    Directory of Open Access Journals (Sweden)

    Maíra Ladeia Rodrigues Curti

    2010-02-01

    Full Text Available OBJETIVO: Avaliar o estado nutricional e a evolução de parâmetros antropométricos para alterações morfológicas em pacientes vivendo com o vírus da Imunodeficiência Humana ou com Síndrome da Imunodeficiência Adquirida em uso de terapia antirretroviral de alta atividade. MÉTODOS: Trata-se de estudo de coorte prospectiva com duração de 12 meses, envolvendo indivíduos adultos, de ambos os sexos, em terapia antirretroviral recém introduzida. Os indicadores antropométricos estudados foram índice de massa corporal, circunferência de cintura, dobras cutâneas subescapular, biciptal e triciptal, avaliados com intervalos de três meses, totalizando 4 medidas do tempo. Variáveis foram descritas segundo mediana e percentis 25 e 75 e analisadas por ANOVA para medidas repetidas. RESULTADOS: A população estudada foi composta por 53 indivíduos, a maioria do sexo masculino (81%, entre 30 e 39 anos. Apenas a dobra cutânea subescapular apresentou significante variação no tempo (T1=13,7 vs T4=16,0; pOBJECTIVE: The objective of this study was to assess the nutritional status and changes in the anthropometric indicators of patients with the human Immunodeficiency virus or acquired immunodeficiency syndrome using the highly active antiretroviral therapy. METHODS: This is a 12-month prospective cohort study of adult males and females who recently started antiretroviral therapy. The anthropometric indicators studied were body mass index, waist circumference and subscapular, biceps and triceps skinfold thicknesses, taken 4 times during the year in 3-month intervals. The variables were described according to medians and 25 and 75 percentiles and analyzed by ANOVA for repeated measurements. RESULTS: The studied population consisted of 53 patients, mostly males (81% aged 30 to 39 years. Only subscapular skinfold thickness changed significantly over time (T1=13.70 vs T4=16.00, p<0.001, indicating cervical lipohypertrophy (buffalo hump. CONCLUSION

  4. Dietary Patterns Exhibit Sex-Specific Associations with Adiposity and Metabolic Risk in a Cross-Sectional Study in Urban Mexican Adolescents.

    Science.gov (United States)

    Perng, Wei; Fernandez, Carmen; Peterson, Karen E; Zhang, ZhenZhen; Cantoral, Alejandra; Sanchez, Brisa N; Solano-González, Maritsa; Téllez-Rojo, Martha Maria; Baylin, Ana

    2017-10-01

    Background: Studies in Western nations have shown associations of certain dietary patterns with obesity and metabolic risk in youth. Little is known about these relations in newly industrialized countries where obesity prevalence is surpassing those of developed countries. Objective: We sought to characterize dietary patterns in a cross-sectional study in 224 adolescents aged 8-14 y in Mexico and to investigate associations of the dietary patterns with adiposity and metabolic risk. Methods: We used principal components analysis to derive dietary patterns from food-frequency questionnaire data. By using linear regression models that accounted for mother's marital status, education, and smoking habits and child's age and physical activity, we examined associations of the dietary patterns with adiposity [body mass index z score, waist circumference, the sum and ratio of the subscapular and triceps skinfold thicknesses, blood pressure, serum fasting glucose and a C-peptide-based measure of insulin resistance (CP-IR), lipid profile, and a metabolic syndrome risk z score (MetS z score)]. Results: We identified a "prudent" dietary pattern characterized by high intakes of vegetables, fruit, fish, chicken, and legumes and a "transitioning" dietary pattern, which comprises processed meats, Mexican foods, and sweetened beverages. Each unit increase in the prudent pattern factor score corresponded with 0.33 ng/mL (95% CI: 0.09, 0.57 ng/mL) lower C-peptide, 0.08 units (95% CI: 0.02, 0.13 units) lower CP-IR, and a 0.14 unit (0.00, 0.27 unit) lower MetS z score in boys. In girls, the transitioning pattern corresponded with higher subscapular + triceps skinfold thickness (per 1-unit increase in the factor score: 2.46 mm; 95% CI: 0.10, 4.81 mm). These results did not change after accounting for pubertal status. Conclusions: A prudent dietary pattern was protective against metabolic risk in adolescent boys, whereas a transitioning dietary pattern corresponded with higher adiposity

  5. Carotid intima‑media thickness and insulin resistance changes in ...

    African Journals Online (AJOL)

    -Media Thickness (CIMT), in morbid obese patients without any known associated chronic diseases who underwent sleeve gastrectomy. Materials and Methods: The subjects of this study were patients with minimum BMI of 40, who did not have ...

  6. Carotid intima‑media thickness and insulin resistance changes in ...

    African Journals Online (AJOL)

    2015-09-11

    -Media Thickness (CIMT), in morbid obese patients without any known associated chronic diseases who underwent sleeve gastrectomy. Materials and Methods: The subjects of this study were patients with minimum BMI of 40, ...

  7. Castings Dimensions Influence on the Alloyed Layer Thickness

    Directory of Open Access Journals (Sweden)

    Szajnar J.

    2014-03-01

    Full Text Available The paper presents the results of simulation of alloy layer formation process on the model casting. The first aim of this study was to determine the influence of the location of the heat center on alloy layer’s thickness with the use of computer simulation. The second aim of this study was to predict the thickness of the layer. For changes of technological parameters, the distribution of temperature in the model casting and temperature changes in the characteristic points of the casting were found for established changes of technological parameters. Numerical calculations were performed using programs NovaFlow&Solid. The process of obtaining the alloy layer with good quality and proper thickness depends on: pouring temperature, time of premould hold at the temperature above 1300°C. The obtained results of simulation were loaded to authorial program Preforma 1.1 in order to determine the predicted thickness of the alloy casting.

  8. Critical thickness for the agglomeration of thin metal films

    Energy Technology Data Exchange (ETDEWEB)

    Boragno, C.; Buatier de Mongeot, F.; Felici, R.; Robinson, I.K.; (U Genova); (ESRF); (UCL)

    2009-09-15

    A thin metal film can exist in a metastable state with respect to breaking into small clusters. In this paper we report on grazing incidence small-angle x-ray scattering studies carried out in situ during the annealing of thin Ni films, between 2 and 10 nm thick, deposited on an amorphous SiO{sub 2} substrate. Our results show the presence of two different regimes which depend on the initial film thickness. For thicknesses less than 5 nm the annealing results in the formation of small, compact clusters on top of a residual Ni wetting layer. For thicknesses greater than 5 nm the film breaks into large, well-separated clusters and the substrate shows an uncovered clean surface.

  9. Russian River Ice Thickness and Duration, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of river ice thickness measurements, and beginning and ending dates for river freeze-up events from fifty stations in northern Russia. The...

  10. Using laser to measure stem thickness and cut weed stems

    DEFF Research Database (Denmark)

    Heisel, T.; Schou, Jørgen; Andreasen, C.

    2002-01-01

    Stem thickness of the weed Solanum nigrum and the crop sugarbeet was determined with a He-Ne laser using a novel non-destructive technique measuring stem shadow. Thereafter, the stems were cut close to the soil surface with a CO2 laser. Treatments were carried out on pot plants, grown...... in the greenhouse, at two different growth stages, and plant dry matter was measured 2-5 weeks after treatment. The relationship between plant dry weight and laser energy was analysed using two different non-linear dose-response regression models; one model included stem thickness as a variable, the other did not....... A binary model was also tested. The non-linear model incorporating stem thickness described the data best, indicating that it would be possible to optimize laser cutting by measuring stem thickness before cutting. The general tendency was that more energy was needed the thicker the stem. Energy uses...

  11. Improved thick film semiconductor/solar cell contacts

    Science.gov (United States)

    Ross, B.

    1979-01-01

    The postulated concept of low-temperature all-metal thick film electrodes is discussed. It is noted that the mechanical and metallurgical properties of the electrodes are excellent, but electrical parameters remain to be optimized.

  12. Generalized thickness of the Minnelusa Formation, Black Hills, South Dakota.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set is a polygon coverage created in ARC/INFO that represents the generalized thickness of the Minnelusa Formation, Black Hills, South Dakota. The...

  13. Estimated Thickness of the Lower Miocene 1 Sequence, Gulf Coast

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The thickness contours were created using biostratigraphic data in the Paleo-Data, Inc., Tenroc Regional Geologic Database. The depths of the microfossil locations...

  14. Multiplexed Holographic Optical Data Storage In Thick Bacteriorhodopsin Films

    Science.gov (United States)

    Downie, John D.; Timucin, Dogan A.; Gary, Charles K.; Ozcan, Meric; Smithey, Daniel T.; Crew, Marshall

    1998-01-01

    The optical data storage capacity of photochromic bacteriorhodopsin films is investigated by means of theoretical calculations, numerical simulations, and experimental measurements on sequential recording of angularly multiplexed diffraction gratings inside a thick D85N BR film.

  15. Gridded Observational Sea Ice Thickness Products, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — Fields of long-term mean spring ice thickness derived from ERS-1 (1993-2001) and CryoSat (2011 to 2013) radar altimeters, ICESat laser altimeter (2004 to 2009),...

  16. Benefits of the Multiple Echo Technique for Ultrasonic Thickness Testing

    Energy Technology Data Exchange (ETDEWEB)

    Elder, J.; Vandekamp, R.

    2011-02-10

    Much effort has been put into determining methods to make accurate thickness measurements, especially at elevated temperatures. An accuracy of +/- 0.001 inches is typically noted for commercial ultrasonic thickness gauges and ultrasonic thickness techniques. Codes and standards put limitations on many inspection factors including equipment, calibration tolerance and temperature variations. These factors are important and should be controlled, but unfortunately do not guarantee accurate and repeatable measurements in the field. Most technicians long for a single technique that is best for every situation, unfortunately, there are no 'silver bullets' when it comes to nondestructive testing. This paper will describe and discuss some of the major contributors to measurement error as well as some advantages and limitations of multiple echo techniques and why multiple echo techniques should be more widely utilized for ultrasonic thickness measurements.

  17. Simulation of depth of penetration during ballistic impact on thick ...

    Indian Academy of Sciences (India)

    dimensional models; ballistic impact; thick target; depth of penetration. 1. Introduction. Ballistic impact is the study which deals with projectile hitting the target and observing its effects in terms of deformation and fragmentation of the target. The need ...

  18. A Finite Element Analysis of Optimal Variable Thickness Sheets

    DEFF Research Database (Denmark)

    Petersson, Joakim S

    1996-01-01

    A quasimixed Finite Element (FE) method for maximum stiffness of variablethickness sheets is analysed. The displacement is approximated with ninenode Lagrange quadrilateral elements and the thickness is approximated aselementwise constant. One is guaranteed that the FE displacement solutionswill...

  19. Thickness effect on the fracture and delamination of titanium films

    Energy Technology Data Exchange (ETDEWEB)

    Cordill, M.J., E-mail: megan.cordill@oeaw.ac.at [Erich Schmid Institute of Materials Science, Austrian Academy of Science and the Department of Materials Physics, Montanuniversität Leoben, Jahnstrasse 12, 8700 Leoben (Austria); Taylor, A.A. [Physics Department, Durham University, Durham DH1 3LE (United Kingdom); Laboratory for Mechanics and Nanostructures, Empa, Swiss Federal Laboratories for Materials Testing and Research, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland)

    2015-08-31

    Titanium adhesion layers are a common component of many coated products; they play a particularly important role in promoting the adhesion of Cu and Au conduction lines to polymer substrates for flexible electronic circuitry. In this work a full microstructural and mechanical characterization is performed on Ti layers of three different thicknesses—8, 12 and 50 nm—deposited onto polyimide. Observed differences in the mechanical behavior of the coatings were found to relate to the changing chemistry and grain size of the coatings. In particular, the observation, using transmission electron microscopy, that the two thinner coatings were comprised of 50% or less metallic Ti illustrates the potential pitfalls of altering something so simple as the coating thickness. - Highlights: • Crack behavior changes with film thickness despite film adhesion staying constant. • Ti–PI interlayer and TiO{sub x} surface layer thicknesses do not change with film thickness. • Film and interface characterization provides understanding of mechanical properties.

  20. Study of pipe thickness loss using a neutron radiography method

    Science.gov (United States)

    Mohamed, Abdul Aziz; Wahab, Aliff Amiru Bin; Yazid, Hafizal B.; Ahmad, Megat Harun Al Rashid B. Megat; Jamro, Rafhayudi B.; Azman, Azraf B.; Zin, Muhamad Rawi Md; Idris, Faridah Mohamad

    2014-02-01

    The purpose of this preliminary work is to study for thickness changes in objects using neutron radiography. In doing the project, the technique for the radiography was studied. The experiment was done at NUR-2 facility at TRIGA research reactor in Malaysian Nuclear Agency, Malaysia. Test samples of varying materials were used in this project. The samples were radiographed using direct technique. Radiographic images were recorded using Nitrocellulose film. The films obtained were digitized to processed and analyzed. Digital processing is done on the images using software Isee!. The images were processed to produce better image for analysis. The thickness changes in the image were measured to be compared with real thickness of the objects. From the data collected, percentages difference between measured and real thickness are below than 2%. This is considerably very low variation from original values. Therefore, verifying the neutron radiography technique used in this project.

  1. Modeled Thickness of the Overburden Geomodel Unit (obthk_f)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The obthk_f grid represents the modeled thickness of the Overburden geomodel unit at a 500 foot resolution. It is one grid of a geomodel that consists of eleven...

  2. Advantages of PZT thick film for MEMS sensors

    DEFF Research Database (Denmark)

    Hindrichsen, Christian Carstensen; Lou-Moller, R.; Hansen, K.

    2010-01-01

    For all MEMS devices a high coupling between the mechanical and electrical domain is desired. Figures of merit describing the coupling are important for comparing different piezoelectric materials. The existing figures of merit are discussed and a new figure of merit is introduced for a fair...... comparison of piezoelectric thin and thick films based MEMS devices, as cantilevers, beams, bridges and membranes. Simple analytical modeling is used to define the new figure of merit. The relevant figure of merits is compared for the piezoelectric material of interest for MEMS applications: ZnO, AIN, PZT...... thin film and PZT thick film. It is shown that MEMS sensors with the PZT thick film TF2100 from InSensor A/S have potential for significant higher voltage sensitivities compared to PZT thin film base MEMS sensors when the total thickness of the MEMS cantilever, beam, bridge or membrane is high...

  3. Changes on the corneal thickness and curvature after orthokeratology

    Science.gov (United States)

    Mitsui, Iwane; Yamada, Yoshiya

    2004-07-01

    To evaluate the corneal thickness and curvature changes after Orthokeratology contact lens wear, using the ORBSCAN II corneal topography system, corneal thickness and corneal curvature were measured on one hundred and twenty eyes of sixty patients before and after wearing the custom rigid gas permeable contact lenses for Orthokeratology. The contact lenses were specially designed for each eye. The subjects wore the orthokeratology lenses for approximately Four hours with their eyes closed. The corneal thickness of the subjects was increased on fifty-five eyes at not only the peripheral zone but also the center of the cornea. The average increase of central and peripheral corneal thickness was 18 micrometer and 22micrometer, respectively. The mean anterior curvature of corneal surface changed 1.25D. The mean posterior curvature of corneal endothelium side changed 0.75D.

  4. Greenland 5 km DEM, Ice Thickness, and Bedrock Elevation Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — A Digital Elevation Model (DEM), ice thickness grid, and bedrock elevation grid of Greenland acquired as part of the PARCA program are available in ASCII text format...

  5. Super-resolved thickness maps using ultrahigh resolution OCT

    Science.gov (United States)

    Aranha dos Santos, Valentin; Schmetterer, Leopold; Triggs, Graham J.; Leitgeb, Rainer A.; Werkmeister, René M.

    2017-07-01

    OCT imaging in the super-resolution regime was investigated using simulations and experiments. Samples of known thickness in the range 46-163 nm were fabricated and imaged. Measurements of the tear film lipid layer were performed.

  6. Screen-printed piezoceramic thick films for miniaturised devices

    DEFF Research Database (Denmark)

    Lou-Moeller, R.; Hindrichsen, Christian Carstensen; Thamdrup, Lasse Højlund

    2007-01-01

    The development towards smaller devices with more functions integrated calls for new and improved manufacturing processes. The screen-printing process is quite well suited for miniaturised and integrated devices, since thick films can be produced in this manner without the need for further...... machining. On the other hand, the process of screen printing thick films involves potential problems of thermal matching and chemical compatibility at the processing temperatures between the functional film, the substrate and the electrodes. As an example of such a miniaturised device, a MEMS accelerometer...... based on PZT thick film will be presented. The design and process flow of this accelerometer has been optimised by means of finite element modelling (FEMLAB (c)). Consequently it has proved possible to eliminate post-processing steps after the screen printing of the PZT thick film....

  7. Thickness Effect of Micro Speaker Copper Coil Fabrication Process

    Directory of Open Access Journals (Sweden)

    F. L. AYAT

    2011-07-01

    Full Text Available This paper present the advantage of using electroplating for making the thick layer of copper over the sputtering. The purpose of this paper is to fabricate the copper coil for microspeaker. The design and simulation of this copper coil shows that the 15 um thickness is needed. In order to fabricate this coil, copper plating is used. The electro-deposition process is well suited to make films of metals such as copper, gold and nickel. The films can be made in any thickness from ~1 µm to >100 µm. The deposition is best controlled when used with an external electrical potentiostate. However, it requires electrical contact to the substrate when immersed in the liquid bath. In any process, the surface of the substrate must have an electrically conducting coating before the deposition can be done. The result of this experimental research shows the easy and cheap way to fabricate the thick layer of copper for microspeacker fabrication.

  8. Gulf Coast Estimated Thickness of the Upper Miocene Sequence

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The thickness contours were created using biostratigraphic data in the Paleo-Data, Inc., Tenroc Regional Geologic Database. The depths of the microfossil locations...

  9. GLERL Great Lakes Ice Thickness Data Base, 1966-1979

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — During the winters of 1965/66 through 1976/77, NOAA/Great Lakes Environmental Research Laboratory (GLERL) collected weekly ice thickness and stratigraphy data at up...

  10. Charge Distribution Dependency on Gap Thickness of CMS Endcap RPC

    CERN Document Server

    Park, Sung K.; Lee, Kyongsei

    2016-01-01

    We report a systematic study of charge distribution dependency of CMS Resistive Plate Chamber (RPC) on gap thickness. Prototypes of double-gap RPCs with six different gap thickness ranging from from 1.0 to 2.0 mm in 0.2-mm steps have been built with 2-mm-thick phenolic high-pressure-laminated plates. The efficiencies of the six gaps are measured as a function of the effective high voltages. We report that the strength of the electric fields of the gap is decreased as the gap thickness is increased. The distributions of charges in six gaps are measured. The space charge effect is seen in the charge distribution at the higher voltages. The logistic function is used to fit the charge distribution data. Smaller charges can be produced within smaller gas gap. But the digitization threshold should be also lowered to utilize these smaller charges.

  11. Multispectral UV imaging for determination of the tablet coating thickness

    DEFF Research Database (Denmark)

    Novikova, Anna; Carstensen, Jens Michael; Zeitler, J. Axel

    2017-01-01

    The applicability of off-line multispectral ultraviolet (UV) imaging in combination with multivariate data analysis was investigated to determine the coating thickness and its distribution on the tablet surface during lab scale coating. The UV imaging results were compared with the weight gain...... measured for each individual tablet and the corresponding coating thickness and its distribution measured by terahertz pulsed imaging (TPI). Three different tablet formulations were investigated, two of which contained UV active tablet cores. Three coating formulations were applied: Aquacoat® ECD (a mainly...... translucent coating) and Eudragit® NE (a turbid coating containing solid particles). It was shown that UV imaging is a fast and non-destructive method to predict individual tablet weight gain as well as coating thickness. The coating thickness distribution profiles determined by UV imaging correlated...

  12. Bilayer-thickness-mediated interactions between integral membrane proteins

    CERN Document Server

    Kahraman, Osman; Klug, William S; Haselwandter, Christoph A

    2016-01-01

    Hydrophobic thickness mismatch between integral membrane proteins and the surrounding lipid bilayer can produce lipid bilayer thickness deformations. Experiment and theory have shown that protein-induced lipid bilayer thickness deformations can yield energetically favorable bilayer-mediated interactions between integral membrane proteins, and large-scale organization of integral membrane proteins into protein clusters in cell membranes. Within the continuum elasticity theory of membranes, the energy cost of protein-induced bilayer thickness deformations can be captured by considering compression and expansion of the bilayer hydrophobic core, membrane tension, and bilayer bending, resulting in biharmonic equilibrium equations describing the shape of lipid bilayers for a given set of bilayer-protein boundary conditions. Here we develop a combined analytic and numerical methodology for the solution of the equilibrium elastic equations associated with protein-induced lipid bilayer deformations. Our methodology al...

  13. IceBridge PARIS L2 Ice Thickness V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains contains Greenland ice thickness measurements acquired using the Pathfinder Advanced Radar Ice Sounder (PARIS).The data were collected as part...

  14. Thermal behavior variations in coating thickness using pulse phase thermography

    Energy Technology Data Exchange (ETDEWEB)

    Ranjit, Shrestha; Chung, Yoonjae; Kim, Won Tae [Kongju National University, Cheonan (Korea, Republic of)

    2016-08-15

    This paper presents a study on the use of pulsed phase thermography in the measurement of thermal barrier coating thickness with a numerical simulation. A multilayer heat transfer model was used to analyze the surface temperature response acquired from one-sided pulsed thermal imaging. The test sample comprised four layers: the metal substrate, bond coat, thermally grown oxide and the top coat. The finite element software, ANSYS, was used to model and predict the temperature distribution in the test sample under an imposed heat flux on the exterior of the TBC. The phase image was computed with the use of the software MATLAB and Thermofit Pro using a Fourier transform. The relationship between the coating thickness and the corresponding phase angle was then established with the coating thickness being expressed as a function of the phase angle. The method is successfully applied to measure the coating thickness that varied from 0.25 mm to 1.5 mm.

  15. Aquarius Retrieval of Sea Ice Thickness: Initial Results

    Science.gov (United States)

    De Matthaeis, Paolo; Utku, C.; Le Vine, David M.; Moyer, A.

    2014-01-01

    Aquarius brightness temperature data are used to calculate sea ice thickness in the Arctic region. The method is based on the inversion of a radiative transfer model for icecovered sea. Using this technique, the initial sea ice thickness values retrieved from Aquarius data are compared to the SMOSIce Data as well as to estimates from NASA's Operation IceBridge. The results show similar trends between the SMOS- and Aquarius-derived sea ice thickness, however the Aquarius estimates tend to be higher and noisier than the corresponding SMOS values. The accuracy of retrieved Aquarius ice thickness is possibly influenced by uncertainties in the ancillary input parameters and by the coarser resolutions of Aquarius.

