WorldWideScience

Sample records for strength influences outcomes

  1. Does cruciate retention primary total knee arthroplasty affect proprioception, strength and clinical outcome?

    Science.gov (United States)

    Vandekerckhove, Pieter-Jan T K; Parys, Roel; Tampere, Thomas; Linden, Patrick; Van den Daelen, Luc; Verdonk, Peter C

    2015-06-01

    It remains unclear what the contribution of the PCL is in total knee arthroplasty (TKA). The goal of this study was to investigate the influence of the PCL in TKA in relationship to clinical outcome, strength and proprioception. Two arthroplasty designs were compared: a posterior cruciate-substituting (PS) and a posterior cruciate-retaining (CR) TKA. A retrospective analysis was performed of 27 CR and 18 PS implants with a minimum of 1 year in vivo. Both groups were compared in terms of clinical outcome (range of motion, visual analogue scale for pain, Hospital for Special Surgery Knee Scoring system, Lysholm score and Knee Injury and Osteoarthritis Outcome Score), strength (Biodex System 3 Dynamometer(®)) and proprioception (balance and postural control using the Balance Master system(®)). Each design was also compared to the non-operated contralateral side in terms of strength and proprioception. There were no significant differences between both designs in terms of clinical outcome and strength. In terms of proprioception, only the rhythmic weight test at slow and moderate speed shifting from left to right was significant in favour of the CR design. None of the unilateral stance tests showed any significant difference between both designs. There was no difference in terms of strength and proprioception between the operated side and the non-operated side. Retaining the PCL in TKA does not result in an improved performance in terms of clinical outcome and proprioception and does not show any difference in muscle strength. III.

  2. Physical activity, but not sedentary time, influences bone strength in late adolescence.

    Science.gov (United States)

    Tan, Vina Ps; Macdonald, Heather M; Gabel, Leigh; McKay, Heather A

    2018-03-20

    Physical activity is essential for optimal bone strength accrual, but we know little about interactions between physical activity, sedentary time, and bone outcomes in older adolescents. Physical activity (by accelerometer and self-report) positively predicted bone strength and the distal and midshaft tibia in 15-year-old boys and girls. Lean body mass mediated the relationship between physical activity and bone strength in adolescents. To examine the influence of physical activity (PA) and sedentary time on bone strength, structure, and density in older adolescents. We used peripheral quantitative computed tomography to estimate bone strength at the distal tibia (8% site; bone strength index, BSI) and tibial midshaft (50% site; polar strength strain index, SSI p ) in adolescent boys (n = 86; 15.3 ± 0.4 years) and girls (n = 106; 15.3 ± 0.4 years). Using accelerometers (GT1M, Actigraph), we measured moderate-to-vigorous PA (MVPA Accel ), vigorous PA (VPA Accel ), and sedentary time in addition to self-reported MVPA (MVPA PAQ-A ) and impact PA (ImpactPA PAQ-A ). We examined relations between PA and sedentary time and bone outcomes, adjusting for ethnicity, maturity, tibial length, and total body lean mass. At the distal tibia, MVPA Accel and VPA Accel positively predicted BSI (explained 6-7% of the variance, p accounting for lean mass. Sedentary time did not independently predict bone strength at either site. Greater tibial bone strength in active adolescents is mediated, in part, by lean mass. Despite spending most of their day in sedentary pursuits, adolescents' bone strength was not negatively influenced by sedentary time.

  3. Promoting positive outcomes through strengths interventions : A literature review

    NARCIS (Netherlands)

    Ghielen, S.T.S.; van Woerkom, M.; Meyers, M.C.

    2018-01-01

    This paper reviews studies of strengths interventions published between 2011 and 2016. Strengths interventions aim to promote well-being or other positive outcomes by facilitating strengths identification, and sometimes also strengths use and/or development. The present review provides an overview

  4. G×E Interaction Influences Trajectories of Hand Grip Strength

    DEFF Research Database (Denmark)

    Petersen, Inge; Pedersen, Nancy L; Rantanen, Taina

    2016-01-01

    Age-related decline in grip strength predicts later life disability, frailty, lower well-being and cognitive change. While grip strength is heritable, genetic influence on change in grip strength has been relatively ignored, with non-shared environmental influence identified as the primary contri...

  5. Long-term outcome of muscle strength in ulnar and median nerve injury: Comparing manual muscle strength testing, grip and pinch strength dynamometers and a new intrinsic muscle strength dynamometer

    NARCIS (Netherlands)

    A.R. Schreuders (Ton); M.E. Roebroeck (Marij); J.B. Jaquet (Jean); S.E.R. Hovius (Steven); H.J. Stam (Henk)

    2004-01-01

    textabstractObjective: To compare the outcome of muscle strength with manual muscle strength testing grip and pinch strength measurements and a dynamometer which allows for measurements of the intrinsic muscles of the hand in isolation (the Rotterdam Intrinsic Hand Myometer, RIHM). Methods:

  6. INFLUENCE OF STRENGTH TRAINING PROGRAM ON ISOMETRIC MUSCLE STRENGTH IN YOUNG ATHLETES

    Directory of Open Access Journals (Sweden)

    Dragan Radovanovic

    2007-10-01

    Full Text Available Strength training, or resistance training, is a form of physical conditioning used to increase the ability to resist force. Since muscular strength is required for success in many sports, it is logical to assume that stronger and more powerful young athletes will achieve better results. The aim of the study was to examine the effects of strength training on young athletes. An eight-week strength training program for developing muscle strength was performed in this study. Training protocol was designed specifically for young adolescent’s athletes. The program consisted of exercises for lower and upper body, abdominal and lower back muscles. The programs did not involve the maximal (1-3 repetitions maximum and other very hard intensity exercises that may had negative effect on young athletes. The results showed that strength training program had positive effects on maximal isometric muscle force (Fmax and motor skill. The increase presents the combined influence of strength training and growth.

  7. Leg strength and lean mass symmetry influences kicking performance in Australian football.

    Science.gov (United States)

    Hart, Nicolas H; Nimphius, Sophia; Spiteri, Tania; Newton, Robert U

    2014-01-01

    Differential loading patterns during game-based participation may produce or exacerbate strength imbalances between the lower limbs. It is currently unknown whether such imbalances are functionally beneficial or detrimental to performance. This study assessed the influence of lower limb strength and lean mass symmetry on kicking accuracy in Australian Football. Thirty-one Australian footballers were required to perform a kicking assessment, producing ten drop punt kicks over twenty metres to a player target. Athletes were subsequently separated into accurate (n = 15) and inaccurate (n = 16) groups, with lower-body lean mass assessed using whole body DXA scans, and lower-body strength assessed using an isometric protocol. Accurate kickers demonstrated significantly higher relative lean mass (~8% to 16%; p = 0. 001 to 0.004) and significantly lower relative fat mass (~21% to 40%; p = 0.001 to 0.024) than inaccurate kickers. Accurate kickers did not contain any significant difference in lean mass or unilateral strength between lower limbs. Inaccurate kickers displayed significant asymmetry in lean mass (~3%; p ≤ 0.003), producing significant imbalances in strength (~8%; p ≤ 0.002) highlighting a deficiency in their support leg. Greater relative strength and improved lower limb symmetry in strength and muscularity could increase the capacity of an athlete to be technically proficient in favour of greater accuracy. Key PointsStrength deficits in the support leg may lead to inaccurate kicking outcomes.An asymmetry of 3% in lean mass generated an 8% imbalance in leg strength.Greater levels of relative lower-body strength and muscle mass are associated with improved kicking accuracy performance.

