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Sample records for strength body composition

  1. Strength training and body composition in middle-age women.

    Science.gov (United States)

    Burrup, Rachelle; Tucker, Larry A; LE Cheminant, James D; Bailey, Bruce W

    2018-01-01

    Strength training is a sound method to improve body composition. However, the effect of age, diet, menopause, and physical activity on the relationship between strength training and body composition in women remains unknown. The purpose of this study was to examine the intricacies of the relationship between strength training and body composition in 257 middle-age women and to quantify the effect of these factors on the association. The study was cross-sectional. Five variables were used to index strength training participation. Body composition was assessed by dual-energy X-ray absorptiometry. Diet was assessed by 7-day weighed food records, and physical activity was measured objectively using accelerometers. There were 109 strength trainers in the sample. For each day per week of strength training, body fat was 1.3 percentage points lower (F=14.8, Pdevote to strength training, the lower their body fat and the higher their fat-free mass tend to be. A significant portion of the differences in body composition seems to result from lifters participating in more physical activity than non-lifters. Menopause status also contributes significantly to the relationship.

  2. Effect of Protein Intake on Strength, Body Composition and Endocrine Changes in Strength/Power Athletes

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    Kang Jie

    2006-12-01

    Full Text Available Abstract Comparison of protein intakes on strength, body composition and hormonal changes were examined in 23 experienced collegiate strength/power athletes participating in a 12-week resistance training program. Subjects were stratified into three groups depending upon their daily consumption of protein; below recommended levels (BL; 1.0 – 1.4 g·kg-1·day-1; n = 8, recommended levels (RL; 1.6 – 1.8 g·kg-1·day-1; n = 7 and above recommended levels (AL; > 2.0 g·kg-1·day-1; n = 8. Subjects were assessed for strength [one-repetition maximum (1-RM bench press and squat] and body composition. Resting blood samples were analyzed for total testosterone, cortisol, growth hormone, and insulin-like growth factor. No differences were seen in energy intake (3,171 ± 577 kcal between the groups, and the energy intake for all groups were also below the recommended levels for strength/power athletes. No significant changes were seen in body mass, lean body mass or fat mass in any group. Significant improvements in 1-RM bench press and 1-RM squat were seen in all three groups, however no differences between the groups were observed. Subjects in AL experienced a 22% and 42% greater change in Δ 1-RM squat and Δ 1-RM bench press than subjects in RL, however these differences were not significant. No significant changes were seen in any of the resting hormonal concentrations. The results of this study do not provide support for protein intakes greater than recommended levels in collegiate strength/power athletes for body composition improvements, or alterations in resting hormonal concentrations.

  3. Associations of maximal strength and muscular endurance test scores with cardiorespiratory fitness and body composition.

    Science.gov (United States)

    Vaara, Jani P; Kyröläinen, Heikki; Niemi, Jaakko; Ohrankämmen, Olli; Häkkinen, Arja; Kocay, Sheila; Häkkinen, Keijo

    2012-08-01

    The purpose of the present study was to assess the relationships between maximal strength and muscular endurance test scores additionally to previously widely studied measures of body composition and maximal aerobic capacity. 846 young men (25.5 ± 5.0 yrs) participated in the study. Maximal strength was measured using isometric bench press, leg extension and grip strength. Muscular endurance tests consisted of push-ups, sit-ups and repeated squats. An indirect graded cycle ergometer test was used to estimate maximal aerobic capacity (V(O2)max). Body composition was determined with bioelectrical impedance. Moreover, waist circumference (WC) and height were measured and body mass index (BMI) calculated. Maximal bench press was positively correlated with push-ups (r = 0.61, p strength (r = 0.34, p strength correlated positively (r = 0.36-0.44, p test scores were related to maximal aerobic capacity and body fat content, while fat free mass was associated with maximal strength test scores and thus is a major determinant for maximal strength. A contributive role of maximal strength to muscular endurance tests could be identified for the upper, but not the lower extremities. These findings suggest that push-up test is not only indicative of body fat content and maximal aerobic capacity but also maximal strength of upper body, whereas repeated squat test is mainly indicative of body fat content and maximal aerobic capacity, but not maximal strength of lower extremities.

  4. Weight, body composition and handgrip strength among pulmonary tuberculosis patients

    DEFF Research Database (Denmark)

    Praygod, George; Range, Nyagosya; Faurholt-Jepsen, Daniel

    2011-01-01

    This study aimed to estimate deficits in weight, arm fat area (AFA), arm muscle area (AMA) and handgrip strength among smear-positive pulmonary TB (PTB+) patients starting treatment. We conducted a cross-sectional study among PTB+ patients and age- and sex-matched neighborhood controls. HIV statu...

  5. Effects of high-intensity strength interval training program on body composition

    OpenAIRE

    Juránková, Michaela; Bílý, Jiří; Hrazdíra, Eduard

    2015-01-01

    The aim of this work was to examine effects of 10-week high-intensity strength interval training (HIIT) program on body composition. Seven women (31.0 ± 6.0 years old, 65.7 ± 9.8 kg body weight, 23.6 ± 2.8 kg*m−2 BMI, 18.6 ± 5.8 kg body fat, 26.0 ± 3.4 kg muscle mass) completed intervention program. We performed an analyze of body composition before and after training program. We focused especially on body fat and muscle mass. Each session consisted of short term bouts (until 30 s duration) w...

  6. Changes in body composition, diet, and strength of bodybuilders during the 12 weeks prior to competition.

    Science.gov (United States)

    Bamman, M M; Hunter, G R; Newton, L E; Roney, R K; Khaled, M A

    1993-12-01

    The purpose of this study was to monitor body composition, diet, and strength in male bodybuilders (No. 6) during the 12 weeks prior to competition. Data were collected every third week and analyzed with repeated measures ANOVA (p training volumes were found during pre-competition. Nutritional analyses showed significant reductions (p pre-competition practices were effective in reducing subcutaneous fat stores while maintaining muscle. Finally, the onset of the pre-competition phase resulted in strength loss.

  7. Effects of weightlifting vs. kettlebell training on vertical jump, strength, and body composition.

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    Otto, William H; Coburn, Jared W; Brown, Lee E; Spiering, Barry A

    2012-05-01

    Effects of weightlifting vs. kettlebell training on vertical jump, strength, and body composition. J Strength Cond Res 26(5): 1199-1202, 2012-The present study compared the effects of 6 weeks of weightlifting plus traditional heavy resistance training exercises vs. kettlebell training on strength, power, and anthropometric measures. Thirty healthy men were randomly assigned to 1 of 2 groups: (a) weightlifting (n = 13; mean ± SD: age, 22.92 ± 1.98 years; body mass, 80.57 ± 12.99 kg; height, 174.56 ± 5.80 cm) or (b) kettlebell (n = 17; mean ± SD: age, 22.76 ± 1.86 years; body mass, 78.99 ± 10.68 kg; height, 176.79 ± 5.08 cm) and trained 2 times a week for 6 weeks. A linear periodization model was used for training; at weeks 1-3 volume was 3 × 6 (kettlebell swings or high pull), 4 × 4 (accelerated swings or power clean), and 4 × 6 (goblet squats or back squats), respectively, and the volume increased during weeks 4-6 to 4 × 6, 6 × 4, and 4 × 6, respectively. Participants were assessed for height (in centimeters), body mass (in kilograms), and body composition (skinfolds). Strength was assessed by the back squat 1 repetition maximum (1RM), whereas power was assessed by the vertical jump and power clean 1RM. The results of this study indicated that short-term weightlifting and kettlebell training were effective in increasing strength and power. However, the gain in strength using weightlifting movements was greater than that during kettlebell training. Neither method of training led to significant changes in any of the anthropometric measures. In conclusion, 6 weeks of weightlifting induced significantly greater improvements in strength compared with kettlebell training. No between-group differences existed for the vertical jump or body composition.

  8. Association between fitness and changes in body composition and muscle strength.

    NARCIS (Netherlands)

    Koster, A.; Visser, M.; Simonsick, E.M.; Yu, B.; Allison, D.B.; Newman, A.B.; van Eijk, J.T.; Schwartz, A.V.; Satterfield, S.; Harris, T.B.

    2010-01-01

    Objectives: To examine the association between physical fitness, assessed according to ability and time to complete a 400-m walk, on changes in body composition and muscle strength over a 7-year period. Design: Prospective observational cohort study. Setting: Memphis, Tennessee, and Pittsburgh,

  9. Improving body composition and strength in athletes through a 4-month combined martial arts and strength training program

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    Aleksandra Stachoń

    2016-06-01

    2Zakład Sportów Indywidualnych, Akademia Wychowania Fizycznego, ul. Paderewskiego 35, Wrocław       Corresponding author: Dr Aleksandra Jadwiga Stachoń, e-mail: aleksandra.stachon@awf.wroc.pl Departament of Physical Anthropology, University School of Physical Education in Wrocław, al. I.J. Paderewskiego 35, bud. P2, 51-612 Wrocław; Poland Phone: 71 347 33 44         Key words: resistance training, body build, body composition, combat sport.   Abstract Background and aim. Body composition is one of key components of health in both general and athletic populations. In martial arts great significance is attached to the development of mesomorphy and strength, which are crucial for performing offensive and defensive actions during fights. The study proposes to introduce progressive strength training programme - arranged primarily for beginners – in order to improve body composition of non-elite male martial arts competitors. The present study aims to evaluate the changes in body massiveness, body composition and strength in 31 martial arts practitioners from academic sports clubs after a combined martial arts and strength training programme. Material and methods. The 16-week intervention was based on a targeted progressive resistance training protocol developed by Stefaniak [1995]. The anthropometric, physical and motoric measurements were performed twice at four months interval. This programme includes training three times weekly with increased number of repetitions (19-24, number of sets (1-3 and increased loads (5%. Results. After the completion of the training program, significant increase for about 1.8 kgin body mass was observed. Body massiveness (BMI increased from 23.2 ± 1.8 kg/m2 to 23.9 ± 1.8 kg/m2. The analysis using Sheldon’s somatotypes revealed an increase of mesomorphy (from 5.5 to 5.7 and decrease of ectomorphy (from 2.5 to 2.4. The level of endomorphy became stable (2.1. The maximal circumferences of flexed arm, forearm, calf and

  10. Body composition, muscle strength and hormonal status in patients with ataxia telangiectasia: a cohort study.

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    Pommerening, H; van Dullemen, S; Kieslich, M; Schubert, R; Zielen, S; Voss, S

    2015-12-09

    Ataxia-telangiectasia (A-T) is a devastating human autosomal recessive disorder that causes progressive cerebellar ataxia, immunodeficiency, premature aging, chromosomal instability and increased cancer risk. Affected patients show growth failure, poor weight gain, low body mass index (BMI), myopenia and increased fatigue during adolescence. The prevalence of alterations in body composition, muscle strength and hormonal status has not been well described in classical A-T patients. Additionally, no current guidelines are available for the assessment and management of these changes. We analyzed body composition, manual muscle strength and hormonal status in 25 A-T patients and 26 age-matched, healthy controls. Bioelectrical impedance analysis (BIA) was performed to evaluate the body composition, fat-free mass (FFM), body cell mass (BCM), extracellular matrix (ECM), phase angle (PhA), fat mass (FM) and ECM to BCM ratio. Manual muscle strength was measured using a hydraulic hand dynamometer. The BMI, FFM and PhA were significantly lower in A-T patients than in controls (BMI 16.56 ± 3.52 kg/m(2) vs. 19.86 ± 3.54 kg/m(2); Z-Score: -1.24 ± 1.29 vs. 0.05 ± 0.92, p body composition, characterized by depleted BMI, PhA and BCM; by the need to sit in a wheelchair; by altered hormone levels; and by poor muscle strength, is a major factor underlying disease progression and increased fatigue in A-T patients. ClinicalTrials.gov NCT02345200.

  11. Effects of different strength training frequencies on maximum strength, body composition and functional capacity in healthy older individuals.

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    Turpela, Mari; Häkkinen, Keijo; Haff, Guy Gregory; Walker, Simon

    2017-11-01

    There is controversy in the literature regarding the dose-response relationship of strength training in healthy older participants. The present study determined training frequency effects on maximum strength, muscle mass and functional capacity over 6months following an initial 3-month preparatory strength training period. One-hundred and six 64-75year old volunteers were randomly assigned to one of four groups; performing strength training one (EX1), two (EX2), or three (EX3) times per week and a non-training control (CON) group. Whole-body strength training was performed using 2-5 sets and 4-12 repetitions per exercise and 7-9 exercises per session. Before and after the intervention, maximum dynamic leg press (1-RM) and isometric knee extensor and plantarflexor strength, body composition and quadriceps cross-sectional area, as well as functional capacity (maximum 7.5m forward and backward walking speed, timed-up-and-go test, loaded 10-stair climb test) were measured. All experimental groups increased leg press 1-RM more than CON (EX1: 3±8%, EX2: 6±6%, EX3: 10±8%, CON: -3±6%, Ptraining frequency would induce greater benefit to maximum walking speed (i.e. functional capacity) despite a clear dose-response in dynamic 1-RM strength, at least when predominantly using machine weight-training. It appears that beneficial functional capacity improvements can be achieved through low frequency training (i.e. 1-2 times per week) in previously untrained healthy older participants. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Strength, body composition, and functional outcomes in the squat versus leg press exercises.

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    Rossi, Fabrício E; Schoenfeld, Brad J; Ocetnik, Skyler; Young, Jonathan; Vigotsky, Andrew; Contreras, Bret; Krieger, James W; Miller, Michael G; Cholewa, Jason

    2018-03-01

    The purpose of this study was to compare strength, body composition, and functional outcome measures following performance of the back squat, leg press, or a combination of the two exercises. Subjects were pair-matched based on initial strength levels and then randomly assigned to 1 of 3 groups: a squat-only group (SQ) that solely performed squats for the lower body; a leg press-only group (LP) that solely performed leg presses for the lower body, or a combined squat and leg press group (SQ-LP) that performed both squats and leg presses for the lower body. All other RT variables were held constant. The study period lasted 10 weeks with subjects performing 2 lower body workouts per week comprising 6 sets per session at loads corresponding to 8-12 RM with 90- to 120-second rest intervals. Results showed that SQ had greater transfer to maximal squat strength compared to the leg press. Effect sizes favored SQ and SQ-LP versus LP with respect to countermovement jump while greater effect sizes for dynamic balance were noted for SQ-LP and LP compared to SQ, although no statistical differences were noted between conditions. These findings suggest that both free weights and machines can improve functional outcomes, and that the extent of transfer may be specific to the given task.

  13. Body Composition, Muscular Strength and Bone Status among Undernourished Children in Malaysia

    International Nuclear Information System (INIS)

    Chong, Kar Hau; Poh, Bee Koon

    2014-01-01

    Full text: Despite significant advances in social and economic development, undernutrition remains a devastating public health problem that affects millions of children across the globe, particularly in developing nations. It is important to understand how changes in nutritional status affect physical health and function, so that undernutrition-related alterations can be identified and interpreted correctly. This paper aimed to determine the impact of undernutrition in children through the assessment of three nutrition-related indicators: body composition, muscular strength and bone status. This study is part of the Nutrition Survey of Malaysian Children, which is part of the four-country South East Asian Nutrition Surveys (SEANUTS). A total of 208 school children (102 boys, 106 girls) in the age range of 7 to 10 years were included in this analysis, of which 104 were underweight (WAZ<-2SD) and 104 were normal-weight group (-2SD≤WAZ≤+2SD), individually-matched for sex, age, and ethnicity. Anthropometric measurements included weight and height; and body composition was measured by bioelectrical impedance analysis. Muscular strength of both hands was assessed independently by hand-held dynamometer. Bone status was evaluated using a radial quantitative ultrasound system at one-third distal radius of the non-dominant hand. Anthropometric measurements and bone status were not significantly different between the sexes. Boys had significantly higher muscular strength and lean mass (p<0.05), but lower fat mass when compared to the girls (p<0.01). In both sexes, the undernourished group presented significantly lower anthropometric and body composition measurements and muscular strength than their normal-weight counterparts (p<0.001). However, no significant differences were observed for bone status between the two weight groups in boys (p = 0.09) and girls (p = 0.98). These findings imply that undernutrition can have profound negative impact on body composition as well

  14. Estimation of 1RM for knee extension based on the maximal isometric muscle strength and body composition.

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    Kanada, Yoshikiyo; Sakurai, Hiroaki; Sugiura, Yoshito; Arai, Tomoaki; Koyama, Soichiro; Tanabe, Shigeo

    2017-11-01

    [Purpose] To create a regression formula in order to estimate 1RM for knee extensors, based on the maximal isometric muscle strength measured using a hand-held dynamometer and data regarding the body composition. [Subjects and Methods] Measurement was performed in 21 healthy males in their twenties to thirties. Single regression analysis was performed, with measurement values representing 1RM and the maximal isometric muscle strength as dependent and independent variables, respectively. Furthermore, multiple regression analysis was performed, with data regarding the body composition incorporated as another independent variable, in addition to the maximal isometric muscle strength. [Results] Through single regression analysis with the maximal isometric muscle strength as an independent variable, the following regression formula was created: 1RM (kg)=0.714 + 0.783 × maximal isometric muscle strength (kgf). On multiple regression analysis, only the total muscle mass was extracted. [Conclusion] A highly accurate regression formula to estimate 1RM was created based on both the maximal isometric muscle strength and body composition. Using a hand-held dynamometer and body composition analyzer, it was possible to measure these items in a short time, and obtain clinically useful results.

  15. Estimation of 1RM for knee extension based on the maximal isometric muscle strength and body composition

    OpenAIRE

    Kanada, Yoshikiyo; Sakurai, Hiroaki; Sugiura, Yoshito; Arai, Tomoaki; Koyama, Soichiro; Tanabe, Shigeo

    2017-01-01

    [Purpose] To create a regression formula in order to estimate 1RM for knee extensors, based on the maximal isometric muscle strength measured using a hand-held dynamometer and data regarding the body composition. [Subjects and Methods] Measurement was performed in 21 healthy males in their twenties to thirties. Single regression analysis was performed, with measurement values representing 1RM and the maximal isometric muscle strength as dependent and independent variables, respectively. Furth...

  16. Effects of Strength Training Combined with Specific Plyometric exercises on body composition, vertical jump height and lower limb strength development in elite male handball players: a case study

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    Carvalho Alberto

    2014-07-01

    Full Text Available The purpose of the present study was to identify the effects of a strength training program combined with specific plyometric exercises on body composition, vertical jump (VJ height and strength development of lower limbs in elite male handball players. A 12-week program with combined strength and specific plyometric exercises was carried out for 7 weeks. Twelve elite male handball players (age: 21.6 ± 1.73 competing in the Portuguese Major League participated in the study. Besides the anthropometric measurements, several standardized jump tests were applied to assess VJ performance together with the strength development of the lower limbs in an isokinetic setting. No significant changes were found in body circumferences and diameters. Body fat content and fat mass decreased by 16.4 and 15.7% respectively, while lean body mass increased by 2.1%. Despite small significance, there was in fact an increase in squat jump (SJ, counter movement jump (CMJ and 40 consecutive jumps after the training period (6.1, 3.8 and 6.8%, respectively. After the applied protocol, peak torque increased in lower limb extension and flexion in the majority of the movements assessed at 90°s-1. Consequently, it is possible to conclude that combining general strength-training with plyometric exercises can not only increase lower limb strength and improve VJ performance but also reduce body fat content.

  17. Effects of Strength Training Combined with Specific Plyometric exercises on body composition, vertical jump height and lower limb strength development in elite male handball players: a case study.

    Science.gov (United States)

    Carvalho, Alberto; Mourão, Paulo; Abade, Eduardo

    2014-06-28

    The purpose of the present study was to identify the effects of a strength training program combined with specific plyometric exercises on body composition, vertical jump (VJ) height and strength development of lower limbs in elite male handball players. A 12-week program with combined strength and specific plyometric exercises was carried out for 7 weeks. Twelve elite male handball players (age: 21.6 ± 1.73) competing in the Portuguese Major League participated in the study. Besides the anthropometric measurements, several standardized jump tests were applied to assess VJ performance together with the strength development of the lower limbs in an isokinetic setting. No significant changes were found in body circumferences and diameters. Body fat content and fat mass decreased by 16.4 and 15.7% respectively, while lean body mass increased by 2.1%. Despite small significance, there was in fact an increase in squat jump (SJ), counter movement jump (CMJ) and 40 consecutive jumps after the training period (6.1, 3.8 and 6.8%, respectively). After the applied protocol, peak torque increased in lower limb extension and flexion in the majority of the movements assessed at 90ºs-1. Consequently, it is possible to conclude that combining general strength-training with plyometric exercises can not only increase lower limb strength and improve VJ performance but also reduce body fat content.

  18. Effects of Endurance and Endurance Strength Training on Body Composition and Physical Capacity in Women with Abdominal Obesity

    Science.gov (United States)

    Skrypnik, Damian; Bogdański, Paweł; Mądry, Edyta; Karolkiewicz, Joanna; Ratajczak, Marzena; Kryściak, Jakub; Pupek-Musialik, Danuta; Walkowiak, Jarosław

    2015-01-01

    Aims To compare the effects of endurance training with endurance strength training on the anthropometric, body composition, physical capacity, and circulatory parameters in obese women. Methods 44 women with abdominal obesity were randomized into groups A and B, and asked to perform endurance (A) and endurance strength training (B) for 3 months, 3 times/week, for 60 min. Dual-energy X-ray absorptiometry and Graded Exercise Test were performed before and after training. Results Significant decreases in body mass, BMI, total body fat, total body fat mass, and waist and hip circumference were observed after both types of intervention. Marked increases in total body lean and total body fat-free mass were documented in group B. In both groups, significant increases in peak oxygen uptake, time to exhaustion, maximal work rate, and work rate at ventilatory threshold were accompanied by noticeably decreased resting heart rate, resting systolic blood pressure, and resting and exercise diastolic blood pressure. No significant differences were noticed between groups for the investigated parameters. Conclusion Our findings demonstrate evidence for a favorable and comparable effect of 3-month endurance and endurance strength training on anthropometric parameters, body composition, physical capacity, and circulatory system function in women with abdominal obesity. PMID:25968470

  19. The impact of a 12-week resistance training program on strength, body composition, and self-concept of Hispanic adolescents.

    Science.gov (United States)

    Velez, Amelia; Golem, Devon L; Arent, Shawn M

    2010-04-01

    Current evidence suggests that a resistance training program may be physically and psychologically beneficial for adolescents. The purpose of this study was to examine the effects of a structured resistance training program on strength, body composition, and self-concept in normal and overweight Hispanic adolescents. Male and female participants (n = 28; 16.1 +/- 0.2 y; 164.5 +/- 1.4 cm; 63.3 +/- 2.5 kg; 20.0 +/- 1.7% body fat [BF]) were recruited from a predominantly Hispanic high school. Prior to the 12-week program, strength, body composition, and self-concept were assessed. Subjects were randomly assigned to a control group (CON; n = 15) or to a resistance training group (RT; n = 13) that participated in supervised strength training 3 days/week. All measures were repeated at the end of the 12-week program. RT had significantly greater strength increases for bench press (p increased %BF. RT had an increase in condition/stamina competence (p = 0.008), attractive body adequacy (p = 0.017), and global self-worth (p = 0.013) from pretest to posttest, whereas no change was observed for CON. In conclusion, resistance training resulted in significant physiological and psychological improvements in Hispanic adolescents compared to typical school-based activities. These findings indicate that resistance training can be incorporated into the activities of Hispanic adolescents to promote improved health and fitness.

  20. EFFECTS OF CREATINE, GINSENG, AND ASTRAGALUS SUPPLEMENTATION ON STRENGTH, BODY COMPOSITION, MOOD, AND BLOOD LIPIDS DURING STRENGTH-TRAINING IN OLDER ADULTS

    Directory of Open Access Journals (Sweden)

    Michael E. Rogers

    2006-03-01

    Full Text Available The effects of supplemental dietary creatine and a botanical extract consisting of ginseng and astragalus were evaluated in 44 adults aged 55-84 years participating in a 12-week strength-training program. Participants consumed creatine only (Cr, creatine plus botanical extract (CrBE, or placebo (PL, and performed bench press, lat pull down, biceps curl, leg press, knee extension, and knee flexion for 3 sets of 8-12 reps on 3 days per week for 12 weeks. The 1-repetition maximum for each exercise, body composition (full-body DEXA, blood lipids, and mood states were evaluated before and after the intervention. Training improved (p < 0.05 strength and lean mass for all groups, however greater gains were observed with Cr and CrBE compared with placebo (but no difference was found between Cr and CrBE. Only CrBE improved blood lipids and self-reported vigor, and the CrBE group lost significantly more body fat and gained more bench press strength than Cr. These results indicate that strength and lean mass gains achieved by older adults participating in a strength training program can be enhanced with creatine supplementation, and that ginseng and astragalus may provide additional health and psychological benefits. However, these herbs do not appear to have an additive effect on strength and lean mass gains during training

  1. The effect of winter sports participation on high school football players: strength, power, agility, and body composition.

    Science.gov (United States)

    Wroble, R R; Moxley, D R

    2001-02-01

    In this study, football players (N = 57) in grades 9-11 from 3 high schools chose to participate in 1 of 2 groups. Group WC (N = 39) participated in off-season strength training only. Group SP (N = 18) participated in both a winter sport (either wrestling or basketball) and an identical strength training program. All participants were tested at the close of football season (Pre) and at the end of the winter sports season (Post), a period of 4 months. Body composition (weight [W] and body fat percentage [BF]), strength (calculated 1RM [1 repetition maximum] max for barbell bench press [BP] and squat [SQ]), power (vertical jump [VJ] and seated shot put [UP]), and agility (18.3-m agility run [AG]) were measured. Both groups WC and SP increased significantly in W and BF and improved significantly in BP and VJ (p training.

  2. Effects of Different Types of Exercise on Body Composition, Muscle Strength, and IGF-1 in the Elderly with Sarcopenic Obesity.

    Science.gov (United States)

    Chen, Hung-Ting; Chung, Yu-Chun; Chen, Yu-Jen; Ho, Sung-Yen; Wu, Huey-June

    2017-04-01

    To investigate the influence of resistance training (RT), aerobic training (AT), or combination training (CT) interventions on the body composition, muscle strength performance, and insulin-like growth factor 1 (IGF-1) of patients with sarcopenic obesity. Randomized controlled trial. Community center and research center. Sixty men and women aged 65-75 with sarcopenic obesity. Participants were randomly assigned to RT, AT, CT, and control (CON) groups. After training twice a week for 8 weeks, the participants in each group ceased training for 4 weeks before being examined for the retention effects of the training interventions. The body composition, grip strength, maximum back extensor strength, maximum knee extensor muscle strength, and blood IGF-1 concentration were measured. The skeletal muscle mass (SMM), body fat mass, appendicular SMM/weight %, and visceral fat area (VFA) of the RT, AT, and CT groups were significantly superior to those of the CON group at both week 8 and week 12. Regarding muscle strength performance, the RT group exhibited greater grip strength at weeks 8 and 12 as well as higher knee extensor performance at week 8 than that of the other groups. At week 8, the serum IGF-1 concentration of the RT group was higher than the CON group, whereas the CT group was superior to the AT and CON groups. Older adults with sarcopenic obesity who engaged in the RT, AT, and CT interventions demonstrated increased muscle mass and reduced total fat mass and VFA compared with those without training. The muscle strength performance and serum IGF-1 level in trained groups, especially in the RT group, were superior to the control group. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

  3. Effects of Whole-Body Electromyostimulation versus High-Intensity Resistance Exercise on Body Composition and Strength: A Randomized Controlled Study

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    Wolfgang Kemmler

    2016-01-01

    Full Text Available High-intensity (resistance exercise (HIT and whole-body electromyostimulation (WB-EMS are both approaches to realize time-efficient favorable changes of body composition and strength. The purpose of this study was to determine the effectiveness of WB-EMS compared with the gold standard reference HIT, for improving body composition and muscle strength in middle-aged men. Forty-eight healthy untrained men, 30–50 years old, were randomly allocated to either HIT (2 sessions/week or a WB-EMS group (3 sessions/2 weeks that exercised for 16 weeks. HIT was applied as “single-set-to-failure protocol,” while WB-EMS was conducted with intermittent stimulation (6 s WB-EMS, 4 s rest; 85 Hz, 350 ms over 20 minutes. The main outcome parameters were lean body mass (LBM as determined via dual-energy X-ray absorptiometry and maximum dynamic leg-extensor strength (isokinetic leg-press. LBM changes of both groups (HIT 1.25 ± 1.44% versus WB-EMS 0.93±1.15% were significant (p=.001; however, no significant group differences were detected (p=.395. Leg-extensor strength also increased in both groups (HIT 12.7±14.7%, p=.002, versus WB-EMS 7.3±10.3%, p=.012 with no significant (p=.215 between-group difference. Corresponding changes were also determined for body fat and back-extensor strength. Conclusion. In summary, WB-EMS can be considered as a time-efficient but pricy option to HIT-resistance exercise for people aiming at the improvement of general strength and body composition.

  4. Efficacy of WBV as a modality for inducing changes in body composition, aerobic fitness, and muscular strength: a pilot study

    Directory of Open Access Journals (Sweden)

    Tapp LR

    2013-12-01

    Full Text Available Lauren R Tapp,1,3 Joseph F Signorile1,2,41Departments of Kinesiology and Sport Sciences, Coral Gables, 2Center on Aging, University of Miami Miller School of Medicine, Miami, FL, 3Department of Kinesiology, Temple University, Philadelphia, PA, 4Geriatric Research, Education, and Clinical Center, Bruce W Carter Department of Veterans Affairs Medical Center, Miami, FL, USAAbstract: The purpose of this pilot study was to evaluate the effectiveness of whole body vibration (WBV training as a modality for inducing changes in body composition, cardiovascular condition, and muscular strength in sedentary postmenopausal women. WBV training was compared with other training regimens, ie, aerobic training and circuit resistance training, commonly used to promote weight loss, cardiovascular conditioning, and muscular strength. Postmenopausal women (aged 48–60 years were randomly assigned to WBV training, circuit resistance training, or aerobic training. Participants trained three times per week for 8 weeks. The training regimens were progressive in nature, with increases in training intensity and duration occurring throughout the 8-week period. Body composition was assessed using dual-energy X-ray absorptiometry analyses. A modified Bruce treadmill protocol was used to assess aerobic capacity (VO2peak and time to peak exhaustion. Upper and lower body strengths were determined by one repetition maximum (1-RM chest and leg presses, respectively. Variables were analyzed using separate 3 (exercise mode × 2 (time repeated-measures analysis of variance with effect sizes due to the small sample size. No significant main effects or interactions were seen for any body composition variable; however, moderate to large effect sizes (η2=0.243 and η2=0.257 were detected regarding interactions for percent body fat and lean body mass favoring aerobic training and circuit resistance training. For VO2peak, no significant main effects or interactions were detected (time

  5. [Effect of high impact movements on body composition, strength and bone mineral density on women over 60 years].

    Science.gov (United States)

    Ramírez-Villada, Jhon F; León-Ariza, Henry H; Argüello-Gutiérrez, Yenny P; Porras-Ramírez, Keyla A

    2016-01-01

    Osteoporosis is characterised by loss of bone mass and deterioration of bone tissue microarchitecture that leads to fragility related to the risk of fractures. The aim of the study is to analyse the effects of a training program based on explosive movements and impact, assessed in a swimming pool, on body composition, explosive strength and bone mineral density in women over 60 years old. A total of 35 healthy physically active women (60±4.19 years) were divided into a training pool group using multi jumps (JG) and a control group (CG). JG trained for 24 weeks, 3 times a week, an hour and a half per session. Body composition testing, explosive strength, and bone mineral density were assessed before and after the program. There were differences in the explosive force (JG vs CG=P<.05 to .001) and the estimated power (JG vs CG=P<.05 to .002) between JG vs CG, with significant increases in JG. There were no significant differences in the percentage of fat and lean mass, bone mineral density lumbar and femoral between groups, although slightly significant increases in bone mineral density lumbar and femoral could be seen in JG after program implementation (JG pre-test vs JG post- test=P<.05). The training program with impact and explosive movements assessed in a pool induces gains in muscle strength and power with slight adaptations in body mass index in women over 60 years. Copyright © 2015 SEGG. Published by Elsevier Espana. All rights reserved.

  6. CHANGES IN MAXIMAL STRENGTH AND BODY COMPOSITION AFTER DIFFERENT METHODS OF DEVELOPING MUSCLE STRENGTH AND SUPPLEMENTATION WITH CREATINE, L-CARNITINE AND HMB

    Directory of Open Access Journals (Sweden)

    M Kruszewski

    2011-06-01

    Full Text Available The aim of the present study was to assess the effects of bodybuilding training combined with administration of L-carnitine, weightlifting training combined with administration of creatine, and isometric training combined with administration of β-hydroxy-β-methylbutyrate (HMB on maximal strength and body composition of athletes. The studies were conducted on groups of beginners practising bodybuilding training (n=63 and isometric training (n=69 as well as on a group of advanced powerlifters (n=50 practising weightlifting training. The obtained results indicate that the most desirable and beneficial supportive effect in strength sports was exhibited by HMB. No significant differences in body composition of subjects practising bodybuilding training were detected between those who were given L-carnitine and those who received placebo, an observation confirming controversies over the capacity of the former to reduce fat content. However, significant differences in maximal strength were demonstrated between the examined groups of athletes. Significant differences in the examined parameters were also detected within the group of advanced powerlifters practising weightlifting between those who were supplemented with creatine and those who were given placebo. Thus, the use of creatine in the development of physical capacity in advanced athletes may be advisable.

  7. Effect of floorball training on blood lipids, body composition, muscle strength, and functional capacity of elderly men

    DEFF Research Database (Denmark)

    Vorup Petersen, Jacob; Pedersen, Mogens Theisen; Melcher, Pia Grethe Sandfeld

    2017-01-01

    Floorball training consists of intense repeated exercise and may offer a motivating and social stimulating team activity in elderly individuals. However, the effect of floorball training in elderly adults on physiological adaptations important for health is not known. Thus, this study examined...... the effect of floorball training on blood lipids, muscle strength, body composition, and functional capacity of men aged 65-76 years. Thirty-nine recreational active men were randomized into a floorball group (FG; n = 22) or petanque group (PG; n = 17), in which training was performed 1 h twice a week for 12......-IR) was reduced (P performance in four different...

  8. The effects of two equal-volume training protocols upon strength, body composition and salivary hormones in male rugby union players

    Directory of Open Access Journals (Sweden)

    BT Crewther

    2016-04-01

    Full Text Available This study examined the effects of two equal-volume resistance-training protocols upon strength, body composition and salivary hormones in male rugby union players. Using a crossover design, 24 male rugby players completed a 4-week full-body (FB and split-body (SB training protocol of equal volume during the competitive season. One repetition maximum (1RM strength, body composition via skinfold measurements and salivary testosterone (T and cortisol (C concentrations were assessed pre and post training. The FB and SB protocols improved upper (7.3% and 7.4% and lower body 1RM strength (7.4% and 5.4%, whilst reducing body fat (-0.9% and -0.4% and fat mass (-5.7% and -2.1%, respectively (all p ≤ 0.021. The SB protocol elevated T (21% and C (50% concentrations with a higher T/C ratio (28% after FB training (all p ≤ 0.039. The strength changes were similar, but the body composition and hormonal results differed by protocol. Slope testing on the individual responses identified positive associations (p ≤ 0.05 between T and C concentrations and absolute 1RM strength in stronger (squat 1RM = 150.5 kg, but not weaker (squat 1RM = 117.4 kg, men. A short window of training involving FB or SB protocols can improve strength and body composition in rugby players. The similar strength gains highlight training volume as a key adaptive stimulus, although the programme structure (i.e. FB or SB did influence the body composition and hormonal outcomes. It also appears that 1RM strength is associated with individual hormonal changes and baseline strength.

  9. The effects of two equal-volume training protocols upon strength, body composition and salivary hormones in male rugby union players

    Science.gov (United States)

    Heke, TOL; Keogh, JWL

    2016-01-01

    This study examined the effects of two equal-volume resistance-training protocols upon strength, body composition and salivary hormones in male rugby union players. Using a crossover design, 24 male rugby players completed a 4-week full-body (FB) and split-body (SB) training protocol of equal volume during the competitive season. One repetition maximum (1RM) strength, body composition via skinfold measurements and salivary testosterone (T) and cortisol (C) concentrations were assessed pre and post training. The FB and SB protocols improved upper (7.3% and 7.4%) and lower body 1RM strength (7.4% and 5.4%), whilst reducing body fat (-0.9% and -0.4%) and fat mass (-5.7% and -2.1%), respectively (all p ≤ 0.021). The SB protocol elevated T (21%) and C (50%) concentrations with a higher T/C ratio (28%) after FB training (all p ≤ 0.039). The strength changes were similar, but the body composition and hormonal results differed by protocol. Slope testing on the individual responses identified positive associations (p ≤ 0.05) between T and C concentrations and absolute 1RM strength in stronger (squat 1RM = 150.5 kg), but not weaker (squat 1RM = 117.4 kg), men. A short window of training involving FB or SB protocols can improve strength and body composition in rugby players. The similar strength gains highlight training volume as a key adaptive stimulus, although the programme structure (i.e. FB or SB) did influence the body composition and hormonal outcomes. It also appears that 1RM strength is associated with individual hormonal changes and baseline strength. PMID:27274103

  10. Dietary intake habits and controlled training on body composition and strength in elite female volleyball players during the season.

    Science.gov (United States)

    Mielgo-Ayuso, Juan; Zourdos, Michael C; Calleja-González, Julio; Urdampilleta, Aritz; Ostojic, Sergej M

    2015-08-01

    The purpose of this study was to assess dietary intake of elite female volleyball players (EFVPs, n = 22) during the first 11 weeks of the competitive season. Further, we compared findings for total energy intake and specific macronutrient distribution with the established recommendations for high-intensity athletes. Subjects also engaged in periodized training and we assessed changes in body composition (BC) and strength. Twenty-two EFVPs had dietary intake (7-day dietary recall and food-frequency questionnaire), BC (body mass index (BMI), body fat percentage, fat mass, muscle mass), and 1-repetition maximum (1RM) strength (bench press, military press, back squat, power clean, clean and jerk, pull-over) assessed at baseline (T0, before preseason) and 11 weeks later (T11). Athletes consumed less total kilocalories and carbohydrates (CHO) compared with established recommendations (total kilocalories: 40.7 ± 5.2 kcal/(kg · day)(-1) vs. 50-80 kcal/(kg · day)(-1); CHO: 4.3 ± 0.6 g/(kg · day)(-1) vs. 5-8 g/(kg · day)(-1)). Further, subjects consumed greater protein (2.1 ± 0.4 g/(kg · day)(-1)) compared with recommendations (1.6-1.8 g/(kg · day)(-1)) and greater fat (36.1 ± 4.6% of total kilocalories) than recommendations (20%-35% of total kilocalories). There were improvements (p 0.05) in BMI or military press and pull-over. Back squat (p = 0.054; +33.0% ± 83.7%) and power clean (p = 0.056; +26.2% ± 49.0%) increases approached significance. Our findings indicate that EFVPs improved BC and strength despite a dietary intake different from recommendations. This is possibly due to different substrate utilization during exercise in females versus males, thus new recommendations should be considered for high-intensity athletes, which are sex-specific.

  11. Strength of Fibrous Composites

    CERN Document Server

    Huang, Zheng-Ming

    2012-01-01

    "Strength of Fibrous Composites" addresses evaluation of the strength of a fibrous composite by using its constituent material properties and its fiber architecture parameters. Having gone through the book, a reader is able to predict the progressive failure behavior and ultimate strength of a fibrous laminate subjected to an arbitrary load condition in terms of the constituent fiber and matrix properties, as well as fiber geometric parameters. The book is useful to researchers and engineers working on design and analysis for composite materials. Dr. Zheng-Ming Huang is a professor at the School of Aerospace Engineering & Applied Mechanics, Tongji University, China. Mr. Ye-Xin Zhou is a PhD candidate at the Department of Mechanical Engineering, the University of Hong Kong, China.

  12. Postmenopausal HRT and tibolone in relation to muscle strength and body composition

    NARCIS (Netherlands)

    Jacobsen, D. E.; Samson, M. M.; Kezic, S.; Verhaar, H. J. J.

    2007-01-01

    Objectives: Sarcopenia, the loss of muscle mass with age, has a great impact on physical function, and especially in postmenopausal women, who experience a greater decline in muscle strength than do men of similar age. Conventional hormone replacement therapy (HRT) may diminish this loss of muscle

  13. Relationship between body composition, leg strength, anaerobic power, and on-ice skating performance in division I men's hockey athletes.

    Science.gov (United States)

    Potteiger, Jeffrey A; Smith, Dean L; Maier, Mark L; Foster, Timothy S

    2010-07-01

    The purpose of this study was to examine relationships between laboratory tests and on-ice skating performance in division I men's hockey athletes. Twenty-one men (age 20.7 +/- 1.6 years) were assessed for body composition, isokinetic force production in the quadriceps and hamstring muscles, and anaerobic muscle power via the Wingate 30-second cycle ergometer test. Air displacement plethysmography was used to determine % body fat (%FAT), fat-free mass (FFM), and fat mass. Peak torque and total work during 10 maximal effort repetitions at 120 degrees .s were measured during concentric muscle actions using an isokinetic dynamometer. Muscle power was measured using a Monark cycle ergometer with resistance set at 7.5% of body mass. On-ice skating performance was measured during 6 timed 89-m sprints with subjects wearing full hockey equipment. First length skate (FLS) was 54 m, and total length skate (TLS) was 89 m with fastest and average skating times used in the analysis. Correlation coefficients were used to determine relationships between laboratory testing and on-ice performance. Subjects had a body mass of 88.8 +/- 7.8 kg and %FAT of 11.9 +/- 4.6. First length skate-Average and TLS-Average skating times were moderately correlated to %FAT ([r = 0.53; p = 0.013] and [r = 0.57; p = 0.007]) such that a greater %FAT was related to slower skating speeds. First length skate-Fastest was correlated to Wingate percent fatigue index (r = -0.48; p = 0.027) and FLS-Average was correlated to Wingate peak power per kilogram body mass (r = -0.43; p = 0.05). Laboratory testing of select variables can predict skating performance in ice hockey athletes. This information can be used to develop targeted and effective strength and conditioning programs that will improve on-ice skating speed.

  14. Body composition of 80-years old men and women and its relation to muscle strength, physical activity and functional ability

    DEFF Research Database (Denmark)

    Pedersen, Agnes Nadelmann; Ovesen, L.; Schroll, M.

    2002-01-01

    , and physical activity and functional ability. BMI was related to body fat mass, and FFM was related to muscle strength. Muscle strength was related to mobility and PPT. Mobility and PPT were mutually related and were related to physical activity. CONCLUSION: Our cross sectional study did not support newly...

  15. Short rest interval lengths between sets optimally enhance body composition and performance with 8 weeks of strength resistance training in older men.

    Science.gov (United States)

    Villanueva, Matthew G; Lane, Christianne Joy; Schroeder, E Todd

    2015-02-01

    To determine if 8 weeks of periodized strength resistance training (RT) utilizing relatively short rest interval lengths (RI) in between sets (SS) would induce greater improvements in body composition and muscular performance, compared to the same RT program utilizing extended RI (SL). 22 male volunteers (SS: n = 11, 65.6 ± 3.4 years; SL: n = 11, 70.3 ± 4.9 years) were assigned to one of two strength RT groups, following 4 weeks of periodized hypertrophic RT (PHRT): strength RT with 60-s RI (SS) or strength RT with 4-min RI (SL). Prior to randomization, all 22 study participants trained 3 days/week, for 4 weeks, targeting hypertrophy; from week 4 to week 12, SS and SL followed the same periodized strength RT program for 8 weeks, with RI the only difference in their RT prescription. Following PHRT, all study participants experienced increases in lean body mass (LBM) (p body strength (p body fat (p high-intensity strength RT with shortened RI induces significantly greater enhancements in body composition, muscular performance, and functional performance, compared to the same RT prescription with extended RI, in older men. Applied professionals may optimize certain RT-induced adaptations, by incorporating shortened RI.

  16. Effect of floorball training on blood lipids, body composition, muscle strength, and functional capacity of elderly men.

    Science.gov (United States)

    Vorup, J; Pedersen, M T; Melcher, P S; Dreier, R; Bangsbo, J

    2017-11-01

    Floorball training consists of intense repeated exercise and may offer a motivating and social stimulating team activity in elderly individuals. However, the effect of floorball training in elderly adults on physiological adaptations important for health is not known. Thus, this study examined the effect of floorball training on blood lipids, muscle strength, body composition, and functional capacity of men aged 65-76 years. Thirty-nine recreational active men were randomized into a floorball group (FG; n = 22) or petanque group (PG; n = 17), in which training was performed 1 h twice a week for 12 weeks. In FG and PG, average heart rate (HR) during training was 80% and 57%, respectively, of maximal HR. In FG, plasma low-density lipoprotein (LDL) cholesterol and triglycerides were 11% and 8% lower (P functional capacity tests were better (P training period. No changes were observed in PG. In conclusion, 12 weeks of floorball training resulted in a number of favorable effects important for health and functional capacity, suggesting that floorball training can be used as a health-promoting activity in elderly men. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. The effects of a 6-month resistance training and dried plum consumption intervention on strength, body composition, blood markers of bone turnover, and inflammation in breast cancer survivors.

    Science.gov (United States)

    Simonavice, Emily; Liu, Pei-Yang; Ilich, Jasminka Z; Kim, Jeong-Su; Arjmandi, Bahram; Panton, Lynn B

    2014-06-01

    The purpose of this study was to examine the effects of resistance training (RT) and dried plum (DP) consumption on strength, body composition, blood markers of bone, and inflammation in breast cancer survivors (BCS). Twenty-three BCS (RT, n = 12; RT+DP, n = 11), aged 64 ± 7 years, were evaluated at baseline and after 6 months of intervention on the following: muscular strength (chest press and leg extension) via 1-repetition maximums (1RMs); body composition, specifically bone mineral density (BMD) by dual energy X-ray absorptiometry; biochemical markers of bone turnover (bone-specific alkaline phosphatase (BAP), tartrate resistant acid phosphatase (TRAP-5b)); and inflammation (C-reactive protein (CRP)). Target RT prescription was 2 days/week of 10 exercises, including 2 sets of 8-12 repetitions at ∼60%-80% of 1RM. RT+DP also consumed 90 g of DP daily. There were no baseline differences between groups or any group-by-time interactions for any of the variables. BCS increased upper (p body strength. Body composition and BMD improvements were not observed. TRAP-5b decreased in the RT group (p body composition and biochemical markers of inflammation.

  18. The effect of neuromuscular electrical stimulation on muscle strength, functional capacity and body composition in haemodialysis patients

    Directory of Open Access Journals (Sweden)

    Vicent Esteve

    2017-01-01

    Conclusions: (1 NMES improved muscle strength, functional capacity and quadriceps muscle composition in our patients. (2 Based on the results obtained, NMES could be a new therapeutic alternative to prevent muscle atrophy and progressive physical deterioration. (3 However, future studies are necessary to establish the potential beneficial effects of NMES in HD patients.

  19. Strength and muscle quality in a well-functioning cohort of older adults : the Health, Aging and Body Composition Study

    NARCIS (Netherlands)

    Newman, Anne B; Haggerty, Catherine L; Goodpaster, Bret H; Harris, Tamara B; Kritchevsky, Steve; Nevitt, Michael; Miles, Toni P; Visser, Marjolein

    OBJECTIVES: To determine whether lower lean mass and higher fat mass have independent effects on the loss of strength and muscle quality in older adults and might explain part of the effect of age. DESIGN: Single-episode, cross-sectional analyses of a cohort of subjects in the Health, Aging and Body

  20. Eight Weeks of Phosphatidic Acid Supplementation in Conjunction with Resistance Training Does Not Differentially Affect Body Composition and Muscle Strength in Resistance-Trained Men

    Directory of Open Access Journals (Sweden)

    Thomas L. Andre, Joshua J. Gann, Sarah K. McKinley-Barnard, Joon J. Song, Darryn S. Willoughby

    2016-09-01

    Full Text Available This study attempted to determine the effects of eight weeks of resistance training (RT combined with phosphatidic acid (PA supplementation at a dose of either 250 mg or 375 mg on body composition and muscle size and strength. Twenty-eight resistance-trained men were randomly assigned to ingest 375 mg [PA375 (n = 9] or 250 mg [PA250 (n = 9] of PA or 375 mg of placebo [PLC (n = 10] daily for eight weeks with RT. Supplements were ingested 60 minutes prior to RT and in the morning on non-RT days. Participants’ body composition, muscle size, and lower-body muscle strength were determined before and after training/supplementation. Separate group x time ANOVAs for each criterion variable were used employing an alpha level of ≤ 0.05. Magnitude- based inferences were utilized to determine the likely or unlikely impact of PA on each criterion variable. A significant main effect for time was observed for improvements in total body mass (p = 0.003, lean mass (p = 0.008, rectus femoris cross-sectional area [RF CSA (p = 0.011], and lower-body strength (p 0.05. Collectively, magnitude-based inferences determined both doses of PA to have a likely impact of increasing body mass (74.2%, lean mass (71.3%, RF CSA (92.2%, and very likely impact on increasing lower-body strength (98.1% beneficial. When combined with RT, it appears that PA has a more than likely impact on improving lower-body strength, whereas a likely impact exists for increasing muscle size and lean mass.

  1. Effect of physical exercise training on muscle strength and body composition, and their association with functional capacity and quality of life in patients with atrial fibrillation

    DEFF Research Database (Denmark)

    Osbak, Philip Samuel; Mourier, Malene; Henriksen, Jens Henrik

    2012-01-01

    Objective: Atrial fibrillation diminishes cardiac function, exercise tolerance and quality of life. The objective of this study was to determine whether exercise training in atrial fibrillation affects muscle strength, body composition, maximal exercise capacity and walking capacity positively......, thus improving quality of life. Design: Randomized clinical trial. Twelve weeks of physical exercise training or control. Patients: Forty-nine patients in permanent atrial fibrillation were randomized to training or control. Methods: Intervention consisted of aerobic training for 1 h 3 times per week...... at 70% of maximal exercise capacity vs control. Muscle strength, exercise capacity, 6-minute walk test, lean body mass, fat percentage, and quality of life were assessed. Results: Muscle strength increased in the training group (p = 0.01), but no change was observed in controls. Lean body mass...

  2. Can resistance training change the strength, body composition and self-concept of overweight and obese adolescent males? A randomised controlled trial.

    Science.gov (United States)

    Schranz, Natasha; Tomkinson, Grant; Parletta, Natalie; Petkov, John; Olds, Tim

    2014-10-01

    Resistance training is an exercise modality at which overweight and obese adolescents can excel and which can therefore positively affect their psychological well-being. The aim of this study was to determine the effect of a 6-month resistance training intervention on the self-concept strength and body composition of overweight and obese adolescent males. 56 overweight and obese males aged 13-17 years were randomly allocated to an Intervention (n=30) or Control (n=26) group. Primary (psychological) and secondary (strength and body composition) outcomes were assessed at baseline as well as at 3 (halfway through the intervention), 6 (immediately postintervention) and 12 months follow-up. Random effects mixed modelling was used to determine the effects of the intervention. Statistically significant differences between the Intervention and Control groups were observed at 3-month and 6-month assessments for exercise self-efficacy, resistance training confidence and self-esteem. Large increases in strength for the Intervention group, relative to Controls, were also observed with no substantial changes in body composition shown for either group. Values for all variables returned to baseline following completion of the programme. A 6-month resistance training intervention can positively affect the self-concept and strength of overweight and obese adolescent boys. 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.

  3. Are unilateral and bilateral patellar tendinopathy distinguished by differences in anthropometry, body composition, or muscle strength in elite female basketball players?

    Science.gov (United States)

    Gaida, J E; Cook, J L; Bass, S L; Austen, S; Kiss, Z S

    2004-10-01

    Overuse injury to the patellar tendon (patellar tendinopathy) is a major reason for interrupted training and competition for elite athletes. In both sexes, the prevalence of unilateral and bilateral tendinopathy has been shown to differ. It has been proposed that bilateral pathology may have a different aetiology from unilateral pathology. Investigation of risk factors that may be unique to unilateral and bilateral patellar tendinopathy in female athletes may reveal insights into the aetiology of this condition. To examine whether anthropometry, body composition, or muscle strength distinguished elite female basketball players with unilateral or bilateral patellar tendinopathy. Body composition, anthropometry, and muscle strength were compared in elite female basketball players with unilateral (n = 8), bilateral (n = 7), or no (n = 24) patellar tendinopathy. Body composition was analysed using a dual energy x ray absorptiometer. Anthropometric measures were assessed using standard techniques. Knee extensor strength was measured at 180 degrees /s using an isokinetic dynamometer. z scores were calculated for the unilateral and bilateral groups (using the no tendinopathy group as controls). z scores were tested against zero. The tibia length to stature ratio was approximately 1.3 (1.3) SDs above zero in both the affected and non-affected legs in the unilateral group (ppatellar tendinopathy has identifiable risk factors whereas bilateral patellar tendinopathy may not. This suggests that the aetiology of these conditions may be different. However, interpretation must respect the limitation of small subject numbers.

  4. The effects of a commercially available botanical supplement on strength, body composition, power output, and hormonal profiles in resistance-trained males

    Directory of Open Access Journals (Sweden)

    Kreider Richard

    2010-10-01

    Full Text Available Abstract Background Fenugreek (Trigonella foenum-graecum is a leguminous, annual plant originating in India and North Africa. In recent years Fenugreek has been touted as an ergogenic aid. The purpose of this study was to evaluate the effects of Fenugreek supplementation on strength and body composition. Methods 49 Resistance trained men were matched according to body weight and randomly assigned to ingest in a double blind manner capsules containing 500 mg of a placebo (N = 23, 20 ± 1.9 years, 178 ± 6.3 cm, 85 ± 12.7 kg, 17 ± 5.6 %BF or Fenugreek (N = 26, 21 ± 2.8 years, 178 ± 6 cm, 90 ± 18.2 kg, 19.3 ± 8.4 %BF. Subjects participated in a supervised 4-day per week periodized resistance-training program split into two upper and two lower extremity workouts per week for a total of 8-weeks. At 0, 4, and 8-weeks, subjects underwent hydrodensiometery body composition, 1-RM strength, muscle endurance, and anaerobic capacity testing. Data were analyzed using repeated measures ANOVA and are presented as mean ± SD changes from baseline after 60-days. Results No significant differences (p > 0.05 between groups were noted for training volume. Significant group × time interaction effects were observed among groups in changes in body fat (FEN: -2.3 ± 1.4%BF; PL: -0.39 ± 1.6 %BF, p 0.05. Conclusion It is concluded that 500 mg of this proprietary Fenugreek extraction had a significant impact on both upper- and lower-body strength and body composition in comparison to placebo in a double blind controlled trial. These changes were obtained with no clinical side effects.

  5. Comparisons of low-intensity versus moderate-intensity combined aerobic and resistance training on body composition, muscle strength, and functional performance in older women.

    Science.gov (United States)

    Shiotsu, Yoko; Yanagita, Masahiko

    2018-06-01

    This study aimed to examine the effects of exercise order of combined aerobic and low- or moderate-intensity resistance training into the same session on body composition, functional performance, and muscle strength in healthy older women. Furthermore, this study compared the effects of different (low- vs moderate-) intensity combined training. A total of 60 healthy older women (age 61-81 y) were randomly assigned to five groups that performed aerobic exercise before low-intensity resistance training (AR-L, n = 12) or after resistance training (RA-L, n = 12), performed aerobic exercise before moderate-intensity resistance training (AR-M, n = 12) or after resistance training (RA-M, n = 12), or nonintervention control conditions (CON, n = 12). Body composition, functional performance, and muscle strength were evaluated before and after the 10-week training. No effects of exercise order of combined aerobic and low- or moderate-intensity resistance training (AR-L vs RA-L, AR-M vs RA-M) were observed in body composition, functional performance, or muscle strength, whereas the effects of training intensity of combined training (AR-L vs AR-M, RA-L vs RA-M) were observed on functional performance. All combined trainings significantly increased muscle strength and gait ability (P Functional reach test significantly increased in the AR-M and RA-M groups (P training increases muscle strength and improves gait ability, regardless of the exercise order. Also, greater improvement in dynamic balance capacity, a risk factor associated with falling, is observed in moderate-intensity combined training.

  6. Programming and supervision of resistance training leads to positive effects on strength and body composition: results from two randomised trials of community fitness programmes.

    Science.gov (United States)

    Mann, Steven; Jimenez, Alfonso; Steele, James; Domone, Sarah; Wade, Matthew; Beedie, Chris

    2018-03-27

    studies across all RT treatments compared to controls, yet significant improvements in both strength and body-composition occurred only in programmed and/or supervised RT. As general increases in physical activity have limited impact upon body-composition, public health practitioners should structure interventions to include progressive RT. Study 1: ISRCTN13024854 , retrospectively registered 20/02/2018. Study 2: ISRCTN13509468 , retrospectively registered 20/02/2018).

  7. Comparative analysis between two models of active aging and its influence on body composition, strength levels and quality of life: long-distance runners versus bodybuilders practitioners.

    Science.gov (United States)

    Latorre-Román, Pedro Ángel; Izquierdo-Sánchez, Jose Manuel; Salas-Sánchez, Jesús; García-Pinillos, Felipe

    2015-04-01

    To analyze the body composition, strength level, and the quality of life related to the health (QoL) in veteran sportsmen (>35 years old) in relation to sedentary ones (S), and to compare the result in the mentioned variables between two models of sports practice, long-distance runners (LDR) and bodybuilding practitioners (BBP). One hundred forty-eight male participants took part and were distributed into three groups: 47 LDR (age=42.01±6.96 years), 49 BBP (age=45.14±7.04 years), and 47 S (age=43.71±8.75 years). Body composition, upper- and lower-limb strength level, and QoL were assessed. The LDR and BBP obtained better performance in countermovement jump (CMJ) than the S ones (+0.06 m, paging on body composition, the muscle mass is reduced in all groups controlled (LDR, BBP, and S). Additionally, the %fat mass is increased only in S group (pactive aging showed healthier values in BMI and %fat mass as well as greater results in QoL than BBP and S groups. Nevertheless, the LDR group showed similar values to S ones in muscle mass. The regression analysis performed showed that the sedentary habit predicts the %fat mass and CMJ performance. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  8. Functional High-Intensity Circuit Training Improves Body Composition, Peak Oxygen Uptake, Strength, and Alters Certain Dimensions of Quality of Life in Overweight Women.

    Science.gov (United States)

    Sperlich, Billy; Wallmann-Sperlich, Birgit; Zinner, Christoph; Von Stauffenberg, Valerie; Losert, Helena; Holmberg, Hans-Christer

    2017-01-01

    The effects of circuit-like functional high-intensity training (Circuit HIIT ) alone or in combination with high-volume low-intensity exercise (Circuit combined ) on selected cardio-respiratory and metabolic parameters, body composition, functional strength and the quality of life of overweight women were compared. In this single-center, two-armed randomized, controlled study, overweight women performed 9-weeks (3 sessions·wk -1 ) of either Circuit HIIT ( n = 11), or Circuit combined ( n = 8). Peak oxygen uptake and perception of physical pain were increased to a greater extent ( p body mass, body-mass-index, waist-to-hip ratio, fat mass, and enhanced fat-free mass; decreased ratings of perceived exertion during submaximal treadmill running; improved the numbers of push-ups, burpees, one-legged squats, and 30-s skipping performed, as well as the height of counter-movement jumps; and improved physical and social functioning, role of physical limitations, vitality, role of emotional limitations, and mental health to a similar extent (all p training can be employed to improve body composition, selected variables of functional strength, and certain dimensions of quality of life in overweight women. However, Circuit HIIT improves peak oxygen uptake to a greater extent, but with more perception of pain, whereas Circuit combined results in better perception of general health.

  9. Resistance Training with Single vs. Multi-joint Exercises at Equal Total Load Volume: Effects on Body Composition, Cardiorespiratory Fitness, and Muscle Strength.

    Science.gov (United States)

    Paoli, Antonio; Gentil, Paulo; Moro, Tatiana; Marcolin, Giuseppe; Bianco, Antonino

    2017-01-01

    The present study aimed to compare the effects of equal-volume resistance training performed with single-joint (SJ) or multi-joint exercises (MJ) on VO 2 max, muscle strength and body composition in physically active males. Thirty-six participants were divided in two groups: SJ group ( n = 18, 182.1 ± 5.2, 80.03 ± 2.78 kg, 23.5 ± 2.7 years) exercised with only SJ exercises (e.g., dumbbell fly, knee extension, etc.) and MJ group ( n = 18, 185.3 ± 3.6 cm, 80.69 ± 2.98 kg, 25.5 ± 3.8 years) with only MJ exercises (e.g., bench press, squat, etc.). The total work volume (repetitions × sets × load) was equated between groups. Training was performed three times a week for 8 weeks. Before and after the training period, participants were tested for VO 2 max, body composition, 1 RM on the bench press, knee extension and squat. Analysis of covariance (ANCOVA) was used to compare post training values between groups, using baseline values as covariates. According to the results, both groups decreased body fat and increased fat free mass with no difference between them. Whilst both groups significantly increased cardiorespiratory fitness and maximal strength, the improvements in MJ group were higher than for SJ in VO 2 max (5.1 and 12.5% for SJ and MJ), bench press 1 RM (8.1 and 10.9% for SJ and MJ), knee extension 1 RM (12.4 and 18.9% for SJ and MJ) and squat 1 RM (8.3 and 13.8% for SJ and MJ). In conclusion, when total work volume was equated, RT programs involving MJ exercises appear to be more efficient for improving muscle strength and maximal oxygen consumption than programs involving SJ exercises, but no differences were found for body composition.

  10. Zooplankton body composition

    DEFF Research Database (Denmark)

    Kiørboe, Thomas

    2013-01-01

    groups body composition is size independent. Exceptions are protozoans, chaetognaths, and pteropods, where larger individuals become increasingly watery. I speculate about the dichotomy in body composition and argue that differences in feeding mechanisms and predator avoidance strategies favor either......I compiled literature on zooplankton body composition, from protozoans to gelatinous plankton, and report allometric relations and average body composition. Zooplankton segregate into gelatinous and non-gelatinous forms, with few intermediate taxa (chaetognaths, polychaetes, and pteropods). In most...... a watery or a condensed body form, and that in the intermediate taxa the moderately elevated water content is related to buoyancy control and ambush feeding...

  11. Functional High-Intensity Circuit Training Improves Body Composition, Peak Oxygen Uptake, Strength, and Alters Certain Dimensions of Quality of Life in Overweight Women

    OpenAIRE

    Sperlich, Billy; Wallmann-Sperlich, Birgit; Zinner, Christoph; Von Stauffenberg, Valerie; Losert, Helena; Holmberg, Hans-Christer

    2017-01-01

    Source at https://doi.org/10.3389/fphys.2017.00172 The effects of circuit-like functional high-intensity training (CircuitHIIT) alone or in combination with high-volume low-intensity exercise (Circuitcombined) on selected cardio-respiratory and metabolic parameters, body composition, functional strength and the quality of life of overweight women were compared. In this single-center, two-armed randomized, controlled study, overweight women performed 9-weeks (3 sessions·wk−1) of either Ci...

  12. The effect of energy-protein supplementation on weight, body composition and handgrip strength among pulmonary tuberculosis HIV-co-infected patients

    DEFF Research Database (Denmark)

    PrayGod, George; Range, Nyagosya; Faurholt-Jepsen, Daniel

    2012-01-01

    Undernutrition is common among smear-positive pulmonary tuberculosis (PTB+) patients. Micronutrient supplementation may improve treatment outcomes, but it is unclear whether additional energy-protein would be beneficial. The present study aimed to assess the effect of energy-protein supplementation...... on weight, body composition and handgrip strength against a background of high micronutrient intake during tuberculosis (TB) treatment. A total of 377 PTB+ patients co-infected with HIV were randomly allocated one or six biscuits daily for 60 d during TB treatment. Weight, arm fat area, arm muscle area...

  13. The loss of skeletal muscle strength, mass, and quality in older adults : the health, aging and body composition study

    NARCIS (Netherlands)

    Goodpaster, Bret H; Park, Seok Won; Harris, Tamara B; Kritchevsky, Steven B; Nevitt, Michael; Schwartz, Ann V; Simonsick, Eleanor M; Tylavsky, Frances A; Visser, Marjolein; Newman, Anne B

    2006-01-01

    BACKGROUND: The loss of muscle mass is considered to be a major determinant of strength loss in aging. However, large-scale longitudinal studies examining the association between the loss of mass and strength in older adults are lacking. METHODS: Three-year changes in muscle mass and strength were

  14. Differential effects of strength training and testosterone treatment on soluble CD36 in aging men: Possible relation to changes in body composition

    DEFF Research Database (Denmark)

    Glintborg, Dorte; Christensen, Louise L; Kvorning, Thue

    2015-01-01

    Purpose. We measured soluble CD36 (sCD36) and body composition to determine the effects of testosterone treatment (TT) and/or strength training (ST) on cardiovascular risk in men with low normal testosterone levels. Methods. Double-blinded, placebo-controlled study in 54 men aged 60-78 years...... with bioavailable testosterone 94 cm randomized to TT (gel, 50-100 mg/day, n = 20), placebo (n = 18) or ST (n = 16) for 6 months. Moreover, the ST group was randomized to TT (ST + TT, n = 7) or placebo (ST + placebo, n = 9) after 3 months. Outcomes. sCD36, total and regional fat mass were....... units] vs. TT and vs. placebo (p testosterone and lean body mass. Fat mass measures significantly improved during ST + placebo, ST + TT, and TT vs. placebo. During ST + placebo, delta sCD36 was associated with delta total fat mass (r = 0.81) and delta...

  15. Impact of Four Weeks of a Multi-Ingredient Performance Supplement on Muscular Strength, Body Composition, and Anabolic Hormones in Resistance-Trained Young Men.

    Science.gov (United States)

    Kreipke, Vince C; Allman, Brittany R; Kinsey, Amber W; Moffatt, Robert J; Hickner, Robert C; Ormsbee, Michael J

    2015-12-01

    Although multi-ingredient performance supplements (MIPS) have increased in popularity because of their array of ergogenic ingredients, their efficacy and safety remain in question. The objective of this study was to determine the impact of supplementation with T+ (SUP; Onnit Labs, Austin, TX, USA), an MIPS containing long jack root, beta-alanine, and branched-chain amino acids, and other proprietary blends, on strength, body composition, and hormones in young resistance-trained men. Subjects were randomized to consume either T+ (SUP; n = 14; age, 21 ± 3 years; body fat, 18.3 ± 4.7%) or an isocaloric placebo (PL; n = 13; age, 21 ± 3 years; body fat, 21.5 ± 6.2%) for 4 weeks. Both groups underwent a progressive, 4-week high-intensity resistance training protocol. Before and after the training protocol, mood state, body composition, blood hormones (also collected at midpoint), and maximal strength were measured. SUP had significantly greater increases in bench press (SUP, 102 ± 16 kg to 108 ± 16 kg vs. PL, 96 ± 22 kg to 101 ± 22 kg; p < 0.001) and total weight lifted (SUP, 379 ± 59 kg to 413 ± 60 kg vs. PL, 376 ± 70 kg to 400 ± 75 kg; p < 0.001) compared with PL. Additionally, deadlift strength relative to total body mass (calculated as weight lifted/body mass; kg:kg) (2.08 ± 0.18 to 2.23 ± 0.16; p = 0.036) and lean mass (2.55 ± 0.19 to 2.72 ± 0.16; p = 0.021) increased significantly in SUP but not PL (2.02 ± 0.30 to 2.15 ± 0.36 and 2.56 ± 0.31 to 2.70 ± 0.36, respectively). No other significant differences were detected between groups for the remaining variables. Supplementing with SUP enhanced resistance training adaptations independent of hormonal status, and thus SUP use may warrant inclusion into peri-workout nutrition regimens. This study was registered with clinicaltrials.gov (identifier: NCT01971723).

  16. Resistance Training with Single vs. Multi-joint Exercises at Equal Total Load Volume: Effects on Body Composition, Cardiorespiratory Fitness, and Muscle Strength

    Directory of Open Access Journals (Sweden)

    Antonio Paoli

    2017-12-01

    Full Text Available The present study aimed to compare the effects of equal-volume resistance training performed with single-joint (SJ or multi-joint exercises (MJ on VO2max, muscle strength and body composition in physically active males. Thirty-six participants were divided in two groups: SJ group (n = 18, 182.1 ± 5.2, 80.03 ± 2.78 kg, 23.5 ± 2.7 years exercised with only SJ exercises (e.g., dumbbell fly, knee extension, etc. and MJ group (n = 18, 185.3 ± 3.6 cm, 80.69 ± 2.98 kg, 25.5 ± 3.8 years with only MJ exercises (e.g., bench press, squat, etc.. The total work volume (repetitions × sets × load was equated between groups. Training was performed three times a week for 8 weeks. Before and after the training period, participants were tested for VO2max, body composition, 1 RM on the bench press, knee extension and squat. Analysis of covariance (ANCOVA was used to compare post training values between groups, using baseline values as covariates. According to the results, both groups decreased body fat and increased fat free mass with no difference between them. Whilst both groups significantly increased cardiorespiratory fitness and maximal strength, the improvements in MJ group were higher than for SJ in VO2max (5.1 and 12.5% for SJ and MJ, bench press 1 RM (8.1 and 10.9% for SJ and MJ, knee extension 1 RM (12.4 and 18.9% for SJ and MJ and squat 1 RM (8.3 and 13.8% for SJ and MJ. In conclusion, when total work volume was equated, RT programs involving MJ exercises appear to be more efficient for improving muscle strength and maximal oxygen consumption than programs involving SJ exercises, but no differences were found for body composition.

  17. The effect of five weeks of Tribulus terrestris supplementation on muscle strength and body composition during preseason training in elite rugby league players.