  16. Erratum to: Mapping sediment thickness of Islamabad city using ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 125; Issue 4. Erratum to: Mapping sediment thickness of Islamabad city using empirical relationships: Implications for seismic hazard assessment. Volume 125 Issue 4 June 2016 pp 897-898 ...

  17. Estimated Thickness of the Lower Miocene 2 Sequence, Gulf Coast

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The thickness contours were created using biostratigraphic data in the Paleo-Data, Inc., Tenroc Regional Geologic Database. The depths of the microfossil locations...

  18. Total Sediment Thickness of the World's Oceans & Marginal Seas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A digital total-sediment-thickness database for the world's oceans and marginal seas has been compiled by the NOAA National Geophysical Data Center (NGDC). The data...

  19. A Human Factors Evaluation of Exoskeleton Boot Interface Sole Thickness

    Science.gov (United States)

    2006-06-01

    Abduction Adduction Adduction Abduction Flexion Extension Flexion Extension Dorsiflexion Plantarflexion 23 Appendix B. Comfort, Stability, and...sense is affected by shoe sole thickness but only in dorsiflexion . Our investigation sought to identify, through biomechanical evaluation, human

  20. Specimen thickness effect on elastic-plastic constraint parameter A

    National Research Council Canada - National Science Library

    GP Nikishkov; YuG Matvienko

    2015-01-01

    .... Distributions of the J-integral and constraint parameter A along the crack front for varying specimen thickness and crack depth are determined for edge cracked plate, center cracked plate, three...

  1. Characteristics of salivary secretion in normal-weight, overweight and obese children: a preliminary study: salivary composition and excessive fat tissue.

    Science.gov (United States)

    de Campos, Milene Mazuchi; Kobayashi, Fernanda Yukie; Barbosa, Taís de Souza; Costa, Simone da Silva; Lucas, Bárbara de Lima; Castelo, Paula Midori

    2014-07-01

    Information on salivary characteristics of young subjects with different body composition is scarce. Thus, the aim of this pilot study was to assess salivary characteristics of normal-weight, overweight and obese children. This is a basic research design in which 68 children (5-12 years) were recruited and anthropometric measurements consisted of body mass index (BMI = Kg/m(2)), body perimeters (waist/arm circumferences) and subcutaneous fat tissue (triceps/subscapular thicknesses). Stimulated (SS) and unstimulated morning saliva (US) were collected to determine flow rate, pH and triglycerides, urea, alpha-amylase, total protein, phosphate and calcium concentrations. Data were analyzed using normality tests, t test/Wilcoxon, one-way ANOVA/Kruskal-Wallis and Pearson's/Spearman's correlation tests, where appropriate. Age, household income, parents' education, saliva flow and pH did not differ among groups. Waist circumference and subscapular skinfold differed significantly between normal-weight and obese groups; only waist circumference showed significant correlation with BMI in all groups. pH increased significantly from US to SS in all groups; but flow rate increased from US to SS only in normal-weight and overweight groups. Total protein, amylase, urea, phosphate, triglyceride and calcium concentrations did not differ among groups. However, urea, phosphate and calcium concentrations differed significantly between US and SS in the normal-weight and overweight groups, with the lowest values for SS. In the overweight group, total protein also differed between saliva samples and obese group showed no difference in biochemical parameters between US and SS. Finally, some salivary characteristics may vary among normal-weight, overweight and obese children; thus, future studies in a larger sample are needed to fully understand salivary secretion and composition of these subjects.

  2. Advances in Thick Film Conductors for Microwave Integrated Circuits

    OpenAIRE

    Wilson, Larry K.; Rich, Debbie D.; Rich, Phil W.; R. Wayne Johnson

    1980-01-01

    New conductor pastes have made possible great improvements in the loss characteristics of thick film microwave integrated circuits. This paper presents data on the microwave characteristics of transmission structures made from newly developed copper, silver and gold conductor pastes on alumina and garnet substrates. The resistivity and microstructure for each conductor material was examined for correlation with microwave properties. These data show that thick film circuits can give excellent ...

  3. Prediction of UHPFRC panels thickness subjected to aircraft engine impact

    OpenAIRE

    Thai, Duc-Kien; Kim, Seung-Eock

    2016-01-01

    In the practical design of nuclear building structures subjected to an aircraft crash, the structures are required to prevent scabbing and perforation. NEI 07-13 provided the formulas to predict the minimum reinforced concrete (RC) wall thickness to prevent the local damage caused by aircraft engine impact. However, these formulas may not be suitable for predicting the thickness of the ultra-high performance fiber reinforced concrete (UHPFRC) wall. In this study, the local damage of a UHPFRC ...

  4. Minimum Plate Thickness in High-Speed Craft

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    The minimum plate thickness requirements specified by the classification societies for high-speed craft are supposed to ensure adequate resistance to impact loads such as collision with floating objects and objects falling on the deck. The paper presents analytical methods of describing such impact...... phenomena and proposes performance requirements instead of thickness requirements for hull panels in high-speed craft made of different building materials....

  5. Role of obesity on the thickness of primary cutaneous melanoma.

    Science.gov (United States)

    Skowron, F; Bérard, F; Balme, B; Maucort-Boulch, D

    2015-02-01

    Thick primary cutaneous melanoma (PCM) is associated with older age, male sex, being single, a low educational level, self-detection and general practice detection, nodular melanoma (NM) and acral lentiginous melanoma (ALM) types; and are found in the head-neck and lower limb locations. Obesity plays a direct role on melanoma tumour growth, as it has been shown in animal models, but its role in the thickness of PCM remains unknown. We investigated the impact of obesity on the thickness of invasive PCM. A cross-sectional study was performed in a prospective cohort for which we collected several clinical and histological data already known to be associated with thick PCM and the Body Mass Index from new cases of invasive PCM which were referred to the dermatology department in Valence. Four hundred and twenty-seven patients were studied. In an univariate analysis, thick PCM was associated with low educational level, obesity, identification by the patient or the general practitioner (GP), location on the cephalic extremity, in a non-visible area of the body, the NM and ALM type, and an ulceration. In a multivariate analysis, NM, ulceration, topography of the melanoma and identification of the melanoma by the patient or GP were significantly associated with thick melanoma. When including only clinical features in the model, low educational level, mode of melanoma identification and obesity were significantly associated with a risk of thick melanoma. Obesity is a clinical independent risk factor of thick PCM. For health policies, governments should pay greater attention to detect melanoma in obese patients. Our results encourage the basic research on tumoural growth mechanisms due to obesity in melanoma. © 2014 European Academy of Dermatology and Venereology.

  6. Retinal nerve fibre layer thickness values and their associations with ...

    African Journals Online (AJOL)

    Multivariate analysis showed that thicker mean global RNFL thickness was significantly associated with younger age, shorter axial length (AL) and hyperopia (p < 0.001). Mean RNFL thickness decreased by approximately 0.11 μm per year of aging life, and by 1.02 μm for each 1-mm of axial elongation. There was a 0.62 μm ...

  7. Enamel thickness in Asian human canines and premolars

    OpenAIRE

    Feeney, Robin N. M.; Zermeno, John P.; Reid, Donald J.; et al.

    2010-01-01

    Dental enamel thickness continues to feature prominently in anthropological studies of ape and human evolution, as well as studies of preventative oral care and treatment. Traditional studies of enamel thickness require physical sectioning of teeth for linear and scaled measurements. Recent applications of microtomographic imaging allow scientists to employ larger and more diverse samples, including global samples of recent humans as well as fossil hominin teeth. Unfortunately, little is know...

  8. Dilatation and curettage effect on the endometrial thickness.

    Science.gov (United States)

    Davar, Robab; Dehghani Firouzabadi, Razieh; Chaman Ara, Kefayat

    2013-04-01

    Endometrial receptivity is required for successful implantation and pregnancy. Despite the remaining controversy, many studies have shown that ultrasonographic endometrial thickness can be considered as an indicator of endometrial receptivity. The study objective was to investigate the effect of dilatation and curettage on the endometrial thickness. Enrolled in the study were 444 patients visited in Obstetrics & Gynecology clinic of Shahid Sadoughi hospital between Jan. 2011 to Sep. 2012. Only patients whose menstrual cycle was regular were included in study. Patients with myoma, adenomyosis, endometrial polyps or other uterine anomaly, those who smoked, whose BMI was greater than 30 and who were taking medications that could affect endometrial thickness were excluded. Endometrial thickness was measured one day before evolution (n = 444) and 5-7 days after it (n = 444) using transvaginal ultrasonography. The endometrial thicknesses were correlated to the patients' history of dilatation and curettage. Data analysis was done through SPSS software version 16 and using descriptive statistics, independent T-test and Anova. Endometrial thickness in patients who had 0, 1, 2, 3 and 4 D&C were 10.00 ± 0.58, 9.83 ± 0.47, 8.90 ± 0.92, 7.42 ± 0.18 and 7.40 ± 0.07, respectively one day before ovulation (spearman's correlation coefficient = -0.33) and 10.62 ± 0.68, 9.64 ± 0.49, 8.48 ± 0.96, 6.32 ± 0.15 and 6.90 ± 0.04, respectively, 5-7 days after ovulation (spearman's correlation coefficient = -0.66) estradiol and progesterone levels, measured in the day of 2nd ultrasonography had not statistic relation with endometrial thickness (P = 0.27 and 0.31). The relation of endometrial thickness and age was not significant (P = 0.54 and 0.06). Dilatation and curettage has a significant effect on the endometrial thinning.

  9. The effect of strabismus surgery on choroidal thickness.

    Science.gov (United States)

    Inan, Kamil; Niyaz, Leyla

    2017-09-07

    To determine the effects of strabismus surgery on choroidal thickness. This was a prospective randomized study. The measurements of subfoveal and macular choroidal thickness of patients who underwent strabismus surgery were obtained by enhanced depth imaging optic coherence tomography. The patients were grouped as patients who had 1 horizontal muscle surgery (group 1), 1 oblique muscle surgery (group 2), 2 horizontal muscle surgeries (group 3), or 1 horizontal and 1 oblique muscle surgery (group 4). Choroidal thickness of the patients was measured preoperatively and on the postoperative first day, second week, first month, and third month. Choroidal thickness was measured at subfoveal area (S) and at the nasal (N1, N2) and temporal (T1, T2) fovea with 500-μm intervals. The average age of the 37 patients was 15.59 ± 13.84 years. In preoperative and postoperative first day comparison, a decrease in choroidal thickness was found in all areas in group 1. In group 2, a significant decrease was found in N2, N1, and S values. In group 3, a significant decrease was found in N2, N1, and T2 values. In group 4, a significant decrease was found in N1 value. The second week comparison of all groups showed significant postoperative decrease in choroidal thickness in all areas. On the postoperative first month, a significant decrease in choroidal thickness was found only in the subfoveal area of group 1 and the N1 area of group 2. At the postoperative third month, there was no change in any group. Strabismus surgery causes a decrease in choroidal thickness in the early postoperative period.

  10. Ex vivo thickness measurement of cartilage covering the temporomandibular joint.

    Science.gov (United States)

    Mirahmadi, Fereshteh; Koolstra, Jan Harm; Lobbezoo, Frank; van Lenthe, G Harry; Everts, Vincent

    2017-02-08

    Articular cartilage covers the temporomandibular joint (TMJ) and provides smooth and nearly frictionless articulation while distributing mechanical loads to the subchondral bone. The thickness of the cartilage is considered to be an indicator of the stage of development, maturation, aging, loading history, and disease. The aim of our study was to develop a method for ex vivo assessment of the thickness of the cartilage that covers the TMJ and to compare that with two other existing methods. Eight porcine TMJ condyles were used to measure cartilage thickness. Three different methods were employed: needle penetration, micro-computed tomography (micro-CT), and histology; the latter was considered the gold standard. Histology and micro-CT scanning results showed no significant differences between thicknesses throughout the condyle. Needle penetration produced significantly higher values than histology, in the lateral and anterior regions. All three methods showed the anterior region to be thinner than the other regions. We concluded that overestimated thickness by the needle penetration is caused by the penetration of the needle through the first layer of subchondral bone, in which mineralization is less than in deeper layers. Micro-CT scanning method was found to be a valid method to quantify the thickness of the cartilage, and has the advantage of being non-destructive. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Parametric Investigation of Optimum Thermal Insulation Thickness for External Walls

    Directory of Open Access Journals (Sweden)

    Omer Kaynakli

    2011-06-01

    Full Text Available Numerous studies have estimated the optimum thickness of thermal insulation materials used in building walls for different climate conditions. The economic parameters (inflation rate, discount rate, lifetime and energy costs, the heating/cooling loads of the building, the wall structure and the properties of the insulation material all affect the optimum insulation thickness. This study focused on the investigation of these parameters that affect the optimum thermal insulation thickness for building walls. To determine the optimum thickness and payback period, an economic model based on life-cycle cost analysis was used. As a result, the optimum thermal insulation thickness increased with increasing the heating and cooling energy requirements, the lifetime of the building, the inflation rate, energy costs and thermal conductivity of insulation. However, the thickness decreased with increasing the discount rate, the insulation material cost, the total wall resistance, the coefficient of performance (COP of the cooling system and the solar radiation incident on a wall. In addition, the effects of these parameters on the total life-cycle cost, payback periods and energy savings were also investigated.

  12. Bayesian inference of ice thickness from remote-sensing data

    Science.gov (United States)

    Werder, Mauro A.; Huss, Matthias

    2017-04-01

    Knowledge about ice thickness and volume is indispensable for studying ice dynamics, future sea-level rise due to glacier melt or their contribution to regional hydrology. Accurate measurements of glacier thickness require on-site work, usually employing radar techniques. However, these field measurements are time consuming, expensive and sometime downright impossible. Conversely, measurements of the ice surface, namely elevation and flow velocity, are becoming available world-wide through remote sensing. The model of Farinotti et al. (2009) calculates ice thicknesses based on a mass conservation approach paired with shallow ice physics using estimates of the surface mass balance. The presented work applies a Bayesian inference approach to estimate the parameters of a modified version of this forward model by fitting it to both measurements of surface flow speed and of ice thickness. The inverse model outputs ice thickness as well the distribution of the error. We fit the model to ten test glaciers and ice caps and quantify the improvements of thickness estimates through the usage of surface ice flow measurements.

  13. The relationship between CPAP usage and corneal thickness.

    Directory of Open Access Journals (Sweden)

    Ethem Gelir

    Full Text Available The purpose of this study was to determine whether there is a correlation between CPAP usage and corneal thickness in patients with sleep disordered breathing. Full-night polysomnography (PSG recordings were collected. Ten patients had undergone PSG recordings with continuous positive airway pressure (CPAP, and seven patients had undergone PSG recordings without CPAP. We measured corneal thickness by ultrasonic pachymeter before sleep and ten minutes after waking. We also measured visual acuity with a routine ophthalmologic eye chart before and after sleep. We asked patients to fill out a post-sleep questionnaire to get their subjective opinions. In the without-CPAP group, corneal thickness increased significantly during sleep in both eyes (left, p = 0.0025; right, p0.05 for both left and right cornea. There was no significant difference in visual acuity tests (p>0.05 for both left and right eye between the two groups. According to our results, there is a significant increase in corneal thickness in the without-CPAP group. Our data show that a low percentage of Rapid Eye Movement (REM sleep may cause an increase in corneal thickness, which can indicate poor corneal oxygenation. In fact, many sleep-disordered breathing (SDB patients have low REM. Since a contact lens may cause low corneal oxygenation, SDB patients with contact lenses should be monitored carefully for their corneal thickness.

  14. Mechanical properties of F82H plates with different thicknesses

    Energy Technology Data Exchange (ETDEWEB)

    Sakasegawa, Hideo, E-mail: sakasegawa.hideo@jaea.go.jp; Tanigawa, Hiroyasu

    2016-11-01

    Highlights: • Mass effect, homogeneity, and anisotropy in mechanical properties were studied. • Thickness dependence of tensile property was not observed. • Thickness dependence of Charpy impact property was observed. • Appropriate mechanical properties were obtained using an electric furnace. - Abstract: Fusion DEMO reactor requires over 11,000 tons of reduced activation ferritic/martensitic steel and it is indispensable to develop the manufacturing technology for producing large-scale components of DEMO blanket with appropriate mechanical properties. This is because mechanical properties are generally degraded with increasing production volume. In this work, we focused mechanical properties of F82H–BA12 heat which was melted in a 20 tons electric arc furnace. Plates with difference thicknesses from 18 to 100 mm{sup t} were made from its ingot through forging and hot-rolling followed by heat treatments. Tensile and Charpy impact tests were then performed on plates focusing on their homogeneity and anisotropy. From the result, their homogeneity and anisotropy were not significant. No obvious differences were observed in tensile properties between the plates with different thicknesses. However, Charpy impact property changed with increasing plate thickness, i.e. the ductile brittle transition temperature of a 100 mm{sup t} thick plate was higher than that of the other thinner plates.

  15. High order shear horizontal modes for minimum remnant thickness.

    Science.gov (United States)

    Belanger, Pierre

    2014-04-01

    Thickness mapping in aging structures suffering from corrosion is challenging especially when the structure is only partially accessible. In plates the high order shear horizontal guided wave modes all have a cutoff frequency thickness product below which they cannot propagate. This property is potentially attractive to estimate the minimum remnant thickness between two transducers. When using a source and a sensor array it is possible to control the number of modes being excited and the size of the region interrogated by the technique. Finite element simulations were used to show that by exciting multiple guided wave modes simultaneously and identifying which modes are received by a sensor array it is possible to estimate the minimum remaining thickness along the propagation path. Initial experimental results showed excellent agreement with the finite element simulations when the plate is uniform and with a thickness reduction between the source and the sensor arrays the minimum remnant thickness was underestimated by approximately 20%. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Crustal thickness investigation on three broadband stations in Northern Sumatra

    Science.gov (United States)

    Anggono, T.; Syuhada; Soedjatmiko, B.; Amran, A.

    2017-04-01

    We present a preliminary result of crustal thickness in Northern Sumatra from receiver function analysis and grid search. Total of 111 teleseismic events from three broadband stations (TPTI, KCSI, and BSI) of IA-Network were used to calculate the receiver functions. We identified direct P and S arrival from the receiver function. Converted phases Ps were relatively clear for all three broadband stations. Ps-P time was estimated about 2 - 3 s, 2 s, and 5 - 6 s for station TPTI, KCSI, and BSI, respectively. We applied H-k stacking method to obtain crustal thickness and Vp/Vs ratio beneath the three broadband stations. At station TPTI, we obtained the crustal thickness is about 19.54 ± 3.84 km, Vp/Vs ratio is about 1.73 ± 0.14. At station KCSI, the crustal thickness was estimated to be 37.07 ± 4.47 km, Vp/Vs ratio is about 1.84 ± 0.10. At station BSI, which is located to the north of these two stations, the crustal thickness was estimated to be 40.56 ± 2.26 km, Vp/Vs ratio is about 1.81 ± 0.05. These results show relatively large variation of crustal thickness in the Northern Sumatra.

  17. Magic thickness of Bi films on the Si(111) surfac

    Science.gov (United States)

    Saito, Mineo; Takahisa, Ohno; Miyazaki, Tsuyoshi

    2004-03-01

    Stable films having specific layer thickness, which is called magic layer thickness, were reported for some metal films on Si(111). The 2D growth is achieved at this thickness; as a result, very flat films are grown. This behavior observed in low temperatures was attributed to the quantum size effect, which originates from the electron confinement in the film thickness direction. Recently the magic layer thickness was observed even at room temperature for Bi films on Si (111) surface, which raises a question as to what is the origin of this prominent stability. To answer this question, we perform first-principle calculation based on the density functional theory within the generalized gradient approximation. We first study 012 Bi film on Si (111) surface. The calculation on the energy difference between the N and N-1 layers shows that the films with even-number layer heights are stable at room temperature. In even-number layer films, each of two layers are found to be bonded. It is concluded that this pairing structure is the origin of the stability at room temperature. Therefore the magic thickness is not due to the quantum size effect. This research was done in "Frontier Simulation Software for Industrial Science" project supported by IT program of Ministry of Education, Culture, Sports, Science and Technology.

  18. The acute effect of pseudoephedrine on choroidal thickness.

    Science.gov (United States)

    Ovet, G; Alpfidan, I; Sakarya, Y; Sakarya, R; Ozcimen, M; Göktaş, S; Erdoğan, E

    2016-01-01

    To investigate the acute effects of pseudoephedrine (PE) on choroidal thickness in healthy young patients. Fifty patients with nasal and sinus congestion who were prescribed 60 mg oral PE at the otolaryngology department were recruited for this study. The enhanced depth imaging (EDI) optic coherence tomography (OCT) (Spectralis OCT; Heidelberg Engineering, Heidelberg, Germany) choroidal thickness measurements were performed at baseline and 1, 3 and 6 hours at 7 points. The right eyes of 50 healthy subjects (22 women and 28 men) were included in this study. The mean choroidal thickness at fovea was 293.12 μm, 279.80 μm, 295.80 μm, and 294.52 μm at baseline, 1, 3 and 6 hours respectively. A significant reduction in choroidal thickness versus baseline was observed at all points at 1 hour. The choroidal thickness decreased 1 hour after oral administration of PE and returned to baseline thickness at 3 hours. We suppose that this transient decrease might be associated with vasoconstriction due to activation of sympathetic alpha adrenoceptors.

  19. Anthropometric characteristics of Pakistani school children living in Bahrain.

    Science.gov (United States)

    Musaiger, Abdulrahman O; D'Souza, Reshma

    2009-06-01

    This survey was designed to study the gender difference in physical growth of 1113 Pakistani children (646 male and 467 female) living in Bahrain and to compare growth with their Bahraini and Pakistani counterparts. Measurements of height, weight, mid-arm circumference, biceps, triceps, subscapular and suprailiac skinfold thickness were carried out using the standard methods, and the median values for height and weight were plotted against the National Center for Health Statistics (NCHS) standard charts. The median weight of the boys was below the 25th percentile rising slightly above the 25th percentile at 12 years. The median height was also below the 25th percentile touching the 25th percentile only between 10-12 and 17 years. In girls, the median weight touched the 50th percentile at 15 years, followed by a fall to the 5th percentile between 16 and 17 years of age while the median height touched the 5th percentile at 17 years of age. The median body mass index (BMI) values were above the 50th percentile between 13 and 15 years in boys, and below the 50th percentile at all ages in girls. The median triceps skinfold thickness in boys was above the 50th percentile between 10-15 and 17 years in boys and in girls it was mostly below the 50th percentile rising above 50th percentile at 14, 15 and 17 years of age. The height and weight of the study group was similar to that of children residing in Pakistan for both the genders, but lower than their Bahraini counterparts for most age groups compared. Furthermore, Pakistani boys residing in Bahrain were taller after 14 years of age and heavier after 16 years of age compared to their female counterparts.