  8. Influence of silica fume on the strength of high strength concrete

    International Nuclear Information System (INIS)

    Akram, T.; Memon, S.A.; Khan, S.A.

    2007-01-01

    HSC (High Strength Concrete) does not become evident by a sudden change in the behavior of 'ordinary strength' concrete. There is a gradual effect that becomes more noticeable when the strength level exceeds about 40-45 MPa. There cannot be a precise level of strength which defines this change in effect. The effects are on strength and workability, requiring us to take into account in our mix proportioning, the ramifications of fineness of cement on workability and of type of aggregate and aggregate/cement ratio on strength. In fact, the selection of materials becomes more critical as the concrete strength increases and that if very high strength is required (100 MPa and higher), relatively few materials may be suitable. An experimental investigation is carried out to evaluate the feasibility of producing HSC using locally available materials and to study the influence of silica fume on the strength of HSC. The main variables in this research is amount of silica fume. The parameters that are kept constant are the amount of cement equal to 580 kg/m3, dosage of HRWRA (High Range Water Reducing Admictures) equal to 4 % by weight of cementitious materials and the ratio of fine aggregate to coarse aggregate (1:2.3). Test results revealed that it is feasible to produce HSC using locally available materials. The optimum percentage of silica fume was found to be 15 % by weight of cement. (author)

  9. Using Strengthsfinder to Identify Relationships between Marketing Graduate Strengths and Career Outcomes

    Science.gov (United States)

    Tomkovick, Chuck; Swanson, Scott

    2014-01-01

    The present study seeks to better understand how marketing graduates' strengths, and utilization of those strengths in the workplace, may be associated with a variety of academic and career outcomes. Respondents completed two different questionnaires. Findings suggest that marketing graduates whose strengths are not being utilized with their work…

  10. Influence of multiaxial preloading on the strength of concrete

    International Nuclear Information System (INIS)

    Linse, D.

    1975-01-01

    In a preliminary study about the influence of the loading direction discs of 20/20/5 cm were loaded at different stress-rates in one direction, then unloaded and loaded up to failure again. Two series of each about 15 specimens were tested: the first series was reloaded in the same direction as it was loaded before. If the preloading was not greater than about 90% of the original short-term uniaxial strength βsub(p), one could achieve in the second loading a higher strength than the strength βsub(p). The second series was reloaded normal to the direction of preloading. By an other series of about 50 specimens the influence of triaxial preloading on the uniaxial strength of concrete was tested. Cubes of 10cm were loaded by brush bearing platens up to a stress which was maximally three times higher than the uniaxial short-term strength βsub(p), then unloaded and tested again under uniaxial compression. The achieved ultimate strength of the cubes at the second loading was obviously dependent upon the stress-state and the stress-rate of the preloading. Multiaxial preloading which is far below the ultimate multiaxial strength can considerably defect the remaining strength of concrete. The decrease in strength was defined by the reduction of the uniaxial strength. It can be assumed that the remaining multiaxial strength is reduced at least to the same rate. Further tests are planned

  11. Strengths, Risk Factors, and Resilient Outcomes in Adolescents With Type 1 Diabetes

    DEFF Research Database (Denmark)

    Hilliard, Marisa E; Hagger, Virginia; Hendrieckx, Christel

    2017-01-01

    OBJECTIVE: Despite the challenges of living with type 1 diabetes, many adolescents achieve "resilient outcomes": high engagement in self-management behaviors such as self-monitoring of blood glucose (SMBG), good quality of life (QOL), and within-target glycemic outcomes (HbA1c). Adaptive diabetes...... factors. RESEARCH DESIGN AND METHODS: A total of 471 Australian adolescents with type 1 diabetes (mean age 15.7 ± 1.9 years; diabetes duration 6.9 ± 4.2 years; 62% female; 53% using insulin pumps) completed a national cross-sectional survey about their diabetes-related strengths, risk factors (depressive....../anxiety symptoms, family conflict), and resilient outcomes (SMBG frequency, general QOL, HbA1c). RESULTS: Greater diabetes strengths were significantly related to resilient outcomes: more frequent SMBG (r = 0.39), lower HbA1c (r = -0.31), and higher general QOL (r = 0.50), as well as to lower risks: fewer...

  12. Joint-Angle Specific Strength Adaptations Influence Improvements in Power in Highly Trained Athletes

    Directory of Open Access Journals (Sweden)

    Rhea Matthew R.

    2016-03-01

    Full Text Available Purpose. The purpose of this study was to examine the influence of training at different ranges of motion during the squat exercise on joint-angle specific strength adaptations. Methods. Twenty eight men were randomly assigned to one of three training groups, differing only in the depth of squats (quarter squat, half squat, and full squat performed in 16-week training intervention. Strength measures were conducted in the back squat pre-, mid-, and post-training at all three depths. Vertical jump and 40-yard sprint time were also measured. Results. Individuals in the quarter and full squat training groups improved significantly more at the specific depth at which they trained when compared to the other two groups (p < 0.05. Jump height and sprint speed improved in all groups (p < 0.05; however, the quarter squat had the greatest transfer to both outcomes. Conclusions. Consistently including quarter squats in workouts aimed at maximizing speed and jumping power can result in greater improvements.

  13. Influence of initial imperfections on ultimate strength of spherical shells

    Directory of Open Access Journals (Sweden)

    Chang-Li Yu

    2017-09-01

    Full Text Available Comprehensive consideration regarding influence mechanisms of initial imperfections on ultimate strength of spherical shells is taken to satisfy requirement of deep-sea structural design. The feasibility of innovative numerical procedure that combines welding simulation and non-linear buckling analysis is verified by a good agreement to experimental and theoretical results. Spherical shells with a series of wall thicknesses to radius ratios are studied. Residual stress and deformations from welding process are investigated separately. Variant influence mechanisms are discovered. Residual stress is demonstrated to be influential to stress field and buckling behavior but not to the ultimate strength. Deformations are proved to have a significant impact on ultimate strength. When central angles are less than critical value, concave magnitudes reduce ultimate strengths linearly. However, deformations with central angles above critical value are of much greater harm. Less imperfection susceptibility is found in spherical shells with larger wall thicknesses to radius ratios.