    Science.gov (United States)

    Rogerson, Shane; Riches, Christopher J; Jennings, Carl; Weatherby, Robert P; Meir, Rudi A; Marshall-Gradisnik, Sonya M

    2007-05-01

    Tribulus terrestris is an herbal nutritional supplement that is promoted to produce large gains in strength and lean muscle mass in 5-28 days (15, 18). Although some manufacturers claim T. terrestris will not lead to a positive drug test, others have suggested that T. terrestris may increase the urinary testosterone/epitestosterone (T/E) ratio, which may place athletes at risk of a positive drug test. The purpose of the study was to determine the effect of T. terrestris on strength, fat free mass, and the urinary T/E ratio during 5 weeks of preseason training in elite rugby league players. Twenty-two Australian elite male rugby league players (mean +/- SD; age = 19.8 +/- 2.9 years; weight = 88.0 +/- 9.5 kg) were match-paired and randomly assigned in a double-blind manner to either a T. terrestris (n = 11) or placebo (n = 11) group. All subjects performed structured heavy resistance training as part of the club's preseason preparations. A T. terrestris extract (450 mg.d(-1)) or placebo capsules were consumed once daily for 5 weeks. Muscular strength, body composition, and the urinary T/E ratio were monitored prior to and after supplementation. After 5 weeks of training, strength and fat free mass increased significantly without any between-group differences. No between-group differences were noted in the urinary T/E ratio. It was concluded that T. terrestris did not produce the large gains in strength or lean muscle mass that many manufacturers claim can be experienced within 5-28 days. Furthermore, T. terrestris did not alter the urinary T/E ratio and would not place an athlete at risk of testing positive based on the World Anti-Doping Agency's urinary T/E ratio limit of 4:1.

  18. The Effect of a 12-Week Omega-3 Supplementation on Body Composition, Muscle Strength and Physical Performance in Elderly Individuals with Decreased Muscle Mass

    Directory of Open Access Journals (Sweden)

    Roma Krzymińska-Siemaszko

    2015-08-01

    Full Text Available The aim of the study was to assess the effect of a polyunsaturated omega-3 fatty acids (PUFA supplementation on the parameters of body composition, muscle strength and physical performance in elderly people with decreased muscle mass (DMM. Fifty three elderly people with an ALM index (the ratio of appendicular lean mass to squared height either below (−2SD: low muscle mass-LMM or between (−1SD and −2SD: the risk of LMM-rLMM the ALM index for the young Polish reference population were randomly assigned to PUFA-treated groups (LMM-PUFA, rLMM-PUFA or control groups (LMM-control, rLMM-control. PUFA-treated groups received capsules containing 1.3 g of PUFA and 10 mg of vitamin E, while the control groups received 11 mg of vitamin E daily for 12 weeks. Body composition (BIA analysis, muscle strength (hand grip measured with dynamometer and physical performance (Timed Up and Go test-TUG were assessed before and after supplementation. No statistically significant differences were observed either in muscle mass or in the hand grip and TUG in any group. The post-pre difference (mean ± SD in ALM index was as follows (kg/m2: LMM-PUFA: 0.00 ± 0.30, rLMM-PUFA: 0.00 ± 0.22, LMM-control: 0.03 ± 0.36, rLMM-control: –0.03 ± 0.20. In our study, a 12 week supplementation of PUFA did not affect the evaluated parameters in elderly individuals with DMM.

  19. Body composition and wages.

    Science.gov (United States)

    Wada, Roy; Tekin, Erdal

    2010-07-01

    This paper examines the relationship between body composition and wages in the United States. We develop measures of body composition--body fat (BF) and fat-free mass (FFM)--using data on bioelectrical impedance analysis (BIA) that are available in the National Health and Nutrition Examination Survey III and estimate wage models for respondents in the National Longitudinal Survey of Youth 1979. Previous research uses body size or BMI as measures of obesity despite a growing concern that they do not distinguish between body fat and fat-free body mass or adequately control for non-homogeneity inside the human body. Therefore, measures presented in this paper represent a useful alternative to BMI-based proxies of obesity. Our results indicate that BF is associated with decreased wages for both males and females among whites and blacks. We also present evidence suggesting that FFM is associated with increased wages. We show that these results are not the artifacts of unobserved heterogeneity. Finally, our findings are robust to numerous specification checks and to a large number of alternative BIA prediction equations from which the body composition measures are derived. 2010 Elsevier B.V. All rights reserved.

  20. Resistance training-induced gains in muscle strength, body composition, and functional capacity are attenuated in elderly women with sarcopenic obesity

    Directory of Open Access Journals (Sweden)

    de Oliveira Silva A

    2018-03-01

    Full Text Available Alessandro de Oliveira Silva,1,2 Maurílio Tiradentes Dutra,3 Wilson Max Almeida Monteiro de Moraes,4 Silvana Schwerz Funghetto,3 Darlan Lopes de Farias,1 Paulo Henrique Fernandes dos Santos,3 Denis Cesar Leite Vieira,5 Dahan da Cunha Nascimento,4,5 Vânia Silva Macedo Orsano,4 Brad J Schoenfeld,6 Jonato Prestes4 1University Center of Brasilia (UniCEUB, Brasília, Brazil; 2Integrated Colleges of the Central Plateau Educational Union (FACIPLAC, Brasília, Brazil; 3University of Brasilia (UnB, Brasília, Brazil; 4Catholic University of Brasilia (UCB, Brasília, Brazil; 5University Center of the Federal District (UDF, Brasília, Brazil; 6Department of Health Sciences, CUNY Lehman College, Bronx, NY, United States Objectives: The purpose of this study was to compare the effects of resistance training (RT on body composition, muscle strength, and functional capacity in elderly women with and without sarcopenic obesity (SO.Methods: A total of 49 women (aged ≥60 years were divided in two groups: without SO (non-SO, n=41 and with SO (n=8. Both groups performed a periodized RT program consisting of two weekly sessions for 16 weeks. All measures were assessed at baseline and postintervention, including anthropometry and body composition (dual-energy X-ray absorptiometry, muscle strength (one repetition maximum for chest press and 45° leg press, and functional capacity (stand up, elbow flexion, timed “up and go”.Results: After the intervention, only the non-SO group presented significant reductions in percentage body fat (-2.2%; P=0.006, waist circumference (-2.7%; P=0.01, waist-to-hip ratio (-2.3; P=0.02, and neck circumference (-1.8%; P=0.03 as compared with baseline. Muscle strength in the chest press and biceps curl increased in non-SO only (12.9% and 11.3%, respectively, while 45° leg press strength increased in non-SO (50.3% and SO (40.5% as compared with baseline. Performance in the chair stand up and timed “up and go” improved in non

  1. Effects of High vs. Low Protein Intake on Body Composition and Maximal Strength in Aspiring Female Physique Athletes Engaging in an 8-Week Resistance Training Program.

    Science.gov (United States)

    Campbell, Bill I; Aguilar, Danielle; Conlin, Laurin; Vargas, Andres; Schoenfeld, Brad Jon; Corson, Amey; Gai, Chris; Best, Shiva; Galvan, Elfego; Couvillion, Kaylee

    2018-02-06

    Aspiring female physique athletes are often encouraged to ingest relatively high levels of dietary protein in conjunction with their resistance-training programs. However, there is little to no research investigating higher vs. lower protein intakes in this population. This study examined the influence of a high vs. low protein diet in conjunction with an 8-week resistance training program in this population. Seventeen females (21.2±2.1 years; 165.1±5.1 cm; 61±6.1 kg) were randomly assigned to a high protein diet (HP: 2.5g/kg/day; n=8) or a low protein diet (LP: 0.9g/kg/day, n=9) and were assessed for body composition and maximal strength prior to and after the 8-week protein intake and exercise intervention. Fat-free mass (FFM) increased significantly more in the HP group as compared to the LP group (p=0.009), going from 47.1 ± 4.5kg to 49.2 ± 5.4kg (+2.1kg) and from 48.1 ± 2.7kg to 48.7 ± 2 (+0.6kg) in the HP and LP groups, respectively. Fat mass significantly decreased over time in the HP group (14.1 ± 3.6kg to 13.0 ± 3.3kg; p<0.01) but no change was observed in the LP group (13.2 ± 3.7kg to 12.5 ± 3.0kg). While maximal strength significantly increased in both groups, there were no differences in strength improvements between the two groups. In aspiring female physique athletes, a higher protein diet is superior to a lower protein diet in terms of increasing FFM in conjunction with a resistance training program.

  2. Relations of meeting national public health recommendations for muscular strengthening activities with strength, body composition, and obesity: the Women's Injury Study.

    Science.gov (United States)

    Trudelle-Jackson, Elaine; Jackson, Allen W; Morrow, James R

    2011-10-01

    We examined the relations of meeting or not meeting the 2008 Physical Activity Guidelines for Americans recommendations for muscular strengthening activities with percentage of body fat, body mass index (BMI; defined as weight in kilograms divided by height in meters, squared), muscular strength, and obesity classification in women. We analyzed data on 918 women aged 20 to 83 years in the Women's Injury Study from 2007 to 2009. A baseline orthopedic examination included measurement of height, body weight, skinfolds, and muscle strength. Women who met muscle strengthening activity recommendations had significantly lower BMI and percentage of body fat and higher muscle strength. Women not meeting those recommendations were more likely to be obese (BMI ≥ 30) compared with women who met the recommendations after we adjusted for age, race, and aerobic physical activity (odds ratio = 2.28; 95% confidence interval = 1.61, 3.23). There was a small but significant positive association between meeting muscle strengthening activity recommendations and muscular strength, a moderate inverse association with body fat percentage, and a strong inverse association with obesity classification, providing preliminary support for the muscle strengthening activity recommendation for women.

  3. Evaluation of resistance training to improve muscular strength and body composition in cancer patients undergoing neoadjuvant and adjuvant therapy: a meta-analysis.

    Science.gov (United States)

    Padilha, Camila S; Marinello, Poliana Camila; Galvão, Daniel A; Newton, Robert U; Borges, Fernando H; Frajacomo, Fernando; Deminice, Rafael

    2017-06-01

    Muscle atrophy and strength decline are two of the most prominent characteristics in cancer patients undergoing cancer therapy, leading to decreased functional ability and reduced quality of life. Therefore, the aim is to systematically review research evidence of the effects of resistance exercise (RE) on lower-limb muscular strength, lean body mass (LBM), and body fat (BF) in cancer patients undertaking neoadjuvant or adjuvant therapy. This research was conducted using the following online database: Clinical Trial Register, Cochrane Trial Register, PubMed, SPORT Discus, and SciELO, from September 2014 until May 2015. We used the following keywords in various combinations with a systematic search: "Cancer therapy," "Wasting muscle," "Muscle loss," "Muscle function," "Neoadjuvant therapy," "Adjuvant thera-py," "Resistance Training," "Weight training," and "Exercise." After selection of 272 full-text articles, 14 publications were included in this meta-analysis. Resistance exercise (RE) during neoadjuvant or adjuvant therapy increased lower-limb muscular strength (mean: 26.22 kg, 95% CI [16.01, 36.43], heterogeneity: P = body mass (LBM) increased (mean 0.8 kg, 95% CI [0.7, 0.9], heterogeneity: P = 0.99, I 2  = 0%, P body fat (BF) (mean: -1.3 kg, 95% CI [-1.5, 1.1], heterogeneity: P = 0.93, I 2  = 0%, P cancer patients undergoing neoadjuvant and adjuvant therapy regardless of the kind of treatment. RE increases muscle strength, maintains LBM, and reduces BF in cancer patients undergoing adjuvant and neoadjuvant therapies. Cancer patients and survivors should consider undertaking RE as an effective countermeasure for treatment-related adverse effects to the musculoskeletal system.

  4. D-aspartic acid supplementation combined with 28 days of heavy resistance training has no effect on body composition, muscle strength, and serum hormones associated with the hypothalamo-pituitary-gonadal axis in resistance-trained men.

    Science.gov (United States)

    Willoughby, Darryn S; Leutholtz, Brian

    2013-10-01

    It was hypothesized that D-aspartic acid (D-ASP) supplementation would not increase endogenous testosterone levels or improve muscular performance associated with resistance training. Therefore, body composition, muscle strength, and serum hormone levels associated with the hypothalamo-pituitary-gonadal axis were studied after 28 days of resistance training and D-ASP supplementation. Resistance-trained men resistance trained 4 times/wk for 28 days while orally ingesting either 3 g of placebo or 3 g of D-ASP. Data were analyzed with 2 × 2 analysis of variance (P aspartate oxidase (DDO) were determined. Body composition and muscle strength were significantly increased in both groups in response to resistance training (P .05). Total and free testosterone, luteinizing hormone, gonadotropin-releasing hormone, and estradiol were unchanged with resistance training and D-ASP supplementation (P > .05). For serum D-ASP and DDO, D-ASP resulted in a slight increase compared with baseline levels (P > .05). For the D-ASP group, the levels of serum DDO were significantly increased compared with placebo (P < .05). The gonadal hormones were unaffected by 28 days of D-ASP supplementation and not associated with the observed increases in muscle strength and mass. Therefore, at the dose provided, D-ASP supplementation is ineffective in up-regulating the activity of the hypothalamo-pituitary-gonadal axis and has no anabolic or ergogenic effects in skeletal muscle. © 2013 Elsevier Inc. All rights reserved.

  5. Accelerated Strength Testing of Thermoplastic Composites

    Science.gov (United States)

    Reeder, J. R.; Allen, D. H.; Bradley, W. L.

    1998-01-01

    Constant ramp strength tests on unidirectional thermoplastic composite specimens oriented in the 90 deg. direction were conducted at constant temperatures ranging from 149 C to 232 C. Ramp rates spanning 5 orders of magnitude were tested so that failures occurred in the range from 0.5 sec. to 24 hrs. (0.5 to 100,000 MPa/sec). Below 204 C, time-temperature superposition held allowing strength at longer times to be estimated from strength tests at shorter times but higher temperatures. The data indicated that a 50% drop in strength might be expected for this material when the test time is increased by 9 orders of magnitude. The shift factors derived from compliance data applied well to the strength results. To explain the link between compliance and strength, a viscoelastic fracture model was investigated. The model, which used compliance as input, was found to fit the strength data only if the critical fracture energy was allowed to vary with temperature reduced stress rate. This variation in the critical parameter severely limits its use in developing a robust time-dependent strength model. The significance of this research is therefore seen as providing both the indication that a more versatile acceleration method for strength can be developed and the evidence that such a method is needed.

  6. 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...

  7. Creep Strength of Discontinuous Fibre Composites

    DEFF Research Database (Denmark)

    Pedersen, Ole Bøcker

    1974-01-01

    relation between stress and strain rate. Expressions for the interface stress, the creep velocity profile adjacent to the fibres and the creep strength of the composite are derived. Previous results for the creep strength, sc = aVfs0 ( \\frac[( Î )\\dot] [( Î )\\dot] 0 )1/nr1 + 1/n c=Vf001n1+1n in which[( Î...... )\\dot] is the composite creep rate,V f is the fibre volume fraction,sgr 0,epsi 0 andn are the constants in the matrix creep law. The creep strength coefficient agr is found to be very weakly dependent onV f and practically independent ofn whenn is greater than about 6....

  8. 25-hydroxyvitamin D status and change in physical performance and strength in older adults : the Health, Aging, and Body Composition Study

    NARCIS (Netherlands)

    Houston, Denise K; Tooze, Janet A; Neiberg, Rebecca H; Hausman, Dorothy B; Johnson, Mary Ann; Cauley, Jane A; Bauer, Doug C; Cawthon, Peggy M; Shea, M Kyla; Schwartz, Gary G; Williamson, Jeff D; Tylavsky, Frances A; Visser, Marjolein; Simonsick, Eleanor M; Harris, Tamara B; Kritchevsky, Stephen B

    2012-01-01

    Low 25-hydroxyvitamin D (25(OH)D) concentrations are common among older adults and are associated with poorer physical performance and strength, but results from longitudinal studies have been inconsistent. The 25(OH)D threshold for physical performance and strength was determined, and both

  9. Chemical composition and strength of dolomite geopolymer composites

    Science.gov (United States)

    Aizat, E. A.; Al Bakri, A. M. M.; Liew, Y. M.; Heah, C. Y.

    2017-09-01

    The chemical composition of dolomite and the compressive strength of dolomite geopolymer composites were studied. The both composites prepared with mechanical mixer manufactured by with rotor speed of 350 rpm and curing in the oven for 24 hours at 80˚C. XRF analysis showThe dolomite raw materials contain fewer amounts of Si and Al but high Ca in its composition. Dolomite geopolymer composites with 20M of NaOH shows greater and optimum compressive strength compared to dolomite geopolymer with other NaOH molarity. This indicated better interaction of dolomite raw material and alkaline activator need high molarity of NaOH in order to increase the reactivity of dolomite.

  10. Body composition: Where and when.

    Science.gov (United States)

    Mazzoccoli, Gianluigi

    2016-08-01

    The in vivo evaluation of body composition is essential in many clinical investigations, in order to accurately describe and monitor the nutritional status of a range of medical conditions and physiological processes, including sick and malnourished patients, pregnant women, breastfeeding women and the elderly, as well as in patients with cancer, osteoporosis and many other diseases. This research area is also important to the field of human nutrition and exercise physiology. Several research investigations have indicated the importance of measuring fat deposition in different body compartments, in order to gain a fuller understanding of the genetic factors that contribute to obesity, obesity-related disorders, such as dyslipidemia, and thereby to a fuller understanding of obesity associated cardio-metabolic disorders, with relevance to the relationship between body composition and energy expenditure. The spatial and temporal dimension, where and when, may influence the physiological relevance and the pathological implications of the fat composition of different body compartments, and, as such, is a new element to be considered when assessing body composition. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Association study of common variants in the sFRP1 gene region and parameters of bone strength and body composition in two independent healthy Caucasian male cohorts

    DEFF Research Database (Denmark)

    Boudin, Eveline; Piters, Elke; Fransen, Erik

    2012-01-01

    has an influence on bone formation. Therefore this study aimed to investigate the effect of common genetic variation on BMD and bone strength in Caucasian men of different ages. Using HapMap we selected 13 tagSNPs which tag most common genetic variation in and around sFRP1 and we genotyped these SNPs...... parameters. Based on the results of the young cohort we selected three SNPs for further analysis in the complete OAS population. To conclude we tried to replicate the results of two SNPs in an independent population of 994 Belgian men. We found a strong association for rs9694405 with BMI as well in both...

  12. The Effect of High-Intensity Interval Training Versus Strength Training to Improve Body Composition in Women With Polycystic Ovary Syndrome - A Randomized Controlled Trial

    OpenAIRE

    Almenning, Ida

    2014-01-01

    Background: Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting 6-20% of reproductive-age women. Women with PCOS tend to accumulate more upper body fat, and the syndrome is often present with abdominal obesity and visceral adiposity which is further associated with metabolic – and cardiovascular complications. Despite well-established benefits of exercise and its recommendation in PCOS management, few randomized controlled trials have evaluated the...

  13. Effects of Whey, Soy or Leucine Supplementation with 12 Weeks of Resistance Training on Strength, Body Composition, and Skeletal Muscle and Adipose Tissue Histological Attributes in College-Aged Males

    Directory of Open Access Journals (Sweden)

    C. Brooks Mobley

    2017-09-01

    Full Text Available We sought to determine the effects of L-leucine (LEU or different protein supplements standardized to LEU (~3.0 g/serving on changes in body composition, strength, and histological attributes in skeletal muscle and adipose tissue. Seventy-five untrained, college-aged males (mean ± standard error of the mean (SE; age = 21 ± 1 years, body mass = 79.2 ± 0.3 kg were randomly assigned to an isocaloric, lipid-, and organoleptically-matched maltodextrin placebo (PLA, n = 15, LEU (n = 14, whey protein concentrate (WPC, n = 17, whey protein hydrolysate (WPH, n = 14, or soy protein concentrate (SPC, n = 15 group. Participants performed whole-body resistance training three days per week for 12 weeks while consuming supplements twice daily. Skeletal muscle and subcutaneous (SQ fat biopsies were obtained at baseline (T1 and ~72 h following the last day of training (T39. Tissue samples were analyzed for changes in type I and II fiber cross sectional area (CSA, non-fiber specific satellite cell count, and SQ adipocyte CSA. On average, all supplement groups including PLA exhibited similar training volumes and experienced statistically similar increases in total body skeletal muscle mass determined by dual X-ray absorptiometry (+2.2 kg; time p = 0.024 and type I and II fiber CSA increases (+394 μm2 and +927 μm2; time p < 0.001 and 0.024, respectively. Notably, all groups reported increasing Calorie intakes ~600–800 kcal/day from T1 to T39 (time p < 0.001, and all groups consumed at least 1.1 g/kg/day of protein at T1 and 1.3 g/kg/day at T39. There was a training, but no supplementation, effect regarding the reduction in SQ adipocyte CSA (−210 μm2; time p = 0.001. Interestingly, satellite cell counts within the WPC (p < 0.05 and WPH (p < 0.05 groups were greater at T39 relative to T1. In summary, LEU or protein supplementation (standardized to LEU content does not provide added benefit in increasing whole-body skeletal muscle mass or strength above PLA

  14. The effects of six weeks of supplementation with multi-ingredient performance supplements and resistance training on anabolic hormones, body composition, strength, and power in resistance-trained men

    Directory of Open Access Journals (Sweden)

    Ormsbee Michael J

    2012-11-01

    Full Text Available Abstract Background Resistance training (RT enhances muscle protein synthesis and hypertrophy while increasing strength and power. Some multi-ingredient performance supplements (MIPS have been shown to augment the physiological improvements associated with RT. The purpose of this study was to investigate the impact of specific pre- and post-workout MIPS on anabolic hormones, body composition, muscle strength, and power in resistance-trained men participating in a periodized RT program. Methods Twenty-four ( mean ± SE; 24.0 ± 0.9 years; 180.5 ± 5.8 cm; 83.7 ± 0.5 kg resistance-trained men completed 6 wks of periodized RT (3x/wk. Participants were assigned to one of two groups based upon maximal voluntary contraction of the quadriceps (Biodex to lean mass (LM ratio. Group 1 (n = 13; MIPS consumed one serving of NO-Shotgun® (whey protein, casein protein, branched-chain amino acids, creatine, beta alanine, and caffeine before each workout and one serving of NO-Synthesize® (whey protein, casein protein, branched-chain amino acids, creatine, and beta alanine; Vital Pharmaceuticals, Inc., Davie, FL immediately after each workout and on non-RT days. Group 2 (n = 11; Placebo; PLA consumed a flavor-matched isocaloric maltodextrin placebo. Serum insulin-like growth factor 1, human growth hormone, testosterone, body composition (DXA, circumferences, 1-repetition maximal strength (1RM of the upper (chest press and lower body (leg press, and anaerobic power (Wingate test were assessed before and after the intervention. Statistical analysis included a 2 × 2 (group x time ANOVA with repeated measures. Tukey LSD post hoc tests were used to examine pairwise differences. Significance was set at p  Results There was a main time effect (p = 0.035 for testosterone to increase, but no differences between groups were observed. There were no differences in the other blood hormones. Group x time interactions were observed for LM

  15. Effects of 28 days of resistance exercise and consuming a commercially available pre-workout supplement, NO-Shotgun®, on body composition, muscle strength and mass, markers of satellite cell activation, and clinical safety markers in males

    Directory of Open Access Journals (Sweden)

    Leutholtz Brian

    2009-08-01

    Full Text Available Abstract Purpose This study determined the effects of 28 days of heavy resistance exercise combined with the nutritional supplement, NO-Shotgun®, on body composition, muscle strength and mass, markers of satellite cell activation, and clinical safety markers. Methods Eighteen non-resistance-trained males participated in a resistance training program (3 × 10-RM 4 times/wk for 28 days while also ingesting 27 g/day of placebo (PL or NO-Shotgun® (NO 30 min prior to exercise. Data were analyzed with separate 2 × 2 ANOVA and t-tests (p Results Total body mass was increased in both groups (p = 0.001, but without any significant increases in total body water (p = 0.77. No significant changes occurred with fat mass (p = 0.62; however fat-free mass did increase with training (p = 0.001, and NO was significantly greater than PL (p = 0.001. Bench press strength for NO was significantly greater than PL (p = 0.003. Myofibrillar protein increased with training (p = 0.001, with NO being significantly greater than PL (p = 0.019. Serum IGF-1 (p = 0.046 and HGF (p = 0.06 were significantly increased with training and for NO HGF was greater than PL (p = 0.002. Muscle phosphorylated c-met was increased with training for both groups (p = 0.019. Total DNA was increased in both groups (p = 0.006, while NO was significantly greater than PL (p = 0.038. For DNA/protein, PL was decreased and NO was not changed (p = 0.014. All of the myogenic regulatory factors were increased with training; however, NO was shown to be significantly greater than PL for Myo-D (p = 0.008 and MRF-4 (p = 0.022. No significant differences were located for any of the whole blood and serum clinical chemistry markers (p > 0.05. Conclusion When combined with heavy resistance training for 28 days, NO-Shotgun® is not associated with any negative side effects, nor does it abnormally impact any of the clinical chemistry markers. Rather, NO-Shotgun® effectively increases muscle strength and mass

  16. Body composition variation following diaphragmatic breathing ...

    African Journals Online (AJOL)

    Body composition variation following diaphragmatic breathing. ... effect of commonly prescribed diaphragmatic breathing training on the body composition ... a non-exercising control (NE) group (n = 22) or diaphragmatic breathing (DB) group.

  17. Evaluation of Impact Strength of Epoxy Based Hybrid Composites Reinforced with E-Glass/Kevlar 49

    OpenAIRE

    Jogi , Subhan Ali; Moazam Baloch , Muhammad; Chandio , Ali ,; Memon , Iftikhar Ahmed; Chandio , Ghulaqm Sarwar

    2017-01-01

    International audience; In hybridization different fibers are stacked layer by layer to produce laminates have specific strength and stiffness and employed in light weight high strength applications. Physically mean fabricated hybrid composites used in aerospace, under water, body armors and armed forces establishment. In present work drop-weight impact response of hybrid composites were investigated by making laminates of hybrid composites. In Hybridization layers of E-glass (roving) and Kev...

  18. Relation between body mass index percentile and muscle strength ...

    African Journals Online (AJOL)

    Relation between body mass index percentile and muscle strength and endurance. ... Egyptian Journal of Medical Human Genetics ... They were divided into three groups according to their body mass index percentile where group (a) is equal to or more than 5% percentile yet less than 85% percentile, group (b) is equal to ...

  19. Whole body vibration improves body mass, flexibility and strength in ...

    African Journals Online (AJOL)

    Objectives. This study aimed to determine the effectiveness of whole body vibration (WBV) training for promoting healthrelated physical fitness in sedentary adults. Design. A non-randomised sampling technique was used with an equivalent match-pair comparison group, pre- and posttest design. Volunteers were gathered ...

  20. Body composition, dietary intake and supplement use among ...

    African Journals Online (AJOL)

    can influence an athlete's speed, endurance and power, whereas body composition can affect an athlete's strength, agility and appear- ance.' 1. Determining ... activity, provide more consistent training sessions, improve recovery of muscle tissue ... per week (swimming, cycling and running) or triathletes who com- pleted an ...

  1. Fitness and body composition profiling of elite junior South African ...

    African Journals Online (AJOL)

    Objective. The aim of this study was to describe the body composition, strength and speed characteristics of elite junior South African rugby players. Design. Cross-sectional. Setting. Field study. Subjects. Rugby players (16 and 18 years old, N = 174) selected for the South African Rugby Union National Green Squad.

  2. Exercise affects body composition but not weight in postmenopausal women.

    NARCIS (Netherlands)

    Velthuis, M.J.; Schuit, A.J.; Peeters, P.H.M.; Monninkhof, E.M.

    2009-01-01

    OBJECTIVE: The aim of this study was to investigate the effect of a 12-month moderate-to-vigorous exercise program combining aerobic and muscle strength training on body composition among sedentary, postmenopausal women. METHODS: A randomized controlled trial was conducted. A total of 189 sedentary

  3. Impact strength on fiber-reinforced hybrid composite

    International Nuclear Information System (INIS)

    Firdaus, S M; Nurdina; Ariff, M Azmil

    2013-01-01

    Acrylonitrile-Butadiene-Styrene (ABS) has been well known composite in automotive players to have light weight with high impact strength material compared to sheet metal material which has high impact strength but heavy in weight. In this project, the impact strength properties of fabricated pure ABS were compared to the eight samples of hybrid ABS composite with different weight percentages of short fibers and particle sizes of ground rubber. The objective was to improve the impact strength in addition of short fibers and ground rubber particles. These samples were then characterized using an un-notched Izod impact test. Results show that the increasing of filler percentage yielded an adverse effect on the impact strength of the hybrid composite. The effect of the ground rubber particulate sizes however are deemed to be marginal than the effect of varying filler percentage based on the collected impact strength data from all physically tested hybrid composites

  4. Development of methods for body composition studies

    International Nuclear Information System (INIS)

    Mattsson, Soeren; Thomas, Brian J

    2006-01-01

    This review is focused on experimental methods for determination of the composition of the human body, its organs and tissues. It summarizes the development and current status of fat determinations from body density, total body water determinations through the dilution technique, whole and partial body potassium measurements for body cell mass estimates, in vivo neutron activation analysis for body protein measurements, dual-energy absorptiometry (DEXA), computed tomography (CT) and magnetic resonance imaging (MRI, fMRI) and spectroscopy (MRS) for body composition studies on tissue and organ levels, as well as single- and multiple-frequency bioimpedance (BIA) and anthropometry as simple easily available methods. Methods for trace element analysis in vivo are also described. Using this wide range of measurement methods, together with gradually improved body composition models, it is now possible to quantify a number of body components and follow their changes in health and disease. (review)

  5. Development of methods for body composition studies

    Energy Technology Data Exchange (ETDEWEB)

    Mattsson, Soeren [Department of Radiation Physics, Lund University, Malmoe University Hospital, SE-205 02 Malmoe (Sweden); Thomas, Brian J [School of Physical and Chemical Sciences, Queensland University of Technology, Brisbane, QLD 4001 (Australia)

    2006-07-07

    This review is focused on experimental methods for determination of the composition of the human body, its organs and tissues. It summarizes the development and current status of fat determinations from body density, total body water determinations through the dilution technique, whole and partial body potassium measurements for body cell mass estimates, in vivo neutron activation analysis for body protein measurements, dual-energy absorptiometry (DEXA), computed tomography (CT) and magnetic resonance imaging (MRI, fMRI) and spectroscopy (MRS) for body composition studies on tissue and organ levels, as well as single- and multiple-frequency bioimpedance (BIA) and anthropometry as simple easily available methods. Methods for trace element analysis in vivo are also described. Using this wide range of measurement methods, together with gradually improved body composition models, it is now possible to quantify a number of body components and follow their changes in health and disease. (review)

  6. Nutritional assessment with body composition measurements

    International Nuclear Information System (INIS)

    Shizgal, H.M.

    1987-01-01

    The measurement of body composition by multiple isotope dilution provides an accurate and precise measure of both the nutritional state and the response to nutritional support. A multiple isotope dilution technique has been developed that permits measurement of the three major components of body composition: body fat, extracellular mass (ECM), and body cell mass (BCM). Normal body composition was defined by data obtained in 25 healthy volunteers. Malnutrition is characterized by a loss of BCM and an expansion of the ECM, and as a result the lean body mass is not significantly different from normal. The loss of body weight with malnutrition therefore often reflects the loss of body fat. The utility of body composition measurements was demonstrated by determining the effect of total parenteral nutrition on body composition to determine the relationship between caloric intake and the change in the BCM. A statistically significant relationship was developed which demonstrated that a caloric intake in the range of 30-40 cal/kg/day is required for maintenance. To restore a depleted or malnourished BCM requires a caloric intake in excess of that required for maintenance. The measurement of body composition by multiple isotope dilution is complex and time consuming, and requires specialized laboratory facilities and specially trained personnel. As a result, these measurements are not suited for routine patient management, but should rather be reserved for research purposes

  7. Review of probabilistic models of the strength of composite materials

    International Nuclear Information System (INIS)

    Sutherland, L.S.; Guedes Soares, C.

    1997-01-01

    The available literature concerning probabilistic models describing the strength of composite materials has been reviewed to highlight the important aspects of this behaviour which will be of interest to the modelling and analysis of a complex system. The success with which these theories have been used to predict experimental results has been discussed. Since the brittle reinforcement phase largely controls the strength of composites, the probabilistic theories used to describe the strength of brittle materials, fibres and bundles of fibres have been detailed. The use of these theories to predict the strength of composite materials has been considered, along with further developments incorporating the damage accumulation observed in the failure of such materials. Probabilistic theories of the strength of short-fibre composites have been outlined. Emphasis has been placed throughout on straightforward engineering explanations of these theories and how they may be used, rather than providing comprehensive statistical descriptions

  8. A Field Test for Upper Body Strength and Endurance.

    Science.gov (United States)

    Nelson, Jack K.; And Others

    1991-01-01

    Researchers studied the reliability of the modified push-up test in measuring upper body strength and endurance in elementary through college students. It also examined the accuracy of partner scoring. The test proved much easier to administer than the regular floor push-up. It was valid and reliable for all students and suitable for partner…

  9. Effective longitudinal strength of high temperature metal-matrix composites

    International Nuclear Information System (INIS)

    Craddock, J.N.; Savvides, I.

    1991-01-01

    Several models for predicting the longitudinal strength of fiber composites are presented, ranging from a simple netting analysis to a model incorporating curvilinear strain hardening for all the components. Results from these models are presented for tungsten fiber reinforced superalloys, FeCrAlY and MARM200. It is shown that a simple elastic limit micromechanical model does not always adequately describe the useful strength of the composites. The methods proposed here are shown to be more appropriate for predicting the effective composite strength. 2 refs

  10. Acute Effects of Partial-Body Cryotherapy on Isometric Strength: Maximum Handgrip Strength Evaluation.

    Science.gov (United States)

    De Nardi, Massimo; Pizzigalli, Luisa; Benis, Roberto; Caffaro, Federica; Micheletti Cremasco, Margherita

    2017-12-01

    De Nardi, M, Pizzigalli, L, Benis, R, Caffaro, F, and Cremasco, MM. Acute effects of partial-body cryotherapy on isometric strength: maximum handgrip strength evaluation. J Strength Cond Res 31(12): 3497-3502, 2017-The aim of the study was to evaluate the influence of a single partial-body cryotherapy (PBC) session on the maximum handgrip strength (JAMAR Hydraulic Hand dynamometer). Two hundred healthy adults were randomized into a PBC group and a control group (50 men and 50 women in each group). After the initial handgrip strength test (T0), the experimental group performed a 150-second session of PBC (temperature range between -130 and -160° C), whereas the control group stayed in a thermo neutral room (22.0 ± 0.5° C). Immediately after, both groups performed another handgrip strength test (T1). Data underlined that both groups showed an increase in handgrip strength values, especially the experimental group (Control: T0 = 39.48 kg, T1 = 40.01 kg; PBC: T0 = 39.61 kg, T1 = 41.34 kg). The analysis also reported a statistical effect related to gender (F = 491.99, P ≤ 0.05), with women showing lower handgrip strength values compared with men (women = 30.43 kg, men = 52.27 kg). Findings provide the first evidence that a single session of PBC leads to the improvement of muscle strength in healthy people. The results of the study imply that PBC could be performed also before a training session or a sport competition, to increase hand isometric strength.

  11. Effect of surface treatments on the bond strengths of facing composite resins to zirconia copings.

    Science.gov (United States)

    Tsumita, M; Kokubo, Y; Kano, T

    2012-09-01

    The present study evaluated and compared the bond strength between zirconia and facing composite resin using different surface conditioning methods before and after thermocycling. Four primers, three opaque resins, and two facing composite resins were used, and 10 surface treatment procedures were conducted. The bond strength was measured before and after 4,000 cycles of thermocycling. The mean values of each group were statistically analyzed using one-way analysis of variance (ANOVA). The bond strengths of facing composite resins to zirconia after various treatments varied depending on the primers, opaque resins, body resins, and thermocycling. The application of primers and opaque resins to the zirconia surface after sandblasting is expected to yield strong bond strength of the facing composite resin (Estenia CG&B) even after thermocycling.

  12. SWCNT Composites, Interfacial Strength and Mechanical Properties

    DEFF Research Database (Denmark)

    Ma, Jing; Larsen, Mikael

    2013-01-01

    Abstract: Single-Walled Carbon Nanotubes (SWCNT) have despite the superior mechanical properties not fully lived up to the promise as reinforcement in SWCNT composites. The strain transfer from matrix to carbon nanotubes (CNT) is poorly understood and is caused by both fewer localized strong...... is applied to the composite materials. The effect of polymer matrix, modification and concentration of the CNTs are discussed. The strain transfer i.e. 2D band shift under tension is compared to the mechanical properties of the SWCNT composite material....

  13. Feasibility of protein-sparing modified fast by tube (ProMoFasT) in obesity treatment: a phase II pilot trial on clinical safety and efficacy (appetite control, body composition, muscular strength, metabolic pattern, pulmonary function test).

    Science.gov (United States)

    Sukkar, S G; Signori, A; Borrini, C; Barisione, G; Ivaldi, C; Romeo, C; Gradaschi, R; Machello, N; Nanetti, E; Vaccaro, A L

    2013-01-01

    Anecdotal data in the last few years suggest that protein-sparing modified diet (PSMF) delivered by naso-gastric tube enteral (with continuous feeding) could attain an significant weight loss and control of appetite oral feeding, but no phase II studies on safety and efficacy have been done up to now. To verify the safety and efficacy of a protein-sparing modified fast administered by naso-gastric tube (ProMoFasT) for 10 days followed by 20 days of a low-calorie diet, in patients with morbid obesity (appetite control, fat free mass maintenance, pulmonary function tests and metabolic pattern, side effects), 26 patients with a BMI ≥30 kg/m 2 have been selected. The patients had to follow a protein-sparing fast by enteral nutrition (ProMoFasT) for 24 h/day, for 10 days followed by 20 days of low-calorie diet (LCD). The endpoint was represented by body weight, BMI, abdominal circumference, Haber's appetite test, body composition by body impedance assessment (BIA), handgrip strength test, metabolic pattern, pulmonary function test. Safety was assessed by evaluation of complications and side effects of PSMF and/or enteral nutrition. In this report the results on safety and efficacy are described after 10 and 30 days of treatment. After the recruiting phase, a total of 22 patients out of 26 enrolled [14 (63.6 %) females] were evaluated in this study. Globally almost all clinical parameters changed significantly during first 10 days. Total body weight significantly decreased after 10 days (∆-6.1 ± 2; p  < 0.001) and this decrease is maintained in the following 20 days of LCD (∆ = -5.88 ± 1.79; p  < 0.001). Also the abdominal circumference significantly decreased after 10 days [median (range): -4.5 (-30 to 0); p  < 0.001] maintained then in the following 20 days of LCD [median (range) = -7 (-23.5 to -2); p  < 0.001]. All BIA parameters significantly changed after 10 and 30 days from baseline. All parameters except BF had a significant

  14. Association Study of Polymorphisms in the SOST Gene Region and Parameters of Bone Strength and Body Composition in Both Young and Elderly Men: Data from the Odense Androgen Study

    DEFF Research Database (Denmark)

    Piters, Elke; de Freitas, Fenna; Nielsen, Torben Leo

    2011-01-01

    By means of different genetic association studies the SOST gene, encoding sclerostin, has repeatedly been suggested to regulate bone mineral density (BMD) and osteoporosis susceptibility. This study aimed at a further understanding of the importance of two previously studied single...... at several sites and additionally for body composition and hip geometric parameters. In a combined analysis of the young and the elderly OAS, no associations were found for SRP3 either with BMD or with hip geometry. Instead, we found that this polymorphism had a relatively large effect on weight (-1.149 kg...... effect of the minor allele (C). No age-specific effects were found for either of the two SNPs. In summary, we are the first to find interesting associations between SRP3 and body composition. For SRP9, we replicated a site-specific association with femoral neck BMD. In addition, we report a novel...

  15. EFFECTS OF PHYSICAL ACTIVITY ON BODY COMPOSITION IN ADULT WOMEN

    Directory of Open Access Journals (Sweden)

    Klára NAGY

    2017-06-01

    Full Text Available Data published by the World Health Organization (WHO and the International Association for the Study of Obesity (IASO suggests that the number of obese people in Europe has tripled in the last 20 years and resulted in a prevalence of 130 million obese and 400 million people overweight (Sassi et al., 2009.Body composition is the relative percentage of fat and fat-free mass (bones, muscles, organs, water, blood of total body weight. After Wilmore, Buskirk, DiGirolamo and Lohman (1986 the optimal level for health of body fat is 16-25% (18-30% for women.The objective of our study was to assess body composition of adult women, identifying the effect of intervention program on body fat and lean mass, and uncover cases of obesity and overweight.The study involved 95 adult women from Fit4U Fitness Center in Oradea. Period of the study: February 2015 -June 2016. Anthropometric measurements were made: height, weight, circumference, subcutaneous folds. It was calculated the body mass index (BMI, body composition and optimal body weight (estimation based on the five skinfolds measures. The physical activity program consisted of Step -aerobics, Pilates and strength training in the gym, 3 times a week for 60-90 minutes, for 12 months.Results:mean body mass, BMI, BF%, real BF decreased significantly. Mean body fat percentage from 25,63% (± 6,53 decreased to 22,95% (± 5,56. In the studied group overweight and obesity is more frequent in the age group between 35-44 years, but it can be seen the prevalence in all age groups.Conclusions:the physical activity program had a beneficial effect on body composition -by reducing body fat.We found cases of overweight and obesity (21% of the study group.

  16. Body composition of children with cancer.

    Science.gov (United States)

    Murphy, Alexia J; White, Melinda; Davies, Peter S W

    2010-07-01

    Nutritional status, as represented by body composition, is an important consideration in the treatment of pediatric cancer patients because it is linked to poor outcomes. Little is known about how a child's body composition responds to cancer and treatment. We aimed to compare the body composition of children undergoing treatment of cancer with that of healthy controls and to compare body composition between children with hematologic malignancies and children with solid tumors. This cross-sectional study measured height, weight, body cell mass, fat-free mass, and fat mass in 48 children undergoing treatment of cancer and blood-related disorders and in age-matched healthy controls. Patients with cancer had a significantly lower body cell mass index z score (body cell mass/height raised to the power of 2.5 for females and 3 for males) than did controls (P = 0.0001), and 45% of the patients with cancer were considered malnourished according to body cell mass. Subjects with cancer had a significantly higher percentage of body fat (P = 0.0001) and fat mass (P = 0.0001) than did controls; however, there was no significant difference in fat-free mass (P = 0.09). On the basis of percentage fat, 77% of subjects with cancer were considered obese. No difference in body composition was observed between cancer types. This study showed that children undergoing treatment of all types of cancer have a significantly lower body cell mass and a significantly higher fat mass than do healthy controls. Nutritional support is suggested for all children undergoing treatment of cancer.

  17. In vitro study of transverse strength of fiber reinforced composites.

    Science.gov (United States)

    Mosharraf, R; Hashemi, Z; Torkan, S

    2011-01-01

    Reinforcement with fiber is an effective method for considerable improvement in flexural properties of indirect composite resin restorations. The aim of this in-vitro study was to compare the transverse strength of composite resin bars reinforced with pre-impregnated and non-impregnated fibers. Thirty six bar type composite resin specimens (3×2×25 mm) were constructed in three groups. The first group was the control group (C) without any fiber reinforcement. The specimens in the second group (P) were reinforced with pre-impregnated fibers and the third group (N) with non-impregnated fibers. These specimens were tested by the three-point bending method to measure primary transverse strength. Data were statistically analyzed with one way ANOVA and Tukey's tests. There was a significant difference among the mean primary transverse strength in the three groups (Ptransverse strength (Pstudy, it was concluded that reinforcement with fiber considerably increased the transverse strength of composite resin specimens, but impregnation of the fiber used implemented no significant difference in the transverse strength of composite resin samples.

  18. Effect of Cement Composition in Lampung on Concrete Strength

    OpenAIRE

    Riyanto, Hery

    2014-01-01

    The strength and durability of concrete depends on the composition of its constituent materials ie fine aggregate, coarse aggregate, cement, water and other additives. The cement composition is about 10% acting as a binder paste material fine and coarse aggregates. In the Lampung market there are several brands of portland cement used by the community to make concrete construction. Although there is a standard of the government of portland cement composition, yet each brand of cement has diff...

  19. Effect of composite warming on shear bond strength.

    Science.gov (United States)

    McDaniel, Thomas F; Sigrist, Thomas W; Johnson, Gary M

    2018-01-01

    Several manufacturers produce devices designed to warm composite resins used in restorative dentistry. Previous investigators have examined the effects of heating composite restorative resins prior to placement and polymerization. Heating has been reported to reduce viscosity, improve ease of placement, enhance monomer conversion, and reduce microleakage. The aim of the present study was to compare shear bond strengths of room temperature (22°C) and prewarmed (54°C) restorative composite resin. Extracted bovine mandibular incisors were sectioned sagittally and embedded in acrylic cylinders. Enamel was selectively etched with 37% phosphoric acid, rinsed, and dried. Self-etching primer was applied to both enamel and dentin. Self-etching adhesive was then applied and photopolymerized. Composite resin capsules were then divided into prewarmed and room temperature groups. Fourteen composite specimens prewarmed in an incubator were applied to the prepared enamel and dentin and photopolymerized. Fourteen room temperature composite specimens were likewise placed. After storage in water for 24 hours, all composite specimens were subjected to shear stress testing. The resulting data were analyzed with a t test (P = 0.05). There was no statistically significant difference between the shear bond strengths of the prewarmed and room temperature composite resin specimens. Warming does not appear to affect bond strength of composite resin bonded to both dentin and enamel.

  20. Effect of Body Composition on Walking Economy

    Directory of Open Access Journals (Sweden)

    Maciejczyk Marcin

    2016-12-01

    Full Text Available Purpose. The aim of the study was to evaluate walking economy and physiological responses at two walking speeds in males with similar absolute body mass but different body composition. Methods. The study involved 22 young men with similar absolute body mass, BMI, aerobic performance, calf and thigh circumference. The participants differed in body composition: body fat (HBF group and lean body mass (HLBM group. In the graded test, maximal oxygen uptake (VO2max and maximal heart rate were measured. Walking economy was evaluated during two walks performed at two different speeds (4.8 and 6.0 km ‧ h-1. Results. The VO2max was similar in both groups, as were the physiological responses during slow walking. The absolute oxygen uptake or oxygen uptake relative to body mass did not significantly differentiate the studied groups. The only indicator significantly differentiating the two groups was oxygen uptake relative to LBM. Conclusions. Body composition does not significantly affect walking economy at low speed, while during brisk walking, the economy is better in the HLBM vs. HBF group, provided that walking economy is presented as oxygen uptake relative to LBM. For this reason, we recommend this manner of oxygen uptake normalization in the evaluation of walking economy.

  1. OPTIMUM DESIGN OF ULTRAHIGH STRENGTH NANOLAYERED COMPOSITES

    Energy Technology Data Exchange (ETDEWEB)

    H. KUNG; ET AL

    2000-10-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Refinement of the microstructure in metallic multilayers from the micrometer-scale to the nanometer-scale often results in a break down of the classical Hall-Petch model relating strength to the microstructural length scale. The critical length scale at which this behavior breaks down is investigated both experimentally and theoretically. Using transmission electron microscopy and nanoindentation, we evaluated the microstructure and mechanical properties of Cu/Cr, Cu./Ni, and Cu/Nb multilayers that had different shear moduli mismatch between layers and lattice misfit strain between layers. Two-dimensional maps showing layer thickness and grain size ranges over which different deformation mechanisms operate were constructed using dislocation theory. The deformation mechanisms responsible for the breakdown of Hall-Petch behavior are discussed. By correlating the deformation mechanism maps with the experimental data, we show that these maps serve as guidelines for interpreting the scale-dependent deformation mechanisms in multilayers. Atomistic simulation was also used to evaluate the interaction between interfaces and glide dislocations to provide atomic scale insights into the deformation mechanisms.

  2. Longitudinal Physical Activity, Body Composition, and Physical Fitness in Preschoolers.

    Science.gov (United States)

    Leppänen, Marja H; Henriksson, Pontus; Delisle Nyström, Christine; Henriksson, Hanna; Ortega, Francisco B; Pomeroy, Jeremy; Ruiz, Jonatan R; Cadenas-Sanchez, Cristina; Löf, Marie

    2017-10-01

    This study aimed to investigate longitudinal associations of objectively measured physical activity (PA) and sedentary behavior (SB) with body composition and physical fitness at a 12-month follow-up in healthy Swedish 4-yr-old children. The data from the population-based MINISTOP trial were collected between 2014 and 2016, and this study included the 138 children who were in the control group. PA and SB were assessed using the wrist-worn ActiGraph (wGT3x-BT) accelerometer during seven 24-h periods and, subsequently, defined as SB, light-intensity PA, moderate-intensity PA, vigorous-intensity PA (VPA), and moderate-to-vigorous PA (MVPA). Body composition was measured using air-displacement plethysmography and physical fitness (cardiorespiratory fitness, lower and upper muscular strength as well as motor fitness) by the PREFIT fitness battery. Linear regression and isotemporal substitution models were applied. Greater VPA and MVPA at the age of 4.5 yr were associated with higher fat-free mass index (FFMI) at 5.5 yr (P fitness, lower body muscular strength, and motor fitness at 12-month follow-up (P = 0.001 to P = 0.031). Substituting 5 min·d of SB, light-intensity PA, or moderate-intensity PA for VPA at the age of 4.5 yr were associated with higher FFMI, and with greater upper and lower muscular strength at 12-month follow-up (P fitness at 12-month follow-up. Our results indicate that promoting high-intensity PA at young ages may have long-term beneficial effects on childhood body composition and physical fitness, in particular muscular strength.

  3. ADHESIVE SYSTEM AFFECTS REPAIR BOND STRENGTH OF RESIN COMPOSITE

    Directory of Open Access Journals (Sweden)

    Özgür IRMAK

    2017-10-01

    Full Text Available Purpose: This study evaluated the effects of different adhesive systems on repair bond strength of aged resin composites. Materials and Methods: Ninety composite discs were built and half of them were subjected to thermal aging. Aged and non-aged specimens were repaired with resin composite using three different adhesive systems; a two-step self-etch adhesive, a two-step total-etch adhesive and a one-step self-etch adhesive; then they were subjected to shear forces. Data were analyzed statistically. Results: Adhesive type and aging significantly affected the repair bond strengths (p<0.0001. No statistical difference was found in aged composite groups repaired with two-step self- etch or two-step total-etch adhesive. One-step self-etch adhesive showed lower bond strength values in aged composite repair (p<0.0001. Conclusion: In the repair of aged resin composite, two-step self-etch and two-step total-etch adhesives exhibited higher shear bond strength values than that of one-step self-etch adhesive.

  4. Shear bond strength of indirect composite material to monolithic zirconia.

    Science.gov (United States)

    Sari, Fatih; Secilmis, Asli; Simsek, Irfan; Ozsevik, Semih

    2016-08-01

    This study aimed to evaluate the effect of surface treatments on bond strength of indirect composite material (Tescera Indirect Composite System) to monolithic zirconia (inCoris TZI). Partially stabilized monolithic zirconia blocks were cut into with 2.0 mm thickness. Sintered zirconia specimens were divided into different surface treatment groups: no treatment (control), sandblasting, glaze layer & hydrofluoric acid application, and sandblasting + glaze layer & hydrofluoric acid application. The indirect composite material was applied to the surface of the monolithic zirconia specimens. Shear bond strength value of each specimen was evaluated after thermocycling. The fractured surface of each specimen was examined with a stereomicroscope and a scanning electron microscope to assess the failure types. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey LSD tests (α=.05). Bond strength was significantly lower in untreated specimens than in sandblasted specimens (Pcomposite material and monolithic zirconia.

  5. Prediction of strength of wood composite materials using ultrasonic

    International Nuclear Information System (INIS)

    Mahmoud, M.K.; Emam, A.

    2005-01-01

    Wood is a biological material integrating a very large variability of its mechanical properties (tensile and compressive), on the two directional longitudinal and transverse Ultrasonic method has been utilized to measure both wood physical and / or wood mechanical properties. The aim of this article is to show the development of ultrasonic technique for quality evaluation of trees, wood material and wood based composites. For quality assessment of these products we discuss the nondestructive evaluation of different factors such as: moisture content, temperature, biological degradation induced by bacterial attack and fungal attack. These techniques were adapted for trees, timber and wood based composites. The present study discusses the prediction of tensile and compressive strength of wood composite materials using ultrasonic testing. Empirical relationships between the tensile properties, compression strength and ultrasonic were proposed. The experimental results indicate the possibility of establishing a relationship between tensile strength and compression values. Moreover, the fractures in tensile and compressive are discussed by photographic

  6. Characterization of Dentine to Assess Bond Strength of Dental Composites

    Directory of Open Access Journals (Sweden)

    Saad Liaqat

    2015-04-01

    Full Text Available This study was performed to develop alternating dentine adhesion models that could help in the evaluation of a self-bonding dental composite. For this purpose dentine from human and ivory was characterized chemically and microscopically before and after acid etching using Raman and SEM. Mechanical properties of dentine were determined using 3 point bend test. Composite bonding to dentine, with and without use of acid pre-treatment and/or the adhesive, were assessed using a shear bond test. Furthermore, micro gap formation after restoration of 3 mm diameter cavities in dentine was assessed by SEM. Initial hydroxyapatite level in ivory was half that in human dentine. Surface hydroxyapatites decreased by approximately half with every 23 s of acid etch. The human dentine strength (56 MPa was approximately double that of ivory, while the modulus was almost comparable to that of ivory. With adhesive use, average shear bond strengths were 30 and 26 MPa with and without acid etching. With no adhesive, average bond strength was 6 MPa for conventional composites. This, however, increased to 14 MPa with a commercial flowable “self–bonding” composite or upon addition of low levels of an acidic monomer to the experimental composite. The acidic monomer additionally reduced micro-gap formation with the experimental composite. Improved bonding and mechanical properties should reduce composite failures due to recurrent caries or fracture respectively.

  7. Impact strength of small icy bodies that experienced multiple collisions

    Science.gov (United States)

    Yasui, Minami; Hayama, Ryo; Arakawa, Masahiko

    2014-05-01

    Frequent collisions are common for small bodies in the Solar System, and the cumulative damage to these bodies is thought to significantly affect their evolution. It is important to study the effects of multiple impacts such as the number of impacts on the impact strength and the ejection velocity of impact fragments. Here we conducted multiple-impact experiments using a polycrystalline water ice target, varying the number of impacts from 1 to 10 times. An ice cylindrical projectile was impacted at 84-502 m s-1 by using a single-stage gas gun in a cold room between -10 and -15 °C. The impact strength of the ice target that experienced a single impact and multiple impacts is expressed by the total energy density applied to the same target, ΣQ, and this value was observed to be 77.6 J kg-1. The number of fine impact fragments at a fragment mass normalized by an initial target mass, m/Mt0 ∼ 10-6, nm, had a good correlation with the single energy density at each shot, Qj, and the relationship was shown to be nm=10·Qj1.31±0.12. We also estimated the cumulative damage of icy bodies as a total energy density accumulated by past impacts, according to the crater scaling laws proposed by Housen et al. (Housen, K.R., Schmidt, R.M., Holsapple, K.A. [1983]. J. Geophys. Res. 88, 2485-2499) of ice and the crater size distributions observed on Phoebe, a saturnian icy satellite. We found that the cumulative damage of Phoebe depended significantly on the impact speed of the impactor that formed the craters on Phoebe; and the cumulative damage was about one-third of the impact strength ΣQ* at 500 m s-1 whereas it was almost zero at 3.2 km s-1.

  8. Effect of Acute Effort on Isometric Strength and Body Balance: Trained vs. Untrained Paradigm.

    Directory of Open Access Journals (Sweden)

    Stanisław Sterkowicz

    Full Text Available Years of training in competitive sports leads to human body adaptation to a specific type of exercise. In judo bouts, maintaining hand grip on an opponent's clothes and postural balance is essential for the effective technical and tactical actions. This study compares changes after maximal anaerobic exercise among judo athletes and untrained subjects regarding 1 maximum isometric handgrip strength (HGSmax and accuracy at the perceived 50% maximum handgrip force (1/2HGSmax and 2 the balance of 13 judo athletes at national (n = 8 and international (n = 5 competitive levels and 19 untrained university students. The groups did not differ in age, body height, and weight. Body mass index (BMI and body composition (JAWON were evaluated. The Wingate Anaerobic Test (WAnT, Monark 875E measured recommended anaerobic capacity indices. Hand grip strength (Takei dynamometer and balance (biplate balance platform were measured before warm-up (T1, before the WAnT test (T2, and after (T3. Parametric or non-parametric tests were performed after verifying the variable distribution assumption. Judoists had higher BMI and fat-free mass index (FFMI than the students. The athletes also showed higher relative total work and relative peak power and lower levels of lactic acid. The difference in judoists between HGSmax at T1 and HGSmax at T3 was statistically significant. Before warm-up (T1, athletes showed higher strength (more divergent from the calculated ½HGSmax value compared to students. Substantial fatigue after the WAnT test significantly deteriorated the body stability indices, which were significantly better in judo athletes at all time points. The findings suggest specific body adaptations in judoists, especially for body composition, anaerobic energy system efficiency, and postural balance. These characteristics could be trained for specifically by judo athletes to meet the time-motion and anaerobic demands of contemporary bouts.

  9. Effect of Acute Effort on Isometric Strength and Body Balance: Trained vs. Untrained Paradigm.

    Science.gov (United States)

    Sterkowicz, Stanisław; Jaworski, Janusz; Lech, Grzegorz; Pałka, Tomasz; Sterkowicz-Przybycień, Katarzyna; Bujas, Przemysław; Pięta, Paweł; Mościński, Zenon

    2016-01-01

    Years of training in competitive sports leads to human body adaptation to a specific type of exercise. In judo bouts, maintaining hand grip on an opponent's clothes and postural balance is essential for the effective technical and tactical actions. This study compares changes after maximal anaerobic exercise among judo athletes and untrained subjects regarding 1) maximum isometric handgrip strength (HGSmax) and accuracy at the perceived 50% maximum handgrip force (1/2HGSmax) and 2) the balance of 13 judo athletes at national (n = 8) and international (n = 5) competitive levels and 19 untrained university students. The groups did not differ in age, body height, and weight. Body mass index (BMI) and body composition (JAWON) were evaluated. The Wingate Anaerobic Test (WAnT, Monark 875E) measured recommended anaerobic capacity indices. Hand grip strength (Takei dynamometer) and balance (biplate balance platform) were measured before warm-up (T1), before the WAnT test (T2), and after (T3). Parametric or non-parametric tests were performed after verifying the variable distribution assumption. Judoists had higher BMI and fat-free mass index (FFMI) than the students. The athletes also showed higher relative total work and relative peak power and lower levels of lactic acid. The difference in judoists between HGSmax at T1 and HGSmax at T3 was statistically significant. Before warm-up (T1), athletes showed higher strength (more divergent from the calculated ½HGSmax value) compared to students. Substantial fatigue after the WAnT test significantly deteriorated the body stability indices, which were significantly better in judo athletes at all time points. The findings suggest specific body adaptations in judoists, especially for body composition, anaerobic energy system efficiency, and postural balance. These characteristics could be trained for specifically by judo athletes to meet the time-motion and anaerobic demands of contemporary bouts.

  10. Tensile strength of woven yarn kenaf fiber reinforced polyester composites

    OpenAIRE

    A.E. Ismail; M.A. Che Abdul Aziz

    2015-01-01

    This paper presents the tensile strength of woven kenaf fiber reinforced polyester composites. The as-received yarn kenaf fiber is weaved and then aligned into specific fiber orientations before it is hardened with polyester resin. The composite plates are shaped according to the standard geometry and uni-axially loaded in order to investigate the tensile responses. Two important parameters are studied such as fiber orientations and number of layers. According to the results, it is shown that...

  11. Body Composition, Neuromuscular Performance, and Mobility: Comparison Between Regularly Exercising and Inactive Older Women.

    Science.gov (United States)

    Rava, Anni; Pihlak, Anu; Ereline, Jaan; Gapeyeva, Helena; Kums, Tatjana; Purge, Priit; Jürimäe, Jaak; Pääsuke, Mati

    2017-01-01

    The purpose of this study was to evaluate the differences in body composition, neuromuscular performance, and mobility in healthy, regularly exercising and inactive older women, and examine the relationship between skeletal muscle indices and mobility. Overall, 32 healthy older women participated. They were divided into groups according to their physical activity history as regularly exercising (n = 22) and inactive (n = 10) women. Body composition, hand grip strength, leg extensor muscle strength, rapid force development, power output, and mobility indices were assessed. Regularly exercising women had lower fat mass and higher values for leg extensor muscle strength and muscle quality, and also for mobility. Leg extensor muscle strength and power output during vertical jumping and appendicular lean mass per unit of body mass were associated with mobility in healthy older women. It was concluded that long-term regular exercising may have beneficial effects on body composition and physical function in older women.

  12. Estimation of body composition of pigs

    International Nuclear Information System (INIS)

    Ferrell, C.L.; Cornelius, S.G.

    1984-01-01

    A study was conducted to evaluate the use of deuterium oxide (D2O) for in vivo estimation of body composition of diverse types of pigs. Obese (Ob, 30) and contemporary Hampshire X Yorkshire (C, 30) types of pigs used in the study were managed and fed under typical management regimens. Indwelling catheters were placed in a jugular vein of 6 Ob and 6 C pigs at 4, 8, 12, 18 and 24 wk of age. The D2O was infused (.5 g/kg body weight) as a .9% NaCl solution into the jugular catheter. Blood samples were taken immediately before and at .25, 1, 4, 8, 12, 24 and 48 h after the D2O infusion and D2O concentration in blood water was determined. Pigs were subsequently killed by euthanasia injection. Contents of the gastrointestinal tract were removed and the empty body was then frozen and later ground and sampled for subsequent analyses. Ground body tissue samples were analyzed for water, fat, N, fat-free organic matter and ash. Pig type, age and the type X age interaction were significant sources of variation in live weight, D2O pool size and all empty body components, as well as all fat-free empty body components. Relationships between age and live weight or weight of empty body components, and between live weight, empty body weight, empty body water or D2O space and weight of empty components were highly significant but influenced, in most cases, by pig type. The results of this study suggested that, although relationships between D2O space and body component weights were highly significant, they were influenced by pig type and were little better than live weight for the estimation of body composition

  13. Study of Body Composition by Impedance Analysis

    Science.gov (United States)

    González-Solís, J. L.; Vargas-Luna, M.; Sosa-Aquino, M.; Bernal-Alvarado, J.; Gutiérrez-Juárez, G.; Huerta-Franco, R.; Sanchis-Sabater, A.

    2002-08-01

    This work presents a set of impedance measurements and preliminary results on the analysis of body composition using impedance spectroscopy. This study is made using a pork meat sample and spectra from fat and flesh region were independently obtained using the same electrodes array. From these measurements, and theoretical considerations, it is possible to explain the behavior of the composite sample flesh-fat-flesh and, fitting the electrical parameters of the model, it shows the plausibility of a physical and quantitative application to human corporal composition.

  14. The interplay between nutrition and body composition

    African Journals Online (AJOL)

    or radiation treatment for cancer.3.4 The loss of body tissue may be .... adjacent to areas of damage or surgical injury should give valuable .... The composition of weight loss caused by chronic ... pancreatitis (E) (N = 6); burns IF) (N = 4).

  15. Writing Bodies: Somatic Mind in Composition Studies.

    Science.gov (United States)

    Fleckenstein, Kristie S.

    1999-01-01

    Discusses the somatic mind, a permeable materiality in which mind and body resolve into a single entity which is (re)formed by the constantly shifting boundaries of discursive and corporeal intertextualities. Addresses its importance in composition studies. Critiques the poststructuralist disregard of corporeality. (CR)

  16. Bond strength of resin composite to differently conditioned amalgam

    NARCIS (Netherlands)

    Ozcan, M; Vallittu, PK; Huysmans, MC; Kalk, W; Vahlberg, T

    Bulk fracture of teeth, where a part of the amalgam restoration and/or the cusp is fractured, is a common clinical problem. The aim of this study was to evaluate the effect of different surface conditioning methods on the shear bond strength of a hybrid resin composite to fresh amalgam. Amalgams (N

  17. Strength and thermal stability of fiber reinforced plastic composites ...

    African Journals Online (AJOL)

    Therefore, the strength properties and thermal stability of plastic composites reinforced with rattan fibers were investigated in this work. Particles of rattan species (Eremospatha macrocarpa (EM) and Laccosperma secundiflorum (LS)) were blended with High-Density Polyethylene (HDPE) to produce fiber reinforced plastic ...

  18. Effect of simulated pulpal pressure on composite bond strength to ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... Key words: Bond strength, laser treatment, pulpal pressure, resin composite. INTRODUCTION ... bilities for operative and esthetic dentistry (Kato and. Nakabayashi ... E-mail: kimyais@tbzmed.ac.ir. Tel: 0098411- ... pulse repetition rate of 20 pulses per second (20 Hz). ..... Stern RH, Sognnaes RF (1965).

  19. Tensile strength of woven yarn kenaf fiber reinforced polyester composites

    Directory of Open Access Journals (Sweden)

    A.E. Ismail

    2015-12-01

    Full Text Available This paper presents the tensile strength of woven kenaf fiber reinforced polyester composites. The as-received yarn kenaf fiber is weaved and then aligned into specific fiber orientations before it is hardened with polyester resin. The composite plates are shaped according to the standard geometry and uni-axially loaded in order to investigate the tensile responses. Two important parameters are studied such as fiber orientations and number of layers. According to the results, it is shown that fiber orientations greatly affected the ultimate tensile strength but it is not for modulus of elasticity for both types of layers. It is estimated that the reductions of both ultimate tensile strength and Young’s modulus are in the range of 27.7-30.9% and 2.4-3.7% respectively, if the inclined fibers are used with respect to the principal axis.

  20. International society of sports nutrition position stand: diets and body composition

    OpenAIRE

    Aragon, Alan A.; Schoenfeld, Brad J.; Wildman, Robert; Kleiner, Susan; VanDusseldorp, Trisha; Taylor, Lem; Earnest, Conrad P.; Arciero, Paul J.; Wilborn, Colin; Kalman, Douglas S.; Stout, Jeffrey R.; Willoughby, Darryn S.; Campbell, Bill; Arent, Shawn M.; Bannock, Laurent

    2017-01-01

    Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature regarding the effects of diet types (macronutrient composition; eating styles) and their influence on body composition. The ISSN has concluded the following. 1) There is a multitude of diet types and eating styles, whereby numerous subtypes fall under each major dietary archetype. 2) All body composition assessment methods have strengths and limi...

  1. Muscle fibre type composition and body composition in hammer throwers.

    Science.gov (United States)

    Terzis, Gerasimos; Spengos, Konstantinos; Kavouras, Stavros; Manta, Panagiota; Georgiadis, Giorgos

    2010-01-01

    Aim of the present study was to describe the muscle fibre type composition and body composition of well-trained hammer throwers. Six experienced hammer throwers underwent the following measurements: one repetition maximum in squat, snatch, and clean, standing broad jump, backward overhead shot throw and the hammer throw. Dual x-ray absorptiometry was used for body composition analysis. Fibre type composition and cross sectional area was determined in muscle biopsy samples of the right vastus lateralis. Eight physical education students served as a control group. One repetition maximum in squat, snatch and clean for the hammer throwers was 245 ± 21, 132 ± 13 and 165 ± 12kg, respectively. Lean body mass was higher in hammer throwers (85.9 ± 3. 9kg vs. 62.7 ± 5.1kg (p hammer throwers and 51 ± 8% in the control group (p Hammer throwers had significantly larger type IIA fibres (7703 ± 1171 vs. 5676 ± 1270μm(2), p Hammer throwing performance correlated significantly with lean body mass (r = 0.81, p hammer throwers have larger lean body mass and larger muscular areas occupied by type II fibres, compared with relatively untrained subjects. Moreover, it seems that the enlarged muscle mass of the hammer throwers contributes significantly to the hammer throwing performance. Key pointsWell-trained hammer throwers had increased lean body mass, higher type IIA muscle fibres cross sectional areas, as well as higher bone mineral density, compared to controls.Increased lean body mass was closely related with hammer throwing performance.The relative high percentage of type IIX muscle fibres in vastus lateralis in hammer throwers warrants further investigation.

  2. Profiled Deck Composite Slab Strength Verification: A Review

    Directory of Open Access Journals (Sweden)

    K. Mohammed

    2017-12-01

    Full Text Available The purpose of this article is to present an overview on alternate profiled deck composite slab (PDCS strength verification devoid of the expensive and complex laboratory procedures in establishing its longitudinal shear capacity. Despite the several deterministic research findings leading to the development of proposals and modifications on the complex shear characteristics of PDCS that defines its strength behaviour, the laboratory performance testing stands to be the only accurate means for the PDCS strength assessment. The issue is critical and warrants much further thoughts from different perspective other than the deterministic approach that are rather expensive and time consuming. Hence, the development of a rational-based numerical test load function from longitudinal shear capacity consideration is a necessity in augmenting the previous futile attempts for strength determination of PDCS devoid of the costlier and expensive laboratory procedure.