  20. Anthropometric and Quality-of-Life Parameters in Acute Intermittent Porphyria Patients.

    Science.gov (United States)

    Jiménez-Monreal, Antonia M; Murcia, M Antonia; Gómez-Murcia, Victoria; Bibiloni, Maria Del Mar; Pons, Antoni; Tur, Josep A; Martínez-Tomé, Magdalena

    2015-07-01

    The porphyrias are a group of rare metabolic disorders. The incidence and prevalence are low because the acute intermittent porphyria (AIP) is rare. Our aim was to assess the use of anthropometric and quality-of-life parameters in porphyric patients in order to identify predictor factors that might help in characterizing AIP patients.Sixteen AIP patients from Murcia (Spain) were recruited from local health centers in 2008 and 2009. A control group of 16 healthy people was established. Body composition was assessed by bioelectrical impedance analysis (BIA) and anthropometric measurements: body weight; height; knee-heel height; waist, hip, upper arm and calf circumferences (CCs); biacromion and biiliac diameters; bicondylar and biepicondylar width; and triceps, subscapular, supraspinale, and calf skinfold thickness. Anthropometric indicators were obtained from anthropometric measurements. A quality-of-life evaluation was carried out using the EuroQol-5D (EQ-5D) questionnaire and Barthel and Katz indexes. Significant differences in means were tested by unpaired Student t test. Group differences in anthropometric measurements were tested with a 2-way analysis of variance (group × condition: age group, overweight, and adiposity degree). Relative frequencies were obtained for noncontinuous variables. Significant differences in prevalence were calculated by means of χ.AIP patients showed statistically significant differences in terms of knee-heel height, biiliac diameter, CC, triceps skinfold thickness, BIA, ponderal index, endomorphy, and ectomorphy. Only 1 quality-of-life indicator, visual analog scale, in the EQ-5D questionnaire showed significant differences between porphyric and control groups.Some anthropometric parameters and the EQ-5D questionnaire could be used to appreciate the presence or follow the evolution of the disease in AIP patients.

  1. Nutritional status and lipid profile of HIV-positive children and adolescents using antiretroviral therapy.

    Science.gov (United States)

    Contri, Patricia Viganó; Berchielli, Erica Miranda; Tremeschin, Marina Hjertquist; Negrini, Bento Vidal de Moura; Salomão, Roberta Garcia; Monteiro, Jacqueline Pontes

    2011-01-01

    To describe nutritional status, body composition and lipid profile in children and adolescents receiving protease inhibitors. Fifty-nine patients, 23 treated with protease inhibitors (group 1) and 36 not using protease inhibitors (group 2). Their dietary intake, anthropometry, bioimpedance analysis and lipid profile variables were measured. There was no difference in nutritional status or body composition between groups at the beginning of the study. After 6 months of follow-up, there was an increase in weight and height in both groups, as well as in waist circumference and subscapular skinfold thickness. In group 2, body mass index and triceps skinfold thickness adequacy were significantly higher after 6 months of follow-up. The groups had similar energy and macronutrient intake at any time point. After 6 months, group 1 had a higher cholesterol intake and group 2 had a higher fiber intake. Triglyceride serum levels were significantly different between the groups, with higher values in G1, at any time point [G1: 153 mg/dl (30-344); 138 (58-378) versus G2: 76 mg/dl (29-378); 76 (29-378)]. After 6 months of follow-up, G1 had higher LDL-cholesterol than G2 [104 mg/dl (40-142) versus 82 (42-145)]. The use of protease inhibitors, per se, does not seem to significantly interfere with anthropometric measures, body composition and food intake of HIV-infected children and adolescents. However, this antiretroviral therapy was associated with a significant increase in triglyceride and LDL-cholesterol in our subjects.

  2. Anthropometric and Quality-of-Life Parameters in Acute Intermittent Porphyria Patients

    Science.gov (United States)

    Jiménez-Monreal, Antonia M; Murcia, MAntonia; Gómez-Murcia, Victoria; Bibiloni, Maria del Mar; Pons, Antoni; Tur, Josep A.; Martínez-Tomé, Magdalena

    2015-01-01

    Abstract The porphyrias are a group of rare metabolic disorders. The incidence and prevalence are low because the acute intermittent porphyria (AIP) is rare. Our aim was to assess the use of anthropometric and quality-of-life parameters in porphyric patients in order to identify predictor factors that might help in characterizing AIP patients. Sixteen AIP patients from Murcia (Spain) were recruited from local health centers in 2008 and 2009. A control group of 16 healthy people was established. Body composition was assessed by bioelectrical impedance analysis (BIA) and anthropometric measurements: body weight; height; knee-heel height; waist, hip, upper arm and calf circumferences (CCs); biacromion and biiliac diameters; bicondylar and biepicondylar width; and triceps, subscapular, supraspinale, and calf skinfold thickness. Anthropometric indicators were obtained from anthropometric measurements. A quality-of-life evaluation was carried out using the EuroQol-5D (EQ-5D) questionnaire and Barthel and Katz indexes. Significant differences in means were tested by unpaired Student t test. Group differences in anthropometric measurements were tested with a 2-way analysis of variance (group × condition: age group, overweight, and adiposity degree). Relative frequencies were obtained for noncontinuous variables. Significant differences in prevalence were calculated by means of χ2. AIP patients showed statistically significant differences in terms of knee-heel height, biiliac diameter, CC, triceps skinfold thickness, BIA, ponderal index, endomorphy, and ectomorphy. Only 1 quality-of-life indicator, visual analog scale, in the EQ-5D questionnaire showed significant differences between porphyric and control groups. Some anthropometric parameters and the EQ-5D questionnaire could be used to appreciate the presence or follow the evolution of the disease in AIP patients. PMID:26222840

  3. Quantification of residual dentine thickness following crown preparation.

    Science.gov (United States)

    Davis, Graham R; Tayeb, Rabab A; Seymour, Kevin G; Cherukara, George P

    2012-07-01

    Pulpal response to tooth preparation is a major concern in fixed prosthodontics. Research has suggested that 2mm or more of remaining dentine is critical in protecting the pulp following tooth preparation. However, clinicians have no means of knowing dentine thickness either before or after preparation and therefore lack feedback about this important aspect of preparation quality. The aim of this project was to develop a method for measuring local dentine thickness following tooth preparation for metal ceramic crowns, in vitro, which could be used as a tool to evaluate preparation technique and instrumentation. Microtomography (XMT or micro-CT) scans were taken of extracted teeth before and after crown preparation. Local dentine thickness was defined for every voxel within the 3D tooth image as the sum of distances from that voxel to the pulp and to the anatomical surface. The method also allows the thickness of material removed to be quantified. Three-dimensional colour-coded maps of dentine thickness were generated, and the distributions of dentine thickness throughout the teeth were analysed. This was tested by a single operator on sixteen extracted upper central incisors. This method enabled clear visualisation and analysis of residual dentine thickness. In the trial, it revealed consistent over-prepared regions along the labial proximal line angles which, in a clinical case, could affect subsequent tooth and restoration longevity. All but one of the prepared teeth had regions with a residual dentine thickness of less than 1.5mm, in 6 it was less than 1.0mm and in 3 of these it was less than 0.5mm. Although ex vivo, this method can be used as a research tool to look for patterns of over- or under-preparation, leading to possible modification of technique, instrumentation and, or crown design. It is not currently possible for clinicians to know the thickness of residual dentine following crown preparation, a key factor in long term outcome. The described method

  4. Allostatic load and reduced cortical thickness in schizophrenia.

    Science.gov (United States)

    Chiappelli, Joshua; Kochunov, Peter; Savransky, Anya; Fisseha, Feven; Wisner, Krista; Du, Xiaoming; Rowland, Laura M; Hong, L Elliot

    2017-03-01

    Structural imaging studies have consistently found reduced gray matter thickness of the cerebral cortex in schizophrenia, a finding that is evident in first episode psychosis and may be progressive in some cases. Although genetic predisposition and medication effects may contribute to cortical thinning, we hypothesize that the cumulative effects of stress may represent an environmental factor impacting brain morphology in schizophrenia. We examined the relationship between allostatic load, an index of peripheral biomarkers representing the cumulative effects of stress, and cortical thickness. Allostatic load was calculated for 44 patients with schizophrenia spectrum disorders (SSD) and 33 normal controls (NC) based on 13 cardiovascular, neuroendocrine, immune, and metabolic measurements. Controlling for age, SSD had significantly elevated allostatic load as compared with NC (p=0.008). Controlling for age, whole brain average cortical thickness was lower in SSD patients compared to NC (p=0.008). However, once allostatic load was accounted for, the group difference in cortical thickness became marginal (p=0.058). Exploratory analyses on subcomponents of allostatic load suggested that elevated immune marker C-reactive protein, stress hormones, and cardiovascular indices within allostatic load were more strongly associated with reduced cortical thickness in SSD. In NC, only the association between immune marker C-reactive protein and cortical thickness was replicated. These results support the hypothesis that allostatic load may account for some of the gray matter deficits observed in schizophrenia. Among the allostatic indices, the inflammatory mechanism appears particularly relevant to cortical thickness in both schizophrenia patients and normal controls. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Thickness and Clapeyron slope of the post-perovskite boundary.

    Science.gov (United States)

    Catalli, Krystle; Shim, Sang-Heon; Prakapenka, Vitali

    2009-12-10

    The thicknesses and Clapeyron slopes of mantle phase boundaries strongly influence the seismic detectability of the boundaries and convection in the mantle. The unusually large positive Clapeyron slope found for the boundary between perovskite (Pv) and post-perovskite (pPv) (the 'pPv boundary') would destabilize high-temperature anomalies in the lowermost mantle, in disagreement with the seismic observations. Here we report the thickness of the pPv boundary in (Mg(0.91)Fe(2+)(0.09))SiO(3) and (Mg(0.9)Fe(3+)(0.1))(Al(0.1)Si(0.9))O(3) as determined in a laser-heated diamond-anvil cell under in situ high-pressure (up to 145 GPa), high-temperature (up to 3,000 K) conditions. The measured Clapeyron slope is consistent with the D'' discontinuity. In both systems, however, the pPv boundary thickness increases to 400-600 +/- 100 km, which is substantially greater than the thickness of the D'' discontinuity (<30 km). Although the Fe(2+) buffering effect of ferropericlase could decrease the pPv boundary thickness, the boundary may remain thick in a pyrolitic composition because of the effects of Al and the rapid temperature increase in the D'' layer. The pPv boundary would be particularly thick in regions with an elevated Al content and/or a low Mg/Si ratio, reducing the effects of the large positive Clapeyron slope on the buoyancy of thermal anomalies and stabilizing compositional heterogeneities in the lowermost mantle. If the pPv transition is the source of the D'' discontinuity, regions with sharp discontinuities may require distinct compositions, such as a higher Mg/Si ratio or a lower Al content.

  6. Enamel thickness after preparation of tooth for porcelain laminate.

    Directory of Open Access Journals (Sweden)

    Ayoub Pahlevan

    2014-08-01

    Full Text Available In this investigation the thickness of enamel in the gingival, middle, and incisal thirds of the labial surface of the anterior teeth were measured regarding preparation of the teeth for porcelain laminate veneers.Part one, 20 extracted intact human maxillary central and lateral incisors ten of each were selected. The teeth were imbedded in autopolimerize acrylic resin. Cross section was preformed through the midline of the incisal, middle and cervical one-third of the labial surface of the teeth. The samples were observed under reflected stereomicroscope and the thickness of enamel was recorded. Part II, the effect of different types of preparation on dentin exposure was evaluated. Thirty maxillary central incisor teeth were randomly divided into two groups: A: Knife-edge preparation. B: Chamfer preparation. All samples were embedded in autopolimerize acrylic resin using a silicon mold. The samples were cut through the midline of the teeth. The surface of the samples were polished and enamel and dentin were observed under the stereomicroscope.Data were analyzed by ANOVA-one way test. The results of this study showed that the least enamel thickness in the central incisor was 345 and in lateral incisor is 235 μ this thickness is related to the one-third labial cervical area. Maximum thickness in maxillary central and lateral incisors in the one-third labial incisal surface was 1260 μ and 1220μ, respectively. In the second part of the study, the tendency of dentinal exposure was shown with the chamfer preparation, but no dentinal exposure was found in the knife-edge preparation. The differences between groups were significant (p<0.05.The knowledge of enamel thickness in different part of labial surface is very important. The thickness of enamel in the gingival area does not permit a chamfer preparation. The knife edge preparation is preferable in gingival area.

  7. Increase in average foveal thickness after internal limiting membrane peeling

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    Kumagai K

    2017-04-01

    Full Text Available Kazuyuki Kumagai,1 Mariko Furukawa,1 Tetsuyuki Suetsugu,1 Nobuchika Ogino2 1Department of Ophthalmology, Kami-iida Daiichi General Hospital, 2Department of Ophthalmology, Nishigaki Eye Clinic, Aichi, Japan Purpose: To report the findings in three cases in which the average foveal thickness was increased after a thin epiretinal membrane (ERM was removed by vitrectomy with internal limiting membrane (ILM peeling.Methods: The foveal contour was normal preoperatively in all eyes. All cases underwent successful phacovitrectomy with ILM peeling for a thin ERM. The optical coherence tomography (OCT images were examined before and after the surgery. The changes in the average foveal (1 mm thickness and the foveal areas within 500 µm from the foveal center were measured. The postoperative changes in the inner and outer retinal areas determined from the cross-sectional OCT images were analyzed.Results: The average foveal thickness and the inner and outer foveal areas increased significantly after the surgery in each of the three cases. The percentage increase in the average foveal thickness relative to the baseline thickness was 26% in Case 1, 29% in Case 2, and 31% in Case 3. The percentage increase in the foveal inner retinal area was 71% in Case 1, 113% in Case 2, and 110% in Case 3, and the percentage increase in foveal outer retinal area was 8% in Case 1, 13% in Case 2, and 18% in Case 3.Conclusion: The increase in the average foveal thickness and the inner and outer foveal areas suggests that a centripetal movement of the inner and outer retinal layers toward the foveal center probably occurred due to the ILM peeling. Keywords: internal limiting membrane, optical coherence tomography, average foveal thickness, epiretinal membrane, vitrectomy

  8. Thickness effect on flexural strength of natural stone

    Science.gov (United States)

    Bellopede, Rossana; Marini, Paola; Castelletto, Eleonora

    2016-04-01

    Few scientific works deal with size effect on mechanical resistance in the case of stone, but for the concrete size effect has been widely verified. In fact, the stone size effect is not always ruled by well-known statistical laws as Weibull because of the intrinsic complex structure and features of the materials analysed. Previous studies on natural stone size effect have been made mainly taking into account compression strength. However, flexural strength test under concentrated load, according EN12372, is applied to assess the mechanical resistance of stone and it is well correlated with the petrographic properties of stone. For this reason, to further investigate the size effect on stone , this research analyses the variation of mechanical resistance in relation to thickness of the specimens, taking into account the petrographic characteristics (mineralogical composition, heterogeneity, anisotropy, porosity)of different kinds of rock. From previous studies on 15 different stones (Bellopede et al. 2015) it was observed a negligible values variation for different thickness and a data scattering caused by: intrinsic properties (porosity and structure), defects distribution (fractures, cracks, voids), heterogeneity characterizing each specimen. According to EN 12372:2006, the suggested dimensions for the determination of flexural strength under concentrated load are 50x50x300mm. Other dimensions are possible, but the following requirement need to be fulfilled. The thickness should be minimum 25mm and maximum 100 mm, the width should be within 50 mm and 3 times the thickness and the distance between the supporting rollers span should be 5 times the thickness. In this research, in order to further investigate the thickness effect even in relation with the stone structure and heterogeneity, eight different stones have been tested: four with anisotropic features and four homogeneous. The distance between the support knife was equal to 2/3 to specimens length. The

  9. Measurement of compressed breast thickness by optical stereoscopic photogrammetry

    Energy Technology Data Exchange (ETDEWEB)

    Tyson, Albert H.; Mawdsley, Gordon E.; Yaffe, Martin J. [Room S657, Imaging Research, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada)

    2009-02-15

    The determination of volumetric breast density (VBD) from mammograms requires accurate knowledge of the thickness of the compressed breast. In attempting to accurately determine VBD from images obtained on conventional mammography systems, the authors found that the thickness reported by a number of mammography systems in the field varied by as much as 15 mm when compressing the same breast or phantom. In order to evaluate the behavior of mammographic compression systems and to be able to predict the thickness at different locations in the breast on patients, they have developed a method for measuring the local thickness of the breast at all points of contact with the compression paddle using optical stereoscopic photogrammetry. On both flat (solid) and compressible phantoms, the measurements were accurate to better than 1 mm with a precision of 0.2 mm. In a pilot study, this method was used to measure thickness on 108 volunteers who were undergoing mammography examination. This measurement tool will allow us to characterize paddle surface deformations, deflections and calibration offsets for mammographic units.

  10. Eggshell thickness and DDE residue levels in vlulture eggs

    Science.gov (United States)

    Kiff, L.F.; Peakall, David B.; Morrison, M.L.; Wilbur, S.R.; Wilbur, Sanford R.; Jackson, Jerome A.

    1983-01-01

    Post-DDT (post-1947) eggshell thickness was examined in samples of Turkey Vulture, Black Vulture, and Crested Caracara eggs from several parts of the United States. Highly significant post-DDT decreases in eggshell thickness indices of at least 10 percent were found in Turkey Vulture eggs from California, Florida, and Texas and in Black Vulture eggs from Texas and Florida. Over one-third of the Black VUlture eggs and about 30 percent of the Turkey Vulture eggs from Texas showed thinning exceeding 20 percent, a level associated with reproductive failure and population decline in other species. A strong negative correlation was found between eggshell thickness indices and DDE residues extracted from eggshell membranes in California and Texas samples of Turkey Vulture eggs and in Texas Black Vulture eggs. Crested Caracara eggs from Texas and Florida showed mean changes in eggshell thickness indices of only -5.6 and -8.2 percent, respectively, although thinning in a few eggs from both states exceeded 20 percent. Most of the post-DDT Old World vulture eggs examined appeared to be of normal thickness, with low DDE residue levels in eggshell membranes; but single eggs of Egyptian Vulture from India, Cinereous Vulture from Spain, and White-headed Vulture from Zambia showed apparent thinning. Further monitoring of vulture populations in tropical regions, where DDT use is still increasing, is recommended.

  11. Smoking influences on the thickness of marginal gingival epithelium

    Directory of Open Access Journals (Sweden)

    Villar Cristina Cunha

    2003-01-01

    Full Text Available Smoking patients show reduction of inflammatory clinical signs that might be associated with local vasoconstriction and an increased gingival epithelial thickness. The purpose of this work was to evaluate the thickness of the marginal gingival oral epithelium in smokers and non-smokers, with clinically healthy gingivae or with gingivitis. Twenty biopsies were obtained from four different groups. Group I: non-smokers with clinically healthy gingivae (n = 5. Group II: non-smokers with gingivitis (n = 5. Group III: smokers with clinically healthy gingivae (n = 5. Group IV: smokers with gingivitis (n = 5. These biopsies were histologically processed, serially sectioned at 5 mm, stained with H. E., and examined by image analysis software (KS400, which was used to perform the morphometric evaluation and the quantification of the major epithelial thickness, the epithelial base thickness and the external and internal epithelial perimeters. Differences between the four groups were analyzed using ANOVA test and Tukey's test. The criteria for statistical significance were accepted at the probability level p < 0.05. A greater epithelial thickness was observed in smokers independent of the gingival health situation.

  12. Assessing Errors Inherent in OCT-Derived Macular Thickness Maps

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    Daniel Odell

    2011-01-01

    Full Text Available SD-OCT has become an essential tool for evaluating macular pathology; however several aspects of data collection and analysis affect the accuracy of retinal thickness measurements. Here we evaluated sampling density, scan centering, and axial length compensation as factors affecting the accuracy of macular thickness maps. Forty-three patients with various retinal pathologies and 113 normal subjects were imaged using Cirrus HD-OCT. Reduced B-scan density was associated with increased interpolation error in ETDRS macular thickness plots. Correcting for individual differences in axial length revealed modest errors in retinal thickness maps, while more pronounced errors were observed when the ETDRS plot was not positioned at the center of the fovea (which can occur as a result of errant fixation. Cumulative error can exceed hundreds of microns, even under “ideal observer” conditions. This preventable error is particularly relevant when attempting to compare macular thickness maps to normative databases or measuring the area or volume of retinal features.

  13. Human tissue thickness measurements from excised sleeve gastrectomy specimens.

    Science.gov (United States)

    Rawlins, Logan; Rawlins, Melissa P; Teel, Donovan

    2014-03-01

    Little basic science data exists regarding the thickness of transected stomach as the limits of smaller gastric sleeves are created closer to the lesser curvature in laparoscopic sleeve gastrectomy (SG). We sought to determine the tissue thickness trends along the staple line and examine what factors might predispose to thicker tissue. This was a single-center, single-surgeon nonrandomized prospective study of patients undergoing SG. Excised SG specimens, with patient consent, underwent tissue measurement at multiple predetermined locations and at the midpoint of each fired staple cartridge. After 9 months, ending in July 2012, we met our goal enrollment of 50 gastric sleeve specimens. Most of the patients were female (80 %) and white (92.5 %). Average age was 42 years (range, 19-60 years), and average body mass index (BMI) was 49 kg/m(2) (range, 34-82 kg/m(2)). Tissue thickness was significantly different (p 50 kg/m(2)) and gender (male) are associated with increased tissue thickness, but only in the antrum. Surgeons should consider using a thicker staple load, such as black, when these factors are present. Also, significant changes in tissue thickness at the fourth and fifth staple fires suggest stepwise alteration in staple cartridge color selection.

  14. Thin dielectric film thickness determination by advanced transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Diebold, A.C.; Foran, B.; Kisielowski, C.; Muller, D.; Pennycook, S.; Principe, E.; Stemmer, S.

    2003-09-01

    High Resolution Transmission Electron Microscopy (HR-TEM) has been used as the ultimate method of thickness measurement for thin films. The appearance of phase contrast interference patterns in HR-TEM images has long been confused as the appearance of a crystal lattice by non-specialists. Relatively easy to interpret crystal lattice images are now directly observed with the introduction of annular dark field detectors for scanning TEM (STEM). With the recent development of reliable lattice image processing software that creates crystal structure images from phase contrast data, HR-TEM can also provide crystal lattice images. The resolution of both methods was steadily improved reaching now into the sub Angstrom region. Improvements in electron lens and image analysis software are increasing the spatial resolution of both methods. Optimum resolution for STEM requires that the probe beam be highly localized. In STEM, beam localization is enhanced by selection of the correct aperture. When STEM measurement is done using a highly localized probe beam, HR-TEM and STEM measurement of the thickness of silicon oxynitride films agree within experimental error. In this paper, the optimum conditions for HR-TEM and STEM measurement are discussed along with a method for repeatable film thickness determination. The impact of sample thickness is also discussed. The key result in this paper is the proposal of a reproducible method for film thickness determination.