  14. The Influence of Forward and Backward Associative Strength on False Memories for Encoding Context

    Science.gov (United States)

    Arndt, Jason

    2016-01-01

    Two experiments examined the effects of Forward Associative Strength (FAS) and Backward Associative Strength (FAS) on false recollection of unstudied lure items. Themes were constructed such that four associates were strongly related to a lure item in terms of FAS or BAS and four associates were weakly related to a lure item in terms of FAS or BAS. Further, when FAS was manipulated, BAS was controlled across strong and weak associates, while FAS was controlled across strong and weak associates when BAS was manipulated. Strong associates were presented in one font while weak associates were presented in a second font. At test, lure items were disproportionately attributed to the source used to present lures’ strong associates compared to lures’ weak associates, both when BAS was manipulated and when FAS was manipulated. This outcome demonstrates that both BAS and FAS influence lure item false recollection, which favors global-matching models’ explanation of false recollection over the explanation offered by spreading-activation theories. PMID:25312499

  15. Malnutrition is prevalent in patients with cardiorenal syndrome and negatively influences clinical outcome.

    Science.gov (United States)

    Gigante, A; Rosato, E; Barbano, B; Di Mario, F; Di Lazzaro-Giraldi, G; Gasperini, M L; Pofi, R; Laviano, A

    2018-01-01

    Cardiorenal syndrome (CRS) describes the concurrent failure of cardiac and renal function, each influencing the other. Malnutrition and cachexia frequently develop in patients with heart failure or kidney failure. However, no information is currently available on the prevalence of malnutrition in CRS patients. We studied CRS patients admitted to an internal medicine ward during a 5-month period and evaluated their clinical characteristics and nutritional status. Malnutrition risk was assessed by using the validated screening tool NRS-2002 whilst body composition was assessed by bioimpedance analysis and muscle function was measured by handgrip (HG) strength. Cardiac mass was also recorded. Length of stay, hospital readmission and 6-month mortality were registered. During the study period, 22 CRS patients were studied. Twenty patients were diagnosed with either CRS type 1 or CRS type 5. In CRS patients, fat-free mass showed a trend toward representing a protective factor for 6-month mortality (OR=0.904; p=0.06). Also, fat-free mass correlated with HG strength and cardiac ejection fraction. Malnutrition risk was diagnosed in 45% of the patients, whereas 8 patients met the definition of cachexia. Even without statistical significance, CRS patients with malnutrition had lower BMI (Body Mass Index) (p=0.038) and fat-free mass (p= n.s.). However, CRS malnutrition was associated to higher 6-month mortality (p= 0.05), and appears to negatively influence the outcome in CRS (OR= 9; p= 0.06). Our results show that malnutrition is prevalent in CRS patients and influences the clinical outcome. The assessment of nutritional status, and particularly body composition, should be implemented in daily practice of patients with CRS.

  16. Influence of Binding Rates on Strength Properties of Moulding Sands with the GEOPOL Binder

    Directory of Open Access Journals (Sweden)

    Holtzer M.

    2014-03-01

    Full Text Available The results of investigations of moulding sands with an inorganic binder called GEOPOL, developed by the SAND TEAM Company are presented in the paper. Hardeners of various hardening rates are used for moulding sands with this binder. The main aim of investigations was determination of the influence of the hardening rate of moulding sands with the GEOPOL binder on technological properties of these sands (bending strength, tensile strength, permeability and grindability. In addition, the final strength of moulding sands of the selected compositions was determined by two methods: by splitting strength and shear strength measurements. No essential influence of the hardening rate on such parameters as: permeability, grindability and final strength was found. However, the sand in which the slowest hardener (SA 72 were used, after 1 hour of holding, had the tensile and bending strength practically zero. Thus, the time needed for taking to pieces the mould made of such moulding sand will be 1.5 - 2 hours.

  17. The Influence of Diatomite on the Strength and Microstructure of Portland Cement

    Directory of Open Access Journals (Sweden)

    Liu Jun

    2016-01-01

    Full Text Available To study the influence of the types and mixing amount of diatomite on the Portland cement, we prepared the cement specimen doped with the calcined first-grade, first-grade and second-grade diatomite ,tested the 3d, 7d, 14d compressive strength, and studied and discussed phase, structure and morphology of diatomite in the binary system by the method of XRD, SEM . Experimental results show that with the addition of diatomite, the strength of cement paste increase; the optimal contents of calcined first-grade ,first-grade and second-grade diatomite in Portland cement are 5%,Compared to the blank group, the strength of specimen can be increased by 54.6%, 15.4% and 10.2%, respectively; At the same time ,the 7d microscopic hydration of different diatomite particles were analyzed through the experiment , and the shell of calcined diatomite particles were better hydrated than that of first-grade and second-grade diatomite particles. The results indicate that the diatomite can improve the strength of cement paste, the hydration of different diatomite particles can influence the growth of cement paste strength.

  18. influence of molding water content on shear strength characteristic

    African Journals Online (AJOL)

    eobe

    INFLUENCE OF MOLDING WATER CONTENT ON SHEAR STRENGTH OF COMPACTED CEMENT KILN DUST, K. J. Osinub. K. J. Osinub. K. J. Osinubi, et al. Nigerian Journal of Technology,. Vol. 34, No. 2, April 2015 267 pavements or as waste containment materials. Therefore, recent studies have been geared towards.

  19. Influence of bottom ash of palm oil on compressive strength of concrete

    Science.gov (United States)

    Saputra, Andika Ade Indra; Basyaruddin, Laksono, Muhamad Hasby; Muntaha, Mohamad

    2017-11-01

    The technological development of concrete demands innovation regarding the alternative material as a part of the effort in improving quality and minimizing reliance on currently used raw materials such as bottom ash of palm oil. Bottom ash known as domestic waste stemming from palm oil cultivation in East Kalimantan contains silica. Like cement in texture and size, bottom ash can be mixed with concrete in which the silica in concrete could help increase the compressive strength of concrete. This research was conducted by comparing between normal concrete and concrete containing bottom ash as which the materials were apart of cement replacement. The bottom ash used in this research had to pass sieve size (#200). The composition tested in this research involved ratio between cement and bottom ash with the following percentages: 100%: 0%, 90%: 10%, 85%: 15% and 80%: 20%. Planned to be within the same amount of compressive strength (fc 25 MPa), the compressive strength of concrete was tested at the age of 7, 14, and 28 days. Research result shows that the addition of bottom ash to concrete influenced workability in concrete, but it did not significantly influence the compressive strength of concrete. Based on the result of compressive strength test, the optimal compressive strength was obtained from the mixture of 100% cement and 0% bottom ash.

  20. Influence of strength training intensity on subsequent recovery in elderly

    DEFF Research Database (Denmark)

    da Rosa Orssatto, Lucas Bet; de Moura, Bruno Monteiro; de Souza Bezerra, Ewertton

    2018-01-01

    Understanding the influence of strength training intensity on subsequent recovery in elderly is important to avoid reductions in physical function during the days following training. Twenty-two elderly were randomized in two groups: G70 (65.9 ± 4.8 years, n = 11) and G95 (66.9 ± 5.1, n = 11...... in elderly depending on the type of physical function and intensity of training. Higher intensity resulted in greater impairment. Exercise prescription in elderly should take this into account, e.g., by gradually increasing intensity during the first months of strength training. These results have relevance...... for elderly who have to be fit for work or other activities in the days following strength training....