  3. Obesity, body composition, and prostate cancer

    Directory of Open Access Journals (Sweden)

    Fowke Jay H

    2012-01-01

    Full Text Available Abstract Background Established risk factors for prostate cancer have not translated to effective prevention or adjuvant care strategies. Several epidemiologic studies suggest greater body adiposity may be a modifiable risk factor for high-grade (Gleason 7, Gleason 8-10 prostate cancer and prostate cancer mortality. However, BMI only approximates body adiposity, and may be confounded by centralized fat deposition or lean body mass in older men. Our objective was to use bioelectric impedance analysis (BIA to measure body composition and determine the association between prostate cancer and total body fat mass (FM fat-free mass (FFM, and percent body fat (%BF, and which body composition measure mediated the association between BMI or waist circumference (WC with prostate cancer. Methods The study used a multi-centered recruitment protocol targeting men scheduled for prostate biopsy. Men without prostate cancer at biopsy served as controls (n = 1057. Prostate cancer cases were classified as having Gleason 6 (n = 402, Gleason 7 (n = 272, or Gleason 8-10 (n = 135 cancer. BIA and body size measures were ascertained by trained staff prior to diagnosis, and clinical and comorbidity status were determined by chart review. Analyses utilized multivariable linear and logistic regression. Results Body size and composition measures were not significantly associated with low-grade (Gleason 6 prostate cancer. In contrast, BMI, WC, FM, and FFM were associated with an increased risk of Gleason 7 and Gleason 8-10 prostate cancer. Furthermore, BMI and WC were no longer associated with Gleason 8-10 (ORBMI = 1.039 (1.000, 1.081, ORWC = 1.016 (0.999, 1.033, continuous scales with control for total body FFM (ORBMI = 0.998 (0.946, 1.052, ORWC = 0.995 (0.974, 1.017. Furthermore, increasing FFM remained significantly associated with Gleason 7 (ORFFM = 1.030 (1.008, 1.052 and Gleason 8-10 (ORFFM = 1.044 (1.014, 1.074 after controlling for FM. Conclusions Our results

  4. High-strength cellular ceramic composites with 3D microarchitecture.

    Science.gov (United States)

    Bauer, Jens; Hengsbach, Stefan; Tesari, Iwiza; Schwaiger, Ruth; Kraft, Oliver

    2014-02-18

    To enhance the strength-to-weight ratio of a material, one may try to either improve the strength or lower the density, or both. The lightest solid materials have a density in the range of 1,000 kg/m(3); only cellular materials, such as technical foams, can reach considerably lower values. However, compared with corresponding bulk materials, their specific strength generally is significantly lower. Cellular topologies may be divided into bending- and stretching-dominated ones. Technical foams are structured randomly and behave in a bending-dominated way, which is less weight efficient, with respect to strength, than stretching-dominated behavior, such as in regular braced frameworks. Cancellous bone and other natural cellular solids have an optimized architecture. Their basic material is structured hierarchically and consists of nanometer-size elements, providing a benefit from size effects in the material strength. Designing cellular materials with a specific microarchitecture would allow one to exploit the structural advantages of stretching-dominated constructions as well as size-dependent strengthening effects. In this paper, we demonstrate that such materials may be fabricated. Applying 3D laser lithography, we produced and characterized micro-truss and -shell structures made from alumina-polymer composite. Size-dependent strengthening of alumina shells has been observed, particularly when applied with a characteristic thickness below 100 nm. The presented artificial cellular materials reach compressive strengths up to 280 MPa with densities well below 1,000 kg/m(3).

  5. Body composition of term healthy Indian newborns.

    Science.gov (United States)

    Jain, V; Kurpad, A V; Kumar, B; Devi, S; Sreenivas, V; Paul, V K

    2016-04-01

    Previous anthropometry-based studies have suggested that in Indian newborns fat mass is conserved at the expense of lean tissue. This study was undertaken to assess the body composition of Indian newborns and to evaluate its relation with parents' anthropometry, birth weight and early postnatal weight gain. Body composition of healthy term singleton newborns was assessed by the deuterium dilution method in the second week of life. Anthropometry was carried out at birth and on the day of study. Data from 127 babies were analyzed. Birth weight was 2969±383 g. Body composition was assessed at a mean age of 12.7±3.1 days. Fat and fat-free mass were 354±246 and 2764±402 g, respectively, and fat mass percentage (FM%) was 11.3±7.3%. Birth weight and fat-free mass were higher among boys, but no gender difference was noted in FM%. Birth weight was positively correlated with fat as well as fat-free mass but not FM%. FM% showed positive correlation with gain in weight from birth to the day of assessment. This is the first study from India to report body composition in newborns using deuterium dilution. FM% was comparable to that reported for Western populations for babies of similar age. Our results suggest that the percentage of fat and fat-free mass is relatively constant over the range of birth weights included in this study, and greater weight gain during early postnatal period results in greater increase in FM%.

  6. Inorganic Polymer Matrix Composite Strength Related to Interface Condition

    Directory of Open Access Journals (Sweden)

    John Bridge

    2009-12-01

    Full Text Available Resin transfer molding of an inorganic polymer binder was successfully demonstrated in the preparation of ceramic fiber reinforced engine exhaust valves. Unfortunately, in the preliminary processing trials, the resulting composite valves were too brittle for in-engine evaluation. To address this limited toughness, the effectiveness of a modified fiber-matrix interface is investigated through the use of carbon as a model material fiber coating. After sequential heat treatments composites molded from uncoated and carbon coated fibers are compared using room temperature 3-point bend testing. Carbon coated Nextel fiber reinforced geopolymer composites demonstrated a 50% improvement in strength, versus that of the uncoated fiber reinforced composites, after the 250 °C postcure.

  7. Strength analysis of filament-wound composite tubes

    Directory of Open Access Journals (Sweden)

    Vasović Ivana

    2010-01-01

    Full Text Available The subject of this work is focused on strength analysis of filament-wound composite tubes made of E glass/polyester under internal pressure. The primary attention of this investigation is to develop a reliable computation procedure for stress, displacement and initial failure analysis of layered composite tubes. For that purpose we have combined the finite element method (FEM with corresponding initial failure criterions. In addition, finite element analyses using commercial code, MSC/NASTRAN, were performed to predict the behavior of filament wound structures. Computation results are compared with experiments. Good agreement between computation and experimental results are obtained.

  8. Laminated Ti-Al composites: Processing, structure and strength

    DEFF Research Database (Denmark)

    Du, Yan; Fan, Guohua; Yu, Tianbo

    2016-01-01

    Laminated Ti-Al composite sheets with different layer thickness ratios have been fabricated through hot pressing followed by multi-pass hot rolling at 500 °C.The laminated sheets show strong bonding with intermetallic interface layers of nanoscale thickness between the layers of Ti and Al....... The mechanical properties of the composites with different volume fractions of Al from 10% to 67% show a good combination of strength and ductility. A constraint strain in the hot-rolled laminated structure between the hard and soft phases introduces an elastic-plastic deformation stage, which becomes more...

  9. Body composition assessment in American Indian children.

    Science.gov (United States)

    Lohman, T G; Caballero, B; Himes, J H; Hunsberger, S; Reid, R; Stewart, D; Skipper, B

    1999-04-01

    Although the high prevalence of obesity in American Indian children was documented in several surveys that used body mass index (BMI, in kg/m2) as the measure, there is limited information on more direct measurements of body adiposity in this population. The present study evaluated body composition in 81 boys (aged 11.2+/-0.6 y) and 75 girls (aged 11.0+/-0.4 y) attending public schools in 6 American Indian communities: White Mountain Apache, Pima, and Tohono O'Odham in Arizona; Oglala Lakota and Sicangu Lakota in South Dakota; and Navajo in New Mexico and Arizona. These communities were participating in the feasibility phase of Pathways, a multicenter intervention for the primary prevention of obesity. Body composition was estimated by using a combination of skinfold thickness and bioelectrical impedance measurements, with a prediction equation validated previously in this same population. The mean BMI was 20.4+/-4.2 for boys and 21.1+/-5.0 for girls. The sum of the triceps plus subscapular skinfold thicknesses averaged 28.6+/-7.0 mm in boys and 34.0+/-8.0 mm in girls. Mean percentage body fat was 35.6+/-6.9 in boys and 38.8+/-8.5 in girls. The results from this study confirmed the high prevalence of excess body fatness in school-age American Indian children and permitted the development of procedures, training, and quality control for measurement of the main outcome variable in the full-scale Pathways study.

  10. body composition, and subjective assessments of training

    Directory of Open Access Journals (Sweden)

    J Giessing

    2016-08-01

    Full Text Available Most studies of resistance training (RT examine methods that do not resemble typical training practices of persons participating in RT. Ecologically valid RT programs more representative of such practices are seldom compared. This study compared two such approaches to RT. Thirty participants (males, n=13; females, n=17 were randomised to either a group performing low volume ‘High Intensity Training’ (HIT; n=16 or high volume ‘Body-building’ (3ST; n=14 RT methods 2x/week for 10 weeks. Outcomes included muscular performance, body composition, and participant’s subjective assessments. Both HIT and 3ST groups improved muscular performance significantly (as indicated by 95% confidence intervals with large effect sizes (ES; 0.97 to 1.73 and 0.88 to 1.77 respectively. HIT had significantly greater muscular performance gains for 3 of 9 tested exercises compared with 3ST (p < 0.05 and larger effect sizes for 8 of 9 exercises. Body composition did not significantly change in either group. However, effect sizes for whole body muscle mass changes were slightly more favourable in the HIT group compared with the 3ST group (0.27 and -0.34 respectively in addition to whole body fat mass (0.03 and 0.43 respectively and whole body fat percentage (-0.10 and -0.44 respectively. Significant muscular performance gains can be produced using either HIT or 3ST. However, muscular performance gains may be greater when using HIT. Future research should look to identify which components of ecologically valid RT programs are primarily responsible for these differences in outcome.

  11. Repair bond strength of resin composite to bilayer dental ceramics

    Science.gov (United States)

    2018-01-01

    PURPOSE The purpose of this study was to investigate the effect of various surface treatments (ST) on the shear bond strength of resin composite to three bilayer dental ceramics made by CAD/CAM and two veneering ceramics. MATERIALS AND METHODS Three different bilayer dental ceramics and two different veneering ceramics were used (Group A: IPS e.max CAD+IPS e.max Ceram; Group B: IPS e.max ZirCAD+IPS e.max Ceram, Group C: Vita Suprinity+Vita VM11; Group D: IPS e.max Ceram; Group E: Vita VM11). All groups were divided into eight subgroups according to the ST. Then, all test specimens were repaired with a nano hybrid resin composite. Half of the test specimens were subjected to thermocycling procedure and the other half was stored in distilled water at 37℃. Shear bond strength tests for all test specimens were carried out with a universal testing machine. RESULTS There were statistically significant differences among the tested surface treatments within the all tested fracture types (P.00125). CONCLUSION This study revealed that HF etching for glass ceramics and sandblasting for zirconia ceramics were adequate for repair of all ceramic restorations. The effect of ceramic type exposed on the fracture area was not significant on the repair bond strength of resin composites to different ceramic types. PMID:29713430

  12. Volumetric composition and shear strength evaluation of pultruded hybrid kenaf/glass fiber composites

    DEFF Research Database (Denmark)

    Hashemi, Fariborz; Tahir, Paridah Md; Madsen, Bo

    2015-01-01

    by using a gravimetrically based method. Optical microscopy was used to determine the location of voids. The short-beam test method was used to determine the interlaminar shear strength of the composites, and the failure mode was observed. It was found that the void volume fraction of the composites...

  13. Discrepancy between body surface area and body composition in cancer.

    Science.gov (United States)

    Stobäus, Nicole; Küpferling, Susanne; Lorenz, Marie-Luise; Norman, Kristina

    2013-01-01

    Calculation of cytostatic dose is typically based on body surface area (BSA) regardless of body composition. The aim of this study was to assess the discrepancy between BSA and low fat-free mass (FFM) by investigating the prevalence of low FFM with regard to BSA in 630 cancer patients. First, BSA was calculated according to DuBois and DuBois. Patients were divided into 6 categories with respect to their BSA. Each BSA category was further divided into 3 groups according to FFM: low (FFM), normal (-0.99 and 0.99 SD of mean FFM) or high (>1 SD of mean FFM), which was derived through bioelectric impedance analysis. FFM was reduced in 15.7% of patients, 69% had normal and 15.2% had high FFM. In patients with low FFM (i.e., more than-1 SD lower than the mean FFM within their BSA group), body mass index and fatigue were higher whereas functional status was reduced. Moreover, in the subcohort of patients receiving chemotherapy, absolute FFM [Hazard ratio (HR) = 0.970, P = 0.026] as well as the allocation to the low FFM group (HR = 1.644, P = 0.025) emerged as predictors of increased 1-yr mortality. In conclusion, there was a large discrepancy between FFM and BSA. Particularly women were affected by low FFM.

  14. Body composition of italian female hockey players

    Directory of Open Access Journals (Sweden)

    P Pavan

    2009-07-01

    Full Text Available Objective: In this work the anthropometric features and the body composition of Italian hockey players, members of the Female National team, were analysed. The purpose of the research was to verify if morphological features could influence the performance of different positional groups. Materials and Methods: Each player was measured for her total and sitting height, weight, 9 skinfolds thickness and bioelectrical impedance analysis. Different equations were used to calculate the Fat% from skinfolds thickness. Results: Average height is not a crucial advantage for this sport. On the contrary the proportion trunk-limb seems to play an important role for the performance of the midfield players. Percentage of body fat of the hockey players was lower than the Fat% of the non-athletes women of the same age. Significant differences were found between Fat% determined by skinfolds thickness and Fat% obtained by bioelectrical impedance analysis. Conclusions: The results of this study indicate that there are significant differences in anthropometric features and in body composition between positional groups, stressing the importance of a specific training program. Keywords: field hockey, bioelectrical impedance, skinfolds thickness, anthropometry.

  15. Body composition, disordered eating and menstrual regularity in a ...

    African Journals Online (AJOL)

    Body composition, disordered eating and menstrual regularity in a group of South African ... e between body composition and disordered eating in irregular vs normal menstruating athletes. ... measured by air displacement plethysmography.

  16. Immediate repair bond strengths of microhybrid, nanohybrid and nanofilled composites after different surface treatments

    NARCIS (Netherlands)

    Rinastiti, Margareta; Siswomihardjo, Widowati; Busscher, Henk J.; Ozcan, Mutlu

    Objectives: To evaluate immediate repair bond strengths and failure types of resin composites with and without surface conditioning and characterize the interacting composite surfaces by their surface composition and roughness. Methods: Microhybrid, nanohybrid and nanofilled resin composites were

  17. Development of high strength hydroxyapatite for bone tissue regeneration using nanobioactive glass composites

    Science.gov (United States)

    Shrivastava, Pragya; Dalai, Sridhar; Sudera, Prerna; Sivam, Santosh Param; Vijayalakshmi, S.; Sharma, Pratibha

    2013-02-01

    With an increasing demand of biocompatible bone substitutes for the treatment of bone diseases and bone tissue regeneration, bioactive glass composites are being tested to improvise the osteoconductive as well as osteoinductive properties. Nanobioactive glass (nBG) composites, having composition of SiO2 70 mol%, CaO 26 mol % and P2O5 4 mol% were prepared by Freeze drying method using PEG-PPG-PEG co-polymer. Polymer addition improves the mechanical strength and porosity of the scaffold of nBG. Nano Bioactive glass composites upon implantation undergo specific reactions leading to the formation of crystalline hydroxyapatite (HA). This is tested in vitro using Simulated Body Fluid (SBF). This high strength hydroxyapatite (HA) layer acts as osteoconductive in cellular environment, by acting as mineral base of bones, onto which new bone cells proliferate leading to new bone formation. Strength of the nBG composites as well as HA is in the range of cortical and cancellous bone, thus proving significant for bone tissue regeneration substitutes.

  18. Development of high strength hydroxyapatite for bone tissue regeneration using nanobioactive glass composites

    International Nuclear Information System (INIS)

    Shrivastava, Pragya; Dalai, Sridhar; Vijayalakshmi, S.; Sudera, Prerna; Sivam, Santosh Param; Sharma, Pratibha

    2013-01-01

    With an increasing demand of biocompatible bone substitutes for the treatment of bone diseases and bone tissue regeneration, bioactive glass composites are being tested to improvise the osteoconductive as well as osteoinductive properties. Nanobioactive glass (nBG) composites, having composition of SiO 2 70 mol%, CaO 26 mol % and P 2 O 5 4 mol% were prepared by Freeze drying method using PEG-PPG-PEG co-polymer. Polymer addition improves the mechanical strength and porosity of the scaffold of nBG. Nano Bioactive glass composites upon implantation undergo specific reactions leading to the formation of crystalline hydroxyapatite (HA). This is tested in vitro using Simulated Body Fluid (SBF). This high strength hydroxyapatite (HA) layer acts as osteoconductive in cellular environment, by acting as mineral base of bones, onto which new bone cells proliferate leading to new bone formation. Strength of the nBG composites as well as HA is in the range of cortical and cancellous bone, thus proving significant for bone tissue regeneration substitutes.

  19. Effects of chronic acceleration on body composition

    Science.gov (United States)

    Pitts, G. C.

    1982-01-01

    Studies of the centrifugation of adult rats showed an unexpected decrease in the mass of fat-free muscle and bone, in spite of the added load induced by centrifugation. It is suggested that the lower but constant fat-free body mass was probably regulated during centrifugation. Rats placed in weightless conditions for 18.5 days gave indirect but strong evidence that the muscle had increased in mass. Other changes in the rats placed in weightless conditions included a smaller fraction of skeletal mineral, a smaller fraction of water in the total fat-free body, and a net shift of fluid from skin to viscera. Adult rats centrifuged throughout the post-weaning growth period exhibited smaller masses of bone and central nervous system (probably attributable to slower growth of the total body), and a larger mass of skin than controls at 1 G. Efforts at simulating the effects of weightlessness or centrifugation on the body composition of rats by regimens at terrestrial gravity were inconclusive.

  20. The Body and the Beautiful: Health, Attractiveness and Body Composition in Men's and Women's Bodies.

    Directory of Open Access Journals (Sweden)

    Mary-Ellen Brierley

    Full Text Available The dominant evolutionary theory of physical attraction posits that attractiveness reflects physiological health, and attraction is a mechanism for identifying a healthy mate. Previous studies have found that perceptions of the healthiest body mass index (weight scaled for height; BMI for women are close to healthy BMI guidelines, while the most attractive BMI is significantly lower, possibly pointing to an influence of sociocultural factors in determining attractive BMI. However, less is known about ideal body size for men. Further, research has not addressed the role of body fat and muscle, which have distinct relationships with health and are conflated in BMI, in determining perceived health and attractiveness. Here, we hypothesised that, if attractiveness reflects physiological health, the most attractive and healthy appearing body composition should be in line with physiologically healthy body composition. Thirty female and 33 male observers were instructed to manipulate 15 female and 15 male body images in terms of their fat and muscle to optimise perceived health and, separately, attractiveness. Observers were unaware that they were manipulating the muscle and fat content of bodies. The most attractive apparent fat mass for female bodies was significantly lower than the healthiest appearing fat mass (and was lower than the physiologically healthy range, with no significant difference for muscle mass. The optimal fat and muscle mass for men's bodies was in line with the healthy range. Male observers preferred a significantly lower overall male body mass than did female observers. While the body fat and muscle associated with healthy and attractive appearance is broadly in line with physiologically healthy values, deviations from this pattern suggest that future research should examine a possible role for internalization of body ideals in influencing perceptions of attractive body composition, particularly in women.

  1. The Body and the Beautiful: Health, Attractiveness and Body Composition in Men's and Women's Bodies.

    Science.gov (United States)

    Brierley, Mary-Ellen; Brooks, Kevin R; Mond, Jonathan; Stevenson, Richard J; Stephen, Ian D

    2016-01-01

    The dominant evolutionary theory of physical attraction posits that attractiveness reflects physiological health, and attraction is a mechanism for identifying a healthy mate. Previous studies have found that perceptions of the healthiest body mass index (weight scaled for height; BMI) for women are close to healthy BMI guidelines, while the most attractive BMI is significantly lower, possibly pointing to an influence of sociocultural factors in determining attractive BMI. However, less is known about ideal body size for men. Further, research has not addressed the role of body fat and muscle, which have distinct relationships with health and are conflated in BMI, in determining perceived health and attractiveness. Here, we hypothesised that, if attractiveness reflects physiological health, the most attractive and healthy appearing body composition should be in line with physiologically healthy body composition. Thirty female and 33 male observers were instructed to manipulate 15 female and 15 male body images in terms of their fat and muscle to optimise perceived health and, separately, attractiveness. Observers were unaware that they were manipulating the muscle and fat content of bodies. The most attractive apparent fat mass for female bodies was significantly lower than the healthiest appearing fat mass (and was lower than the physiologically healthy range), with no significant difference for muscle mass. The optimal fat and muscle mass for men's bodies was in line with the healthy range. Male observers preferred a significantly lower overall male body mass than did female observers. While the body fat and muscle associated with healthy and attractive appearance is broadly in line with physiologically healthy values, deviations from this pattern suggest that future research should examine a possible role for internalization of body ideals in influencing perceptions of attractive body composition, particularly in women.

  2. Evaluation of Impact Strength of Epoxy Based Hybrid Composites Reinforced with E-Glass/Kevlar 49

    Directory of Open Access Journals (Sweden)

    SUBHAN ALIJOGI

    2017-10-01

    Full Text Available In hybridization different fibers are stacked layer by layer to produce laminates have specific strength and stiffness and employed in light weight high strength applications. Physically mean fabricated hybrid composites used in aerospace, under water, body armors and armed forces establishment. In present work drop-weight impact response of hybrid composites were investigated by making laminates of hybrid composites. In Hybridization layers of E-glass (roving and Kevlar 49 fabrics stacked with epoxy resin. The layers formulation was set up by hand layup method. Impregnationsof epoxy resin of commercial grade (601A in fabrics were accomplished by VRTM (Vacuum Bagging Resin Transfer Molding technique. Layup placementof Glass fibers/ Kevlar at 0°/90°, 45°/45° and 30°/60° were set for this work. Mechanical properties such as impact strength, bear resistance and break resistance were analyzed by usingASTM D-256 and D-3763 standard.Experimental investigation was conducted using instrumented Dart impact and Izod Impact test. E-glass/Kevlar 49 at layup 0°/90°and 30°/60°exhibited improvedimpact strength than 45°/45°. The surface morphology and fractography were also investigated by capturing different images of Specimens by using the SEM (Scanning Electron Microscopy. The fiberreinforcement and matrix fracture were also observed by using SEM.The SEM images suggest that epoxy resin tightly bonded with Kevlar fibers whereas Glass fibers were pulled out from laminations.

  3. Evaluation of impact strength of epoxy based hybrid composites reinforced with e-glass/kevlar 49

    International Nuclear Information System (INIS)

    Jogi, S.A.; Memon, I.A.; Baloch, M.; Chandio, A.D.

    2017-01-01

    In hybridization different fibers are stacked layer by layer to produce laminates have specific strength and stiffness and employed in light weight high strength applications. Physically mean fabricated hybrid composites used in aerospace, under water, body armors and armed forces establishment. In present work drop-weight impact response of hybrid composites were investigated by making laminates of hybrid composites. In Hybridization layers of E-glass (roving) and Kevlar 49 fabrics stacked with epoxy resin. The layers formulation was set up by hand layup method. Impregnations of epoxy resin of commercial grade (601A) in fabrics were accomplished by VRTM (Vacuum Bagging Resin Transfer Molding) technique. Layup placementof Glass fibers/ Kevlar at 0 degree/90 degree, 45 degree/45 degree and 30 degree/60 degree were set for this work. Mechanical properties such as impact strength, bear resistance and break resistance were analyzed by using ASTM D-256 and D-3763 standard. Experimental investigation was conducted using instrumented Dart impact and Izod Impact test. E-glass/Kevlar 49 at layup 0 degree/90 degree and 30 degree/60 degree exhibited improvedimpact strength than 45 degree/45 degree. The surface morphology and fractography were also investigated by capturing different images of Specimens by using the SEM (Scanning Electron Microscopy). The fiberreinforcement and matrix fracture were also observed by using SEM.The SEM images suggest that epoxy resin tightly bonded with Kevlar fibers whereas Glass fibers were pulled out from laminations. (author)

  4. Effect Of RPC Compositions On: Compressive Strength and Absorption

    Directory of Open Access Journals (Sweden)

    Ahmed Sultan Ali

    2016-03-01

    Full Text Available Concrete is a critical material for the construction of infrastructure facilities throughout the world. A new material known as Reactive Powder Concrete (RPC, or sometimes called Ultra-High Performance Concrete (UHPC, is becoming available that differs significantly from traditional concretes. It is an ultra high strength and high ductility composite material with advanced mechanical properties. It consists of special concrete whose microstructure is optimized by precise gradation of all particles in the mix to yield maximum density. Different RPC mixes in the experimental investigation of the present study the mechanical properties of RPC including compressive strength, density and absorption. The main variables used in the production of the different RPC mixes of the present research are three, namely, type of pozzolanic admixture (metakaolin, micro silica, and silica fume, type of fibers (steel and polypropylene fibers and volume fraction of fibers (1.0,1.5, and 2.0%. The experimental results indicated that RPC mixes with silica fume gave the highest values of compressive strength and density and lowest value of absorption in comparison with RPC using micro silica or metakaolin where metakaolin was the third in such comparisons. However the RPC mixes used in the present investigation gave group compressive strength ranging between 164 -195 MPa. It was also found that the use of steel fibers with high volume fraction (2% in an RPC mix increases the compressive strength by 8% and density of the concrete by 2.5% and reduces its absorption by 13%, unlike an RPC mix using polypropylene fibers of lesser volume fraction.

  5. Body composition in remission of childhood cancer

    International Nuclear Information System (INIS)

    Tseytlin, G Ja; Konovalova, M V; Vashura, A Yu; Anisimova, A V; Godina, E Z; Khomyakova, I A; Nikolaev, D V; Starunova, O A; Rudnev, S G

    2012-01-01

    Here, we describe the results of a cross-sectional bioimpedance study of body composition in 552 Russian children and adolescents aged 7-17 years in remission of various types of cancer (remission time 0-15 years, median 4 years). A sample of 1500 apparently healthy individuals of the same age interval was used for comparison. Our data show high frequency of malnutrition in total cancer patients group depending on type of cancer. 52.7% of patients were malnourished according to phase angle and percentage fat mass z-score with the range between 42.2% in children with solid tumors located outside CNS and 76.8% in children with CNS tumors. The body mass index failed to identify the proportion of patients with malnutrition and showed diagnostic sensitivity 50.6% for obesity on the basis of high percentage body fat and even much less so for undernutrition – 13.4% as judged by low phase angle. Our results suggest an advantage of using phase angle as the most sensitive bioimpedance indicator for the assessment of metabolic alterations, associated risks, and the effectiveness of rehabilitation strategies in childhood cancer patients.

  6. Body composition in remission of childhood cancer

    Science.gov (United States)

    Tseytlin, G. Ja; Anisimova, A. V.; Godina, E. Z.; Khomyakova, I. A.; Konovalova, M. V.; Nikolaev, D. V.; Rudnev, S. G.; Starunova, O. A.; Vashura, A. Yu

    2012-12-01

    Here, we describe the results of a cross-sectional bioimpedance study of body composition in 552 Russian children and adolescents aged 7-17 years in remission of various types of cancer (remission time 0-15 years, median 4 years). A sample of 1500 apparently healthy individuals of the same age interval was used for comparison. Our data show high frequency of malnutrition in total cancer patients group depending on type of cancer. 52.7% of patients were malnourished according to phase angle and percentage fat mass z-score with the range between 42.2% in children with solid tumors located outside CNS and 76.8% in children with CNS tumors. The body mass index failed to identify the proportion of patients with malnutrition and showed diagnostic sensitivity 50.6% for obesity on the basis of high percentage body fat and even much less so for undernutrition - 13.4% as judged by low phase angle. Our results suggest an advantage of using phase angle as the most sensitive bioimpedance indicator for the assessment of metabolic alterations, associated risks, and the effectiveness of rehabilitation strategies in childhood cancer patients.

  7. Body Build and the Level of Development of Muscle Strength Among Male Jiu-Jitsu Competitors and Strength-Trained Adults

    Directory of Open Access Journals (Sweden)

    Pietraszewska Jadwiga

    2014-09-01

    Full Text Available Purpose. The aim of the present study was to assess the morpho-functional characteristics of male jiu-jitsu practitioners against a sample of strength-trained university students. Methods. The all-male research sample included 49 jiu-jitsu competitors and 30 university students actively involved in strength training. Measures of body mass and height, lower extremity length, sitting height, arm span, trunk width, skeletal breadths, circumferences and skinfold thicknesses of the trunk and extremities were collected. Body tissue composition was assessed using bioelectrical impedance analysis. Somatotype was classified according to the anthropometric method of Heath and Carter. Participants also performed three motor tests composed of the standing long jump, flexed arm hang, and sit-ups and two dynamometer tests measuring handgrip and back muscle strength. Differences between the measured characteristics in both samples were analyzed using Student’s t test. Pearson’s correlation coefficient was used to the determine the relationships between the morphological characteristics and the results of the motor tests. Results. The jiu-jitsu sample was slightly smaller than the strength-training students. In contrast, body mass was almost identical in both groups. The remaining length, height, and skinfold characteristics also did not differ significantly between the groups. Only hip breadth was significantly larger in the jiu-jitsu sample. No between-group differences were noted in the levels of endomorphy, mesomorphy, and ectomorphy. The composite somatotype of the jiu-jitsu athletes (2.1-5.8-2.0 was very similar to that of the strength-trained students (2.1-5.9-2.4. Statistically significant differences were observed in the tests assessing muscle strength. Handgrip and back muscle strength was greater in the strength-training students, whereas the jiu-jitsu athletes performed better in all three motor tests. Conclusions. The minor morphological

  8. Isolation of aramid nanofibers for high strength multiscale fiber reinforced composites

    Science.gov (United States)

    Lin, Jiajun; Patterson, Brendan A.; Malakooti, Mohammad H.; Sodano, Henry A.

    2018-03-01

    Aramid fibers are famous for their high specific strength and energy absorption properties and have been intensively used for soft body armor and ballistic protection. However, the use of aramid fiber reinforced composites is barely observed in structural applications. Aramid fibers have smooth and inert surfaces that are unable to form robust adhesion to polymeric matrices due to their high crystallinity. Here, a novel method to effectively integrate aramid fibers into composites is developed through utilization of aramid nanofibers. Aramid nanofibers are prepared from macroscale aramid fibers (such as Kevlar®) and isolated through a simple and scalable dissolution method. Prepared aramid nanofibers are dispersible in many polymers due to their improved surface reactivity, meanwhile preserve the conjugated structure and likely the strength of their macroscale counterparts. Simultaneously improved elastic modulus, strength and fracture toughness are observed in aramid nanofiber reinforced epoxy nanocomposites. When integrated in continuous fiber reinforced composites, aramid nanofibers can also enhance interfacial properties by forming hydrogen bonds and π-π coordination to bridge matrix and macroscale fibers. Such multiscale reinforcement by aramid nanofibers and continuous fibers results in strong polymeric composites with robust mechanical properties that are necessary and long desired for structural applications.

  9. Influence of Compositional Variations on Floc Size and Strength

    Science.gov (United States)

    Yin, H.; Tan, X.; Reed, A. H.; Furukawa, Y.; Zhang, G.

    2010-12-01

    Clay-biopolymer micro aggregates or flocs are abundant in waters, including rivers, lakes, and oceans. Owing to their small size and charged surfaces, fine-grained inorganic sediment particles, mainly clays, interact actively with organic substances, such as organic matter and biogenic polymers, to form aggregates or flocs, typically in the size of 10-1000 μm. The flocs in ocean waters are also termed “marine snow”. These flocs are typically porous, tenuous, and soft in nature. During transport in suspension, they may breakdown and decrease in size if the turbulent shear stress exceeds their strength. They may also collide and form larger ones if the shear stress is relatively small. Since flocs of different size and structure settle at different velocities, understanding their strength is also of essential importance for sediment hydrodynamics, transport, and management. Our study focuses on investigating the influence of compositional variations on floc size and strength so that a better understanding of floc dynamics can be achieved. A laser diffraction-based Cilas® particle size and shape analyzer with controllable fluid circulation velocity was employed to conduct floc size measurements and shape imaging, the latter achieved by a high resolution inverted optical microscope, which is also installed with the size analyzer. Totally two clay minerals, kaolinite and illite, were tested as the model inorganic solid skeleton minerals for floc formation, and two biopolymers, anionic xanthan gum and neutral guar gum, were chosen as analogs of naturally occurring organic matter or biopolymers to simulate clay-biopolymer floc formation. Moreover, the concentration of both organic and inorganic phases was varied. The floc breakage or tensile strength was indirectly estimated by the varied fluid flow velocity in the particle size analyzer’s circulation system. For each individual composition, stable flocs were formed by three different fluid circulating velocities

  10. Disease-related malnutrition: influence on body composition and prognosis

    OpenAIRE

    Pirlich, Matthias

    2010-01-01

    Disease-related malnutrition is a frequent clincal problem with severe medical and economic impact. This work summarizes studies on body composition analysis, risk factors, prevalence and prognostic impact of malnutrition. The diagnosis of malnutrition in patients with chronic liver disease is hampered by hyperhydration and requires body composition analysis. Using four different methods for body composition analysis (total body potassium counting, anthropometry, bioelectrical impedance analy...

  11. Comparison of the body compositions in obese and nonobese ...

    African Journals Online (AJOL)

    Total body water, visceral fat accumulation, body mass index, resting metabolic rate, fat‑free mass, bone mass, and muscle mass were significantly higher in obese when compared to those with nonobese (P < 0.001). Thirteen ... Keywords: Body composition, body fat distribution, body mass index, obesity, weight loss ...

  12. Muscle strength and regional lean body mass influence on mineral bone health in young male adults.

    Science.gov (United States)

    Guimarães, Bianca Rosa; Pimenta, Luciana Duarte; Massini, Danilo Alexandre; Dos Santos, Daniel; Siqueira, Leandro Oliveira da Cruz; Simionato, Astor Reis; Dos Santos, Luiz Gustavo Almeida; Neiva, Cassiano Merussi; Pessôa Filho, Dalton Muller

    2018-01-01

    The relationship between muscle strength and bone mineral content (BMC) and bone mineral density (BMD) is supposed from the assumption of the mechanical stress influence on bone tissue metabolism. However, the direct relationship is not well established in younger men, since the enhancement of force able to produce effective changes in bone health, still needs to be further studied. This study aimed to analyze the influence of muscle strength on BMC and BMD in undergraduate students. Thirty six men (24.9 ± 8.6 y/o) were evaluated for regional and whole-body composition by dual energy X-ray absorptiometry (DXA). One repetition maximum tests (1RM) were assessed on flat bench-press (BP), lat-pull down (LPD), leg-curl (LC), knee extension (KE), and leg-press 45° (LP45) exercises. Linear regression modelled the relationships of BMD and BMC to the regional body composition and 1RM values. Measurements of dispersion and error (R2adj and standard error of estimate (SEE)) were tested, setting ρ at ≤0.05. The BMD mean value for whole-body was 1.12±0.09 g/cm2 and BMC attained 2477.9 ± 379.2 g. The regional lean mass (LM) in upper-limbs (UL) (= 6.80±1.21 kg) was related to BMC and BMD for UL (R2adj = 0.74, pBMC and BMD for LL (R2adj = 0.68, pBMC (R2adj = 0.47, pBMC (R2adj = 0.36, pBMC and BMD in young men, strengthening the relationship between force and LM, and suggesting both to parametrizes bone mineral health.

  13. Strength and dynamic characteristics analyses of wound composite axial impeller

    Science.gov (United States)

    Wang, Jifeng; Olortegui-Yume, Jorge; Müller, Norbert

    2012-03-01

    A low cost, light weight, high performance composite material turbomachinery impeller with a uniquely designed blade patterns is analyzed. Such impellers can economically enable refrigeration plants to use water as a refrigerant (R718). A strength and dynamic characteristics analyses procedure is developed to assess the maximum stresses and natural frequencies of these wound composite axial impellers under operating loading conditions. Numerical simulation using FEM for two-dimensional and three-dimensional impellers was investigated. A commercially available software ANSYS is used for the finite element calculations. Analysis is done for different blade geometries and then suggestions are made for optimum design parameters. In order to avoid operating at resonance, which can make impellers suffer a significant reduction in the design life, the designer must calculate the natural frequency and modal shape of the impeller to analyze the dynamic characteristics. The results show that using composite Kevlar fiber/epoxy matrix enables the impeller to run at high tip speed and withstand the stresses, no critical speed will be matched during start-up and shut-down, and that mass imbalances of the impeller shall not pose a critical problem.

  14. Body composition and energy metabolism in elderly people

    NARCIS (Netherlands)

    Visser, M.

    1995-01-01

    This thesis describes several studies related to the three components of energy balance in elderly people: body composition, energy expenditure, and energy intake.

    Body composition. The applicability of the body mass index, skinfold thickness method, and

  15. Strength and failure analysis of composite-to-composite adhesive bonds with different surface treatments

    Science.gov (United States)

    Paranjpe, Nikhil; Alamir, Mohammed; Alonayni, Abdullah; Asmatulu, Eylem; Rahman, Muhammad M.; Asmatulu, Ramazan

    2018-03-01

    Adhesives are widely utilized materials in aviation, automotive, energy, defense, and marine industries. Adhesive joints are gradually supplanting mechanical fasteners because they are lightweight structures, thus making the assembly lighter and easier. They also act as a sealant to prevent a structural joint from galvanic corrosion and leakages. Adhesive bonds provide high joint strength because of the fact that the load is distributed uniformly on the joint surface, while in mechanical joints, the load is concentrated at one point, thus leading to stress at that point and in turn causing joint failures. This research concentrated on the analysis of bond strength and failure loads in adhesive joint of composite-to-composite surfaces. Different durations of plasma along with the detergent cleaning were conducted on the composite surfaces prior to the adhesive applications and curing processes. The joint strength of the composites increased about 34% when the surface was plasma treated for 12 minutes. It is concluded that the combination of different surface preparations, rather than only one type of surface treatment, provides an ideal joint quality for the composites.

  16. Changes in Body Compositions and Basal Metabolic Rates during Treatment of Graves’ Disease

    Directory of Open Access Journals (Sweden)

    Min Joo Kim

    2018-01-01

    Full Text Available Objectives. Because thyroid hormone is an important determinant of body weight and basal metabolic rate, we investigated the changes in the basal metabolic rate and body composition sequentially after treatment for Graves’ disease. Methods. A prospective cohort study was performed with six women newly diagnosed with Graves’ disease. During a 52-week treatment of methimazole, body composition, resting respiratory expenditure (REE, and handgrip strength were measured consecutively. Results. After methimazole treatment, body weight was initially increased (0–8 weeks, subsequently plateaued (8–24 weeks, and gradually decreased in the later period (24–52 weeks despite the decreased food intake. The measured REE was 40% higher than the predicted REE at baseline, and it gradually decreased after treatment. REE positively correlated with thyroid hormone levels, peripheral deiodinase activity, and thyroid’s secretory capacity. Body compositional analyses showed that the fat mass increased during an earlier period (4–12 weeks, while the lean mass increased significantly during the later period (26–52 weeks. Consistent with the lean mass changes, muscle strength also significantly increased during the later period. Conclusions. Treatment of Graves’ disease increased body weight and fat mass transiently with decreased REE. However, long-term compositional changes moved in a beneficial direction increasing lean mass and reinforcing muscle strength, following decreasing fat percentages.

  17. Muscle function and body composition profile in adolescents with restrictive anorexia nervosa: Does resistance training help?

    OpenAIRE

    Fernández del Valle, María; Larumbe Zabala, Eneko; Morandé Lavín, Gonzalo; Pérez Ruiz, Margarita

    2016-01-01

    The aim of this study was to analyze the effects of short-term resistance training on the body composition profile and muscle function in a group of Anorexia Nervosa restricting type (AN-R) patients. The sample consisted of AN-R female adolescents (12.8 ± 0.6 years) allocated into the control and intervention groups (n¼18 each). Body composition and relative strength were assessed at baseline, after 8 weeks and 4 weeks following the intervention. Body mass index (BMI) increased throughout...

  18. Flexural and diametral tensile strength of composite resins

    Directory of Open Access Journals (Sweden)

    Álvaro Della Bona

    2008-03-01

    Full Text Available This study evaluated the flexural strength (sf and the diametral tensile strength (st of light-cured composite resins, testing the hypothesis that there is a positive relation between these properties. Twenty specimens were fabricated for each material (Filtek Z250- 3M-Espe; AM- Amelogen, Ultradent; VE- Vit-l-escence, Ultradent; EX- Esthet-X, Dentsply/Caulk, following ISO 4049 and ANSI/ADA 27 specifications and the manufacturers’ instructions. For the st test, cylindrical shaped (4 mm x 6 mm specimens (n = 10 were placed with their long axes perpendicular to the applied compressive load at a crosshead speed of 1.0 mm/min. The sf was measured using the 3-point bending test, in which bar shaped specimens (n = 10 were tested at a crosshead speed of 0.5 mm/min. Both tests were performed in a universal testing machine (EMIC 2000 recording the fracture load (N. Strength values (MPa were calculated and statistically analyzed by ANOVA and Tukey (a = 0.05. The mean and standard deviation values (MPa were Z250-45.06 ± 5.7; AM-35.61 ± 5.4; VE-34.45 ± 7.8; and EX-42.87 ± 6.6 for st; and Z250-126.52 ± 3.3; AM-87.75 ± 3.8; VE-104.66 ± 4.4; and EX-119.48 ± 2.1 for sf. EX and Z250 showed higher st and sf values than the other materials evaluated (p < 0.05, which followed a decreasing trend of mean values. The results confirmed the study hypothesis, showing a positive relation between the material properties examined.

  19. Exercise program affects body composition but not weight in postmenopausal women

    NARCIS (Netherlands)

    Velthuis, M.J.; Schuit, A.J.; Peeters, P.H.; Monninkhof, E.M.

    2009-01-01

    OBJECTIVE: The aim of this study was to investigate the effect of a 12-month moderate-to-vigorous exercise program combining aerobic and muscle strength training on body composition among sedentary, postmenopausal women. METHODS: A randomized controlled trial was conducted. A total of 189 sedentary

  20. Relation between body mass index percentile and muscle strength ...

    African Journals Online (AJOL)

    Noha Abdel Kader Abdel Kader Hasan

    2016-02-01

    Feb 1, 2016 ... Abstract Background: Muscle strength and endurance in children are very important to develop physical .... the Faculty of Physical Therapy, Cairo university, was used to ..... [9] Noelle G. Quantification of muscle fatigue in cerebral palsy and ... Bouckaert J. Physical fitness and physical activity in obese and.

  1. Correlation between birth weight and maternal body composition.

    LENUS (Irish Health Repository)

    Kent, Etaoin

    2013-01-01

    To estimate which maternal body composition parameters measured using multifrequency segmental bioelectric impedance analysis in the first trimester of pregnancy are predictors of increased birth weight.

  2. Cost-effectiveness, feed utilization and body composition of african ...

    African Journals Online (AJOL)

    Cost-effectiveness, feed utilization and body composition of african sharptooth catfish ( Clarias gariepinus , Burchell 1822) fingerlings fed locally formulated and commercial pelleted diets in tarpaulin tanks.

  3. Body composition and basal metabolic rate in Hidradenitis Suppurativa

    DEFF Research Database (Denmark)

    Miller, I M; Rytgaard, Helene Charlotte; Mogensen, U B

    2016-01-01

    BACKGROUND: Several studies have suggested an association between Hidradenitis Suppurativa (HS) and obesity. Obesity is often expressed as Body Mass Index (BMI). However, BMI lacks information on body composition. General obesity is a predictor of health status and cardiovascular risk, but body...... composition (e.g. abdominal fat) may be more so. Basal metabolic rate (BMR) is an expression of resting metabolism and may serve as a complementary tool when assessing the possibly underlying metabolism behind a persons' body composition. OBJECTIVE: To investigate the body composition and basal metabolic rate...... in individuals with HS compared with healthy controls. METHODS: We performed a cross-sectional study on both a hospital-based and population-based HS group and compared with controls using Bioelectrical Impedance Analysis to assess body composition. RESULTS: We identified a hospital-based HS group of 32 hospital...

  4. Boron enhances strength and alters mineral composition of bone in rabbits fed a high energy diet.

    Science.gov (United States)

    Hakki, Sema S; Dundar, Niyazi; Kayis, Seyit Ali; Hakki, Erdogan E; Hamurcu, Mehmet; Kerimoglu, Ulku; Baspinar, Nuri; Basoglu, Abdullah; Nielsen, Forrest H

    2013-04-01

    An experiment was performed to determine whether boron had a beneficial effect on bone strength and composition in rabbits with apparent adiposity induced by a high energy diet. Sixty female New Zealand rabbits, aged 8 months, were randomly divided into five groups with the following treatments for seven months: control 1, fed alfalfa hay only (5.91 MJ/kg); control 2, high energy diet (11.76 MJ and 3.88 mg boron/kg); B10, high energy diet+10 mg/kg body weight boron gavage/96 h; B30, high energy diet+30 mg/kg body weight boron gavage/96 h; B50, high energy diet+50mg/kg body weight boron gavage/96 h. Bone boron concentrations were lowest in rabbits fed the high energy diet without boron supplementation, which suggested an inferior boron status. Femur maximum breaking force was highest in the B50 rabbits. Tibia compression strength was highest in B30 and B50 rabbits. All boron treatments significantly increased calcium and magnesium concentrations, and the B30 and B50 treatments increased the phosphorus concentration in tibia of rabbits fed the high energy diet. The B30 treatment significantly increased calcium, phosphorus and magnesium concentrations in femur of rabbits fed the high energy diet. Principal component analysis of the tibia minerals showed that the three boron treatments formed a separate cluster from controls. Discriminant analysis suggested that the concentrations of the minerals in femur could predict boron treatment. The findings indicate boron has beneficial effects on bone strength and mineral composition in rabbits fed a high energy diet. Copyright © 2012 Elsevier GmbH. All rights reserved.

  5. Endurance Training Intensity Does Not Mediate Interference to Maximal Lower-Body Strength Gain during Short-Term Concurrent Training.

    Science.gov (United States)

    Fyfe, Jackson J; Bartlett, Jonathan D; Hanson, Erik D; Stepto, Nigel K; Bishop, David J

    2016-01-01

    We determined the effect of concurrent training incorporating either high-intensity interval training (HIT) or moderate-intensity continuous training (MICT) on maximal strength, counter-movement jump (CMJ) performance, and body composition adaptations, compared with single-mode resistance training (RT). Twenty-three recreationally-active males (mean ± SD: age, 29.6 ± 5.5 y; [Formula: see text], 44 ± 11 mL kg -1 ·min -1 ) underwent 8 weeks (3 sessions·wk -1 ) of either: (1) HIT combined with RT (HIT+RT group, n = 8), (2) work-matched MICT combined with RT (MICT+RT group, n = 7), or (3) RT performed alone (RT group, n = 8). Measures of aerobic capacity, maximal (1-RM) strength, CMJ performance and body composition (DXA) were obtained before (PRE), mid-way (MID), and after (POST) training. Maximal (one-repetition maximum [1-RM]) leg press strength was improved from PRE to POST for RT (mean change ± 90% confidence interval; 38.5 ± 8.5%; effect size [ES] ± 90% confidence interval; 1.26 ± 0.24; P body lean mass was similarly increased for RT (4.1 ± 2.0%; ES; 0.33 ± 0.16; P = 0.023) and MICT+RT (3.6 ± 2.4%; ES; 0.45 ± 0.30; P = 0.052); however, this change was attenuated for HIT+RT (1.8 ± 1.6%; ES; 0.13 ± 0.12; P = 0.069). We conclude that concurrent training incorporating either HIT or work-matched MICT similarly attenuates improvements in maximal lower-body strength and indices of CMJ performance compared with RT performed alone. This suggests endurance training intensity is not a critical mediator of interference to maximal strength gain during short-term concurrent training.

  6. Seasonal Changes in Soccer Players' Body Composition and Dietary Intake Practices.

    Science.gov (United States)

    Devlin, Brooke L; Kingsley, Michael; Leveritt, Michael D; Belski, Regina

    2017-12-01

    Devlin, BL, Kingsley, M, Leveritt, MD, and Belski, R. Seasonal changes in soccer players' body composition and dietary intake practices. J Strength Cond Res 31(12): 3319-3326, 2017-The aims of this study were 2-fold: to determine seasonal changes in dietary intake and body composition in elite soccer players and to evaluate the influence of self-determined individual body composition goals on dietary intake and body composition. This longitudinal, observational study assessed body composition (total mass, fat-free soft tissue mass, and fat mass) using dual-energy x-ray absorptiometry and dietary intake (energy and macronutrients) via multiple-pass 24-hour recalls, at 4 time points over a competitive season in elite soccer players from one professional club in the Australian A-League competition. Self-reported body composition goals were also recorded. Eighteen elite male soccer players took part (25 ± 5 years, 180.5 ± 7.4 cm, 75.6 ± 6.5 kg). Majority (≥67%) reported the goal to maintain weight. Fat-free soft tissue mass increased from the start of preseason (55,278 ± 5,475 g) to the start of competitive season (56,784 ± 5,168 g; p nutrition recommendations. The self-reported body composition goals did not strongly influence dietary intake practices or changes in body composition. This study has demonstrated that body composition changes over the course of a soccer season are subtle in elite soccer players despite relatively low self-reported intake of energy and carbohydrate.

  7. Physical function and muscle strength in sporadic inclusion body myositis

    DEFF Research Database (Denmark)

    Jørgensen, Anders N; Aagaard, Per; Nielsen, Jakob L

    2017-01-01

    INTRODUCTION: In this study, self-reported physical function, functional capacity, and isolated muscle function were investigated in sporadic inclusion body myositis (sIBM) patients. METHODS: The 36-item Short Form (SF-36) Health Survey and 2-min walk test (2MWT), timed up & go test (TUG), and 30-s...

  8. Body composition as a frailty marker for the elderly community

    Directory of Open Access Journals (Sweden)

    Falsarella GR

    2015-10-01

    Full Text Available Gláucia Regina Falsarella,1 Lívia Pimenta Renó Gasparotto,1 Caroline Coutinho Barcelos,2 Ibsen Bellini Coimbra,1,2 Maria Clara Moretto,1 Mauro Alexandre Pascoa,3 Talita C B Rezende Ferreira,1 Arlete Maria Valente Coimbra1,41Gerontology Program, Faculty of Medical Sciences, 2Department of Medical Clinics, Faculty of Medical Sciences, 3Department Biodynamics of Movement, Faculty of Physical Education, 4Family Health Program, Gerontology Program, Faculty of Medical Sciences, State University of Campinas (Unicamp, Campinas, São Paulo, BrazilBackground: Body composition (BC in the elderly has been associated with diseases and mortality; however, there is a shortage of data on frailty in the elderly.Objective: To investigate the association between BC and frailty, and identify BC profiles in nonfrail, prefrail, and frail elderly people.Methods: A cross-sectional study comprising 235 elderly (142 females and 93 males aged ≥65 years, from the city of Amparo, State of São Paulo, Brazil, was undertaken. Sociodemographic and cognitive features, comorbidities, medication, frailty, body mass index (BMI, muscle mass, fat mass, bone mass, and fat percent (% data were evaluated. Aiming to examine the relationship between BC and frailty, the Mann–Whitney and Kruskal–Wallis nonparametric tests were applied. The statistical significance level was P<0.05.Results: The nonfrail elderly showed greater muscle mass and greater bone mass compared with the prefrail and frail ones. The frail elderly had greater fat % than the nonfrail elderly. There was a positive association between grip strength and muscle mass with bone mass (P<0.001, and a negative association between grip strength and fat % (P<0.001. Gait speed was positively associated with fat mass (P=0.038 and fat % (P=0.002. The physical activity level was negatively associated with fat % (P=0.022. The weight loss criterion was positively related to muscle mass (P<0.001, bone mass (P=0.009, fat mass

  9. Nutrient Requirements, Body Composition, and Health of Military Women

    National Research Council Canada - National Science Library

    Costello, Rebecca

    1998-01-01

    .... As pan of the Defense Women's Health Research Program, a new report from the Committee on Body Composition, Nutrition, and Health of Military Women of the Institute of the Institute of Medicine examines issues of body composition, fitness, and appearance standards and their impact on the health, nutritional status, and performance of active-duty women.

  10. The effect of Pilates exercise on body composition in sedentary overweight and obese women.

    Science.gov (United States)

    Şavkin, Raziye; Aslan, Ummuhan B

    2017-11-01

    Pilates is a popular exercise approach among women. Still there is poor empirical quantitative evidence indicating a positive effect of Pilates exercises on body composition. The aim of our study is to determine the effects of Pilates exercises on body composition in sedentary overweight and obese women. Thirty-seven women, aged between 30 to 50 (43.79±4.88) years, included the study. Subjects are randomly divided into Pilates group (N.=19) and control group (N.=18). Pilates exercises was given for 90 minutes, 3 times/week, for 8 week with a gradual strength increase of 11-17 in the Rating of Perceived Exercise. Control group did not participate in any physical activity program. Bioelectric Impedance Analysis was used for determine the body composition of participants. Weight, Body Mass Index (BMI), body fat mass, lean body mass, waist, abdomen and hip circumference were measured at pre- and post-training period. In Pilates group, weight, BMI, fat percentage, waist, abdomen and hip circumference decreased significantly after training (P0.05). In control group, abdomen and hip circumference increased significantly (PPilates exercises have positive effects on body composition in sedentary overweight and obese women. Pilates exercises can be applied for improving body composition.

  11. Cylindrical concave body of composite fibrous material

    International Nuclear Information System (INIS)

    1979-01-01

    The invention is concerned with a cylindrical concave body of compound fibrous material which is intended to be exposed to high rotation speeds around its own longitudinal axis. The concave body in question has at least one layer of fibrils that are interwoven and enclose an identical angle with the longitudinal axis of the concave body in both directions. The concave body in question also has at least a second layer of fibrils that run in the direction of the circumference and are fitted radially to the outside. The cylindrical concave body of the invention is particularly well suited for application as a rotor tube in a gas ultra-centrifuge

  12. In vivo body composition studies in malnourished patients

    Energy Technology Data Exchange (ETDEWEB)

    Allen, B J; Blagojevic, N

    1987-09-01

    The establishment of an in vivo TBN facility at Lucas Heights, together with measurement techniques for whole body and extracellular water, is leading to an expanded interest in the relationships between clinical status, body composition and dietary regimes. The ANSTO program provides the opportunity for the first quantitative assessments of these factors in Australia. Body composition studies provide a common link with other-wise unrelated physiological or psychological diseases, and a pool of normal data is being established. Substantial improvements in patient care and quality of life should result from this project, together with a deeper understanding of the importance of body composition in disease-induced malnutrition.

  13. In vivo body composition studies in malnourished patients

    International Nuclear Information System (INIS)

    Allen, B.J.; Blagojevic, N.

    1987-01-01

    The establishment of an in vivo TBN facility at Lucas Heights, together with measurement techniques for whole body and extracellular water, is leading to an expanded interest in the relationships between clinical status, body composition and dietary regimes. The ANSTO program provides the opportunity for the first quantitative assessments of these factors in Australia. Body composition studies provide a common link with other-wise unrelated physiological or psychological diseases, and a pool of normal data is being established. Substantial improvements in patient care and quality of life should result from this project, together with a deeper understanding of the importance of body composition in disease-induced malnutrition

  14. Effect of Sandblasting on Shear Bond Strength Composite Resin Veneer

    Directory of Open Access Journals (Sweden)

    Octarina Octarina

    2013-07-01

    Full Text Available Attachment between restoration and enamel surface in indirect resin composite veneer restoration (IRCV is obtained using multi-step (MS resin cement. Recently, a one step self-adhesive dual-cured resin cement (SADRC was introduced. Objective: To determine the effect of sandblasting on shear bond strength (SBS of IRCV to enamel using MS resin cement and SADRC. Methods: Forty specimens of buccal surface of enamel human were light-cured in Solidilite chamber and were divided into two groups: IRCV without sandblasting (n=20 and with sandblasting for 10 seconds (n=20 and then bonded to enamel using MS (n=10 and SADRC (n=10, respectively. After 24h SBS of specimens were tested using a Universal Testing Machine. Data were analyzed statistically by one-way ANOVA. Results: The average SBS value of IRCV without SB and bonded with MS was 18.95+7.80MPa and MS with SB was 19.30+ SB (4.85+2.12MPa and SADRC with SB (9.57+3.45MPa(p<0.05. Conclusion: increased SBS VIRK to enamel using MS resin cement than SADRC.  

  15. [Evaluation of isometric force in lower limbs and body composition in preterm infants].

    Science.gov (United States)

    Mata Zubillaga, D; Rodríguez Fernández, C; Rodríguez Fernández, L M; de Paz Fernández, J A; Arboleda Franco, S; Alonso Patiño, F

    2015-10-01

    Strength is a physical quality with a clear influence on quality of life. It is determined by the structure of the musculoskeletal system, and depends on the muscular structure. It has been described that prematurity conditions both qualities. The aims of this study are to determine whether prematurity is associated with strength or body composition and evaluate the relationship between prematurity, strength and muscle mass. Case-control study. Participants were premature 7-to-11 year-old children and full-term birth controls. Strength was measured by a strength gauge and body composition from DEXA (duel-energy X-ray absorptiometry) scans. A total of 89 subjects were included and divided into three groups: 30 prematures with birth-weight ≤ 1500g, 29 prematures with birth-weight 1500-2000g, and 30 controls. Weight and BMI z-score was lower in the premature group. No differences were found in muscular mass or strength between groups. A ratio was established between strength and weight or muscular mass. It was observed that it was possible for them to move four times their weight, without finding any differences between groups or a relationship with birth-weight. Between 7 and 11 years of age, children who were premature have lower weight and BMI than the rest of the children. However, there were no differences in body composition or strength between preterm children and controls. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  16. The tensile strength of mechanical joint prototype of lontar fiber composite

    Science.gov (United States)

    Bale, Jefri; Adoe, Dominggus G. H.; Boimau, Kristomus; Sakera, Thomas

    2018-03-01

    In the present study, an experimental activity has been programmed to investigate the effect of joint prototype configuration on tensile strength of lontar (Borassus Flabellifer) fiber composite. To do so, a series of tests were conducted to establish the tensile strength of different joint prototype configuration specimen of lontar fiber composite. In addition, post observation of macroscope was used to map damage behavior. The analysis of lontar fiber composite is a challenge since the material has limited information than others natural fiber composites materials. The results shown that, under static tensile loading, the tensile strength of 13 MPa produced by single lap joint of lontar fiber composite is highest compare to 11 MPa of tensile strength generated by step lap joint and double lap joint where produced the lowest tensile strength of 6 MPa. It is concluded that the differences of tensile strength depend on the geometric dimensions of the cross-sectional area and stress distribution of each joint prototype configuration.

  17. Body composition and dietary intake in neoplasic disease

    International Nuclear Information System (INIS)

    Cohn, S.H.; Gartenhaus, W.; Vartsky, D.; Sawitsky, A.; Zanzi, I.; Vaswani, A.; Yasummure, S.; Rai, K.; Cartes, E.; Ellis, K.J.

    1981-01-01

    Changes in body composition in 37 cancer patients were studied over a period of 6 months. Initially, the patients were divided into two groups: those who lost body weight (over 10%) and those who maintained or gained body weight before the study. Analysis of body composition indicated that patients who lost body weight has caloric and protein intakes markedly below ''normal'' levels at the beginning of the study. There also appears to be a direct relationship between the protein intake and the total body potassium/total body water ratio in the cancer patients. At the end of the 6-month study, the patients were again placed into two groups on the basis of weight loss or gain (and maintenance). Changes in body composition over the period were analyzed in terms of lean body mass, its protein constituent, water, and fat. Weight loss was found to reflect primarily the loss of fat, water, lean body mass (potassium), and only to a minor extent the protein component of lean body mass (nitrogen). Further, on the basis of the values of the ratios of total body nitrogen/total body potassium/total body water, it was possible to ascertain the relative normalcy of the body tissue gained or lost in the 6-month period. The results of the study suggest that the ratio total body nitrogen/total body potassium may serve as the best indicator of recent or ongoing catabolism or anabolism of the neoplastic process. By means of the application of the techniques used for the determination of body composition, it should be possible to assess regimes of hyperalimentation of cancer patients who lose body weight

  18. Thermal degradation and tensile strength of sansevieria trifasciata-polypropylene composites

    Science.gov (United States)

    Abral, H.; Kenedy, E.

    2015-07-01

    The paper exhibits thermal degradation and tensile strength of Sansevieria Trifasciata (ST) fibers and polypropylene (PP) composites. Thermal degradation of ST fibers PP composites was conducted by using thermogravimetry (TGA) instrument, meanwhile tensile strength of the composite was done by using tensile equipment. The results show that the thermal resistance of ST fibers PP composites was higher than that of virgin PP only. Increases in volume fraction of fibers in the composites enhance the tensile strength. Scanning Electron Microscope (SEM) observation exhibits good interface bonding between ST fibers and PP matrix.

  19. Thermal degradation and tensile strength of sansevieria trifasciata-polypropylene composites

    International Nuclear Information System (INIS)

    Abral, H; Kenedy, E

    2015-01-01

    The paper exhibits thermal degradation and tensile strength of Sansevieria Trifasciata (ST) fibers and polypropylene (PP) composites. Thermal degradation of ST fibers PP composites was conducted by using thermogravimetry (TGA) instrument, meanwhile tensile strength of the composite was done by using tensile equipment. The results show that the thermal resistance of ST fibers PP composites was higher than that of virgin PP only. Increases in volume fraction of fibers in the composites enhance the tensile strength. Scanning Electron Microscope (SEM) observation exhibits good interface bonding between ST fibers and PP matrix. (paper)

  20. Body composition in acromegaly - before and after therapy

    International Nuclear Information System (INIS)

    Brummer, R.J.M.; Bengtsson, B.A.; Isaksson, B.

    1986-01-01

    Acromegaly is a disease caused by a benign pituitary tumor producing excess amount of growth hormone. A changed body composition can be a functional parameter of the disorder. The aim of this study is to describe body composition in acromegaly before and after therapy. Total body potassium (TBK) was measured as total exchangeable potassium using 42 K by dilution technique or by counting gamma radiation from the naturally present 40 K in a high sensitivity 3π whole body counter. Total body water (TBW) was determined with an isotope dilution technique using tritiated water as a tracer. The specific activity was measured in urine or plasma. The predicted values for TBK, TBW, and body fat (BF) were calculated by equations using body weight (BW), body height, age and sex as independent variables. The normal values for BW were calculated by using body height and sex as independent variables

  1. Body composition and perception of teenagers from public schools

    Directory of Open Access Journals (Sweden)

    Ana Paula Araújo Ferreira

    2013-10-01

    Full Text Available Adolescence is accompanied by cognitive, emotional, social and biological changes; situations that increase the risk for development of psychosomatic disorders. This study measured and classified body composition and compared it to body self-perception in adolescents. Students from the seventh to ninth grade in public primary education in Distrito Federal, Brazil, answered socio-demographic and body self-perception questionnaires. Weight and height were measured and body mass index (BMI was calculated for body composition classification. From the 977 adolescents, 79.1% presented eutrophic BMI. Of the 473 boys, 11.4% were overweight and 4.7% underweight, 23.8% perceived the body as smaller than it really is and 25.5% tried to gain body mass. Of the 504 girls, 11.9% were overweight and 13.4% underweight, 24.1% perceived the body as larger than it really is and 32.5% tried to lose body mass. Inadequate body composition, prevalent in 20.9% of adolescents, may harm growth, development and health. These problems may be aggravated by the high prevalence of distorted body self-perception and attitudes for bodily changes. It is recommended the implementation of educational interventions on body composition, perception and culture and health, with different approaches by gender.

  2. Differences in body composition and prevalence for postural ...

    African Journals Online (AJOL)

    The aim of this study is to compare the prevalence rate for postural deviations and body composition status among two racial groups in South Africa. The sample (n = 216) consisted of 89 African girls and 127 Caucasian girls. Anthropometric (BMI and percentage body fat) and body posture measurements were performed.

  3. High strength bimetallic composite material fabricated by electroslag casting and characteristics of its composite interface

    Directory of Open Access Journals (Sweden)

    Tian-shun Dong

    2016-11-01

    Full Text Available Bimetallic composite material of bainitic steel and PD3 steel was produced with electroslag casting process, and element distribution of its composite interface was investigated by theoretical calculation and energy dispersive spectrometer (EDS. Results show that the tensile strength (1,450 MPa, hardness (HRC 41-47 and impact toughness (94.7J·cm-2 of bainitic steel were comparatively high, while its elongation was slightly low (4.0%. Tensile strength (1,100 MPa, hardness (>HRC 31 and elongation (7.72% of the interface were also relatively high, but its impact toughness was low at 20.4 J·cm-2. Results of theoretical calculation of the element distribution in the interface region were basically consistent with that of EDS. Therefore, electroslag casting is a practical process to produce bimetallic composite material of bainitic steel and PD3 steel, and theoretical calculation also is a feasible method to study element distribution of their interface.

  4. Body image, nutritional status, abdominal strength, and cardiorespiratory fitness in children and adolescents practicing sports.

    Science.gov (United States)

    Schubert, Alexandre; Januário, Renata Selvatici B; Casonatto, Juliano; Sonoo, Christi Noriko

    2013-01-01

    To verify the association between nutritional status, physical fitness, and body image in children and adolescents. This cross-sectional study included 401 students (236 boys and 165 girls) aged between 8 and 16 years that were regularly enrolled in sports in the local clubs. The nutritional status was evaluated by the body mass index. Students were assessed for satisfaction with body image, abdominal strength resistance, and cardiorespiratory fitness. The variables were assessed on the same day following a standardized order. In order to verify relationships between variables, the chi-square test was used. Afterwards, the binary logistic regression was applied to identify the magnitude of the associations, considering p<0.05 as significant. Association was found between body image and body mass index (p=0.001), abdominal strength resistance (p=0.005) and cardiorespiratory fitness (p=0.001). The Odds Ratio for presenting the body image insatisfaction for those who have not achieved the expected values for the health criteria in abdominal strength resistance and cardiorespiratory fitness were 2.14 and 2.42 times respectively, and for those with overweight and obesity, 2.87 times. Insatisfaction with body image is associated with body mass index and also with physical fitness, abdominal strength resistance, and cardiorespiratory fitness variables.

  5. The effect of titanium surface treatment on the interfacial strength of titanium – Thermoplastic composite joints

    NARCIS (Netherlands)

    Su, Yibo; de Rooij, Matthijn; Grouve, Wouter; Akkerman, Remko

    2017-01-01

    Co-consolidated titanium – carbon fibre reinforced thermoplastic composite hybrid joints show potential for application in aerospace structures. The strength of the interface between the titanium and the thermoplastic composite is crucial for the strength of the entire hybrid joint. Application of a

  6. Effects of muscle composition and architecture on specific strength in obese older women.

    Science.gov (United States)

    Rastelli, F; Capodaglio, P; Orgiu, S; Santovito, C; Caramenti, M; Cadioli, M; Falini, A; Rizzo, G; Lafortuna, C L

    2015-10-01

    What is the central question of this study? Do obesity-specific factors affect skeletal muscle performance in older individuals? What is the main finding and its importance? Older obese women have a larger quadriceps femoris size but develop lower tension per unit of skeletal muscle than their normal-weight counterparts. Muscle impairment and excess body mass are very common among older people. Given that the effect of obesity on strength production has scarcely been studied in older individuals, we analysed functional and structural characteristics of quadriceps femoris (QF) in obese (OB) and normal-weight (NW) older women with comparable habitual physical activity. In five OB (body mass index 36.8 ± 1.9 kg m(-2), age 72.4 ± 2.3 years) and six NW well-functioning older women (body mass index 24.3 ± 1.8 kg m(-2), age 72.7 ± 1.9 years), peak knee-extension torque (KET) was measured in isometric (90 deg knee flexion) and isokinetic conditions (240, 180, 120 and 60 deg s(-1)). Mid-thigh QF cross-sectional area (CSA) and muscle tissue fat content (MF%) were determined with magnetic resonance imaging (Dixon sequence). Muscle fascicle length and pennation angle (PA) were assessed with ultrasonography for each muscle belly of the QF (vastus lateralis, vastus intermedius, rectus femoris and vastus intermedius). Despite similar values of KET, CSA was 17.0% larger in OB than in NW women (P Muscle composition and architecture seem to be important determinants of KET/CSA in elderly women. In fact, owing to the effect of obesity overload, OB women have a larger QF size than NW women, but unfavourable muscle composition and architecture. The higher MF% and steeper PA observed in OB women are associated with reduced levels of muscle specific strength. © 2015 The Authors. Experimental Physiology © 2015 The Physiological Society.

  7. Non-invasive techniques for determining musculoskeleton body composition

    International Nuclear Information System (INIS)

    Cohn, S.H.

    1984-01-01

    In vivo neutron activation analysis, combined with gamma spectrometry, has ushered in a new era of clinical diagnosis and evaluation of therapies, as well as investigation into and modelling of body composition in both normal individuals and patients suffering from various diseases and dysfunctions. Body composition studies have provided baseline data on such vital constituents as nitrogen, potassium and calcium. The non-invasive measurement techniques are particularly suitable for study of the musculo-skeletal changes in body composition. Of particular relevance here is the measurement of calcium loss in astronauts during prolonged space flights

  8. Effect of a New Surface Treatment Solution on the Bond Strength of Composite to Enamel

    Science.gov (United States)

    2016-06-01

    Bond Strength of Composite to Enamel " is appropriately acknowledged and, beyond brief excerpts, is with the permission of the copyright owner...Solution on the Bond Strength of Composite to Enamel ABSTRACT Clean & Boost (Apex Dental Materials) is a novel surface treatment solution...designed to be used in place of phosphoric acid to increase the bond strength of self-etch adhesives to enamel and more effectively remove contaminants

  9. [Attitude change toward body image: the role of elaboration on attitude strength].

    Science.gov (United States)

    Gasco, Margarita; Briñol, Pablo; Horcajo, Javier

    2010-02-01

    Attitude change toward body image: The role of elaboration on attitude strength. Attitudes toward body image have been shown to play a central role in the understanding and treating of eating disorders. In the present research, participants' attitudes toward their body image were changed through a persuasive procedure involving high mental elaboration (self-persuasion) or through a less engaging procedure involving less active participation (passive exposure). As expected, participants in these two groups showed more favourable attitudes toward their bodies than those in the control group. Despite that both treatments were equally efficient in changing attitudes, the strength associated with those attitudes was significantly different depending on the amount of thinking involved in the process of change. Specifically, attitudes were stronger in the high rather than low thinking group of treatment. This finding is important because the strength of the attitude may determine the long-term consequences of an intervention.

  10. Effect of simulated pulpal pressure on composite bond strength to ...

    African Journals Online (AJOL)

    Statistical significance was determined by T-test (p < 0.05). There was a statistically significant difference in the mean microtensile bond strengths between the groups (p < 0.0005). Simulated pulpal pressure had a negative effect on microtensile bond strength of laser ablated dentin when Single Bond adhesive system was ...

  11. High breakdown-strength composites from liquid silicone rubbers

    DEFF Research Database (Denmark)

    Vudayagiri, Sindhu; Zakaria, Shamsul Bin; Yu, Liyun

    2014-01-01

    In this paper we investigate the performance of liquid silicone rubbers (LSRs) as dielectric elastomer transducers. Commonly used silicones in this application include room-temperature vulcanisable (RTV) silicone elastomers and composites thereof. Pure LSRs and their composites with commercially...