  15. Measurement of compressed breast thickness by optical stereoscopic photogrammetry.

    Science.gov (United States)

    Tyson, Albert H; Mawdsley, Gordon E; Yaffe, Martin J

    2009-02-01

    The determination of volumetric breast density (VBD) from mammograms requires accurate knowledge of the thickness of the compressed breast. In attempting to accurately determine VBD from images obtained on conventional mammography systems, the authors found that the thickness reported by a number of mammography systems in the field varied by as much as 15 mm when compressing the same breast or phantom. In order to evaluate the behavior of mammographic compression systems and to be able to predict the thickness at different locations in the breast on patients, they have developed a method for measuring the local thickness of the breast at all points of contact with the compression paddle using optical stereoscopic photogrammetry. On both flat (solid) and compressible phantoms, the measurements were accurate to better than 1 mm with a precision of 0.2 mm. In a pilot study, this method was used to measure thickness on 108 volunteers who were undergoing mammography examination. This measurement tool will allow us to characterize paddle surface deformations, deflections and calibration offsets for mammographic units.

  16. RF magnetron sputtering of thick film amorphous beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Burt, R.J.; Meyer, S.F.; Hsieh, E.J.

    1979-09-19

    Thick film coatings of beryllium, needed for the low-Z ablator layer in proposed laser fusion targets, have been prepared using high rate magnetron rf sputtering. The requirements for these Be coatings include thicknesses from 5 to 50 ..mu..m, complete freedom from surface defects, and an average surface roughness of 100 nm or less. We have sputtered very smooth, dense, thick Be films with surface roughness less than 100 nm. X-ray diffraction analysis of impurity doped films indicates an amorphous-like structure. Impurity stabilized amorphous Be with smooth surfaces is reported on both cooled copper and higher temperature glass substrates. The sputtering parameters (substrate temperature, deposition rate, argon pressure, and impurity gas levels) affecting surface roughness and film structure are discussed in terms of SEM, AES, and x-ray diffraction results.

  17. Vision-based surface defect inspection for thick steel plates

    Science.gov (United States)

    Yun, Jong Pil; Kim, Dongseob; Kim, KyuHwan; Lee, Sang Jun; Park, Chang Hyun; Kim, Sang Woo

    2017-05-01

    There are several types of steel products, such as wire rods, cold-rolled coils, hot-rolled coils, thick plates, and electrical sheets. Surface stains on cold-rolled coils are considered defects. However, surface stains on thick plates are not considered defects. A conventional optical structure is composed of a camera and lighting module. A defect inspection system that uses a dual lighting structure to distinguish uneven defects and color changes by surface noise is proposed. In addition, an image processing algorithm that can be used to detect defects is presented in this paper. The algorithm consists of a Gabor filter that detects the switching pattern and employs the binarization method to extract the shape of the defect. The optics module and detection algorithm optimized using a simulator were installed at a real plant, and the experimental results conducted on thick steel plate images obtained from the steel production line show the effectiveness of the proposed method.

  18. Does vitamin D affect femoral cartilage thickness? An ultrasonographic study.

    Science.gov (United States)

    Malas, Fevziye Unsal; Kara, Murat; Aktekin, Lale; Ersöz, Murat; Ozçakar, Levent

    2014-09-01

    This study aims to investigate the association between vitamin D levels and distal femoral cartilage thickness in healthy subjects. Eighty patients who were admitted to our outpatient clinic between May and July 2013 were classified into three subgroups according to their 25-OH vitamin D levels of vitamin D deficiency (vitamin D levels and US measurements in the severe vitamin D deficiency group at RLC (r = 444, p = 0.020), LMC (r = 357, p = 0.067), and LLC (r = 568, p = 0.002). Low levels of vitamin D seem to affect the femoral cartilage thickness, adversely. Further studies are necessary to ascertain the clinical relevance of this change in cartilage thickness and whether vitamin D supplementation can reverse the cartilage thinning process or the allied clinical symptoms in the course of knee osteoarthritis.

  19. Study on thickness distribution of thermoformed medical PVC blister

    Science.gov (United States)

    Li, Yiping

    2017-08-01

    Vacuum forming has many advantages over other plastic forming processes due to its cost effectiveness, time efficiency, higher product precision, and more design flexibility. Nevertheless, when pressures greater than the atmospheric value are required to force the thermo-plastic into more intimate contact with the mold surface, pressure forming is a better choice. This paper studies the process of air-pressure thermoforming of plastic sheet, and focuses on medical blister PVC products. ANSYS POLYFLOW tool is used to simulate the process and analyze the wall thickness distribution of the blister. The influence of mold parameters on the wall thickness distribution of thermoformed part is thus obtained through simulation. Increasing radius between mold and side wall at the bottom of blister and draft prove to improve the wall thickness distribution.

  20. The fire resistance of wood depending on material's thickness

    Directory of Open Access Journals (Sweden)

    Jiří Holan

    2008-01-01

    Full Text Available The paper presents the resisitance of wood against a pilot flame. The fire has negative effect on the wood and its properties. The fire and its high temperature cause a degradation of chemical components of wood. Hence the physical properties are changed and strength of the wood is decreased. The combustion velocity and the loss weight depend on the material's thickness. For tests have been chosen groups of samples with thickness of 5, 10, 15 and 20 mm. The result of submitted work is a time estimation of the fire penetration and an observation of weight losses coupled with visual changes observation of degraded samples. It have been established that with an action of the pilot flame the needed time to fire penetration is rising with rising material's thickness and at the same time the cumbustion velocity is decreasing.

  1. Orofacial contracture management outcomes following partial thickness facial burns.

    Science.gov (United States)

    Clayton, N A; Ward, E C; Maitz, P K M

    2015-09-01

    To examine clinical outcomes following non-surgical exercise for contracture management post partial thickness orofacial burn. A cohort of 229 patients with partial thickness orofacial burn was recruited over 3 years. Orofacial contracture management combining exercise and stretching was initiated within 48h of admission and continued until functional goals were consistently achieved. A second cohort of 120 healthy controls was recruited for normative comparison. Vertical and horizontal mouth opening measures were recorded at the start and completion of orofacial intervention for patients and once only for controls. At commencement of intervention, participants with orofacial burns had significantly (pcontracture management for patients with partial thickness orofacial burn. Despite this, some functional loss remained with patients demonstrating persistent reduced vertical mouth opening at conclusion of treatment compared to their healthy counterparts. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  2. Bilayer thickness mismatch controls domain size in biomimetic membranes

    Science.gov (United States)

    Heberle, Frederick A.; Petruzielo, Robin S.; Pan, Jianjun; Drazba, Paul; Kučerka, Norbert; Standaert, Robert F.; Feigenson, Gerald W.; Katsara, John

    2013-03-01

    In order to promote functionality, cells may alter the spatial organization of membrane lipids and proteins, including separation of liquid phases into distinct domains. In model membranes, domain size and morphology depend strongly on composition and temperature, but the physicochemical mechanisms controlling them are poorly understood. Theoretical work suggests a role for interfacial energy at domain boundaries, which may be driven in part by thickness mismatch between a domain and its surrounding bilayer. However, no direct evidence linking thickness mismatch to domain size in free-standing bilayers has been reported. We describe the use of Small Angle Neutron Scattering (SANS) to detect domains in simplified lipid-only models that mimic the composition of plasma membrane. We find that domain size is controlled by the degree of acyl chain unsaturation of low-melting temperature lipids, and that this size transition is correlated to changes in the thickness mismatch between coexisting liquid phases.

  3. Charge distribution dependency on gap thickness of CMS endcap RPC

    CERN Document Server

    Park, Sung Keun

    2016-01-01

    We present a systematic study of charge distribution dependency of CMS Resistive Plate Chamber (RPC) on gap thickness.Prototypes of double-gap with five different gap thickness from 1.8mm to 1.0mm in 0.2mm steps have been built with 2mm thick phenolic high-pressure-laminated (HPL) plates. The charges of cosmic-muon signals induced on the detector strips are measured as a function of time using two four-channel 400-MHz fresh ADCs. In addition, the arrival time of the muons and the strip cluster sizes are measured by digitizing the signal using a 32-channel voltage-mode front-end-electronics and a 400-MHz 64-channel multi-hit TDC. The gain and the input impedance of the front-end-electronics were 200mV/mV and 20 Ohm, respectively.

  4. Effect of thickness on silicon solar cell efficiency

    Science.gov (United States)

    Sah, C.-T.; Yamakawa, K. A.; Lutwack, R.

    1982-01-01

    A computer-aided-design study on the dependence of the efficiency peak of a back-surface field solar cell on the concentrations of the recombination and dopant impurities is presented. The illuminated current-voltage characteristics of more than 100 cell designs are obtained using the transmission line circuit model to numerically solve the Shockley equations. Using an AM 1 efficiency of 17% as a target value, it is shown that the efficiency versus thickness dependence has a broad maximum which varies by less than 1% over more than a three-to-one range of cell thicknesses from 30 to 100 microns. An optically reflecting back surface will give only a slight improvement of AM 1 efficiency, about 0.7%, in this thickness range. Attention is given to the dependence of the efficiency on patchiness across the back-surface field low-high junction in thin cells.

  5. Visual Acuity, and Macular and Peripapillary Thickness in High Myopia.

    Science.gov (United States)

    Abdolrahimzadeh, Solmaz; Parisi, Francesco; Plateroti, Andrea Maria; Evangelista, Federica; Fenicia, Vito; Scuderi, Gianluca; Recupero, Santi Maria

    2017-11-01

    To investigate best corrected visual acuity (BCVA), and choroidal and retinal thickness values between high myopes without myopic maculopathy and emmetropes. Case control study where 53 myopes with axial length (AL) above 26 mm without myopic maculopathy and 53 age-matched emmetropes with AL between 21.50 and 24.50 were included as controls. Complete ophthalmological examination and biometry were performed. Choroidal and individual retinal layer thickness maps using spectral domain optical coherence tomography were obtained in the macular and peripapillary area with enhanced depth imaging. Peripapillary retinal nerve fiber layer (pRNFL) thickness was obtained using the circular 12°diameter scan. Mean age was 31.9 ± 9.9 and 32.5 ± 9.3 years in the myopes and controls, respectively (p > 0.05). Mean BCVA was 55.32 ± 2.50 versus 57.04 ± 2.27 ETDRS letters, in the myopes and controls, respectively (p = 0.0004). AL was the principal predictive factor for macular and peripapillary CT in myopes and macular CT in controls. BCVA was not influenced by choroidal thickness (CT). BCVA positively correlated with global pRNFL, following correction for age and AL, in both groups (r = 0.38, p = 0.008 and r = 0.38, p = 0.007 in the myopic and control groups, respectively). Statistical analysis following correction for the potential confounding factors of age, gender, AL, gender, AL, macular CT, and peripapillary CT, showed no significant differences in macular and peripapillary thicknesses between the two groups. AL is the principal predictive factor for macular and peripapillary CT in high myopes without maculopathy, and CT is not an independent predictor of visual acuity. Global pRNFL thickness is the only independent predictive factor of BCVA.

  6. Correlation between Corneal Thickness and Degree of Myopic Refractory Error

    Directory of Open Access Journals (Sweden)

    A Mortazavi

    2005-01-01

    Full Text Available Background: corneal thickness is an important factor in refractive surgeries such as Radial Keratotomy (RK, Photo Refractive Keratotomy (PRK and Laser Insitu Keratomileusis (LASIK. This study evaluated the correlation between this factor and the degree of myopic refractory error. Methods: In this cross-sectional study, 224 myopic eyes (112 patients which had undergone LASIK operation were assessed. These patients had referred to Aban Eye Clinic, Isfahan, Iran, during August and September 2002. Corneal thickness was measured by ORB SCAN Topoghraphy, and cycloplegic refraction was performed with autorefratometery and retinoscopy. Suspected keratoconus cases and hyperopic patients were excluded. Results: The patients' age was 27.2 ± 1.36 in men (N = 35 and 30.13 ± 1.04 in women (N = 77. Mean value of myopic refractory error in male patients was 5.1 ± 0.24D and in female patients was 3.8 ± 0.36D. Mean of corneal thickness was 540 ± 5.25 µM and 530 ± 5.88 µM in male and female patients respectively. There was no correlation between the degree of myopia and corneal thickness in any of the patients. Also in this research, no relations between the age and myopia were found. Right eye (P > 0.5, r = 0.124 Left eye (P > 0.5, r = 0.104. Conclusion: Based on our findings, corneal thickness and myopic refectory error do not seem to have any relations. (r = 0.039, p = 0.684. Keywords: Corneal Thickness, Cornea, Myopia, LASIK, Refractory Error

  7. Association between PAPP-A and placental thickness

    Directory of Open Access Journals (Sweden)

    Elaheh Mesdaghi-nia

    2016-06-01

    Full Text Available Background: Measuring of maternal serum pregnancy-associated plasma protein-A (PAPP-A in first trimester can be a way for early detection of adverse prenatal outcome due to faulty placenta. Objective: The aim was to Determination of association between placental thickness in second trimester with low level of PAPP-A in first trimester. Materials and Methods: In this cohort study, serum PAPP-A of 187 pregnant women was measured in the first trimester of pregnancy. Patients who had PAPP-A ≤0.8 MOM were in exposed and others who had PAPP-A >0.8 defined as unexposed group. The criteria of placental thickness in ultrasound study was thickness of 4 cm or more than 50% of placental length. Results: Of 187 patients, 87 patients had PAPP-A >0.8 and 93 patients had PAPP-A ≤0.8. Women with low levels of PAPP-A in the first trimester, had an increased incidence placental thickness of 34.4%, whereas another group had about 15% (p=0.002. Also, PAPP-A levels had acceptable sensitivity and specificity for placental thickness detection (71.1% and 54.8%, respectively. Conclusion: Our study showed that serum level of PAPP-A generally was low (≤0.8 in women with a thick placenta (>4 cm or >50% of placental length. The first trimester of pregnancy measurement of PAPP-A will be more predictable for healthy placenta.

  8. Differential Effect of Bilayer Thickness on Sticholysin Activity.

    Science.gov (United States)

    Palacios-Ortega, Juan; García-Linares, Sara; Rivera-de-Torre, Esperanza; Gavilanes, José G; Martínez-Del-Pozo, Álvaro; Slotte, J Peter

    2017-10-17

    In this study, we examined the influence of bilayer thickness on the activity of the actinoporin toxins sticholysin I and II (StnI and StnII) at 25 °C. Bilayer thickness was varied using dimonounsaturated phosphatidylcholine (PC) analogues (with 14:1, 16:1, 18:1, 20:1, and 22:1 acyl chains). In addition, N-14:0-sphingomyelin (SM) was always included because StnI and StnII are SM specific. Cholesterol was also incorporated as indicated. In cholesterol-free large unilamellar vesicles (LUVs) the PC:SM molar ratio was 4:1, and when cholesterol was included, the complete molar ratio was 4:1:0.5 (PC:SM:cholesterol, respectively). Stn toxins promote bilayer leakage through pores formed by oligomerized toxin monomers. Initial calcein leakage was moderately dependent on bilayer PC acyl chain length (and thus bilayer thickness), with higher rates observed with di-16:1 and di-18:1 PC bilayers. In the presence of cholesterol, the maximum rates of calcein leakage were observed in di-14:1 and di-16:1 PC bilayers. Using isothermal titration calorimetry to study the Stn-LUV interaction, we observed that the bilayer affinity constant (Ka) peaked with LUVs containing di-18:1 PC, and was lower in shorter and longer PC acyl chain bilayers. The presence of cholesterol increased the binding affinity approximately 30-fold at the optimal bilayer thickness (di-18:1-PC). We conclude that bilayer thickness affects both functional and conformational aspects of Stn membrane binding and pore formation. Moreover, the length of the actinoporins' N-terminal α-helix, which penetrates the membrane to form a functional pore, appears to be optimal for the membrane thickness represented by di-18:1 PC.

  9. Obesity in 21-hydroxylase deficient patients

    OpenAIRE

    Cornean, R.; Hindmarsh, P; Brook, C.

    1998-01-01

    OBJECTIVES—To evaluate the natural history and timing of adiposity rebound (nadir of body mass index (BMI)) in children with congenital adrenal hyperplasia 21-hydroxylase deficiency (CYP21). 
STUDY DESIGN—A retrospective mixed longitudinal study.
METHODS—Height and changes in body composition (BMI; weight (kg)/height2 (m)), triceps and subscapular skinfolds) were analysed in 22(14 girls, eight boys) prepubertal patients with CYP21 for whom continuous anthropometric data were ...

  10. Tear Movement through a Contact Lens of Variable Thickness

    Science.gov (United States)

    Gerhart, Matthew; Anderson, Daniel

    2013-11-01

    This work is on a two-dimensional tear film with a movable porous contact lens. The inclusion of a contact lens into a tear film results in three layers: Pre-Lens Tear Film, Contact Lens, and the Post-Lens Tear Film layers. The interfaces between the contact lens and the tear films are modeled as planar interfaces. There is a free surface interface between the tear film and the outside air. The goal is analyze the effects of the spatial variability of thickness on the Post-Lens Tear Film thickness and on the fluid flow through the Contact Lens layer.

  11. MEMS-based thick film PZT vibrational energy harvester

    DEFF Research Database (Denmark)

    Lei, Anders; Xu, Ruichao; Thyssen, Anders

    2011-01-01

    We present a MEMS-based unimorph silicon/PZT thick film vibrational energy harvester with an integrated proof mass. We have developed a process that allows fabrication of high performance silicon based energy harvesters with a yield higher than 90%. The process comprises a KOH etch using...... a mechanical front side protection of an SOI wafer with screen printed PZT thick film. The fabricated harvester device produces 14.0 μW with an optimal resistive load of 100 kΩ from 1g (g=9.81 m s-2) input acceleration at its resonant frequency of 235 Hz....

  12. Thickness monitoring of optical filters for DWDM applications.

    Science.gov (United States)

    Postava, Kamil; Pistora, Jaromır; Kojima, Masashi; Kikuchi, Kazuo; Endo, Kazuhiro; Yamaguchi, Tomuo

    2003-03-24

    A method for thickness monitoring and turning-point prediction during deposition of narrow band pass optical filters (NBPF) for dense-wavelength-division-multiplexing (DWDM) applications is proposed. The method is based on a recurrent approach, with relative transmittance .tting, and includes partial coherence and monochromator bandpass e.ects. We show that the partial coherence e.ects in thin .lm structures are signi.cant and can not be neglected. The proposed method is applicable for precise thickness monitoring and deposition control of any complex multilayer coating.

  13. Self-assembled film thickness determination by focused ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Dejeu, J. [Institut UTINAM, UMR 6213 CNRS-UFC - equipe Materiaux et Surfaces Structures, Universite de Franche-Comte, UFR Sciences et Techniques, 16 route de Gray - 25030 Besancon Cedex (France)], E-mail: jerome.dejeu@univ-fcomte.fr; Salut, R. [Institut FEMTO-ST, UMR 6174 CNRS-UFC-UTBM-ENSMM, Centrale MIMENTO, Universite de Franche-Comte, 32 avenue de l' Observatoire - 25044 Besancon Cedex (France); Spajer, M. [Institut FEMTO-ST, UMR 6174 CNRS-UFC-UTBM-ENSMM, Centrale MIMENTO, Universite de Franche-Comte, 32 avenue de l' Observatoire - 25044 Besancon Cedex (France); Institut FEMTO-ST, UMR 6174 CNRS-UFC-UTBM-ENSMM, Departement d' Optique, Universite de Franche-Comte, UFR Sciences et Techniques, 16 route de Gray - 25030 Besancon Cedex (France); Membrey, F.; Foissy, A. [Institut UTINAM, UMR 6213 CNRS-UFC - equipe Materiaux et Surfaces Structures, Universite de Franche-Comte, UFR Sciences et Techniques, 16 route de Gray - 25030 Besancon Cedex (France); Charraut, D. [Institut FEMTO-ST, UMR 6174 CNRS-UFC-UTBM-ENSMM, Departement d' Optique, Universite de Franche-Comte, UFR Sciences et Techniques, 16 route de Gray - 25030 Besancon Cedex (France)

    2008-06-30

    The thickness evolution of multilayer film is investigated by focused ion beam (FIB) in the domain of polymer multilayers. This method, currently used in the modification and the characterization of integrated circuits, proves it is possible to determine the polymer film thickness. Sample cutting and its observation of the cross-section are performed in the FIB without leaving the vacuum chamber. Two main conclusions can be drawn: (1) the roughness of the film increases with the number of layer deposit, (2) the film growth changes from nonlinear (called exponential) to linear beyond 300 nm (70 layers)

  14. Thin Sea-ice Thickness Retrievals from SMAP Brightness Temperatures

    Science.gov (United States)

    Bayler, E. J.; Smith, R.

    2016-12-01

    The retrieval of thin sea-ice thicknesses has been developed for data from the European Space Agency's Soil Moisture - Ocean Salinity (SMOS) mission, employing the transition of observed surface emissivity from open water to thick sea ice. This technique is now applied to brightness temperature data from NASA's Soil Moisture Active-Passive (SMAP) mission, addressing the instrument differences between the SMOS Microwave Imaging Radiometer using Aperture Synthesis (MIRAS) and the SMAP scanning radiometer. This study demonstrates the utility of SMAP data for addressing a critical data gap for numerical prediction in polar regions, particularly as operational modeling advances toward coupled ocean-atmosphere-cryosphere modeling.

  15. Rolling method for thick slabs to remove the loose structure

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Yoshihiro; Tsuda, Osamu; Osuna, Hiroshi (Kobe Steel Ltd. (Japan). Central Research and Development Lab.); Tomonaga, Mitsuo; Saito, Shunji

    1983-10-01

    A model test was performed using coupled plasticine specimens to simulate the temperature distribution of the slab section, and a criterion was set up for closure of the inner voids in thick slabs. The most suitable conditions for closure were 300/sup 0/C in temperature difference between the center and the surface of a slab and above 0.37 in rolling shape factor, in the case of a 40% reduction. It was also found that a cooling zone width greater than 3 times the slab thickness is enough for closure.

  16. Stellar streams in the Galactic thick disk: preliminary results

    Science.gov (United States)

    Ramya, P.; Reddy, Bacham E.

    Here we report preliminary results of our study of chemical tagging of member stars of two Galactic stellar streams. Both the streams, kinematically belong to the thick disk component of the Galaxy. We analysed high resolution spectra of 42 member stars: 17 from Arcturus stream and 25 from ``AF06 stream''. The LTE (Local Thermodynamic Equilibrium) abundance analysis was performed differentially with respect to the sun. Abundance results suggest that both the streams are metal poor and enhanced in α-process elements (O, Mg, Si, Ca, Ti) very similar to the thick disk chemistry. Also, results suggest that the two streams probably did not originate by the dispersion of open clusters.