  1. The influence of main bar corrosion on bond strength in selfcompacting concrete

    Science.gov (United States)

    Ayop, S. S.; Emhemed, A. N. K.; Jamaluddin, N.; Sadikin, A.

    2017-11-01

    The experimental study was conducted to determine the influence of main bar corrosion on bond strength in self-compacting concrete (SCC). A total 16 tension pullout tests specimens reinforced with 10 mm and 14 mm diameter bar were used for the bond strength test. The properties of SCC were determined from the slump flow, T50cm, V-funnel and L box test. Reinforcing bars in the concrete were submitted to impressed current to accelerate the corrosion of the bar. It was found that the relationship between bond strength and concrete strength in un-corroded specimens differed from that of corroded specimens set in high-strength concrete because of brittleness in the corroded specimens, which caused a sudden loss of bond strength. The results revealed that specimens of un-corroded and corroded showed a higher percentage of bond strength degradation during the pullout tests.

  2. The influence of cooling forearm/hand and gender on estimation of handgrip strength.

    Science.gov (United States)

    Cheng, Chih-Chan; Shih, Yuh-Chuan; Tsai, Yue-Jin; Chi, Chia-Fen

    2014-01-01

    Handgrip strength is essential in manual operations and activities of daily life, but the influence of forearm/hand skin temperature on estimation of handgrip strength is not well documented. Therefore, the present study intended to investigate the effect of local cooling of the forearm/hand on estimation of handgrip strength at various target force levels (TFLs, in percentage of MVC) for both genders. A cold pressor test was used to lower and maintain the hand skin temperature at 14°C for comparison with the uncooled condition. A total of 10 male and 10 female participants were recruited. The results indicated that females had greater absolute estimation deviations. In addition, both genders had greater absolute deviations in the middle range of TFLs. Cooling caused an underestimation of grip strength. Furthermore, a power function is recommended for establishing the relationship between actual and estimated handgrip force. Statement of relevance: Manipulation with grip strength is essential in daily life and the workplace, so it is important to understand the influence of lowering the forearm/hand skin temperature on grip-strength estimation. Females and the middle range of TFL had greater deviations. Cooling the forearm/hand tended to cause underestimation, and a power function is recommended for establishing the relationship between actual and estimated handgrip force. Practitioner Summary: It is important to understand the effect of lowering the forearm/hand skin temperature on grip-strength estimation. A cold pressor was used to cool the hand. The cooling caused underestimation, and a power function is recommended for establishing the relationship between actual and estimated handgrip force. Manipulation with grip strength is essential in daily life and the workplace, so it is important to understand the influence of lowering the forearm/hand skin temperature on grip-strength estimation. Females and the middle range of TFL had greater deviations. Cooling the

  3. Influence of cracks and pitting corrosion on residual ultimate strength of stiffened plates

    Directory of Open Access Journals (Sweden)

    ZHANG Jing

    2018-02-01

    Full Text Available [Objectives] Ships and offshore platforms serve in the harsh sea environment for a long time. Cracks and pitting corrosion will occur in such a structure and the damage will affect its ultimate strength.[Methods] To investigate the influence of cracks and pitting corrosion on ultimate bearing capacity, the ultimate strength of a structure under axial compression is studied by using a nonlinear finite element. The mesh size of a stiffened plate with cracks and pitting corrosion is first discussed. Then the influence of the relative positions of cracks and pitting corrosion, number of corrosion points and crack length impact on the residual ultimate strength of damaged stiffened plates is discussed via a series of calculations.[Results] The results indicate that the increase in crack length and pitting corrosion significantly decreases the ultimate strength of a stiffened plate. [Conclusions] This provides a useful reference for designing and maintaining ships and offshore structures in their life cycles.

  4. Shear bond strength of metallic brackets: influence of saliva contamination

    Directory of Open Access Journals (Sweden)

    Luciana Borges Retamoso

    2009-06-01

    Full Text Available OBJECTIVE: To evaluate the influence of saliva contamination on shear bond strength and the bond failure pattern of 3 adhesive systems (Transbond XT, AdheSE and Xeno III on orthodontic metallic brackets bonded to human enamel. MATERIAL AND METHODS: Seventy-two permanent human molars were cut longitudinally in a mesiodistal direction, producing seventy-two specimens randomly divided into six groups. Each system was tested under 2 different enamel conditions: no contamination and contaminated with saliva. In T, A and X groups, the adhesive systems were applied to the enamel surface in accordance with manufacturer's instructions. In TS, AS and XS groups, saliva was applied to enamel surface followed by adhesive system application. The samples were stored in distilled water at 37ºC for 24 h, and then tested for shear bond strength in a universal testing machine (Emic, DL 2000 running at a crosshead speed of 1 mm/min. After bond failure, the enamel surfaces were observed under an optical microscope at 40x magnification. RESULTS: The control and contaminated groups showed no significant difference in shear bond strength for the same adhesive system. However, shear bond strength of T group (17.03±4.91 was significantly higher than that of AS (8.58±1.73 and XS (10.39±4.06 groups (p<0.05. Regarding the bond failure pattern, TS group had significantly higher scores of no adhesive remaining on the tooth in the bonding area than other groups considering the adhesive remnant index (ARI used to evaluate the amount of adhesive left on the enamel. CONCLUSIONS: Saliva contamination showed little influence on the 24-h shear bond strength of orthodontic brackets.

  5. Influence of manufacturing parameters on the strength of PLA parts using Layered Manufacturing technique: A statistical approach

    Science.gov (United States)

    Jaya Christiyan, K. G.; Chandrasekhar, U.; Mathivanan, N. Rajesh; Venkateswarlu, K.

    2018-02-01

    A 3D printing was successfully used to fabricate samples of Polylactic Acid (PLA). Processing parameters such as Lay-up speed, Lay-up thickness, and printing nozzle were varied. All samples were tested for flexural strength using three point load test. A statistical mathematical model was developed to correlate the processing parameters with flexural strength. The result clearly demonstrated that the lay-up thickness and nozzle diameter influenced flexural strength significantly, whereas lay-up speed hardly influenced the flexural strength.

  6. Responsiveness of performance-based outcome measures for mobility, balance, muscle strength and manual dexterity in adults with myotonic dystrophy type 1.