  12. Face compression yield strength of the copper-Inconel composite specimen

    International Nuclear Information System (INIS)

    Horie, T.

    1987-05-01

    A new equation for the face compression yield strength of copper-Inconel composite material has been derived. Elastic-plastic finite element analyses were also made for composite specimens with various aspect ratios to examine the edge effect of the specimen. According to the results of both the new equation and the analyses, the face compression yield strength of the composite should be decreased by about 25% from the value obtained with Becker's equation

  13. Differences in body composition and occurrence of postural ...

    African Journals Online (AJOL)

    Differences in body composition and occurrence of postural deviations in boys from two ... African Journal for Physical Activity and Health Sciences ... procedures of the International Society for the Advancement of Kinanthropometry (ISAK).

  14. Hybrid filler composition optimization for tensile strength of jute fibre

    Indian Academy of Sciences (India)

    https://www.ias.ac.in/article/fulltext/boms/039/05/1223-1231 ... The developed composite consists of natural jute fibre as reinforcement and unsaturated ... The effect of weight content of bagasse fibre, carbon black and calcium carbonate ... of pultruded jute fibre polymer composite at the optimum composition of hybrid filler.

  15. Growth performance, body measurements, carcass composition and ...

    African Journals Online (AJOL)

    Gizzard percentage was significantly greater in males, and heart percentage was significantly greater in females. Due to their high bodyweight, good FCR, and favourable carcass composition, SM3 Heavy male ducks are more useful as broiler duck than females. Keywords: carcasses, digestive system, growth, Pekin duck, ...

  16. Body composition validation technique using anthropometrics ...

    African Journals Online (AJOL)

    The horizontal bodyweights of the participantsweremeasured inlying positionsusing anadaptation of theGuthri Smith apparatus frame towhich a firmstretcher and two spring balances were attached on a horizontal level position. The heights of the subjects were also taken on supine lying on a firm plinth. The body weight and ...

  17. the foundation of anthropometry and body composition

    African Journals Online (AJOL)

    method, and, in the case of infants and children, growth monitoring is ... should be remembered that that BMI as such is not the determinant of health and disease. ... regressed on BMI, the standard deviation of residuals is considerable: about 3.2kg. ... to be considered here, including short-term (within-day) body weight.

  18. Body composition estimation from selected slices

    DEFF Research Database (Denmark)

    Lacoste Jeanson, Alizé; Dupej, Ján; Villa, Chiara

    2017-01-01

    Background Estimating volumes and masses of total body components is important for the study and treatment monitoring of nutrition and nutrition-related disorders, cancer, joint replacement, energy-expenditure and exercise physiology. While several equations have been offered for estimating total...

  19. Relationships Between Lower-Body Muscle Structure and Lower-Body Strength, Power, and Muscle-Tendon Complex Stiffness.

    Science.gov (United States)

    Secomb, Josh L; Lundgren, Lina E; Farley, Oliver R L; Tran, Tai T; Nimphius, Sophia; Sheppard, Jeremy M

    2015-08-01

    The purpose of this study was to determine whether any relationships were present between lower-body muscle structure and strength and power qualities. Fifteen elite male surfing athletes performed a battery of lower-body strength and power tests, including countermovement jump (CMJ), squat jump (SJ), isometric midthigh pull (IMTP), and had their lower-body muscle structure assessed with ultrasonography. In addition, lower-body muscle-tendon complex (MTC) stiffness and dynamic strength deficit (DSD) ratio were calculated from the CMJ and IMTP. Significant relationships of large to very large strength were observed between the vastus lateralis (VL) thickness of the left (LVL) and right (RVL) leg and peak force (PF) (r = 0.54-0.77, p well as IMTP PF (r = 0.53-0.60, p = 0.02-0.04). Furthermore, large relationships were found between left lateral gastrocnemius (LG) pennation angle and SJ and IMTP PF (r = 0.53, p = 0.04, and r = 0.70, p < 0.01, respectively) and between LG and IMTP relative PF (r = 0.63, p = 0.01). Additionally, large relationships were identified between lower-body MTC stiffness and DSD ratio (r = 0.68, p < 0.01), right (LG) pennation angle (r = 0.51, p = 0.05), CMJ PF (r = 0.60, p = 0.02), and jump height (r = 0.53, p = 0.04). These results indicate that greater VL thickness and increased LG pennation angle are related to improved performance in the CMJ, SJ, and IMTP. Furthermore, these results suggest that lower-body MTC stiffness explains a large amount of variance in determining an athlete's ability to rapidly apply force during a dynamic movement.

  20. Criterion-Related Validity of a Simple Muscle Strength Test to Assess Whole Body Muscle Strength in Chinese Children Aged 10 to 12 Years.

    Science.gov (United States)

    Yin, Liqin; Tang, Changfa; Tao, Xia

    2018-01-01

    To study the criterion-related validity of simple muscle strength test (SMST) indicators and assess whole body muscle strength in Chinese children aged 10 to 12 years old. Two hundred and forty children were equally divided into four groups in different genders and residences. The SMST indicators (hand-grip, knee bent push-up, back muscle strength, sit-up, leg muscle strength, and standing long jump) were tested. We set up the total level of the whole-body muscle strength ( F total ) through testing isokinetic muscle strength of the six joints' flexion and extension movements. Pearson correlation analyses were used to analyze the correlation between the SMST indicators and the F total . (1) Leg muscle strength and back muscle strength demonstrated the highest validity scores. Sit-ups, hand grip, and standing long jump demonstrated the lowest validity scores. (2) Leg muscle strength had the highest validity for males, but back muscle strength had the highest validity for females. Back muscle strength and leg muscle strength can give the highest validity of assessing whole body muscle strength, and also has higher validity in both the urban and rural children. For urban children, but not rural, the knee bent push-up also has a high validity indicator.

  1. Criterion-Related Validity of a Simple Muscle Strength Test to Assess Whole Body Muscle Strength in Chinese Children Aged 10 to 12 Years

    Directory of Open Access Journals (Sweden)

    Liqin Yin

    2018-01-01

    Full Text Available Objective. To study the criterion-related validity of simple muscle strength test (SMST indicators and assess whole body muscle strength in Chinese children aged 10 to 12 years old. Methods. Two hundred and forty children were equally divided into four groups in different genders and residences. The SMST indicators (hand-grip, knee bent push-up, back muscle strength, sit-up, leg muscle strength, and standing long jump were tested. We set up the total level of the whole-body muscle strength (Ftotal through testing isokinetic muscle strength of the six joints’ flexion and extension movements. Pearson correlation analyses were used to analyze the correlation between the SMST indicators and the Ftotal. Results. (1 Leg muscle strength and back muscle strength demonstrated the highest validity scores. Sit-ups, hand grip, and standing long jump demonstrated the lowest validity scores. (2 Leg muscle strength had the highest validity for males, but back muscle strength had the highest validity for females. Conclusions. Back muscle strength and leg muscle strength can give the highest validity of assessing whole body muscle strength, and also has higher validity in both the urban and rural children. For urban children, but not rural, the knee bent push-up also has a high validity indicator.

  2. The Effects of Whole-Body Vibration on the Cross-Transfer of Strength

    Directory of Open Access Journals (Sweden)

    Alicia M. Goodwill

    2012-01-01

    Full Text Available This study investigated whether the use of superimposed whole-body vibration (WBV during cross-education strength training would optimise strength transfer compared to conventional cross-education strength training. Twenty-one healthy, dominant right leg volunteers (21±3 years were allocated to a strength training (ST, m=3, f=4, a strength training with WBV (ST + V, m=3, f=4, or a control group (no training, m=3, f=4. Training groups performed 9 sessions over 3 weeks, involving unilateral squats for the right leg, with or without WBV (35 Hz; 2.5 mm amplitude. All groups underwent dynamic single leg maximum strength testing (1RM and single and paired pulse transcranial magnetic stimulation (TMS prior to and following training. Strength increased in the trained limb for the ST (41%; ES=1.14 and ST + V (55%; ES=1.03 groups, which resulted in a 35% (ES=0.99 strength transfer to the untrained left leg for the ST group and a 52% (ES=0.97 strength transfer to the untrained leg for the ST + V group, when compared to the control group. No differences in strength transfer between training groups were observed (P=0.15. For the untrained leg, no differences in the peak height of recruitment curves or SICI were observed between ST and ST + V groups (P=1.00. Strength training with WBV does not appear to modulate the cross-transfer of strength to a greater magnitude when compared to conventional cross-education strength training.

  3. PHYSIQUE AND BODY COMPOSITION OF GIRLS PRACTISING CONTEMPORARY DANCE

    Directory of Open Access Journals (Sweden)

    Przednowek Karolina H.

    2017-09-01

    Full Text Available Introduction. Physique and body composition are often explored in sport-related research. This is due to the fact that morphological features can be useful for determining a person’s predispositions for practising a given type of physical activity. Dance, as any other sports discipline, has an impact on the physique and motor skills of those who practise it. Most research concerning the physique and body composition of dancers conducted so far has focused on persons practising ballet or competitive ballroom dancing. Investigating these issues in contemporary dancers is a new field of study. The aim of the current study was to examine the physique and body composition of girls aged 14-17 years practising contemporary dance. Material and methods. The study involved 23 girls who trained contemporary dance twice a week for 2 hours. The participants of the study had been training since the age of six. Basic anthropometric measurements were performed. Body composition was analysed based on parameters measured using a Tanita body composition analyser. Conclusions. The analysis found that girls training contemporary dance were characterised by a leptosomatic physique. BMI values in both younger and older contemporary dancers indicated that their weight was normal. Compared to girls who did not practise any particular type of sport, contemporary dancers had a lower weight, a lower body water percentage, and a lower body fat percentage. The dancers were also characterised by a greater circumference of the waist, hips, arm, and chest compared to untrained peers.

  4. Body composition in children with juvenile idiopathic arthritis: effect ...

    African Journals Online (AJOL)

    Introduction: the aim of this study was to evaluate the relationship between macronutrient intake, body composition (lean body mass and fat mass) and bone mineral content in Moroccan children with juvenile idiopathic arthritis (JIA). Methods: a cross-sectional study, conducted between May 2010 and June 2011, covering ...

  5. PHYSICAL PERFORMANCE AND BODY COMPOSITION IN MAINTENANCE HEMODIALYSIS (MHD PATIENTS

    Directory of Open Access Journals (Sweden)

    M Zhang

    2012-06-01

    Conclusions: These findings indicate that adult MHD pts had a higher % body fat. Measures of physical performance were markedly reduced in MHD pts as compared to Normals. Physical performance in MHD, measured especially by 6-MW, correlated negatively with some measures of body composition, particularly with LBMI.

  6. Changes in body composition as a result of chemotherapy

    NARCIS (Netherlands)

    Berg, van den Maaike M.G.A.

    2017-01-01

    Because of the improved survival rate, both short term and long term adverse effects of breast cancer treatment have become increasingly important. Body weight and body composition before, during, and after chemotherapy may influence side effects during treatment and survival. The aims of this

  7. Bodies in Composition: Teaching Writing through Kinesthetic Performance

    Science.gov (United States)

    Butler, Janine

    2017-01-01

    This article calls on composition instructors to reflect consciously on how we can use our bodies kinesthetically to perform multimodal writing processes through gestural, visual, and spatial modes. Teaching writing through kinesthetic performance can show students that our bodies are being constructed via interaction with audiences, akin to the…

  8. Human body composition models and methodology : theory and experiment

    NARCIS (Netherlands)

    Wang, Z.M.

    1997-01-01


    The study of human body composition is a branch of human biology which focuses on the in vivo quantification of body components, the quantitative relationships between components, and the quantitative changes in these components related to various influencing factors.

  9. Proximate composition of Mystus bleekeri in relation to body size ...

    African Journals Online (AJOL)

    Proximate composition of small catfish, Mystus bleekeri, from Nala Daik, Sialkot, Pakistan was investigated and fluctuation in relation to body size and condition factor was carried out. Mean percentages for water, fat, protein and ash contents in the whole wet body weight of wild M. bleekeri were 77.87, 3.26, 15.01 and ...

  10. changes in body composition and other anthropometric measures of ...

    African Journals Online (AJOL)

    This study aimed to investigate the changes in body composition and other anthropometric .... showing a good fit between the values obtained from the equation ..... ideally at 6-monthly intervals, in order to provide useful information to ... training on quality of life in HAART-treated HIV-positive Rwandan subjects with body fat ...

  11. Strength and fracture behavior of aluminide matrix composites with ceramic fibers

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, M.; Suganuma, K.; Niihara, K.

    1999-07-01

    This paper investigates the fracture behavior of FeAl and Ni{sub 3}Al matrix composites with ceramic continuous fibers 8.5--10 {micro}m in diameter. When stress is applied to these composites, multiple-fracture of fibers predominantly occurs before matrix cracking, because the load carried by the fibers reaches their fracture strength. Fragments which remain longer than the critical length can provide significant strengthening through load bearing even though fiber breaking has occurred. The ultimate fracture strength of the composites also depends on stress relaxation by plastic deformation of the matrix at a crack tip in the multiple-fractured fibers. Ductilizing of the matrix by B doping improves the ultimate strength at ambient temperatures in both composites. However, their mechanical properties at elevated temperatures are quite different. In the case of Ni{sub 3}Al matrix composites, embrittlement of the matrix is undesirable for high strength and reliability at 873--973 K.

  12. The chemical composition and compression strengths of refractory ceramics, tested for 3 curing temperatures

    International Nuclear Information System (INIS)

    Wan Khairuddin bin Wan Ali

    1994-01-01

    An investigation was carried out to determine and compile the mechanical strength of a refractory ceramic made of ground fire bricks and refractory fire mortar. Three different compositions were studied for the compression strength and it was found that the composition with 50% fire bricks and 50% fire mortar gives the best mechanical strength. With this composition the maximum failure compression stress is 3.2 MPa. and the Young Modulus is 403.5 MPa. The investigation also shows that the curing temperatures and the composition percentages play an important role in determining the strength of the ceramic. The trend obtained from the investigation shows that there is the possibility that an optimum value of composition percentage exist

  13. Impact of Body Weight and Body Composition on Ovarian Cancer Prognosis.

    Science.gov (United States)

    Purcell, Sarah A; Elliott, Sarah A; Kroenke, Candyce H; Sawyer, Michael B; Prado, Carla M

    2016-02-01

    Measures of body weight and anthropometrics such as body mass index (BMI) are commonly used to assess nutritional status in clinical conditions including cancer. Extensive research has evaluated associations between body weight and prognosis in ovarian cancer patients, yet little is known about the potential impact of body composition (fat mass (FM) and fat-free mass (FFM)) in these patients. Thus, the purpose of this publication was to review the literature (using PubMed and EMBASE) evaluating the impact of body weight and particularly body composition on surgical complications, morbidity, chemotherapy dosing and toxicity (as predictors of prognosis), and survival in ovarian cancer patients. Body weight is rarely associated with intra-operative complications, but obesity predicts higher rates of venous thromboembolism and wound complications post-operatively in ovarian cancer patients. Low levels of FM and FFM are superior predictors of length of hospital stay compared to measures of body weight alone, but the role of body composition on other surgical morbidities is unknown. Obesity complicates chemotherapy dosing due to altered pharmacokinetics, imprecise dosing strategies, and wide variability in FM and FFM. Measurement of body composition has the potential to reduce toxicity if the results are incorporated into chemotherapy dosing calculations. Some findings suggest that excess body weight adversely affects survival, while others find no such association. Limited studies indicate that FM is a better predictor of survival than body weight in ovarian cancer patients, but the direction of this relationship has not been determined. In conclusion, body composition as an indicator of nutritional status is a better prognostic tool than body weight or BMI alone in ovarian cancer patients.

  14. Body composition in patients with schizophrenia: Comparison with healthy controls

    Directory of Open Access Journals (Sweden)

    Sugawara Norio

    2012-05-01

    Full Text Available Abstract Background Recently, a relationship between obesity and schizophrenia has been reported. Although fat- mass and fat free mass have been shown to be more predictive of health risk than body mass index, there are limited findings about body composition among patients suffering from schizophrenia. The aim of this study is to compare the body composition of schizophrenia patients with that of healthy subjects in Japan. Methods We recruited patients (n = 204, aged 41.3 ± 13.8 (mean ± SD years old with the DSM-IV diagnosis of schizophrenia who were admitted to psychiatric hospital using a cross-sectional design. Subjects' anthropometric measurements including weight, height, body mass index (BMI, and medications were also collected. Body fat, percent (% body fat, fat- free mass, muscle mass, and body water were measured using the bioelectrical impedance analysis (BIA method. Comparative analysis was performed with schizophrenic subjects and 204 healthy control individuals. Results In a multiple regression model with age, body mass index, and dose in chlorpromazine equivalents, schizophrenia was a significantly linked with more body fat, higher % body fat, lower fat- free mass, lower muscle mass, and lower body water among males. In females, schizophrenia had a significant association with lower % body fat, higher fat- free mass, higher muscle mass, and higher body water. Conclusions Our data demonstrate gender differences with regard to changes in body composition in association with schizophrenia. These results indicate that intervention programs designed to fight obesity among schizophrenic patients should be individualized according to gender.

  15. Vertebral body bone strength: the contribution of individual trabecular element morphology.

    Science.gov (United States)

    Parkinson, I H; Badiei, A; Stauber, M; Codrington, J; Müller, R; Fazzalari, N L

    2012-07-01

    Although the amount of bone explains the largest amount of variability in bone strength, there is still a significant proportion unaccounted for. The morphology of individual bone trabeculae explains a further proportion of the variability in bone strength and bone elements that contribute to bone strength depending on the direction of loading. Micro-CT imaging enables measurement of bone microarchitecture and subsequently mechanical strength of the same sample. It is possible using micro-CT data to perform morphometric analysis on individual rod and plate bone trabeculae using a volumetric spatial decomposition algorithm and hence determine their contribution to bone strength. Twelve pairs of vertebral bodies (T12/L1 or L4/L5) were harvested from human cadavers, and bone cubes (10 × 10 × 10 mm) were obtained. After micro-CT imaging, a volumetric spatial decomposition algorithm was applied, and measures of individual trabecular elements were obtained. Bone strength was measured in compression, where one bone specimen from each vertebral segment was tested supero-inferiorly (SI) and the paired specimen was tested antero-posteriorly (AP). Bone volume fraction was the strongest individual determinant of SI strength (r(2) = 0.77, p body bone architecture into its constituent morphological elements shows that trabecular element morphology has specific functional roles to assist in maintaining skeletal integrity.

  16. Effects of Ramadan fasting on body composition and arterial stiffness.

    Science.gov (United States)

    Sezen, Yusuf; Altiparmak, Ibrahim Halil; Erkus, Muslihittin Emre; Kocarslan, Aydemir; Kaya, Zekeriya; Gunebakmaz, Ozgur; Demirbag, Recep

    2016-12-01

    To examine the effects of Ramadan fasting on body composition, arterial stiffness and resting heart rate. This prospective study was conducted at the Department of Cardiology, Harran University, Sanliurfa, Turkey, during Ramadan 2015, and comprised overweight and obese males. Body composition, arterial stiffness and echocardiography were assessed before and after Ramadan. Body composition was assessed by bioelectrical impedance analysis using segmental body composition analyser. Arterial stiffness and haemodynamic parameters were also measured. SPSS 20 was used for data analysis. Of the 100 subjects enrolled, 70(70%) were included. The overall mean age was 37±7 years. No significant changes were observed in blood pressures, resting heart rate, aortic pulse wave velocity, aortic augmentation index-75, aortic pulse pressure, brachial pulse pressure, basal metabolic rate, total body water, fat-free mass, and echocardiographic parameters (p>0.05 each). Although aortic pulse wave velocity (m/s) and augmentation index-75 (%) decreased after fasting period compared to that of before Ramadan, these reductions did not reach statistically significant levels (8.6±1.8 vs. 8.9±1.9, and 13.6±6.6 vs. 14.7±9.3, respectively; p>0.05 each). Body mass index, waist-hip ratio, body water rate, percentage of body fat mass, body fat mass, and visceral fat mass percentage were significantly reduced (pRamadan. Ramadan fasting had beneficial effects on body composition, but did not have any significant effect on arterial stiffness and resting heart rate.

  17. Injury frequency and body composition of elite Romanian rugby players

    Directory of Open Access Journals (Sweden)

    Bogdan ALMĂJAN-GUȚĂ

    2017-03-01

    Full Text Available Background: The physical exertion in the game of rugby is intense and depends on the playing position. This study hypothesized that peculiarities of body composition are important and should be properly interpreted in order to improve fitness and particularly in order to reduce the risk of injuries. Purpose: The aim of the present paper is to highlight the importance of body composition evaluation and to underline the usefulness of the data thus obtained for both training individualization and sports injuries risk reduction. Material and Methods: Thirty seven senior male rugby players from the former Romanian national team were assessed on body composition using a segmental multi-frequency bio-impedance analyzer InBody 720 (The Body Composition Analyzer – South Korea. We compared the results from both the preseason and the regular season 2012 with the international norms for elite players and we categorized the data by playing positions. Results: We have analyzed the amount of lean mass on each limb (kg, body water content (l, percentage of body fat, bone mineral and protein content (kg. We observed that the number of injuries is directly correlated to high levels of body fat percentage, low lean mass, and edema scores. Conclusions: The risk of injury can be identified among elite rugby players not only by using fitness tests, but also by using a simple and objective test of body composition. These results show how important it is to monitor the level of body fat, lean muscle mass and muscular development in order to modify nutrition and food habits, individualize trainings and thus reduce the number of injuries.

  18. About the possibility of obtaining cementitious soil composites of high strength on the basis of belozems of carbonate composition

    Science.gov (United States)

    Karapetyan, K. A.; Hayroyan, S. G.; Manukyan, E. S.

    2018-04-01

    The problem of manufacturing high strength cementitious soils based on belozems of carbonate composition, which experience compression (no less than 10 MPa), without application of surface active substances is considered. The portland cement of type 400 was used as a binding agent to develop compositions of cementitious soil composites, and the ordinary pipe water was used to obtain solutions of cementitious soils. The chemical and mineralogical composition of the initial ingredients and the granulometric composition of belozems were determined. The measurements showed that the upper and lower plasticity limits, the optimum moisture content, and the maximal density of the skeleton of belozems, as well as the considered compositions of cementitious soils, are insignificant, while the plasticity index of cementitious soils is less than one for belozems. It is experimentally proved that an increase in the portland cement amount lead to an increase in the compressive strength of cementitious soils with a decreasing speed. But for the same amount of portland cement used in the cementitious soil compositions, the values of the strength ratio of the pieces tested at the age of 60 and 28 days remain the same and are approximately equal to 1.2. A comparison of experimental data showed that it seems to be real to manufacture a cementitious soil on the basis of belozems of carbonate composition, which contain 10% of cement of the weight of dry mixture and have strength more than 10 MPa, without adding any surfactants to the material composition.

  19. Analytical Solution of Interface Effect on the Strength of Combined Model Composed of Different Geologic Bodies

    Directory of Open Access Journals (Sweden)

    Zeng-hui Zhao

    2014-01-01

    Full Text Available According to the special combined structure of surrounding rock in western mining area of China, a micromechanical model with variable parameters containing contact interface was proposed firstly. Then, the derived stresses in coal and rock near the interface were analyzed on the basis of the harmonized strain relation, and the analytical solutions with respect to stress states near the interface were drawn up. The triaxial compressive strength of coal and rock was further determined in case the contact interface was in the horizontal position. Moreover, effects of stiffness ratio, interface angle, and stress level on the strength of two bodies near the contact area were expounded in detail. Results indicate that additional stresses which have significant effect on the strength of combined model are derived due to the adhesive effect of contact interface and lithological differences between geologic bodies located on both sides. The interface effect on the strength of combined body is most associated with the stiffness, interface angle, and the stress level. These conclusions are also basically valid for three-body model and even for the multibody model and lay important theory foundation to guide the stability study of soft strata composed of different geologic bodies.

  20. Method for Forming Fiber Reinforced Composite Bodies with Graded Composition and Stress Zones

    Science.gov (United States)

    Singh, Mrityunjay (Inventor); Levine, Stanley R. (Inventor); Smialek, James A. (Inventor)

    1999-01-01

    A near-net, complex shaped ceramic fiber reinforced silicon carbide based composite bodies with graded compositions and stress zones is disclosed. To provide the composite a fiber preform is first fabricated and an interphase is applied by chemical vapor infiltration, sol-gel or polymer processes. This first body is further infiltrated with a polymer mixture containing carbon, and/or silicon carbide, and additional oxide, carbide, or nitride phases forming a second body. One side of the second body is spray coated or infiltrated with slurries containing high thermal expansion and oxidation resistant. crack sealant phases and the other side of this second body is coated with low expansion phase materials to form a third body. This third body consisting of porous carbonaceous matrix surrounding the previously applied interphase materials, is then infiltrated with molten silicon or molten silicon-refractory metal alloys to form a fourth body. The resulting fourth body comprises dense composites consisting of fibers with the desired interphase which are surrounded by silicon carbide and other second phases materials at the outer and inner surfaces comprising material of silicon, germanium, refractory metal suicides, borides, carbides, oxides, and combinations thereof The resulting composite fourth body has different compositional patterns from one side to the other.

  1. Fracture strength testing of crowns made of CAD/CAM composite resins.

    Science.gov (United States)

    Okada, Ryota; Asakura, Masaki; Ando, Akihiro; Kumano, Hirokazu; Ban, Seiji; Kawai, Tatsushi; Takebe, Jun

    2018-03-28

    The purpose of this study was to ascertain whether computer aided design/computer aided manufacturing (CAD/CAM) composite resin crowns have sufficient strength to withstand the bite force of the molar teeth. The null hypothesis was that the fracture strength of CAD/CAM composite resin crowns is lower than the average maximum bite force of the molar tooth. The crowns, which shape is the right maxillary first molar, were fabricated using four CAD/CAM blanks made of composite resins (Block HC: HC, KZR-CAD HR: HR, KZR-CAD HR2: HR2, Avencia Block: AVE) and one CAD/CAM blank made of lithium disilicate glass-ceramic (IPS e.max CAD: IPS), which was used as a control. Fracture strength of fabricated crowns bonded to metal abutment and biaxial flexural strength of the materials were evaluated. The results of fracture strength test and biaxial flexural strength test showed different tendencies. The fracture strength of CAD/CAM composite resin crowns except HC ranged from 3.3kN to 3.9kN, and was similar to that of IPS (3.3kN). In contrast, biaxial flexural strength of CAD/CAM composite resins ranged from 175MPa to 247MPa, and was significantly lower than that of IPS (360MPa). All CAD/CAM composite resin crowns studied presented about 3-4 times higher fracture strength than the average maximum bite force of the molar tooth (700-900N), which result leads to the conclusion that CAD/CAM composite resin crowns would have sufficient strength to withstand the bite force of the molar teeth. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  2. Microtensile bond strength of bulk-fill restorative composites to dentin.

    Science.gov (United States)

    Mandava, Jyothi; Vegesna, Divya-Prasanna; Ravi, Ravichandra; Boddeda, Mohan-Rao; Uppalapati, Lakshman-Varma; Ghazanfaruddin, M D

    2017-08-01

    To facilitate the easier placement of direct resin composite in deeper cavities, bulk fill composites have been introduced. The Mechanical stability of fillings in stress bearing areas restored with bulk-fill resin composites is still open to question, since long term clinical studies are not available so far. Thus, the objective of the study was to evaluate and compare the microtensile bond strength of three bulk-fill restorative composites with a nanohybrid composite. Class I cavities were prepared on sixty extracted mandibular molars. Teeth were divided into 4 groups (n= 15 each) and in group I, the prepared cavities were restored with nanohybrid (Filtek Z250 XT) restorative composite in an incremental manner. In group II, III and IV, the bulk-fill composites (Filtek, Tetric EvoCeram, X-tra fil bulk-fill restoratives) were placed as a 4 mm single increment and light cured. The restored teeth were subjected to thermocycling and bond strength testing was done using instron testing machine. The mode of failure was assessed by scanning electron microscope (SEM). The bond strength values obtained in megapascals (MPa) were subjected to statistical analysis, using SPSS/PC version 20 software.One-way ANOVA was used for groupwise comparison of the bond strength. Tukey's Post Hoc test was used for pairwise comparisons among the groups. The highest mean bond strength was achieved with Filtek bulk-fill restorative showing statistically significant difference with Tetric EvoCeram bulk-fill ( p composites. Adhesive failures are mostly observed with X-tra fil bulk fill composites, whereas mixed failures are more common with other bulk fill composites. Bulk-fill composites exhibited adequate bond strength to dentin and can be considered as restorative material of choice in posterior stress bearing areas. Key words: Bond strength, Bulk-fill restoratives, Configuration factor, Polymerization shrinkage.

  3. Body composition in chemotherapy: the promising role of CT scans.

    Science.gov (United States)

    Prado, Carla M M

    2013-09-01

    Reducing cancer-treatment toxicity was a largely ignored research agenda, which is now emerging as an active area of investigation. Studies of human body composition using computerized tomography scans have provided proof-of-concept that variability in drug disposition and toxicity profiles may be partially explained by different features in body composition. Collectively, studies suggest that skeletal muscle depletion (regardless of body weight) is an independent predictor of severe toxicity, affecting cancer treatment and its outcomes. Although precise mechanisms are unknown, pharmacokinetic parameters such as variations in volume of distribution and increased drug exposure may explain such findings. Computerized tomography scans are readily available in clinical databases of diagnostic images and provide feasible, reliable, and highly differentiated measurements of body composition. These images should be used to optimize screening and management of patients in order to prevent severe toxicity, and to improve the efficacy and cost-efficiency of chemotherapy treatments.

  4. Growth and Body Composition of School-Aged Children

    DEFF Research Database (Denmark)

    Dalskov, Stine-Mathilde

    growth or remodeling. Seasonal variations in growth and changes in body composition, if present, are of interest when trying to understand the regulation of growth. They may also be important to be aware of when assessing growth and body composition during shorter periods of time. The overall aim...... of this thesis was to identify factors influencing or associated with growth and body composition of 8-11 year old children. Four specific research questions were specified: 1.) Does a school meal intervention based on the New Nordic Diet (NND) influence height, body mass index (BMI) z-score, waist circumference...... school meals based on a NND for three months and for another three months they ate packed lunch brought from home (control). At baseline, between the two dietary periods, and after the last dietary period children went through a number of investigations. In paper I we showed that ad libitum school meals...

  5. Stiffness and strength degradation of damaged truss core composites

    Czech Academy of Sciences Publication Activity Database

    Šiška, Filip; Tawfeeq, Arwa F.; Dlouhý, I.; Barnett, M.R.

    2015-01-01

    Roč. 125, JUL (2015), s. 287-294 ISSN 0263-8223 R&D Projects: GA MŠk EE2.3.20.0197 Institutional support: RVO:68081723 Keywords : Truss core composites * Finite element * Strain rate * High temperature tests Subject RIV: JI - Composite Materials Impact factor: 3.853, year: 2015

  6. Proandrogenic and Antiandrogenic Progestins in Transgender Youth: Differential Effects on Body Composition and Bone Metabolism.

    Science.gov (United States)

    Tack, Lloyd J W; Craen, Margarita; Lapauw, Bruno; Goemaere, Stefan; Toye, Kaatje; Kaufman, Jean-Marc; Vandewalle, Sara; T'Sjoen, Guy; Zmierczak, Hans-Georg; Cools, Martine

    2018-06-01

    Progestins can be used to attenuate endogenous hormonal effects in late-pubertal transgender (trans) adolescents (Tanner stage B4/5 and G4/5). Currently, no data are available on the effects of progestins on the development of bone mass or body composition in trans youth. To study prospectively the evolution of body composition and bone mass in late-pubertal trans adolescents using the proandrogenic or antiandrogenic progestins lynestrenol (L) and cyproterone acetate (CA), respectively. Forty-four trans boys (Tanner B4/5) and 21 trans girls (Tanner G4/5) were treated with L or CA for 11.6 (4 to 40) and 10.6 (5 to 31) months, respectively. Anthropometry, grip strength, body composition, and bone mass, size, and density were determined by dual-energy X-ray absorptiometry and peripheral quantitative computed tomography before the start of progestin and before addition of cross-sex hormones. Using L, lean mass [+3.2 kg (8.6%)] and grip strength [+3 kg (10.6%)] significantly increased, which coincided with a more masculine body shape in trans boys. Trans girls showed loss of lean mass [-2.2 kg (4.7%)], gain of fat mass [+1.5 kg (9.4%)], and decreased grip strength Z scores. CA limited normal bone expansion and impeded pubertal bone mass accrual, mostly at the lumbar spine [Z score: -0.765 to -1.145 (P = 0.002)]. L did not affect physiological bone development. Proandrogenic and antiandrogenic progestins induce body composition changes in line with the desired appearance within 1 year of treatment. Bone health, especially at the lumbar spine, is of concern in trans girls, as bone mass accrual is severely affected by androgen suppressive therapy.

  7. Carbon fiber/carbon nanotube reinforced hierarchical composites: Effect of CNT distribution on shearing strength

    DEFF Research Database (Denmark)

    Zhou, H. W.; Mishnaevsky, Leon; Yi, H. Y.

    2016-01-01

    The strength and fracture behavior of carbon fiber reinforced polymer composites with carbon nanotube (CNT) secondary reinforcement are investigated experimentally and numerically. Short Beam Shearing tests have been carried out, with SEM observations of the damage evolution in the composites. 3D...... CNT nanoreinforcement into the matrix and/or the sizing of carbon fiber/reinforced composites ensures strong increase of the composite strength. The effect of secondary CNTs reinforcement is strongest when some small addition of CNTs in the polymer matrix is complemented by the fiber sizing with high...... multiscale computational (FE) models of the carbon/polymer composite with varied CNT distributions have been developed and employed to study the effect of the secondary CNT reinforcement, its distribution and content on the strength and fracture behavior of the composites. It is shown that adding secondary...

  8. Influence of bone porcelain scraps on the physical characteristics and phase composition of a hard porcelain body

    Energy Technology Data Exchange (ETDEWEB)

    Nodeh, A.A.

    2017-07-01

    Hard porcelain is constituted in the alkali oxides-alumina-silica ternary system, and produced by a mixture of clay-feldspar and silica. The most important properties of this porcelain are high mechanical strength, translucency and whiteness. These properties depend on quality of raw material, firing temperature and soaking time. In bone porcelain bone ash was added to body composition up to 50wt.%. Generally hard porcelain and bone porcelain scrap cannot be reused in body composition. Whereas using these scrap could help natural resources. In this research using bon porcelain scraps in hard porcelain body have been investigated. Results show, this substitution decrease firing temperature, linear expansion and increase glass, probability of deformation and total shrinkage. Using 6wt.% bone porcelain scraps to hard porcelain body composition besides improving some properties, increases 1340°C firing mechanical strength two times and helps natural resources. (Author)

  9. Fracture strength of biomimetic composites: scaling views on nacre

    Energy Technology Data Exchange (ETDEWEB)

    Okumura, Ko [Department of Physics, Graduate School of Humanities and Sciences, Ochanomizu University, 2-1-1, Otsuka, Bunkyo-ku, Tokyo 112-8610 (Japan)

    2005-08-10

    Nacre, layered structure on the nanoscale, found inside certain seashells, shows remarkable strength due to the tiny amount of soft glues between hard sheets. In this paper, we develop an anisotropic elastic theory and fracture mechanics for the laminar structure at the level of scaling laws to reproduce the essence of the previous results in a much simpler way.

  10. Direct relationship between breakdown strength and tracking index of composites

    DEFF Research Database (Denmark)

    Madsen, Søren Find; Henriksen, Mogens; Holbøll, Joachim

    2006-01-01

    . The breakdown field strength of specimens cut from similar samples is determined by a new method capable of estimating the stressed volume. The results from the two tests are finally compared and incorporated in a single analytical formula. All test specimens are supplied by Danish manufacturers of wind turbine...

  11. Body composition as measured by in vivo neutron activation analysis

    International Nuclear Information System (INIS)

    Cohn, S.H.; Sawitsky, A.; Vartsky, D.; Yasumura, S.; Zanzi, I.; Gartenhaus, W.; Ellis, K.J.

    1979-01-01

    A large scale study is currently underway on the changes in body composition resulting from the cachexia of malignancy. The ultimate objective of the overall project is to assess the changes in body composition associated with hyperalimentation and other modes of nutritional support to cancer patients. The first phase of this study is now in progress. In this phase, a study is being made of a control group of normal patients to provide baseline data against which data from cancer patients can be evaluated. Total body nitrogen and potassium are measured in a group of normal men and women, and are analyzed as a function of age. Additionally, changes in skeletal mass (total body calcium) are also recorded, and body water is measured simultaneously with the use of tritiated water

  12. Change of body composition in process of power conditional training

    Directory of Open Access Journals (Sweden)

    D.M. Anikieiev

    2015-12-01

    Full Text Available Purpose: to work out recommendations on choosing of exercises for power conditional trainees, considering decrease of fat mass percentage as the purpose. Methods: analysis of changes of body composition of trainees, practicing different kinds of conditional power training. Results: the data about influence of different physical loads on thickness of subcutaneous fat in different parts of body have been generalized. Recommendations on choosing of exercises for power conditional trainees for body composition improving have been presented. It was found that fat loss occurs quicker in upper part of body (subcutaneous and visceral. This is observed with increasing of motor functioning and reducing calories of eating. When training any separate muscular group changes of subcutaneous fat take place not compulsory in body parts, in which the trained group is located. Conclusions: it is purposeful to mainly use basic (multi-joint exercises in power conditional training.

  13. Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded with Nano-Filled Composites

    OpenAIRE

    Chalipa, Javad; Akhondi, Mohammad Sadegh Ahmad; Arab, Sepideh; Kharrazifard, Mohammad Javad; Ahmadyar, Maryam

    2013-01-01

    Objectives: The purpose of this study was to evaluate the shear bond strength (SBS) of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Materials and Methods: Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT) was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel...

  14. Evaluation of residual strength in the basalt fiber reinforced composites under impact damage

    Science.gov (United States)

    Kim, Yun-Hae; Lee, Jin-Woo; Moon, Kyung-Man; Yoon, Sung-Won; Baek, Tae-Sil; Hwang, Kwang-Il

    2015-03-01

    Composites are vulnerable to the impact damage by the collision as to the thickness direction, because composites are being manufactured by laminating the fiber. The understanding about the retained strength after the impact damage of the material is essential in order to secure the reliability of the structure design using the composites. In this paper, we have tried to evaluate the motion of the material according to the kinetic energy and potential energy and the retained strength after impact damage by testing the free fall test of the basalt fiber reinforced composite in the limelight as the environment friendly characteristic.

  15. Bond strength of resin composite to light activated bleached enamel

    African Journals Online (AJOL)

    2015-09-02

    Sep 2, 2015 ... After setting of the cement, a composite resin (Variolink II) block was .... do not completely duplicate the physical and chemical properties of the oral ... peroxide concentrations on the corrosion behavior and surface topography.

  16. Micromechanical modeling of strength and damage of fiber reinforced composites

    Energy Technology Data Exchange (ETDEWEB)

    Mishnaevsky, L. Jr.; Broendsted, P.

    2007-03-15

    The report for the first year of the EU UpWind project includes three parts: overview of concepts and methods of modelling of mechanical behavior, deformation and damage of unidirectional fiber reinforced composites, development of computational tools for the automatic generation of 3D micromechanical models of fiber reinforced composites, and micromechanical modelling of damage in FRC, and phenomenological analysis of the effect of frequency of cyclic loading on the lifetime and damage evolution in materials. (au)

  17. 49 CFR 571.221 - Standard No. 221, School bus body joint strength.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Standard No. 221, School bus body joint strength. 571.221 Section 571.221 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE SAFETY STANDARDS Federal Motor Vehicle Safety Standard...

  18. Effect of whole-body vibration on muscle strength, spasticity, and ...

    African Journals Online (AJOL)

    CP) and is characterized by spasticity and muscle weakness of both lower limbs resulting in decreased walking ability. The purpose of this study was to evaluate the effect of whole body vibration (WBV) training on muscle strength, spasticity, and ...

  19. The Evaluation of Strength Training and Body Plyometric Effects on the Male Basketball Players

    Science.gov (United States)

    Bayram, Metin

    2016-01-01

    This research evaluated the effects of resistance training with upper body plyometric effects on the performance of male basketball players. Sixteen males in the physical education and sport science faculty of Ataturk University were randomly determined into two groups. The experimental group performed a combined strength and plyometric training…

  20. Single fibre and multifibre unit cell analysis of strength and cracking of unidirectional composites

    DEFF Research Database (Denmark)

    Wang, H.W.; Zhou, H.W.; Mishnaevsky, Leon

    2009-01-01

    damageable parts in composites (matrix cracks, fibre/matrix interface damage and fibre fracture) was observed in the simulations. The strength of interface begins to influence the deformation behaviour of the cell only after the fibre is broken. In this case, the higher interface layer strength leads...... to the higher stiffness of the damaged material. The damage in the composites begins by fibre breakage, which causes the interface damage, followed by matrix cracking....

  1. The effect of processing on autohesive strength development in thermoplastic resins and composites

    Science.gov (United States)

    Howes, Jeremy C.; Loos, Alfred C.; Hinkley, Jeffrey A.

    1989-01-01

    In the present investigation of processing effects on the autohesive bond strength of neat polysulfone resin and graphite-reinforced polysulfone-matrix composites measured resin bond strength development in precracked compact tension specimens 'healed' by heating over a contact period at a given temperature. The critical strain energy release rate of refractured composite specimens did not exhibit the strong time or temperature dependence of the neat resin tests; only 80-90 percent of the undamaged fracture energy is recoverable.

  2. Design Optimization of Laminated Composite Structures with Many Local Strength Criteria

    DEFF Research Database (Denmark)

    Lund, Erik

    2012-01-01

    This paper presents different strategies for handling very many local strength criteria in structural optimization of laminated composites. Global strength measures using Kreisselmeier-Steinhauser or p-norm functions are introduced for patch-wise parameterizations, and the efficiency of the metho...

  3. Validation and Reliability of a Novel Test of Upper Body Isometric Strength

    Directory of Open Access Journals (Sweden)

    Bellar David

    2015-09-01

    Full Text Available The purpose of the present investigation was to examine the association of a novel test of upper body isometric strength against a 1RM bench press measurement. Forty college age adults (n = 20 female, n = 20 male; age 22.8 ± 2.8 years; body height 171.6 ± 10.8 cm; body mass 73.5 ± 16.3 kg; body fat 23.1 ± 5.4% volunteered for the present investigation. The participants reported to the lab on three occasions. The first visit included anthropometric measurements and familiarization with both the upper body isometric test and bench press exercise. The final visits were conducted in a randomized order, with one being a 1RM assessment on the bench press and the other consisting of three trials of the upper body isometric assessment. For the isometric test, participants were positioned in a “push-up” style position while tethered (stainless steel chain to a load cell (high frequency anchored to the ground. The peak isometric force was consistent across all three trials (ICC = 0.98 suggesting good reliability. Multiple regression analysis was completed with the predictors: peak isometric force, gender, against the outcome variable 1RM bench press. The analysis resulted in a significant model (r2 = 0.861, p≤0.001 with all predictor variables attaining significance in the model (p<0.05. Isometric peak strength had the greatest effect on the model (Beta = 5.19, p≤0.001. Results from this study suggest that the described isometric upper body strength assessment is likely a valid and reliable tool to determine strength. Further research is warranted to gather a larger pool of data in regard to this assessment.

  4. Validation and Reliability of a Novel Test of Upper Body Isometric Strength.

    Science.gov (United States)

    Bellar, David; Marcus, Lena; Judge, Lawrence W

    2015-09-29

    The purpose of the present investigation was to examine the association of a novel test of upper body isometric strength against a 1RM bench press measurement. Forty college age adults (n = 20 female, n = 20 male; age 22.8 ± 2.8 years; body height 171.6 ± 10.8 cm; body mass 73.5 ± 16.3 kg; body fat 23.1 ± 5.4%) volunteered for the present investigation. The participants reported to the lab on three occasions. The first visit included anthropometric measurements and familiarization with both the upper body isometric test and bench press exercise. The final visits were conducted in a randomized order, with one being a 1RM assessment on the bench press and the other consisting of three trials of the upper body isometric assessment. For the isometric test, participants were positioned in a "push-up" style position while tethered (stainless steel chain) to a load cell (high frequency) anchored to the ground. The peak isometric force was consistent across all three trials (ICC = 0.98) suggesting good reliability. Multiple regression analysis was completed with the predictors: peak isometric force, gender, against the outcome variable 1RM bench press. The analysis resulted in a significant model (r2 = 0.861, p≤0.001) with all predictor variables attaining significance in the model (pIsometric peak strength had the greatest effect on the model (Beta = 5.19, p≤0.001). Results from this study suggest that the described isometric upper body strength assessment is likely a valid and reliable tool to determine strength. Further research is warranted to gather a larger pool of data in regard to this assessment.

  5. Validation and Reliability of a Novel Test of Upper Body Isometric Strength

    Science.gov (United States)

    Bellar, David; Marcus, Lena; Judge, Lawrence W.

    2015-01-01

    The purpose of the present investigation was to examine the association of a novel test of upper body isometric strength against a 1RM bench press measurement. Forty college age adults (n = 20 female, n = 20 male; age 22.8 ± 2.8 years; body height 171.6 ± 10.8 cm; body mass 73.5 ± 16.3 kg; body fat 23.1 ± 5.4%) volunteered for the present investigation. The participants reported to the lab on three occasions. The first visit included anthropometric measurements and familiarization with both the upper body isometric test and bench press exercise. The final visits were conducted in a randomized order, with one being a 1RM assessment on the bench press and the other consisting of three trials of the upper body isometric assessment. For the isometric test, participants were positioned in a “push-up” style position while tethered (stainless steel chain) to a load cell (high frequency) anchored to the ground. The peak isometric force was consistent across all three trials (ICC = 0.98) suggesting good reliability. Multiple regression analysis was completed with the predictors: peak isometric force, gender, against the outcome variable 1RM bench press. The analysis resulted in a significant model (r2 = 0.861, p≤0.001) with all predictor variables attaining significance in the model (p<0.05). Isometric peak strength had the greatest effect on the model (Beta = 5.19, p≤0.001). Results from this study suggest that the described isometric upper body strength assessment is likely a valid and reliable tool to determine strength. Further research is warranted to gather a larger pool of data in regard to this assessment. PMID:26557203

  6. COMPOSITION OF STAFF REVIEW ADVISORY BODIES - 2001

    CERN Multimedia

    Seamus Hegarty / HR; Tel. 74128

    2001-01-01

    For the present staff review, the advisory bodies set up to prepare recommendations are composed as follows : Senior Staff Advancement Committee (SSAC) David O. Williams/it (Convener) Cristoforo Benvenuti/est David Plane/ep Technical Engineers & Administrative Careers Committee (TEACC) Sverre Jarp/it (Chairman) Flemming Pedersen/ps Robin Lauckner/sl Christian Roche/ett Lars Leistam/est Dietrich Schinzel/ep Long-term contract Boards (LTCBs) LTCB 1 (Categories 2 & 5a) Tiziano Camporesi/ep [Convener] - Florence Ranjard/ep [Alternate] Jacques Gruber/ps - Peter Sievers/lhc [Alternate] Thomas Pettersson/est - Michel Mayoud/est [Alternate] Sue Foffano/as - Thierry Lagrange/spl [Alternate] Werner Zapf/hr (Secretary) LTCB 2 (Categories 3, 4, 5b & 5c) Véronique Paris/sl [Convener] - Fabien Perriollat/ps [Alternate] Mats Wilhelmsson/st - Véronique Fassnacht/tis [Alternate] Lucie Linssen/ep - Alfredo Placci/ep [Alternate] Patrick Geeraert/fi - John Cuthb...

  7. Maternal body composition, smoking, and hyperemesis gravidarum.

    Science.gov (United States)

    Vikanes, Ase; Grjibovski, Andrej M; Vangen, Siri; Gunnes, Nina; Samuelsen, Sven O; Magnus, Per

    2010-08-01

    To study associations between maternal prepregnant body mass index (BMI), smoking, and hyperemesis gravidarum (hyperemesis). The sample consisted of 33,467 primiparous women from the Norwegian Mother and Child Cohort Study (1999-2008). Data on hyperemesis, BMI, education, maternal age, eating disorders, maternal and paternal smoking habits were obtained from questionnaires. All associations were studied by logistic regression. Altogether, 353 (1.1%) women had hyperemesis. Among non-smokers, both underweight and obese women were more likely to develop hyperemesis than normal-weighted women: odds ratio (OR), 2.36; 95% confidence interval (95% CI), 1.43-3.88 and OR, 1.48; 95% CI, 1.00-2.20, respectively. No associations were found among smokers. Women who smoked daily (OR, 0.44; 95% CI, 0.32-0.60) or occasionally (OR, 0.64; 95% CI, 0.44-0.93) had lower risk of hyperemesis than non-smokers. No effect of partner's smoking habits was observed. Both underweight and obesity were associated with hyperemesis, but only among non-smokers. Maternal prepregnant smoking reduced the risk of hyperemesis, whereas partner's smoking habits had no effect. 2010 Elsevier Inc. All rights reserved.

  8. Composition of Staff Review Advisory Bodies - 2003

    CERN Multimedia

    2003-01-01

    For the present staff review, the advisory bodies set up to prepare recommendations are composed as follows : Senior Staff Advancement Committee (SSAC) David Plane/EP [Convener] Enrico Chiaveri/AB Peter Schmid/EP Technical Engineers & Administrative Careers Committee (TEACC) Robin Lauckner/AB [Chairman]Marcel Mottier/EST Michael Letheren/EP Louis Walckiers/AT Lucie Linssen/EP Mats Wilhelmsson/ST Long-term contract Boards (LTCBs) LTCB 1 (Categories 2 & 5a) Tiziano Camporesi/EP [Convener]Florence Ranjard/EP [Alternate] Roger Bailey/ABPeter Sievers/AT " " Doris Forkel-Wirth/TISPierre Ninin/ST " " Rob Rayson/HRMaarten Wilbers/DSU " " Seamus Hegarty/HR [Secretary] LTCB 2 (Categories 3, 4, 5b & 5c) Véronique Paris/AB [Convener]Fabien Perriollat/AB [Alternate] Christian Lasseur/ESTRamon Folch/EST " " Lucie Linssen/EP Alfredo Placci/EP " " Mats Møller/ASLaszlo Abel/SPL " " Seamus Hegarty/HR [Secretary] Human Resources Division Tel. 74128

  9. COMPOSITION OF STAFF REVIEW ADVISORY BODIES - 2002

    CERN Multimedia

    Human Resources Division

    2002-01-01

    For the present staff review, the advisory bodies set up to prepare recommendations are composed as follows: Senior Staff Advancement Committee (SSAC) Cristoforo BENVENUTI/EST [Convener] David PLANE/EP Peter SCHMID/EP Technical Engineers & Administrative Careers Committee (TEACC) Robin LAUCKNER/SL [Chairman] Flemming PEDERSEN/PS Lucie LINSSEN/EP Dietrich SCHINZEL/EP Marcel MOTTIER/EST Louis WALCKIERS/LHC Long-term contract Boards (LTCBs) (Categories 2 & 5a) Tiziano CAMPORESI/EP [Convener] Florence RANJARD/EP [Alternate] Jacques GRUBER/PS [until 30.6.2002] Roger BAILEY/SL [from 1.7. 2002] Peter SIEVERS/LHC [Alternate] Doris FORKEL-WIRTH/TIS Pierre NININ/ST [Alternate] Sue FOFFANO/AS Maarten WILBERS/DSU [Alternate] Werner ZAPF/HR[Secretary] LTCB 2 Categories 3, 4, 5b & 5c) Véronique PARIS/SL [Convener] Fabien PERRIOLLAT/PS [Alternate] Mats WILHELMSSON/ST Charles NUTTALL/TIS [Alternate] Lucie LINSSEN/EP Alfredo PLACCI/EP [Alternate] Patrick GEERAER...

  10. Development of a Force Measurement Device for Lower-Body Muscular Strength Measuring of Skaters

    Science.gov (United States)

    Kim, Dong Ki; Lee, Jeong Tae

    This paper presents a force measurement system that can measure a lower-body muscular strength of skaters. The precise measurement and analysis of the left and right lower-body strength of skaters is necessary, because a left/right lower-body strength balance is helpful to improve the athletes' performance and to protect them from injury. The system is constructed with a skate sliding board, a couple of sensor-units with load cell, indicator and control box, guard, force pad, and support bracket. The developed force measurement system is calibrated by the calibration setup, and the uncertainty of the force sensing unit on the left is within 0.087% and the uncertainty of the force sensing unit on the right is within 0.109%. In order to check the feasibility of the developed measurement device, a kinematic analysis is conducted with skater. As a result, the subject shows the deviation of left and right of 12.1 N with respect to average strength and 39.1 N with respect to the maximum strength. This evaluation results are reliable enough to make it possible to measure a lower-body muscular strength of skaters. The use of this measurement system will be expected to correct the posture of skaters and record the sports dynamics data for each athlete. It is believed that through the development of this equipment, skaters in elementary, middle, high schools, colleges, and the professional level have the systematic training to compete with world-class skaters.

  11. Evaluating Upper-Body Strength and Power From a Single Test: The Ballistic Push-up.

    Science.gov (United States)

    Wang, Ran; Hoffman, Jay R; Sadres, Eliahu; Bartolomei, Sandro; Muddle, Tyler W D; Fukuda, David H; Stout, Jeffrey R

    2017-05-01

    Wang, R, Hoffman, JR, Sadres, E, Bartolomei, S, Muddle, TWD, Fukuda, DH, and Stout, JR. Evaluating upper-body strength and power from a single test: the ballistic push-up. J Strength Cond Res 31(5): 1338-1345, 2017-The purpose of this study was to examine the reliability of the ballistic push-up (BPU) exercise and to develop a prediction model for both maximal strength (1 repetition maximum [1RM]) in the bench press exercise and upper-body power. Sixty recreationally active men completed a 1RM bench press and 2 BPU assessments in 3 separate testing sessions. Peak and mean force, peak and mean rate of force development, net impulse, peak velocity, flight time, and peak and mean power were determined. Intraclass correlation coefficients were used to examine the reliability of the BPU. Stepwise linear regression was used to develop 1RM bench press and power prediction equations. Intraclass correlation coefficient's ranged from 0.849 to 0.971 for the BPU measurements. Multiple regression analysis provided the following 1RM bench press prediction equation: 1RM = 0.31 × Mean Force - 1.64 × Body Mass + 0.70 (R = 0.837, standard error of the estimate [SEE] = 11 kg); time-based power prediction equation: Peak Power = 11.0 × Body Mass + 2012.3 × Flight Time - 338.0 (R = 0.658, SEE = 150 W), Mean Power = 6.7 × Body Mass + 1004.4 × Flight Time - 224.6 (R = 0.664, SEE = 82 W); and velocity-based power prediction equation: Peak Power = 8.1 × Body Mass + 818.6 × Peak Velocity - 762.0 (R = 0.797, SEE = 115 W); Mean Power = 5.2 × Body Mass + 435.9 × Peak Velocity - 467.7 (R = 0.838, SEE = 57 W). The BPU is a reliable test for both upper-body strength and power. Results indicate that the mean force generated from the BPU can be used to predict 1RM bench press, whereas peak velocity and flight time measured during the BPU can be used to predict upper-body power. These findings support the potential use of the BPU as a valid method to evaluate upper-body strength and power.

  12. Notched Strength of Woven Fabric Kenaf Composites with Different Fiber Orientations

    Directory of Open Access Journals (Sweden)

    Ahmad Hilton

    2017-01-01

    Full Text Available The awareness of implementing sustainable materials in construction industry is gaining good attention among engineers worldwide. Kenaf fibers are local renewable materials to combine with epoxy polymers matrix in producing lightweight composite materials which may replace imported synthetic fiber composites especially in developing countries. Other benefits of using kenaf fiber composites are relatively cheap, less abrasive and less hazardous during fabrication handling. Current study investigates parametric study on notched strength of woven fabric kenaf composite plates with different fiber orientations and circular hole sizes. Stress concentration occurred at the notch edge promotes to micro-damage events such as matrix cracking and fiber fracture as remote tensile loading applied. Current study showed that 0° fiber orientation gives optimum notched strength, plates with larger fiber tilting than 0° are associated with further strength reduction. Kenaf fibers give an alternative to material designers to opt woven fabric kenaf composites in low and medium load bearing applications.

  13. Body Composition Assessment from Birth to Two Years of Age

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-15

    During infancy and early childhood, the pace and quality of growth mark the risk of ill health in the short and longer term. Measurements of body weight and its changes are frequently taken as indicators of growth, without adequate attention being paid to linear growth or body composition during this critical window of opportunity, as these measurements are more challenging to make. To better define and characterize healthy growth, there is a need for guidance on the use of standardized methodologies to assess body composition during early life to differentiate between nutrient partitioning to fat free mass and to fat mass in infants and young children. Given the necessity for an international consensus, in 2009 the IAEA initiated a review of body composition assessment techniques as the basis for efforts aimed at the standardization of body composition assessment from birth to 2 years of age. This initiative follows the IAEA's long standing tradition of providing guidance on the use of nuclear techniques in nutrition. This publication was developed by an international group of experts as an integral part of the IAEA's contribution to the transfer of technology and capacity building in this field to assist Member States in their efforts to improve the nutrition and health of infants and young children, who are among the most vulnerable population groups. This publication provides practical information on the assessment of body composition from birth up to 2 years of age and is intended for nutritionists, paediatricians and other health professionals. The body composition assessment techniques included in this publication were considered the methodologies with the highest potential for standardization globally - based on considerations such as access to equipment, cost and the training needs of staff - and include stable isotope dilution for total body water assessment as well as dual energy X ray absorptiometry and air displacement plethysmography. In addition, the

  14. Body Composition Assessment from Birth to Two Years of Age

    International Nuclear Information System (INIS)

    2013-01-01

    During infancy and early childhood, the pace and quality of growth mark the risk of ill health in the short and longer term. Measurements of body weight and its changes are frequently taken as indicators of growth, without adequate attention being paid to linear growth or body composition during this critical window of opportunity, as these measurements are more challenging to make. To better define and characterize healthy growth, there is a need for guidance on the use of standardized methodologies to assess body composition during early life to differentiate between nutrient partitioning to fat free mass and to fat mass in infants and young children. Given the necessity for an international consensus, in 2009 the IAEA initiated a review of body composition assessment techniques as the basis for efforts aimed at the standardization of body composition assessment from birth to 2 years of age. This initiative follows the IAEA's long standing tradition of providing guidance on the use of nuclear techniques in nutrition. This publication was developed by an international group of experts as an integral part of the IAEA's contribution to the transfer of technology and capacity building in this field to assist Member States in their efforts to improve the nutrition and health of infants and young children, who are among the most vulnerable population groups. This publication provides practical information on the assessment of body composition from birth up to 2 years of age and is intended for nutritionists, paediatricians and other health professionals. The body composition assessment techniques included in this publication were considered the methodologies with the highest potential for standardization globally - based on considerations such as access to equipment, cost and the training needs of staff - and include stable isotope dilution for total body water assessment as well as dual energy X ray absorptiometry and air displacement plethysmography. In addition, the

  15. A comparison of men's and women's strength to body mass ratio and varus/valgus knee angle during jump landings.

    Science.gov (United States)

    Haines, Tracie L; McBride, Jeffrey M; Triplett, N Travis; Skinner, Jared W; Fairbrother, Kimberly R; Kirby, Tyler J

    2011-10-01

    The purpose of this investigation was to compare valgus/varus knee angles during various jumps and lower body strength between males and females relative to body mass. Seventeen recreationally active females (age: 21.94 ± 2.59 years; height: 1.67 ± 0.05 m; mass: 64.42 ± 8.39 kg; percent body fat: 26.89 ± 6.26%; squat one-repetition maximum: 66.18 ± 19.47 kg; squat to body mass ratio: 1.03 ± 0.28) and 13 recreationally active males (age: 21.69 ± 1.65 years; height: 1.77 ± 0.07 m; mass: 72.39 ± 9.23 kg; percent body fat: 13.15 ± 5.18%; squat one-repetition maximum: 115.77 ± 30.40 kg; squat to body mass ratio: 1.59 ± 0.31) performed a one-repetition maximum in the squat and three of each of the following jumps: countermovement jump, 30 cm drop jump, 45 cm drop jump, and 60 cm drop jump. Knee angles were analysed using videography and body composition was analysed by dual-energy X-ray absorptiometry to allow for squat to body mass ratio and squat to fat free mass ratio to be calculated. Significant differences (P ≤ 0.05) were found between male and female one-repetition maximum, male and female squat to body mass ratio, and male and female squat to fat free mass ratio. Significant differences were found between male and female varus/valgus knee positions during maximum flexion of the right and left leg in the countermovement jump, drop jump from 30 cm, drop jump from 45 cm, and drop jump from 60 cm. Correlations between varus/valgus knee angles and squat to body mass ratio for all jumps displayed moderate, non-significant relationships (countermovement jump: r = 0.445; drop jump from 30 cm: r = 0.448; drop jump from 45 cm: r = 0.449; drop jump from 60 cm: r = 0.439). In conclusion, males and females have significantly different lower body strength and varus/valgus knee position when landing from jumps.

  16. Comparison of anthropometry, upper-body strength, and lower-body power characteristics in different levels of Australian football players.

    Science.gov (United States)

    Bilsborough, Johann C; Greenway, Kate G; Opar, David A; Livingstone, Steuart G; Cordy, Justin T; Bird, Stephen R; Coutts, Aaron J

    2015-03-01

    The aim of this study was to compare the anthropometry, upper-body strength, and lower-body power characteristics in elite junior, sub-elite senior, and elite senior Australian Football (AF) players. Nineteen experienced elite senior (≥4 years Australian Football League [AFL] experience), 27 inexperienced elite senior (free soft tissue mass [FFSTM], fat mass, and bone mineral content) with dual-energy x-ray absorptiometry, upper-body strength (bench press and bench pull), and lower-body power (countermovement jump [CMJ] and squat jump with 20 kg). A 1-way analysis of variance assessed differences between the playing levels in these measures, whereas relationships between anthropometry and performance were assessed with Pearson's correlation. The elite senior and sub-elite senior players were older and heavier than the elite junior players (p ≤ 0.05). Both elite playing groups had greater total FFSTM than both the sub-elite and junior elite players; however, there were only appendicular FFSTM differences between the junior elite and elite senior players (p squat performance measures (r = 0.33-0.55). Australian Football players' FFSTM are different between playing levels, which are likely because of training and partly explain the observed differences in performance between playing levels highlighting the importance of optimizing FFSTM in young players.

  17. Longitudinal study of body composition in spinal cord injury patients

    Directory of Open Access Journals (Sweden)

    Roop Singh

    2014-01-01

    Full Text Available Background: Bone mass loss and muscle atrophy are the frequent complications occurring after spinal cord injury (SCI. The potential risks involved with these changes in the body composition have implications for the health of the SCI individual. Thus, there is a need to quantitate and monitor body composition changes accurately in an individual with SCI. Very few longitudinal studies have been reported in the literature to assess body composition and most include relatively small number of patients. The present prospective study aimed to evaluate the body composition changes longitudinally by DEXA in patients with acute SCI. Materials and Methods: Ninety five patients with acute SCI with neurological deficits were evaluated for bone mineral content (BMC, body composition [lean body mass (LBM and fat mass] by dual-energy X-ray absorptiometry during the first year of SCI. Results: There was a significant decrease in BMC ( P < 0.05 and LBM ( P < 0.05 and increase in total body fat mass (TBFM and percentage fat at infra-lesional sites. The average decrease was 14.5% in BMC in lower extremities, 20.5% loss of LBM in legs and 15.1% loss of LBM in trunk, and increase of 0.2% in fat mass in legs and 17.3% increased fat in the lower limbs at 1 year. The tetraplegic patients had significant decrease in arm BMC ( P < 0.001, arm LBM ( P < 0.01 and fat percentage ( P < 0.01 compared to paraplegics. Patients with complete motor injury had higher values of TBFM and fat percentage, but comparable values of BMC and LBM to patients with incomplete motor injury. Conclusions: Our findings suggest that there is a marked decrease in BMC and LBM with increase in adiposity during the first year of SCI. Although these changes depend on the level and initial severity of lesions, they are also influenced by the neurological recovery after SCI.

  18. Strength of cellulosic fiber/starch acetate composites with variable fiber and plasticizer content

    DEFF Research Database (Denmark)

    Joffe, Roberts; Madsen, Bo; Nättinen, Kalle

    2015-01-01

    In this experimental study, the performance of injection-molded short flax and hemp fibers in plasticized starch acetate were analyzed in terms of strength. Parameters involved in the analysis are a variable fiber and plasticizer content. The measured strength of the composites varies in the range...... of 12–51 MPa for flax fibers and 11–42 MPa for hemp fibers, which is significantly higher than the properties of the unreinforced starch acetate matrix. The micro-structural parameters used in modeling of composite strength were obtained from optical observations and indirect measurements. Some...

  19. Interface structure and strength in model dental resin composites

    DEFF Research Database (Denmark)

    Nielsen, Mette Skovgaard

    . This will facilitate discoloration by colorants from e.g. coffee and red wine entering the crack, or even worse lead to secondary caries and infection of dental pulp due to bacteria. The aim of this study was to develop a low shrinkage dental composite based on an expandable metastable zirconia filler A metastable...

  20. Dietary strategies and body composition in elite weightlifting: Systematic Review

    OpenAIRE

    Alejandro Martínez-Rodríguez; Rafael M Tundidor-Duque; Pedro E Alcaraz; Jacobo Á Rubio-Arias

    2017-01-01

    Introduction: There is little literature that showed the nutritional bases to optimize weightlifting performance. The objective was to perform a systematic review of the body composition and nutritional composition of diets in elite weightlifting athletes. Material and Methods: Articles published in Pubmed, Web of Science and Sport Discuss were reviewed following PRISMA Statement. The process for selecting studies was performed duplicated by two researchers in two stages (screening and ap...

  1. [Analysis of the body composition of Spanish women with fibromyalgia].

    Science.gov (United States)

    Aparicio, Virginia A; Ortega, Francisco B; Heredia, José M; Carbonell-Baeza, Ana; Delgado-Fernández, Manuel

    2011-01-01

    To describe the anthropometric profile and body composition of women from Southern Spain diagnosed with fibromyalgia (FM) and to compare the observed values with values from other studies conducted on FM patients and with national reference values. The body composition of 104 women diagnosed with FM was assessed using an eight-electrode impedance meter. The reliability of the body composition measurement was tested in a randomly selected sub-sample (n=28). The reliability study showed a test-retest systematic error close to zero in most of the parameters studied. The women with FM who were studied had a mean weight of 71.3±13.4 kg, height of 158±6 cm, body mass index of 28.6±5.1 kg/m(2), body fat mass of 38.6±7.6%, total body water of 31.6±3.8 l and muscle mass of 23.4±3.0 kg. In general, there were no substantial differences in weight and body mass index between women with FM and those analyzed in other Spanish and European studies involving FM patients, nor when they were compared with regional or national reference values. However, the prevalence of obesity in the women with FM under study was 33.7%, a higher figure than that from the national reference data for obesity in similarly aged women (i.e. 26,4%). The results suggest that obesity is a common condition in women diagnosed with FM, its prevalence in this population being higher than the national reference values. This study provides detailed information about the body composition characteristics of women with FM. Copyright © 2010 Elsevier España, S.L. All rights reserved.

  2. Correlation between Body Composition and Walking Capacity in Severe Obesity

    OpenAIRE

    Correia de Faria Santar?m, G; de Cleva, R; Santo, Marco Aur?lio; Bernhard, Aline Biaseto; Gadducci, Alexandre Vieira; Greve, Julia Maria D?Andrea; Silva, Paulo Roberto Santos

    2015-01-01

    Background Obesity is associated with mobility reduction due to mechanical factors and excessive body fat. The six-minute walk test (6MWT) has been used to assess functional capacity in severe obesity. Objective To determine the association of BMI, total and segmental body composition with distance walked (6MWD) during the six-minute walk test (6MWT) according to gender and obesity grade. Setting University of S?o Paulo Medical School, Brazil; Public Practice. Methods Functional capacity was ...

  3. Impact of fat mass distribution body shapes on muscles strength and the joints pain

    Directory of Open Access Journals (Sweden)

    Zerf Mohammed

    2016-01-01

    Full Text Available Our study focuses on fat mass distribution body shapes type as measured to determine their effect on skeletal muscle strengthening lumbar extensors (upper and lower limbs where our background confirms that every girl has a natural body type of rectangle, apple, pear, or hourglass. It is good for her to know which type of body shape she is, so she can learn what exercises to do, whereas similar studies suggest that it is much better to challenge weight problems with exercise and dietary measures before resorting to figure shaping. For this purpose, our study was carried out with a total of thirty students, females listed in the Institute of Physical Education and Sport, University of Mostaganem, aged between 20 and 23 years; their homogeneity was based on age, sex, and academic specialty, classified based on the body mass index (BMI into two groups (normal and overweight and based on their body shape′s type into three groups (9 pear shape, 10 rectangle shape, and 11 hourglass shape as a protocol experimental to examine the impact of fat mass distribution body shapes type on lumbar extensor strength. Based on our data analysis, we confirm that the pear and the rectangle shape affect the strength lumbar extensors due to body weight distribution which increases the risks relating to the skeletal muscles. Weight gain is a factor contributing to the weakness of skeletal muscles. However, the body shape explains the anomalies of the distribution of fat mass and BMI risk observed in our sample in the lower and upper part of the body recorded by the values of Killy test and endurance of trunk, the case of the pear and the rectangle shape back pain, which are consisting in excess of the body fat distributed in comparison with less percentage of muscle mass. Whereas this difference can affect the pelvic position.