  17. Fabrication of BIT thick films patterned by proton beam writing

    Science.gov (United States)

    Yamaguchi, Masaki; Watanabe, Kazuki; Nishikawa, Hiroyuki; Masuda, Yoichiro

    2017-07-01

    In this study, we fabricated thick films with polyvinylpyrrolidone (PVP) added to bismuth titanate (Bi4Ti3O12) to form a lead-free ferroelectric material. We examined the direct patterning of these materials by using proton-beam irradiation. When 50% PVP was added to the organic source solution, the c-axis orientation was promoted and cracks were suppressed due to stress relaxation. In addition, a dot and an arbitrary-shape micro-pattern were formed on bismuth-titanate thick film by micromachining using a proton beam.

  18. Superminiature Eddy-current Transducers for Thickness Studies

    Science.gov (United States)

    Sagalakov, A. M.; Dmitriev, S. F.; Malikov, V. N.

    2017-11-01

    On the basis of the transformer type eddy-current transducer we created a measuring system which allows us to estimate the possibility of the eddy-current method application to measure the thickness of the conductive and dielectric coatings placed on the conductive base. We described the structure of the measuring system and the measurement procedure. A scheme that uses a computer as a generator and receiver of signals from windings is proposed. The article contains the data demonstrating the dependency of the amplitude part of the signal on the objects of different thickness and states the objects’ experimentally determined limits of the size that precondition the practicability of these measurements.

  19. Seismic velocity and crustal thickness inversions: Moon and Mars

    Science.gov (United States)

    Drilleau, Melanie; Blanchette-Guertin, Jean-François; Kawamura, Taichi; Lognonné, Philippe; Wieczorek, Mark

    2017-04-01

    We present results from new inversions of seismic data arrival times acquired by the Apollo active and passive experiments. Markov chain Monte Carlo inversions are used to constrain (i) 1-D lunar crustal and upper mantle velocity models and (ii) 3-D lateral crustal thickness models under the Apollo stations and the artificial and natural impact sites. A full 3-D model of the lunar crustal thickness is then obtained using the GRAIL gravimetric data, anchored by the crustal thicknesses under each Apollo station and impact site. To avoid the use of any seismic reference model, a Bayesian inversion technique is implemented. The advantage of such an approach is to obtain robust probability density functions of interior structure parameters governed by uncertainties on the seismic data arrival times. 1-D seismic velocities are parameterized using C1-Bézier curves, which allow the exploration of both smoothly varying models and first-order discontinuities. The parameters of the inversion include the seismic velocities of P and S waves as a function of depth, the thickness of the crust under each Apollo station and impact epicentre. The forward problem consists in a ray tracing method enabling both the relocation of the natural impact epicenters, and the computation of time corrections associated to the surface topography and the crustal thickness variations under the stations and impact sites. The results show geology-related differences between the different sites, which are due to contrasts in megaregolith thickness and to shallow subsurface composition and structure. Some of the finer structural elements might be difficult to constrain and might fall within the uncertainties of the dataset. However, we use the more precise LROC-located epicentral locations for the lunar modules and Saturn-IV upper stage artificial impacts, reducing some of the uncertainties observed in past studies. In the framework of the NASA InSight/SEIS mission to Mars, the method developed in

  20. Thicknesses of Mare Basalts from Gravity and Topograhy

    Science.gov (United States)

    GONG, S.; Wieczorek, M.; Nimmo, F.; Kiefer, W.; Head, J.; Smith, D.; Zuber, M.

    2015-10-01

    Mare basalts are derived from partial melting of the lunar interior and are mostly located on the near side of the Moon [1, 2]. Their iron-rich composition gives rise to their dark color, but also causes their density to be substantially higher than normal crustal rocks. The total volume of mare basalts can provide crucial information about the Moon's thermal evolution and volcanic activity. Unfortunately, the thicknesses of the mare are only poorly constrained. Here we use gravity data from NASA's GRAIL mission to investigate the thickness of mare basalts.

  1. Thickness of tropical ice and photosynthesis on a snowball Earth

    Science.gov (United States)

    McKay, C. P.

    2000-01-01

    On a completely ice-covered "snowball" Earth the thickness of ice in the tropical regions would be limited by the sunlight penetrating into the ice cover and by the latent heat flux generated by freezing at the ice bottom--the freezing rate would balance the sublimation rate from the top of the ice cover. Heat transfer models of the perennially ice-covered Antarctic dry valley lakes applied to the snowball Earth indicate that the tropical ice cover would have a thickness of 10 m or less with a corresponding transmissivity of > 0.1%. This light level is adequate for photosynthesis and could explain the survival of the eukaryotic algae.

  2. Spacer Thickness-Dependent Electron Transport Performance of Titanium Dioxide Thick Film for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Reda E. El-Shater

    2015-01-01

    Full Text Available A titanium dioxide (P25 film was deposited by cast coating as conductive photoelectrode and subsequently immersed in dye solution (N719 to fabricate the photoanode of dye-sensitized solar cells (DSSCs. A plastic spacer was used as a separation and sealant layer between the photoanode and the counter electrode. The effect of the thickness of this spacer on the transfer of electrons in the liquid electrolyte of the DSSCs was studied by means of both IV curves and electrochemical impedance. Using a spacer thickness range of 20 μm to 50 μm, efficiency ranges from 3.73% to 7.22%. The highest efficiency of 7.22% was obtained with an optimal spacer thickness of 40 μm.

  3. Technical Note: Cortical thickness and density estimation from clinical CT using a prior thickness-density relationship

    Energy Technology Data Exchange (ETDEWEB)

    Humbert, Ludovic, E-mail: ludohumberto@gmail.com [Galgo Medical, Barcelona 08036 (Spain); Hazrati Marangalou, Javad; Rietbergen, Bert van [Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven 5600 MB (Netherlands); Río Barquero, Luis Miguel del [CETIR Centre Medic, Barcelona 08029 (Spain); Lenthe, G. Harry van [Biomechanics Section, KU Leuven–University of Leuven, Leuven 3001 (Belgium)

    2016-04-15

    Purpose: Cortical thickness and density are critical components in determining the strength of bony structures. Computed tomography (CT) is one possible modality for analyzing the cortex in 3D. In this paper, a model-based approach for measuring the cortical bone thickness and density from clinical CT images is proposed. Methods: Density variations across the cortex were modeled as a function of the cortical thickness and density, location of the cortex, density of surrounding tissues, and imaging blur. High resolution micro-CT data of cadaver proximal femurs were analyzed to determine a relationship between cortical thickness and density. This thickness-density relationship was used as prior information to be incorporated in the model to obtain accurate measurements of cortical thickness and density from clinical CT volumes. The method was validated using micro-CT scans of 23 cadaver proximal femurs. Simulated clinical CT images with different voxel sizes were generated from the micro-CT data. Cortical thickness and density were estimated from the simulated images using the proposed method and compared with measurements obtained using the micro-CT images to evaluate the effect of voxel size on the accuracy of the method. Then, 19 of the 23 specimens were imaged using a clinical CT scanner. Cortical thickness and density were estimated from the clinical CT images using the proposed method and compared with the micro-CT measurements. Finally, a case-control study including 20 patients with osteoporosis and 20 age-matched controls with normal bone density was performed to evaluate the proposed method in a clinical context. Results: Cortical thickness (density) estimation errors were 0.07 ± 0.19 mm (−18 ± 92 mg/cm{sup 3}) using the simulated clinical CT volumes with the smallest voxel size (0.33 × 0.33 × 0.5 mm{sup 3}), and 0.10 ± 0.24 mm (−10 ± 115 mg/cm{sup 3}) using the volumes with the largest voxel size (1.0 × 1.0 × 3.0 mm{sup 3}). A trend for the

  4. Light transmittance of zirconia as a function of thickness and microhardness of resin cements under different thicknesses of zirconia

    Science.gov (United States)

    Egilmez, Ferhan; Ergun, Gulfem; Kaya, Bekir M.

    2013-01-01

    Objective: The objective of this study was to compare microhardness of resin cements under different thicknesses of zirconia and the light transmittance of zirconia as a function of thickness. Study design: A total of 126 disc-shaped specimens (2 mm in height and 5 mm in diameter) were prepared from dual-cured resin cements (RelyX Unicem, Panavia F and Clearfil SA cement). Photoactivation was performed by using quartz tungsten halogen and light emitting diode light curing units under different thicknesses of zirconia. Then the specimens (n=7/per group) were stored in dry conditions in total dark at 37°C for 24 h. The Vicker’s hardness test was performed on the resin cement layer with a microhardness tester. Statistical significance was determined using multifactorial analysis of variance (ANOVA) (alpha=.05). Light transmittance of different thicknesses of zirconia (0.3, 0.5 and 0.8 mm) was measured using a hand-held radiometer (Demetron, Kerr). Data were analyzed using one-way ANOVA test (alpha=.05). Results: ANOVA revealed that resin cement and light curing unit had significant effects on microhardness (p zirconia thickness resulted in lower transmittance. There was no correlation between the amount of light transmitted and microhardness of dual-cured resin cements (r = 0.073, p = 0.295). Conclusion: Although different zirconia thicknesses might result in insufficient light transmission, dual-cured resin cements under zirconia restorations could have adequate microhardness. Key words:Zirconia, microhardness, light transmittance, resin cement. PMID:23385497

  5. Comparison of anthropometric and training characteristics between recreational male marathoners and 24-hour ultramarathoners

    Directory of Open Access Journals (Sweden)

    Rüst CA

    2012-10-01

    Full Text Available Christoph Alexander Rüst,1 Beat Knechtle,1,2 Patrizia Knechtle,2 Thomas Rosemann11Institute of General Practice and for Health Services Research, University of Zurich, Zurich, 2Gesundheitszentrum St Gallen, St Gallen, SwitzerlandBackground: Of the anthropometry and training variables used to predict race performance in a 24-hour ultrarun, the personal best marathon time is the strongest predictor in recreational male 24-hour ultramarathoners. This finding raises the question of whether similarities exist between male recreational 24-hour ultramarathoners and male recreational marathoners.Methods: The association between age, anthropometric variables (ie, body mass, body height, body mass index, percent body fat, skeletal muscle mass, limb circumference, and skinfold thickness at the pectoral, mid axillary, triceps, subscapular, abdominal, suprailiac, front thigh, and medial calf sites, previous experience and training characteristics (ie, volume, speed, and personal best time, and race time for 79 male recreational 24-hour ultramarathoners and 126 male recreational marathoners was investigated using bivariate and multivariate analysis.Results: The 24-hour ultramarathoners were older (P < 0.05, had a lower circumference at both the upper arm (P < 0.05 and thigh (P < 0.01, and a lower skinfold thickness at the pectoral, axillary, and suprailiac sites (P < 0.05 compared with the marathoners. During training, the 24-hour ultramarathoners were running for more hours per week (P < 0.001 and completed more kilometers (P < 0.001, but were running slower (P < 0.01 compared with the marathoners. In the 24-hour ultramarathoners, neither anthropometric nor training variables were associated with kilometers completed in the race (P > 0.05. In the marathoners, percent body fat (P < 0.001 and running speed during training (P < 0.0001 were related to marathon race times.Conclusion: In summary, differences in anthropometric and training predictor variables do

  6. Energy spectra of He + ions penetrating thick biological targets

    Science.gov (United States)

    Xia, Yueyuan; Tan, Chunyu; Mu, Yuguang; Wang, Ruijin; Zhang, Jianhua; Liu, Xiangdong; Liu, Jitian; Yu, Zhengliang

    1999-05-01

    Energy spectra of 500 keV-1MeV He + ion penetrating 50 μ m- 100 μ m thick seed coat of maize, fruit peel of grape and of tomato, are measured. The results indicate that these thick biological targets, as seen by the penetrating ions, are inhomogeneous, and there are open paths, along which the incident ions can penetrate the targets easily. While most of the incident ions are stopped in the targets, some of the penetrating ions only lose a small fraction of their initial incident energy. The penetration energy spectra show a pure electronic stopping feature. Transmission electron microscope (TEM) micrographs taken from these samples with thickness of 30 μ m indicate that 150 keV electron beam from the TEM can penetrate the thick samples to give very good images with clear contrast. The electronic structures of β-1,4 glucosan molecular chains, which is deemed as the most important constituent of the cell walls of seed coats and peels of fruits, are calculated to show the possible open-path directions which exist in biological samples.

  7. Modes of vibration on sqaure fiberglass epoxy composite thick plate

    Science.gov (United States)

    Williams, J. H., Jr.; Marques, E. R. C.; Lee, S. S.

    1986-01-01

    The frequencies and nodal patterns of a square thick plate of unidirectional fiberglass epoxy composite are measured experimentally. The constituent material is transversely isotropic. The plate is transversely excited at the center of the upper face, its resonant frequencies in the frequency range of 3 kHz to 21.73 kHz are detected and the measured nodal patterns are sketched.

  8. Studying uniform thickness II: Transversely nonsimple iterated torus knots

    DEFF Research Database (Denmark)

    LaFountain, Douglas

    2011-01-01

    We prove that an iterated torus knot type in the standard contact 3-sphere fails the uniform thickness property (UTP) if and only if it is formed from repeated positive cablings, which is precisely when an iterated torus knot supports the standard contact structure. This is the first complete UTP...

  9. Upper mantle viscosity and lithospheric thickness under Iceland

    NARCIS (Netherlands)

    Barnhoorn, A.; Wal, W. van der; Drury, M.R.

    2011-01-01

    Deglaciation during the Holocene on Iceland caused uplift due to glacial isostatic adjustment. Relatively low estimates for the upper mantle viscosity and lithospheric thickness result in rapid uplift responses to the deglaciation cycles on Iceland. The relatively high temperatures of the upper

  10. Reconstruction of Optical Thickness from Hoffman Modulation Contrast Images

    DEFF Research Database (Denmark)

    Olsen, Niels Holm; Sporring, Jon; Nielsen, Mads

    2003-01-01

    Hoffman microscopy imaging systems are part of numerous fertility clinics world-wide. We discuss the physics of the Hoffman imaging system from optical thickness to image intensity, implement a simple, yet fast, reconstruction algorithm using Fast Fourier Transformation and discuss the usability...

  11. Adaptive Through-Thickness Integration Strategy for Shell Elements

    NARCIS (Netherlands)

    Burchitz, I.A.; Meinders, Vincent T.; Huetink, Han

    2007-01-01

    Reliable numerical prediction of springback in sheet metal forming is essential for the automotive industry. There are numerous factors that influence the accuracy of springback prediction by using the finite element method. One of the reasons is the through-thickness numerical integration of shell

  12. Adaptive through-thickness integration for accurate springback prediction

    NARCIS (Netherlands)

    Burchitz, I.A.; Meinders, Vincent T.

    2007-01-01

    Accurate numerical prediction of springback in sheet metal forming is essential for the automotive industry. Numerous factors influence the accuracy of prediction of this complex phenomenon by using the finite element method. One of them is the numerical integration through the thickness of shell

  13. Adaptive Through-Thickness Integration Strategy for Shell Elements

    Science.gov (United States)

    Burchitz, I. A.; Meinders, T.; Huétink, J.

    2007-05-01

    Reliable numerical prediction of springback in sheet metal forming is essential for the automotive industry. There are numerous factors that influence the accuracy of springback prediction by using the finite element method. One of the reasons is the through-thickness numerical integration of shell elements. It is known that even for simple problems the traditional integration schemes may require up to 50 integration points to achieve a high accuracy of springback analysis. An adaptive through-thickness integration strategy can be a good alternative. The strategy defines abscissas and weights depending on the integrand's properties and, thus, can adapt itself to improve the accuracy of integration. A concept of the adaptive through-thickness integration strategy for shell elements is presented. It is tested using a simple problem of bending of a beam under tension. Results show that for a similar set of material and process parameters the adaptive Simpson's rule with 7 integration points performs better than the traditional trapezoidal rule with 50 points. The adaptive through-thickness integration strategy for shell elements can improve the accuracy of springback prediction at minimal costs.

  14. Relationship between placental thickness and growth parameters in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-01-19

    Jan 19, 2009 ... weight (Hebbar, 2003). These growth parameters are adversely affected by insufficient nutrients reaching the foetus through the placenta. In these foetuses the placental is often thin. A placental thickness of less than. 2.5 cm is usually associated with intrauterine growth retardation (IUGR) (Kunlmann and ...

  15. Economical Fabrication of Thick-Section Ceramic Matrix Composites

    Science.gov (United States)

    Babcock, Jason; Ramachandran, Gautham; Williams, Brian; Benander, Robert

    2010-01-01

    A method was developed for producing thick-section [>2 in. (approx.5 cm)], continuous fiber-reinforced ceramic matrix composites (CMCs). Ultramet-modified fiber interface coating and melt infiltration processing, developed previously for thin-section components, were used for the fabrication of CMCs that were an order of magnitude greater in thickness [up to 2.5 in. (approx.6.4 cm)]. Melt processing first involves infiltration of a fiber preform with the desired interface coating, and then with carbon to partially densify the preform. A molten refractory metal is then infiltrated and reacts with the excess carbon to form the carbide matrix without damaging the fiber reinforcement. Infiltration occurs from the inside out as the molten metal fills virtually all the available void space. Densification to fabrication, and testing in two complementary efforts. In a project for the Army, involving SiC/SiC blisk development, nominally 0.8 in. thick x 8 in. diameter (approx. 2 cm thick x 20 cm diameter) components were successfully infiltrated. Blisk hubs were machined using diamond-embedded cutting tools and successfully spin-tested. Good ply uniformity and extremely low residual porosity (matrix composites fabricated via CVI or PIP. The pyrolytic carbon/zirconium nitride interface coating optimized in this work for use on carbon fibers was incorporated in the SiC/SiC composites and yielded a >41 ksi (approx. 283 MPa) flexural strength.

  16. Anatomical Variation in the Wall Thickness of Wood Fibres of ...

    African Journals Online (AJOL)

    The wall thickness of wood fibres of rubber (Hevea brasiliensis) grown and tapped for latex in south eastern Nigeria were investigated to determine anatomical variation. The rubber trees which were overmature for tapping and keeping were sampled in hierarchical order of plantations, bud classes, trees, discs, cardinal ...

  17. Normative ultrasound values of renal parenchymal thickness among ...

    African Journals Online (AJOL)

    Background: Reduction in renal length was found to be an insufficient independent indicator of chronic renal disease. Objective: To determine the ultrasound normative values of renal parenchymal thickness (RPT) among adults and correlate them with age and somatometric parameters. Methods: This was a prospective ...

  18. Thick Galactic Cosmic Radiation Shielding Using Atmospheric Data

    Science.gov (United States)

    Youngquist, Robert C.; Nurge, Mark A.; Starr, Stanley O.; Koontz, Steven L.

    2013-01-01

    NASA is concerned with protecting astronauts from the effects of galactic cosmic radiation and has expended substantial effort in the development of computer models to predict the shielding obtained from various materials. However, these models were only developed for shields up to about 120 g!cm2 in thickness and have predicted that shields of this thickness are insufficient to provide adequate protection for extended deep space flights. Consequently, effort is underway to extend the range of these models to thicker shields and experimental data is required to help confirm the resulting code. In this paper empirically obtained effective dose measurements from aircraft flights in the atmosphere are used to obtain the radiation shielding function of the earth's atmosphere, a very thick shield. Obtaining this result required solving an inverse problem and the method for solving it is presented. The results are shown to be in agreement with current code in the ranges where they overlap. These results are then checked and used to predict the radiation dosage under thick shields such as planetary regolith and the atmosphere of Venus.

  19. Relationship between placental thickness and growth parameters in ...

    African Journals Online (AJOL)

    To investigate the relationship between placental thickness and foetal growth parameters in normal singleton Nigerian foetuses. Six hundred and sixty-six pregnant Nigerian women were studied by ultrasound in a cross sectional prospective study at the Federal Medical Centre, Makurdi, Nigeria. The pregnancies were in ...

  20. Microvascular Imaging of Thick Placenta with Fetal Growth Restriction.

    Science.gov (United States)

    Hata, Toshiyuki; Kanenishi, Kenji; Yamamoto, Kenta; AboEllail, Mohamed Ahmed Mostafa; Mashima, Masato; Mori, Nobuhiro

    2017-08-18

    Seven normal pregnancies at 11-34 weeks and three cases of a thick placenta with fetal growth restriction (FGR) at 19, 31, and 33 weeks were studied to assess placental vascularity using two-dimensional (2D)/three-dimensional (3D)-SMI (Aplio 800 or i900, Toshiba Medical Systems, Tokyo, Japan). This article is protected by copyright. All rights reserved.

  1. Transitional behaviour of thickness effects in shipbuilding materials (MS plate)

    Science.gov (United States)

    Mahmud, S. M. Ikhtiar; Razib, Amirul Hasan; Rahman, Md. Rabab Raiyatur

    2017-12-01

    Majority of the crack propagation in ships and offshore structures are caused due to fatigue. Previously, it was known that fatigue strength of notched specimen is dependent on size, but recently it came to light that fatigue strength of some welded joints depends on the thickness. Much investigation is done on the fatigue growth of welded joints. Fatigue often results in fracture accidents, which starts from the sites of structural discontinuities because of the reason that they may induce local stress concentrations. Structural discontinuities include notches, holes, sharp corners, and weld defects. Weld defects include undercut, porosity, lack of fusion, slag inclusion, incomplete weld root penetration, and misalignments. In order to investigate the effects of plate thickness on fatigue strength, semi-elliptical side notches (U and V shaped) in plates are studied in the present research. First consider a simple problem of crack emanating from notches in plates where the solution of stress intensity factor is given by an empirical formula so that the thickness effect on fatigue strength can easily be investigated for a variety of geometrical parameters. The present study aims to investigate the transitional behaviour of thickness effect in plates on fatigue strength. In order to calculate the stress, finite element analysis is carried by using ANSYS.

  2. Effect of thickness of bonded composite resin on compressive strength

    NARCIS (Netherlands)

    Hamburger, J.T.; Opdam, N.J.; Bronkhorst, E.M.; Roeters, J.; Huysmans, M.C.

    2014-01-01

    OBJECTIVE: The aim of this study was to investigate the compressive strength of composites with different physical properties bonded as a restoration to dentin in layers of varying thicknesses. METHODS: Four types of direct composite materials: a midway-filled (Tetric EvoCeram); a compact-filled

  3. Impact of oxide thickness on gate capacitance–Modelling and ...

    Indian Academy of Sciences (India)

    In this paper, we have developed a mathematical model to predict the behaviour of gate capacitance and threshold voltage with nanoscale variation of oxide thickness in AlInN/GaN and AlGaN/GaN metal oxide semiconductor high electron mobility transistor (MOSHEMT). The results obtained from the model are compared ...