    Science.gov (United States)

    Kierkegaard, Marie; Petitclerc, Émilie; Hébert, Luc J; Mathieu, Jean; Gagnon, Cynthia

    2018-02-28

    To assess changes and responsiveness in outcome measures of mobility, balance, muscle strength and manual dexterity in adults with myotonic dystrophy type 1. A 9-year longitudinal study conducted with 113 patients. The responsiveness of the Timed Up and Go test, Berg Balance Scale, quantitative muscle testing, grip and pinch-grip strength, and Purdue Pegboard Test was assessed using criterion and construct approaches. Patient-reported perceived changes (worse/stable) in balance, walking, lower-limb weakness, stair-climbing and hand weakness were used as criteria. Predefined hypotheses about expected area under the receiver operating characteristic curves (criterion approach) and correlations between relative changes (construct approach) were explored. The direction and magnitude of median changes in outcome measures corresponded with patient-reported changes. Median changes in the Timed Up and Go test, grip strength, pinch-grip strength and Purdue Pegboard Test did not, in general, exceed known measurement errors. Most criterion (72%) and construct (70%) approach hypotheses were supported. Promising responsiveness was found for outcome measures of mobility, balance and muscle strength. Grip strength and manual dexterity measures showed poorer responsiveness. The performance-based outcome measures captured changes over the 9-year period and responsiveness was promising. Knowledge of measurement errors is needed to interpret the meaning of these longitudinal changes.

  7. Influence of superplasticizer on microstructure of a 40 MPa strength concrete

    International Nuclear Information System (INIS)

    Teixeira, Sandra M.F.; Menezes, Raquel Maria R.O.; Figueiredo, Roberto B.; Aguilar, Maria Teresa P.; Franca, Fabricio Carlos; Bezerra, Augusto Cesar da S.

    2016-01-01

    The self compacting concrete has high fluidity and deformability. Studies analyze its performance through compressive strength, mortar content and / or water cement factor, which does not allow the evaluation of superplasticante influence the microstructure of these concretes. In this work, we evaluated the influence of superplasticizer comparing the phases present in a self-compacting concrete 40 MPa and at a same conventional compressive strength, same water / cement and mortar content. Therefore, scanning techniques were employed by electron microscope low vacuum using backscattered electrons and thermal analysis. The observed results show no significant differences in the microstructure of the two composites, ie the superplasticizer does not alter the microstructure of the self-compacting concrete. However, thermal analysis indicates that the present self-compacting concrete greater calcium hydroxide content which may suggest a lower content of such dry cement concrete. (author)

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

    Science.gov (United States)

    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.

  9. The Influence of Creatine Monohydrate on Strength and Endurance After Doing Physical Exercise With Maximum Intensity

    Directory of Open Access Journals (Sweden)

    Asrofi Shicas Nabawi

    2017-11-01

    Full Text Available The purpose of this study was: (1 to analyze the effect of creatine monohydrate to give strength after doing physical exercise with maximum intensity, towards endurance after doing physical exercise with maximum intensity, (2 to analyze the effect of non creatine monohydrate to give strength after doing physical exercise with maximum intensity, towards endurance after doing physical exercise with maximum intensity, (3 to analyze the results of the difference by administering creatine and non creatine on strength and endurance after exercise with maximum intensity. This type of research used in this research was quantitative with quasi experimental research methods. The design of this study was using pretest and posttest control group design, and data analysis was using a paired sample t-test. The process of data collection was done with the test leg muscle strength using a strength test with back and leg dynamometer, sit ups test with 1 minute sit ups, push ups test with push ups and 30 seconds with a VO2max test cosmed quart CPET during the pretest and posttest. Furthermore, the data were analyzed using SPSS 22.0 series. The results showed: (1 There was the influence of creatine administration against the strength after doing exercise with maximum intensity; (2 There was the influence of creatine administration against the group endurance after doing exercise with maximum intensity; (3 There was the influence of non creatine against the force after exercise maximum intensity; (4 There was the influence of non creatine against the group after endurance exercise maximum intensity; (5 The significant difference with the provision of non creatine and creatine from creatine group difference delta at higher against the increased strength and endurance after exercise maximum intensity. Based on the above analysis, it can be concluded that the increased strength and durability for each of the groups after being given a workout.

  10. The influence of stretching on tensile strength and solubility of poly(vinyl alcohol) fibres

    NARCIS (Netherlands)

    Heikens, D.; Bleijenberg, A.C.A.M.; Hoppenbrouwers, J.J.M.; Barentsen, W.M.

    1971-01-01

    The strength of wet-spun poly(vinyl alcohol) (pva) fibres is given as function of bath-stretching, wet-stretching and hot-stretching. In the two equations derived for strength of wet-stretching and hot-stretching the complex influence of the bath-stretching and hot-stretching is demonstrated. The

  11. Change in the level of strength and endurance development of 5-6 grades pupils under cheerleading exercises influence

    Directory of Open Access Journals (Sweden)

    Tetyana Bala

    2015-06-01

    Full Text Available Purpose: determine the degree of change in the level of strength and endurance development of 5-6 grades pupils under cheerleading exercises influence. Material and Methods: theoretical analysis and generalization of scientific and methodical literature, pedagogical testing, pedagogical experiment and mathematical statistics methods. Results: parameters of strength and endurance development level are presented with their degree of change under cheerleading exercises influence for 5-6 grades pupils of secondary school. Conclusions: cheerleading exercises usage has positive influence on demonstrated strength and endurance degree of secondary school children by all investigated parameters.

  12. Influence of laser cutting on the fatigue limit of two high strength steels

    International Nuclear Information System (INIS)

    Mateo, Antonio; Fargas, Gemma; Calvo, Jessica; Roa, Joan Josep

    2015-01-01

    Laser cutting is widely used in the metal industry, particularly when components of high strength steel sheets are produced. However, the roughness of cut edges produced by laser differs from that obtained by other methods, such as mechanical blanking, and this fact influences the fatigue performance. In the present investigation, specimens of two grades of high strength austenitic steels, i.e. AISI 301LN and TWIP17Mn, were cut by laser and tested in the high cycle fatigue regime to determine their corresponding fatigue limits. A series of fatigue specimens were tested without polishing and other series after a careful polishing of the cut edges, in order to assess the influence of the cut edges condition. Results indicate a significant influence of the edge roughness, more distinctive for AISI 301LN than for TWIP steel.

  13. Influence of laser cutting on the fatigue limit of two high strength steels

    Energy Technology Data Exchange (ETDEWEB)

    Mateo, Antonio; Fargas, Gemma; Calvo, Jessica; Roa, Joan Josep [Univ. Politecnica de Catalunya, Barcelona (Spain). Dept. of Materials Science and Metallurgical Engineering

    2015-02-01

    Laser cutting is widely used in the metal industry, particularly when components of high strength steel sheets are produced. However, the roughness of cut edges produced by laser differs from that obtained by other methods, such as mechanical blanking, and this fact influences the fatigue performance. In the present investigation, specimens of two grades of high strength austenitic steels, i.e. AISI 301LN and TWIP17Mn, were cut by laser and tested in the high cycle fatigue regime to determine their corresponding fatigue limits. A series of fatigue specimens were tested without polishing and other series after a careful polishing of the cut edges, in order to assess the influence of the cut edges condition. Results indicate a significant influence of the edge roughness, more distinctive for AISI 301LN than for TWIP steel.