  4. Cues of upper body strength account for most of the variance in men's bodily attractiveness.

    Science.gov (United States)

    Sell, Aaron; Lukazsweski, Aaron W; Townsley, Michael

    2017-12-20

    Evolution equips sexually reproducing species with mate choice mechanisms that function to evaluate the reproductive consequences of mating with different individuals. Indeed, evolutionary psychologists have shown that women's mate choice mechanisms track many cues of men's genetic quality and ability to invest resources in the woman and her offspring. One variable that predicted both a man's genetic quality and his ability to invest is the man's formidability (i.e. fighting ability or resource holding power/potential). Modern women, therefore, should have mate choice mechanisms that respond to ancestral cues of a man's fighting ability. One crucial component of a man's ability to fight is his upper body strength. Here, we test how important physical strength is to men's bodily attractiveness. Three sets of photographs of men's bodies were shown to raters who estimated either their physical strength or their attractiveness. Estimates of physical strength determined over 70% of men's bodily attractiveness. Additional analyses showed that tallness and leanness were also favoured, and, along with estimates of physical strength, accounted for 80% of men's bodily attractiveness. Contrary to popular theories of men's physical attractiveness, there was no evidence of a nonlinear effect; the strongest men were the most attractive in all samples. © 2017 The Author(s).

  5. Relationships Between Lower-Body Muscle Structure and, Lower-Body Strength, Explosiveness and Eccentric Leg Stiffness in Adolescent Athletes

    Directory of Open Access Journals (Sweden)

    Josh L. Secomb, Sophia Nimphius, Oliver R.L. Farley, Lina E. Lundgren, Tai T. Tran, Jeremy M. Sheppard

    2015-12-01

    Full Text Available The purpose of the present study was to determine whether any relationships were present between lower-body muscle structure and, lower-body strength, variables measured during a countermovement jump (CMJ and squat jump (SJ, and eccentric leg stiffness, in adolescent athletes. Thirty junior male (n = 23 and female (n = 7 surfing athletes (14.8 ± 1.7 y; 1.63 ± 0.09 m; 54.8 ± 12.1 kg undertook lower-body muscle structure assessment with ultrasonography and performed a; CMJ, SJ and an isometric mid-thigh pull (IMTP. In addition, eccentric leg stiffness was calculated from variables of the CMJ and IMTP. Moderate to very large relationships (r = 0.46-0.73 were identified between the thickness of the vastus lateralis (VL and lateral gastrocnemius (LG muscles, and VL pennation angle and; peak force (PF in the CMJ, SJ and IMTP. Additionally, moderate to large relationships (r = 0.37-0.59 were found between eccentric leg stiffness and; VL and LG thickness, VL pennation angle, and LG fascicle length, with a large relationship (r = 0.59 also present with IMTP PF. These results suggest that greater thickness of the VL and LG were related to improved maximal dynamic and isometric strength, likely due to increased hypertrophy of the extensor muscles. Furthermore, this increased thickness was related to greater eccentric leg stiffness, as the associated enhanced lower-body strength likely allowed for greater neuromuscular activation, and hence less compliance, during a stretch-shortening cycle.

  6. Properties analysis of tensile strength, crystallinity degree and microstructure of polymer composite polypropylene-sand

    International Nuclear Information System (INIS)

    Sudirman; Karo-Karo, Aloma; Ari-Handayani; Bambang-Sugeng; Rukihati; Mashuri

    2004-01-01

    Materials modification base on polymer toward polymer composite is needed by addition of filler. Mechanical properties such as tensile strength, crystallinity degree and microstructure of polymer composite based on polypropylene with sand filler have been investigated. In this work, the polymer composite has been made by mixing the matrix of polypropylene melt flow 2 (PP MF2) or polypropylene melt flow 10 (PP MF 10) with sand filler in a labo plastomill. The composition of sand filler was varied to 10, 30, 40 and 50 % v/v, a then the composite were casted to the film sheets form. The sheets were characterized mechanically i.e tensile strength, crystallinity degree and microstructure. The result showed that the tensile strength decreased by increasing the volume fraction of sand filler, in accordance with microstructure investigation that the matrix area under zone plastic deformation (more cracks), while the filler experienced elastic deformation, so that the strength mechanism of filler did not achieved with expectation (Danusso and Tieghi theory). For filler more than 30 % of volume fraction, the tensile strength of polypropylene melt flow 10 (PP MF 10) was greater than that polypropylene melt flow 2 (PP MF2). It was caused by plasticities in PP MF 10. The tensile strength of PP MF2 was greater than that PP MF 10 for volume fraction of sand filler less than 30 %. It was caused by PP MF2 to be have more degree of crystallinity

  7. Fracture strength and fatigue resistance of dental resin-based composites

    NARCIS (Netherlands)

    Keulemans, F.; Palav, P.; Aboushelib, M.M.N.; van Dalen, A.; Kleverlaan, C.J.; Feilzer, A.J.

    2009-01-01

    Objectives: The aim of this study was to evaluate in vitro the influence of fiber-reinforcement on the fracture strength and fatigue resistance of resin-based composites. Methods: One hundred rectangular bar-shaped specimens (2 mm × 2 mm × 25 mm) made of resin-based composite were prepared in a

  8. Water absorption and tensile strength degradation of Petung bamboo (Dendrocalamus asper) fiber-reinforced polymeric composites

    NARCIS (Netherlands)

    Judawisastra, H.; Sitohang, Ramona; Rosadi, M. S.

    2017-01-01

    Bamboo fibers have attracted great interest and are believed to have the potential as natural fiber for reinforcing polymer composites. This research aims to study water absorption behavior and its effect to tensile strength of the composites made from petung bamboo fiber, which is one of the most

  9. The behavior of high-strength unidirectional composites under tension with superposed hydrostatic pressure

    NARCIS (Netherlands)

    Zinoviev, P.A.; Tsvetkov, S.V.; Kulish, G.G.; Berg, van den R.W.; Schepdael, van L.J.M.M.

    2001-01-01

    Three types of high-strength unidirectional composite materials were studied under longitudinal tension with superposed high hydrostatic pressure. Reinforcing fibers were T1000G carbon, S2 glass and Zylon PBO fibers; the Ciba 5052 epoxy resin was used as matrix. The composites were tested under

  10. Body composition and risk for metabolic alterations in female adolescents

    Directory of Open Access Journals (Sweden)

    Eliane Rodrigues de Faria

    2014-06-01

    Full Text Available OBJECTIVE: To study anthropometrical and body composition variables as predictors of risk for metabolic alterations and metabolic syndrome in female adolescents.METHODS: Biochemical, clinical and corporal composition data of 100 adolescents from 14 to 17 years old, who attended public schools in Viçosa, Southeastern Brazil, were collected.RESULTS: Regarding nutritional status, 83, 11 and 6% showed eutrophia, overweight/obesity and low weight, respectively, and 61% presented high body fat percent. Total cholesterol presented the highest percentage of inadequacy (57%, followed by high-density lipoprotein (HDL - 50%, low-density lipoprotein (LDL - 47% and triacylglycerol (22%. Inadequacy was observed in 11, 9, 3 and 4% in relation to insulin resistance, fasting insulin, blood pressure and glycemia, respectively. The highest values of the fasting insulin and the Homeostasis Model Assessment-Insulin Resistance(HOMA-IR were verified at the highest quartiles of body mass index (BMI, waist perimeter, waist-to-height ratio and body fat percent. Body mass index, waist perimeter, and waist-to-height ratio were the better predictors for high levels of HOMA-IR, blood glucose and fasting insulin. Waist-to-hip ratio was associated to arterial hypertension diagnosis. All body composition variables were effective in metabolic syndrome diagnosis.CONCLUSIONS: Waist perimeter, BMI and waist-to-height ratio showed to be good predictors for metabolic alterations in female adolescents and then should be used together for the nutritional assessment in this age range.

  11. Prediction on flexural strength of encased composite beam with cold-formed steel section

    Science.gov (United States)

    Khadavi, Tahir, M. M.

    2017-11-01

    A flexural strength of composite beam designed as boxed shaped section comprised of lipped C-channel of cold-formed steel (CFS) facing each other with reinforcement bars is proposed in this paper. The boxed shaped is kept restrained in position by a profiled metal decking installed on top of the beam to form a slab system. This profiled decking slab is cast by using self-compacting concrete where the concrete is in compression when load is applied to the beam. Reinforcement bars are used as shear connector between slab and CFS as beam. A numerical analysis method proposed by EC4 is used to predict the flexural strength of the proposed composite beam. It was assumed that elasto-plastic behaviour is developed in the cross -sectional of the proposed beam. The calculated predicted flexural strength of the proposed beam shows reasonable flexural strength for cold-formed composite beam.

  12. CORRELATION BETWEEN BODY MASS INDEX AND HANDGRIP STRENGTH AND HANDGRIP ENDURANCE AMONG YOUNG HEALTHY ADULTS

    Directory of Open Access Journals (Sweden)

    Anupi

    2015-07-01

    Full Text Available BACKGROUND: Physical inactivity has become a serious problem all over the world. Handgrip Strength (a form of isometric static contraction test, is an important test to evaluate the physical fitness and nutritional status of an individua l. A number of factors like a ge, gender, body size, effort, skeletal muscle bulk and contractility may affect the handgrip strength (HGS and handgrip endurance (HGE. AIM: This study was conducted to establish the possible correlation (if any between body mass index and handgrip str ength and endurance among young healthy adults. MATERIALS AND METHODS: A population based cross - sectional study comprising of 200 students (both male and female, age group - 18 - 22 yrs was carried out in the Department of Physiology, Jorhat Medical College. Anthropometric parameters like height and weight were taken to evaluate the BMI and handgrip strength and handgrip endurance were taken by using handgrip dynamometer. According to WHO classification of BMI, subjects were categorized into three groups as un derweight BMI ≤18.5 kg/m 2 , normal weight BMI 18.5 - 24.9 kg/m 2 and overweight BMI≥ 24.9 kg/m 2 . Gender wise difference was analyzed by unpaired t test. Statistical analysis for correlation was done by using Karl Pearson’s Correlation Coefficient denoted by(r. RESULT: Males had higher handgrip strength and handgrip endurance than females. Statistic ally significant correlation was found between BMI and handgrip strength & endurance in underweight & overweight subjects. Gender differences in correlation were observed in correlation between BMI & HGS and HGE. CONCLUSION: The observed influence of BMI a nd gender differences in correlation between BMI and HGS and HGE indicate that besides BMI several other factors like effort, strength, muscular contractility etc . affect muscular strength & endurance in young males and females.

  13. Efficacy of phosphatidic acid ingestion on lean body mass, muscle thickness and strength gains in resistance-trained men

    Directory of Open Access Journals (Sweden)

    Hoffman Jay R

    2012-10-01

    Full Text Available Abstract Background Phosphatidic acid (PA has been reported to activate the mammalian target of rapamycin (mTOR signaling pathway and is thought to enhance the anabolic effects of resistance training. The purpose of this pilot study was to examine if oral phosphatidic acid administration can enhance strength, muscle thickness and lean tissue accruement during an 8-week resistance training program. Methods Sixteen resistance-trained men were randomly assigned to a group that either consumed 750 mg of PA (n = 7, 23.1 ± 4.4 y; 176.7 ± 6.7 cm; 86.5 ± 21.2 kg or a placebo (PL, n = 9, 22.5 ± 2.0 y; 179.8 ± 5.4 cm; 89.4 ± 13.6 kg group. During each testing session subjects were assessed for strength (one repetition maximum [1-RM] bench press and squat and body composition. Muscle thickness and pennation angle were also measured in the vastus lateralis of the subject’s dominant leg. Results Subjects ingesting PA demonstrated a 12.7% increase in squat strength and a 2.6% increase in LBM, while subjects consuming PL showed a 9.3% improvement in squat strength and a 0.1% change in LBM. Although parametric analysis was unable to demonstrate significant differences, magnitude based inferences indicated that the Δ change in 1-RM squat showed a likely benefit from PA on increasing lower body strength and a very likely benefit for increasing lean body mass (LBM. Conclusions Results of this study suggest that a combination of a daily 750 mg PA ingestion, combined with a 4-day per week resistance training program for 8-weeks appears to have a likely benefit on strength improvement, and a very likely benefit on lean tissue accruement in young, resistance trained individuals.

  14. Body composition assessment in Taiwanese individuals with poliomyelitis.

    Science.gov (United States)

    Chang, Kwang-Hwa; Lai, Chien-Hung; Chen, Shih-Ching; Hsiao, Wen-Tien; Liou, Tsan-Hon; Lee, Chi-Ming

    2011-07-01

    To measure the changes in the total and regional body fat mass, and assess the clinical usefulness of the body mass index (BMI) in detecting overweight subjects with sequelae of poliomyelitis. Prospective, cross-sectional study. General community. Subjects with poliomyelitis (n=17; age range, 42-57y; mean, 47y; 12 men, 5 women) and able-bodied people (n=17) matched by sex, age, body weight, and body height participated in the study. Not applicable. Total and regional body composition was measured with dual-energy x-ray absorptiometry. Clinical characteristics such as blood pressure, serum biochemical studies, and habitual behaviors (daily cigarette smoking, alcohol consumption, and exercise regimen) of all participants were evaluated. Compared with able-bodied controls, subjects with poliomyelitis had a 50% greater total body fat mass, significant increases in the regional fat mass in every part of the body, and had the greatest increase of fat mass in the thorax. Nearly all the subjects (94%) with poliomyelitis were obese according to standards of body composition. However, one third of them had a BMI value of less than 25.0kg/m(2). People with poliomyelitis have a higher prevalence of obesity and a significant increase in total and regional fat mass. Current BMI underestimates the total body fat mass percentage compared with the control; therefore, a population-specific BMI should be used to address the prevalence of obesity in postpolio survivors. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  15. FY98 Final Report Initial Interfacial Chemical Control for Enhancement of Composite Material Strength; TOPICAL

    International Nuclear Information System (INIS)

    GE Fryxell; KL Alford; KL Simmons; RD Voise; WD Samuels

    1999-01-01

    The U.S. Army Armament Research Development and Engineering Center (ARDEC) sponsored this research project to support the development of new self-assembled monolayer fiber coatings. These coatings can greatly increase the bond strength between the fiber and the resin matrix of a composite material. Composite ammunition components molded from such materials will exhibit higher strength than current materials, and will provide a major improvement in the performance of composites in military applications. Use of composite materials in military applications is desirable because of the lighter weight of the materials and their high strengths. The FY97 project investigated initial interfacial chemical control for enhancement of composite material strength. The core of the project was to modify the covalent interface of glass fibers (or other reinforcing fibers) to induce strong, uniform, defect-free adhesion between the fibers' surfaces and the polymer matrix. Installing a self-assembled monolayer tailored to the specific matrix resin accomplished this. Simply, the self-assembled monolayer modifies the fiber to make it appear to have the same chemical composition as the resin matrix. The self-assembled monolayer creates a receptive, hydrophobic interface that the thermoset resin (or polymer precursors) would wet more effectively, leading to a higher contact surface area and more efficient adhesion. The FY97 work phase demonstrated that it is possible to increase the adhesive strength, as well as increase the heat deflection temperature through the use of self-assembled monolayer

  16. Adhesive properties and adhesive joints strength of graphite/epoxy composites

    Science.gov (United States)

    Rudawska, Anna; Stančeková, Dana; Cubonova, Nadezda; Vitenko, Tetiana; Müller, Miroslav; Valášek, Petr

    2017-05-01

    The article presents the results of experimental research of the adhesive joints strength of graphite/epoxy composites and the results of the surface free energy of the composite surfaces. Two types of graphite/epoxy composites with different thickness were tested which are used to aircraft structure. The single-lap adhesive joints of epoxy composites were considered. Adhesive properties were described by surface free energy. Owens-Wendt method was used to determine surface free energy. The epoxy two-component adhesive was used to preparing the adhesive joints. Zwick/Roell 100 strength device were used to determination the shear strength of adhesive joints of epoxy composites. The strength test results showed that the highest value was obtained for adhesive joints of graphite-epoxy composite of smaller material thickness (0.48 mm). Statistical analysis of the results obtained, the study showed statistically significant differences between the values of the strength of the confidence level of 0.95. The statistical analysis of the results also showed that there are no statistical significant differences in average values of surface free energy (0.95 confidence level). It was noted that in each of the results the dispersion component of surface free energy was much greater than polar component of surface free energy.

  17. Eicosapentaenoic acid in cancer improves body composition and modulates metabolism.

    Science.gov (United States)

    Pappalardo, Giulia; Almeida, Ana; Ravasco, Paula

    2015-04-01

    The objective of this review article is to present the most recent intervention studies with EPA on nutritional outcomes in cancer patients, e.g. nutritional status, weight & lean body mass. For this purpose a PubMed(®) and MedLine(®) search of the published literature up to and including January 2014 that contained the keywords: cancer, sarcopenia, EPA, ω-3 fatty acids, weight, intervention trial, muscle mass was conducted. The collected data was summarized and written in text format and in tables that contained: study design, patient' population, sample size, statistical significance and results of the intervention. The paper will cover malignancy, body composition, intervention with EPA, physiological mechanisms of action of EPA, effect of EPA on weight and body composition, future research. In cancer patients deterioration of muscle mass can be present regardless of body weight or Body Mass Index (BMI). Thus, sarcopenia in cancer patients with excessive fat mass (FM), entitled sarcopenic obesity, has gained greater relevance in clinical practice; it can negatively influence patients' functional status, tolerance to treatments & disease prognosis. The search for an effective nutritional intervention that improves body composition (preservation of muscle mass and muscle quality) is of utmost importance for clinicians and patients. The improvement of muscle quality is an even more recent area of interest because it has probable implications in patients' prognosis. Eicosapentaenoic acid (EPA) has been identified as a promising nutrient with the wide clinical benefits. Several mechanisms have been proposed to explain EPA potential benefits on body composition: inhibition of catabolic stimuli by modulating pro-inflammatory cytokines production and enhancing insulin sensitivity that induces protein synthesis; also, EPA may attenuate deterioration of nutritional status resulting from antineoplastic therapies by improving calorie and protein intake as well. Indeed

  18. EFFECTS OF WHOLE BODY VIBRATION ON STRENGTH AND JUMPING PERFORMANCE IN VOLLEYBALL AND BEACH VOLLEYBALL PLAYERS

    Science.gov (United States)

    Zmijewski, P.; Jimenez-Olmedo, J.M.; Jové-Tossi, M.A.; Martínez-Carbonell, A.; Suárez-Llorca, C.; Andreu-Cabrera, E.

    2014-01-01

    The primary aim of this study was to examine the effects of 6-week strength training with whole body vibration (WBV) on leg strength and jumping performance in volleyball and beach volleyball players. Twenty-three sub-elite male volleyball (VB; n=12) and beach volleyball players (BVB; n=11) aged 21.2±3.0 years were divided into two groups and subjected to 6 weeks of strength training (three one-hour sessions per week): (I) 12 players (6 VB and 6 BVB players) underwent training with WBV (30-40 Hz, 1.7-2.5 mm, 3.0-5.7 g), and (II) 11 players (6 VB and 5 BVB players) underwent traditional strength training. Squat jump (SJ) and countermovement squat jump (CMJ) measurements by the Ergo Tester contact platform and maximum leg press test (1RM) were conducted. Three-factor (2 time x 2 WBV use x 2 discipline) analysis of variance for SJ, CMJ and 1RM revealed a significant time main effect (pvolleyball and beach volleyball players increases leg strength more and leads to greater improvement in jump performance than traditional strength training, but greater improvements can be expected in beach volleyball players than in volleyball players. PMID:25187676

  19. Effects of bariatric surgery on the body composition of adults

    Directory of Open Access Journals (Sweden)

    Tiago Wally Hartwig

    2013-09-01

    Full Text Available The most alarming cases are known as morbidly obese. An effective method to change the anthropometric characteristics of this population with excess body weight and high fat mass is bariatric surgery. The objective of this study was to analyze the body composition of morbidly obese patients undergoing bariatric surgery in the city of Pelotas, Southern Brazil. In a prospective cohort study, a group of morbidly obese patients was followed up 30 days before and 30 days after surgery. The sample consisted of 123 patients who underwent vertical banded Roux-en-Y gastroplasty between April 2003 and May 2010. Body composition (fat percentage was determined by bioelectrical impedance analysis. The mean age of the patients was 36.1 ± 8.8 years and mean body weight loss was 14.1 ± 6.0 kg (p<0.001. The mean reduction in body mass index (BMI was 5.2 ± 2.1 kg/m2 (p<0.001. Body fat percentage and fat mass were reduced by 2.8% (p<0.001 and 9.7 ± 4.9 kg (p<0.001, respectively. In addition, there was a reduction of 4.4 ± 3.4 kg (p<0.001 in lean mass. We concluded that the surgical procedure significantly reduced body weight, BMI, fat percentage and fat mass and is an alternative when conventional treatments appear ineffective.

  20. Effect of Various Surface Treatment on Repair Strength of Composite Resin

    Directory of Open Access Journals (Sweden)

    Y. Alizade

    2004-12-01

    Full Text Available Statement of Problem: In some clinical situations, repair of composite restorations is treatment of choice. Improving the bond strength between one new and old composite usually requires increased surface roughness to promote mechanical interlocking sincechemical bonding might not be adequate. Similarly, the treatment of a laboratory fabricated resin composite restoration involves the same procedures, and there is a need to create the strongest possible bond of a resin cement to a previously polymerized composite.Purpose: The aim of this study was to evaluate the effect of various surface treatments on the shear bond strength of repaired to aged composite resin.Materials and Methods: Eighty four cylindrical specimens of a composite resin were fabricated and stored in distilled water for 100 days prior to surface treatment. Surface treatment of old composite was done in 6 groups as follow:1- Air abrasion with CoJet sand particles with micoretcher + silane + dentin bonding agent2- Air abrasion with 50μm Al2O3 particles+ phosphoric acid+ silane+ dentin bonding agent3- Air abrasion with 50μm Al2O3 particles + phosphoric acid + dentin bonding agent4- Diamond bur + phosphoric acid + silane + dentin bonding agent5- Diamond bur + phosphoric acid + dentin bonding agent6- Diamond bur + phosphoric acid + composite activator + dentin bonding agentThen fresh composite resin was bonded to treated surfaces. Twelve specimens were also fabricated as control group with the same diameter but with the height twice as much as other specimens. All of the specimens were thermocycled prior to testing for shear bondstrength. The bond strength data were analyzed statistically using one way ANOVA test, t test and Duncan's grouping test.Results: One-way ANOVA indicated no significant difference between 7 groups (P=0.059. One-way ANOVA indicated significant difference between the three diamond bur groups (P=0.036. Silane had a significant effect on the repair bond

  1. Effect of gas release in hot molding on flexural strength of composite friction brake

    Science.gov (United States)

    Rusdja, Andy Permana; Surojo, Eko; Muhayat, Nurul; Raharjo, Wijang Wisnu

    2018-02-01

    Composite friction brake is a vital part of braking system which serves to reduce the speed of vehicle. To fulfill the requirement of brake performance, composite friction brake must have friction and mechanical characteristic as required. The characteristics of composite friction brake are affected by brake material formulation and manufacturing parameter. In the beginning of hot molding, intermittent hot pressing was carried out to release the gases that consist of ammonia gas and water vapor. In composite friction brake, phenolic resin containing hexamethylenetetramine (HMTA) is often used as a binder. During hot molding, the reaction of phenolic resin and HMTA forms ammonia gas. Hot molding also generates water vapor because raw materials absorb moisture from environment when they are placed in storage. The gas release in hot molding is supposed affecting mechanical properties because it avoid entrapped gas in composite, so that this research investigated effect of gas release on flexural strength. Manufacturing of composite specimen was carried out as follow: mixing of raw materials, cold molding, and hot molding. In this research, duration of intermittent hot pressing and number of gas release were varied. The flexural strength of specimen was measured using three point bending test. The results showed that flexural strength specimens that were manufactured without gas release, using 4 times gas release with intermittent hot pressing for 5 and 10 seconds were not remarkably different. Conversely, hot molding using 4 times gas release with intermittent hot pressing for 15 seconds decreased flexural strength of composite. Hot molding using 2, 4, and 8 times gas release with intermittent hot pressing for 10 seconds also had no effect on increasing flexural strength. Increasing of flexural strength of composite was obtained only by using 6 times gas release with intermittent hot pressing for 10 seconds.

  2. Ultrastructural Analysis and Long-term Evaluation of Composite-Zirconia Bond Strength.

    Science.gov (United States)

    Aboushelib, Moustafa N; Ragab, Hala; Arnaot, Mohamed

    2018-01-01

    To evaluate the influence of different aging techniques on zirconia-composite microtensile bond strength using different surface treatments over a 5-year follow-up period. Zirconia disks received three surface treatments: airborne-particle abrasion with 50-μm aluminum oxide particles, selective infiltration etching (SIE), or fusion sputtering (FS). The specimens were bonded to pre-aged composite disks using a composite cement containing phosphate monomers (Panavia F2.0). Bonded specimens were sectioned into microbars (1 x 1 x 6 mm) using a precision cutting machine, and all microbars received thermocycling (15,000 cycles between 5°C and 55°C). Initial microtensile bond strength was evaluated, and the test was repeated after storage in the following media for five years (artificial saliva, 20% ethanol, 5% NaOH, 4% acetic acid, and 5% phosphoric acid). The test was repeated every 12 months for 5 years. Scanning electron microscopic images were used to analyze the zirconia-composite interface. A repeated measures ANOVA and Bonferroni post-hoc tests were used to analyze the data (n = 20, α = 0.05). Significantly higher microtensile bond strength was observed for SIE compared to fusion sputtering and airborne particle abrasion. Five years of artificial aging resulted in significant reduction of zirconia-composite bond strength for all tested specimens. Zirconia-composite bond strength was more sensitive to storage in sodium hydroxide and phosphoric acid, while it was least affected when stored under saliva. These changes were related to the mechanism of ultra-structural interaction between surface treatment and adhesive, as deterioration of the hybrid layer (composite-infiltrated ceramic) was responsible for bond degeneration. Zirconia-composite bond strength was influenced by 5 years of artificial aging.

  3. Basal metabolic rate and body composition of elite Japanese male athletes.

    Science.gov (United States)

    Koshimizu, Takako; Matsushima, Yoshiko; Yokota, Yukari; Yanagisawa, Kae; Nagai, Satsuki; Okamura, Koji; Komatsu, Yutaka; Kawahara, Takashi

    2012-01-01

    The estimated energy requirement is important for adequate nutritional management in athletes. The energy requirement can be estimated from the basal metabolic rate (BMR). However, there is little data regarding the BMR of Japanese athletes. This study measured the BMR and body composition of 81 elite Japanese male athletes in different sports categories: endurance (E), strength, power and sprint (S) and ball game (B). The factors influencing the BMR were also investigated. The BMR and body composition were measured by indirect calorimetry and an air-displacement plentysmograph device (the BOD POD), respectively. The BMR per lean body mass (LBM) differed significantly among the three groups. The BMR was significantly correlated with the body weight (BW) and LBM in all groups. A multiple-regression analysis showed that the LBM was the most powerful predictor in the E and S groups, whereas the BW was the most powerful predictor in the B group. The BW appears to become an important predictor as the BW of athletes increases. Additionally, height was the second explanatory variable in the S and B groups, thus suggesting that height needs to be considered for the BMR in these groups. Therefore, the BMR in elite athletes needs to be estimated according to their body composition.

  4. Radiographic analysis of body composition by computerized axial tomography

    International Nuclear Information System (INIS)

    Heymsfield, S.B.

    1986-01-01

    Radiographic methods of evaluating body composition have been applied for over five decades. A marked improvement in this approach occurred in the mid-nineteen-seventies with the introduction of computerized axial tomography. High image contrast, cross-sectional imaging and rapid computerized data processing make this technique a sophisticated clinically applicable tool. (author)

  5. Influence of orlistat on bone turnover and body composition

    DEFF Research Database (Denmark)

    Gotfredsen, A; Westergren Hendel, H; Andersen, T

    2001-01-01

    of bone mineral and body composition included total bone mineral content (TBMC), total bone mineral density (TBMD), lumbar spine BMC and BMD, forearm BMC and BMD, fat mass (FM), fat free-mass (FFM), percentage fat mass (FM%) as well as a DXA estimate of the body weight. Body composition (FM, FFM and FM....../creatinine and Ca/creatinine (fU-OHpr/creat, fUCa/creat). RESULTS: There were no significant differences between OLS and placebo groups as to any of the body composition variables (FFM, FM, FM%) at baseline or after 1 y treatment. Weight loss was of 11.2+/-7.5 kg in the OLS group and 8.1+/-7.5 kg in the placebo...... group (NS). The changes in FM and FM% were significant in both groups determined by DXA as well as by TBK, but the group differences between these changes were not significant. The composition of the weight loss was approximately 80% fat in both groups. FFM only changed significantly by DXA in the OLS...

  6. Changes in body composition and other anthropometric measures ...

    African Journals Online (AJOL)

    Background and objectives. An understanding of the effect of highly active antiretroviral therapy (HAART) on various aspects of health, including nutritional status, is needed to ensure that population-specific guidelines can be developed for South Africa. This study aimed to investigate the changes in body composition and ...

  7. The association between leptin, body composition and physical ...

    African Journals Online (AJOL)

    This study investigated the association between leptin, body composition and physical fitness in black adolescents from two selected schools in Ikageng, in the North West Province of South Africa. Baseline measurements were obtained from 124 boys and 148 girls between the ages of 13 and 20 years, which participated in ...

  8. Effect of Spinning Cycling Training on Body Composition in Women

    Science.gov (United States)

    Kaya, Fatih; Nar, Dilek; Erzeybek, Mustafa Said

    2018-01-01

    In this study the effects of a 6 week spinning cycling training on the body composition of women were investigated. Twelve sedentary women (32-47 years old) voluntarily participated in this study. The 6-week training program consisted of exercise sessions on 3 days per week. The intensity of the training program that was kept low in the beginning…

  9. Feed intake, live mass-gain, body composition and protein ...

    African Journals Online (AJOL)

    Feed intake, live mass-gain, body composition and protein deposition in pigs fed three protein levels. E.H. Kemm,* F.K. Siebrits, M.N. Ras and H.A. Badenhorst. Animal and Dairy Science Research Institute, Private Bag X2, Irene 1675, Republic of South Africa. A group of 82 genetically lean and 90 obese Landrace pigs was ...

  10. Voluntary feed intake, body composition and efficiency of two Merino ...

    African Journals Online (AJOL)

    individually on a diet with a metabolizable energy content of 10,26 MJ/kg. Measurements were made continuously of livemass, voluntary intake and body composition wsing tritium dilution. The growth results were analysed and interpreted relative to percentage of mature mass to account for differences in size. The intake of ...

  11. Flexural strength and modulus of elasticity of different types of resin-based composites.

    Science.gov (United States)

    Rodrigues Junior, Sinval Adalberto; Zanchi, Cesar Henrique; Carvalho, Rodrigo Varella de; Demarco, Flávio Fernando

    2007-01-01

    The aim of the study was to test whether the filler composition of resin composites influences their flexural strength and modulus of elasticity. Flexural strength and modulus of elasticity were obtained through a three-point bending test. Twelve bar shaped specimens of 5 commercially available composites--Supreme (3M/ESPE), a universal nanofilled composite; Esthet-X (Dentsply), Z-250 (3M/ESPE), Charisma (Heraeus Kulzer), universal hybrid composites; and Helio Fill (Vigodent), a microfine composite--were confectioned according to the ISO 4049/2000 specifications. The test was performed after a 7-days storage time using a universal test machine with a crosshead speed of 1 mm/min. The filler weight content was determined by the ashing technique. The data obtained on the mechanical properties were submitted to ANOVA and Tukey test (p elasticity results were observed among the universal hybrid composites. The nanofilled composite presented intermediary results. Within the limitations of this in vitro study, it could be concluded that the filler content significantly interfered in the flexural strength and modulus of elasticity of the composites tested.

  12. Push-Out Bond Strength of Restorations with Bulk-Fill, Flow, and Conventional Resin Composites

    Directory of Open Access Journals (Sweden)

    Rodrigo Vieira Caixeta

    2015-01-01

    Full Text Available The aim of this study was to evaluate the bond strengths of composite restorations made with different filler amounts and resin composites that were photoactivated using a light-emitting diode (LED. Thirty bovine incisors were selected, and a conical cavity was prepared in the facial surface of each tooth. All preparations were etched with Scotchbond Etching Gel, the Adper Scotchbond Multipurpose Plus adhesive system was applied followed by photoactivation, and the cavities were filled with a single increment of Filtek Z350 XT, Filtek Z350 XT Flow, or bulk-fill X-tra fil resin composite (n = 10 followed by photoactivation. A push-out test to determine bond strength was conducted using a universal testing machine. Data (MPa were submitted to Student’s t-test at a 5% significance level. After the test, the fractured specimens were examined using an optical microscope under magnification (10x. Although all three composites demonstrated a high prevalence of adhesive failures, the bond strength values of the different resin composites photoactivated by LED showed that the X-tra fil resin composite had a lower bond strength than the Filtek Z350 XT and Filtek Z350 XT Flow resin composites.

  13. Body composition in men with anorexia nervosa: Longitudinal study.

    Science.gov (United States)

    El Ghoch, Marwan; Calugi, Simona; Milanese, Chiara; Bazzani, Paola Vittoria; Dalle Grave, Riccardo

    2017-07-01

    To compare body composition patterns before and after complete weight restoration in men with anorexia nervosa. Dual-energy X-ray absorptiometry (DXA) was used to measure body composition patterns in 10 men with anorexia nervosa before and after complete weight restoration, and in 10 healthy men matched to age and patients' post-treatment body mass index (BMI). Before weight restoration, men with anorexia nervosa displayed lower total body fat mass (FM) and lean mass (LBM) than those in the healthy comparison group, with a greater FM loss from the extremity than the trunk region. After short-term weight restoration, patients displayed complete normalization in total LBM and FM, but greater deposition of FM in the trunk region. Short-term weight restoration can normalize body composition patterns in men with anorexia nervosa, but results in a central adiposity phenotype. The clinical implication of this finding is unknown, but should be explored given the high levels of concern about central adiposity in anorexia nervosa. © 2017 Wiley Periodicals, Inc.

  14. Effect of whole body vibration exercise on muscle strength and proprioception in females with knee osteoarthritis

    DEFF Research Database (Denmark)

    Trans, T; Aaboe, J; Henriksen, M

    2009-01-01

    status was measured using WOMAC. It was found that muscle strength increased significantly (pIsometric knee-extension significantly increased (p=0.021) in VibM compared to Con. TDPM was significantly improved (p=0.033) in VibF compared to Con, while there was a tendency......The purpose of this study was to assess the effect of whole body vibration (WBV) exercise on muscle strength and proprioception in female patients with osteoarthritis in the knee (knee-OA). A single blinded, randomised, controlled trial was performed in an outpatient clinic on 52 female patients...... groups trained twice a week for 8 weeks, with a progressively increasing intensity. The WBV groups performed unloaded static WBV exercise. The following were measured: knee muscle strength (extension/flexion) and proprioception (threshold for detection of passive movement (TDPM)). Self-reported disease...

  15. Comparison of Open-Hole Compression Strength and Compression After Impact Strength on Carbon Fiber/Epoxy Laminates for the Ares I Composite Interstage

    Science.gov (United States)

    Hodge, Andrew J.; Nettles, Alan T.; Jackson, Justin R.

    2011-01-01

    Notched (open hole) composite laminates were tested in compression. The effect on strength of various sizes of through holes was examined. Results were compared to the average stress criterion model. Additionally, laminated sandwich structures were damaged from low-velocity impact with various impact energy levels and different impactor geometries. The compression strength relative to damage size was compared to the notched compression result strength. Open-hole compression strength was found to provide a reasonable bound on compression after impact.

  16. Obesity paradox in cancer: new insights provided by body composition.

    Science.gov (United States)

    Gonzalez, Maria Cristina; Pastore, Carla A; Orlandi, Silvana P; Heymsfield, Steven B

    2014-05-01

    Obesity, defined by body mass index (BMI), appears to have a paradoxical protective effect in several chronic diseases. We investigated the obesity paradox in cancer patients by using body composition. The study was an observational study of 175 cancer patients assessed before chemotherapy. Obesity was defined as BMI (in kg/m(2)) ≥30 or fat mass index (FMI; fat mass divided by the square of height) ≥5.2 (men) and ≥8.2 (women) measured by using a bioelectrical impedance analysis. Low muscle mass (sarcopenia) was defined as fat-free mass index (fat-free mass divided by the square of height) cancer patients only when obesity is defined by BMI. Patients with sarcopenic obesity had the poorest prognosis. Cancer patients with high mortality risk can be identified by a body-composition assessment.

  17. Research on the compressive strength of basic magnesium salts and cyanide slag solidified body

    Science.gov (United States)

    Tu, Yubo; Han, Peiwei; Ye, Shufeng; Wei, Lianqi; Zhang, Xiaomeng; Fu, Guoyan; Yu, Bo

    2018-02-01

    The solidification of cyanide slag by using basic magnesium salts could reduce pollution and protect the environment. Experiments were carried out to investigate the effects of age, mixing amount of cyanide slag, water cement ratio and molar ratio of MgO to MgSO4 on the compressive strength of basic magnesium salts and cyanide slag solidified body in the present paper. It was found that compressive strength of solidified body increased with the increase of age, and decreased with the increase of mixing amount of cyanide slag and water cement ratio. The molar ratio of MgO to MgSO4 should be controlled in the range from 9 to 11 when the mixing amount of cyanide slag was larger than 80 mass%.

  18. Acute effect of passive static stretching on lower-body strength in moderately trained men.

    Science.gov (United States)

    Gergley, Jeffrey C

    2013-04-01

    The purpose of this investigation was conducted to determine the acute effect of passive static stretching (PSS) of the lower-body musculature on lower-body strength in a 1 repetition maximum (1RM) squat exercise in young (18-24 years.) moderately trained men (n = 17). Two supervised warm-up treatments were applied before each performance testing session using a counterbalanced design on nonconsecutive days. The first treatment consisted of an active dynamic warm-up (AD) with resistance machines (i.e., leg extension/leg flexion) and free weights (i.e., barbell squat), whereas the second treatment added PSS of the lower body plus the AD treatment. One repetition maximum was determined using the maximum barbell squat following a progressive loading protocol. Subjects were also asked to subjectively evaluate their lower-body stability during 1RM testing sessions for both the AD and PSS treatments. A significant decrease in 1RM (8.36%) and lower-body stability (22.68%) was observed after the PSS treatment. Plausible explanations for this observation may be related to a more compliant muscle tendon unit and/or altered or impaired neurologic function in the active musculature. It is also possible that strength was impaired by the PSS because of joint instability. The findings of this study suggest that intensive stretching such as lower-body PSS should be avoided before training the lower body or performing the 1RM in the squat exercise in favor of an AD dynamic warm-up using resistance training equipment in the lower-body musculature.

  19. Repair Strength in Simulated Restorations of Methacrylate- or Silorane-Based Composite Resins.

    Science.gov (United States)

    Consani, Rafael Leonardo Xediek; Marinho, Tatiane; Bacchi, Atais; Caldas, Ricardo Armini; Feitosa, Victor Pinheiro; Pfeifer, Carmem Silvia

    2016-01-01

    The study verified the bond strength in simulated dental restorations of silorane- or methacrylate-based composites repaired with methacrylate-based composite. Methacrylate- (P60) or silorane-based (P90) composites were used associated with adhesive (Adper Single Bond 2). Twenty-four hemi-hourglass-shaped samples were repaired with each composite (n=12). Samples were divided according to groups: G1= P60 + Adper Single Bond 2+ P60; G2= P60 + Adper Single Bond 2 + P60 + thermocycling; G3= P90 + Adper Single Bond 2 + P60; and G4= P90 + Adper Single Bond 2 + P60 + thermocycling. G1 and G3 were submitted to tensile test 24 h after repair procedure, and G2 and G4 after submitted to 5,000 thermocycles at 5 and 55 ?#61616;C for 30 s in each bath. Tensile bond strength test was accomplished in an universal testing machine at crosshead speed of 0.5 mm/min. Data (MPa) were analyzed by two-way ANOVA and Tukey's test (5%). Sample failure pattern (adhesive, cohesive in resin or mixed) was evaluated by stereomicroscope at 30?#61655; and images were obtained in SEM. Bond strength values of methacrylate-based composite samples repaired with methacrylate-based composite (G1 and G2) were greater than for silorane-based samples (G3 and G4). Thermocycling decreased the bond strength values for both composites. All groups showed predominance of adhesive failures and no cohesive failure in composite resin was observed. In conclusion, higher bond strength values were observed in methacrylate-based resin samples and greater percentage of adhesive failures in silorane-based resin samples, both composites repaired with methacrylate-based resin.

  20. Dietary strategies and body composition in elite weightlifting: Systematic Review

    Directory of Open Access Journals (Sweden)

    Alejandro Martínez-Rodríguez

    2017-10-01

    Full Text Available Introduction: There is little literature that showed the nutritional bases to optimize weightlifting performance. The objective was to perform a systematic review of the body composition and nutritional composition of diets in elite weightlifting athletes. Material and Methods: Articles published in Pubmed, Web of Science and Sport Discuss were reviewed following PRISMA Statement. The process for selecting studies was performed duplicated by two researchers in two stages (screening and application of eligibility criteria. A qualitative synthesis of the main characteristics and findings was made. The quality of studies was assessed. Results: Of the 610 articles found, 8 met the inclusion criteria, which were the studies performed in elite or high-level menopausal women, and information on dietary habits and/or body composition. Body composition identified that the percentage of fat mass was around 15%. A caloric intake of 4080.65±1602.69kcal, a protein intake of 17.29±3.2% of total daily energy (TDE, 42.48±5.6% TDE of carbohydrates and a 36.1±9.75% TDE of fats. A suboptimal dietary profile is suggested, showing an excess in fat intake, which could explain the excess body fat observed in some. Athletes’ protein intake and carbohydrates were within the recommended ranges except for 2 studies. Conclusions: An incorrect diet on the part of the elite weightlifting athletes was observed, which could condition their body composition negatively. The need for advice and intervention by a dietitian-nutritionist professionals was observed.

  1. A bedside measure of body composition in Duchenne muscular dystrophy.

    Science.gov (United States)

    Elliott, Sarah A; Davidson, Zoe E; Davies, Peter S W; Truby, Helen

    2015-01-01

    In clinical practice, monitoring body composition is a critical component of nutritional assessment and weight management in boys with Duchenne muscular dystrophy. We aimed to evaluate the accuracy of a simple bedside measurement tool for body composition, namely bioelectrical impedance analysis, in boys with Duchenne muscular dystrophy. Measures of fat-free mass were determined using a bioelectrical impedance analysis machine and compared against estimations obtained from a reference body composition model. Additionally, the use of raw impedance values was analyzed using three existing predictive equations for the estimation of fat-free mass. Accuracy of bioelectrical impedance analysis was assessed by comparison against the reference model by calculation of biases and limits of agreement. Body composition was measured in 10 boys with Duchenne muscular dystrophy, mean age 9.01 ± 2.34 years. The bioelectrical impedance analysis machine values of fat-free mass were on average 2.3 ± 14.1 kg higher than reference values. Limits of agreement (based on 95% confidence interval of the mean) were -7.4 to 2.9 kg. There was a significant correlation between the mean fat-free mass and difference in fat-free mass between the bioelectrical impedance analysis machine and the reference model (r = -0.86; P = 0.02) suggesting that the bias was not consistent across the range of measurements. The most accurate predictive equation for the estimation of fat-free mass using raw impedance values was the equation by Pietrobelli et al. (mean difference, -0.7 kg; 95% limits of agreement, -3.5 to 2.0 kg). In a clinical setting, where a rapid assessment of body composition is advantageous, the use of raw impedance values, combined with the equation by Pietrobelli et al., is recommended for the accurate estimation of fat-free mass, in boys with Duchenne muscular dystrophy. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Assessment of Isometric Trunk Strength - The Relevance of Body Position and Relationship between Planes of Movement.

    Science.gov (United States)

    Kocjan, Andrej; Sarabon, Nejc

    2014-05-01

    The aim of the study was to assess the differences in maximal isometric trunk extension and flexion strength during standing, sitting and kneeling. Additionally, we were interested in correlations between the maximal strength in sagittal, frontal and transverse plane, measured in the sitting position. Sixty healthy subjects (24 male, 36 female; age 41.3 ± 15.1 yrs; body height 1.70 ± 0.09 m; body mass 72.7 ± 13.3 kg) performed maximal voluntary isometric contractions of the trunk flexor and extensor muscles in standing, sitting and kneeling position. The subjects also performed lateral flexions and rotations in the sitting position. Each task was repeated three times and average of maximal forces was used for data analysis. RANOVA with post-hoc testing was applied to the flexion and extension data. The level of statistical significance was set to p strength showed the strongest correlation, followed by frontal-transverse and sagittal-frontal plane correlation pairs (R(2) = 0.830, 0.712 and 0.657). The baseline trunk isometric strength data provided by this study should help further strength diagnostics, more precisely, the prevention of low back disorders. Key pointsMaximal voluntary isometric force of the trunk extensors increased with the angle at the hips (highest in sitting, medium in kneeling and lowest in upright standing).The opposite trend was true for isometric MVC force of trunk flexors (both genders together and men only).In the sitting position, the strongest correlation between MVC forces was found between sagittal (average flexion/extension) and transverse plane (average left/right rotation).IN ORDER TO INCREASE THE VALIDITY OF TRUNK STRENGTH TESTING THE LETTER SHOULD INCLUDE: specific warm-up, good pelvic fixation and visual feedback.

  3. Body Composition and Mortality Predictors in Hemodialysis Patients.

    Science.gov (United States)

    Caetano, Cristina; Valente, Ana; Oliveira, Telma; Garagarza, Cristina

    2016-03-01

    To evaluate how different compartments of body composition can affect survival in hemodialysis (HD) patients. Multicenter longitudinal observational study of a cohort of patients in HD with 12 months of follow-up. Patients from 34 Nephrocare dialysis units in Portugal were included. A total of 697 patients on maintenance HD during 4 hours 3 days per week were enrolled. Dry weight, presence of diabetes, body mass index (BMI), lean tissue index (LTI), fat tissue index (FTI), body cell mass index (BCMI), albumin and hydration status were recorded at baseline. In all patients, the assessment of body composition was carried out using the Body Composition Monitor (BCM; Fresenius Medical Care a Deutschland GmbH, Germany). Survival during a 12-month period of follow-up. Patient's mean (±standard deviation) age was 65.4 ± 14.3 years, and median (interquartile range) HD vintage was 41 (19-81) months. Patients who died during the study period, had higher age (P < .001), lower dry weight (P = .001), BMI (P < .001), albumin (P < .001), LTI (P = .015), and also lower BCMI (P = .046). Patients with diabetes (P = .045), BMI < 18.5 kg/m(2) (P < .001), albumin < 4.0 g/dL (P < .001), relative overhydration ≥ 15% (P = .001), low FTI (P = .019), and also those in the lowest tertile of BCMI (P = .022) displayed a significantly worse survival. In the Cox regression analysis, the overall mortality of patient was related to low FTI, relative overhydration, BMI < 18.5 kg/m(2), BCMI ≤ 5.2 kg/m(2), and albumin < 4.0 g/dL. Several body composition parameters demonstrated to have an important role in predicting 1-year mortality in HD patients. Albumin, FTI, and BMI were useful predictors of mortality in these patients. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  4. Endurance training intensity does not mediate interference to maximal lower-body strength gain during short-term concurrent training.

    Directory of Open Access Journals (Sweden)

    Jackson J Fyfe

    2016-11-01

    Full Text Available We determined the effect of concurrent training incorporating either high-intensity interval training (HIT or moderate-intensity continuous training (MICT on maximal strength, counter-movement jump (CMJ performance, and body composition adaptations, compared with single-mode resistance training (RT. Twenty-three recreationally-active males (mean ± SD: age, 29.6 ± 5.5 y; V ̇O 2peak, 44 ± 11 mL∙kg-1•min-1 were ranked by one-repetition maximum (1-RM leg press strength and randomly allocated tounderwent 8 weeks (3 sessions•wk-1 of either: 1 HIT combined with RT (HIT+RT group, n=8, 2 work-matched MICT combined with RT (MICT+RT group, n=7, or 3 RT performed alone (RT group, n=8. Measures of aerobic capacity, maximal (1-RM strength, counter-movement jump (CMJ performance and body composition (DXA were obtained before (PRE, mid-way (MID, and after (POST eight weeks of training. Maximal (one-repetition maximum [1-RM] leg press strength was improved from PRE to POST for RT (mean change ±90% confidence interval; 38.5 ±8.5%; effect size [ES] ±90% confidence interval; 1.26 ±0.24; P<0.001, HIT+RT (28.7 ±5.3%; ES, 1.17 ±0.19; P<0.001 and MICT+RT (27.5 ±4.6%, ES, 0.81 ±0.12; P<0.001; however, the magnitude of this change was greater for RT vs. both HIT+RT (7.4 ±8.7%; ES, 0.40 ±0.40 and MICT+RT (8.2 ±9.9%; ES, 0.60 ±0.45. There were no substantial between-group differences in 1-RM bench press strength gain. RT induced greater changes in peak CMJ force vs. HIT+RT (6.8 ±4.5%; ES, 0.41 ±0.28 and MICT+RT (9.9 ±11.2%; ES, 0.54 ±0.65, and greater improvements in maximal CMJ rate of force development (RFD vs. HIT+RT (24.1 ±26.1%; ES, 0.72 ±0.88. Lower-body lean mass was similarly increased for RT (4.1 ±2.0%; ES; 0.33 ±0.16; P=0.023 and MICT+RT (3.6 ±2.4%; ES; 0.45 ±0.30; P=0.052; however, this change was attenuated for HIT+RT (1.8 ±1.6%; ES; 0.13 ±0.12; P=0.069. We conclude that concurrent training incorporating either HIT or work

  5. [Body, strength, and labor: reflexions in the light of gender relations].

    Science.gov (United States)

    Costa, L H

    2000-01-01

    The present paper intends to contribute on a reflection and discussion of some issues related to female's body and the strength present in laborwork, understood as the moment in which through the support of another person, a woman "gives birth". It also discusses the perspective of male dominance having as reference the symbolic violence from Bordieu, proposing that the humanizing of labor demands a thorough discussion on gender dominance.

  6. Daily marathon running for a week-the biochemical and body compositional effects of participation

    DEFF Research Database (Denmark)

    Karstoft, Kristian; Solomon, Thomas; Laye, Matthew J

    2013-01-01

    Karstoft, K, Solomon, TP, Laye, MJ, and Pedersen, BK. Daily marathon running for a week-The biochemical and body compositional effects of participation. J Strength Cond Res 27(11): 2927-2933, 2013-Although long-distance running, such as ultramarathons and multistage races, is increasingly popular......, it maybe potentially harmful to health, despite sparse evidence. We studied 8 experienced recreational runners participating in a multiple-marathon running event in which 7 marathons were completed on consecutive days. Fasting blood chemistry and body composition were assessed before and 20-24 hours after...... the race. The total finish time for the 7 marathons ranged between 23:25:42 and 34:25:21 (hours:minutes:seconds). Only minor increases in circulating skeletal muscle cell damage markers, liver cell damage markers, and inflammatory markers occurred after the race. No other significant adverse biochemical...

  7. Influence of increment thickness on dentin bond strength and light transmission of composite base materials.

    Science.gov (United States)

    Omran, Tarek A; Garoushi, Sufyan; Abdulmajeed, Aous A; Lassila, Lippo V; Vallittu, Pekka K

    2017-06-01

    Bulk-fill resin composites (BFCs) are gaining popularity in restorative dentistry due to the reduced chair time and ease of application. This study aimed to evaluate the influence of increment thickness on dentin bond strength and light transmission of different BFCs and a new discontinuous fiber-reinforced composite. One hundred eighty extracted sound human molars were prepared for a shear bond strength (SBS) test. The teeth were divided into four groups (n = 45) according to the resin composite used: regular particulate filler resin composite: (1) G-ænial Anterior [GA] (control); bulk-fill resin composites: (2) Tetric EvoCeram Bulk Fill [TEBF] and (3) SDR; and discontinuous fiber-reinforced composite: (4) everX Posterior [EXP]. Each group was subdivided according to increment thickness (2, 4, and 6 mm). The irradiance power through the material of all groups/subgroups was quantified (MARC® Resin Calibrator; BlueLight Analytics Inc.). Data were analyzed using two-way ANOVA followed by Tukey's post hoc test. SBS and light irradiance decreased as the increment's height increased (p composite used. EXP presented the highest SBS in 2- and 4-mm-thick increments when compared to other composites, although the differences were not statistically significant (p > 0.05). Light irradiance mean values arranged in descending order were (p composites. Discontinuous fiber-reinforced composite showed the highest value of curing light transmission, which was also seen in improved bonding strength to the underlying dentin surface. Discontinuous fiber-reinforced composite can be applied safely in bulks of 4-mm increments same as other bulk-fill composites, although, in 2-mm thickness, the investigated composites showed better performance.

  8. A comparative effect of various surface chemical treatments on the resin composite-composite repair bond strength

    Directory of Open Access Journals (Sweden)

    Shaloo Gupta

    2015-01-01

    Full Text Available Aim: The aim of this in vitro study was an attempt to investigate the effect of different surface treatments on the bond strength between pre-existing composite and repair composite resin. Materials and Methods: Forty acrylic blocks were prepared in a cuboidal mould. In each block, a well of 5 mm diameter and 5 mm depth was prepared to retain the composite resin (Filtek™ Z350, 3M/ESPE. Aging of the composite discs was achieved by storing them in water at 37°C for 1 week, and after that were divided into 5 groups (n = 8 according to surface treatment: Group I- 37% phosphoric acid, Group II-10% hydrofluoric acid, Group III-30% citric acid, Group IV-7% maleic acid and Group V- Adhesive (no etchant. The etched surfaces were rinsed and dried followed by application of bonding agent (Adper™ Single Bond 2. 3M/ESPE. The repair composite was placed on aged composite, light-cured for 40 seconds and stored in water at 37°C for 1 week. Shear bond strength between the aged and the new composite resin was determined with a universal testing machine (crosshead speed of 0.5 mm/min. Statistical Analysis: The compressive shear strengths were compared for differences using ANOVA test followed by Tamhane′s T2 post hoc analysis. Results: The surface treatment with 10% hydrofluoric acid showed the maximum bond strength followed by 30% citric acid, 7% maleic acid and 37% phosphoric acid in decreasing order. Conclusion: The use of 10% hydrofluoric acid can be a good alternative for surface treatment in repair of composite resin restoration as compared to commonly used 37% orthophosphoric acid.

  9. The influence of double nested layer waviness on compression strength of carbon fiber composite materials

    International Nuclear Information System (INIS)

    Khan, Z.M.

    1997-01-01

    As advanced composite materials having superior physical and mechanical properties are being developed, optimization of their production processes in eagerly being sought. One of the most common defect in production of structural composites is layer waviness. Layer waviness is more pronounced in thick section flat and cylindrical laminates that are extensively used in missile casings, submersibles and space platforms. Layer waviness undulates the entire layers of a multidirectional laminate in through-the-thickness direction leading to gross deterioration of its compression strength. This research investigates the influence of multiple layer waviness in a double nest formation on the compression strength of a composite laminate. Different wave fractions of wave 0 degree centigrade layer fabricated in IM/85510-7 carbon - epoxy composite laminate on a steel mold using single step fabrication procedure. The laminate was cured on a heated press according to specific curing cycle. Static compression testing was performed using NASA short block compression fixture on an MTS servo Hydraulic machine. The purpose of these tests was to determine the effects of multiple layer wave regions on the compression strength of composite laminate. The experimental and analytical results revealed that up to about 35% fraction of wave 0 degree layer exceeded 35%. This analysis indicated that the percentage of 0 degree wavy layer may be used to estimate the reduction in compression strength of a composite laminate under restricted conditions. (author)

  10. Body Composition Response to Lower Body Positive Pressure Training in Obese Children

    OpenAIRE

    Basant H. El-Refay; Nabeel T. Faiad

    2014-01-01

    Background: The high prevalence of obesity in Egypt has a great impact on the health care system, economic and social situation. Evidence suggests that even a moderate amount of weight loss can be useful. Aim of the study: To analyze the effects of lower body positive pressure supported treadmill training, conducted with hypocaloric diet, on body composition of obese children. Methods: Thirty children aged between 8 and 14 years, were randomly assigned into two groups: intervention group (15 ...

  11. Studying Hardness Meter Spring Strength to Understand Hardness Distribution on Body Surfaces.

    Science.gov (United States)

    Arima, Yoshitaka

    2017-10-01

    For developing a hardness multipoint measurement system for understanding hardness distribution on biological body surfaces, we investigated the spring strength of the contact portion main axis of a biological tissue hardness meter (product name: PEK). We measured the hardness of three-layered sheets of six types of gel sheets (90 mm × 60 mm × 6 mm) constituting the acupuncture practice pads, with PEK measurements of 1.96 N, 2.94 N, 3.92 N, 4.90 N, 5.88 N, 6.86 N, 7.84 N, 8.82 N, and 9.81 N of the main axis spring strength. We obtained measurements 10 times for the gel sheets and simultaneously measured the load using a digital scale. We measured the hardness distribution of induration embedded and breast cancer palpation models, with a main axis with 1.96 N, 4.90 N, and 9.81 N spring strengths, to create a two-dimensional Contour Fill Chart. Using 4.90 N spring strength, we could obtain measurement loads of ≤3.0 N, and the mean hardness was 5.14 mm. This was close to the median of the total measurement range 0.0-10.0 mm, making the measurement range the largest for this spring strength. We could image the induration of the induration-embedded model regardless of the spring strength. Overall, 4.90 N spring strength was best suited for imaging cancer in the breast cancer palpation model. Copyright © 2017. Published by Elsevier B.V.

  12. Dentin-Composite Bond Strength Measurement Using the Brazilian Disk Test

    Science.gov (United States)

    Carrera, Carola A.; Chen, Yung-Chung; Li, Yuping; Rudney, Joel; Aparicio, Conrado; Fok, Alex

    2016-01-01

    Objectives This study presents a variant of the Brazilian disk test (BDT) for assessing the bond strength between composite resins and dentin. Methods Dentin-composite disks (φ 5 mm × 2 mm) were prepared using either Z100 or Z250 (3M ESPE) in combination with one of three adhesives, Adper Easy Bond (EB), Adper Scotchbond Multi-Purpose (MP) and Adper Single Bond (SB), and tested under diametral compression. Acoustic emission (AE) and digital image correlation (DIC) were used to monitor debonding of the composite from the dentin ring. A finite element (FE) model was created to calculate the bond strengths using the failure loads. Fracture modes were examined by scanning electron microscopy (SEM). Results Most specimens fractured along the dentin-resin composite interface. DIC and AE confirmed interfacial debonding immediately before fracture of the dentin ring. Results showed that the mean bond strength with EB (14.9±1.9 MPa) was significantly higher than with MP (13.2±2.4 MPa) or SB (12.9±3.0 MPa) (p0.05). Z100 (14.5±2.3 MPa) showed higher bond strength than Z250 (12.7±2.5 MPa) (padhesive failure mode. EB failed mostly at the dentin-adhesive interface, whereas MP at the composite-adhesive interface; specimens with SB failed at the composite-adhesive interface and cohesively in the adhesive. Conclusions The BDT variant showed to be a suitable alternative for measuring the bond strength between dentin and composite, with zero premature failure, reduced variability in the measurements, and consistent failure at the dentin-composite interface. PMID:27395367

  13. DEVELOPMENT AND VALIDATION OF NUMERICAL METHOD FOR STRENGTH ANALYSIS OF LATTICE COMPOSITE FUSELAGE STRUCTURES

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available Lattice composite fuselage structures are developed as an alternative to conventional composite structures based on laminated skin and stiffeners. Structure layout of lattice structures allows to realize advantages of current composite materials to a maximal extent, at the same time minimizing their main shortcomings, that allows to provide higher weight efficiency for these structures in comparison with conventional analogues.Development and creation of lattice composite structures requires development of novel methods of strength anal- ysis, as conventional methods, as a rule, are aiming to strength analysis of thin-walled elements and do not allow to get confident estimation of local strength of high-loaded unidirectional composite ribs.In the present work the method of operative strength analysis of lattice composite structure is presented, based onspecialized FE-models of unidirectional composite ribs and their intersections. In the frames of the method, every rib is modeled by a caisson structure, consisting of arbitrary number of flanges and webs, modeled by membrane finite elements. Parameters of flanges and webs are calculated automatically from the condition of stiffness characteristics equality of real rib and the model. This method allows to perform local strength analysis of high-loaded ribs of lattice structure without use of here-dimensional finite elements, that allows to shorten time of calculations and sufficiently simplify the procedure of analysis of results of calculations.For validation of the suggested method, the results of experimental investigations of full-scale prototype of shell of lattice composite fuselage section have been used. The prototype of the lattice section was manufactured in CRISM and tested in TsAGI within the frames of a number of Russian and International scientific projects. The results of validation have shown that the suggested method allows to provide high operability of strength analysis, keeping

  14. Strength analysis of aged polymer composites subjected to tensile loads

    Science.gov (United States)

    Valesyan, S.

    2018-04-01

    It follows from the obtained data that the change of durability of the getinacks in stretching significantly depends on the pressing pressure value both at the age of 1 year and at the age of 4 years. According to the data, in the case of samples of the first series, the ageing has not practically affected the durability of getinacks in stretching. In the case of samples of other series, the increase of age from 1 year to 4 years results in an increase of the getinacks durability, in particular, the increase is about 9% for the third series. Comparing the values of failure tensile stresses given in the handbook of electrotechnics materials [1] with the data obtained by experimental investigation of aged glass textolite (GFRP composite-laminate) with the woven fiber orientation 0° and 90°, one can see a corresponding increase by approximately 25% and 35%. The test results are approximated and compared with the experimental data. The corresponding figures are plotted on the basis of these data.

  15. Yield strengths of tungsten-base composites determined from bend tests

    International Nuclear Information System (INIS)

    Zukas, E.G.; Eash, D.T.

    1976-08-01

    The variation in yield strength with either strain rate or temperature was determined for a number of tungsten-base composites by use of the simple three-point bend test. The yield strengths were comparable with those obtained in standard tensile tests. Additional studies on 1019 steel, either in the as-rolled or annealed condition, gave results in agreement with handbook values, as did two aluminum alloys. These results demonstrate that the bend test deserves wider acceptance in materials testing programs

  16. THE BIODEGRADABILITY AND MECHANICAL STRENGTH OF NUTRITIVE POTS FOR VEGETABLE PLANTING BASED ON LIGNOCELLULOSE COMPOSITE MATERIALS

    OpenAIRE

    Petronela Nechita; Elena Dobrin; Florin Ciolacu; Elena Bobu

    2010-01-01

    Considering the mild degradation strength and the fact that it may be an organic matter reserve for the soil, in the past years lignocellulosic materials have been used as fibrous raw materials in the manufacture of biodegradable nutritive pots for the seedling in vegetable containerized production. This paper analyses the behavior of the nutritive pots made from biodegradable composites for the vegetable seedling production process, focusing on their mechanical strength properties and biodeg...

  17. Shear bond strength between an indirect composite layering material and feldspathic porcelain-coated zirconia ceramics.

    Science.gov (United States)

    Fushiki, Ryosuke; Komine, Futoshi; Blatz, Markus B; Koizuka, Mai; Taguchi, Kohei; Matsumura, Hideo

    2012-10-01

    This study aims to evaluate the effect of both feldspathic porcelain coating of zirconia frameworks and priming agents on shear bond strength between an indirect composite material and zirconia frameworks. A total of 462 airborne-particle-abraded zirconia disks were divided into three groups: untreated disks (ZR-AB), airborne-particle-abraded zirconia disks coated with feldspathic porcelain, (ZR-PO-AB), and hydrofluoric acid-etched zirconia disks coated with feldspathic porcelain (ZR-PO-HF). Indirect composite (Estenia C&B) was bonded to zirconia specimens with no (CON) or one of four priming agents--Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + activator), Estenia Opaque primer, or Porcelain Liner M Liquid B (PLB)--with or without an opaque material (Estenia C&B Opaque). All specimens were tested for shear bond strength before and after 20,000 thermocycles. The Steel-Dwass test and Mann-Whitney U test were used to compare shear bond strength. In ZR-AB specimens, the initial bond strength of the CPB and CPB + Activator groups was significantly higher as compared with the other three groups (P material, bond strength was significantly lower in ZR-AB specimens than in ZR-PO-AB and ZR-PO-HF specimens (P composite to zirconia independent of surface treatment. The use of a silane coupling agent and opaque material yields durable bond strength between the indirect composite and feldspathic-porcelain-coated zirconia. The results of the present study suggest that feldspathic porcelain coating of zirconia frameworks is an effective method to obtain clinically acceptable bond strengths of a layering indirect composite material to a zirconia framework.

  18. Effects of whole-body vibration on muscle strength and power of elderly: A systematic review

    Directory of Open Access Journals (Sweden)

    Monique Opuszcka Campos

    2014-02-01

    Full Text Available The aim of this systematic review was to summarize available scientific evidence on the utilization of whole body vibration as an alternative method to promote effective modifications on muscle strength and power in the aging population.  Scientific studies were retrieved from the following databases: Medline, Scielo, Lillacs, Cochrane Library, PEDro and Science Citation Index. The PEDro scale was used to assess the quality of the included studies, while content went through a critical analysis. From the 91 studies retrieved, 75 were excluded and 16 attended the selection criteria. From the16, the majority (68.8% presented from moderate to high methodological quality. Whole-body vibration associated to both isometric and dynamic exercises seemed to constitute an alternative for therapeutic intervention to improve muscular strength and power of healthy elderly. However, due to the characteristics of the designs of the studies reviewed and the threats to their internal validity (i.e., the absence of the control condition to the vibratory stimulus it was challenging to establish the additional effects of the whole-body vibration on the target population. Divergent findings were found for the whole-body vibration effect on muscular power. It is still necessary to conduct randomized control trials to establish the real effectiveness of this kind of intervention.

  19. Effect of Exercise Type During Intentional Weight Loss on Body Composition in Older Adults with Obesity.

    Science.gov (United States)

    Beavers, Kristen M; Ambrosius, Walter T; Rejeski, W Jack; Burdette, Jonathan H; Walkup, Michael P; Sheedy, Jessica L; Nesbit, Beverly A; Gaukstern, Jill E; Nicklas, Barbara J; Marsh, Anthony P

    2017-11-01

    To examine the long-term effects of exercise modality during weight loss on body composition and associations between body composition and physical function changes. Two hundred forty-nine older adults (66.9 ± 4.7 years, 71% women, 32% African American, BMI: 34.4 ± 3.7 kg/m 2 ) were randomized to weight loss (WL; n = 82), WL plus aerobic training (WL + AT; n = 86), or WL plus resistance training (WL + RT; n = 81) for 18 months. Dual-energy x-ray absorptiometry-acquired body composition, 400-m walk time, and knee extensor strength were measured at baseline and at 6 and 18 months. Total body mass loss was enhanced when WL was combined with exercise (WL: -5.7 ± 0.7 kg, WL + AT: -8.5 ± 0.7 kg, WL + RT: -8.7 ± 0.7 kg; P exercise yields greater fat mass loss than WL alone. © 2017 The Obesity Society.

  20. Tracking of Body Composition in Pre-Adolescent Thai Children

    International Nuclear Information System (INIS)

    Thasanauwan, Wiyada; Kijboonchoo, Kallaya; Srichan, Weerachat; Judprasong, Kunchit; Wimonpeerapattana, Wanphen

    2014-01-01

    Full text: Background: Childhood obesity is one of the global malnutrition problem. To assess body composition, stable isotope has been widely used for total body water (TBW) and body fat assessments. In the year 2008, Thailand involved in the IAEA Technical Cooperation Project (TC project) which aimed to develop and validate tools for Thai children to assess obesity in 247 pre-adolescent children aged 8 to 10 years. Later in the year 2011, only 100 children were agreed to be tracked for their body composition assessment. Objective: To explore the changes of body composition and to compare the changes between gender in 3 years period. Materials and methods: A total of 100 children (49 boys and 51 girls), who involved the project in 2008 (P1) and later in 2011 (P2) were measured for their body composition. BMI for age using WHO 2007 cut off was used to identify their nutritional status. TBW was determined by deuterium oxide dilution technique. Fat-free mass (FFM) and fat mass (FM) were estimated. Results: Out of 100 children, 87 children (41 boys and 46 girls) provided the completed data of TBW at P1 and P2. They all grew up with significantly increased in weight, height, BMI (p<0.001). Their body composition in terms of %TBW, %FEM and %FM were not changed in both genders. Boys had significant higher %FFM than girls in P1 (71.5% in boys and 67.4% in girls, p<0.05) while %FM were significant lower than girls (28.5% in boys and 32.6% in girls, p<0.05). However, after 3 years, no significant different between boys and girls was observed. Over the 3 years period, based on BMI for age, the proportion of overweight and obese children increased from 36.6% to 48.8% for boys, and from 32.6% to 41.3% for girls. Around 17% of normal boys became overweight and obese, and for girls only 8.7% was found. Less than 5% of overweight and obese boys became normal, and none for girls. Conclusion: The obesity problem was inevitably increased when children are advance in age. However for

  1. Upper body push and pull strength ratio in recreationally active adults.

    Science.gov (United States)

    Negrete, Rodney J; Hanney, William J; Pabian, Patrick; Kolber, Morey J

    2013-04-01

    Agonist to antagonist strength data is commonly analyzed due to its association with injury and performance. The purpose of this study was to examine the agonist to antagonist ratio of upper body strength using two simple field tests (timed push up/timed modified pull up) in recreationally active adults and to establish the basis for reference standards. One hundred eighty (180) healthy recreationally active adults (111 females and 69 males, aged 18-45 years) performed two tests of upper body strength in random order: 1. Push-ups completed during 3 sets of 15 seconds with a 45 second rest period between each set and 2. Modified pull-ups completed during 3 sets of 15 seconds with a 45 second rest period between each set. The push-up to modified pull-up ratio for the males was 1.57:1, whereas females demonstrated a ratio of 2.72:1. The results suggest that for our group of healthy recreationally active subjects, the upper body "pushing" musculature is approximately 1.5-2.7 times stronger than the musculature involved for pulling. In this study, these recreationally active adults displayed greater strength during the timed push-ups than the modified pull-ups. The relationship of these imbalances to one's performance and or injury risk requires further investigation. The reference values, however, may serve the basis for future comparison and prospective investigations. The field tests in this study can be easily implemented by clinicians and an agonist/antagonist ratio can be determined and compared to our findings. 2b.