  4. Normative ultrasound values of renal parenchymal thickness among ...

    African Journals Online (AJOL)

    Excretory urography7, computed tomography8, and ultrasound9 have been used for the development of normative standards of RPT in children. Both excretory urography and CT techniques use ionizing radiation in contrast to ultrasound which can be performed beside and is readily available. Renal parenchymal thickness.

  5. MEMS Accelerometer with Screen Printed Piezoelectric Thick Film

    DEFF Research Database (Denmark)

    Hindrichsen, Christian Carstensen; Lau-Moeller, R.; Bove, T.

    2006-01-01

    A bulk-micromachined piezoelectric MEMS accelerometer with screen printed piezoelectric Pb(ZrxTil )O3(PZT) thick film (TF) as the sensing material has been fabricated and characterized. The accelerometer has a four beam structure with a central seismic mass (3600x3600x500 pm3) and a total chip size...

  6. Heritability of carotid intima-media thickness : A twin study

    NARCIS (Netherlands)

    Zhao, Jinying; Cheema, Faiz A.; Bremner, J. Douglas; Goldberg, Jack; Su, Shaoyong; Snieder, Harold; Maisano, Carisa; Jones, Linda; Javed, Farhan; Murrah, Nancy; Le, Ngoc-Anh; Vaccarino, Viola

    Objective: To estimate the heritability of carotid intima-media thickness (IMT), a surrogate marker for atherosclerosis, independent of traditional coronary risk factors. Methods and results: We performed a classical twin study of carotid IMT using 98 middle-aged male twin pairs, 58 monozygotic (MZ)

  7. Is 'Education' a Thick Epistemic Concept? | Siegel | Philosophical ...

    African Journals Online (AJOL)

    and that, insofar, education is indeed rightly thought of as an epistemic concept. In laying out education's epistemological dimensions, I hope to clarify the degree to which it makes sense to regard the concept as 'thick'. I also discuss the relationship between philosophy of education and virtue epistemology and the sense in ...

  8. Giant moving vortex mass in thick magnetic nanodots.

    Science.gov (United States)

    Guslienko, K Y; Kakazei, G N; Ding, J; Liu, X M; Adeyeye, A O

    2015-09-10

    Magnetic vortex is one of the simplest topologically non-trivial textures in condensed matter physics. It is the ground state of submicron magnetic elements (dots) of different shapes: cylindrical, square etc. So far, the vast majority of the vortex dynamics studies were focused on thin dots with thickness 5-50 nm and only uniform across the thickness vortex excitation modes were observed. Here we explore the fundamental vortex mode in relatively thick (50-100 nm) dots using broadband ferromagnetic resonance and show that dimensionality increase leads to qualitatively new excitation spectra. We demonstrate that the fundamental mode frequency cannot be explained without introducing a giant vortex mass, which is a result of the vortex distortion due to interaction with spin waves. The vortex mass depends on the system geometry and is non-local because of important role of the dipolar interaction. The mass is rather small for thin dots. However, its importance increases drastically with the dot thickness increasing.

  9. High-velocity impact loading of thick GFRP blocks

    Science.gov (United States)

    Ernst, H.-J.; Merkel, Th.; Wolf, Th.; Hoog, K.

    2003-09-01

    In previous depth of penetration experiments with tungsten long rod projectiles was found that the ballistic resistance of a relatively thick-up to the penetrator length-glass fibre reinforced plastic block grows with increasing penetration depth. This penetration behaviour significantly differs from that of other inert armour materials. Until now, no significant difference between unconfined and totally confined GFRP configurations bas been found. Newest experiments with up to semi-infinite thick GFRP blocks show a change in the penetration process: For thicknesses significantly higher than the penetrator length the protective power may saturate. During the late penetration phase the shortening and deceleration of the projectile induce a change of penetration mechanism from erosion to rigid body penetration. Additionally, the projectile may break into several individually tumbling parts. Reflected tension waves and, probably, pyrolysis effects may cause increasing precursory damage. These effects together are likely to explain the reduction of the ballistic resistance increase during the late penetration phase. Based on these experimental results the published working hypothesis on the governing mechanism of the GFRP penetration behaviour had to be completed. A new approach based on a hyperbolic tangent function seems to satisfactorily describe the observed thickness dependent phenomena.

  10. Color Dependence on Thickness in Topaz Crystal from Brazil

    Directory of Open Access Journals (Sweden)

    Waldemar Bonventi Jr

    2012-01-01

    Full Text Available It is well known that crystals of topaz from the Eastern Brazilian Pegmatite Province may turn blue by the irradiation with 60Co gamma rays followed by heat treatment. Also, it is known that the sensation of color changes with the thickness of these crystals. The dependence of the color, given by 1931 CIE chromaticity coordinates, with the thickness of the crystal was analyzed. The absorbance used in the calculation of these coordinates was given by the sum of Gaussian lines. The parameters of these lines were determined through the decomposition of the optical absorption spectra in the ultraviolet and visible regions. The decomposition revealed several lines, whose assignment was made considering studies in spodumene and beryl crystals and highly accurate quantum mechanical calculations. The transmittance becomes very narrow with increasing thickness, and the CIE chromaticity coordinates converge to the borderline of the CIE Chromaticity Diagram at the wavelength of maximum transmittance. Furthermore, the purity of color increases with increasing thickness, and the dominant wavelength reaches the wavelength of maximum transmittance.

  11. Orbital eccentricity as a probe of thick disc formation scenarios

    NARCIS (Netherlands)

    Sales, Laura V.; Helmi, Amina; Abadi, Mario G.; Brook, Chris B.; Gomez, Facundo A.; Roskar, Rok; Debattista, Victor P.; House, Elisa; Steinmetz, Matthias; Villalobos, Alvaro

    2009-01-01

    We study the orbital properties of stars in four (published) simulations of thick discs formed by (i) accretion from disrupted satellites, (ii) heating of a pre-existing thin disc by a minor merger, (iii) radial migration and (iv) gas-rich mergers. We find that the distribution of orbital

  12. Thickness of residual wetting film in liquid-liquid displacement.

    Science.gov (United States)

    Beresnev, Igor; Gaul, William; Vigil, R Dennis

    2011-08-01

    Core-annular flow is common in nature, representing, for example, how streams of oil, surrounded by water, move in petroleum reservoirs. Oil, typically a nonwetting fluid, tends to occupy the middle (core) part of a channel, while water forms a surrounding wall-wetting film. What is the thickness of the wetting film? A classic theory has been in existence for nearly 50 years offering a solution, although in a controversial manner, for moving gas bubbles. On the other hand, an acceptable, experimentally verified theory for a body of one liquid flowing in another has not been available. Here we develop a hydrodynamic, testable theory providing an explicit relationship between the thickness of the wetting film and fluid properties for a blob of one fluid moving in another, with neither phase being gas. In its relationship to the capillary number Ca, the thickness of the film is predicted to be proportional to Ca2 at lower Ca and to level off at a constant value of ∼20% the channel radius at higher Ca. The thickness of the film is deduced to be approximately unaffected by the viscosity ratio of the fluids. We have conducted our own laboratory experiments and compiled experimental data from other studies, all of which are mutually consistent and confirm the salient features of the theory. At the same time, the classic law, originally deduced for films surrounding moving gas bubbles but often believed to hold for liquids as well, fails to explain the observations.

  13. Topsoil thickness and harvest management influence switchgrass production and profitability

    Science.gov (United States)

    Switchgrass (Panicum virgatum L.) is an attractive dual use forage and/or biomass crop option for eroded or marginal soils where corn (Zea mays L.) grain production often is not profitable. Topsoil thickness, especially above soils with a claypan, relates to crop productivity and nutrient removal an...

  14. Thickness of the electron atmosphere in large nuclear systems

    Science.gov (United States)

    Pacheco, A. F.; Sañudo, J.

    1986-03-01

    Using the relativistic Thomas-Fermi model and the virial theorem it is found that the thickness of the electron skin outside a large nuclear system is given by S⋍6.73 n-1/3, n being the electron density inside the nucleus. On leave from Departamento de Fisica Teorica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza, Spain.

  15. Thickness effect on properties of titanium film deposited by dc ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 36; Issue 5. Thickness effect on properties of titanium film deposited by d.c. magnetron sputtering and electron beam evaporation techniques. Nishat Arshi Junqing Lu Chan Gyu Lee Jae Hong Yoon Bon Heun Koo Faheem Ahmed. Volume 36 Issue 5 October 2013 pp ...

  16. Investigation of torsional vibrations in thick walled hollow poroelastic ...

    Indian Academy of Sciences (India)

    Abstract. This paper deals with the study of torsional vibrations of thick walled hollow poroelastic cylinder using Biot's extension theory. Considering the boundaries to be stress free, the frequency equation is obtained in the presence of dissipation which is transcendental and complex valued in nature. In the special case of ...

  17. Three-dimensional free vibration analysis of thick laminated circular ...

    African Journals Online (AJOL)

    In this communication, a numerical analysis regarding free vibration of thick laminated circular plates, having free, clamped as well as simply-supported boundary conditions at outer edges of plates is presented. The employment of finite element is made in this communication. The finite element methodology operates on ...

  18. Investigation of torsional vibrations in thick walled hollow poroelastic ...

    Indian Academy of Sciences (India)

    This paper deals with the study of torsional vibrations of thick walled hollow poroelastic cylinder using Biot's extension theory. Considering the boundaries to be stress free, the frequency equation is obtained in the presence of dissipation which is transcendental and complex valued in nature. In the special case of ...

  19. 3-D mapping with ellipsometrically determined physical thickness ...

    Indian Academy of Sciences (India)

    Unknown

    3-D mapping with ellipsometrically determined physical thickness/refractive index of spin coated sol–gel silica layer. S DAS, P PAL, S ROY, S CHAKRABOARTY† and P K BISWAS*. Sol–Gel Division, †Computer Section, Central Glass and Ceramic Research Institute, Kolkata 700 032, India. Abstract. Precursor sol for ...

  20. 3-D mapping with ellipsometrically determined physical thickness ...

    Indian Academy of Sciences (India)

    About 10 × 10 mm surface area of the silica layer was chosen for evaluation of thickness and refractive index values at different points (121 nos.) with 1 mm gap between two points. Those data were utilized in the Autolisp programme for 3-D mapping. Radial distribution of the evaluated values was also displayed.

  1. Shearing Nanometer-Thick Confined Hydrocarbon Films: Friction and Adhesion

    DEFF Research Database (Denmark)

    Sivebæk, I. M.; Persson, B. N. J.

    2016-01-01

    We present molecular dynamics (MD) friction and adhesion calculations for nanometer-thick confined hydrocarbon films with molecular lengths 20, 100 and 1400 carbon atoms. We study the dependency of the frictional shear stress on the confining pressure and sliding speed. We present results...

  2. Localization of abelian gauge fields on thick branes

    Energy Technology Data Exchange (ETDEWEB)

    Vaquera-Araujo, Carlos A. [Universidad de Colima, Facultad de Ciencias, CUICBAS, Colima (Mexico); Corradini, Olindo [Universidad Autonoma de Chiapas, Ciudad Universitaria, Facultad de Ciencias en Fisica y Matematicas, Tuxtla Gutierrez (Mexico); Universita di Modena e Reggio Emilia, Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Modena (Italy)

    2015-02-01

    In this work, we explore a mechanism for abelian gauge field localization on thick branes based on a five-dimensional Stueckelberg-like action. A normalizable zero mode is found through the identification of a suitable coupling function between the brane and the gauge field. The same mechanism is studied for the localization of the abelian Kalb-Ramond field. (orig.)

  3. Higher-Order Thickness Expansions for Cylindrical Shells

    Science.gov (United States)

    1991-09-01

    Engblom, John J. and 0. 0. Ochoa. "Finite Element Formulation Including Inter - laminar Stress Calculations," Computers & Structures, 23: No. 2, 241-249... Teoria Plyt Sredniej Grubbosci (Technical Theory of Plates with Moderate Thickness)," Rozprawy Inzynierskie (English Translation, Pol- ska Akademia Nauk

  4. Ice thickness, volume and subglacial topography of Urumqi Glacier ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 123; Issue 3. Ice thickness, volume and subglacial topography of Urumqi Glacier No. 1, Tianshan mountains, central Asia, by ground penetrating radar survey. Puyu Wang Zhongqin Li Shuang Jin Ping Zhou Hongbing Yao Wenbin Wang. Volume 123 Issue 3 April ...

  5. Optimisation of Plate Thickness Using Finite Difference Method ...

    African Journals Online (AJOL)

    A finite difference numerical method of solving biharmonic equation is presented. The biharmonic equation and plate theory are used to solve a classical engineering problem involving the optimisation of plate thickness to minimise deformations and stresses in the plate. Matlab routines were developed to solve the ...

  6. Macular volume and central foveal thickness measurements in ...

    African Journals Online (AJOL)

    Objective: To determine macular volume and central foveal thickness measurements in normal eyes of healthy Nigerian adults using Stratus optical coherence tomography. Subjects and Methods: Consenting 100 adults Nigerians with normal eyes were recruited and examined using Carl Zeiss Stratus Optical Coherence ...

  7. Phenotypic Correlations of Backfat Thickness with Meatiness Traits ...

    African Journals Online (AJOL)

    The aim of the present study was to determine the phenotypic correlations of backfat thickness with meatiness traits and intramuscular fat, cholesterol and fatty acid composition in the longissimus muscle of pigs. For this study, 60 barrows and 60 gilts (Pietrain × Duroc boars and Polish Large White crossbred sows) were ...

  8. Accommodating Thickness in Origami-Based Deployable Arrays

    Science.gov (United States)

    Zirbel, Shannon A.; Magleby, Spencer P.; Howell, Larry L.; Lang, Robert J.; Thomson, Mark W.; Sigel, Deborah A.; Walkemeyer, Phillip E.; Trease, Brian P.

    2013-01-01

    The purpose of this work is to create deployment systems with a large ratio of stowed-to-deployed diameter. Deployment from a compact form to a final flat state can be achieved through origami-inspired folding of panels. There are many models capable of this motion when folded in a material with negligible thickness; however, when the application requires the folding of thick, rigid panels, attention must be paid to the effect of material thickness not only on the final folded state, but also during the folding motion (i.e., the panels must not be required to flex to attain the final folded form). The objective is to develop new methods for deployment from a compact folded form to a large circular array (or other final form). This paper describes a mathematical model for modifying the pattern to accommodate material thickness in the context of the design, modeling, and testing of a deployable system inspired by an origami six-sided flasher model. The model is demonstrated in hardware as a 1/20th scale prototype of a deployable solar array for space applications. The resulting prototype has a ratio of stowed-to-deployed diameter of 9.2 (or 1.25 m deployed outer diameter to 0.136 m stowed outer diameter).

  9. Epicardial fat thickness in patients with rheumatoid arthritis | Fatma ...

    African Journals Online (AJOL)

    Background: Epidemiologic data indicates that rheumatoid arthritis is an independent risk factor for cardiovascular disease. Epicardial adipose tissue is a novel cardio-metabolic risk factor. Our aim was to evaluate epicardial fat thickness (EFT) using echocardiography in patients with rheumatoid arthritis compared to healthy ...

  10. SKINNY – SKIN thickness and Needles in the Young | Marran ...

    African Journals Online (AJOL)

    Inappropriate insulin injection technique, inadvertent intramuscular (IM) injections, needle phobia and insulin omission negatively affect glucose control. Objectives. To document skin and skin plus subcutaneous skin thickness using high resolution ultrasound (US) in a group of children and adolescents with type 1 diabetes.

  11. Genetic control of wood density and bark thickness, and their ...

    African Journals Online (AJOL)

    Tree diameter under and over bark at breast height (dbh), wood density and bark thickness were assessed on samples from control-pollinated families of Eucalyptus grandis, E. urophylla, E. grandis × E. urophylla and E. urophylla × E. grandis. The material was planted in field trials in the coastal Zululand region of South ...

  12. Basic program relates tube wall thickness and pressure

    Energy Technology Data Exchange (ETDEWEB)

    Ganapathy, V.

    1985-11-01

    A computer program, written in BASIC, which calculates safe tube pressures and necessary wall thickness is discussed. Two examples of this process are given. Computer input lists and results are presented. The program is compatible with IBM PC and similar units.

  13. Optimization of laser hole drilling process on thick gold spherical ...

    Indian Academy of Sciences (India)

    Abstract. Hohlraums of high-Z materials are used as soft X-ray sources to study indi- rect drive fusion, equation of state of materials etc. Here, we describe a method to develop spherical gold hohlraums of large wall thickness (~70–80 µm) on which laser entrance and diagnostics holes are drilled using a 10 Hz Nd:YLF laser.

  14. Through Thickness Ultrasonic Testing and Its Use in Characterising ...

    African Journals Online (AJOL)

    The stiffness coefficients of different types of limestone were determined using the through thickness ultrasonic test and measurements of size and weight, and the results obtained verified using aluminium specimens of known mechanical properties. The values of density and stiffness coefficients obtained for the various ...

  15. Ultrasound Evaluation of Intima-Media Thickness of Carotid Arteries ...

    African Journals Online (AJOL)

    Background: Ultrasound measured Carotid Intima-Media Thickness (CIMT) is a simple and inexpensive tool for assessing the cumulative effects of hypertension on the carotid arterial walls. It is also an independent predictor of future myocardial infarctionand stroke risk. Objectives: This study compared ultrasound measured ...

  16. Macular volume and central foveal thickness measurements in ...

    African Journals Online (AJOL)

    Time Domain OCT is more accurate and has faster acquisition time; this machine is not available in our institution. Normal macular volume and central foveal thickness measurements in Nigerian adults is presented and is comparable to that of Indian and Chinese populations, but lower than reported in Caucasians.

  17. Degloved foot sole successfully reconstructed with split thickness skin grafts

    NARCIS (Netherlands)

    Janssens, Loes; Holtslag, Herman R.; Schellekens, Pascal P A; Leenen, Luke P H

    2015-01-01

    Introduction The current opinion is that split thickness skin grafts are not suitable to reconstruct a degloved foot sole. The tissue is too fragile to carry full bodyweight; and therefore, stress lesions frequently occur. The treatment of choice is the reuse of the avulsed skin whenever possible,

  18. Computer vision based nacre thickness measurement of Tahitian pearls

    Science.gov (United States)

    Loesdau, Martin; Chabrier, Sébastien; Gabillon, Alban

    2017-03-01

    The Tahitian Pearl is the most valuable export product of French Polynesia contributing with over 61 million Euros to more than 50% of the total export income. To maintain its excellent reputation on the international market, an obligatory quality control for every pearl deemed for exportation has been established by the local government. One of the controlled quality parameters is the pearls nacre thickness. The evaluation is currently done manually by experts that are visually analyzing X-ray images of the pearls. In this article, a computer vision based approach to automate this procedure is presented. Even though computer vision based approaches for pearl nacre thickness measurement exist in the literature, the very specific features of the Tahitian pearl, namely the large shape variety and the occurrence of cavities, have so far not been considered. The presented work closes the. Our method consists of segmenting the pearl from X-ray images with a model-based approach, segmenting the pearls nucleus with an own developed heuristic circle detection and segmenting possible cavities with region growing. Out of the obtained boundaries, the 2-dimensional nacre thickness profile can be calculated. A certainty measurement to consider imaging and segmentation imprecisions is included in the procedure. The proposed algorithms are tested on 298 manually evaluated Tahitian pearls, showing that it is generally possible to automatically evaluate the nacre thickness of Tahitian pearls with computer vision. Furthermore the results show that the automatic measurement is more precise and faster than the manual one.

  19. Three-dimensional free vibration analysis of thick laminated circular ...

    African Journals Online (AJOL)

    Three-dimensional free vibration analysis of thick laminated circular plates. ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like more information about how to print, save, and work with PDFs, ...

  20. The thickness of the HI gas layer in spiral galaxies

    NARCIS (Netherlands)

    Sicking, Floris Jan

    1997-01-01

    In the present study, in two inclined spiral galaxies, NGC 3198 and NGC 2403, the HI random velocity dispersion and layer thickness will be measured simultaneously. This will be done from the HI velocity dispersion field (the distribution on the sky of the observed HI line of sight velocity

  1. Prognosis of Full-Thickness Skin Defects in Premature Infants

    Directory of Open Access Journals (Sweden)

    Hyung Suk Moon

    2012-09-01

    Full Text Available BackgroundIn the extremities of premature infants, the skin and subcutaneous tissue are very pliable due to immaturity and have a greater degree of skin laxity and mobility. Thus, we can expect wounds to heal rapidly by wound contraction. This study investigates wound healing of full-thickness defects in premature infant extremities.MethodsThe study consisted of 13 premature infants who had a total of 14 cases of full-thickness skin defects of the extremities due to extravasation after total parenteral nutrition. The wound was managed with intensive moist dressings with antibiotic and anti-inflammatory agents. After wound closure, moisturization and mild compression were performed.ResultsMost of the full-thickness defects in the premature infants were closed by wound contraction without granulation tissue formation on the wound bed. The defects resulted in 3 pinpoint scars, 9 linear scars, and 2 round hypertrophic scars. The wounds with less granulation tissue were healed by contraction and resulted in linear scars parallel to the relaxed skin tension line. The wounds with more granulation tissue resulted in round scars. There was mild contracture without functional abnormality in 3 cases with a defect over two thirds of the longitudinal length of the dorsum of the hand or foot. The patients' parents were satisfied with the outcomes in 12 of 14 cases.ConclusionsFull-thickness skin defects in premature infants typically heal by wound contraction with minimal granulation tissue and scar formation probably due to excellent skin mobility.

  2. Simulation of depth of penetration during ballistic impact on thick ...

    Indian Academy of Sciences (India)

    Simulation of depth of penetration during ballistic impact on thick targets using a one-dimensional discrete element model. Rajesh P Nair C Lakshmana Rao. Volume 37 Issue 2 April 2012 ... Rajesh P Nair1 C Lakshmana Rao1. Applied Mechanics Department, Indian Institute of Technology Madras, Chennai 600 036, India ...

  3. Residual Strains in Thick Thermoplastic Composites : An Experimental Approach

    NARCIS (Netherlands)

    Parlevliet, P.P.

    2010-01-01

    Thermoplastic composites are currently investigated for application in windmill turbine blades for their recyclability. A suitable manufacturing technology for these thick structures is liquid resin infusion followed by in-situ polymerisation of Anionic Polyamide-6 (APA-6). During manufacturing of

  4. Changes of macular thickness in HIV positive patients using OCT

    Directory of Open Access Journals (Sweden)

    Shang Li

    2014-10-01

    Full Text Available AIM: To assess the changes of macular thickness of acquire immunodeficiency syndrome(AIDSpatients. METHODS: The study based on the data analysis of 38 human immunodeficiency virus(HIVpositive patients(64 eyes. According to CD4 count and whether cytomegalovirus retinitis(CMVRhappened, the patients were divided into 3 groups. Group A included 16 patients(32 eyes, in which CD4 count was 50cells/μL and CMVR did not happen. Group C included 12 patients(12 eyes, in which CD4 count was RESULTS: The mean foveal thicknesses in groups A, B, C and D were 254.03±15.63μm, 263.11±17.12μm, 304.50±50.62μm and 257.64±8.54μm in order. Compared with foveal thickness in each group, there were significant differences in general(F=12.933, P=0.000. The mean foveal thickness in groups CMVR increased, which was of significant difference(P=0.000, compared with other groups.CONCLUSION: CMVR can impair the structure and function of macular, which then seriously affects the visual function of patients. It's helpful to understand the progress and prognosis of CMVR disease by observing macular structure with OCT in early time.