  14. The influence of tongue strength on oral viscosity discrimination acuity.

    Science.gov (United States)

    Steele, Catriona M

    2018-06-01

    The ability to generate tongue pressures is widely considered to be critical for liquid bolus propulsion in swallowing. It has been proposed that the application of tongue pressure may also serve the function of collecting sensory information regarding bolus viscosity (resistance to flow). In this study, we explored the impact of age-related reductions in tongue strength on oral viscosity discrimination acuity. The experiment employed a triangle test discrimination protocol with an array of xanthan-gum thickened liquids in the mildly to moderately thick consistency range. A sample of 346 healthy volunteers was recruited, with age ranging from 12 to 86 (164 men, 182 women). On average, participants were able to detect a 0.29-fold increase in xanthan-gum concentration, corresponding to a 0.5-fold increase in viscosity at 50/s. Despite having significantly reduced tongue strength on maximum isometric tongue-palate pressure tasks, and regardless of sex, older participants in this study showed no reductions in viscosity discrimination acuity. In this article, the relationship between tongue strength and the ability to discriminate small differences in liquid viscosity during oral processing is explored. Given that tongue strength declines with age in healthy adults and is also reduced in individuals with dysphagia, it is interesting to determine whether reduced tongue strength might contribute to difficulties in evaluating liquid viscosity during the oral stage of swallowing. Using an array of mildly to moderately thick xanthan-gum thickened liquids, this experiment failed to find any evidence that reductions in tongue strength influence oral viscosity discrimination acuity. © 2017 Wiley Periodicals, Inc.

  15. On the influence of load variations on lifetime and strength of wood

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    2006-01-01

    To days recommendations for probability and reliability analysis of wood structures do not fully recognize the influence of wood microstructure and creep on the mechanical behavior of wood. As a consequence, certain important features in wood design cannot be considered properly. Ignoring the bas...... history on recycle-strength (residual strength). It is demonstrated in this paper, how the problems just mentioned can be solved from respecting wood as a damaged viscoelastic material, meaning that wood is a cracked (damaged) material with creep....

  16. The Influence of Diatomite on the Strength and Microstructure of Portland Cement

    OpenAIRE

    Liu Jun; Shao Peng; Wang Shihao

    2016-01-01

    To study the influence of the types and mixing amount of diatomite on the Portland cement, we prepared the cement specimen doped with the calcined first-grade, first-grade and second-grade diatomite ,tested the 3d, 7d, 14d compressive strength, and studied and discussed phase, structure and morphology of diatomite in the binary system by the method of XRD, SEM . Experimental results show that with the addition of diatomite, the strength of cement paste increase; the optimal contents of calcin...

  17. Influence of refraction index strength on the light propagation in dielectrics material with periodic refraction index

    International Nuclear Information System (INIS)

    Hidayat, Arif; Latifah, Eny; Kurniati, Diana; Wisodo, Hari

    2016-01-01

    This study investigated the influence of refraction index strength on the light propagation in refraction index-varied dielectric material. This dielectric material served as photonic lattice. The behavior of light propagation influenced by variation of refraction index in photonic lattice was investigated. Modes of the guiding light were determined numerically using squared-operator iteration method. It was found that the greater the strength of refraction index, the smaller the guiding modes.

  18. The Role of Explicit Need Strength for Emotions during Learning

    Science.gov (United States)

    Flunger, Barbara; Pretsch, Johanna; Schmitt, Manfred; Ludwig, Peter

    2013-01-01

    According to self-determination theory, the satisfaction of the basic needs for autonomy, competence, and relatedness influences achievement emotions and situational interest. The present study investigated whether domain-specific explicit need strength moderated the impact of need satisfaction/dissatisfaction on the outcomes achievement emotions…

  19. The Gait Deviation Index Is Associated with Hip Muscle Strength and Patient-Reported Outcome in Patients with Severe Hip Osteoarthritis

    DEFF Research Database (Denmark)

    Rosenlund, Signe; Holsgaard-Larsen, Anders; Overgaard, Søren

    2016-01-01

    ) and with severe primary hip osteoarthritis underwent 3-dimensional gait analysis. Mean Gait Deviation Index, pain after walking and maximal isometric hip muscle strength (flexor, extensor, and abductor) were recorded. All patients completed the 'Physical Function Short-form of the Hip disability...... was to investigate associations between Gait Deviation Index as a measure of gait 'quality' and hip muscle strength and between Gait Deviation Index and patient-reported outcomes in patients with primary hip osteoarthritis. METHOD: Forty-seven patients (34 males), aged 61.1 ± 6.7 years, with BMI 27.3 ± 3.4 (kg/m2...... and Osteoarthritis Outcome Score (HOOS-Physical Function) and the Hip disability and Osteoarthritis Outcome Score subscales for pain (HOOS-Pain) and quality-of-life (HOOS-QOL). RESULTS: Mean Gait Deviation Index was positively associated with hip abduction strength (pstrength (p = 0...

  20. Influence of adhesion promoters and curing-light sources on the shear bond strength of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Claudia Tavares Machado

    2012-01-01

    Conclusions: The conventional orthodontic adhesive presented higher bond strength than the nanofilled composite, although both materials interacted similarly to the teeth. The curing-light devices tested did not influence on bond strength of orthodontic brackets.

  1. Influence of microstructure of high-strength low-alloy steels on their weldability

    International Nuclear Information System (INIS)

    Cwiek, J.; Labanowski, J.

    2003-01-01

    Microstructure of steel before welding has influence on the steel's susceptibility to cold cracking because it influences hardenability and maximum hardness of heat affected zone (HAZ). Two high-strength low-alloy (HSLA) steel grades 18G2AV and 14HNMBCu, in various heat treatment conditions, were subjected to simulated welding thermal cycles. It was revealed that maximum HAZ hardness is influenced by microstructure presented before thermal cycle was applied. The higher HAZ hardness was observed for quenched and tempered condition, comparing to full annealed and overheated conditions. (author)

  2. 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

  3. Does gender influence outcomes in critically ill patients?

    OpenAIRE

    Angele, Martin K; Pratschke, Sebastian; Chaudry, Irshad H

    2012-01-01

    Investigators continue to debate whether gender plays any role in patient outcome following injury/critical illness. We submit that age and hormonal milieu at the time of injury, rather than gender, are the critical factors influencing patient outcome under those conditions.

  4. Influence of MSD crack pattern on the residual strength of flat stiffened sheets

    Science.gov (United States)

    Nilsson, K.-F.

    A parameter study of the residual strength for a multiple site damaged (MSD) stiffened sheet is presented. The analysis is based on an elastic-plastic fracture analysis using the yield-strip model for interaction between a lead crack and the smaller MSD cracks. Two crack growth criteria, one with a pronounced crack growth resistance and one with no crack growth resistance and five different MSD crack patterns, are analysed for different sizes of the lead crack and the smaller MSD cracks. The analysis indicates that the residual strength reduction depends on all these parameters and that MSD may totally erode the crack arrest capability of a tear strap. Another important outcome is that for certain combinations also very small MSD cracks may induce a significant residual strength reduction.