  2. In vitro/in silico investigation of failure criteria to predict flexural strength of composite resins.

    Science.gov (United States)

    Yamaguchi, Satoshi; Mehdawi, Idris Mohamed; Sakai, Takahiko; Abe, Tomohiro; Inoue, Sayuri; Imazato, Satoshi

    2018-01-30

    The aim of this study was to investigate a failure criterion to predict flexural strengths of composite resins (CR) by three-dimensional finite element analysis (3D-FEA). Models of flexural strength for test specimens of CR and rods comprising a three-point loading were designed. Calculation of Young's moduli and Poisson's ratios of CR were conducted using a modified McGee-McCullough model. Using the experimental CR, flexural strengths were measured by three-point bending tests with crosshead speed 1.0 mm/min and compared with the values determined by in silico analysis. The flexural strengths of experimental CR calculated using the maximum principal strain significantly correlated with those obtained in silico amongst the four types of failure criteria applied. The in silico analytical model established in this study was found to be effective to predict the flexural strengths of CR incorporating various silica filler contents by maximum principal strain.

  3. The association of body composition parameters with nonalcoholic hepatic steatosis

    Directory of Open Access Journals (Sweden)

    Mesut Sipahi

    2015-06-01

    Full Text Available Objective:Nonalcoholic fatty liver disease (NAFLD which is strongly correlated with obesity; has been a common worldwide health problem with the improvements in social status. Body composition studies are accepted as a simple follow-up tool for treatment of obesity. Since the correlation of body mass index (BMI with the hepatosteatosis (HS is well known; the aim of this study was to assess the usefulness of body composition parameters (BCP to determine HS on NAFLD patients; using dual bioimpedance analyzer (BIA. Methods:A total of 253 patients with diagnosis of NAFLD were included into the study. The demographic parameters such as age, sex and BMI were collected; and the ultrasonographic (US evolution was performed to determine the HS stages. The BCP, such as amount and the percentage of total body fat, fat free mass, and total body water were assessed with the dual bioimpedance analyzer. Results:There were strong significant correlations between BMI and HS, between BCP and HS (p0.05. Conclusion: According to our results, it can be concluded that BCP values may have a diagnostic value on diagnosis of NAFLD.

  4. Tests of the discretized-continuum method in three-body dipole strengths

    Energy Technology Data Exchange (ETDEWEB)

    Pinilla, E.C., E-mail: epinilla@ulb.ac.be [Physique Nucleaire Theorique et Physique Mathematique, C.P. 229, Universite Libre de Bruxelles (ULB), B 1050 Brussels (Belgium); Baye, D., E-mail: dbaye@ulb.ac.be [Physique Quantique, C.P. 165/82, Universite Libre de Bruxelles (ULB), B 1050 Brussels (Belgium); Physique Nucleaire Theorique et Physique Mathematique, C.P. 229, Universite Libre de Bruxelles (ULB), B 1050 Brussels (Belgium); Descouvemont, P., E-mail: pdesc@ulb.ac.be [Physique Nucleaire Theorique et Physique Mathematique, C.P. 229, Universite Libre de Bruxelles (ULB), B 1050 Brussels (Belgium); Horiuchi, W., E-mail: whoriuchi@riken.jp [RIKEN Nishina Center, Wako 351-0918 (Japan); Suzuki, Y., E-mail: suzuki@nt.sc.niigata-u.ac.jp [Department of Physics, Niigata University, Niigata 950-2181 (Japan); RIKEN Nishina Center, Wako 351-0918 (Japan)

    2011-08-15

    We investigate the {sup 6}He dipole distribution in a three-body {alpha}+n+n model. Two approaches are used to describe the three-body 1{sup -} continuum: the discretized-continuum method, where the scattering wave functions are approximated by square-integrable functions, and the R-matrix formalism, where their asymptotic behaviour is taken into account. We show that some ambiguity exists in the pseudostate method, owing to the smoothing technique, necessary to derive continuous distributions. We show evidence for the important role of the halo structure in the E1 dipole strength. We also address the treatment of Pauli forbidden states in the three-body wave functions.

  5. Influence of superconductor film composition on adhesion strength of coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Kesgin, Ibrahim; Khatri, Narayan; Liu, Yuhao; Delgado, Louis; Galstyan, Eduard; Selvamanickam, Venkat

    2015-11-20

    The effect of high temperature superconductor (HTS) film composition on the adhesion strength of rare- earth barium copper oxide coated conductors (CCs) has been studied. It has been found that the mechanical integrity of the superconductor layer is very susceptible to the defects especially those along the ab plane, probably due to the weak interfaces between the defects and the matrix. Gd and Y in the standard composition were substituted with Sm and the number of in-plane defects was drastically reduced. Consequently, a four-fold increase in adhesion or peeling strength in Sm-based CCs was achieved compared to the standard GdYBCO samples.

  6. Influence of superconductor film composition on adhesion strength of coated conductors

    International Nuclear Information System (INIS)

    Kesgin, Ibrahim; Khatri, Narayan; Liu, Yuhao; Delgado, Louis; Galstyan, Eduard; Selvamanickam, Venkat

    2016-01-01

    The effect of high temperature superconductor (HTS) film composition on the adhesion strength of rare-earth barium copper oxide coated conductors (CCs) has been studied. It has been found that the mechanical integrity of the superconductor layer is very susceptible to the defects especially those along the ab plane, probably due to the weak interfaces between the defects and the matrix. Gd and Y in the standard composition were substituted with Sm and the number of in-plane defects was drastically reduced. Consequently, a four-fold increase in adhesion or peeling strength in Sm-based CCs was achieved compared to the standard GdYBCO samples. (paper)

  7. The ancestral logic of politics: upper-body strength regulates men's assertion of self-interest over economic redistribution.

    Science.gov (United States)

    Petersen, Michael Bang; Sznycer, Daniel; Sell, Aaron; Cosmides, Leda; Tooby, John

    2013-07-01

    Over human evolutionary history, upper-body strength has been a major component of fighting ability. Evolutionary models of animal conflict predict that actors with greater fighting ability will more actively attempt to acquire or defend resources than less formidable contestants will. Here, we applied these models to political decision making about redistribution of income and wealth among modern humans. In studies conducted in Argentina, Denmark, and the United States, men with greater upper-body strength more strongly endorsed the self-beneficial position: Among men of lower socioeconomic status (SES), strength predicted increased support for redistribution; among men of higher SES, strength predicted increased opposition to redistribution. Because personal upper-body strength is irrelevant to payoffs from economic policies in modern mass democracies, the continuing role of strength suggests that modern political decision making is shaped by an evolved psychology designed for small-scale groups.

  8. Muscle function and body composition profile in adolescents with restrictive anorexia nervosa: does resistance training help?

    Science.gov (United States)

    Fernández-del-Valle, Maria; Larumbe-Zabala, Eneko; Morande-Lavin, Gonzalo; Perez Ruiz, Margarita

    2016-01-01

    The aim of this study was to analyze the effects of short-term resistance training on the body composition profile and muscle function in a group of Anorexia Nervosa restricting type (AN-R) patients. The sample consisted of AN-R female adolescents (12.8 ± 0.6 years) allocated into the control and intervention groups (n = 18 each). Body composition and relative strength were assessed at baseline, after 8 weeks and 4 weeks following the intervention. Body mass index (BMI) increased throughout the study (p = 0.011). Significant skeletal muscle mass (SMM) gains were found in the intervention group (p = 0.045, d = 0.6) that correlated to the change in BMI (r = 0.51, p  0.60) with change in BMI in both the groups. Significant relative strength increases (p Anorexia Nervosa Restricting Type (AN-R) AN-R is a psychiatric disorder that has a major impact on muscle mass content and function. However, little or no attention has been paid to muscle recovery. High intensity resistance training is safe for AN-R after hospitalization and enhances the force generating capacity as well as muscle mass gains. Skeletal muscle mass content and muscular function improvements are partially maintained for a short period of time when the exercise program ceases.

  9. Heat treatment of a direct composite resin: influence on flexural strength

    Directory of Open Access Journals (Sweden)

    Caroline Lumi Miyazaki

    2009-09-01

    Full Text Available The purpose of this study was to evaluate the flexural strength of a direct composite, for indirect application, that received heat treatment, with or without investment. One indirect composite was used for comparison. For determination of the heat treatment temperature, thermogravimetric analysis (TGA and differential scanning calorimetry (DSC were performed, considering the initial weight loss temperature and glass transition temperature (Tg. Then, after photoactivation (600 mW/cm² - 40 s, the specimens (10 x 2 x 2 mm were heat-treated following these conditions: 170ºC for 5, 10 or 15 min, embedded or not embedded in investment. Flexural strength was assessed as a means to evaluate the influence of different heat treatment periods and investment embedding on mechanical properties. The data were analyzed by ANOVA and Tukey's test (α = 0.05. TGA showed an initial weight loss temperature of 180ºC and DSC showed a Tg value of 157°C. Heat treatment was conducted in an oven (Flli Manfredi, Italy, after 37°C storage for 48 h. Flexural strength was evaluated after 120 h at 37°C storage. The results showed that different periods and investment embedding presented similar statistical values. Nevertheless, the direct composite resin with treatments presented higher values (178.7 MPa compared to the indirect composite resin (146.0 MPa and the same direct composite submitted to photoactivation only (151.7 MPa. Within the limitations of this study, it could be concluded that the heat treatment increased the flexural strength of the direct composite studied, leading to higher mechanical strength compared to the indirect composite.

  10. Effect of Pre-heating on Microtensile Bond Strength of Composite Resin to Dentin.

    Directory of Open Access Journals (Sweden)

    Abdolrahim Davari

    2014-10-01

    Full Text Available Direct composite resin restorations are widely used and the impact of different storage temperatures on composites is not well understood. The purpose of this study was to evaluate the microtensile bond strength of composite to dentin after different pre-curing temperatures.Occlusal surfaces of 44 human molars were ground with diamond burs under water coolant and polished with 600 grit silicon carbide papers to obtain flat dentin surfaces. The dentin was etched with 37% phosphoric acid and bonded with Adper Single Bond 2 according to the manufacturer's instructions. The specimens were randomly divided into two groups (n=22 according to the composite resin applied: FiltekP60 and Filtek Z250. Each group included three subgroups of composite resin pre-curing temperatures (4°C, 23°C and 37°C. Composite resins were applied to the dentin surfaces in a plastic mold (8mm in diameter and 4mm in length incrementally and cured. Twenty-two composite-to-dentin hour-glass sticks with one mm(2 cross-sectional area per group were prepared. Microtensile bond strength measurements were made using a universal testing machine at a crosshead speed of one mm/min. For statistical analysis, t-test, one-way and two-way ANOVA were used. The level of significance was set at P<0.05.Filtek P60 pre-heated at 37ºC had significantly higher microtensile bond strength than Filtek Z250 under the same condition. The microtensile bond strengths were not significantly different at 4ºC, 23ºC and 37ºC subgroups of each composite resin group.Filtek P60 and Filtek Z250 did not have significantly different microtensile bond strengths at 4ºC and 23ºC but Filtek P60 had significantly higher microtensile bond strength at 37 ºC. Composite and temperature interactions had significant effects on the bond strength.

  11. Body composition of freshwater Wallago attu in relation to body size ...

    African Journals Online (AJOL)

    User

    2011-05-16

    May 16, 2011 ... water content. There was no significant influence of sex on body composition of W. attu. .... determined in duplicate for each fish using 1 g sub samples in a ... fish was calculated using a formula K = 100 x W/L3 by the method.

  12. Mineralization behavior and interface properties of BG-PVA/bone composite implants in simulated body fluid.

    Science.gov (United States)

    Ma, Yanxuan; Zheng, Yudong; Huang, Xiaoshan; Xi, Tingfei; Lin, Xiaodan; Han, Dongfei; Song, Wenhui

    2010-04-01

    Due to the non-bioactivity and poor conjunction performance of present cartilage prostheses, the main work here is to develop the bioactive glass-polyvinyl alcohol hydrogel articular cartilage/bone (BG-PVA/bone) composite implants. The essential criterion for a biomaterial to bond with living bone is well-matched mechanical properties as well as biocompatibility and bioactivity. In vitro studies on the formation of a surface layer of carbonate hydroxyl apatite (HCA) and the corresponding variation of the properties of biomaterials are imperative for their clinical application. In this paper, the mineralization behavior and variation of the interface properties of BG-PVA/bone composites were studied in vitro by using simulated body fluid (SBF). The mineralization and HCA layer formed on the interface between the BG-PVA hydrogel and bone in SBF could provide the composites with bioactivity and firmer combination. The compression property, shear strength and interface morphology of BG-PVA/bone composite implants varying with the immersion time in SBF were characterized. Also, the influence laws of the immersion time, content of BG in the composites and aperture of bones to the mineralization behavior and interface properties were investigated. The good mineralization behavior and enhanced conjunction performance of BG-PVA/bone composites demonstrated that this kind of composite implant might be more appropriate cartilage replacements.

  13. Mineralization behavior and interface properties of BG-PVA/bone composite implants in simulated body fluid

    Energy Technology Data Exchange (ETDEWEB)

    Ma Yanxuan; Zheng Yudong; Huang Xiaoshan; Xi Tingfei; Han Dongfei [School of Materials Science and Engineering, Beijing University of Science and Technology, Beijing 100083 (China); Lin Xiaodan [College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Song Wenhui, E-mail: zhengyudong@mater.ustb.edu.c, E-mail: wenhui.song@brunel.ac.u [Wolfson Center for Materials Processing, School of Engineering and Design, Brunel University, West London, UB8 3PH (United Kingdom)

    2010-04-15

    Due to the non-bioactivity and poor conjunction performance of present cartilage prostheses, the main work here is to develop the bioactive glass-polyvinyl alcohol hydrogel articular cartilage/bone (BG-PVA/bone) composite implants. The essential criterion for a biomaterial to bond with living bone is well-matched mechanical properties as well as biocompatibility and bioactivity. In vitro studies on the formation of a surface layer of carbonate hydroxyl apatite (HCA) and the corresponding variation of the properties of biomaterials are imperative for their clinical application. In this paper, the mineralization behavior and variation of the interface properties of BG-PVA/bone composites were studied in vitro by using simulated body fluid (SBF). The mineralization and HCA layer formed on the interface between the BG-PVA hydrogel and bone in SBF could provide the composites with bioactivity and firmer combination. The compression property, shear strength and interface morphology of BG-PVA/bone composite implants varying with the immersion time in SBF were characterized. Also, the influence laws of the immersion time, content of BG in the composites and aperture of bones to the mineralization behavior and interface properties were investigated. The good mineralization behavior and enhanced conjunction performance of BG-PVA/bone composites demonstrated that this kind of composite implant might be more appropriate cartilage replacements.

  14. Composition and function of P bodies in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Luis David Maldonado-Bonilla

    2014-05-01

    Full Text Available mRNA accumulation is tightly regulated by diverse molecular pathways. The identification and characterization of enzymes and regulatory proteins involved in controlling the fate of mRNA offers the possibility to broaden our understanding of posttranscriptional gene regulation. Processing bodies (P bodies, PB are cytoplasmic protein complexes involved in degradation and translational arrest of mRNA. Composition and dynamics of these subcellular structures have been studied in animal systems, yeasts and in the model plant Arabidopsis. Their assembly implies the aggregation of specific factors related to decapping, deadenylation and exoribonucleases that operate synchronously to regulate certain mRNA targets during development and adaptation to stress. Although the general function of PB along with the flow of genetic information is understood, several questions still remain open. This review summarizes data on the composition, potential molecular roles, and biological significance of PB and potentially related proteins in Arabidopsis.

  15. Body composition changes in essential hypertension before and after treatment

    International Nuclear Information System (INIS)

    Fueloep, T. Jr.; Worum, I.; Csongor, J.; Ujhelyi, L.; Foeris, G.

    1986-01-01

    The body composition of 30 elderly (22 females: 78,2+7,6; 8 males: 80,4+5,4 yrs) and 38 middle-aged (27 females: 45,5+10.3; 11 males: 42,3+8,7 yrs) people suffering of essential hypertension determined by complex clinical and biological examinations (BP: 160-180/100-200 Hgmm), was determined before and after treatment. Most of them (78%) could be reassessed after 3 month of treatment (beta-blocking drugs or diuretics). The authors also investigated a few numbers (n=10) of patients presenting a hypertensive crisis treated with vasodilatant drugs and diuretics during 1 week of period. The hormonal status of all of them was assessed at the same time. The body composition was determined by multiple-isotope method

  16. Nutrition, endocrinology, and body composition during space flight

    Science.gov (United States)

    Lane, H. W.; Gretebeck, R. J.; Smith, S. M.

    1998-01-01

    Space flight induces endocrine changes that perturb metabolism. This altered metabolism affects both the astronauts' body composition and the nutritional requirements necessary to maintain their health. During the last 25 years, a combination of studies conducted on Skylab (the first U.S. space laboratory), U.S. Shuttle flights, and Soviet and Russian flights provides a range of data from which general conclusions about energy and protein requirements can be drawn. We have reviewed the endocrine data from those studies and related it to changes in body composition. From these data it appears that protein and energy intake of astronauts are similar to those on Earth. However, a combination of measures, including exercise, appropriate diet, and, potentially, drugs, is required to provide the muscle health needed for long duration space flight.

  17. Oxidation Kinetics and Strength Degradation of Carbon Fibers in a Cracked Ceramic Matrix Composite

    Science.gov (United States)

    Halbig, Michael C.

    2003-01-01

    Experimental results and oxidation modeling will be presented to discuss carbon fiber susceptibility to oxidation, the oxidation kinetics regimes and composite strength degradation and failure due to oxidation. Thermogravimetric Analysis (TGA) was used to study the oxidation rates of carbon fiber and of a pyro-carbon interphase. The analysis was used to separately obtain activation energies for the carbon constituents within a C/SiC composite. TGA was also conducted on C/SiC composite material to study carbon oxidation and crack closure as a function of temperature. In order to more closely match applications conditions C/SiC tensile coupons were also tested under stressed oxidation conditions. The stressed oxidation tests show that C/SiC is much more susceptible to oxidation when the material is under an applied load where the cracks are open and allow for oxygen ingress. The results help correlate carbon oxidation with composite strength reduction and failure.

  18. Growth hormone deficiency in the transition period: body composition and gonad function.

    Science.gov (United States)

    Balercia, G; Giovannini, L; Paggi, F; Spaziani, M; Tahani, N; Boscaro, M; Lenzi, A; Radicioni, A

    2011-10-01

    Recombinant GH therapy is normally administered to GH-deficient children in order to achieve a satisfactory height - the main target during childhood and adolescence. However, the role of GH does not end once final height has been reached, but continues during the so-called transition period. In this phase of life, the body undergoes several changes, both physical and psychological, that culminate in adulthood. During this period, GH has a part in numerous metabolic functions. These include the lipid profile, where it increases HDL and reduces LDL, with the global effect of cardiovascular protection. It also has important effects on body composition (improved muscle strength and lean body mass and reduced body fat), the achievement of proper peak bone density, and gonad maturation. Retesting during the transition period, involving measurement of IGF-I plus a provocative test (insulin tolerance test or GHRH + arginine test), is thus necessary to establish any persistent GH deficiency requiring additional replacement therapy. The close cooperation of the medical professionals involved in the patient's transition from a pediatric to an adult endocrinologist is essential. The aim of this review is to point out the main aspects of GH treatment on body composition, metabolic and gonad functions in the transition period.

  19. Detecting meaningful body composition changes in athletes using dual-energy x-ray absorptiometry

    International Nuclear Information System (INIS)

    Colyer, Steffi L; Roberts, Simon P; Thompson, Dylan; Stokes, Keith A; Bilzon, James L J; Salo, Aki I T; Robinson, Jonathan B

    2016-01-01

    Dual-energy x-ray absorptiometry (DXA) imaging is considered to provide a valid and reliable estimation of body composition when stringent scanning protocols are adopted. However, applied practitioners are not always able to achieve this level of control and the subsequent impact on measurement precision is not always taken into account when evaluating longitudinal body composition changes. The primary aim of this study was to establish the reliability of DXA in an applied elite sport setting to investigate whether real body composition changes can be detected. Additionally, the performance implications of these changes during the training year were investigated. Forty-eight well-trained athletes (from four diverse sports) underwent two DXA scans using a ‘real-world’ approach (with limited pre-scan controls), typically within 48 h, to quantify typical error of measurement (TEM). Twenty-five athletes underwent further scans, before and after specific training and competition blocks. ‘True’ body composition changes were evaluated using 2  ×  TEM thresholds. Twelve bob skeleton athletes also performed countermovement jump and leg press tests at each time point. Many ‘true’ body composition changes were detected and coincided with the primary training emphases (e.g. lean mass gains during hypertrophy-based training). Clear relationships (r  ±  90% CI) were observed between performance changes (countermovement jump and leg press) and changes in lean mass (0.53  ±  0.26 and 0.35  ±  0.28, respectively) and fat mass (−0.44  ±  0.27 and  −0.37  ±  0.28, respectively). DXA was able to detect real body composition changes without the use of stringent scanning controls. Associations between changes in body composition and performance demonstrated the potential influence of these changes on strength and power indices. (paper)

  20. International society of sports nutrition position stand: diets and body composition.

    Science.gov (United States)

    Aragon, Alan A; Schoenfeld, Brad J; Wildman, Robert; Kleiner, Susan; VanDusseldorp, Trisha; Taylor, Lem; Earnest, Conrad P; Arciero, Paul J; Wilborn, Colin; Kalman, Douglas S; Stout, Jeffrey R; Willoughby, Darryn S; Campbell, Bill; Arent, Shawn M; Bannock, Laurent; Smith-Ryan, Abbie E; Antonio, Jose

    2017-01-01

    Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature regarding the effects of diet types (macronutrient composition; eating styles) and their influence on body composition. The ISSN has concluded the following. 1) There is a multitude of diet types and eating styles, whereby numerous subtypes fall under each major dietary archetype. 2) All body composition assessment methods have strengths and limitations. 3) Diets primarily focused on fat loss are driven by a sustained caloric deficit. The higher the baseline body fat level, the more aggressively the caloric deficit may be imposed. Slower rates of weight loss can better preserve lean mass (LM) in leaner subjects. 4) Diets focused primarily on accruing LM are driven by a sustained caloric surplus to facilitate anabolic processes and support increasing resistance-training demands. The composition and magnitude of the surplus, as well as training status of the subjects can influence the nature of the gains. 5) A wide range of dietary approaches (low-fat to low-carbohydrate/ketogenic, and all points between) can be similarly effective for improving body composition. 6) Increasing dietary protein to levels significantly beyond current recommendations for athletic populations may result in improved body composition. Higher protein intakes (2.3-3.1 g/kg FFM) may be required to maximize muscle retention in lean, resistance-trained subjects under hypocaloric conditions. Emerging research on very high protein intakes (>3 g/kg) has demonstrated that the known thermic, satiating, and LM-preserving effects of dietary protein might be amplified in resistance-training subjects. 7) The collective body of intermittent caloric restriction research demonstrates no significant advantage over daily caloric restriction for improving body composition. 8) The long-term success of a diet depends upon compliance and suppression or

  1. General many-body formalism for composite quantum particles.

    Science.gov (United States)

    Combescot, M; Betbeder-Matibet, O

    2010-05-21

    This Letter provides a formalism capable of exactly treating Pauli blocking between n-fermion particles. This formalism is based on an operator algebra made of commutators and anticommutators which contrasts with the usual scalar formalism of Green functions developed half a century ago for elementary quantum particles. We also provide the diagrams which visualize the very specific many-body physics induced by fermion exchanges between composite quantum particles.

  2. High strength-high conductivity Cu-Fe composites produced by powder compaction/mechanical reduction

    Science.gov (United States)

    Verhoeven, J.D.; Spitzig, W.A.; Gibson, E.D.; Anderson, I.E.

    1991-08-27

    A particulate mixture of Cu and Fe is compacted and mechanically reduced to form an ''in-situ'' Cu-Fe composite having high strength and high conductivity. Compaction and mechanical reduction of the particulate mixture are carried out at a temperature and time at temperature selected to avoid dissolution of Fe into the Cu matrix particulates to a harmful extent that substantially degrades the conductivity of the Cu-Fe composite. 5 figures.

  3. High strength-high conductivity Cu--Fe composites produced by powder compaction/mechanical reduction

    Science.gov (United States)

    Verhoeven, John D.; Spitzig, William A.; Gibson, Edwin D.; Anderson, Iver E.

    1991-08-27

    A particulate mixture of Cu and Fe is compacted and mechanically reduced to form an "in-situ" Cu-Fe composite having high strength and high conductivity. Compaction and mechanical reduction of the particulate mixture are carried out at a temperature and time at temperature selected to avoid dissolution of Fe into the Cu matrix particulates to a harmful extent that substantially degrades the conductivity of the Cu-Fe composite.

  4. Optimisation of hybrid high-modulus/high-strength carbon fiber reinforced plastic composite drive

    OpenAIRE

    Montagnier, Olivier; Hochard, Christian

    2011-01-01

    International audience; This study deals with the optimisation of hybrid composite drive shafts operating at subcritical or supercritical speeds, using a genetic algorithm. A formulation for the flexural vibrations of a composite drive shaft mounted on viscoelastic supports including shear effects is developed. In particular, an analytic stability criterion is developed to ensure the integrity of the system in the supercritical regime. Then it is shown that the torsional strength can be compu...

  5. Menstrual Changes in Body Composition of Female Athletes.

    Science.gov (United States)

    Stachoń, Aleksandra Jadwiga

    2016-06-01

    The aim of the study was to determine whether the tendencies and scope of changes in body mass, body composition and body girths across the menstrual cycle were similar or different in women of different body build. Anthropometric examinations were carried out in a group of 40 naturally regularly menstruated females practicing team sports (aged 19-21, B-v 169.3+/-6.4 cm, body mass 59.6+/-7.0 kg), in the follicular, periovulatory and luteal phases of the menstrual cycle. The phases were determined on the basis of data from two consecutive menstrual cycles taking into account the cycle’s length. To establish the type of body build, Body Mass Index, hydration status and skinfold thickness were measured. For a statistical analysis, a multiple comparisons with multiple confidence intervals were applied. The increase in body mass between the follicular and the luteal phases was observed in all groups of women, the biggest gain was recorded in slim women, who in the luteal phase weighted 0.8 kg more. The amount of fat mass increased significantly across the menstrual cycle only in more hydrated (by about 0.66 kg) and slim women (by about 0.54 kg). Significant changes between consecutive phases of the menstrual cycle in waist and hip girths, and suprailiac skinfold thickness in some groups of women also indicate influence of fatness and hydration status and slenderness. In view of the presented results, the body build seems important for an analysis of the pattern of each component’s changes across the menstrual cycle, especially for female athletes. Certain changes can be seen only in some groups of women, therefore somatic features can be considered as a predictor of the intensity of changes.

  6. Association between Body Composition and Motor Performance in Preschool Children

    Directory of Open Access Journals (Sweden)

    Tanja H. Kakebeeke

    2017-09-01

    Full Text Available Objective: Being overweight makes physical movement more difficult. Our aim was to investigate the association between body composition and motor performance in preschool children. Methods: A total of 476 predominantly normal-weight preschool children (age 3.9 ± 0.7 years; m/f: 251/225; BMI 16.0 ± 1.4 kg/m2 participated in the Swiss Preschoolers' Health Study (SPLASHY. Body composition assessments included skinfold thickness, waist circumference (WC, and BMI. The Zurich Neuromotor Assessment (ZNA was used to assess gross and fine motor tasks. Results: After adjustment for age, sex, socioeconomic status, sociocultural characteristics, and physical activity (assessed with accelerometers, skinfold thickness and WC were both inversely correlated with jumping sideward (gross motor task β-coefficient -1.92, p = 0.027; and -3.34, p = 0.014, respectively, while BMI was positively correlated with running performance (gross motor task β-coefficient 9.12, p = 0.001. No significant associations were found between body composition measures and fine motor tasks. Conclusion: The inverse associations between skinfold thickness or WC and jumping sideward indicates that children with high fat mass may be less proficient in certain gross motor tasks. The positive association between BMI and running suggests that BMI might be an indicator of fat-free (i.e., muscle mass in predominately normal-weight preschool children.

  7. Anorexia nervosa and nutritional assessment: contribution of body composition measurements.

    Science.gov (United States)

    Mattar, Lama; Godart, Nathalie; Melchior, Jean Claude; Pichard, Claude

    2011-06-01

    The psychiatric condition of patients suffering from anorexia nervosa (AN) is affected by their nutritional status. An optimal assessment of the nutritional status of patients is fundamental in understanding the relationship between malnutrition and the psychological symptoms. The present review evaluates some of the available methods for measuring body composition in patients with AN. We searched literature in Medline using several key terms relevant to the present review in order to identify papers. Only articles in English or French were reviewed. A brief description is provided for each body composition technique, with its applicability in AN as well as its limitation. All methods of measuring body composition are not yet validated and/or feasible in patients with AN. The present review article proposes a practical approach for selecting the most appropriate methods depending on the setting, (i.e. clinical v. research) and the goal of the assessment (initial v. follow-up) in order to have a more personalised treatment for patients suffering from AN.

  8. Effect of Fiber Volume Fraction and Water Absorption toward Bending Strength of Coconut Filters/ Polyester Composite

    Directory of Open Access Journals (Sweden)

    I Putu Lokantara

    2012-11-01

    Full Text Available The variation of fibre volume and the duration of water soaking take influence on the mechanical properties of composite. This research aim is to know the influence of fraction volume fibre and soaking duration on the mineral watertoward the tensile strength and flexural of polyester-coconut-tapis composite. This research used coconut-tapis fibre which is cut 1 cm in length with 0%, 5%, 7,5%, and 10% fiber volume fraction, unsaturated-polyester (UPRs matrix resin type Yucalac 157 BQTN-EX, and MEKPO hardener. The flexure specimen are made by press hand lay-up method and cut according ASTM D790-03 for the flexure test. The result of flexure test shows that the duration of soaking and the fiber volume fraction give a significant effect on the flexural strength of composite. The highest strength are reached by composite with 10% fibre volume on 48 hour soaking time equal to 41.994 MPa. The flexure modulus happenend shows increasing until 24 hour soaking time. The highest modulus are reached by composite with 10% fibre volume equal to 7.114 GPa while the lowest are reached by composite with 0% fibre volume equal to 3,023 GPa.

  9. Microshear bond strength of composite resins to enamel and porcelain substrates utilizing unfilled versus filled resins.

    Science.gov (United States)

    Najafi-Abrandabadi, Ahmad; Najafi-Abrandabadi, Siamak; Ghasemi, Amir; Kotick, Philip G

    2014-11-01

    Failures such as marginal discoloration and composite chipping are still the problems of tooth-colored restorations on the substrate of enamel and porcelain, which some of these problems are consequently as a result of failures in the bonding layer. Using filled resin has been recently introduced to increase the bond strength of this layer. The aim of this study was to compare the microshear bond strength (μ-SBS) of composite resins to enamel incubated in periods of 24 h and 9 months and porcelain with unfilled resin and flowable composites (filled resin). In this in vitro study, two groups of 75 enamel samples with different storage times (24 h and 9 months) and a group of 75 porcelain samples were used. They were divided into 5 experimental groups of 15 samples in each. Composite cylinders in tygon tubes were bonded on the surface of acid-etched enamel and pretreated porcelain. Wave, Wave MV, Wave HV, Grandioflow and Margin Bond were used as bonding agents. The μ-SBS was measured at the speed of 1.0 mm/min. The bond strengths were analyzed with one-way analysis of variance (ANOVA) test followed by Tukey test. P composites (filled resins) can be used instead of unfilled resins in bonding composite resins to enamel and porcelain substrates.

  10. Fracture Surface Morphology and Impact Strength of Cellulose/PLA Composites.

    Science.gov (United States)

    Gao, Honghong; Qiang, Tao

    2017-06-07

    Polylactide (PLA)-based composite materials reinforced with ball-milled celluloses were manufactured by extrusion blending followed by injection molding. Their surface morphology from impact fracture were imaged with scanning electron microscopy (SEM) and investigated by calculating their fractal dimensions. Then, linear regression was used to explore the relationship between fractal dimension and impact strength of the resultant cellulose/PLA composite materials. The results show that filling the ball-milled celluloses into PLA can improve the impact toughness of PLA by a minimum of 38%. It was demonstrated that the fracture pattern of the cellulose/PLA composite materials is different from that of pristine PLA. For the resultant composite materials, the fractal dimension of the impact fractured surfaces increased with increasing filling content and decreasing particle size of the ball-milled cellulose particles. There were highly positive correlations between fractal dimension of the fractured surfaces and impact strength of the cellulose/PLA composites. However, the linearity between fractal dimension and impact strength were different for the different methods, due to their different R-squared values. The approach presented in this work will help to understand the structure-property relationships of composite materials from a new perspective.

  11. Dentin-composite bond strength measurement using the Brazilian disk test.

    Science.gov (United States)

    Carrera, Carola A; Chen, Yung-Chung; Li, Yuping; Rudney, Joel; Aparicio, Conrado; Fok, Alex

    2016-09-01

    This study presents a variant of the Brazilian disk test (BDT) for assessing the bond strength between composite resins and dentin. Dentin-composite disks (ϕ 5mm×2mm) were prepared using either Z100 or Z250 (3M ESPE) in combination with one of three adhesives, Adper Easy Bond (EB), Adper Scotchbond Multi-Purpose (MP) and Adper Single Bond (SB), and tested under diametral compression. Acoustic emission (AE) and digital image correlation (DIC) were used to monitor debonding of the composite from the dentin ring. A finite element (FE) model was created to calculate the bond strengths using the failure loads. Fracture modes were examined by scanning electron microscopy (SEM). Most specimens fractured along the dentin-resin composite interface. DIC and AE confirmed interfacial debonding immediately before fracture of the dentin ring. Results showed that the mean bond strength with EB (14.9±1.9MPa) was significantly higher than with MP (13.2±2.4MPa) or SB (12.9±3.0MPa) (p0.05). Z100 (14.5±2.3MPa) showed higher bond strength than Z250 (12.7±2.5MPa) (pstrength between dentin and composite, with zero premature failure, reduced variability in the measurements, and consistent failure at the dentin-composite interface. The new test could help to predict the clinical performance of adhesive systems more effectively and consistently by reducing the coefficient of variation in the measured bond strength. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Compressive strength of dental composites photo-activated with different light tips

    International Nuclear Information System (INIS)

    Galvão, M R; Campos, E A; Rastelli, A N S; Andrade, M F; Caldas, S G F R; Calabrez-Filho, S; Bagnato, V S

    2013-01-01

    The aim of this study was to evaluate the compressive strength of microhybrid (Filtek™ Z250) and nanofilled (Filtek™ Supreme XT) composite resins photo-activated with two different light guide tips, fiber optic and polymer, coupled with one LED. The power density was 653 mW cm −2 when using the fiber optic light tip and 596 mW cm −2 with the polymer. After storage in distilled water at 37 ± 2 °C for seven days, the samples were subjected to mechanical testing of compressive strength in an EMIC universal mechanical testing machine with a load cell of 5 kN and speed of 0.5 mm min −1 . The statistical analysis was performed using ANOVA with a confidence interval of 95% and Tamhane’s test. The results showed that the mean values of compressive strength were not influenced by the different light tips (p > 0.05). However, a statistical difference was observed (p < 0.001) between the microhybrid composite resin photo-activated with the fiber optic light tip and the nanofilled composite resin. Based on these results, it can be concluded that microhybrid composite resin photo-activated with the fiber optic light tip showed better results than nanofilled, regardless of the tip used, and the type of the light tip did not influence the compressive strength of either composite. Thus, the presented results suggest that both the fiber optic and polymer light guide tips provide adequate compressive strength to be used to make restorations. However, the fiber optic light tip associated with microhybrid composite resin may be an interesting option for restorations mainly in posterior teeth. (paper)

  13. Body composition and cardiac dimensions in elite rhythmic gymnasts.

    Science.gov (United States)

    Galetta, F; Franzoni, F; D'alessandro, C; Piazza, M; Tocchini, L; Fallahi, P; Antonelli, A; Cupisti, F; Santoro, G

    2015-09-01

    Rhythmic gymnasts are often believed to be a population at risk of malnutrition because of their tendency to keep a low weight and a lean appearance for better athletic performance, and because they start intensive training at a very young age. The purpose of this study was to evaluate in adolescent elite gymnasts the effects of physical activity on body composition and cardiac morphology and function. Sixteen national level rhythmic gymnasts and 16 control adolescent female underwent anthropometric measurements, bioelectric impedance and echocardiography to assess body composition and cardiac morphology and function. As compared to controls, gymnasts had lower body mass index (16.9±1.1 vs. 18.7±1.0, Panalysis showed a lower percentage of body fat in the gymnasts, together with a higher percentage of fat-free mass. Echocardiographic findings indicate that elite rhythmic gymnastics present left ventricular remodeling as training-induced cardiac adaptation. Intensive training, dietary attitude and evident leanness of rhythmic gymnasts are not associated with cardiac abnormalities, as it is the case of pathological leanness.

  14. Heterogeneous composite bodies with isolated lenticular shaped cermet regions

    Science.gov (United States)

    Sherman, Andrew J [Cirtland Hills, OH

    2009-12-22

    A heterogeneous body having ceramic rich cermet regions in a more ductile metal matrix. The heterogeneous bodies are formed by thermal spray operations on metal substrates. The thermal spray operations apply heat to a cermet powder and project it onto a solid substrate. The cermet powder is composed of complex composite particles in which a complex ceramic-metallic core particle is coated with a matrix precursor. The cermet regions are generally comprised of complex ceramic-metallic composites that correspond approximately to the core particles. The cermet regions are approximately lenticular shaped with an average width that is at least approximately twice the average thickness. The cermet regions are imbedded within the matrix phase and generally isolated from one another. They have obverse and reverse surfaces. The matrix phase is formed from the matrix precursor coating on the core particles. The amount of heat applied during the formation of the heterogeneous body is controlled so that the core particles soften but do not become so fluid that they disperse throughout the matrix phase. The force of the impact on the surface of the substrate tends to flatten them. The flattened cermet regions tend to be approximately aligned with one another in the body.

  15. The interfacial strength of carbon nanofiber epoxy composite using single fiber pullout experiments.

    Science.gov (United States)

    Manoharan, M P; Sharma, A; Desai, A V; Haque, M A; Bakis, C E; Wang, K W

    2009-07-22

    Carbon nanotubes and nanofibers are extensively researched as reinforcing agents in nanocomposites for their multifunctionality, light weight and high strength. However, it is the interface between the nanofiber and the matrix that dictates the overall properties of the nanocomposite. The current trend is to measure elastic properties of the bulk nanocomposite and then compare them with theoretical models to extract the information on the interfacial strength. The ideal experiment is single fiber pullout from the matrix because it directly measures the interfacial strength. However, the technique is difficult to apply to nanocomposites because of the small size of the fibers and the requirement for high resolution force and displacement sensing. We present an experimental technique for measuring the interfacial strength of nanofiber-reinforced composites using the single fiber pullout technique and demonstrate the technique for a carbon nanofiber-reinforced epoxy composite. The experiment is performed in situ in a scanning electron microscope and the interfacial strength for the epoxy composite was measured to be 170 MPa.

  16. BODY COMPOSITION IN HEMODIALYSIS AND PERITONEAL DIALYSIS PATIENTS

    Directory of Open Access Journals (Sweden)

    Nam Ho Kim

    2012-06-01

    Full Text Available Bioimpedance analysis is a reliable technique for determining post dialysis target weight. Using this technique, we can understand body fluid status easier and conveniently. Moreover this technique can be used for check nutrition status and nutritional status of dialysis patients. We compared the body fluid status and nutrition status between hemodialysis (HD patients and peritoneal dialysis (PD patients by BCM (Body composition monitor technique. We studied 48 (30 males and 18 females PD patients, 21 (10 males and 11 females HD patients. Body composition monitoring (BCM, Fesenitus Medical Care, Germany was used as a tool for the analysis of bioimpedance. Extracellular water, Total body water, Intracellular water, Overhydration, E/I, Lean tissue mass, Fat Tissue mass was measured and those results were compared between two groups. HD patients were more hydrated than PD patients (61.9% vs. 35.4% and nutritional status such as LTI was poorer than peritoneal dialysis patients (11.7±1.7 vs. 15.3±2.6. Although total body water is more abundant in peritoneal patients (29.4±5.5L vs. 35.9±6.2L, Extracellular water and intracellular water ratio was relatively higher in Hemodialysis patients (E/I 0.98±0.13 vs. 0.87±0.12. The nutrition status was better in PD patients by comparing the percent of lean tissue mass (LTM% between two groups (LTM% 52.1±10.6% vs. 66.8±11.3. In conclusions, Hemodialysis patients were more hydrated with poorer nutrition status than peritoneal dialysis patients, but, due to the significant difference of age between two groups, further study should be required.

  17. Determination of Some Physical Fitness and Body Composition Characteristics of Young Bocce Players in Turkish National Team

    Directory of Open Access Journals (Sweden)

    Mutlu Türkmen

    2018-02-01

    Full Text Available Bocce is gaining popularity throughout the world and is a game that is dominated by aerobic and anaerobic power-capacity, endurance, and strength and body composition. These are all important factors in order to reach a successful performance in Bocce. The purpose of this study was to determine some physical fi tness and body composition characteristics of young Bocce players in Turkish national team. A total of 26 six (14 female age 21.00±8.47 and 12 male age 19.58±3.34 Bocce players from National Team of Turkey participated in this study voluntarily. Subjects’ height, body weight, body mass index and body fat percentage were measured. Body fat percentage was determined by Yuhasz formula, and isometric dynamometer was used in order to determine knee, back, grip strength. The sit and reach test was used for the determination of fl exibility. Results indicated that Bocce players have normal body mass index and body fat percentage and ectomorphy-mesomorphy properties. Results of the isometric knee, back, right-left grip strength values of Bocce players was 77.54±24.8 kg, 90.54±26.85 kg and 36.10±9.91-34.27±10.08 respectively and have normal fl exibility (32.5±5.86. As a conclusion, the fi ndings of the present study indicated that Bocce players have almost average body fat percentage, isometric strength and fl exibility function.

  18. From physical strength to corporal aesthetics: social relantionship transformation impresssed in the body

    Directory of Open Access Journals (Sweden)

    Vilson Aparecido da Mata

    2008-06-01

    Full Text Available Based on Locke and Rousseau, the aim of the present article is to describe the forms of body understanding in that transitional historical period. Taking into account the unemployment increase in a period of a steady technological development, the human body is seen as occupying a different place from that by which it was characterised in the rising bourgeois society. Both in Locke and Rousseau, body building has an important place in the individual education, since material goods necessary to life produced through physical effort in that time. That is why physical exercise is so important for these authors. Work process transformations, from the beginning of the bourgeois society up to now, show a tendency to replace physical strength by mechanical power and emphasize individual qualities such as body building and aesthetics. This tendency is not limited to the sphere of individual interests, but shows the social demands formed in man’s daily struggles for life. Nowadays, when physical effort becomes more and more unessential and a standardised corporal aesthetics is required by the market it is necessary to rethink the role of education and specially physical education in the individual development and recuperate the historical contents to better understand the forms of struggle for life. Each historical period impresses man’s ideals in his body.

  19. EFFECT OF SEA WATER ON THE STRENGTH OF POROUS CONCRETE CONTAINING PORTLAND COMPOSITE CEMENT AND MICROFILAMENT POLYPROPYLENE FIBER

    OpenAIRE

    TJARONGE, M.W

    2011-01-01

    The aim of this research is to study the influence of sea water on the strength of porous concrete containing Portland Composite cement and micro monofilament polypropylene fibre. The specimens of porous concrete were immersed in the sea water up to 28 days. The compressive strength test and flexural strength test were carried out at 3, 7 and 28 days in order to investigate the strength development. The test result indicated that the strength of porous concrete can develop in t...

  20. Microstructure Effects on Spall Strength of Titanium-based Bulk Metallic Glass Composites

    Science.gov (United States)

    Diaz, Rene; Hofmann, Douglas; Thadhani, Naresh; Georgia Tech Team; GT-JPL Collaboration

    2017-06-01

    The spall strength of Ti-based metallic glass composites is investigated as a function of varying volume fractions (0-80%) of in-situ formed crystalline dendrites. With increasing dendrite content, the topology changes such that neither the harder glass nor the softer dendrites dominate the microstructure. Plate-impact experiments were performed using the 80-mm single-stage gas gun over impact stresses up to 18 GPa. VISAR interferometry was used to obtain rear free-surface velocity profiles revealing the velocity pullback spall failure signals. The spall strengths were higher than for Ti-6Al-4V alloy, and remained high up to impact stress. The influence of microstructure on the spall strength is indicated by the constants of the power law fit with the decompression strain rate. Differences in fracture behavior reveal void nucleation as a dominant mechanism affecting the spall strength. The microstructure with neither 100% glass nor with very high crystalline content, provides the most tortuous path for fracture and therefore highest spall strength. The results allow projection of spall strength predictions for design of in-situ formed metallic glass composites. ARO Grant # W911NF-09 ``1-0403 NASA JPL Contract # 1492033 ``Prime # NNN12AA01C; NSF GRFP Grant #DGE-1148903; and NDSE & G.

  1. Rotational Failure of Rubble-pile Bodies: Influences of Shear and Cohesive Strengths

    Science.gov (United States)

    Zhang, Yun; Richardson, Derek C.; Barnouin, Olivier S.; Michel, Patrick; Schwartz, Stephen R.; Ballouz, Ronald-Louis

    2018-04-01

    The shear and cohesive strengths of a rubble-pile asteroid could influence the critical spin at which the body fails and its subsequent evolution. We present results using a soft-sphere discrete element method to explore the mechanical properties and dynamical behaviors of self-gravitating rubble piles experiencing increasing rotational centrifugal forces. A comprehensive contact model incorporating translational and rotational friction and van der Waals cohesive interactions is developed to simulate rubble-pile asteroids. It is observed that the critical spin depends strongly on both the frictional and cohesive forces between particles in contact; however, the failure behaviors only show dependence on the cohesive force. As cohesion increases, the deformation of the simulated body prior to disruption is diminished, the disruption process is more abrupt, and the component size of the fissioned material is increased. When the cohesive strength is high enough, the body can disaggregate into similar-size fragments, which could be a plausible mechanism to form asteroid pairs or active asteroids. The size distribution and velocity dispersion of the fragments in high-cohesion simulations show similarities to the disintegrating asteroid P/2013 R3, indicating that this asteroid may possess comparable cohesion in its structure and experience rotational fission in a similar manner. Additionally, we propose a method for estimating a rubble pile’s friction angle and bulk cohesion from spin-up numerical experiments, which provides the opportunity for making quantitative comparisons with continuum theory. The results show that the present technique has great potential for predicting the behaviors and estimating the material strengths of cohesive rubble-pile asteroids.

  2. Creep-rupture strength prediction of an epoxy composite under tension

    Czech Academy of Sciences Publication Activity Database

    Krastev, R.K.; Zachariev, G.; Hristova, J.; Minster, Jiří

    2009-01-01

    Roč. 13, č. 2 (2009), s. 207-214 ISSN 1385-2000 Institutional research plan: CEZ:AV0Z20710524 Keywords : materials testing * creep * strength prediction Subject RIV: JI - Composite Materials Impact factor: 1.051, year: 2009

  3. Effect of different dispersants in compressive strength of carbon fiber cementitious composites

    Science.gov (United States)

    Lestari, Yulinda; Bahri, Saiful; Sugiarti, Eni; Ramadhan, Gilang; Akbar, Ari Yustisia; Martides, Erie; Khaerudini, Deni S.

    2013-09-01

    Carbon Fiber Cementitious Composites (CFCC) is one of the most important materials in smart concrete applications. CFCC should be able to have the piezoresistivity properties where its resistivity changes when there is applied a stress/strain. It must also have the compressive strength qualification. One of the important additives in carbon fiber cementitious composites is dispersant. Dispersion of carbon fiber is one of the key problems in fabricating piezoresistive carbon fiber cementitious composites. In this research, the uses of dispersants are methylcellulose, mixture of defoamer and methylcellulose and superplasticizer based polycarboxylate. The preparation of composite samples is similar as in the mortar technique according to the ASTM C 109/109M standard. The additives material are PAN type carbon fibers, methylcellulose, defoamer and superplasticizer (as water reducer and dispersant). The experimental testing conducts the compressive strength and resistivity at various curing time, i.e. 3, 7 and 28 days. The results obtained that the highest compressive strength value in is for the mortar using superplasticizer based polycarboxylate dispersant. This also shown that the distribution of carbon fiber with superplasticizer is more effective, since not reacting with the cementitious material which was different from the methylcellulose that creates the cement hydration reaction. The research also found that the CFCC require the proper water cement ratio otherwise the compressive strength becomes lower.

  4. Effect of Ultrasonic Versus Manual Cementation on the Fracture Strength of Resin Composite Laminates

    NARCIS (Netherlands)

    Ozcan, M.; Mese, A.

    2009-01-01

    This study evaluated the effect of conventional versus ultrasonic cementation techniques on the fracture strength of resin composite laminates. In addition, the failure modes were assessed. Window-type preparations I mm above the cemento-enamel junction were made on intact human maxillary central

  5. Characterization of compressive and short beam shear strength of bamboo opened cell foam core sandwich composites

    Energy Technology Data Exchange (ETDEWEB)

    Setyawan, Paryanto Dwi, E-mail: paryanto-ds@yahoo.com; Sugiman,; Saputra, Yudhi [Department of Mechanical Engineering, Faculty of Engineering, University of Mataram, Mataram, West Nusa Tenggara (Indonesia)

    2016-03-29

    The paper presents the compressive and the short beam shear strength of a sandwich composite with opened cell foam made of bamboo fiber as the core and plywood as the skins. The core thickness was varied from 10 mm to 40 mm keeping the volume fraction of fiber constant. Several test s were carried out including the core density, flatwise compressive and the short beam shear testing in three point bending. The results show that the density of bamboo opened cell foam is comparable with commercial plastic foam, such as polyurethane foam. The compressive strength tends to increase linearly with increasing the core thickness. The short beam shear failure load of the sandwich composite increases with the increase of core thickness, however on the contrary, the short beam shear strength which tends to sharply decrease from the thickness of 10 mm to 30 mm and then becomes flat.

  6. An investigation of the compressive strength of Kevlar 49/epoxy composites

    Science.gov (United States)

    Kulkarni, S. V.; Rosen, B. W.; Rice, J. S.

    1975-01-01

    Tests were performed to evaluate the effect of a wide range of variables including matrix properties, interface properties, fiber prestressing, secondary reinforcement, and others on the ultimate compressive strength of Kevlar 49/epoxy composites. Scanning electron microscopy is used to assess the resulting failure surfaces. In addition, a theoretical study is conducted to determine the influence of fiber anisotropy and lack of perfect bond between fiber and matrix on the shear mode microbuckling. The experimental evaluation of the effect of various constituent and process characteristics on the behavior of these unidirectional composites in compression did not reveal any substantial increase in strength. However, theoretical evaluations indicate that the high degree of fiber anisotropy results in a significant drop in the predicted stress level for internal instability. Scanning electron microscope data analysis suggests that internal fiber failure and smooth surface debonding could be responsible for the measured low compressive strengths.

  7. Effects of quadriceps strength after static and dynamic whole-body vibration exercise.

    Science.gov (United States)

    Bush, Jill A; Blog, Gabriel L; Kang, Jie; Faigenbaum, Avery D; Ratamess, Nicholas A

    2015-05-01

    Numerous studies have shown performance benefits including whole-body vibration (WBV) as a training modality or an acute exercise protocol when used as a component of the resistance training program. Some studies have indicated that performing dynamic exercises as compared with static position exercises while exposed to WBV might be beneficial; however, evidence is lacking. Thus, the purpose of this study was to determine if an acute bout of dynamic versus static squats performed during WBV results in increase in quadriceps force production by means of dynamic isokinetic knee extension and flexion exercise. Nonresistance-trained healthy young men and women (N = 21) of 18-25 years participated in 4 protocols with 2-week rest in-between. Protocol 1 consisted of 5 sets of 10 dynamic squats without vibration; Protocol 2: 5 sets of 30-second static squats without vibration; Protocol 3: 5 sets of 10 dynamic squats with 30-Hz WBV for a total of 2.5 minutes; and Protocol 4: 5 sets of 30-second static squats with 30-Hz WBV for a total of 2.5 minutes. Prestrength tests (1 set of 4 repetitions at 100° · s(-1) for the knee extension exercise) was performed within 5 minutes of starting each protocol, and poststrength testing was performed within 1 minute of completing each protocol. Strength outcomes were analyzed by repeated measures analysis of variance with a significance level set at p ≤ 0.05. A significant decrease in strength was observed after dynamic and static squats without WBV (p = 0.002); an increase in strength after dynamic squats with WBV (p = 0.003); and a decrease in strength after static squats with WBV (p = 0.003). The inclusion of WBV to dynamic resistance exercise can be an added modality to increase strength. Whole-body vibration can have varied effects in altering muscle strength in untrained individuals according to the type of resistance training performed. As a dynamic squat with WBV seems to immediately potentiate neuromuscular functioning, the

  8. Upper body strength and power are associated with shot speed in men's ice hockey

    Directory of Open Access Journals (Sweden)

    Juraj Bežák

    2017-06-01

    Full Text Available Background: Recent studies that addressed shot speed in ice hockey have focused on the relationship between shot speed and variables such as a player's skills or hockey stick construction and its properties. There has been a lack of evidence that considers the relationship between shot speed and player strength, particularly in players at the same skill level. Objective: The aim of this study was to identify the relationship between maximal puck velocity of two shot types (the wrist shot and the slap shot and players' upper body strength and power. Methods: Twenty male professional and semi-professional ice hockey players (mean age 23.3 ± 2.4 years participated in this study. The puck velocity was measured in five trials of the wrist shot and five trials of the slap shot performed by every subject. All of the shots were performed on ice in a stationary position 11.6 meters in front of an electronic device that measures the speed of the puck. The selected strength and power variables were: muscle power in concentric contraction in the countermovement bench press with 40 kg and 50 kg measured with the FiTRODyne Premium device; bench press one-repetition maximum; and grip strength measured by digital hand dynamometer. Results: The correlations between strength/power variables and the puck velocity in the wrist shot and the slap shot ranged between .29-.72 and .16-.62, respectively. Puck velocities produced by wrist shots showed significant correlations with bench press muscle power with 40 kg (p = .004 and 50 kg (p < .001; and one-repetition maximum in bench press (p = .004. The slap shot puck velocity was significantly associated with bench press muscle power with 40 kg (p = .014 and 50 kg (p = .004. Conclusions: This study provides evidence that there are significant associations between shot speed and upper body strength and power.

  9. Estimating body weight and body composition of chickens by using noninvasive measurements.

    Science.gov (United States)

    Latshaw, J D; Bishop, B L

    2001-07-01

    The major objective of this research was to develop equations to estimate BW and body composition using measurements taken with inexpensive instruments. We used five groups of chickens that were created with different genetic stocks and feeding programs. Four of the five groups were from broiler genetic stock, and one was from sex-linked heavy layers. The goal was to sample six males from each group when the group weight was 1.20, 1.75, and 2.30 kg. Each male was weighed and measured for back length, pelvis width, circumference, breast width, keel length, and abdominal skinfold thickness. A cloth tape measure, calipers, and skinfold calipers were used for measurement. Chickens were scanned for total body electrical conductivity (TOBEC) before being euthanized and frozen. Six females were selected at weights similar to those for males and were measured in the same way. Each whole chicken was ground, and a portion of ground material of each was used to measure water, fat, ash, and energy content. Multiple linear regression was used to estimate BW from body measurements. The best single measurement was pelvis width, with an R2 = 0.67. Inclusion of three body measurements in an equation resulted in R2 = 0.78 and the following equation: BW (g) = -930.0 + 68.5 (breast, cm) + 48.5 (circumference, cm) + 62.8 (pelvis, cm). The best single measurement to estimate body fat was abdominal skinfold thickness, expressed as a natural logarithm. Inclusion of weight and skinfold thickness resulted in R2 = 0.63 for body fat according to the following equation: fat (%) = 24.83 + 6.75 (skinfold, ln cm) - 3.87 (wt, kg). Inclusion of the result of TOBEC and the effect of sex improved the R2 to 0.78 for body fat. Regression analysis was used to develop additional equations, based on fat, to estimate water and energy contents of the body. The body water content (%) = 72.1 - 0.60 (body fat, %), and body energy (kcal/g) = 1.097 + 0.080 (body fat, %). The results of the present study

  10. Repair bond strength of composite resin to sandblasted and laser irradiated Y-TZP ceramic surfaces.

    Science.gov (United States)

    Kirmali, Omer; Barutcigil, Çağatay; Ozarslan, Mehmet Mustafa; Barutcigil, Kubilay; Harorlı, Osman Tolga

    2015-01-01

    This study investigated the effects of different surface treatments on the repair bond strength of yttrium-stabilized tetragonal zirconia polycrystalline ceramic (Y-TZP) zirconia to a composite resin. Sixty Y-TZP zirconia specimens were prepared and randomly divided into six groups (n = 10) as follows: Group 1, surface grinding with Cimara grinding bur (control); Group 2, sandblasted with 30 µm silica-coated alumina particles; Group 3, Nd:YAG laser irradiation; Group 4, Er,Cr:YSGG laser irradiation; Group 5, sandblasted + Nd:YAG laser irradiation; and Group 6, sandblasted + Er,Cr:YSGG laser irradiation. After surface treatments, the Cimara(®) System was selected for the repair method and applied to all specimens. A composite resin was built-up on each zirconia surface using a cylindrical mold (5 × 3 mm) and incrementally filled. The repair bond strength was measured with a universal test machine. Data were analyzed using a one-way ANOVA and a Tukey HSD test (p = 0.05). Surface topography after treatments were evaluated by a scanning electron microscope (SEM). Shear bond strength mean values ranged from 15.896 to 18.875 MPa. There was a statistically significant difference between group 3 and the control group (p < 0.05). Also, a significant increase in bond strength values was noted in group 6 (p < 0.05). All surface treatment methods enhanced the repair bond strength of the composite to zirconia; however, there were no significant differences between treatment methods. The results revealed that Nd:YAG laser irradiation along with the combination of sandblasting and Er,Cr:YSGG laser irradiation provided a significant increase in bond strength between the zirconia and composite resin. © Wiley Periodicals, Inc.

  11. Effectiveness of exercise and protein supplementation intervention on body composition, functional fitness, and oxidative stress among elderly Malays with sarcopenia.

    Science.gov (United States)

    Shahar, Suzana; Kamaruddin, Norshafarina Shari; Badrasawi, Manal; Sakian, Noor Ibrahim Mohamed; Abd Manaf, Zahara; Yassin, Zaitun; Joseph, Leonard

    2013-01-01

    Sarcopenia, characterized as muscle loss that occurs with aging, is a major health problem in an aging population, due to its implications on mobility, quality of life, and fall risk. Protein supplementation could improve the physical fitness by increasing protein anabolism, and exercise has a documented evidence of positive effect on functional status among the elderly. However, the combined effect of both protein supplementation and exercise has not been investigated among sarcopenic elderly in the Asian population. Thus, this study aimed to determine the effectiveness of exercise intervention and protein supplementation either alone or in combination for 12 weeks, on body composition, functional fitness, and oxidative stress among elderly Malays with sarcopenia. Sixty five sarcopenic elderly Malays aged 60-74 years were assigned to the control group, exercise group (ExG), protein supplementation group (PrG), or the combination of exercise and protein supplementation group. A significant interaction effect between body weight and body mass index (BMI) was observed, with the PrG (-2.1% body weight, -1.8% BMI) showing the highest reductions. Further, there was a decrease in % body fat (-4.5%) and an increase in fat-free mass (kg) (+5.7%) in the ExG after 12 weeks (P exercise program was found to improve muscle strength and body composition, while protein supplementation reduced body weight and increased upper body strength, among sarcopenic elderly in Malaysia.

  12. Body Composition Evaluation Issue among Young Elite Football Players: DXA Assessment

    Directory of Open Access Journals (Sweden)

    César Leão

    2017-02-01

    Full Text Available Accurate assessment of body composition is an important issue among athletes. Different methodologies generate controversial results, leading to a deep uncertainty on individual exercise prescriptions. Thus, this study aims to identify the differences between field methods, such as bioelectrical impedance (BIA and skinfold assessment, with a clinical method, highly accurate, dual-energy X-ray absorptiometry (DXA, among elite young football players. Thirty-eight male football players with a mean (sd age of 16.7 (0.87 years, involved in the Portuguese national competition of U16 (n = 13 and U19 (n = 25, were evaluated and objective measures of body composition, muscle strength and football skills were collected by trained specialists. Body composition was assessed using BIA (Tanita BC-418, Tanita Corp., Tokyo, Japan, in agreement with all the evaluation premises. Additionally, all athletes were evaluated using the clinical method DXA (Hologic Inc., Waltham, MA, USA. Among the U19 athletes, three skinfold sites (SKF were assessed: chest, abdomin and thigh. The Spearman correlation coefficients and the mean difference between methods were calculated. The agreement between both methods was analyzed using Bland-Altman plots. Among the evaluated athletes, lower mean values of body fat % were found using BIA as a method of body composition assessment compared with DXA (12.05 vs. 15.58 for U16; 11.97 vs. 14.16 for U19. Despite the moderate correlation between methods (r = 0.33 to estimate the percentage of total fat, the median of the difference (DXA vs. BIA was relevant in clinical terms, with 2.90% and 1.47% for U16 and U19 athletes, respectively. Stronger correlations were found between the sum of the SKF and DXA fat estimation (r = 0.68. The Bland-Altman plots showed a clear underestimation in the evaluations using the BIA, namely among athletes with better body composition profiles (8%–12% of fat. Using BIA, an underestimation of body fat

  13. Effect of water curing duration on strength behaviour of portland composite cement (PCC) mortar

    Science.gov (United States)

    Caronge, M. A.; Tjaronge, M. W.; Hamada, H.; Irmawaty, R.

    2017-11-01

    Cement manufacturing of Indonesia has been introduced Portland Composite Cement (PCC) to minimize the rising production cost of cement which contains 80% clinker and 20% mineral admixture. A proper curing is very important when the cement contains mineral admixture materials. This paper reports the results of an experimental study conducted to evaluate the effect of water curing duration on strength behaviour of PCC mortar. Mortar specimens with water to cement ratio of (W/C) 0.5 were casted. Compressive strength, flexural strength and concrete resistance were tested at 7, 28 and 91 days cured water. The results indicated that water curing duration is essential to continue the pozzolanic reaction in mortar which contributes to the development of strength of mortar made with PCC.

  14. Strength and conductivity of unidirectional copper composites reinforced by continuous SiC fibers

    International Nuclear Information System (INIS)

    Kimmig, S.; Allen, I.; You, J.H.

    2013-01-01

    A SiC long fiber-reinforced copper composite offers a beneficial combination of high strength and high thermal conductivity at elevated temperatures. Both properties make the composite a promising material for the heat sink of high-heat-flux components. In this work, we developed a novel Cu/SiC f composite using the Sigma fiber. Based on HIP technique, a metallurgical process was established for fabricating high quality specimens using a TiC interface coating. Extensive tensile tests were conducted on the unidirectionally reinforced composite at 20 °C and 300 °C for a wide range of fiber volume fraction (V f ). In this paper, a large amount of test data is presented. The transversal thermal conductivity varies from 260 to 130 W/mK at 500 °C as V f is increased from 13% to 37%. The tensile strength reached up to 1246 MPa at 20 °C for V f = 37.6%, where the fracture strain was limited to 0.8%. The data of both elastic modulus and ultimate strength exhibited a good agreement with the rule-of-mixture predictions indicating a high quality of the materials. The strength of the composite with the Sigma fibers turned out to be superior to those of the SCS6 fibers at 300 °C, although the SCS6 fiber actually has a higher strength than the Sigma fiber. The fractographic pictures of tension test and fiber push-out test manifested a sufficient interfacial bonding

  15. Comparative study to evaluate shear bond strength of RMGIC to composite resin using different adhesive systems

    Directory of Open Access Journals (Sweden)

    Manoj G Chandak

    2012-01-01

    Full Text Available Aim: The aim of the study is to compare and evaluate the role of new dental adhesives to bond composite to the resinmodified glass inomer cement (RMGIC. Materials and Methods: Thirty specimens were prepared on acrylic blocks, with wells prepared in it by drilling holes, to retain the RMGIC. The specimens were randomly divided into three groups of ten specimens each. In Group a thin layer of selfetch adhesive (3M ESPE was applied between the RMGIC and the composite resin FILTEK P60 (3M SPE. In Group II, total etch adhesive (Adeper Scotch bond 2, 3M ESPE was applied, and in Group III, there was no application of any adhesive between RMGIC and the composite resin. After curing all the specimens, the shear bond strength was measured using an Instron universal testing machine. Results: The results were drawn and tabulated using ANOVA-fishers and Dunnet D statistical tests.The maximum shear bond strength values were recorded in Group I specimens with self-etch adhesive showing a mean value of 2.74 when compared to the Group II adhesive (Total etch showing a mean shear strength of value 1.89, where no adhesive was used, showed a minimum mean shear bond strength of 1.42. There was a great and significant difference between Group I and Group II (P value 0.05 whereas, both Group I and Group II showed a vast and significant difference from Group III (P value = 0-001. Conclusion: Hence, this present study concludes that application of self-etch adhesive (3M ESPE, U.S.A in between RMGIC and composite resin increases the shear bond strength between RMGIC and the resin composites, as compared to the total-etch type adhesive (Adeper Scotch bond 2,3M ESPE, U.S.A as well as without application of the adhesive agent.

  16. Repair bond strength of nanohybrid composite resins with a universal adhesive.

    Science.gov (United States)

    Altinci, Pinar; Mutluay, Murat; Tezvergil-Mutluay, Arzu

    2018-01-01

    Objective: To investigate the repair bond strength of fresh and aged nanohybrid and hybrid composite resins using a universal adhesive (UA). Materials and methods: Fresh and aged substrates were prepared using two nanohybrid (Venus Pearl, Heraus Kulzer; Filtek Supreme XTE, 3 M ESPE) and one hybrid (Z100, 3 M ESPE) composite resin, and randomly assigned to different surface treatments: (1) no treatment (control), (2) surface roughening with 320-grit (SR), (3) SR + UA (iBOND, Heraus Kulzer), (4) SR + Silane (Signum, Ceramic Bond I, Heraeus Kulzer) + UA, (5) SR + Sandblasting (CoJet, 3 M ESPE) + Silane + UA. After surface treatment, fresh composite resin was added to the substrates at 2 mm layer increments to a height of 5 mm, and light cured. Restored specimens were water-stored for 24 h and sectioned to obtain 1.0 × 1.0 mm beams ( n  = 12), and were either water-stored for 24 h at 37 °C, or water-stored for 24 h, and then thermocycled for 6000 cycles before microtensile bond strength (µTBS) testing. Data were analyzed with ANOVA and Tukey's HSD tests ( p  = .05). Results: Combined treatment of SR, sandblasting, silane and UA provided repair bond strength values comparable to the cohesive strength of each tested resin material ( p  composite resins upto 65% ( p  composite repair. Sandblasting and silane application slightly increases the repair strength for all substrate types.

  17. CHILES, Singularity Strength of Linear Elastic Bodies by Finite Elements Method

    International Nuclear Information System (INIS)

    Benzley, S.E.; Beisinger, Z.E.

    1981-01-01

    1 - Description of problem or function: CHILES is a finite element computer program that calculates the strength of singularities in linear elastic bodies. Plane stress, plane strain, and axisymmetric conditions are treated. Crack tip singularity problems are solved by this version of the code, but any type of integrable singularity may be properly modeled by modifying selected subroutines in the program. 2 - Method of solution: A generalized, quadrilateral finite element that includes a singular point at a corner node is incorporated in the code. The displacement formulation is used and inter-element compatibility is maintained so that monotone convergence is preserved. 3 - Restrictions on the complexity of the problem: CHILES allows three singular points to be modeled in the body being analyzed and each singular point may have coupled Mode I and II deformations. 1000 nodal points may be used

  18. The independent association between diet quality and body composition.

    Science.gov (United States)

    Drenowatz, Clemens; Shook, Robin P; Hand, Gregory A; Hébert, James R; Blair, Steven N

    2014-05-12

    Excess body weight is associated with an imbalance between energy expenditure and dietary intake but evidence on the association between diet quality and body composition remains equivocal. Rather than relying on differences in diet quality between overweight/obese and normal weight adults, this study examined the association between the Healthy Eating Index 2010 (HEI-2010) and body fatness on a continuous scale, independent of physical activity (PA). Further the association between components of the HEI-2010 and risk for overweight/obesity was explored. 407 adults (27.6 ± 3.7 years) provided at least two 24-hour diet recalls over a period of 14 days, which were used to calculate the HEI-2010. Percent body fat (BF) was assessed via dual X-ray absorptiometry and PA was determined via a multi-sensor device, worn over a period of 10 days. PA was a stronger contributor to the variability in BF than the HEI-2010 and the association between HEI-2010 and BF was significant only in men. Particularly a high consumption of protein, sodium and empty calories increased the risk for overweight/obesity. Adherence to dietary guidelines positively affects body fatness in men, independent of PA. In contrast to current dietary recommendations, the risk for overweight/obesity was increased with a higher protein intake.

  19. Environment-friendly wood fibre composite with high bonding strength and water resistance

    Science.gov (United States)

    Ji, Xiaodi; Dong, Yue; Nguyen, Tat Thang; Chen, Xueqi; Guo, Minghui

    2018-04-01

    With the growing depletion of wood-based materials and concerns over emissions of formaldehyde from traditional wood fibre composites, there is a desire for environment-friendly binders. Herein, we report a green wood fibre composite with specific bonding strength and water resistance that is superior to a commercial system by using wood fibres and chitosan-based adhesives. When the mass ratio of solid content in the adhesive and absolute dry wood fibres was 3%, the bonding strength and water resistance of the wood fibre composite reached the optimal level, which was significantly improved over that of wood fibre composites without adhesive and completely met the requirements of the Chinese national standard GB/T 11718-2009. Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) characterizations revealed that the excellent performance of the binder might partly be due to the amide linkages and hydrogen bonding between wood fibres and the chitosan-based adhesive. We believe that this strategy could open new insights into the design of environment-friendly wood fibre composites with high bonding strength and water resistance for multifunctional applications.