  5. Thickness dependent crystallographic transition in Fe/Ni multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Haeggstroem, Lennart [Department of Physics and Materials Science and Department of Materials Chemistry, Uppsala University, Box 530, 751 21 Uppsala (Sweden); Soroka, Inna [Department of Materials Chemistry, Uppsala University, Box 530, 751 21 Uppsala (Sweden); Kamali, Saeed, E-mail: lennart.haggstrom@fysik.uu.s [Department of Applied Science, University of California, Davis, Cal. 95616 (United States)

    2010-03-01

    The crystallographic transition between bcc- and fcc-structures has been studied in Fe/Ni multilayers with Moessbauer spectroscopy and X-ray diffraction. Layered structures have been confirmed and the structures depends both on individual layer thickness and the ratio of the constituents. Two sets of samples are made: the Fe layer thickness kept constant to 12 monolayer (ML) and 24ML, while the Ni layer thicknesses varied from 3 to 12ML. When the Ni layer is thin, the Fe/Ni multilayers have the bcc phase. When the thickness of Ni layer reaches 6ML and larger, a gradual transition to the fcc phase occurs. Moessbauer spectroscopy studies confirm the existence of a magnetic Fe bcc phase with in-plane magnetization in all samples, two magnetic fcc phases with fields of 28 T and 10 T and small amounts of nonmagnetic fcc phases in the thicker films. The observed behaviour can be attributed to the existence of two types of interfaces which are not necessary overlapping each other: An elemental interface between Fe and Ni and a structural interface between fcc and bcc phases.

  6. Screen printed thick film based pMUT arrays

    DEFF Research Database (Denmark)

    Hedegaard, Tobias; Pedersen, T; Thomsen, Erik Vilain

    2008-01-01

    This article reports on the fabrication and characterization of lambda-pitched piezoelectric micromachined ultrasound transducer (pMUT) arrays fabricated using a unique process combining conventional silicon technology and low cost screen printing of thick film PZT. The pMUTs are designed as 8...

  7. Global model for the lithospheric strength and effective elastic thickness

    NARCIS (Netherlands)

    Tesauro, M.; Kaban, M.K.; Cloetingh, S.A.P.L.

    2013-01-01

    Global distribution of the strength and effective elastic thickness (Te) of the lithosphere are estimated using physical parameters from recent crustal and lithospheric models. For the Te estimation we apply a new approach, which provides a possibility to take into account variations of Young

  8. Effects of Temperature Levels and Concrete Cover Thickness on ...

    African Journals Online (AJOL)

    With the knowledge of the temperature of the fire, thickness of concrete cover, residual strength of concrete and tensile strength of embedded reinforcement after fire exposure, we can predict the residual carrying capacity of the beams after fire. The experimental procedure involves some specimens of reinforcing steel bars ...

  9. Novel Genetic Variants for Cartilage Thickness and Hip Osteoarthritis

    NARCIS (Netherlands)

    M.C. Castaño Betancourt (Martha); D.S. Evans (Daniel); Y.F.M. Ramos (Yolande); Boer, C.G. (Cindy G.); S. Metrustry (Sarah); Liu, Y. (Youfang); W. den Hollander (Wouter); J. Van Rooij (Jeroen); Kraus, V.B. (Virginia B.); Yau, M.S. (Michelle S.); B.D. Mitchell (Braxton); Muir, K. (Kenneth); A. Hofman (Albert); M. Doherty (Michael); S. Doherty (Sally); W. Zhang (Weiya); R. Kraaij (Robert); F. Rivadeneira Ramirez (Fernando); Barrett-Connor, E. (Elizabeth); R.A. MacIewicz (Rose); N.K. Arden (Nigel); R.G.H.H. Nelissen (Rob); M. Kloppenburg (Margreet); Jordan, J.M. (Joanne M.); M.C. Nevitt (Michael); E. Slagboom (Eline); D. Hart (Deborah); F.P.J.G. Lafeber (Floris); U. Styrkarsdottir (Unnur); E. Zeggini (Eleftheria); E. Evangelou (Evangelos); T.D. Spector (Timothy); A.G. Uitterlinden (André); N.E. Lane; I. Meulenbelt (Ingrid); A.M. Valdes (Ana Maria); J.B.J. van Meurs (Joyce)

    2016-01-01

    textabstractOsteoarthritis is one of the most frequent and disabling diseases of the elderly. Only few genetic variants have been identified for osteoarthritis, which is partly due to large phenotype heterogeneity. To reduce heterogeneity, we here examined cartilage thickness, one of the structural

  10. Critical Layer Thickness in Exponentially Graded Heteroepitaxial Layers

    Science.gov (United States)

    Sidoti, D.; Xhurxhi, S.; Kujofsa, T.; Cheruku, S.; Reed, J.; Bertoli, B.; Rago, P. B.; Suarez, E. N.; Jain, F. C.; Ayers, J. E.

    2010-08-01

    Exponentially graded semiconductor layers are of interest for use as buffers in heteroepitaxial devices because of their tapered dislocation density and strain profiles. Here we have calculated the critical layer thickness for the onset of lattice relaxation in exponentially graded In x Ga1- x As/GaAs (001) heteroepitaxial layers. Upwardly convex grading with x = x_{infty } left( {1 - e^{ - γ /y} } right) was considered, where y is the distance from the GaAs interface, γ is a grading length constant, and x ∞ is the limiting mole fraction of In. For these structures the critical layer thickness was determined by an energy-minimization approach and also by consideration of force balance on grown-in dislocations. The force balance calculations underestimate the critical layer thickness unless one accounts for the fact that the first misfit dislocations are introduced at a finite distance above the interface. The critical layer thickness determined by energy minimization, or by a detailed force balance model, is approximately h_{{c}} ≈ 0.243μ {m}left( {γ /1μ {m}} right)^{0.5} left( {x_{infty } /0.1} right)^{ -0.54} . Although these results were developed for exponentially graded In x Ga1- x As/GaAs (001), they may be generalized to other material systems for application to the design of exponentially graded buffer layers in metamorphic device structures such as modulation-doped field-effect transistors and light-emitting diodes.

  11. The effect of thickness measurement on numerical arterial models.

    Science.gov (United States)

    de Gelidi, Serena; Tozzi, Gianluca; Bucchi, Andrea

    2017-07-01

    Several optical-based techniques for measuring the sample thickness (ST) of soft tissues have been proposed in the literature to overcome the limits of hand-operated procedures. However, ST measurement still remains arbitrary. The stress calculated during an experimental procedure, usually based on a constant thickness value for all samples, cannot be considered representative of the actual stress experienced by the tissue. Therefore, a new optical methodology to measure ST is proposed and compared to four different thickness estimations. A simplified aortic geometry, under physiologic pulsatile conditions, is used to assess the impact of ST measurement on stress predictions. An additional computational model investigates the effect of such thickness values on critical pressure levels that may instigate aneurysm formation in a homogeneous or artificially modified geometry. Comparing the results obtained for the application of a pulsatile load, wall stress values associated to minimum ST are at least 24kPa inferior to maximum ST. Critical pressure values appear to be inversely proportional to ST estimation: simulations, associated to maximum ST, predict aneurysm formation for pressure levels at least 7kPa inferior to minimum ST outcomes. Finally, the role of the strain-energy function used to fit the experimental data is demonstrated to be fundamental for predictions of aneurysm formation. Copyright © 2017. Published by Elsevier B.V.

  12. Effect of Thickness Stress in Stretch-Bending

    NARCIS (Netherlands)

    van den Boogaard, Antonius H.; Emmens, W.C.; Huetink, Han; Barlat, F; Moon, Y.H.; Lee, M.G.

    2010-01-01

    In any situation where a strip is pulled over a curved tool, locally a contact stress acts on the strip in thickness direction. This contact stress changes the stress state in the material, which will influence the deformation. One effect is that the yield stress in the plane of the strip is

  13. High-Redshift Compton Thick AGN with EXIST

    Science.gov (United States)

    Treister, Ezequiel; Urry, C.; Coppi, P.; Virani, S.

    2009-01-01

    It has been suspected for many years that a large number of heavily obscured, Compton Thick, Active Galactic Nuclei (AGN) should exist at all redshifts, but the exact number of them is still highly uncertain. Recent all-sky surveys with INTEGRAL and Swift are starting to constrain the number of Compton Thick AGN in the local Universe, zEXIST observations. We expect to find a total of 120 Compton Thick AGN at 0.5Thick AGN can be larger by 5x, thus changing significantly our view of the cosmic accretion history. E.T. gratefully acknowledges the support provided by NASA through Chandra Postdoctoral Fellowship Award Number PF8-90055 issued by the Chandra X-ray Observatory Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of NASA under contract NAS8-03060.

  14. A sensitive magnetic field sensor using BPSCCO thick film

    Indian Academy of Sciences (India)

    A highly sensitive magnetic sensor operating at liquid nitrogen temperature and based on BPSCCO screen-printed thick film, is reported. The sensor resistance for an applied magnetic field of 100 × 10–4T(100 gauss) exhibits an increase by 360% of its value in zero field at 77.4 K. The performance of the sensor in presence ...

  15. Thickness and Clapeyron slope of the post-perovskite boundary

    Energy Technology Data Exchange (ETDEWEB)

    Catalli, K.; Shim, S.-H.; Prakapenka, V.; (MIT); (UC)

    2009-12-10

    The thicknesses and Clapeyron slopes of mantle phase boundaries strongly influence the seismic detectability of the boundaries and convection in the mantle. The unusually large positive Clapeyron slope found for the boundary between perovskite (Pv) and post-perovskite (pPv) (the 'pPv boundary') would destabilize high-temperature anomalies in the lowermost mantle, in disagreement with the seismic observations. Here we report the thickness of the pPv boundary in (Mg{sub 0.91}Fe{sub 0.09}{sup 2+})SiO{sub 3} and (Mg{sub 0.9}Fe{sub 0.1}{sup 3+})(Al{sub 0.1}Si{sub 0.9})O{sub 3} as determined in a laser-heated diamond-anvil cell under in situ high-pressure (up to 145 GPa), high-temperature (up to 3,000 K) conditions. The measured Clapeyron slope is consistent with the D'' discontinuity. In both systems, however, the pPv boundary thickness increases to 400-600 {+-} 100 km, which is substantially greater than the thickness of the D'' discontinuity (<30 km). Although the Fe{sup 2+} buffering effect of ferropericlase could decrease the pPv boundary thickness, the boundary may remain thick in a pyrolitic composition because of the effects of Al and the rapid temperature increase in the D'' layer. The pPv boundary would be particularly thick in regions with an elevated Al content and/or a low Mg/Si ratio, reducing the effects of the large positive Clapeyron slope on the buoyancy of thermal anomalies and stabilizing compositional heterogeneities in the lowermost mantle. If the pPv transition is the source of the D'' discontinuity, regions with sharp discontinuities may require distinct compositions, such as a higher Mg/Si ratio or a lower Al content.

  16. Enamel thickness after preparation of tooth for porcelain laminate.

    Science.gov (United States)

    Pahlevan, Ayoub; Mirzaee, Mansoreh; Yassine, Esmaeil; Ranjbar Omrany, Ladan; Hasani Tabatabaee, Masumeh; Kermanshah, Hamid; Arami, Sakineh; Abbasi, Mehdy

    2014-07-01

    In this investigation the thickness of enamel in the gingival, middle, and incisal thirds of the labial surface of the anterior teeth were measured regarding preparation of the teeth for porcelain laminate veneers. Part one, 20 extracted intact human maxillary central and lateral incisors ten of each were selected. The teeth were imbedded in autopolimerize acrylic resin. Cross section was preformed through the midline of the incisal, middle and cervical one-third of the labial surface of the teeth. The samples were observed under reflected stereomicroscope and the thickness of enamel was recorded. Part II, the effect of different types of preparation on dentin exposure was evaluated. Thirty maxillary central incisor teeth were randomly divided into two groups: A: Knife-edge preparation. B: Chamfer preparation. All samples were embedded in autopolimerize acrylic resin using a silicon mold. The samples were cut through the midline of the teeth. The surface of the samples were polished and enamel and dentin were observed under the stereomicroscope. Data were analyzed by ANOVA-one way test. The results of this study showed that the least enamel thickness in the central incisor was 345 and in lateral incisor is 235 μ this thickness is related to the one-third labial cervical area. Maximum thickness in maxillary central and lateral incisors in the one-third labial incisal surface was 1260 μ and 1220μ, respectively. In the second part of the study, the tendency of dentinal exposure was shown with the chamfer preparation, but no dentinal exposure was found in the knife-edge preparation. The differences between groups were significant (ppreparation. The knife edge preparation is preferable in gingival area.

  17. Crown dimensions and proximal enamel thickness of mandibular second bicuspids

    Directory of Open Access Journals (Sweden)

    Sérgio Augusto Fernandes

    2011-08-01

    Full Text Available To achieve proper recontouring of anterior and posterior teeth, to obtain optimal morphology during enamel stripping, it is important to be aware of dental anatomy. This study aimed at evaluating crown dimensions and proximal enamel thickness in a sample of 40 extracted sound, human, mandibular, second bicuspids (20 right and 20 left. Mesiodistal, cervico-occlusal and buccolingual crown dimensions were measured using a digital caliper, accurate to 0.01 mm. Teeth were embedded in acrylic resin and cut along their long axes through the proximal surfaces to obtain 0.7 mm-thick central sections. Enamel thickness on the cut sections was measured using a perfilometer. Comparative analyses were carried out using the Student's-t test (α= 5%. The mean mesiodistal crown widths for right and left teeth were 7.79 mm (± 0.47 and 7.70 mm (± 0.51, respectively. Mean cervico-occlusal heights ranged from 8.31 mm (± 0.75 on the right to 8.38 mm (± 0.85 on the left teeth. The mean values for the buccolingual dimension were 8.67 mm (± 0.70 on the right and 8.65 mm (± 0.54 on the left teeth. The mean enamel thickness on the mesial surfaces ranged from 1.35 mm (± 0.22 to 1.40 mm (± 0.17, on the left and right sides, respectively. On the distal surfaces, the corresponding values were 1.44 mm (± 0.21 and 1.46 mm (± 0.12. No significant differences were found between measurements for right and left teeth. However, enamel thickness was significantly greater on the distal surfaces, compared with the mesial surfaces.

  18. Thickness and marking quality of different occlusal contact registration strips

    Directory of Open Access Journals (Sweden)

    Maria Fernanda de Souza Mauá Serapião TOLEDO

    2014-12-01

    Full Text Available Objectives Evaluate the thickness and the marking quality of different occlusal contact registration strips (OCRS and a possible correlation between them. Material and Methods The following OCRS were selected: Accufilm II, BK20, BK21, BK22, BK23, BK28, and BK31. The thickness was measured in three points of the OCRS with an electronic measuring device (TESA, and the mean was calculated. To produce the marks on the strips, composite resin specimens were adapted to a universal testing machine (Versat 2000 with 40 kgf load cell at a speed of 1.0 mm/min. The mark images were photographed with a stereoscopic microscope (Stemi SV11 and processed and analyzed by the 550-Leica Qwin® analyzer. Results Values (μm found in the 1st and 2nd thickness measurements were: Accufilm II - 16.4 and 14.2; BK20 - 10.0 and 8.1; BK21 - 9.5 and 8.0; BK22 - 9.7 and 8.7; BK23 - 9.8 and 7.9; BK28 - 12.8 and 10.0; and BK31 - 8.4 and 8.0, respectively. The mean (mm2 values found in the mark areas were: Accufilm II - 0.078; BK20 - 0.035; BK21 - 0.045; BK22 - 0.012; BK23 - 0.022; BK28 - 0.024; and BK31 - 0.024. The results were submitted to the Kruskal-Wallis (p<0.05 and Pearson’s correlation tests. Conclusions Only in the 2nd measurement, the OCRS thickness observed was similar to the value indicated by the manufacturers; the Accufilm II and the BK28 strips showed the better marks; and no correlation was found between the thickness and the marking area.

  19. Thickness and fit of mouthguards according to heating methods.

    Science.gov (United States)

    Mizuhashi, Fumi; Koide, Kaoru; Takahashi, Mutsumi

    2014-02-01

    The purpose of this study was to examine the difference in the thickness and fit of mouthguards made by four different heating methods of the mouthguard sheet material. A Sports Mouthguard(®) of 3.8-mm thickness was used in this study. Four heating methods were performed. In one method, the sheet was heated only one side. In the other methods, one side of the sheet was heated first until the center of the sheet was displaced by 0.5 cm, 1.0 cm, and 1.5 cm from the baseline, and then turned upside down and heated. The sheets were adapted using a vacuum former when the heated sheets hung 1.5 cm from the baseline. We measured the thickness and fit of the mouthguard at the areas of the central incisor and first molar. The difference in thickness at the central incisor and first molar regions was analyzed by two-way anova. The difference in fit with different heating methods was analyzed by one-way anova. The results showed that the thickness of the mouthguard differed in the central incisor and first molar areas (P heating methods. The fit of the mouthguard at the central incisor and first molar areas was significantly different among the heating methods (P heated surface of the sheet contacted the surface of the working model. This finding may help to fabricate accurate mouthguards. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Correlação entre o índice de massa corporal e a prega cutânea tricipital em crianças da cidade de Paulínia, São Paulo, SP Body mass index and triceps skinfold correlation in children from Paulínia city, São Paulo, SP

    Directory of Open Access Journals (Sweden)

    Mariana Porto Zambon

    2003-06-01

    Full Text Available O índice de massa corporal (IMC tem sido indicado como método de escolha para o diagnóstico da obesidade em adultos e crianças. OBJETIVO: Estudar a correlação existente entre o IMC e a prega cutânea tricipital (PCT. MÉTODOS: Foram avaliadas 4.236 crianças de 3,1 a 10,9 anos, 48,3% do sexo masculino e 51,6% feminino, de quatro estudos realizados em Paulínia, SP, Brasil. Mediu-se o peso e a estatura, com os quais calculou-se o IMC. A PCT foi medida com paquímetro Holtain. Os dados foram transformados em escores Z e comparados à curva norte-americana (Frisancho, 1993. A população foi dividida em grupos de acordo com os escores Z do IMC: grupo A escore Z 1. Realizou-se uma análise de regressão linear múltipla (método stepwise. Os dados foram processados no SPSS. RESULTADOS: O grupo A apresentou menor variabilidade na PCT (média 7,8; DP = 2,3 quando comparado aos demais (B: média 10,1; DP=4 e C: média 17,8; DP=4,4. Na análise da regressão linear, considerando todos os casos, a PCT apresentou R²=0,478. Nos grupos B e C a PCT teve R²=0,364 e 0,368, respectivamente enquanto no grupo A foi apenas 0,032. CONCLUSÃO: A correlação entre o IMC e a PCT é elevada no grupo de crianças com risco de obesidade (grupo C, o que justifica a substituição do uso da PCT pelo IMC em estudos populacionais de obesidade em escolares brasileiros.Body mass index (BMI has been considered a criterion to define and analyse obesity in adults and children. BACKGROUND: the purpose of this study was to evaluate the correlation between BMI and triceps skinfold (TSF. METHODS: there were studied 4,236 children (3.1-10.9y; 48.3%M:51.6%F, from four studies made in Paulínia, SP-Brazil. Height, weight and TSF (Holtain caliper were measured. For each children BMI was calculated and transformed in SDS, according to North American data (Frisancho, 1993. Multiple linear regression analysis (stepwise was used for the whole population and in three groups according

  1. Anthropometry of children with cerebral palsy at the Lagos University Teaching Hospital

    Directory of Open Access Journals (Sweden)

    Titilayo Olubunmi Adekoje

    2016-01-01

    Full Text Available Background: Cerebral palsy (CP is one the most common causes of disability among children in developing countries and is often associated with poor growth. The assessment of growth and nutrition of children is an important aspect of health monitoring and is one of the determinants of child survival. Aim: To assess the nutritional status of children with CP as seen in Lagos University Teaching Hospital (LUTH. Subjects and Methods: A prospective case-control study was conducted on children with CP attending the weekly pediatric neurology clinic of the LUTH between April 2005 and March 2006. Controls were apparently healthy children being followed up at the children′s out-patient clinic of LUTH for acute illness that had resolved. Anthropometric measurements of weight, length/height, mid-upper arm circumference, and skinfold thickness were taken according to the protocols recommended by the International Society of the Advancement of Kinanthropometry. Statistical Analysis: EPI-INFO (version 6.04 was used for analysis. Chi-square test was used to determine associations. Student′s t-test was used to compare means of patients and matched controls. Probability P < 0.05 were taken as statistically significant. Results: The controls had higher weight than the patients with mean weight (standard deviation of 13.7 (4.8 kg, and 12.0 (4.5 kg, respectively (P = 0.01. There were also statistically significant differences in the subscapular and biceps skinfold measurements between the patient and control groups (P = 0.00004 and 0.000008, respectively. Twenty-four (25.8% and 5 (5.4% of the patients had moderate and severe undernutrition compared to 6 (6.1% and none, respectively, in the control group (P = 0.00005. Conclusion: Children with CP had significantly lower mean anthropometric parameters and were more malnourished compared with the control group of children matched for age, sex, and social class.

  2. Using receiver operating characteristic curve analysis in detecting excess adiposity in 9-13-year old South African children.

    Science.gov (United States)

    Goon, D T; Toriola, A L; Shaw, B S

    2012-10-01

    Little is known concerning the applicability of receiver operating characteristic (ROC) curve analysis in detecting excess adiposity in preadolescent South African children. Therefore, the purpose of this study was to evaluate the sensitivity and specificity of body mass index (BMI) and skinfold thickness: BMI (subcutaneous to overall fat) in detecting excess adiposity in preadolescent urban South African school children. This was a cross-sectional survey of 1136 randomly selected children (548 boys and 588 girls) aged 9-13 years old in urban (Pretoria Central) South Africa. Body mass, stature, skinfolds (subscapular, triceps, supraspinale and biceps) and waist circumference were measured. Receiver operating characteristic curve analysis was used to assess the sensitivity and specificity of BMI, and log10 SF4:BMI to detect excess adiposity. Excess adiposity was defined as levels of log10 SF4 greater than the internally derived 85th percentile (log10 SF4 > 85th percentile). Compared to log10 SF4:BMI, BMI had a high specificity (0.88; 95% CI 0.84, 0.90). The log10 SF4:BMI identified excess adiposity with a sensitivity and specificity of 0.62 (95% CI 0.60, 0.67) and 0.68 (95% CI 0.64, 0.70), respectively. Besides, a decrease in overall misclassification with the use of log10 SF4:BMI instead of BMI at the 95th percentile (9.7% versus 27.1%) was observed. Similar to other studies, although with varying degrees, the present study confirms that log10 SF4:BMI at conventional cut-off points has a relatively high sensitivity and specificity in detecting excess adiposity, and therefore could be used to identify the excess adiposity in South African children. As such, defining obesity based on population-specific percentiles rather than using cut-off points derived from other geographical settings with contrasting levels of socio-economic development becomes imperative.