  5. The influence of annealing temperature on the strength of TRISO coated particles

    International Nuclear Information System (INIS)

    Rooyen, I.J. van; Neethling, J.H.; Rooyen, P.M. van

    2010-01-01

    The integrity of the Pebble Bed Modular Reactor (PBMR) fuel, and specifically the SiC layer system of the Tristructural Isotropic (TRISO) coated particle (CP), namely inner pyrolytic carbon, silicon carbide and outer pyrolytic carbon (I-PyC-SiC-O-PyC), determines the containment of fission products. The PBMR fuel consists of TRISO coated particles (CPs) embedded in a graphite matrix. One of the characterization techniques investigated by PBMR is the determination of strength of CPs. It is a well known metallurgical fact that temperature, amongst many other parameters, may influence the strength of a material. A recently developed method for measuring the strength of the TRISO coated particles was used and is briefly described in this article. The advantages of this method are demonstrated by the comparison of strength measurements of five experimental PBMR CP batches as a function of annealing temperature. Significant modification of strength after annealing was measured with increased temperature within the range 1000-2100 o C. The interesting feature of decreasing standard deviation of the strength with increasing temperature will also be discussed with a possible explanation. A significant difference in coated particle strength is also demonstrated for two CP batches with layer thickness on the extremities of the SiC layer thickness specification. The effect of long duration annealing on these strength values will also be demonstrated by comparing results from 1 h to 100 h annealing periods of coated particles at a temperature of 1600 o C.

  6. Shear bond strength of one-step self-etch adhesives: pH influence

    Science.gov (United States)

    Poggio, Claudio; Beltrami, Riccardo; Scribante, Andrea; Colombo, Marco; Chiesa, Marco

    2015-01-01

    Background: The aim of this study was to compare the shear bond strength of four one-step self-etch adhesives with different pH values to enamel and dentin. Materials and Methods: In this in vitro study, 200 bovine permanent mandibular incisors were used. Four one-step self-etch adhesives with different pH values were tested both on enamel and on dentin: Adper™ Easy Bond Self-Etch Adhesive (pH = 0.8-1), Futurabond NR (pH=2), G-aenial Bond (pH = 1.5), Clearfil S3 Bond (pH = 2.7). After adhesive systems application, a nanohybrid composite resin was inserted into the bonded surface. The specimens were placed in a universal testing machine. The shear bond strength was performed at a cross-head speed of 1 mm/min until the sample rupture. The shear bond strength values (MPa) of the different groups were compared with analysis of variance after that Kolmogorov and Smirnov tests were applied to assess normality of distributions. P enamel shear bond strength, the highest shear bond strength values were reported with Futurabond NR (P adhesive systems showed lower shear bond strength values with significant differences between them (P 0.05). Conclusion: The pH values of adhesive systems did not influence significantly their shear bond strength to enamel or dentin. PMID:26005459

  7. Tensile strength of solution-spun, ultradrawn ultrahigh-molecular-weight polyethylene fibers. 1. Influence of fiber diameter

    OpenAIRE

    Bastiaansen, C.W.M.

    1992-01-01

    The influence of fiber diam. on the tensile strength of soln.-spun, ultradrawn, ultrahigh-mol.-wt. polyethylene (UHMWPE, mol. wt. >103 kg/mol) fibers was studied. Fibers with a wide range of diams. were produced by varying the polymer concn. in soln. and by applying a drawdown to the fibers. The tensile strength of drawn fibers was compared at a const. Young's modulus in order to eliminate the influence of morphol. parameters, such as degree of chain orientation and extension, on the fracture...

  8. Influence of surface modified basalt fiber on strength of cinder lightweight aggregate concrete

    Science.gov (United States)

    Xiao, Liguang; Li, Jiheng; Liu, Qingshun

    2017-12-01

    In order to improve the bonding and bridging effect between volcanic slag lightweight aggregate concrete cement and basalt fiber, The basalt fiber was subjected to etching and roughening treatment by NaOH solution, and the surface of the basalt fiber was treated with a mixture of sodium silicate and micro-silica powder. The influence of modified basalt fiber on the strength of volcanic slag lightweight aggregate concrete was systematically studied. The experimental results show that the modified basalt fiber volcanic slag lightweight aggregate concrete has a flexural strength increased by 47%, the compressive strength is improved by 16% and the toughness is increased by 27% compared with that of the non-fiber.

  9. The influence of annealing temperature on the strength of TRISO coated particles

    Energy Technology Data Exchange (ETDEWEB)

    Rooyen, I.J. van, E-mail: Isabel.vanrooyen@pbmr.co.z [Pebble Bed Modular Reactor (Pty) Ltd., 1279 Mike Crawford Avenue, Centurion (South Africa); Department of Physics, Nelson Mandela Metropolitan University, Port Elizabeth (South Africa); Neethling, J.H. [Department of Physics, Nelson Mandela Metropolitan University, Port Elizabeth (South Africa); Rooyen, P.M. van [Pebble Bed Modular Reactor (Pty) Ltd., 1279 Mike Crawford Avenue, Centurion (South Africa)

    2010-07-31

    The integrity of the Pebble Bed Modular Reactor (PBMR) fuel, and specifically the SiC layer system of the Tristructural Isotropic (TRISO) coated particle (CP), namely inner pyrolytic carbon, silicon carbide and outer pyrolytic carbon (I-PyC-SiC-O-PyC), determines the containment of fission products. The PBMR fuel consists of TRISO coated particles (CPs) embedded in a graphite matrix. One of the characterization techniques investigated by PBMR is the determination of strength of CPs. It is a well known metallurgical fact that temperature, amongst many other parameters, may influence the strength of a material. A recently developed method for measuring the strength of the TRISO coated particles was used and is briefly described in this article. The advantages of this method are demonstrated by the comparison of strength measurements of five experimental PBMR CP batches as a function of annealing temperature. Significant modification of strength after annealing was measured with increased temperature within the range 1000-2100 {sup o}C. The interesting feature of decreasing standard deviation of the strength with increasing temperature will also be discussed with a possible explanation. A significant difference in coated particle strength is also demonstrated for two CP batches with layer thickness on the extremities of the SiC layer thickness specification. The effect of long duration annealing on these strength values will also be demonstrated by comparing results from 1 h to 100 h annealing periods of coated particles at a temperature of 1600 {sup o}C.

  10. Baseline strength can influence the ability of salivary free testosterone to predict squat and sprinting performance.