  20. Normalisation of body composition parameters for nutritional assessment

    International Nuclear Information System (INIS)

    Preston, Thomas

    2014-01-01

    Full text: Normalisation of body composition parameters to an index of body size facilitates comparison of a subject’s measurements with those of a population. There is an obvious focus on indexes of obesity, but first it is informative to consider Fat Free Mass (FFM) in the context of common anthropometric measures of body size namely, height and weight. The contention is that FFM is a more physiological measure of body size than body mass. Many studies have shown that FFM relates to height ^p. Although there is debate over the appropriate exponent especially in early life, it appears to lie between 2 and 3. If 2, then FFM Index (FFMI; kg/m2) and Fat Mass Index (FMI; kg/m2) can be summed to give BMI. If 3 were used as exponent, then FFMI (kg/m3) plus FMI (kg/m3) gives the Ponderal Index (PI; weight/height3). In 2013, Burton argued that that a cubic exponent is appropriate for normalisation as it is a dimensionless quotient. In 2012, Wang and co-workers repeated earlier observations showing a strong linear relationship between FFM and height3. The importance of the latter study comes from the fact that a 4 compartment body composition model was used, which is recognised as the most accurate means of describing FFM. Once the basis of a FFMI has been defined it can be used to compare measurements with those of a population, either directly, as a ratio to a norm or as a Z-score. FFMI charts could be developed for use in child growth. Other related indexes can be determined for use in specific circumstances such as: body cell mass index (growth and wasting); skeletal muscle mass index (SMMI) or appendicular SMMI (growth and sarcopenia); bone mineral mass index (osteoporosis); extracellular fluid index (hydration). Finally, it is logical that the same system is used to define an adiposity index, so Fat Mass Index (FMI; kg/height3) can be used as it is consistent with FFMI (kg/height3) and PI. It should also be noted that the index FM/FFM, describes an individual

  1. Host genetic variation impacts microbiome composition across human body sites.

    Science.gov (United States)

    Blekhman, Ran; Goodrich, Julia K; Huang, Katherine; Sun, Qi; Bukowski, Robert; Bell, Jordana T; Spector, Timothy D; Keinan, Alon; Ley, Ruth E; Gevers, Dirk; Clark, Andrew G

    2015-09-15

    The composition of bacteria in and on the human body varies widely across human individuals, and has been associated with multiple health conditions. While microbial communities are influenced by environmental factors, some degree of genetic influence of the host on the microbiome is also expected. This study is part of an expanding effort to comprehensively profile the interactions between human genetic variation and the composition of this microbial ecosystem on a genome- and microbiome-wide scale. Here, we jointly analyze the composition of the human microbiome and host genetic variation. By mining the shotgun metagenomic data from the Human Microbiome Project for host DNA reads, we gathered information on host genetic variation for 93 individuals for whom bacterial abundance data are also available. Using this dataset, we identify significant associations between host genetic variation and microbiome composition in 10 of the 15 body sites tested. These associations are driven by host genetic variation in immunity-related pathways, and are especially enriched in host genes that have been previously associated with microbiome-related complex diseases, such as inflammatory bowel disease and obesity-related disorders. Lastly, we show that host genomic regions associated with the microbiome have high levels of genetic differentiation among human populations, possibly indicating host genomic adaptation to environment-specific microbiomes. Our results highlight the role of host genetic variation in shaping the composition of the human microbiome, and provide a starting point toward understanding the complex interaction between human genetics and the microbiome in the context of human evolution and disease.

  2. Factors influencing the thermally-induced strength degradation of B/Al composites

    Science.gov (United States)

    Dicarlo, J. A.

    1983-01-01

    Literature data related to the thermally-induced strength degradation of B/Al composites were examined in the light of fracture theories based on reaction-controlled fiber weakening. Under the assumption of a parabolic time-dependent growth for the interfacial reaction product, a Griffith-type fracture model was found to yield simple equations whose predictions were in good agreement with data for boron fiber average strength and for B/Al axial fracture strain. The only variables in these equations were the time and temperature of the thermal exposure and an empirical factor related to fiber surface smoothness prior to composite consolidation. Such variables as fiber diameter and aluminum alloy composition were found to have little influence. The basic and practical implications of the fracture model equations are discussed. Previously announced in STAR as N82-24297

  3. Factors influencing the thermally-induced strength degradation of B/Al composites

    International Nuclear Information System (INIS)

    Dicarlo, J.A.

    1983-01-01

    Literature data related to the thermally-induced strength degradation of B/Al composites were examined in the light of fracture theories based on reaction-controlled fiber weakening. Under the assumption of a parabolic time-dependent growth for the interfacial reaction product, a Griffith-type fracture model was found to yield simple equations whose predictions were in good agreement with data for boron fiber average strength and for B/Al axial fracture strain. The only variables in these equations were the time and temperature of the thermal exposure and an empirical factor related to fiber surface smoothness prior to composite consolidation. Such variables as fiber diameter and aluminum alloy composition were found to have little influence. The basic and practical implications of the fracture model equations are discussed

  4. Fibre-matrix bond strength studies of glass, ceramic, and metal matrix composites

    Science.gov (United States)

    Grande, D. H.; Mandell, J. F.; Hong, K. C. C.

    1988-01-01

    An indentation test technique for compressively loading the ends of individual fibers to produce debonding has been applied to metal, glass, and glass-ceramic matrix composites; bond strength values at debond initiation are calculated using a finite-element model. Results are correlated with composite longitudinal and interlaminar shear behavior for carbon and Nicalon fiber-reinforced glasses and glass-ceramics including the effects of matrix modifications, processing conditions, and high-temperature oxidation embrittlement. The data indicate that significant bonding to improve off-axis and shear properties can be tolerated before the longitudinal behavior becomes brittle. Residual stress and other mechanical bonding effects are important, but improved analyses and multiaxial interfacial failure criteria are needed to adequately interpret bond strength data in terms of composite performance.

  5. Composite slab behavior and strength analysis under static and dynamic loads

    Directory of Open Access Journals (Sweden)

    Florin Radu HARIGA

    2012-07-01

    Full Text Available Steel-framed buildings are typically constructed using steel-deck-reinforced concrete floor slabs. The in-plane (or diaphragm strength and stiffness of the floor system are frequently utilized in the lateral load-resisting system design. This paper presents the results of an experimental research program in which four full size composite diaphragms were vertically loaded to the limit state, under static or dynamic loads. Two test specimens were provided with longitudinal steel-deck ribs, and the other two specimens with cross steel-deck ribs. Typical composite diaphragm limit states are described, and the controlling limit state for each of the full size tests is indicated. The interaction effects between the reinforced concrete slab and the steel girder on the composite slab strength and stiffness were mainly studied.

  6. The association between calcium consumption and students body composition

    Directory of Open Access Journals (Sweden)

    Przemysław Zając

    2017-09-01

    Full Text Available Introduction: The consumption of calcium in the Polish population is insufficient, which may negatively influence the occurrence of osteoporosis, as well as cause overweight and obesity. Aim of the research : To analyse the relationship between calcium consumption and body composition of the participants of this study. Material and methods : The study was carried out on a sample group of 103 nursing students. The study group consisted of 91 (88.3% women and 12 (11.7% men, aged from 19 to 33 years. The participants of the study had their body composition analysed, the body mass index (BMI was calculated, and the authors carried out a survey involving the Dairy Products Frequency Questionnaire (ADOS-Ca as well as their own questionnaire to evaluate the socio-economic status of the subjects. Results : The students who had the lowest calcium consumption also had the lowest BMI (p = 0.0015 and the lowest amount of visceral fat (p = 0.0260. Individuals who consumed the lowest amount of calcium also had the lowest muscle mass (p = 0.007 and bone mass (p = 0.004. However, the authors did not notice a significant statistical difference between the level of calcium consumption and the percentage of adipose tissue (p = 0.5000 as well as body water percentage (p = 0.3200. Conclusions: The results of the research do not confirm the hypothesis that high calcium consumption is associated with a lower probability of the occurrence of excess body mass and adipose tissue.

  7. TREATMENT OF SUBCLINICAL HYPERTHYROIDISM: EFFECT ON BODY COMPOSITION.

    Science.gov (United States)

    Boj-Carceller, Diana; Sanz-París, Alejandro; Sánchez-Oriz, Enrique; García-Foncillas López, Rafael; Calmarza-Calmarza, Pilar; Blay-Cortes, Vicente; Abós-Olivares, Ma Dolores

    2015-11-01

    subclinical hyperthyroidism (SHT) is associated with harmful effects on cardiovascular system, bone metabolism and progression to clinical hyperthyroidism. Loss of weight is a common fact in patients with clinical hyperthyroidism and of particular relevance in elderly patients. to assess changes in body composition after radioiodine therapy for SHT due to toxic nodular goiter. prospective controlled cohort study. Patients with persistent SHT due to toxic nodular goiter were purposed to receive treatment with radioiodine (treatment group) or to delay treatment until the study was over (control group). All treated patients received 555 MBq of ¹³¹I. Body composition (lean mass, fat mass and bone mineral content) was determined by dual-energy X-ray absorptiometry (DEXA) at baseline and 12 months after. twenty-nine patients were studied (age 69.5 ± 11.5; 75.9% women; BMI 27.1 ± 5.7 kg/m²; serum thyrotropin (TSH) 0.20 ± 0.21 μUI/mL; serum free thyroxine (T4) 1.01 ± 0.19 ng/dL), 17 belonging to the treatment group and 12 to the control group. Study groups were comparable, although there was a trend for the treatment group to have more fat mass. No longitudinal changes in body composition were noted in either group, except for a trend to gain fat mass. However, when individuals with age > 65 years were selected, only patients who received radioiodine therapy showed a significant increase in body weight (from 64.1 ± 10.0 to 66.9 ± 9.2 kg), BMI (from 27.3 ± 4.8 to 28.7 ± 4.5 kg/m²), fat mass (from 26.1 ± 8.5 to 27.8 ± 7.9 kg), lean mass (from 36.3 ± 0.4 to 37.4 ± 0.4 kg) and skeletal muscle mass index (SMI) (from 6.0 ± 0.6 to 6.3 ± 0.6 kg/m²). treatment of SHT has impact on body composition in subjects older than 65 years. Weight gain reflects increases in fat and, more interestingly, in lean mass. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  8. Effect of different surface treatments on the shear bond strength of nanofilled composite repairs

    Directory of Open Access Journals (Sweden)

    Ghazaleh Ahmadizenouz

    2016-03-01

    Full Text Available Background. Repairing aged composite resin is a challenging process. Many surface treatment options have been proposed to this end. This study evaluated the effect of different surface treatments on the shear bond strength (SBS of nano-filled composite resin repairs. Methods. Seventy-five cylindrical specimens of a Filtek Z350XT composite resin were fabricated and stored in 37°C distilled water for 24 hours. After thermocycling, the specimens were divided into 5 groups according to the following surface treatments: no treatment (group 1; air abrasion with 50-μm aluminum oxide particles (group 2; irradiation with Er:YAG laser beams (group 3; roughening with coarse-grit diamond bur + 35% phosphoric acid (group 4; and etching with 9% hydrofluoric acid for 120 s (group 5. Another group of Filtek Z350XT composite resin samples (4×6 mm was fabricated for the measurement of cohesive strength (group 6. A silane coupling agent and an adhesive system were applied after each surface treatment. The specimens were restored with the same composite resin and thermocycled again. A shearing force was applied to the interface in a universal testing machine. Data were analyzed using one-way ANOVA and post hoc Tukey tests (P < 0.05. Results. One-way ANOVA indicated significant differences between the groups (P < 0.05. SBS of controls was significantly lower than the other groups; differences between groups 2, 3, 4, 5 and 6 were not significant. Surface treatment with diamond bur + 35% phosphoric acid resulted in the highest bond strength. Conclusion. All the surface treatments used in this study improved the shear bond strength of nanofilled composite resin used.

  9. New reusable elastomer electrodes for assessing body composition

    International Nuclear Information System (INIS)

    Moreno, M-V; Chaset, L; Bittner, P A; Barthod, C; Passard, M

    2013-01-01

    The development of telemedicine requires finding solutions of reusable electrodes for use in patients' homes. The objective of this study is to evaluate the relevance of reusable elastomer electrodes for measuring body composition. We measured a population of healthy Caucasian (n = 17). A measurement was made with a reference device, the Xitron®, associated with AgCl Gel electrodes (Gel) and another measurement with a multifrequency impedancemeter Z-Metrix® associated with reusable elastomer electrodes (Elast). We obtained a low variability with an average error of repeatability of 0.39% for Re and 0.32% for Rinf. There is a non significantly difference (P T-test > 0.1) about 200 ml between extracellular water Ve measured with Gel and Elast in supine and in standing position. For total body water Vt, we note a non significantly difference (P T-test > 0.1) about 100 ml and 2.2 1 respectively in supine and standing position. The results give low dispersion, with R 2 superior to 0.90, with a 1.5% maximal error between Gel and Elast on Ve in standing position. It looks possible, taking a few precautions, using elastomer electrodes for assessing body composition.

  10. Microshear bond strength of preheated silorane- and methacrylate-based composite resins to dentin.

    Science.gov (United States)

    Demirbuga, Sezer; Ucar, Faruk Izzet; Cayabatmaz, Muhammed; Zorba, Yahya Orcun; Cantekin, Kenan; Topçuoğlu, Hüseyin Sinan; Kilinc, Halil Ibrahim

    2016-01-01

    The aim of this study was to investigate the effect of preheating on microshear bond strength (MSBS) of silorane and methacrylate-based composite resins to human dentin. The teeth were randomly divided into three main groups: (1) composite resins were heated upto 68 °C; (2) cooled to 4 °C; and (3) control [room temperature (RT)]. Each group was then randomly subdivided into four subgroups according to adhesive system used [Solobond M (Voco), All Bond SE (Bisco), Clearfil SE Bond (CSE) (Kuraray), Silorane adhesive system (SAS) (3M ESPE)]. Resin composite cylinders were formed (0.9 mm diameter × 0.7 mm length) and MSBS of each specimen was tested. The preheated groups exhibited the highest MSBS (p composite resins may be an alternative way to increase the MSBS of composites on dentin. © Wiley Periodicals, Inc.

  11. Comparison of two software versions for assessment of body-composition analysis by DXA

    DEFF Research Database (Denmark)

    Vozarova, B; Wang, J; Weyer, C

    2001-01-01

    To compare two software versions provided by Lunar CO: for assessment of body composition analysis by DXA.......To compare two software versions provided by Lunar CO: for assessment of body composition analysis by DXA....

  12. Measuring body composition and energy expenditure in children with severe neurologic impairment and intellectual disability

    NARCIS (Netherlands)

    Rieken, Rob; van Goudoever, Johannes B.; Schierbeek, Henk; Willemsen, Sten P.; Calis, Elsbeth A. C.; Tibboel, Dick; Evenhuis, Heleen M.; Penning, Corine

    2011-01-01

    Accurate prediction equations for estimating body composition and total energy expenditure (TEE) in children with severe neurologic impairment and intellectual disability are currently lacking. The objective was to develop group-specific equations to predict body composition by using

  13. Different Short-Term Mild Exercise Modalities Lead to Differential Effects on Body Composition in Healthy Prepubertal Male Rats

    Directory of Open Access Journals (Sweden)

    D. M. Sontam

    2015-01-01

    Full Text Available Physical activity has a vital role in regulating and improving bone strength. Responsiveness of bone mass to exercise is age dependent with the prepubertal period suggested to be the most effective stage for interventions. There is a paucity of data on the effects of exercise on bone architecture and body composition when studied within the prepubertal period. We examined the effect of two forms of low-impact exercise on prepubertal changes in body composition and bone architecture. Weanling male rats were assigned to control (CON, bipedal stance (BPS, or wheel exercise (WEX groups for 15 days until the onset of puberty. Distance travelled via WEX was recorded, food intake measured, and body composition quantified. Trabecular and cortical microarchitecture of the femur were determined by microcomputed tomography. WEX led to a higher lean mass and reduced fat mass compared to CON. WEX animals had greater femoral cortical cross-sectional thickness and closed porosity compared to CON. The different exercise modalities had no effect on body weight or food intake, but WEX significantly altered body composition and femoral microarchitecture. These data suggest that short-term mild voluntary exercise in normal prepubertal rats can alter body composition dependent upon the exercise modality.

  14. Dehydroepiandrosterone Supplementation Combined with Whole-Body Vibration Training Affects Testosterone Level and Body Composition in Mice.

    Science.gov (United States)

    Chen, Wen-Chyuan; Chen, Yi-Ming; Huang, Chi-Chang; Tzeng, Yen-Dun

    2016-01-01

    Dehydroepiandrosterone (DHEA), the most abundant sex steroid, is primarily secreted by the adrenal gland and a precursor hormone used by athletes for performance enhancement. Whole-body vibration (WBV) is a well-known light-resistance exercise by automatic adaptations to rapid and repeated oscillations from a vibrating platform, which is also a simple and convenient exercise for older adults. However, the potential effects of DHEA supplementation combined with WBV training on to body composition, exercise performance, and hormone regulation are currently unclear. The objective of the study is to investigate the effects of DHEA supplementation combined with WBV training on body composition, exercise performance, and physical fatigue-related biochemical responses and testosterone content in young-adult C57BL/6 mice. In this study, male C57BL/6 mice were divided into four groups (n = 8 per group) for 6-weeks treatment: sedentary controls with vehicle (SC), DHEA supplementation (DHEA, 10.2 mg/kg), WBV training (WBV; 5.6 Hz, 2 mm, 0.13 g), and WBV training with DHEA supplementation (WBV+DHEA; WBV: 5.6 Hz, 2 mm, 0.13 g and DHEA: 10.2 mg/kg). Exercise performance was evaluated by forelimb grip strength and exhaustive swimming time, as well as changes in body composition and anti-fatigue levels of serum lactate, ammonia, glucose, creatine kinase (CK), and blood urea nitrogen (BUN) after a 15-min swimming exercise. In addition, the biochemical parameters and the testosterone content were measured at the end of the experiment. Six-week DHEA supplementation alone significantly increased mice body weight (BW), muscle weight, testosterone level, and glycogen contents (liver and muscle) when compared with SC group. DHEA supplementation alone had no negative impact on all tissue and biochemical profiles, but could not improve exercise performance. However, WBV+DHEA supplementation also significantly decreased BW, testosterone level and glycogen content of liver, as well as serum

  15. Diametral tensile strength of two dental composites when immersed in ethanol, distilled water and artificial saliva.

    Science.gov (United States)

    Rehman, Abdur; Amin, Faiza; Abbas, Muhammad

    2014-11-01

    To examine the effect of distilled water, artificial saliva and ethanol on the tensile strength of direct tooth-coloured restorative material. The study was conducted at Dr. Ishrat ul Ebad Khan Institute of Oral Health Sciences, Dow University of Health Sciences (DUHS), Karachi, from April 2011 to September 2012. The testing was performed at the Pakistan Council of Scientific and Industrial Research (PCSIR) laboratories. Two composite resins Filtek Z250 and Spectrum TPH were tested. Specimens (13 mm x 3 mm x 2 mm) of each material were prepared in the stainless steel mould according to the manufacturers' instructions and distributed into 3 equal groups: one immersed in distilled water, the other in artificial saliva, and the last one in ethanol for 24 hours. Tensile strength was determined after 24 hours in universal Instron Testing Machine. There were 72 specimens in all; 36 (50%) each for Filtek Z250 and Spectrum TPH. The three sub-groups in each case had 12 (33.3%) specimens. For the Filtek Z250, there was no statistically significant difference between immersion in distilled water and artificial saliva, but the ethanol group presented lower tensile strength (ptensile strength compared to distilled water (ptested composite resins were affected by the immersion media and adversely affected the mechanical properties of composite resins.

  16. Enhanced Flexural Strength of Tellurium Nanowires/epoxy Composites with the Reinforcement Effect of Nanowires

    Science.gov (United States)

    Balguri, Praveen Kumar; Harris Samuel, D. G.; Aditya, D. B.; Vijaya Bhaskar, S.; Thumu, Udayabhaskararao

    2018-02-01

    Investigating the mechanical properties of polymer nanocomposite materials has been greatly increased in the last decade. In particular, flexural strength plays a major role in resisting bending and shear loads of a composite material. Here, one dimensional (1D) tellurium nanowires (TeNWs) reinforced epoxy composites have been prepared and the flexural properties of resulted TeNWs/epoxy nanocomposites are studied. The diameter and length of the TeNWs used to make TeNWs/epoxy nanocomposites are 21±2.5 nm and 697±87 nm, respectively. Plain and TeNWs/epoxy nanocomposites are characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). Furthermore, significant enhancement in the flexural strength of TeNWs/epoxy nanocomposite is observed in comparison to plain epoxy composite, i.e. flexural strength is increased by 65% with the addition of very little amount of TeNWs content (0.05 wt.%) to epoxy polymer. Structural details of plain and TeNWs/epoxy at micrometer scale were examined by scanning electron microscopy (SEM). We believe that our results provide a new type of semiconductor nanowires based high strength epoxy polymer nanocomposites.

  17. Effect of Two-minute Application of 35% Sodium Ascorbate on Composite Bond Strength following Bleaching.

    Science.gov (United States)

    Ismail, Eman H; Kilinc, Evren; Hardigan, Patrick C; Rothrock, James K; Thompson, Jeffrey Y; Garcia-Godoy, Cristina

    2017-10-01

    The aim of this study is to assess the effect of 35% sodium ascorbate on microtensile bond strength of dentin immediately after bleaching with 35% hydrogen peroxide. A total of 25 sound human 3 rd molars were collected. Teeth were randomly divided into five groups for different treatments: Group I [bleaching + immediate bonding (i.e., restoration)], group II (bleaching + delayed bonding), group III (bleaching + sodium ascorbate + immediate bonding), group IV (bleaching + sodium ascorbate + delayed bonding), and group V (bonding only). After bleaching, but before bonding, groups II and IV were stored for 1 week in deionized water at 37°C. All samples were bonded using OptiBoned FL (Kerr) and Filtek Supreme (3M/ESPE). Teeth were sectioned into 1 × 1 mm 2 bars, and microtensile bond strength was tested with a universal testing machine (Instron 8841) at a cross-head speed of 0.5 mm/minute. Microtensile bond strength differed significantly across the five groups, with a significant reduction in microtensile bond strength observed for samples in group I relative to samples in any of the other treatment groups (p bleaching on composite bonding strength to dentin. The negative effects of bleaching on composite bonding can be neutralized by the application of the reversing agent sodium ascorbate thus, increasing the efficiency of clinic chair time. This is clinically relevant for those patients requiring restorative treatment immediately after in-office bleaching.

  18. Effect of newer antioxidants on the bond strength of composite on bleached enamel

    Directory of Open Access Journals (Sweden)

    M Manoharan

    2016-01-01

    Full Text Available Aim: The study aims to evaluate the effect of the application of two antioxidants on the bond strength of composite resin to bleached enamel. Materials and Methods: Eighty enamel surfaces were obtained from forty human extracted premolars. Specimens were randomly divided into four groups (n = 20. Group 1: No bleaching (control; Group 2a: Bleaching with 15% carbamide peroxide gel; Group 2b: Bleaching, followed by application of 10% sodium ascorbate gel; Group 2c: Bleaching, followed by application of 5% proanthocyanidin agent. Surfaces were etched followed by application of total etch bonding system, and composite resin cylinders were bonded. Specimens were tested for shear bond strength. Statistical Analysis Used: One-way analysis of variance was used for multiple group comparison and post hoc Tukey′s test for individual group-wise comparison. Results: Significantly higher shear bond strength values were observed in Group 2c and 2b as compared with Group 1 and 2a (P < 0.05. Among the antioxidants, Group 2c showed significantly higher shear bond strength values than Group 2b (P < 0.05. Conclusion: It can be concluded that the use of antioxidant before bonding procedures on bleached enamel completely neutralizes the deleterious effects of bleaching and increases the bond strength significantly.

  19. Body composition and physical fitness in women with bulimia nervosa or binge‐eating disorder

    Science.gov (United States)

    Rosenvinge, Jan H.; Friborg, Oddgeir; Pettersen, Gunn; Stensrud, Trine; Hansen, Bjørge Herman; Underhaug, Karoline E.; Teinung, Elisabeth; Vrabel, KariAnne; Svendsen, Mette; Bratland‐Sanda, Solfrid; Sundgot‐Borgen, Jorunn

    2018-01-01

    Abstract Objective Knowledge about physical fitness in women with bulimia nervosa (BN) or binge‐eating disorder (BED) is sparse. Previous studies have measured physical activity largely through self‐report, and physical fitness variables are mainly restricted to body mass index (BMI) and bone mineral density. We expanded the current knowledge in these groups by including a wider range of physical fitness indicators and objective measures of physical activity, assessed the influence of a history of anorexia nervosa (AN), and evaluated predictive variables for physical fitness. Method Physical activity, blood pressure, cardiorespiratory fitness (CRF), muscle strength, body composition, and bone mineral density were measured in 156 women with BN or BED, with mean (SD) age 28.4 years (5.7) and BMI 25.3 (4.8) kg m−2. Results Level of physical activity was higher than normative levels, still <50% met the official physical activity recommendation. Fitness in women with BN were on an average comparable with recommendations or normative levels, while women with BED had lower CRF and higher BMI, VAT, and body fat percentage. We found 10–12% with masked obesity. A history of AN did not predict current physical fitness, still values for current body composition were lower when comparing those with history of AN to those with no such history. Discussion Overall, participants with BN or BED displayed adequate physical fitness; however, a high number had unfavorable CRF and body composition. This finding calls for inclusion of physical fitness in routine clinical examinations and guided physical activity and dietary recommendations in the treatment of BN and BED. PMID:29473191

  20. Body composition and physical fitness in women with bulimia nervosa or binge-eating disorder.

    Science.gov (United States)

    Mathisen, Therese Fostervold; Rosenvinge, Jan H; Friborg, Oddgeir; Pettersen, Gunn; Stensrud, Trine; Hansen, Bjørge Herman; Underhaug, Karoline E; Teinung, Elisabeth; Vrabel, KariAnne; Svendsen, Mette; Bratland-Sanda, Solfrid; Sundgot-Borgen, Jorunn

    2018-04-01

    Knowledge about physical fitness in women with bulimia nervosa (BN) or binge-eating disorder (BED) is sparse. Previous studies have measured physical activity largely through self-report, and physical fitness variables are mainly restricted to body mass index (BMI) and bone mineral density. We expanded the current knowledge in these groups by including a wider range of physical fitness indicators and objective measures of physical activity, assessed the influence of a history of anorexia nervosa (AN), and evaluated predictive variables for physical fitness. Physical activity, blood pressure, cardiorespiratory fitness (CRF), muscle strength, body composition, and bone mineral density were measured in 156 women with BN or BED, with mean (SD) age 28.4 years (5.7) and BMI 25.3 (4.8) kg m -2 . Level of physical activity was higher than normative levels, still <50% met the official physical activity recommendation. Fitness in women with BN were on an average comparable with recommendations or normative levels, while women with BED had lower CRF and higher BMI, VAT, and body fat percentage. We found 10-12% with masked obesity. A history of AN did not predict current physical fitness, still values for current body composition were lower when comparing those with history of AN to those with no such history. Overall, participants with BN or BED displayed adequate physical fitness; however, a high number had unfavorable CRF and body composition. This finding calls for inclusion of physical fitness in routine clinical examinations and guided physical activity and dietary recommendations in the treatment of BN and BED. © 2018 The Authors International Journal of Eating Disorders Published by Wiley Periodicals, Inc.

  1. A novel multi-responsive polyampholyte composite hydrogel with excellent mechanical strength and rapid shrinking rate.

    Science.gov (United States)

    Xu, Kun; Tan, Ying; Chen, Qiang; An, Huiyong; Li, Wenbo; Dong, Lisong; Wang, Pixin

    2010-05-15

    Series of hydrophilic core-shell microgels with cross-linked poly(N-isopropylacrylamide) (PNIPAAm) as core and poly(vinyl amine) (PVAm) as shell are synthesized via surfactant-free emulsion polymerization. Then, the microgels are treated with a small amount of potassium persulfate (KPS) to generate free radicals on the amine nitrogens of PVAm, which subsequently initiate the graft copolymerization of acrylic acid (AA), acryloyloxyethyl trimethyl ammonium chloride (DAC), and acrylamide (AAm) onto microgels to prepare multi-responsive composite hydrogels. The composite hydrogels consist of cross-linked ungrafted polyampholyte chains as the first network and microgels with grafted polyampholyte chains as graft point and second network and show surprising mechanical strength and rapid response rate. The investigation shows the compress strength of composite hydrogels is up to 17-30 MPa, which is 60-100 times higher than that of the hydrogel matrix. The composite hydrogel shows reversible switch of transmittance when traveling the lowest critical temperature (LCST) of microgels. When the composite hydrogel swollen in pH 2.86 solution at ambient condition is immersed into the pH 7.00 solution at 45 °C, a rapid dynamic shrinking can be observed. And the character time (τ) of shrinking dynamic of composite hydrogel is 251.9 min, which is less than that of hydrogel matrix (τ=2273.7 min). Copyright © 2010 Elsevier Inc. All rights reserved.

  2. Apparent interfacial shear strength of short-flax-fiber/starch acetate composites

    DEFF Research Database (Denmark)

    Andersons, J.; Modniks, J.; Joffe, R.

    2016-01-01

    The paper deals with an indirect industry-friendly method for identification of the interfacial shear strength (IFSS) in a fully bio-based composite. The IFSS of flax fiber/starch acetate is evaluated by a modified Bowyer and Bader method based on an analysis of the stress-strain curve of a short......-fiber-reinforced composite in tension. A shear lag model is developed for the tensile stress-strain response of short-fiber-reinforced composites allowing for an elastic-perfectly plastic stress transfer. Composites with different fiber volume fractions and a variable content of plasticizer have been analyzed. The apparent...... IFSS of flax/starch acetate is within the range of 5.5-20.5 MPa, depending on composition of the material. The IFSS is found to be greater for composites with a higher fiber loading and to decrease with increasing content of plasticizer. The IFSS is equal or greater than the yield strength of the neat...

  3. Body composition changes in female bodybuilders during preparation for competition.

    Science.gov (United States)

    van der Ploeg, G E; Brooks, A G; Withers, R T; Dollman, J; Leaney, F; Chatterton, B E

    2001-04-01

    To determine anthropometric and body composition changes in female bodybuilders during preparation for competition. There was an attempt to match subjects in the control and experimental groups for height and percentage body fat (%BF) for the initial test of this longitudinal study. Five competitive bodybuilders (-X +/- s.d.: 35.3 +/- 5.7 y; 167.3 +/- 3.7 cm; 66.38 +/- 6.30 kg; 18.3 +/- 3.5 %BF) and five athletic females (-X +/- s.d.: 30.9 +/- 13.0 y; 166.9 +/- 3.9 cm; 55.94 +/- 3.59 kg; 19.1 +/- 3.3 %BF) were recruited from advertisements in a bodybuilding newsletter and placed on sports centre noticeboards. The following measurements were conducted 12 weeks, 6 weeks and 3-5 d before the bodybuilders' competitions: anthropometric profile, body density by underwater weighing, total body water via deuterium dilution and bone mineral mass from a dual-energy X-ray absorptiometry scan. A combination of the last three measurements enabled the %BF to the determined by a four compartment model. A significant (P bodybuilders as they prepared for competition was primarily due to a reduction in fat mass (FM; -4.42 kg; 76.2%) as opposed to fat-free mass (FFM; -1.38 kg; 23.8%). The decreases in body mass and FM over the final 6 weeks were greater than those over the first 6 weeks. Their %BF decreased (P bodybuilders were accompanied by a significant decline (P bodybuilders presented with low %BFs at the start of the experiment, they still significantly decreased their body mass during the 12 week preparation for competition and most of this loss was due to a reduction in FM as opposed to FFM.

  4. Body image and body composition: comparisons of young male elite soccer players and controls.

    Science.gov (United States)

    Arroyo, Marta; Gonzalez-de-Suso, Jose Manuel; Sanchez, Celia; Ansotegui, Laura; Rocandio, Ana M

    2008-12-01

    The purpose of this study was to evaluate body composition and body image (perception and satisfaction) in a group of young elite soccer players and to compare the data with those of a control group (age and BMI matched). Participants were 56 volunteer males whose mean age and BMI were 19.6 (SD 1.3) years and 23.3 (SD 1.1) kg/m2, respectively. Results showed that soccer players have a higher lean mass and lower fat mass than controls. Moreover, body perception (difference between current and actual image) was more accurate in controls than in soccer players, and the results suggest a tendency for soccer players to aspire to have more muscle mass and body fat. Soccer players perceived an ideal image with significantly higher body-fat percentage than their current and actual images. There were no body-dissatisfaction differences between groups, however. Although the results are necessarily limited by the small sample size, the findings should be of interest to coaches of young elite soccer teams.

  5. Determination of composition of pozzolanic waste mixtures with optimized compressive strength

    Directory of Open Access Journals (Sweden)

    Nardi José Vidal

    2004-01-01

    Full Text Available The utilization of ceramic wastes with pozzolanic properties along with other compounds for obtaining new materials with cementating properties is an alternative for reducing the environmental pollution. The acceptance of these new products in the market demands minimal changes in mechanical properties according to its utilization. For a variable range of compositional intervals, attempts were made to establish limiting incorporation proportions that assure the achievement of minimum pre-established mechanical strength values in the final product. In this case minimum compressive strength value is 3,000 kPa. A simultaneous association of other properties is also possible.

  6. Energy expenditure, nutritional status, body composition and physical fitness of Royal Marines during a 6-month operational deployment in Afghanistan.

    Science.gov (United States)

    Fallowfield, Joanne L; Delves, Simon K; Hill, Neil E; Cobley, Rosalyn; Brown, Pieter; Lanham-New, Susan A; Frost, Gary; Brett, Stephen J; Murphy, Kevin G; Montain, Scott J; Nicholson, Christopher; Stacey, Michael; Ardley, Christian; Shaw, Anneliese; Bentley, Conor; Wilson, Duncan R; Allsopp, Adrian J

    2014-09-14

    Understanding the nutritional demands on serving military personnel is critical to inform training schedules and dietary provision. Troops deployed to Afghanistan face austere living and working environments. Observations from the military and those reported in the British and US media indicated possible physical degradation of personnel deployed to Afghanistan. Therefore, the present study aimed to investigate the changes in body composition and nutritional status of military personnel deployed to Afghanistan and how these were related to physical fitness. In a cohort of British Royal Marines (n 249) deployed to Afghanistan for 6 months, body size and body composition were estimated from body mass, height, girth and skinfold measurements. Energy intake (EI) was estimated from food diaries and energy expenditure measured using the doubly labelled water method in a representative subgroup. Strength and aerobic fitness were assessed. The mean body mass of volunteers decreased over the first half of the deployment ( - 4·6 (sd 3·7) %), predominately reflecting fat loss. Body mass partially recovered (mean +2·2 (sd 2·9) %) between the mid- and post-deployment periods (Penergy expenditure (mean 15 167 (sd 1883) kJ) measured in a subgroup of volunteers. However, despite the body mass loss, aerobic fitness and strength were well maintained. Nutritional provision for British military personnel in Afghanistan appeared sufficient to maintain physical capability and micronutrient status, but providing appropriate nutrition in harsh operational environments must remain a priority.

  7. Modeling strength loss in wood by chemical composition. Part I, An individual component model for southern pine

    Science.gov (United States)

    J. E. Winandy; P. K. Lebow

    2001-01-01

    In this study, we develop models for predicting loss in bending strength of clear, straight-grained pine from changes in chemical composition. Although significant work needs to be done before truly universal predictive models are developed, a quantitative fundamental relationship between changes in chemical composition and strength loss for pine was demonstrated. In...

  8. Body Composition in Adult Patients with Thalassemia Major

    Directory of Open Access Journals (Sweden)

    Marianna Vlychou

    2016-01-01

    Full Text Available Objective. To assess body composition in adult male and female patients with thalassemia major by dual-energy X-ray absorptiometry (DXA and to compare the findings with a group of healthy age-matched controls. Methods. Our study group included sixty-two patients (27 males, mean age 36 years, and 35 females, mean age 36.4 years and fifteen age-matched healthy controls. All patients had an established diagnosis of thalassemia major and followed a regular blood transfusion scheme since childhood and chelation treatment. Fat, lean, and bone mineral density (BMD were assessed with dual-energy X-ray absorptiometry. Ferritin levels and body mass index of all patients and controls were also recorded. Student t-test and Wilcoxon test were performed and statistical significance was set at p<0.05. Results. BMD and whole body lean mass are lower in both male and female adult patients compared with controls (p<0.01 in both groups, whereas whole body fat mass was found to have no statistically significant difference compared to controls. Regional trunk fat around the abdomen was found to be lower in male patients compared to controls (p=0.02. Conclusion. Severe bone loss and diminished lean mass are expected in adult male and female patients with thalassemia major. Fat changes seem to affect mainly male patients.

  9. Utilization of Local Ingredients for the Production of High-Early-Strength Engineered Cementitious Composites

    Directory of Open Access Journals (Sweden)

    Hanwen Deng

    2018-01-01

    Full Text Available The rapid repair and retrofitting of existing transportation infrastructure requires dimensional stability and ductile repair material that can obtain sufficiently high strength in a few hours to accommodate the large loading and deformation at an early age. Engineering cementitious composites (ECCs is a class representative of the new generation of high-performance fiber-reinforced cement-based composites (HPFRCC with medium fiber content. The unique properties of tremendous ductility and tight multiple crack behavior indicate that ECC can be used as an effective retrofit material. The wide application of this material in China will require the use of all local ingredients. In this study, based on Chinese domestic ingredients, including matrix materials and all fibers, high-early-strength ECC (HES-ECC was designed under the guidance of strain-hardening criterion of ECC. The matrix properties and fiber/matrix interfacial micromechanics properties were obtained from three-point-bending test and single-fiber pullout test. The mechanical properties of HES-ECC were achieved by direct tensile test. The experimental results show that HES-ECC was successfully developed by using all Chinese materials. When using the domestic PVA fiber at 2%, the strength requirement can be achieved but only a low ductility. When using the domestic PE fiber at 0.8%, the strength and deformation requirement both can be obtained. The HES-ECC developed in this study exhibited compressive strength of more than 25 MPa within 6 hours, and an ultimate tensile strength of 5-6 MPa and tensile strain capacity of 3-4% after 60 days. Moreover, the cost of using domestic fiber can be largely reduced compared with using imported fiber, up to 70%; it is beneficial to the promotion of these high-early-strength ECCs in the Chinese market.

  10. Microtensile bond strength of silorane-based composite specific adhesive system using different bonding strategies

    Directory of Open Access Journals (Sweden)

    Laura AlveBastos

    2015-02-01

    Full Text Available Objectives The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. Materials and Methods Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE, the specific self-etching adhesive system (Adhesive System P90, 3M ESPE was used with and without pre-etching (Pre-etching/Silorane and Silorane groups. Teeth restored with methacrylate based-composite (Filtek Z250, 3M ESPE were hybridized with the two-step self-etching system (Clearfil SE Bond, Kuraray, with and without pre-etching (Pre-etching/Methacrylate and Methacrylate groups, or three-step adhesive system (Adper Scotchbond Multi-Purpose, 3M ESPE (Three-step/Methacrylate group (n = 6. The restored teeth were sectioned into stick-shaped test specimens (1.0 × 1.0 mm, and coupled to a universal test machine (0.5 mm/min to perform microtensile testing. Results Pre-etching/Methacrylate group presented the highest bond strength values, with significant difference from Silorane and Three-step/Methacrylate groups (p < 0.05. However, it was not significantly different from Preetching/Silorane and Methacrylate groups. Conclusions Pre-etching increased bond strength of silorane-based composite specific adhesive system to dentin.

  11. Novel high-strength Fe-based composite materials with large plasticity

    Energy Technology Data Exchange (ETDEWEB)

    Werniewicz, Katarzna; Kuehn, Uta; Mattern, Norbert; Eckert, Juergen; Siegel, Uwe; Bartusch, Birgit; Schultz, Ludwig [IFW Dresden, P.O. Box 270116, D-01171 Dresden (Germany); Kulik, Tadeusz [Warsaw University of Technology, Faculty of Materials Science and Engineering (Poland)

    2007-07-01

    Among glass-forming alloy systems reported so far, Fe-based bulk metallic glasses play a special role. Compared to other amorphous alloys e.g. Zr-, Ti-based, such glasses show superior mechanical strength. However, due to the general brittleness their wider application as structural materials is strongly restricted. The alternative approach to overcome this defect is to design BMG composites. In this work we present a series of new Fe-Cr-Mo-Ga-(Si,C) composite materials derived from an Fe-Cr-Mo-Ga-C-P-B glassy alloy, with the aim to improve the ductility of this high-strength material. The effect of the composition and the phase formation on the resulting mechanical properties was investigated. It has been found that the formation of a complex microstructure, which essentially consists of soft Ga-rich dendrites embedded in a hard Cr- and Mo-rich matrix, leads to a material with excellent compressive mechanical properties. While the obtained values of true strength are comparable with data reported for Fe-Cr-Mo-Ga-C-P-B BMG, the values of true strain are greatly improved for investigated composites.

  12. Body mass index and body composition among rescue firefighters personnel in Selangor, Malaysia

    Science.gov (United States)

    Rahimi, Nor Atiqah; Sedek, Razalee; Teh, Arnida Hani

    2016-11-01

    Obesity is a major public health problem in general population and there is no exception for firefighters. This disorder is definitely a burden for firefighters as they needed to be physically fit in order to work in dangerous situation and extinguishing fires. The purposes of this study were to determine physical characteristics and body composition among Malaysian Firefighters (MF) and to explore their association. This cross-sectional study involved 330 rescue firefighters aged between 20-50 years old from nine different districts in Selangor conducted between August and November 2015. Anthropometric measurements included height, weight and waist circumference (WC). Body composition was measured using bioelectrical impedance. The mean height, weight, body mass index (BMI), WC and body fat percentage were 169.4±5.3 cm, 74.5±12.2 kg, 25.9±3.82 kg/m2, 90.7±48.3 cm and 25.8±6.2 % respectively. The results also showed that 0.6% of them were underweight, 41.5% were normal, 44.8% were overweight and 13% were obese. The percentage of 34.8% firefighters with WC values of more than 90 cm means that they were at greater risk to have cardiovascular and diabetes disease. Body composition analysis showed that 75.5% of the subjects have high body fat level, 19.7% subjects were in healthy range but only 4.8% were considered as lean subjects. BMI was highly correlated with weight (r=0.917, p<0.01), WC (r=0.858, p<0.01) and body fat percentage (r=0.757, <0.01). Body fat percentage also showed to have a high correlation with BMI (r=0.757, p<0.01) and WC (r=0.693, p<0.01). Furthermore, overweight and obesity were found to be more prevalent among firefighters personnel of older age, married, less educated and have longer duration of services. It can be concluded that more than half of the firefighter personnel were either overweight or obese and 35% of them were at greater risk of having non-communicable diseases. This study provides useful information and serves as a source of

  13. Scaling of human body composition to stature: new insights into body mass index.

    Science.gov (United States)

    Heymsfield, Steven B; Gallagher, Dympna; Mayer, Laurel; Beetsch, Joel; Pietrobelli, Angelo

    2007-07-01

    Although Quetelet first reported in 1835 that adult weight scales to the square of stature, limited or no information is available on how anatomical body compartments, including adipose tissue (AT), scale to height. We examined the critical underlying assumptions of adiposity-body mass index (BMI) relations and extended these analyses to major anatomical compartments: skeletal muscle (SM), bone, residual mass, weight (AT+SM+bone), AT-free mass, and organs (liver, brain). This was a cross-sectional analysis of 2 body-composition databases: one including magnetic resonance imaging and dual-energy X-ray absorptiometry (DXA) estimates of evaluated components in adults (total n=411; organs=76) and the other a larger DXA database (n=1346) that included related estimates of fat, fat-free mass, and bone mineral mass. Weight, primary lean components (SM, residual mass, AT-free mass, and fat-free mass), and liver scaled to height with powers of approximately 2 (all P2 (2.31-2.48), and the fraction of weight as bone mineral mass was significantly (Pshort and tall subjects with equivalent BMIs have similar but not identical body composition, provide new insights into earlier BMI-related observations and thus establish a foundation for height-normalized indexes, and create an analytic framework for future studies.

  14. Scaling of human body composition to stature: new insights into body mass index 123

    Science.gov (United States)

    Heymsfield, Steven B; Gallagher, Dympna; Mayer, Laurel; Beetsch, Joel; Pietrobelli, Angelo

    2009-01-01

    Background Although Quetelet first reported in 1835 that adult weight scales to the square of stature, limited or no information is available on how anatomical body compartments, including adipose tissue (AT), scale to height. Objective We examined the critical underlying assumptions of adiposity–body mass index (BMI) relations and extended these analyses to major anatomical compartments: skeletal muscle (SM), bone, residual mass, weight (AT+SM+bone), AT-free mass, and organs (liver, brain). Design This was a cross-sectional analysis of 2 body-composition databases: one including magnetic resonance imaging and dual-energy X-ray absorptiometry (DXA) estimates of evaluated components in adults (total n = 411; organs = 76) and the other a larger DXA database (n = 1346) that included related estimates of fat, fat-free mass, and bone mineral mass. Results Weight, primary lean components (SM, residual mass, AT-free mass, and fat-free mass), and liver scaled to height with powers of ≈2 (all P 2 (2.31–2.48), and the fraction of weight as bone mineral mass was significantly (P short and tall subjects with equivalent BMIs have similar but not identical body composition, provide new insights into earlier BMI-related observations and thus establish a foundation for height-normalized indexes, and create an analytic framework for future studies. PMID:17616766

  15. Relationships between central arterial stiffness, lean body mass, and absolute and relative strength in young and older men and women.

    Science.gov (United States)

    Fahs, Christopher A; Thiebaud, Robert S; Rossow, Lindy M; Loenneke, Jeremy P; Bemben, Debra A; Bemben, Michael G

    2017-08-16

    Relationships between muscular strength and arterial stiffness as well as between muscle mass and arterial stiffness have been observed suggesting a link between the neuromuscular system and vascular health. However, the relationship between central arterial stiffness and absolute and relative strength along with muscle mass has not been investigated in both sexes across a broad age range. The purpose of this study was to examine the relationship between central arterial stiffness and absolute and relative strength as well as between central arterial stiffness and lean body mass (LBM) in men and women across a broad age range. LBM, central arterial stiffness and strength were measured on 36 men and 35 women between the ages of 18 and 75 years. Strength was measured on five machine resistance exercises and summed as one measure of overall strength (absolute strength). Relative strength was calculated as total strength divided by LBM (relative strength). Central arterial stiffness was inversely related to both absolute (r = -0·230; P = 0·029) and relative strength (r = -0·484; P LBM (r = 0·097; P = 0·213). The relationship between central arterial stiffness and relative strength was attenuated but still present when controlling for either age, per cent body fat, LBM or mean arterial pressure. These results suggest that, across a wide age range, the expression of relative muscular strength has a stronger relationship with central arterial stiffness compared to either LBM or absolute strength. This suggests that muscle function more than muscle mass may be coupled with vascular health. © 2017 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  16. Insights into relationships between body mass, composition and bone: findings in elite rugby players.

    Science.gov (United States)

    Hind, Karen; Gannon, Lisa; Brightmore, Amy; Beck, Belinda

    2015-01-01

    Recent reports indicate that bone strength is not proportional to body weight in obese populations. Elite rugby players have a similar body mass index (BMI) to obese individuals but differ markedly with low body fat, high lean mass, and frequent skeletal exposure to loading through weight-bearing exercise. The purpose of this study was to determine relationships between body weight, composition, and bone strength in male rugby players characterized by high BMI and high lean mass. Fifty-two elite male rugby players and 32 nonathletic, age-matched controls differing in BMI (30.2 ± 3.2 vs 24.1 ± 2.1 kg/m²; p = 0.02) received 1 total body and one total hip dual-energy X-ray absorptiometry scan. Hip structural analysis of the proximal femur was used to determine bone mineral density (BMD) and cross-sectional bone geometry. Multiple linear regression was computed to identify independent variables associated with total hip and femoral neck BMD and hip structural analysis-derived bone geometry parameters. Analysis of covariance was used to explore differences between groups. Further comparisons between groups were performed after normalizing parameters to body weight and to lean mass. There was a trend for a positive fat-bone relationship in rugby players, and a negative relationship in controls, although neither reached statistical significance. Correlations with lean mass were stronger for bone geometry (r(2): 0.408-0.520) than for BMD (r(2): 0.267-0.293). Relative to body weight, BMD was 6.7% lower in rugby players than controls (p Rugby players were heavier than controls, with greater lean mass and BMD (p rugby players (p rugby players was reduced in proportion to body weight and lean mass. However, their superior bone geometry suggests that overall bone strength may be adequate for loading demands. Fat-bone interactions in athletes engaged in high-impact sports require further exploration. Copyright © 2015. Published by Elsevier Inc.

  17. Unit-Sphere Multiaxial Stochastic-Strength Model Applied to Anisotropic and Composite Materials

    Science.gov (United States)

    Nemeth, Noel, N.

    2013-01-01

    Models that predict the failure probability of brittle materials under multiaxial loading have been developed by authors such as Batdorf, Evans, and Matsuo. These "unit-sphere" models assume that the strength-controlling flaws are randomly oriented, noninteracting planar microcracks of specified geometry but of variable size. This methodology has been extended to predict the multiaxial strength response of transversely isotropic brittle materials, including polymer matrix composites (PMCs), by considering (1) flaw-orientation anisotropy, whereby a preexisting microcrack has a higher likelihood of being oriented in one direction over another direction, and (2) critical strength, or K (sub Ic) orientation anisotropy, whereby the level of critical strength or fracture toughness for mode I crack propagation, K (sub Ic), changes with regard to the orientation of the microstructure. In this report, results from finite element analysis of a fiber-reinforced-matrix unit cell were used with the unit-sphere model to predict the biaxial strength response of a unidirectional PMC previously reported from the World-Wide Failure Exercise. Results for nuclear-grade graphite materials under biaxial loading are also shown for comparison. This effort was successful in predicting the multiaxial strength response for the chosen problems. Findings regarding stress-state interactions and failure modes also are provided.

  18. Comparison of shear bond strengths of conventional orthodontic composite and nano-ceramic restorative composite: an in vitro study.

    Science.gov (United States)

    Nagar, Namit; Vaz, Anna C

    2013-01-01

    To compare the shear bond strength of a nano-ceramic restorative composite Ceram-X Mono(TM♦), a restorative resin with the traditional orthodontic composite Transbond XT(TM†) and to evaluate the site of bond failure using Adhesive Remnant Index. Sixty extracted human premolars were divided into two groups of 30 each. Stainless steel brackets were bonded using Transbond XT(TM†) (Group I) and Ceram-X Mono(TM♦) (Group II) according to manufacturer's protocol. Shear bond strength was measured on Universal testing machine at crosshead speed of 1 mm/minute. Adhesive Remnant Index scores were assigned to debonded brackets of each group. Data was analyzed using unpaired 't' test and Chi square test. The mean shear bond strength of Group I (Transbond XT(TM†)) was 12.89 MPa ± 2.19 and that of Group II (Ceram-X Mono(TM)) was 7.29 MPa ± 1.76. Unpaired 't' test revealed statistically significant differences amongst the shear bond strength of the samples measured. Chi-square test revealed statistically insignificant differences amongst the ARI scores of the samples measured. Ceram-X Mono(TM♦) had a lesser mean shear bond strength when compared to Transbond XT(TM†) which was statistically significant difference. However, the mean shear bond of Ceram X Mono was within the clinically acceptable range for bonding. Ceram-X Mono(TM†) and Transbond XT(TM†) showed cohesive fracture of adhesive in 72.6% and 66.6% of the specimens, respectively.

  19. Comparison of shear bond strengths of conventional orthodontic composite and nano-ceramic restorative composite: An in vitro study

    Directory of Open Access Journals (Sweden)

    Namit Nagar

    2013-01-01

    Full Text Available Objectives: To compare the shear bond strength of a nano-ceramic restorative composite Ceram-X MonoTM♦, a restorative resin with the traditional orthodontic composite Transbond XTTM† and to evaluate the site of bond failure using Adhesive Remnant Index. Materials and Methods: Sixty extracted human premolars were divided into two groups of 30 each. Stainless steel brackets were bonded using Transbond XTTM† (Group I and Ceram-X MonoTM♦ (Group II according to manufacturer′s protocol. Shear bond strength was measured on Universal testing machine at crosshead speed of 1 mm/minute. Adhesive Remnant Index scores were assigned to debonded brackets of each group. Data was analyzed using unpaired ′t′ test and Chi square test. Results: The mean shear bond strength of Group I (Transbond XTTM† was 12.89 MPa ± 2.19 and that of Group II (Ceram-X MonoTM was 7.29 MPa ± 1.76. Unpaired ′t′ test revealed statistically significant differences amongst the shear bond strength of the samples measured. Chi-square test revealed statistically insignificant differences amongst the ARI scores of the samples measured. Conclusions: Ceram-X MonoTM♦ had a lesser mean shear bond strength when compared to Transbond XTTM† which was statistically significant difference. However, the mean shear bond of Ceram X Mono was within the clinically acceptable range for bonding. Ceram-X MonoTM† and Transbond XTTM† showed cohesive fracture of adhesive in 72.6% and 66.6% of the specimens, respectively.

  20. Effects of Arachidonic Acid Supplementation on Acute Anabolic Signaling and Chronic Functional Performance and Body Composition Adaptations.

    Directory of Open Access Journals (Sweden)

    Eduardo O De Souza

    Full Text Available The primary purpose of this investigation was to examine the effects of arachidonic acid (ARA supplementation on functional performance and body composition in trained males. In addition, we performed a secondary study looking at molecular responses of ARA supplementation following an acute exercise bout in rodents.Thirty strength-trained males (age: 20.4 ± 2.1 yrs were randomly divided into two groups: ARA or placebo (i.e. CTL. Then, both groups underwent an 8-week, 3-day per week, non-periodized training protocol. Quadriceps muscle thickness, whole-body composition scan (DEXA, muscle strength, and power were assessed at baseline and post-test. In the rodent model, male Wistar rats (~250 g, ~8 weeks old were pre-fed with either ARA or water (CTL for 8 days and were fed the final dose of ARA prior to being acutely strength trained via electrical stimulation on unilateral plantar flexions. A mixed muscle sample was removed from the exercised and non-exercised leg 3 hours post-exercise.Lean body mass (2.9%, p<0.0005, upper-body strength (8.7%, p<0.0001, and peak power (12.7%, p<0.0001 increased only in the ARA group. For the animal trial, GSK-β (Ser9 phosphorylation (p<0.001 independent of exercise and AMPK phosphorylation after exercise (p-AMPK less in ARA, p = 0.041 were different in ARA-fed versus CTL rats.Our findings suggest that ARA supplementation can positively augment strength-training induced adaptations in resistance-trained males. However, chronic studies at the molecular level are required to further elucidate how ARA combined with strength training affect muscle adaptation.

  1. Tensile strength of ramie yarn (spinning by machine)/HDPE thermoplastic matrix composites

    International Nuclear Information System (INIS)

    Banowati, Lies; Hadi, Bambang K.; Suratman, Rochim; Faza, Aulia

    2016-01-01

    Technological developments should be trooped to prevent a gap between technology and environmental sustainability, then it needs to be developed “Green technology”. In this research is making of green composites which use natural fiber ramie as reinforcement. Whereas the matrix used was HDPE (High Density Polyethylene) thermoplastic polymer which could be recycled and had a good formability and flexibility. The ramie yarns and fibers for unidirectional (0°) direction respectively were mixed with HDPE powder and processed using hot compression molding. The surface morphology was observed by SEM (Scanning Electrone Microscopy). Results showed that both tensile strength of the ramie fiber/HDPE composites increased in comparison with the ramie yarn (spinning by machine)/HDPE composites. However, the ramie yarn (spinning by machine)/HDPE composites have a good producibility for wider application. Analysis of the test results using the Weibull distribution as approaches to modeling the reliability of the specimens.

  2. Tensile strength of ramie yarn (spinning by machine)/HDPE thermoplastic matrix composites

    Energy Technology Data Exchange (ETDEWEB)

    Banowati, Lies, E-mail: liesbano@gmail.com; Hadi, Bambang K., E-mail: bkhadi@ae.itb.ac.id; Suratman, Rochim, E-mail: rochim@material.itb.ac.id; Faza, Aulia [Faculty of Mechanical and Aerospace Engineering, Bandung Institute of Technology, Indonesia Jl. Ganesha 10, Bandung (Indonesia)

    2016-03-29

    Technological developments should be trooped to prevent a gap between technology and environmental sustainability, then it needs to be developed “Green technology”. In this research is making of green composites which use natural fiber ramie as reinforcement. Whereas the matrix used was HDPE (High Density Polyethylene) thermoplastic polymer which could be recycled and had a good formability and flexibility. The ramie yarns and fibers for unidirectional (0°) direction respectively were mixed with HDPE powder and processed using hot compression molding. The surface morphology was observed by SEM (Scanning Electrone Microscopy). Results showed that both tensile strength of the ramie fiber/HDPE composites increased in comparison with the ramie yarn (spinning by machine)/HDPE composites. However, the ramie yarn (spinning by machine)/HDPE composites have a good producibility for wider application. Analysis of the test results using the Weibull distribution as approaches to modeling the reliability of the specimens.

  3. Viscoelastic behaviour and static fatigue strength of glass/epoxy composites. Influence of hydrothermal ageing

    International Nuclear Information System (INIS)

    Chateauminois, Antoine

    1991-01-01

    As ageing strength of composites appears to be one of the main criteria of their durability, this research thesis addresses the hydrothermal ageing of unidirectional glass/epoxy composites used for load-bearing structures. After having presented the used materials (epoxy matrix, reinforcement, composite elaboration), the author present the experimental techniques: viscoelastic analysis, three-point bend static fatigue test, coupled gravimetry and calorimetry, and thermogravimetry. In the next parts, the author reports the study of water sorption processes (bibliographical study, experimental study of water sorption kinetics, experimental study of interfacial diffusion within the composite), the study of plasticizing phenomena (methodology of study of plasticizing phenomena, study of the modifications of the linear viscoelastic behaviour in the glass transition region and at room temperature, relationship between plasticizing and fatigue mechanical properties by fracture studies), and the study of irreversible degradation and damage mechanisms

  4. Association between body composition and body mass index in young Japanese women.

    Science.gov (United States)

    Yamagishi, Hiroyuki; Kitano, Takao; Kuchiki, Tsutomu; Okazaki, Hideki; Shibata, Shigeo

    2002-06-01

    The National Nutrition Survey of Japan indicated a trend toward a decreasing body mass index (BMI; kg/m2) among young Japanese women. Current studies suggest that not-high BMI often does not correlate with not-high body fat percentage. Recently, the classification of BMI in adult Asians was proposed by the International Obesity Task Force. The addition of an "at risk of overweight" category, BMI as 23.0-24.9, was intended to prevent chronic diseases. We investigated the association between body fat percentage (BF%) and BMI to evaluate the screening performance of BMI focused on individual preventive medicine. The subjects consisted of 605 female college students. The subjects' ages (y), heights (cm), body weights (kg), BMIs, and BF percents with underwater weighing expressed as the means +/- SD were 19.6 +/- 0.5, 158.7 +/- 5.6, 53.8 +/- 7.2, 21.3 +/- 2.4, and 24.9 +/- 4.9, respectively. We defined high BF% as +/- 85th percentile of BF% (29.8%). High-BF% individuals are often not classified into BMI > or = 23.0 because their BMI readings are very broad (18.4-31.7). In comparison to the screening performances (specificity and sensitivity), BMI > or = 23.0 (85.3% and 52.1%, respectively), rather than BMI > or = 25.0 (96.7% and 29.8%, respectively), is recommended for the mass evaluation of fatness. For this reason, the BMI "at risk of overweight" category is characterized as the threshold of increasing the appearance ratio of high-BF% individuals. In conclusion, the BMI > or = 25.0 kg/m2 category is determined as high BF%, regardless of body composition measurement for mass evaluation as a result of quite high specificity. Even so, body composition measurement is necessitated by the individual evaluation of fatness focused on preventive medicine because BMI performed a poor representation of body composition, especially BMI < 25.0 kg/m2 individuals.

  5. Physical activity, body composition and metabolic syndrome in young adults.

    Directory of Open Access Journals (Sweden)

    Minna K Salonen

    Full Text Available Low physical activity (PA is a major risk factor for cardiovascular and metabolic disorders in all age groups. We measured intensity and volume of PA and examined the associations between PA and the metabolic syndrome (MS, its components and body composition among young Finnish adults.The study comprises 991 men and women born 1985-86, who participated in a clinical study during the years 2009-11 which included assessments of metabolism, body composition and PA. Objectively measured (SenseWear Armband five-day PA data was available from 737 participants and was expressed in metabolic equivalents of task (MET.The prevalence of MS ranged between 8-10%. Higher total mean volume (MET-hours or intensity (MET were negatively associated with the risk of MS and separate components of MS, while the time spent at sedentary level of PA was positively associated with MS.MS was prevalent in approximately every tenth of the young adults at the age of 24 years. Higher total mean intensity and volume rates as well as longer duration spent at moderate and vigorous PA level had a beneficial impact on the risk of MS. Longer time spent at the sedentary level of PA increased the risk of MS.

  6. Nutritional assessment by isotope dilution analysis of body composition

    International Nuclear Information System (INIS)

    Szeluga, D.J.; Stuart, R.K.; Utermohlen, V.; Santos, G.W.

    1984-01-01

    The three components of body mass, body cell mass (BCM), extracellular fluid (ECF), and fat + extracellular solids (ECS: bone, tendon, etc) can be quantified using established isotope dilution techniques. With these techniques, total body water (TBW) and ECF are measured using 3H 2 O and 82 Bromine, respectively, as tracers. BCM is calculated from intracellular fluid (ICF) where ICF . TBW - ECF. Fat + ECS is estimated as: body weight - (BCM + ECF). TBW and ECF can be determined by either of two calculation methods, one requiring several timed plasma samples (extrapolation method) and one requiring a single plasma sample and a 4-h urine collection (urine-corrected method). The comparability of the two calculation methods was evaluated in 20 studies in 12 bone marrow transplant recipients. We found that for determination of TBW and ECF there was a very strong linear relationship (r2 greater than 0.98) between the calculation methods. Further comparisons (by t test, 2-sided) indicated that for the determination of ECF, the methods were not significantly (p greater than 0.90) different; however, TBW determined by the urine-corrected method was slightly (0.1 to 6%), but significantly (p less than 0.01) greater than that determined by the extrapolation method. Therefore, relative to the extrapolation method, the urine-corrected method ''over-estimates'' BCM and ''under-estimates'' fat + ECS since determination of these compartment sizes depends on measurement of TBW. We currently use serial isotope dilution studies to monitor the body composition changes of patients receiving therapeutic nutritional support

  7. Effects of different modes of exercise training on body composition and risk factors for cardiovascular disease in middle-aged men

    Directory of Open Access Journals (Sweden)

    Hamid Reza Mohammadi

    2018-01-01

    Full Text Available Background: Previous studies have indicated that exercise training improves body composition and cardiovascular disease risk factors. The aim of the present study was to investigate the effect of 12 weeks of aerobic, strength and combined training on body composition, intercellular adhesion molecule-1 (ICAM-1, vascular cell adhesion molecule-1 (VCAM-1, and C-reactive protein (CRP in sedentary middle-aged men. Methods: Forty-seven male aged 40–60 years voluntarily participated in this study and were divided in four groups: aerobic (n = 12, strength (n = 12, combined (n = 11, and control (n = 12 groups randomly. Body composition, ICAM-1, VCAM-1, and CRP were measured before and after 12 weeks. Data were analyzed using paired t-test and analysis of variance statistical methods. Results: There were significant differences in body weight between aerobic and strength training (P = 0.004 and aerobic and control groups (P = 0.018, body mass index between combined and strength training (P = 0.004 and combined and control groups (P = 0.001, fat percentage between aerobic training and control group (P = 0.017 and combined training and control groups (P = 0.004, and finally, fat-free mass between aerobic and strength training (P = 0.024, aerobic and combined training (P = 0.0001, strength and control groups (P = 0.035, and combined and control groups (P = 0.0001. Conclusions: The results indicated that 12-week workout, 20–60 min/session, 3 days a week of moderate intensity exercise improved body composition, ICAM-1, VCAM-1, and CRP compared to those who did not participate in any training. However, all three types of exercises had small benefits on body composition, ICAM-1, VCAM-1, and CRP in sedentary middle-aged men, and the importance of combined training required further investigations.

  8. High-Strength Composite Fabric Tested at Structural Benchmark Test Facility

    Science.gov (United States)

    Krause, David L.

    2002-01-01

    Large sheets of ultrahigh strength fabric were put to the test at NASA Glenn Research Center's Structural Benchmark Test Facility. The material was stretched like a snare drum head until the last ounce of strength was reached, when it burst with a cacophonous release of tension. Along the way, the 3-ft square samples were also pulled, warped, tweaked, pinched, and yanked to predict the material's physical reactions to the many loads that it will experience during its proposed use. The material tested was a unique multi-ply composite fabric, reinforced with fibers that had a tensile strength eight times that of common carbon steel. The fiber plies were oriented at 0 and 90 to provide great membrane stiffness, as well as oriented at 45 to provide an unusually high resistance to shear distortion. The fabric's heritage is in astronaut space suits and other NASA programs.

  9. Application of Composite Structures in Bridge Engineering. Problems of Construction Process and Strength Analysis

    Science.gov (United States)

    Flaga, Kazimierz; Furtak, Kazimierz

    2015-03-01

    Steel-concrete composite structures have been used in bridge engineering from decades. This is due to rational utilisation of the strength properties of the two materials. At the same time, the reinforced concrete (or prestressed) deck slab is more favourable than the orthotropic steel plate used in steel bridges (higher mass, better vibration damping, longer life). The most commonly found in practice are composite girder bridges, particularly in highway bridges of small and medium spans, but the spans may reach over 200 m. In larger spans steel truss girders are applied. Bridge composite structures are also employed in cable-stayed bridge decks of the main girder spans of the order of 600, 800 m. The aim of the article is to present the cionstruction process and strength analysis problems concerning of this type of structures. Much attention is paid to the design and calculation of the shear connectors characteristic for the discussed objects. The authors focused mainly on the issues of single composite structures. The effect of assembly states on the stresses and strains in composite members are highlighted. A separate part of problems is devoted to the influence of rheological factors, i.e. concrete shrinkage and creep, as well as thermal factors on the stresses and strains and redistribution of internal forces.

  10. Experimental Tensile Strength Analysis of Woven-Glass/Epoxy Composite Plates with Central Circular Hole

    Science.gov (United States)

    Hadi, Bambang K.; Rofa, Bima K.

    2018-04-01

    The use of composite materials in aerospace engineering, as well as in maritime structure has increased significantly during the recent years. The extensive use of composite materials in industrial applications should make composite structural engineers and scientists more aware of the advantage and disadvantage of this material and provide them with necessary data and certification process. One of the problems in composite structures is the existence of hole. Hole can not be avoided in actual structures, since it may be the necessity of providing access for maintenance or due to impact damage. The presence of hole will weaken the structures. Therefore, in this paper, the effect of hole on the strength of glass-woven/epoxy composite will be discussed. Extensive tests have been carried out to study the effect of hole-diameter on the tensile strengths of these specimens. The results showed that the bigger the hole-diameter compared to the width of the specimens has weakened the structures further, as expected. Further study should be carried in the future to model it with the finite element and theoretical analysis precisely.

  11. Strength and fatigue life evaluation of composite laminate with embedded sensors

    Science.gov (United States)

    Rathod, Vivek T.; Hiremath, S. R.; Roy Mahapatra, D.

    2014-04-01

    Prognosis regarding durability of composite structures using various Structural Health Monitoring (SHM) techniques is an important and challenging topic of research. Ultrasonic SHM systems with embedded transducers have potential application here due to their instant monitoring capability, compact packaging potential toward unobtrusiveness and noninvasiveness as compared to non-contact ultrasonic and eddy current techniques which require disassembly of the structure. However, embedded sensors pose a risk to the structure by acting as a flaw thereby reducing life. The present paper focuses on the determination of strength and fatigue life of the composite laminate with embedded film sensors like CNT nanocomposite, PVDF thin films and piezoceramic films. First, the techniques of embedding these sensors in composite laminates is described followed by the determination of static strength and fatigue life at coupon level testing in Universal Testing Machine (UTM). Failure mechanisms of the composite laminate with embedded sensors are studied for static and dynamic loading cases. The coupons are monitored for loading and failure using the embedded sensors. A comparison of the performance of these three types of embedded sensors is made to study their suitability in various applications. These three types of embedded sensors cover a wide variety of applications, and prove to be viable in embedded sensor based SHM of composite structures.

  12. Microtensile bond strength of silorane-based composite specific adhesive system using different bonding strategies

    OpenAIRE

    Bastos, Laura Alves; Sousa, Ana Beatriz Silva; Drubi-Filho, Brahim; Panzeri Pires-de-Souza, Fernanda de Carvalho; Garcia, Lucas da Fonseca Roberti

    2014-01-01

    Objectives The aim of this study was to evaluate the effect of pre-etching on the bond strength of silorane-based composite specific adhesive system to dentin. Materials and Methods Thirty human molars were randomly divided into 5 groups according to the different bonding strategies. For teeth restored with silorane-based composite (Filtek Silorane, 3M ESPE), the specific self-etching adhesive system (Adhesive System P90, 3M ESPE) was used with and without pre-etching (Pre-etching/S...