  3. Prevalence of overweight and obesity among Costa Rican elementary school children

    Directory of Open Access Journals (Sweden)

    Hilda Patricia Núñez-Rivas

    2003-01-01

    Full Text Available OBJECTIVE: Given that excessive body weight during childhood influences the development of several chronic diseases in adulthood, this study was conducted to determine the prevalence of overweight and obesity in urban and rural Costa Rican elementary school children. METHODS: The study was carried out from July 2000 to April 2001. A total of 1718 students ages 7-12 were selected from 34 schools in the capital city of San José and in other nearby urban and rural areas. Both younger children (ones aged 7 through 9 years and older children (ones aged 10 through 12 years with a body mass index (BMI at or above the sex-specific 85th percentile were considered overweight. The younger children were classified as being obese if their triceps skinfold was greater than or equal to the 85th percentile for age and sex using the percentiles by age for children in the United States of America as normative standards. The older children were considered obese if they had a BMI at or above the sex-specific 85th percentile and both the triceps and subscapular skinfold thickness at or above the 90th percentile. RESULTS: The prevalence of overweight was 34.5%. Children aged 7-9, boys, children from urban areas, and children of a higher socioeconomic status had a higher prevalence of overweight. The prevalence of obesity was 26.2%. A higher prevalence of obesity was found among children aged 7-9, boys, children from urban areas, and children of middle socioeconomic status. CONCLUSIONS: Given the high prevalence of obesity that we found in the Costa Rican children, primary and secondary prevention measures are needed in order to reduce the proportion of deaths due to chronic nontransmissible diseases among Costa Rican adults in the coming decades.

  4. The reports of thick discs' deaths are greatly exaggerated. Thick discs are NOT artefacts caused by diffuse scattered light

    Science.gov (United States)

    Comerón, S.; Salo, H.; Knapen, J. H.

    2018-02-01

    Recent studies have made the community aware of the importance of accounting for scattered light when examining low-surface-brightness galaxy features such as thick discs. In our past studies of the thick discs of edge-on galaxies in the Spitzer Survey of Stellar Structure in Galaxies - the S4G - we modelled the point spread function as a Gaussian. In this paper we re-examine our results using a revised point spread function model that accounts for extended wings out to more than 2\\farcm5. We study the 3.6 μm images of 141 edge-on galaxies from the S4G and its early-type galaxy extension. Thus, we more than double the samples examined in our past studies. We decompose the surface-brightness profiles of the galaxies perpendicular to their mid-planes assuming that discs are made of two stellar discs in hydrostatic equilibrium. We decompose the axial surface-brightness profiles of galaxies to model the central mass concentration - described by a Sérsic function - and the disc - described by a broken exponential disc seen edge-on. Our improved treatment fully confirms the ubiquitous occurrence of thick discs. The main difference between our current fits and those presented in our previous papers is that now the scattered light from the thin disc dominates the surface brightness at levels below μ 26 mag arcsec-2. We stress that those extended thin disc tails are not physical, but pure scattered light. This change, however, does not drastically affect any of our previously presented results: 1) Thick discs are nearly ubiquitous. They are not an artefact caused by scattered light as has been suggested elsewhere. 2) Thick discs have masses comparable to those of thin discs in low-mass galaxies - with circular velocities vc< 120 km s-1 - whereas they are typically less massive than the thin discs in high-mass galaxies. 3) Thick discs and central mass concentrations seem to have formed at the same epoch from a common material reservoir. 4) Approximately 50% of the up

  5. Comparing Geophysical Methods for Determining the Thickness of Arctic Sea Ice: Is There a Correlation Between Thickness and Surface Temperature?

    Science.gov (United States)

    Robertson, R.; Bowman, T.; Eagle, J. L.; Fisher, L.; Mankowski, K.; McGrady, N.; Schrecongost, N.; Voll, H.; Zulfiqar, A.; Herman, R. B.

    2016-12-01

    Several small geophysical surveys were conducted on the Chukchi Sea ice just offshore from the Naval Arctic Research Laboratory near Barrow, Alaska, in March, 2016. The goal was to investigate a possible correlation between the surface temperature and the thickness of the sea ice, as well as to test a potential new method for more accurately determining ice thickness. Surveys were conducted using a capacitively coupled resistivity array, a custom built thermal sensor array sled, ground penetrating radar (GPR), and an ice drill. The thermal sensor array was based on an Arduino microcontroller. It used an infrared (IR) sensor to determine surface temperature, and thermistor-based sensors to determine vertical air temperatures at 6 evenly spaced heights up to a maximum of 1.5 meters. Surface temperature (IR) data show possible correlations with ice drill, resistivity, and GPR data. The vertical air sensors showed almost no variation for any survey line which we postulate is due to the constant wind during each survey. Ice drill data show ice thickness along one 200 meter line varied from 79-95 cm, with an average of 87 cm. The thickness appears to be inversely correlated to surface temperatures. Resistivity and IR data both showed abrupt changes when crossing from the shore to the sea ice along a 400 meter line. GPR and IR data showed similar changes along a separate 900 meter line, suggesting that surface temperature and subsurface composition are related. Resistivity data were obtained in two locations by using the array in an expanding dipole-dipole configuration with 2.5 meter dipoles. The depth to the ice/water boundary was calculated using a "cumulative resistivity" plot and matched the depths obtained via the ice drill to within 2%. This has initiated work to develop a microcontroller-based resistivity array specialized for thickness measurements of thin ice.

  6. Diagnostic capability of retinal thickness measures in diabetic peripheral neuropathy.

    Science.gov (United States)

    Srinivasan, Sangeetha; Pritchard, Nicola; Sampson, Geoff P; Edwards, Katie; Vagenas, Dimitrios; Russell, Anthony W; Malik, Rayaz A; Efron, Nathan

    To examine the diagnostic capability of the full retinal and inner retinal thickness measures in differentiating individuals with diabetic peripheral neuropathy (DPN) from those without neuropathy and non-diabetic controls. Individuals with (n=44) and without (n=107) diabetic neuropathy and non-diabetic control (n=42) participants underwent spectral domain optical coherence tomography (SDOCT). Retinal thickness in the central 1mm zone (including the fovea), parafovea and perifovea was assessed in addition to ganglion cell complex (GCC) global loss volume (GCC GLV) and focal loss volume (GCC FLV), and retinal nerve fiber layer (RNFL) thickness. Diabetic neuropathy was defined using a modified neuropathy disability score (NDS) recorded on a 0-10 scale, wherein, NDS ≥3 indicated neuropathy and NDS indicated neuropathy. Diagnostic performance was assessed by areas under the receiver operating characteristic curves (AUCs), 95 per cent confidence intervals (CI), sensitivities at fixed specificities, positive likelihood ratio (+LR), negative likelihood ratio (-LR) and the cut-off points for the best AUCs obtained. The AUC for GCC FLV was 0.732 (95% CI: 0.624-0.840, pneuropathy from those without neuropathy, the AUCs of retinal parameters ranged from 0.508 for the central zone to 0.690 for the inferior RNFL thickness. For distinguishing those with moderate or advanced neuropathy from those with mild or no neuropathy, the inferior RNFL thickness demonstrated the highest AUC of 0.820, (95% CI: 0.731-0.909, pdiabetic neuropathy from healthy controls, while the inferior RNFL thickness is able to differentiate those with greater degrees of neuropathy from those with mild or no neuropathy, both with an acceptable level of accuracy. Optical coherence tomography represents a non-invasive technology that aids in detection of retinal structural changes in patients with established diabetic neuropathy. Further refinement of the technique and the analytical approaches may be

  7. Longitudinal changes in cortical thickness in autism and typical development

    Science.gov (United States)

    Prigge, Molly B. D.; Nielsen, Jared A.; Froehlich, Alyson L.; Abildskov, Tracy J.; Anderson, Jeffrey S.; Fletcher, P. Thomas; Zygmunt, Kristen M.; Travers, Brittany G.; Lange, Nicholas; Alexander, Andrew L.; Bigler, Erin D.; Lainhart, Janet E.

    2014-01-01

    The natural history of brain growth in autism spectrum disorders remains unclear. Cross-sectional studies have identified regional abnormalities in brain volume and cortical thickness in autism, although substantial discrepancies have been reported. Preliminary longitudinal studies using two time points and small samples have identified specific regional differences in cortical thickness in the disorder. To clarify age-related trajectories of cortical development, we examined longitudinal changes in cortical thickness within a large mixed cross-sectional and longitudinal sample of autistic subjects and age- and gender-matched typically developing controls. Three hundred and forty-five magnetic resonance imaging scans were examined from 97 males with autism (mean age = 16.8 years; range 3–36 years) and 60 males with typical development (mean age = 18 years; range 4–39 years), with an average interscan interval of 2.6 years. FreeSurfer image analysis software was used to parcellate the cortex into 34 regions of interest per hemisphere and to calculate mean cortical thickness for each region. Longitudinal linear mixed effects models were used to further characterize these findings and identify regions with between-group differences in longitudinal age-related trajectories. Using mean age at time of first scan as a reference (15 years), differences were observed in bilateral inferior frontal gyrus, pars opercularis and pars triangularis, right caudal middle frontal and left rostral middle frontal regions, and left frontal pole. However, group differences in cortical thickness varied by developmental stage, and were influenced by IQ. Differences in age-related trajectories emerged in bilateral parietal and occipital regions (postcentral gyrus, cuneus, lingual gyrus, pericalcarine cortex), left frontal regions (pars opercularis, rostral middle frontal and frontal pole), left supramarginal gyrus, and right transverse temporal gyrus, superior parietal lobule, and

  8. Reflectance dependence of polytetrafluoroethylene on thickness for xenon scintillation light

    Energy Technology Data Exchange (ETDEWEB)

    Haefner, J.; Neff, A.; Arthurs, M.; Batista, E.; Morton, D.; Okunawo, M.; Pushkin, K.; Sander, A. [Randall Laboratory of Physics, University of Michigan, Ann Arbor, MI 48109-1040 (United States); Stephenson, S. [Randall Laboratory of Physics, University of Michigan, Ann Arbor, MI 48109-1040 (United States); University of California Davis, Department of Physics, One Shields Ave., Davis, CA 95616 (United States); Wang, Y. [Randall Laboratory of Physics, University of Michigan, Ann Arbor, MI 48109-1040 (United States); Lorenzon, W., E-mail: lorenzon@umich.edu [Randall Laboratory of Physics, University of Michigan, Ann Arbor, MI 48109-1040 (United States)

    2017-06-01

    Many rare event searches including dark matter direct detection and neutrinoless double beta decay experiments take advantage of the high VUV reflective surfaces made from polytetrafluoroethylene (PTFE) reflector materials to achieve high light collection efficiency in their detectors. As the detectors have grown in size over the past decade, there has also been an increased need for ever thinner detector walls without significant loss in reflectance to reduce dead volumes around active noble liquids, outgassing, and potential backgrounds. We report on the experimental results to measure the dependence of the reflectance on thickness of two PTFE samples at wavelengths near 178 nm. No change in reflectance was observed as the wall thickness of a cylindrically shaped PTFE vessel immersed in liquid xenon was varied between 1 mm to 9.5 mm.

  9. Preauricular full-thickness skin grafting in medial canthal reconstruction

    Directory of Open Access Journals (Sweden)

    Rafael Corredor-Osorio

    2018-02-01

    Full Text Available Basal cell carcinoma in medial canthal is a surgical challenge to oculoplastic surgeon. We report a case an 80 –year-old woman who presented with a vegetative tumor in the right inferior medial canthus that increased slowly in size over the past two years. An excisional biopsy from the tumor was suggestive of a basal cell carcinoma. A full-thickness excision of the tumor within the oncologic safety limits, was performed. A wide range of reconstruction techniques should be customized to the individual patient. In this case, the use of a preauricular full. Thickness skin graft was a favorable option, without complications, and with acceptable functional and cosmetic results. The aim of the treatment is to restore anatomy, functional and cosmetic of the patients.

  10. The aerodynamic properties of thick aerofoils suitable for internal bracing

    Science.gov (United States)

    Norton, F H

    1920-01-01

    The object of this investigation was to determine the characteristics of various types of wings having sufficient depth to entirely inclose the wing bracing, and also to provide data for the further design of such sections. This type of wing is of interest because it eliminates the resistance of the interplane bracing, a portion of the airplane that sometimes absorbs one-quarter of the total power required to fly, and because these wings may be made to give a very high maximum lift. Results of the investigation of the following subjects are given: (1) effect of changing the upper and lower camber of thick aerofoils of uniform section; (2) effect of thickening the center and thinning the tips of a thin aerofoil; (3) effect of adding a convex lower surface to a tapered section; (4) effect of changing the mean thickness with constant center and tip sections; and (5) effect of varying the chord along the span.

  11. ′Switch flap′ for full thickness upper eyelid reconstruction

    Directory of Open Access Journals (Sweden)

    Arvind Krishnamurthy

    2011-01-01

    Full Text Available Sebaceous gland carcinoma is an aggressive, uncommon, cutaneous malignancy. This tumour can arise anywhere in the body; approximately 75% of these tumours arise in the periocular region. The diagnosis and management of these malignancies often tend to get delayed because they are frequently mistaken for more common benign entities. Surgery has been and remains the primary treatment modality for sebaceous gland carcinomas. The resultant surgical defects following tumour excision generally tend to be full thickness and reconstructions of such defects pose significant challenges. These defects are conventionally reconstructed by the traditional bridging (eyelid sharing procedures, that is, the Cutler-Beard flap and its modifications. The ′Switch flap′ is an alternative eyelid sharing procedure; however, it is not very widely practiced. We recently used this procedure to reconstruct a large full-thickness upper eyelid defect with a satisfactory cosmetic and functional outcome.

  12. Thick brane in f( R) gravity with Palatini dynamics

    Science.gov (United States)

    Bazeia, D.; Losano, L.; Menezes, R.; Olmo, Gonzalo J.; Rubiera-Garcia, D.

    2015-12-01

    This work deals with modified gravity in five-dimensional space-time. We study a thick Palatini f( R) brane, that is, a braneworld scenario described by an anti-de Sitter warped geometry with a single extra dimension of infinite extent, sourced by a real scalar field under the Palatini approach, where the metric and the connection are regarded as independent degrees of freedom. We consider a first-order framework which we use to provide exact solutions for the scalar field and warp factor. We also investigate a perturbative scenario such that the Palatini approach is implemented through a Lagrangian f(R)=R+ɛ R^n, where the small parameter ɛ controls the deviation from the standard thick brane case. In both cases it is found that the warp factor tends to localize the extra dimension due to the nonlinear corrections.

  13. Evolution of thick domain walls in de Sitter universe

    CERN Document Server

    Dolgov, A D; Rudenko, A S

    2016-01-01

    We consider thick domain walls in a de Sitter universe following paper by Basu and Vilenkin. However, we are interested not only in stationary solutions found therein, but also investigate the general case of domain wall evolution with time. When the wall thickness parameter, $\\delta_0$, is smaller than $H^{-1}/\\sqrt{2}$, where $H$ is the Hubble parameter in de Sitter space-time, then the stationary solutions exist, and initial field configurations tend with time to the stationary ones. However, there are no stationary solutions for $\\delta_0 \\geq H^{-1}/\\sqrt{2}$. We have calculated numerically the rate of the wall expansion in this case and have found that the width of the wall grows exponentially fast for $\\delta_0 \\gg H^{-1}$. An explanation for the critical value $\\delta_{0c} = H^{-1}/\\sqrt{2}$ is also proposed.

  14. Imaging the inside of thick structures using cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Guardincerri, E., E-mail: elenaguardincerri@lanl.gov; Durham, J. M.; Morris, C.; Bacon, J. D.; Daughton, T. M.; Fellows, S.; Morley, D. J.; Johnson, O. R.; Plaud-Ramos, K.; Poulson, D. C.; Wang, Z. [Los Alamos National Laboratory, Los Alamos, NM, 87545 (United States)

    2016-01-15

    The authors present here a new method to image reinforcement elements inside thick structures and the results of a demonstration measurement performed on a mock-up wall built at Los Alamos National Laboratory. The method, referred to as “multiple scattering muon radiography”, relies on the use of cosmic-ray muons as probes. The work described in this article was performed to prove the viability of the technique as a means to image the interior of the dome of Florence Cathedral Santa Maria del Fiore, one of the UNESCO World Heritage sites and among the highest profile buildings in existence. Its result shows the effectiveness of the technique as a tool to radiograph thick structures and image denser object inside them.

  15. Probing the neutron skin thickness in collective modes of excitation

    Directory of Open Access Journals (Sweden)

    Paar N.

    2014-03-01

    Full Text Available Nuclear collective motion provides valuable constraint on the size of neutron-skin thickness and the properties of nuclear matter symmetry energy. By employing relativistic nuclear energy density functional (RNEDF and covariance analysis related to χ2 fitting of the model parameters, relevant observables are identified for dipole excitations, which strongly correlate with the neutron-skin thickness (rnp, symmetry energy at saturation density (J and slope of the symmetry energy (L. Using the RNEDF framework and experimental data on pygmy dipole strength (68Ni, 132Sn, 208Pb and dipole polarizability (208Pb, it is shown how the values of J, and L, and rnp are constrained. The isotopic dependence of moments associated to dipole excitations in 116–136Sn shows that the low-energy dipole strength and polarizability in neutron-rich nuclei display strong sensitivity to the symmetry energy parameter J, more pronounced than in isotopes with moderate neutron-to-proton number ratios.

  16. Engine bearing oil film thickness measurement and oil rheologh

    Energy Technology Data Exchange (ETDEWEB)

    Cryvoff, S.A.; Spearot, J.A.; Bates, T.W.

    1990-01-01

    An American Society for Testing and Materials (ASTM) Task Force was formed in 1984 to: (1) establish a series of reference oils, (2) measure the minimum bearing oil film thicknesses provided by the oils in fired engine, and (3) interpret the results in terms of oil rheological properties. Minimum oil film thickness (MOFT) measurement and analysis techniques using a capacitance method were developed. At steady-state operating conditions, laboratories evaluated a matrix of eighteen monograde and multigrade oils, blended with four widely-used viscosity index improves (VIIs). Analyses showed increasingly better correlations between MOFTs and viscosities of both single grade and multigrade oils as temperatures and shear rates used to calculate viscosities more-closely approximated in-bearing conditions.

  17. Mössbauer spectroscopy under acoustical excitation: thick target effects

    Science.gov (United States)

    Sadykov, E. K.; Yurichuk, A. A.; Vagizov, F. G.; Mubarakshin, Sh. I.; Valiullin, A. A.

    2017-11-01

    A new model of Mössbauer absorption (transmission) spectra with an adequate analysis of the possible effects of acoustic excitation in the thick targets is proposed. In particular, the dependence of the line width of acoustical satellites on the degree of phase correlation of the sound oscillations of resonant nuclei in the target is established by calculations and confirmed in experiment. Such a model is stimulated by an increase in the informativeness of the Mössbauer experiments, using thick samples in ultrasound (US) field, and by possible applications of this research technique. The test measurements of Mössbauer absorption spectra on stainless steel are carried out. The fitting of these spectra confirms the relevance of modifications of the model base of Mössbauer processes in US field.

  18. Micrometer-thickness liquid sheet jets flowing in vacuum

    Science.gov (United States)

    Galinis, Gediminas; Strucka, Jergus; Barnard, Jonathan C. T.; Braun, Avi; Smith, Roland A.; Marangos, Jon P.

    2017-08-01

    Thin liquid sheet jet flows in vacuum provide a new platform for performing experiments in the liquid phase, for example X-ray spectroscopy. Micrometer thickness, high stability, and optical flatness are the key characteristics required for successful exploitation of these targets. A novel strategy for generating sheet jets in vacuum is presented in this article. Precision nozzles were designed and fabricated using high resolution (0.2 μm) 2-photon 3D printing and generated 1.49 ± 0.04 μm thickness, stable, and <λ /20-flat jets in isopropanol under normal atmosphere and under vacuum at 5 × 10-1 mbar. The thin sheet technology also holds great promise for advancing the fields of high harmonic generation in liquids, laser acceleration of ions as well as other fields requiring precision and high repetition rate targets.

  19. Thickness vibrations of a piezoelectric plate with dissipation.

    Science.gov (United States)

    Lee, Peter C Y; Liu, Ninghui; Ballato, Arthur

    2004-01-01

    The three-dimensional (3-D) equations of linear piezoelectricity with quasi-electrostatic approximation are extended to include losses attributed to the acoustic viscosity and electrical conductivity. These equations are used to investigate effects of dissipation on the propagation of plane waves in an infinite solid and forced thickness vibrations in an infinite piezoelectric plate with general symmetry. For a harmonic plane wave propagating in an arbitrary direction in an unbounded solid, the complex eigenvalue problem is solved from which the effective elastic stiffness, viscosity, and conductivity are computed. For the forced thickness vibrations of an infinite plate, the complex coupling factor K*, input admittance Y are derived and an explicit, approximate expression for K* is obtained in terms of material properties. Effects of the viscosity and conductivity on the resonance frequency, modes, admittance, attenuation coefficient, dynamic time constant, coupling factor, and quality factor are calculated and examined for quartz and ceramic barium titanate plates.

  20. Rapid optical determination of topological insulator nanoplate thickness and oxidation

    Directory of Open Access Journals (Sweden)

    Fan Yang

    2017-01-01

    Full Text Available The stability of 2D antimony telluride (Sb2Te3 nanoplates in ambient conditions is elucidated. These materials exhibit an anisotropic oxidation mode, and CVD synthesized samples oxidize at a much faster rate than exfoliated samples investigated in previous studies. Optical measurement techniques are introduced to rapidly measure the oxidation modes and thickness of 2D materials. Auger characterization were conducted to confirm that oxygen replaces tellurium as opposed to antimony under ambient conditions. No surface morphology evolution was detected in AFM before and after exposure to air. These techniques were employed to determine the origin of the thickness dependent color change effect in Sb2Te3. It is concluded that this effect is a combination of refractive index change due to oxidation and Fresnel effects.