  13. High strength Ni based composite reinforced by solid solution W(Al) obtained by powder metallurgy

    International Nuclear Information System (INIS)

    Zhao Bo; Zhu Changjun; Ma Xianfeng; Zhao Wei; Tang Huaguo; Cai Shuguang; Qiao Zhuhui

    2007-01-01

    The solid-solution-particle reinforced W(Al)-Ni composites were successfully fabricated by using mechanical alloying (MA) and hot-pressing (HP) technique when the content of Ni is between 45 wt% and 55 wt%. Besides, samples of various original component ratio of Al 50 W 50 to Ni have been fabricated, and the corresponding microcomponents and mechanical properties such as microhardness, ultimate tensile strength and elongation were characterized and discussed. The optimum ultimate tensile strength under the experiment conditions is 1868 MPa with elongation of 10.21% and hardness of 6.62 GPa. X-ray diffraction (XRD), FE-SEM and energy dispersive analysis of X-rays (EDS) were given to analysis the components and morphology of the composite bulk specimens

  14. Development of Compressive Failure Strength for Composite Laminate Using Regression Analysis Method

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myoung Keon [Agency for Defense Development, Daejeon (Korea, Republic of); Lee, Jeong Won; Yoon, Dong Hyun; Kim, Jae Hoon [Chungnam Nat’l Univ., Daejeon (Korea, Republic of)

    2016-10-15

    This paper provides the compressive failure strength value of composite laminate developed by using regression analysis method. Composite material in this document is a Carbon/Epoxy unidirection(UD) tape prepreg(Cycom G40-800/5276-1) cured at 350°F(177°C). The operating temperature is –60°F~+200°F(-55°C - +95°C). A total of 56 compression tests were conducted on specimens from eight (8) distinct laminates that were laid up by standard angle layers (0°, +45°, –45° and 90°). The ASTM-D-6484 standard was used for test method. The regression analysis was performed with the response variable being the laminate ultimate fracture strength and the regressor variables being two ply orientations (0° and ±45°)

  15. Bioinspired, Graphene/Al2O3 Doubly Reinforced Aluminum Composites with High Strength and Toughness.

    Science.gov (United States)

    Zhang, Yunya; Li, Xiaodong

    2017-11-08

    Nacre, commonly referred to as nature's armor, has served as a blueprint for engineering stronger and tougher bioinspired materials. Nature organizes a brick-and-mortar-like architecture in nacre, with hard bricks of aragonite sandwiched with soft biopolymer layers. However, cloning nacre's entire reinforcing mechanisms in engineered materials remains a challenge. In this study, we employed hybrid graphene/Al 2 O 3 platelets with surface nanointerlocks as hard bricks for primary load bearer and mechanical interlocking, along with aluminum laminates as soft mortar for load distribution and energy dissipation, to replicate nacre's architecture and reinforcing effects in aluminum composites. Compared with aluminum, the bioinspired, graphene/Al 2 O 3 doubly reinforced aluminum composite demonstrated an exceptional, joint improvement in hardness (210%), strength (223%), stiffness (78%), and toughness (30%), which are even superior over nacre. This design strategy and model material system should guide the synthesis of bioinspired materials to achieve exceptionally high strength and toughness.

  16. Development of Compressive Failure Strength for Composite Laminate Using Regression Analysis Method

    International Nuclear Information System (INIS)

    Lee, Myoung Keon; Lee, Jeong Won; Yoon, Dong Hyun; Kim, Jae Hoon

    2016-01-01

    This paper provides the compressive failure strength value of composite laminate developed by using regression analysis method. Composite material in this document is a Carbon/Epoxy unidirection(UD) tape prepreg(Cycom G40-800/5276-1) cured at 350°F(177°C). The operating temperature is –60°F~+200°F(-55°C - +95°C). A total of 56 compression tests were conducted on specimens from eight (8) distinct laminates that were laid up by standard angle layers (0°, +45°, –45° and 90°). The ASTM-D-6484 standard was used for test method. The regression analysis was performed with the response variable being the laminate ultimate fracture strength and the regressor variables being two ply orientations (0° and ±45°)

  17. Long-term Bond Strength between Layering Indirect Composite Material and Zirconia Coated with Silicabased Ceramics.

    Science.gov (United States)

    Fushiki, Ryosuke; Komine, Futoshi; Honda, Junichi; Kamio, Shingo; Blatz, Markus B; Matsumura, Hideo

    2015-06-01

    This study evaluated the long-term shear bond strength between an indirect composite material and a zirconia framework coated with silica-based ceramics, taking the effect of different primers into account. A total of 165 airborne-particle abraded zirconia disks were subjected to one of three pretreatments: no pretreatment (ZR-AB), airborne-particle abrasion of zirconia coated with feldspathic porcelain (ZR-PO-AB), and 9.5% hydrofluoric acid etching of zirconia coated with feldspathic porcelain (ZR-PO-HF). An indirect composite material (Estenia C&B) was then bonded to the zirconia disks after they were treated with one of the following primers: Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB + Activator), Estenia Opaque Primer (EOP), Porcelain Liner M Liquid B (PLB), or no priming (CON, control group). Shear bond strength was tested after 100,000 thermocycles, and the data were analyzed using the Steel-Dwass U-test (α = 0.05). For ZR-PO-AB and ZR-PO-HF specimens, bond strength was highest in the CPB+Activator group (25.8 MPa and 22.4 MPa, respectively). Bond strengths were significantly lower for ZR-AB specimens in the CON and PLB groups and for ZR-PO-AB specimens in the CON, CPB, and EOP groups. Combined application of a hydrophobic phosphate monomer (MDP) and silane coupling agent enhanced the long-term bond strength of indirect composite material to a zirconia coated with silica-based ceramics.

  18. PENGARUH FRAKSI VOLUME PENGUAT TERHADAP KEKUATAN LENTUR GREEN COMPOSITE UNTUK APLIKASI PADA BODI KENDARAAN

    Directory of Open Access Journals (Sweden)

    Mastariyanto Perdana

    2016-07-01

    Full Text Available Composites are one of material be used in engineering field. This is due the composites has light weight and relatively strong properties. The synthesis fiber-based composites reduces to obtain environmental friendly properties. This research use hybrid fiber which consist of calcium carbonate (CaCO3 powder and bagasse fiber. Matrix used is resin polyester. Variation of volume fraction between bagasse and calcium carbonate powder are 10:20, 15:15 and 20:10 respectively. Volume fraction of hybrid fiber and polyester is 30:70. This study aims to determine mechanical properties of hybrid composites for each variation of volume fraction. Test results showed. Bending strength of bagasse-based hybrid composites and powder of calcium carbonate with a variation of volume fraction of 10%: 20%, 15%: 15% and 20%: 10% are 53.77 MPa, 54.90 MPa and 59.76 MPa. Hybrid composites with volume fraction 20% bagasse and 10% calcium carbonate powder has highest of bending strength. Green composite based bagasse and calcium carbonate powder can use on application of vehicle body.Komposit merupakan salah satu material yang banyak digunakan pada bidang keteknikan. Ini dikarenakan komposit memiliki sifat ringan dan relatif kuat. Untuk mendapakatkan sifat yang ramah lingkungan, penggunaan komposit yang berbasis serat sintesis dikurangi penggunaannya. Penelitian ini menggunakan serat hibrid yaitu penggabungan antara serbuk kalsium karbonat (CaCO3 dan serat ampas tebu (bagasse. Matrix yang digunakan adalah resin polyester.Variasi fraksi volume antara bagasse dan serbuk kalsium karbonat masing-masing adalah 10:20, 15:15 dan 20:10. Fraksi volume antara serat hibrid dan resin polyester adalah 30:70. Penelitian ini bertujuan untuk mengetahui sifat mekanik dari komposit hibrid berbasis bagasse dan serbuk kalsium karbonat untuk masing-masing variasi fraksi volume. Hasil pengujian menunjukkan bahwakekuatan bending tertinggi komposit hibrid berbasis bagasse dan serbuk kalsium

  19. Gender differences in body composition, physical activity, eating behavior and body image among normal weight adolescents--an evolutionary approach.

    Science.gov (United States)

    Kirchengast, Sylvia; Marosi, Andrea

    2008-12-01

    Body composition but also physical activity patterns underlie gender typical differences throughout human life. In the present study the body composition of 354 girls and 280 boys ageing between 11 and 18 years originating from Eastern Austria were analyzed using bioelectrical impedance method. Normal weight according to body mass index categories was a strict inclusion criterion. Information regarding physical activity during school and leisure time, daily nutritional habits, subjective body satisfaction and weight control practices were collected by means of a structured and standardized questionnaire. Results of the analyses reveal that--as to be expected--adolescent boys and girls differed significantly in body composition, but also in physical activity patterns. Even normal weight girls exhibited a significantly higher amount of absolute and relative fat mass, whereas normal weight boys showed a significantly higher amount of fat free body mass. Furthermore male adolescents were significantly more physically active than their female counterparts. According to the results of multiple regression analyses physical activity patterns had beside sex an independent influence on body composition parameters during adolescence. In contrast, girls and boys showed only minor differences in nutritional habits and weight control practices. Nutritional habits, body satisfaction and weight control practices were not significantly related to body composition parameters. The observed gender differences in body composition as well as in physical activity patterns are interpreted in an evolutionary sense.

  20. Does a 3-month multidisciplinary intervention improve pain, body composition and physical fitness in women with fibromyalgia?

    Science.gov (United States)

    Carbonell-Baeza, Ana; Aparicio, Virginia A; Ortega, Francisco B; Cuevas, Ana M; Alvarez, Inmaculada C; Ruiz, Jonatan R; Delgado-Fernandez, Manuel

    2011-12-01

    To determine the effects of a 3-month multidisciplinary intervention on pain (primary outcome), body composition and physical fitness (secondary outcomes) in women with fibromyalgia (FM). 75 women with FM were allocated to a low-moderate intensity 3-month (three times/week) multidisciplinary (pool, land-based and psychological sessions) programme (n=33) or to a usual care group (n=32). The outcome variables were pain threshold, body composition (body mass index and estimated body fat percentage) and physical fitness (30 s chair stand, handgrip strength, chair sit and reach, back scratch, blind flamingo, 8 feet up and go and 6 min walk test). The authors observed a significant interaction effect (group*time) for the left (L) and right (R) side of the anterior cervical (pbody composition variables. A 3-month multidisciplinary intervention three times/week had a positive effect on pain threshold in several tender points in women with FM. Though no overall improvements were observed in physical fitness or body composition, the intervention had positive effects on lower-body flexibility.

  1. Whole body BMC in pediatric Crohn disease: independent effects of altered growth, maturation, and body composition.

    Science.gov (United States)

    Burnham, Jon M; Shults, Justine; Semeao, Edisio; Foster, Bethany; Zemel, Babette S; Stallings, Virginia A; Leonard, Mary B

    2004-12-01

    Whole body BMC was assessed in 104 children and young adults with CD and 233 healthy controls. CD was associated with significant deficits in BMC and lean mass, relative to height. Adjustment for lean mass eliminated the bone deficit in CD. Steroid exposure was associated with short stature but not bone deficits relative to height. Children with Crohn disease (CD) have multiple risk factors for impaired bone accrual. The confounding effects of poor growth and delayed maturation limit the interpretation of prior studies of bone health in CD. The objective of this study was to assess BMC relative to growth, body composition, and maturation in CD compared with controls. Whole body BMC and lean mass were assessed by DXA in 104 CD subjects and 233 healthy controls, 4-26 years of age. Multivariable linear regression models were developed to sequentially adjust for differences in skeletal size, pubertal maturation, and muscle mass. BMC-for-height z scores were derived to determine CD-specific covariates associated with bone deficits. Subjects with CD had significantly lower height z score, body mass index z score, and lean mass relative to height compared with controls (all p BMC in CD relative to controls was significantly reduced in males (0.86; 95% CI, 0.83, 0.94) and females (0.91; 95% CI, 0.85, 0.98) with CD. Adjustment for pubertal maturation did not alter the estimate; however, addition of lean mass to the model eliminated the bone deficit. Steroid exposure was associated with short stature but not bone deficits. This study shows the importance of considering differences in body size and composition when interpreting DXA data in children with chronic inflammatory conditions and shows an association between deficits in muscle mass and bone in pediatric CD.

  2. Manufacture of high-strength composite materials from prepregs prepared by radiation processing

    International Nuclear Information System (INIS)

    Laricheva, V.P.; Korotkij, A.F.

    2008-01-01

    Scientific principles of the manufacture of high-strength heat-resistant polymer composite materials with the successive ionizing-radiation and heat treatment (via the step of long-lived prepregs) were developed. Methods for the selection of components for the preparation of long-lived prepregs, as well as for the determination of the optimal curing conditions, were proposed. The mechanical properties of the materials were studied [ru

  3. Fabrication of high strength PVA/SWCNT composite fibers by gel spinning

    OpenAIRE

    Xu, Xuezhu; Uddin, Ahmed Jalal; Aoki, Kenta; Gotoh, Yasuo; Saito, Takeshi; Yumura, Motoo

    2010-01-01

    High-strength composite fibers were prepared from polyvinyl alcohol (PVA) (Degree of polymerization: 1500) reinforced by single-walled carbon nanotubes (SWCNTs) containing few defects. The SWCNTs were dispersed in a 10 wt.% PVA/dimethylsulfoxide solution using a mechanical homogenizer that reduced the size of SWCNT aggregations to smaller bundles. The macroscopically homogeneous dispersion was extruded into cold methanol to form fibers by gel spinning followed by a hot-drawing. The tensile st...

  4. The influence of maternal body composition on birth weight.

    LENUS (Irish Health Repository)

    Farah, Nadine

    2012-02-01

    OBJECTIVE: To identify the maternal body composition parameters that independently influence birth weight. STUDY DESIGN: A longitudinal prospective observational study in a large university teaching hospital. One hundred and eighty-four non-diabetic caucasian women with a singleton pregnancy were studied. In early pregnancy maternal weight and height were measured digitally in a standardised way and the body mass index (BMI) was calculated. At 28 and 37 weeks\\' gestation maternal body composition was assessed using segmental multifrequency bioelectrical impedance analysis. At delivery the baby was weighed and the clinical details were recorded. RESULTS: Of the women studied, 29.2% were overweight and 34.8% were obese. Birth weight did not correlate with maternal weight or BMI in early pregnancy. Birth weight correlated with gestational weight gain (GWG) before the third trimester (r=0.163, p=0.027), but not with GWG in the third trimester. Birth weight correlated with maternal fat-free mass, and not fat mass at 28 and 37 weeks gestation. Birth weight did not correlate with increases in maternal fat and fat-free masses between 28 and 37 weeks. CONCLUSIONS: Contrary to previous reports, we found that early pregnancy maternal BMI in a non-diabetic population does not influence birth weight. Interestingly, it was the GWG before the third trimester and not the GWG in the third trimester that influenced birth weight. Our findings have implications for the design of future intervention studies aimed at optimising gestational weight gain and birth weight. CONDENSATION: Maternal fat-free mass and gestational weight gain both influence birth weight.

  5. Correlation between Body Composition and Walking Capacity in Severe Obesity.

    Science.gov (United States)

    Correia de Faria Santarém, G; de Cleva, R; Santo, Marco Aurélio; Bernhard, Aline Biaseto; Gadducci, Alexandre Vieira; Greve, Julia Maria D'Andrea; Silva, Paulo Roberto Santos

    2015-01-01

    Obesity is associated with mobility reduction due to mechanical factors and excessive body fat. The six-minute walk test (6MWT) has been used to assess functional capacity in severe obesity. To determine the association of BMI, total and segmental body composition with distance walked (6MWD) during the six-minute walk test (6MWT) according to gender and obesity grade. University of São Paulo Medical School, Brazil; Public Practice. Functional capacity was assessed by 6MWD and body composition (%) by bioelectrical impedance analysis in 90 patients. The mean 6MWD was 514.9 ± 50.3 m for both genders. The male group (M: 545.2 ± 46.9 m) showed a 6MWD higher (p = 0.002) than the female group (F: 505.6 ± 47.9 m). The morbid obese group (MO: 524.7 ± 44.0 m) also showed a 6MWD higher (p = 0.014) than the super obese group (SO: 494.2 ± 57.0 m). There was a positive relationship between 6MWD and fat free mass (FFM), FFM of upper limps (FFM_UL), trunk (FFM_TR) and lower limbs (FFM_LL). Female group presented a positive relationship between 6MWD and FFM, FFM_UL and FFM_LL and male group presented a positive relationship between 6MWD and FFM_TR. In morbid obese group there was a positive relationship between 6MWD with FFM, FFM_UL, FFM_TR and FFM_LL. The super obese group presented a positive relationship between 6MWD with FFM, FFM_TR and FFM_LL. Total and segmental FFM is associated with a better walking capacity than BMI.

  6. Can Whitening Strips interfere with the Bond Strength of Composite Resins?

    Science.gov (United States)

    Firoozmand, Leily Macedo; Reis, Washington Luís Machado dos; Vieira, Mercêdes Aroucha; Nunes, Adriana Gomes; Tavarez, Rudys Rodolfo de Jesus; Tonetto, Mateus Rodrigues; Bramante, Fausto Silva; Bhandi, Shilpa H; Roma, Regina Vieira de Oliveira; Bandeca, Matheus Coelho

    2015-04-01

    The aim of this study was to investigate in vitro the bond strength of composite resins on enamel previously treated with whitening strips. A total of 48 bovine incisors were allocated to four experimental groups (n = 12 each): G1 (WSC)- treated with 9.5% hydrogen peroxide whitening strips (3D White Whitestrips® Advanced Vivid/CREST); G2 (WSO)-treated with 10% hydrogen peroxide whitening strips (3D WhiteTM/Oral B); G3 (WG)-treated with 7.5% hydrogen peroxide gel with fluorine, calcium and potassium nitrate (White Class®/FGM); and G4 (C)-control not subjected to bleaching treatment. The specimens were subjected to bleaching over 2 weeks following the manufacturers' instructions. Following the elaboration of the composite resin test specimens, the samples were stored in artificial saliva and subsequently subjected to the micro-shear test using the universal testing machine (EMIC®). The bond strength values were analyzed by one-way ANOVA and Tukey's statistical test (5%). Significant differences were observed among the investigated groups (p enamel-resin interface. The bond strength decreased following 14 days of treatment with bleaching strips, whereas the whitening gel with 7.5% hydrogen peroxide, calcium and fluorine increased the bond strength.

  7. Body composition and pulmonary function in Cystic Fibrosis

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    Saba eSheikh

    2014-04-01

    Full Text Available Background: Lower body mass index (BMI is associated with worse pulmonary function in cystic fibrosis (CF. Hypothesis: Lean body mass (LBM is more strongly associated with pulmonary function than BMI is.Methods: Anthropometrics, body composition by dual x-ray absorptiometry, and pulmonary function were determined in pancreatic insufficient CF (PI-CF youth. Sex and age-adjusted Z-scores (BMI-Z, LBMI-Z, FMI-Z were generated for CF and controls. 1 Associations of BMI-Z with LBMI-Z and FMI-Z and 2 age-adjusted associations of BMI-Z, LBMI-Z, and FMI-Z with FEV1%-predicted were tested. Results: 208 PI-CF subjects had lower BMI-Z, LBMI-Z, FMI-Z compared to 390 controls. BMI-Z was associated with lower LBMI-Z (pConclusions: In PI-CF youth, deficits in LBM were apparent. At lower BMI percentiles, BMI may not accurately depict LBM in PI-CF. In under-nourished PI-CF youth this preservation of FM in preference to LBM is relevant since LBMI-Z, but not FMI-Z, is positively associated with FEV1%-predicted. LBMI is more strongly associated with lung function compared to BMI, especially in the undernourished child and adolescent with PI-CF.

  8. Body Composition and Somatotype in Adolescent Competion Swimmers

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    José Miguel Martínez-Sanz

    2014-05-01

    Full Text Available Introduction: The swimmer is a high level athlete, with long limbs, and whose musculoskeletal components are important in sporting success. However, the fat component is paradoxical because of its relationship with the buoyancy and displacement of the body in the water. The aim of this study is to describe the anthropometric profile of adolescent competition swimmers.Material and methods: A total of 17 adolescent swimmers were evaluated, 10 boys (13.2 ±1.32 years and 7 girls (15±1.83 years. A qualified anthropometrist took anthropometric measures according to the protocol of the Society for the Advancement of Kinanthropometry (ISAK, with approved materials according to the methodology of Marfell-Jones et al, 2003. Body composition was calculated according to the consensus of Kinanthropometry and somatotype with Heath-Carter´s method.Results: Of all the variables studied (weight, height, folds, circumferences, diameters and lengths, significant differences were found (P<.05 between the sexes in height, arm span, skinfolds (triceps, subscapular, crestailiaca, ileo-spinal, abdominal, thigh, leg, sum of skinfolds, biacromial-bi-iliac index, bone body mass, muscle and fat, ectomorphy, and endomorphy.Conclusions: There are significant anthropometric differences between genders in adolescent swimmers (P<.05. Such differences, resulting in the development of both sexes, might be highly related to athletic performance of young athletes.

  9. Compressive strength and magnetic properties of calcium silicate-zirconia-iron (III) oxide composite cements

    Science.gov (United States)

    Ridzwan, Hendrie Johann Muhamad; Shamsudin, Roslinda; Ismail, Hamisah; Yusof, Mohd Reusmaazran; Hamid, Muhammad Azmi Abdul; Awang, Rozidawati Binti

    2018-04-01

    In this study, ZrO2 microparticles and γ-Fe2O3 nanoparticles have been added into calcium silicate based cements. The purpose of this experiment was to investigate the compressive strength and magnetic properties of the prepared composite cement. Calcium silicate (CAS) powder was prepared by hydrothermal method. SiO2 and CaO obtained from rice husk ash and limestone respectively were autoclaved at 135 °C for 8 h and sintered at 950°C to obtain CAS powder. SiO2:CaO ratio was set at 45:55. CAS/ZrO2 sample were prepared with varying ZrO2 microparticles concentrations by 0-40 wt. %. Compressive strength value of CAS/ZrO2 cements range from 1.44 to 2.44 MPa. CAS/ZrO2/γ-Fe2O3 sample with 40 wt. % ZrO2 were prepared with varying γ-Fe2O3 nanoparticles concentrations (1-5 wt. %). The additions of γ-Fe2O3 nanoparticles showed up to twofold increase in the compressive strength of the cement. X-Ray diffraction (XRD) results confirm the formation of mixed phases in the produced composite cements. Vibrating sample magnetometer (VSM) analysis revealed that the ferromagnetic behaviour has been observed in CAS/ZrO2/γ-Fe2O3 composite cements.

  10. Strength of normal sections of NPP composite monolithic constructions with ribbed reinforced panels

    International Nuclear Information System (INIS)

    Klyashitskij, V.I.; Kirillov, A.P.

    1980-01-01

    Strength characteristics and recommendations on designing composite-monolytic structures of NPP with ribbed reinforced panels are considered. Ribbed reinforced panel consists of a system of cross ribs joined with a comparatively thin (25 mm thick) plate. The investigations were carried on using models representing columns symmetrically reinforced with reinforced panels with a low percent of reinforcing. The monolithic structures consisting of ribbed reinforced panels and cast concrete for making monoliths as well as monolithic having analogous strength characteristics of extended and compressed zones have similar strengths. It is shown that calculation of supporting power of composite-monolithic structures is performed according to techniques developed for monolithic structures. Necessity of structural transverse fittings no longer arises in case of corresponding calculational substitution of stability of compressed parts of fittings. Supporting power of a structure decreases not more than by 10% in the presence of cracks in the reinforced panels of the compressed zone. Application of composite-monolithic structures during the construction of the Kursk, Smolensk and Chernobylskaya NPPs permitted to decrease labour content and reduce periods of accomplishment of these works which saves over 6 million roubles

  11. Effect of elevated temperature on the tensile strength of Napier/glass-epoxy hybrid reinforced composites

    Science.gov (United States)

    Ridzuan, M. J. M.; Majid, M. S. Abdul; Afendi, M.; Firdaus, A. Z. Ahmad; Azduwin, K.

    2017-11-01

    The effects of elevated temperature on the tensile strength of Napier/glass-epoxy hybrid reinforced composites and its morphology of fractured surfaces are discussed. Napier/glass-epoxy hybrid reinforced composites were fabricated by using vacuum infusion method by arranging Napier fibres in between sheets of woven glass fibres. Napier and glass fibres were laminated with estimated volume ratios were 24 and 6 vol. %, respectively. The epoxy resin was used as matrix estimated to 70 vol. %. Specimens were tested to failure under tension at a cross-head speed of 1 mm/min using Universal Testing Machine (Instron) with a load cell 100 kN at four different temperatures of RT, 40°C, 60°C and 80°C. The morphology of fractured surface of hybrid composites was investigated by field emission scanning electron microscopy. The result shows reduction in tensile strength at elevated temperatures. The increase in the temperature activates the process of diffusion, and generates critical stresses which cause the damage at first-ply or at the centre of the hybrid plate, as a result lower the tensile strength. The observation of FESEM images indicates that the fracture mode is of evolution of localized damage, from fibre/matrix debonding, matric cracking, delamination and fibre breakage.

  12. Repair Bond Strength of Aged Resin Composite after Different Surface and Bonding Treatments

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    Michael Wendler

    2016-07-01

    Full Text Available The aim of this study was to compare the effect of different mechanical surface treatments and chemical bonding protocols on the tensile bond strength (TBS of aged composite. Bar specimens were produced using a nanohybrid resin composite and aged in distilled water for 30 days. Different surface treatments (diamond bur, phosphoric acid, silane, and sandblasting with Al2O3 or CoJet Sand, as well as bonding protocols (Primer/Adhesive were used prior to application of the repair composite. TBS of the specimens was measured and the results were analyzed using analysis of variance (ANOVA and the Student–Newman–Keuls test (α = 0.05. Mechanically treated surfaces were characterized under SEM and by profilometry. The effect of water aging on the degree of conversion was measured by means of FTIR-ATR spectroscopy. An important increase in the degree of conversion was observed after aging. No significant differences in TBS were observed among the mechanical surface treatments, despite variations in surface roughness profiles. Phosphoric acid etching significantly improved repair bond strength values. The cohesive TBS of the material was only reached using resin bonding agents. Application of an intermediate bonding system plays a key role in achieving reliable repair bond strengths, whereas the kind of mechanical surface treatment appears to play a secondary role.

  13. Body Mass Index and Body Composition with Deuterium in Costa Rican Children

    International Nuclear Information System (INIS)

    Quintana-Guzmán, E.; Salas-Chaves, M. D. P.

    2015-01-01

    Body Mass Index (BMI) has been adopted as international measure for measuring adiposity in children with the disadvantage that it varies with age, sex and sexual maturation with no differentiation between fat mass and mass free of grease. The analysis of body composition allow to know if the overweight is due to fatty tissue being the deuterium isotope dilution a validated reference method using Infrared Spectrometry Transformed of Fourier (FTIR). We studied a total 118 boys and girls from 6 to 9 years old getting the values of z score of BMI for age and percentage of fat mass by FTIR. The results obtained in this study demonstrated that Costa Rica does not escape to the global problem of childhood obesity founding by BMI 18.6% of overweight and 10% of obesity and by body composition 9% of overweight and 57% of obesity. Isotopic deuterium dilution method demonstrated in this study to be more suitable for the analysis of obesity and overweight in children since BMI presented false positive and false negative results giving less accurate information of adiposity of the subject. (author)

  14. Alterations of body mass index and body composition in atomic bomb survivors.

    Science.gov (United States)

    Tatsukawa, Y; Misumi, M; Yamada, M; Masunari, N; Oyama, H; Nakanishi, S; Fukunaga, M; Fujiwara, S

    2013-08-01

    Obesity, underweight, sarcopenia and excess accumulation of abdominal fat are associated with a risk of death and adverse health outcomes. Our aim was to determine whether body mass index (BMI) and body composition, assessed with dual-energy X-ray absorptiometry (DXA), are associated with radiation exposure among atomic bomb (A-bomb) survivors. This was a cross-sectional study conducted in the Adult Health Study of the Radiation Effects Research Foundation. We examined 2686 subjects (834 men and 1852 women), aged 48-89 years (0-40 years at A-bomb exposure), for BMI analysis. Among them, 550 men and 1179 women underwent DXA in 1994-1996 and were eligible for a body composition study. After being adjusted for age and other potential confounding factors, A-bomb radiation dose was associated significantly and negatively with BMI in both sexes (P=0.01 in men, P=0.03 in women) and appendicular lean mass (Pbomb radiation exposure. We will need to conduct further studies to evaluate whether these alterations affect health status.

  15. Hand Grip Strength in Low, Medium, and High Body Mass Index Males and Females

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    Liao

    2016-01-01

    Full Text Available Background Hand grip strength (HGS is a predictor of upper extremity function and changes in muscle strength, physical movement and ability to undertake activities of daily living. Body mass index (BMI is a critical indicator of physical health; however, the relationship between HGS and BMI has not yet been thoroughly examined. Objectives The current study aims to compare HGS in low, medium, and high BMI males and females in both hands, and also investigates the correlation between HGS and anthropometric characteristics among the three BMI groups. Patients and Methods The study included 200 participants who were divided into three groups based on their BMI (60 low, 58 medium, and 82 high. HGS was assessed using a hand-held Jamar dynamometer. BMI was assessed by an electric body-weight height analysis machine. Data was analyzed using descriptive and inferential statistics at P 0.05. Weight and height strongly correlated with HGS for hands (correlation (r ranged from 0.000 - 0.775. Regression analysis showed that when using sex and BMI as independent variables for predicting the dependent variable HGS, the coefficient of the determinant R2 was 0.753 (P < 0.001. Conclusions The current study revealed that a significant difference existed in HGS among the low, medium, and high BMI groups. A positive correlation existed between HGS and weight and height, while sex was the most significant factor affecting HGS. These findings can serve as a reference to assess HGS prediction, whereby the sex effect should be considered.

  16. Effects of a physical activity programme on body perception and composition in overweight adolescents

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    Onofre Ricardo Contreras-Jordán

    2017-03-01

    Full Text Available Background The purpose of this study was to examine the effectiveness of a six months' physical activity programme for overweight and obese adolescents, in order to improve the perception of their own body image and composition between two groups of adolescents, and to check possible gender differences. Aims The aim is to improve the body perception and composition in overweight adolescents with a physical activity programme. Methods It was a quasi-experimental design, with a control group and intervention group. Measures of pre-test and post-test were taken. A total of 38 adolescents that belong to the first cycle of Compulsory Secondary aged 12–15, with a body mass index (BMI higher than the 85th percentile according to the WHO (World Health Organization, participated in the intervention. The anthropometric variables, height, weight, BMI, body fat percentage, and the circumference of the waist, hip, arm and medial calf, were measured pre- and post-treatment. The body image perception was measured using the Gardner test. The experimental group participated in the physical activity programme for a six months period. The physical activity intervention consisted of three sessions of 90 minutes each week in a sports centre. The structure of the sessions consisted of a warm-up (5–10 minutes, a main activity (60–70 minutes, combineding strength and cardiovascular training and a cool-down (7–10 minutes. Results After physical activity intervention the results showed significant improvements in the experimental group compared to the control group in the circumference of the waist, the hip, the arm, the medial calf (p<0.01 and as well as the fat percentage, the percentage of muscle mass (p<0.05. The results showed how the body image distortion presented a significant and negative correlation with the circumference of the waist (p<0.001, of the hips (p<0.01, and of the arm (p<0.001, differences were observed between gender. Conclusion Our study

  17. Effects of alfa-hydroxy-isocaproic acid on body composition, DOMS and performance in athletes

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    Karila Tuomo AM

    2010-01-01

    Full Text Available Abstract Background Alfa-Hydroxy-isocaproic acid (HICA is an end product of leucine metabolism in human tissues such as muscle and connective tissue. According to the clinical and experimental studies, HICA can be considered as an anti-catabolic substance. The present study investigated the effects of HICA supplementation on body composition, delayed onset of muscle soreness (DOMS and physical performance of athletes during a training period. Methods Fifteen healthy male soccer players (age 22.1+/-3.9 yr volunteered for the 4-week double-blind study during an intensive training period. The subjects in the group HICA (n = 8 received 583 mg of sodium salt of HICA (corresponding 500 mg of HICA mixed with liquid three times a day for 4 weeks, and those in the group PLACEBO (n = 7 received 650 mg of maltodextrin mixed with liquid three times a day for the same period. According to a weekly training schedule, they practiced soccer 3 - 4 times a week, had strength training 1 - 2 times a week, and had one soccer game during the study. The subjects were required to keep diaries on training, nutrition, and symptoms of DOMS. Body composition was evaluated with a dual-energy X-ray absorptiometry (DXA before and after the 4-week period. Muscle strength and running velocity were measured with field tests. Results As compared to placebo, the HICA supplementation increased significantly body weight (p th week of the treatment (p Conclusion Already a 4-week HICA supplementation of 1.5 g a day leads to small increases in muscle mass during an intensive training period in soccer athletes.

  18. Effect of Electrospun Nanofibers on the Short Beam Strength of Laminated Fiberglass Composite

    Science.gov (United States)

    Shinde, Dattaji K.

    High specific modulus and strength are the most desirable properties for the material used in structural applications. Composite materials exhibit these properties and over the last decade, their usage has increased significantly, particularly in automotive, defense, and aerospace applications. The major cause of failures in composite laminates is due to delaminations. Delamination in composite laminates can occur due to fatigue, low velocity impact and other loadings modes. Conventional methods like "through-the-thickness stitching" or "Z-Pinning" have limitations for improving flexural and interlaminar properties in woven composites due to the fact that while improving interlaminar properties, the presence of stitches or Z pins affects in-plane properties. This study investigates the flexural behavior of fiberglass composites interleaved with non-woven Tetra Ethyl Orthosilicate (TEOS) electrsopsun nanofibers (ENFs). TEOS ENFs were manufactured using an electrospinning technique and then sintered. Nanoengineered beams were fabricated by interleaving TEOS ENFs between the laminated fiberglass composites to improve the flexural properties. TEOS ENFs, resin film, and failed fiberglass laminated composites with and without nanofibers were characterized using SEM Imaging and ASTM standard testing methods. A hybrid composite was made by interleaving a non-woven sheet of TEOS ENFs between the fiberglass laminates with additional epoxy resin film and fabricated using the out of autoclave vacuum bagging method. Four commonly used stacking sequences of fiberglass laminates with and without nanofibers were used to study the progressive failure and deformation mechanics under flexural loadings. The experimental study has shown significant improvements in short beam strength and strain energy absorption in the nanoengineered laminated fiberglass composites before complete failure. The modes were investigated by performing detailed fractographic examination of failed specimens

  19. Creatine monohydrate supplementation does not increase muscle strength, lean body mass, or muscle phosphocreatine in patients with myotonic dystrophy type 1.

    Science.gov (United States)

    Tarnopolsky, Mark; Mahoney, Douglas; Thompson, Terry; Naylor, Heather; Doherty, Timothy J

    2004-01-01

    Creatine monohydrate (CrM) supplementation may increase strength in some types of muscular dystrophy. A recent study in myotonic muscular dystrophy type 1 (DM1) did not find a significant treatment effect, but measurements of muscle phosphocreatine (PCr) were not performed. We completed a randomized, double-blind, cross-over trial using 34 genetically confirmed adult DM1 patients without significant cognitive impairment. Participants received CrM (5 g, approximately 0.074 g/kg daily) and a placebo for each 4-month phase with a 6-week wash-out. Spirometry, manual muscle testing, quantitative isometric strength testing of handgrip, foot dorsiflexion, and knee extension, handgrip and foot dorsiflexion endurance, functional tasks, activity of daily living scales, body composition (total, bone, and fat-free mass), serum creatine kinase activity, serum creatinine concentration and clearance, and liver function tests were completed before and after each intervention, and muscle PCr/beta-adenosine triphosphate (ATP) ratios of the forearm flexor muscles were completed at the end of each phase. CrM supplementation did not increase any of the outcome measurements except for plasma creatinine concentration (but not creatinine clearance). Thus, CrM supplementation at 5 g daily does not have any effects on muscle strength, body composition, or activities of daily living in patients with DM1, perhaps because of a failure of the supplementation to increase muscle PCr/beta-ATP content.

  20. Bond strength of a composite resin to glass ionomer cements using different adhesive systems

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    Ana Carolina de Oliveira BECCI

    2017-08-01

    Full Text Available Abstract Introduction Glass ionomer cements are often used as a base or cavity lining prior to restorative material. Objective To evaluate the bond strength of a composite resin to different glass ionomer cements, when using a two-step conventional and self-etching adhesive systems. Material and method Three glass ionomer cements (Ketac Molar Easymix, Vitremer and Vitrebond, the composite resin Filtek Z350 XT and the adhesive systems Adper Single Bond 2, Clearfil SE Bond and Adper Easy One were used. As negative control, resin was bonded to cement without using an adhesive system. Holes (4 mm diameter, 2 mm deep prepared in acrilic bloks were filled with the glass ionomer cements (n=12/group. On the surface, an area of 1mm in diameter was delimited, the adhesive system was applied, and a specimen of composite resin with 1 mm height was made. After 24 hours storage (37 °C and 100% humidity, the microshear test was performed. Data were analyzed using two-way ANOVA and Tukey test for comparison between groups (α=0.05. Result The adhesive systems significantly improved the bond strenght of composite resin to glass ionomer cements (p≤0.001. There was no significant difference in bond strength when self-etching adhesive systems were compared with the simplified etch-and-rinse adhesive, except for Vitrebond where Clearfil SE Bond determined higher bond strength when compared to Adper Single Bond 2 (p=0.003. Conclusion Self-etching adhesive systems are a good option for establishing the bond between the composite resin and the glass ionomer cement.

  1. Multiparameter structural optimization of single-walled carbon nanotube composites: toward record strength, stiffness, and toughness.

    Science.gov (United States)

    Shim, Bong Sup; Zhu, Jian; Jan, Edward; Critchley, Kevin; Ho, Szushen; Podsiadlo, Paul; Sun, Kai; Kotov, Nicholas A

    2009-07-28

    Efficient coupling of mechanical properties of SWNTs with the matrix leading to the transfer of unique mechanical properties of SWNTs to the macroscopic composites is a tremendous challenge of today's materials science. The typical mechanical properties of known SWNT composites, such as strength, stiffness, and toughness, are assessed in an introductory survey where we focused on concrete numerical parameters characterizing mechanical properties. Obtaining ideal stress transfer will require fine optimization of nanotube-polymer interface. SWNT nanocomposites were made here by layer-by-layer (LBL) assembly with poly(vinyl alcohol) (PVA), and the first example of optimization in respect to key parameters determining the connectivity at the graphene-polymer interface, namely, degree of SWNT oxidation and cross-linking chemistry, was demonstrated. The resulting SWNT-PVA composites demonstrated tensile strength (σ(ult)) = 504.5 ± 67.3 MPa, stiffness (E) = 15.6 ± 3.8 GPa, and toughness (K) = 121.2 ± 19.2 J/g with maximum values recorded at σ(ult) = 600.1 MPa, E = 20.6 GPa, and K = 152.1 J/g. This represents the strongest and stiffest nonfibrous SWNT composites made to date outperforming other bulk composites by 2-10 times. Its high performance is attributed to both high nanotube content and efficient stress transfer. The resulting LBL composite is also one of the toughest in this category of materials and exceeding the toughness of Kevlar by 3-fold. Our observation suggests that the strengthening and toughening mechanism originates from the synergistic combination of high degree of SWNT exfoliation, efficient SWNT-PVA binding, crack surface roughening, and fairly efficient distribution of local stress over the SWNT network. The need for a multiscale approach in designing SWNT composites is advocated.

  2. Body composition and net energy requirements of Brazilian Somali lambs

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    Elzânia S. Pereira

    2014-12-01

    Full Text Available The aim of this study was to determine the energy requirements for maintenance (NEm and growth of 48 Brazilian Somali ram lambs with an average initial body weight of 13.47±1.76 kg. Eight animals were slaughtered at the trials beginning as a reference group to estimate the initial empty body weight (EBW and body composition. The remaining animals were assigned to a randomised block design with eight replications per block and five diets with increasing metabolisable energy content (4.93, 8.65, 9.41, 10.12 and 11.24 MJ/kg dry matter. The logarithm of heat production was regressed against metabolisable energy intake (MEI, and the NEm (kJ/kg0.75 EBW/day were estimated by extrapolation, when MEI was set at zero. The NEm was 239.77 kJ/kg0.75 EBW/day. The animal’s energy and EBW fat contents increased from 11.20 MJ/kg and 208.54 g/kg to 13.54 MJ/kg and 274.95 g/kg of EBW, respectively, as the BW increased from 13 to 28.70 kg. The net energy requirements for EBW gain increased from 13.79 to 16.72 MJ/kg EBW gain for body weights of 13 and 28.70 kg. Our study indicated the net energy requirements for maintenance in Brazilian Somali lambs were similar to the values commonly recommended by the United States’ nutritional system, but lower than the values recommended by Agricultural Research Council and Commonwealth Scientific and Industrial Research Organization. Net requirements for weight gain were less compared to the values commonly recommended by nutritional system of the United States.

  3. A modeling approach for compounds affecting body composition.

    Science.gov (United States)

    Gennemark, Peter; Jansson-Löfmark, Rasmus; Hyberg, Gina; Wigstrand, Maria; Kakol-Palm, Dorota; Håkansson, Pernilla; Hovdal, Daniel; Brodin, Peter; Fritsch-Fredin, Maria; Antonsson, Madeleine; Ploj, Karolina; Gabrielsson, Johan

    2013-12-01

    Body composition and body mass are pivotal clinical endpoints in studies of welfare diseases. We present a combined effort of established and new mathematical models based on rigorous monitoring of energy intake (EI) and body mass in mice. Specifically, we parameterize a mechanistic turnover model based on the law of energy conservation coupled to a drug mechanism model. Key model variables are fat-free mass (FFM) and fat mass (FM), governed by EI and energy expenditure (EE). An empirical Forbes curve relating FFM to FM was derived experimentally for female C57BL/6 mice. The Forbes curve differs from a previously reported curve for male C57BL/6 mice, and we thoroughly analyse how the choice of Forbes curve impacts model predictions. The drug mechanism function acts on EI or EE, or both. Drug mechanism parameters (two to three parameters) and system parameters (up to six free parameters) could be estimated with good precision (coefficients of variation typically mass and FM changes at different drug provocations using a similar model for man. Surprisingly, model simulations indicate that an increase in EI (e.g. 10 %) was more efficient than an equal lowering of EI. Also, the relative change in body mass and FM is greater in man than in mouse at the same relative change in either EI or EE. We acknowledge that this assumes the same drug mechanism impact across the two species. A set of recommendations regarding the Forbes curve, vehicle control groups, dual action on EI and loss, and translational aspects are discussed. This quantitative approach significantly improves data interpretation, disease system understanding, safety assessment and translation across species.

  4. Predicting the tensile strength of A UD basalt/ epoxy composite used for the confinement of concrete structures

    Science.gov (United States)

    Ciniņa, I.; Zīle, O.; Andersons, J.

    2013-01-01

    The principal aim of the present research was to predict the strength of UD basalt fiber/epoxy matrix composites in tension along the reinforcement direction. Tension tests on single basalt fibers were performed to determine the functional form of their strength distribution and to evaluate the parameters of the distribution. Also, microbond tests were carried out to assess the interfacial shear strength of the fibers and polymer matrix. UD composite specimens were produced and tested for the longitudinal tensile strength. The predicted strength of the composite was found to exceed the experimental values by ca. 20%, which can be explained by imperfections in the fiber alignment, impregnation, and adhesion in the composite specimens.

  5. A study on the compatibility between one-bottle dentin adhesives and composite resins using micro-shear bond strength.

    Science.gov (United States)

    Song, Minju; Shin, Yooseok; Park, Jeong-Won; Roh, Byoung-Duck

    2015-02-01

    This study was performed to determine whether the combined use of one-bottle self-etch adhesives and composite resins from same manufacturers have better bond strengths than combinations of adhesive and resins from different manufacturers. 25 experimental micro-shear bond test groups were made from combinations of five dentin adhesives and five composite resins with extracted human molars stored in saline for 24 hr. Testing was performed using the wire-loop method and a universal testing machine. Bond strength data was statistically analyzed using two way analysis of variance (ANOVA) and Tukey's post hoc test. Two way ANOVA revealed significant differences for the factors of dentin adhesives and composite resins, and significant interaction effect (p composite resin (p composite resin than other manufacturer's composite resin. Not all combinations of adhesive and composite resin by same manufacturers failed to show significantly higher bond strengths than mixed manufacturer combinations.

  6. Bioactive hydroxyapatite/graphene composite coating and its corrosion stability in simulated body fluid

    Energy Technology Data Exchange (ETDEWEB)

    Janković, Ana; Eraković, Sanja [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11 000 Belgrade (Serbia); Mitrić, Miodrag [Vinča Institute of Nuclear Sciences, University of Belgrade, Mike Petrovića Alasa 12-14, 11 000 Belgrade (Serbia); Matić, Ivana Z.; Juranić, Zorica D. [Institute of Oncology and Radiology of Serbia, Pasterova 14, 11 000 Belgrade (Serbia); Tsui, Gary C.P.; Tang, Chak-yin [Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); Mišković-Stanković, Vesna [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11 000 Belgrade (Serbia); Rhee, Kyong Yop, E-mail: rheeky@khu.ac.kr [Department of Mechanical Engineering, Kyung Hee University, Yongin 449-701 (Korea, Republic of); Park, Soo Jin [Chemistry, College of Natural Sciences, Inha University, Incheon 402-751 (Korea, Republic of)

    2015-03-05

    Highlights: • Bioactive HAP/Gr coating on Ti was successfully obtained by EPD. • Increased fracture toughness of the HAP/Gr coating compared to pure HAP coating. • HAP/Gr coating exhibited superior biomimetic mineralization vs. pure HAP coating. • Gr improved the mechanical properties and thermal stability of HAP/Gr coating. • HAP/Gr coating was classified as non-cytotoxic against the targeted PBMC. - Abstract: The hydroxyapatite/graphene (HAP/Gr) composite was electrodeposited on Ti using the electrophoretic deposition process to obtain uniform bioactive coating with improved mechanical strength and favorable corrosion stability in simulated body fluid (SBF). Incorporation of Gr was verified by Raman spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray photoelectron analysis. The HAP/Gr composite coating exhibited reduced surface cracks, nearly double the hardness, and elastic modulus increased by almost 50% compared to pure HAP coating, as estimated by a nanoindentation test. The bioactive HAP/Gr composite coating provided a newly formed apatite layer in SBF with enhanced corrosion stability, as evidenced by electrochemical impedance spectroscopy. The thermal stability of the HAP/Gr coating was improved in comparison to the pure HAP coating, and the Ca/P ratio was closer to the stoichiometric value. No antibacterial activity against Staphylococcus aureus or Escherichia coli could be verified. The HAP/Gr composite coating was classified as non-cytotoxic when tested against healthy peripheral blood mononuclear cells (PBMC)

  7. Bioactive hydroxyapatite/graphene composite coating and its corrosion stability in simulated body fluid

    International Nuclear Information System (INIS)

    Janković, Ana; Eraković, Sanja; Mitrić, Miodrag; Matić, Ivana Z.; Juranić, Zorica D.; Tsui, Gary C.P.; Tang, Chak-yin; Mišković-Stanković, Vesna; Rhee, Kyong Yop; Park, Soo Jin

    2015-01-01

    Highlights: • Bioactive HAP/Gr coating on Ti was successfully obtained by EPD. • Increased fracture toughness of the HAP/Gr coating compared to pure HAP coating. • HAP/Gr coating exhibited superior biomimetic mineralization vs. pure HAP coating. • Gr improved the mechanical properties and thermal stability of HAP/Gr coating. • HAP/Gr coating was classified as non-cytotoxic against the targeted PBMC. - Abstract: The hydroxyapatite/graphene (HAP/Gr) composite was electrodeposited on Ti using the electrophoretic deposition process to obtain uniform bioactive coating with improved mechanical strength and favorable corrosion stability in simulated body fluid (SBF). Incorporation of Gr was verified by Raman spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray photoelectron analysis. The HAP/Gr composite coating exhibited reduced surface cracks, nearly double the hardness, and elastic modulus increased by almost 50% compared to pure HAP coating, as estimated by a nanoindentation test. The bioactive HAP/Gr composite coating provided a newly formed apatite layer in SBF with enhanced corrosion stability, as evidenced by electrochemical impedance spectroscopy. The thermal stability of the HAP/Gr coating was improved in comparison to the pure HAP coating, and the Ca/P ratio was closer to the stoichiometric value. No antibacterial activity against Staphylococcus aureus or Escherichia coli could be verified. The HAP/Gr composite coating was classified as non-cytotoxic when tested against healthy peripheral blood mononuclear cells (PBMC)

  8. Changes in body weight, body composition, and eating attitudes in high school wrestlers.

    Science.gov (United States)

    Shriver, Lenka Humenikova; Betts, Nancy Mulhollen; Payton, Mark Edward

    2009-08-01

    Many wrestlers engage in chronic dieting and rapid "weight cutting" throughout the year to compete in a category below their natural weight. Such weight-management practices have a negative influence on their health and nutritional status, so the National Wrestling Coaches Association implemented a new weight-management program for high school wrestlers in 2006. The purpose of this study was to determine whether seasonal changes in weight, body fat, and eating attitudes occur among high school wrestlers after the implementation of the new weight-management rule. Fifteen high school wrestlers participated in the study. Their weight, body composition, and eating attitudes were measured preseason, in-season, and off-season. Body fat was assessed using dual-energy X-ray absorptiometry. Attitudes toward dieting, food, and body weight were assessed using the Eating Attitude Test (EAT). No significant changes in body fat were detected from preseason to off-season. Weight increased from preseason to in-season (p < .05) and off-season (p < .05). Although the EAT score did not change significantly from preseason to off-season, 60% reported "thinking about burning up calories when exercising" during preseason, and only 40% felt that way during the season (p < .05) and 47% during, off-season (p < .05). The wrestlers experienced a significant weight gain from preseason to off-season with no significant changes in body fat. Their eating attitudes did not change significantly from preseason to off-season in this study, but further research using a large sample of high school wrestlers is warranted to confirm these findings.

  9. Comparison of tensile strength of different carbon fabric reinforced epoxy composites

    Directory of Open Access Journals (Sweden)

    Jane Maria Faulstich de Paiva

    2006-03-01

    Full Text Available Carbon fabric/epoxy composites are materials used in aeronautical industry to manufacture several components as flaps, aileron, landing-gear doors and others. To evaluate these materials become important to know their mechanical properties, for example, the tensile strength. Tensile tests are usually performed in aeronautical industry to determinate tensile property data for material specifications, quality assurance and structural analysis. For this work, it was manufactured four different laminate families (F155/PW, F155/HS, F584/PW and F584/HS using pre-impregnated materials (prepregs based on F155TM and F584TM epoxy resins reinforced with carbon fiber fabric styles Plain Weave (PW and Eight Harness Satin (8HS. The matrix F155TM code is an epoxy resin type DGEBA (diglycidil ether of bisphenol A that contains a curing agent and the F584TM code is a modified epoxy resin type. The laminates were obtained by handing lay-up process following an appropriate curing cycle in autoclave. The samples were evaluated by tensile tests according to the ASTM D3039. The F584/PW laminates presented the highest values of tensile strength. However, the highest modulus results were determined for the 8HS composite laminates. The correlation of these results emphasizes the importance of the adequate combination of the polymeric matrix and the reinforcement arrangement in the structural composite manufacture. The microscopic analyses of the tested specimens show valid failure modes for composites used in aeronautical industry.

  10. Strength and deformability of concrete beams reinforced by non-metallic fiber and composite rebar

    Science.gov (United States)

    Kudyakov, K. L.; Plevkov, V. S.; Nevskii, A. V.

    2015-01-01

    Production of durable and high-strength concrete structures with unique properties has always been crucial. Therefore special attention has been paid to non-metallic composite and fiber reinforcement. This article describes the experimental research of strength and deformability of concrete beams with dispersed and core fiber-based reinforcement. As composite reinforcement fiberglass reinforced plastic rods with diameters 6 mm and 10 mm are used. Carbon and basalt fibers are used as dispersed reinforcement. The developed experimental program includes designing and production of flexural structures with different parameters of dispersed fiber and composite rebar reinforcement. The preliminary testing of mechanical properties of these materials has shown their effectiveness. Structures underwent bending testing on a special bench by applying flexural static load up to complete destruction. During the tests vertical displacements were recorded, as well as value of actual load, slippage of rebars in concrete, crack formation. As a result of research were obtained structural failure and crack formation graphs, value of fracture load and maximum displacements of the beams at midspan. Analysis of experimental data showed the effectiveness of using dispersed reinforcement of concrete and the need for prestressing of fiberglass composite rebar.

  11. BODY BUILD AND BODY COMPOSITION VS. PHYSICAL CAPACITY IN YOUNG JUDO CONTESTANTS COMPARED TO UNTRAINED SUBJECTS

    Directory of Open Access Journals (Sweden)

    G. Lech

    2011-11-01

    Full Text Available The aim of the present study was to (1 find differences in body build and aerobic and anaerobic capacity between young judoists and untrained peers; (2 compare correlations for indicators of body build with indicators of aerobic and anaerobic capacity among the group of trained and untrained subjects. The study group comprised 18 subjects selected during a competitive period, who had taken at least fifth place in national judo tournaments. Their training experience ranged from 6 to 11 years, 8 to 10 hours a week. The control group was composed of 18 untrained students from one of the schools included in the study. Their body height and mass (BM did not differ compared to judoists. A body composition chart was employed for analysis of body build and body composition. Physiological investigations encompassed measurements of anaerobic (Wingate test and aerobic (graded exercise test on cycle ergometer capacity. Judo contestants are typically characterized by higher BMI, fat-free mass and fat-free mass index compared to the untrained. Compared to the group of untrained peers, young athletes in this sport are distinguished by the time needed to generate peak power. This difference is not observed in the indices characterising aerobic capacity. The level of the indices of body build and composition in young judo contestants shows a moderate and strong correlation with indices of anaerobic and aerobic capacity. The amount of total work in the Wingate test was positively correlated with BMI (r=0.65, p<0.01, fat-free mass index (r=0.63, p<0.01, body mass (r=0.49, p<0.05, fat mass index (r=0.49, p<0.05 and percentage of fat (r=0.48, p<0.05. Maximal peak anaerobic power was positively correlated with fat-free mass index (r=0.48, p<0.05 and percentage of fat (r=0.50, p<0.05. A strong negative correlation between ·VO2max with body mass (r=-0.75, p<0.001, BMI (r=-0.72, p<0.001, moderate correlation with PF%(r=-0.64, p<0.01, fat-free mass index (r=-0.52, p<0

  12. Bond strength of composite resin to enamel: assessment of two ethanol wet-bonding techniques.

    Directory of Open Access Journals (Sweden)

    Maryam Khoroushi

    2014-04-01

    Full Text Available Ethanol wet-bonding (EWB technique has been stated to decrease degradation of resin-dentin bond. This study evaluated the effect of two EWB techniques on composite resin-to-enamel bond strength.Silicon carbide papers were used to produce flat enamel surfaces on the buccal faces of forty-five molars. OptiBond FL (OFL adhesive was applied on enamel surfaces in three groups of 15 namely: Enamel surface and OFL (control;Protocol 1 of the EWB technique: absolute ethanol was applied to water-saturated acid-etched enamel surfaces for 1 minute before the application of ethanol-solvated hydrophobic adhesive resin of OFL 3 times;Protocol 2: progressive ethanol replacement; water was gradually removed from the enamel matrix using ascending ethanol concentrations before OFL application. Composite build-ups were made and the specimens were stored for 24 hours at 37°C and 100% relative humidity. Shear bond strength test was performed using a universal testing machine at 1 mm/min crosshead speed. Fracture patterns were evaluated microscopically. Data were analyzed with one-way ANOVA and Fisher's exact test (α=0.05.There were no significant differences in bond strength between the groups (P=0.73. However, regarding failure patterns, the highest cohesive enamel fractures were recorded in groups 2 and 3.In this study, although both methods of EWB did not influence immediate bond strength of composite resin to enamel, the majority of failure patterns occurred cohesively in enamel.

  13. Efficacy of ceramic repair material on the bond strength of composite resin to zirconia ceramic.

    Science.gov (United States)

    Kirmali, Omer; Kapdan, Alper; Harorli, Osman Tolga; Barutcugil, Cagatay; Ozarslan, Mehmet Mustafa

    2015-01-01

    The aim of this study was to evaluate the shear bond strength of composite resin in five different repair systems. Sixty specimens (7 mm in diameter and 3 mm in height) of zirconia ceramic were fabricated. All specimen surfaces were prepared with a 30 µm fine diamond rotary cutting instrument with water irrigation for 10 s and dried with oil-free air. Specimens were then randomly divided into six groups for the following different intra-oral repair systems (n = 10): Group 1, control group; Group 2, Cojet system (3M ESPE, Seefeld, Germany); Group 3, Cimara® System (Voco, Cuxhaven, Germany); Group 4, Z-Prime Plus System (Bisco Inc., Schaumburg, IL); Group 5, Clearfil™ System (Kuraray, Osaka, Japan); and Group 6, Z-Bond System (Danville, CA). After surface conditioning, a composite resin Grandio (Voco, Cuxhaven, Germany) was applied to the zirconia surface using a cylindrical mold (5 mm in diameter and 3 mm in length) and incrementally filled up, according to the manufacturer's instructions of each intra-oral system. Each specimen was subjected to a shear load at a crosshead speed of 1 mm/min until fracture. One-way analysis of variance (ANOVA) and Tukey post-hoc tests were used to analyze the bond strength values. There were significant differences between Groups 2-6 and Group 1. The highest bond strength values were obtained with Group 2 (17.26 ± 3.22) and Group 3 (17.31 ± 3.62), while the lowest values were observed with Group 1 (8.96 ± 1.62) and Group 6 (12.85 ± 3.95). All repair systems tested increased the bond strength values between zirconia and composite resin that used surface grinding with a diamond bur.

  14. Directly deposited graphene nanowalls on carbon fiber for improving the interface strength in composites

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Yao [Department of Building Materials Engineering, College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); Key Laboratory of Multi-Scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714 (China); Chu, Jin; Li, Chaolong, E-mail: cmf-210@126.com, E-mail: lichaolong@cigit.ac.cn; Piao, Mingxing; Zhang, Heng; Shi, Haofei [Key Laboratory of Multi-Scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714 (China); Chen, Mingfeng, E-mail: cmf-210@126.com, E-mail: lichaolong@cigit.ac.cn; Mao, Weijie [Department of Building Materials Engineering, College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); Liu, Bao Sheng [Avic Beijing Aeronautical Manufacturing Technology Research Institute, Beijing 100024 (China)

    2016-05-23

    Graphene nanowalls (GNWs) were grown directly on carbon fibers using a chemical vapor deposition technique which is simple and catalyst-free. We found that there is very strong π-π stacking which is a benefit for the GNWs/carbon fiber interface. This single modified filament then was embedded into an epoxy matrix to be a single-fiber composite in which was formed a “tenon-mortise” structure. Such a “tenon-mortise” model provides a simple, stable, and powerful connection between carbon fiber and the epoxy matrix. In addition, it was demonstrated that the epoxy matrix can be well embedded into GNWs through a field emission scanning electron microscope. The results of the single-fiber composite tests indicated that the interfacial strength of the composites was immensely improved by 173% compared to those specimens without GNWs.

  15. The Composition and Temperature Effects on the Ultra High Strength Stainless Steel Design

    Science.gov (United States)

    Xu, W.; Del Castillo, P. E. J. Rivera Díaz; van der Zwaag, S.

    Alloy composition and heat treatment are of paramount importance to determining alloy properties. Their control is of great importance for new alloy design and industrial fabrication control. A base alloy utilizing MX carbide is designed through a theory guided computational approach coupling a genetic algorithm with optimization criteria based on thermodynamic, kinetic and mechanical principles. The combined effects of 11 alloying elements (Al, C, Co, Cr, Cu, Mo, Nb, Ni, Si, Ti and V) are investigated in terms of the composition optimization criteria: the martensite start (Ms) temperature, the suppression of undesirable phases, the Cr concentration in the matrix and the potency of the precipitation strengthening contribution. The results show the concentration sensitivities of each component and also point out new potential composition domains for further strength increase. The aging temperature effect is studied and the aging temperature industrially followed is recovered.

  16. Strength of SiCf-SiCm composite tube under uniaxial and multiaxial loading

    Science.gov (United States)

    Shapovalov, Kirill; Jacobsen, George M.; Alva, Luis; Truesdale, Nathaniel; Deck, Christian P.; Huang, Xinyu

    2018-03-01

    The authors report mechanical strength of nuclear grade silicon carbide fiber reinforced silicon carbide matrix composite (SiCf-SiCm) tubing under several different stress states. The composite tubing was fabricated via a Chemical Vapor Infiltration (CVI) process, and is being evaluated for accident tolerant nuclear fuel cladding. Several experimental techniques were applied including uniaxial tension, elastomer insert burst test, open and closed end hydraulic bladder burst test, and torsion test. These tests provided critical stress and strain values at proportional limit and at ultimate failure points. Full field strain measurements using digital image correlation (DIC) were obtained in order to acquire quantitative information on localized deformation during application of stress. Based on the test results, a failure map was constructed for the SiCf-SiCm composites.

  17. Notched Strength of Woven Fabric Kenaf Composite Plates with Different Stacking Sequences and Hole Sizes

    Directory of Open Access Journals (Sweden)

    Hans Romayne Anders

    2016-01-01

    Full Text Available Advantages of using kenaf fibres over synthetic fibres in composites manufacturing are relatively cheap, less abrasive and hazardous during handling, and renewable materials. Current work investigates parametric effects on notched strength of woven fabric kenaf polymer composites plates with variation of lay-up types, notch sizes and plate thickness. Testing coupons are prepared using hand lay-up technique and circular notch were drilled prior to mechanical testing. Stress concentration at the notch edge promotes micro-damage event as tensile loading was applied leading to crack initiation and propagations across the plate width. It is suggested that woven fabric kenaf polymer composites are potentially used in low and medium load bearing applications.

  18. A comparison of three methods to assess body composition.

    Science.gov (United States)

    Tewari, Nilanjana; Awad, Sherif; Macdonald, Ian A; Lobo, Dileep N

    2018-03-01

    The aim of this study was to compare the accuracy of measurements of body composition made using dual x-ray absorptiometry (DXA), analysis of computed tomography (CT) scans at the L3 vertebral level, and bioelectrical impedance analysis (BIA). DXA, CT, and BIA were performed in 47 patients recruited from two clinical trials investigating metabolic changes associated with major abdominal surgery or neoadjuvant chemotherapy for esophagogastric cancer. DXA was performed the week before surgery and before and after commencement of neoadjuvant chemotherapy. BIA was performed at the same time points and used with standard equations to calculate fat-free mass (FFM). Analysis of CT scans performed within 3 mo of the study was used to estimate FFM and fat mass (FM). There was good correlation between FM on DXA and CT (r 2  = 0.6632; P FFM on DXA and CT (r 2  = 0.7634; P FFM on DXA and BIA (r 2  = 0.6275; P FFM on CT and BIA also was significant (r 2  = 0.2742; P FFM on DXA and CT, average bias was -0.1477, with LOA of -8.621 to 8.325. For FFM on DXA and BIA, average bias was -3.792, with LOA of -15.52 to 7.936. For FFM on CT and BIA, average bias was -2.661, with LOA of -22.71 to 17.39. Although a systematic error underestimating FFM was demonstrated with BIA, it may be a useful modality to quantify body composition in the clinical situation. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Effect of sodium ascorbate on the bond strength of silorane and methacrylate composites after vital bleaching

    Directory of Open Access Journals (Sweden)

    Eda Guler

    2013-07-01

    Full Text Available We investigated the effect of sodium ascorbate (SA on the microtensile bond strengths (MTBSs of different composites to bovine enamel after vital bleaching with hydrogen peroxide (HP or carbamide peroxide (CP. Thirty bovine incisors were randomly divided into five groups and treated with no bleaching application (control, 35% HP alone, 35% HP + 10% SA for 10 minutes (HP + SA, 16% CP alone, or 16% CP + 10% SA for 10 minutes (CP + SA. Specimens were restored with Silorane adhesive and Filtek Silorane composite (designated as S / group or with Clearfil SE bond and Filtek Supreme XT (designated as F / group. Composite build-up was created on the enamel. Sectioned specimens (n = 10 per group; 1 mm2; cross-sectional area were created and stressed in a universal testing machine at 1 mm/min crosshead speed. The application of 10% SA immediately after bleaching with 16% CP or 35% HP increased the enamel MTBS, regardless of the adhesive / composite resin used. The resulting MTBS values were similar to those of the control groups. Use of 16% CP and 35% HP alone decreased the enamel MTBS, regardless of the adhesive / composite resin used, with F / CP + SA = F / HP + SA = F / CP = S / CP + SA = S / HP + SA = S / C > S / CP = S / HP = F / CP = F / HP (p < 0.05. We concluded that the application of SA for 10 minutes immediately after vital bleaching increases the enamel BS for dimethacrylate- and silorane-based composites

  20. Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded with Nano-filled Composites

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh Ahmad Akhoundi

    2013-01-01

    Full Text Available Objectives: The purpose of this study was to evaluate the shear bond strength (SBS of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Materials and Methods: Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel were used in groups II and III respectively. The teeth were stored in distilled water at 37°C for 24 hours, thermocycled in distilled water and debonded with a universal testing machine at a crosshead speed of 1 mm/min. The adhesive remnant index (ARI was also evaluated using a stereomicroscope. Results: AELITE Aesthetic Enamel nano-composite revealed a SBS value of 8.44±2.09 MPa, which was higher than Transbond XT (6.91± 2.13 and Filtek TM Supreme XT (6.04± 2.01. Statistical analysis revealed a significant difference between groups II and III (P 0.05. Evaluation of ARI showed that Transbond XT left fewer adhesive remains on teeth after debonding. Conclusion: Results of this study indicate that the aforementioned nano-composites can be successfully used for bonding orthodontic brackets.

  1. Evaluation of shear bond strength of orthodontic brackets bonded with nano-filled composites.

    Science.gov (United States)

    Chalipa, Javad; Akhondi, Mohammad Sadegh Ahmad; Arab, Sepideh; Kharrazifard, Mohammad Javad; Ahmadyar, Maryam

    2013-09-01

    The purpose of this study was to evaluate the shear bond strength (SBS) of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT) was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel) were used in groups II and III respectively. The teeth were stored in distilled water at 37°C for 24 hours, thermocycled in distilled water and debonded with a universal testing machine at a crosshead speed of 1 mm/min. The adhesive remnant index (ARI) was also evaluated using a stereomicroscope. AELITE Aesthetic Enamel nano-composite revealed a SBS value of 8.44±2.09 MPa, which was higher than Transbond XT (6.91±2.13) and Filtek TM Supreme XT (6.04±2.01). Statistical analysis revealed a significant difference between groups II and III (P 0.05). Evaluation of ARI showed that Transbond XT left fewer adhesive remains on teeth after debonding. Results of this study indicate that the aforementioned nano-composites can be successfully used for bonding orthodontic brackets.

  2. Microshear bond strength of resin composite to teeth affected by molar hypomineralization using 2 adhesive systems.

    Science.gov (United States)

    William, Vanessa; Burrow, Michael F; Palamara, Joseph E A; Messer, Louise B

    2006-01-01

    When restoring hypomineralized first permanent molars, placement of cavo-surface margins can be difficult to ascertain due to uncertainty of the bonding capability of the tooth surface. The purpose of this study was to investigate the adhesion of resin composite bonded to control and hypomineralized enamel with an all-etch single-bottle adhesive or self-etching primer adhesive. Specimens of control enamel (N=44) and hypomineralized enamel (N=45) had a 0.975-mm diameter composite rod (Filtek Supreme Universal Restorative) bonded with either 3M ESPE Single Bond or Clearfil SE Bond following manufacturers' instructions. Specimens were stressed in shear at 1 mm/min to failure (microshear bond strength). Etched enamel surfaces and enamel-adhesive interfaces were examined under scanning electron microscopy. The microshear bond strength (MPa) of resin composite bonded to hypomineralized enamel was significantly lower than for control enamel (3M ESPE Single Bond=7.08 +/- 4.90 vs 16.27 +/- 10.04; Clearfil SE Bond=10.39 +/- 7.56 vs 19.63 +/- 7.42; P=.001). Fractures were predominantly adhesive in control enamel and cohesive in hypomineralized enamel. Scotchbond etchant produced deep interprismatic and intercrystal porosity in control enamel and shallow etch patterns with minimal intercrystal porosity in hypomineralized enamel. Control enamel appeared almost unaffected by SE Primer; hypomineralized enamel showed shallow etching. The hypomineralized enamel-adhesive interface was porous with cracks in the enamel. The control enamel-adhesive interface displayed a hybrid layer of even thickness. The microshear bond strength of resin composite bonded to hypomineralized enamel was significantly lower than for control enamel. This was supported by differences seen in etch patterns and at the enamel-adhesive interface.

  3. Immediate Repair Bond Strength of Fiber-reinforced Composite after Saliva or Water Contamination.

    Science.gov (United States)

    Bijelic-Donova, Jasmina; Flett, Andrew; Lassila, Lippo V J; Vallittu, Pekka K

    2018-05-31

    This in vitro study aimed to evaluate the shear bond strength (SBS) of particulate filler composite (PFC) to saliva- or water-contaminated fiber-reinforced composite (FRC). One type of FRC substrate with semi-interpenetrating polymer matrix (semi-IPN) (everStick C&B) was used in this investigation. A microhybrid PFC (Filtek Z250) substrate served as control. Freshly cured PFC and FRC substrates were first subjected to different contamination and surface cleaning treatments, then the microhybrid PFC restorative material (Filtek Z250) was built up on the substrates in 2-mm increments and light cured. Uncontaminated and saliva- or water-contaminated substrate surfaces were either left untreated or were cleaned via phosphoric acid etching or water spray accompanied with or without adhesive composite application prior applying the adherent PFC material. SBS was evaluated after thermocycling the specimens (6000 cycles, 5°C and 55°C). Three-way ANOVA showed that both the surface contamination and the surface treatment signficantly affected the bond strength (p contamination reduced the SBS more than did the water contamination. SBS loss after saliva contamination was 73.7% and 31.3% for PFC and FRC, respectively. After water contamination, SBS loss was 17.2% and 13.3% for PFC and FRC, respectively. The type of surface treatment was significant for PFC (p contamination of freshly cured PFC or semi-IPN FRC, surfaces should be re-prepared via phosphoric acid etching, water cleaning, drying, and application of adhesive composite in order to recover optimal bond strength.

  4. Effect of universal adhesive etching modes on bond strength to dual-polymerizing composite resins.

    Science.gov (United States)

    Michaud, Pierre-Luc; Brown, Matthew

    2018-04-01

    Information is lacking as to the effect on bond strength of the etching modes of universal adhesives when they are used to bond dual-polymerizing composite resins to dentin. The purpose of this in vitro study was to investigate the bonding of dual-polymerizing foundation composite resins to dentin when universal bonding agents are used in self-etch or etch-and-rinse modes. Sixty caries-free, extracted third molar teeth were sectioned transversely in the apical third of the crown and allocated to 12 groups (n=5). Three different bonding agents