    Science.gov (United States)

    Crewther, Blair T; Cook, Christian J; Gaviglio, Chris M; Kilduff, Liam P; Drawer, Scott

    2012-01-01

    The objective of this study was to determine if salivary free testosterone can predict an athlete's performance during back squats and sprints over time and the influence baseline strength on this relationship. Ten weight-trained male athletes were divided into 2 groups based on their 1 repetition maximum (1RM) squats, good squatters (1RM > 2.0 × body weight, n = 5) and average squatters (1RM squat 1RM and 10-m sprint times on 10 separate occasions over a 40-day period. A saliva sample was collected before testing and assayed for free testosterone and cortisol. The pooled testosterone correlations were strong and significant in the good squatters (r = 0.92 for squats, r = -0.87 for sprints, p squats, r = -0.18 for sprints). Cortisol showed no significant correlations with 1RM squat and 10-m sprint performance, and no differences were identified between the 2 squatting groups. In summary, these results suggest that free testosterone is a strong individual predictor of squat and sprinting performance in individuals with relatively high strength levels but a poor predictor in less strong individuals. This information can assist coaches, trainers, and performance scientists working with stronger weight-trained athletes, for example, the preworkout measurement of free testosterone could indicate likely training outcomes or a readiness to train at a certain intensity level, especially if real-time measurements are made. Our results also highlight the need to separate group and individual hormonal data during the repeated testing of athletes with variable strength levels.

  11. 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

  12. Probabilistic concept to describe the influence of rate of loading on strength of concrete

    International Nuclear Information System (INIS)

    Mihashi, H.; Wittmann, F.H.

    1981-01-01

    Any reliability assessment of concrete structures is dependent on realistic assumptions on strength distribution. By means of experimental test series the most appropriate distribution function cannot be determined. In this contribution a theoretical concept to describe variability of strength of concrete will be presented. This approach is based on the characteristic composite structure. The structure of concrete is composed of aggregates and a binding agent i.e. porous hardened cement paste. Under formal conditions there are already big pores and cracks in the matrix as well as in the interface before a specimen is loaded. All structural defects can be assumed to be statistically distributed all over the specimen. If a load is applied cracks start to grow form the most critical structural defects. For a realistic estimation of the reliability of a secondary containment under impact loading conditions the influence of rate of loading on mean value and variability of strength is of major interest. The presented theory predicts that the mean strength increases with a power law as the rate of loading increases, while the coefficient of variation remains constant. A number of test series have been carried out to verify the theoretical concept. Different types of mortar (model concrete) and concrete have been included in the test program. Within the range of accuracy experimental results agree well with theoretical predictions. It can be concluded that the variability of macroscopic properties of concrete can be linked with the distribution of structural defects. Strength of concrete is best represented by a Weibull-type distribution function. The influence of rate of loading on strength can be experessed by means of a general rate process. (orig.)

  13. Influence of ionic strength on the viscosities and water loss of bentonite suspensions containing polymers

    Directory of Open Access Journals (Sweden)

    Luciana Viana Amorim

    2007-03-01

    Full Text Available A study was made of the influence of ionic strength (S on the apparent (AV and plastic (PV viscosities and water loss (WL of sodium bentonite suspension with polymers. Na-bentonite was dispersed in water (4.86% w/w of different ionic strengths (S = 0.0, 0.015, 0.030 and 0.045 M followed by the addition of polymer. Three polymer samples were studied, i.e., low viscosity carboxymethyl cellulose (CMC BV, polyanionic cellulose (PAC, and partially hydrolyzed polyacrylamide (HPAM. The results indicated that the presence of salts and increased salinity greatly influence the apparent and plastic viscosities and water loss of bentonite suspensions with polymer.

  14. The influence of aggregates type on W/C ratio on the strength and other properties of concrete

    Science.gov (United States)

    Malaiskiene, J.; Skripkiunas, G.; Vaiciene, M.; Karpova, E.

    2017-10-01

    The influence of different types of aggregates and W/C ratio on concrete properties is analysed. In order to achieve this aim, lightweight (with expanded clay aggregate) and normal concrete (with gravel aggregate) mixtures are prepared with different W/C ratios. Different W/C ratios are selected by reducing the amount of cement when the amount of water is constant. The following properties of concrete have been determined: density, compressive strength and water absorption. Additionally, the statistical data analysis is performed and influence of aggregate type and W/C ratio on concrete properties is determined. The empirical equations indicating dependence between concrete strength and W/C and strength of aggregate are obtained for normal concrete and light-weight concrete.

  15. The influence of various risk factors on the strength of pelvic floor muscle in women

    Directory of Open Access Journals (Sweden)

    Parezanović-Ilić Katarina

    2017-01-01

    Full Text Available Background/Aim. Damage of any element of pelvic floor leads to its functional damages, reflected in the occurrence of urinary incontinence, prolapse of pelvic organs, fecal incontinence and sexual dysfunction. Basic aim of our paper was to investigate the influence of various risk factors on pelvic floor muscle strength in women. Methods. The study included 90 female patients and examined how age, job, body weight and height, number of deliveries, sports activities, incontinence occurrence, previous prolapse-caused gynecological surgeries, other gynecological surgeries and other conservatively treated gynecological diseases influence the value of pelvic floor muscle strength. Pelvic floor muscle strength was measured using vaginal dynamometer. Results. Univariate regression analysis showed that parameters such as age, demanding job, body height, number of deliveries, sports activities, prolapse-caused gynecological surgeries, other gynecological surgeries and other gynecological diseases were in positive correlation with the values of pelvic floor muscle strength. In multivariate regression model, incontinence and gynecological operation of prolapse were singled out as independent risk factors. Conclusion. If risk factors that cause damage to pelvic floor muscle are known, it is possible to prevent the damages and improve the quality of women's life.

  16. Constraining is enabling? Exploring the influence of national context on civil society strength

    NARCIS (Netherlands)

    Kamstra, J.; Pelzer, B.J.; Elbers, W.J.; Ruben, R.

    2016-01-01

    This article analyses the influence of national context on civil society strength based on four key dimensions: level of democracy, political stability, rule of law and economic development. Whereas existing studies mainly focus on Western and post-communist countries, we explicitly include

  17. Constraining Is Enabling? Exploring the Influence of National Context on Civil Society Strength

    NARCIS (Netherlands)

    Kamstra, Jelmer; Pelzer, Ben; Elbers, Willem; Ruben, Ruerd

    2016-01-01

    This article analyses the influence of national context on civil society strength based on four key dimensions: level of democracy, political stability, rule of law and economic development. Whereas existing studies mainly focus on Western and post-communist countries, we explicitly include

  18. Investigating combined influence of petrology and technological parameters on strength of porous coke body

    Energy Technology Data Exchange (ETDEWEB)

    Dinel' t, V.M.; Shkoller, M.B.; Stankevich, A.S.; Korchuganova, G.S.

    1983-09-01

    The VUKhIN branch in Kuznetsk investigated effects of coal petrology and coking conditions on structural strength of coke in blast furnaces. Structural strength of coke produced from black coal from the Kuzbass as well as structural strength of coke partially gasified by carbon dioxide under conditions similar to those in blast furnaces was investigated. Fourteen samples of coal mixtures from the Kuzbass were used. Regression analysis was applied. Equations for forecasting coke properties on the basis of coal petrology and selected parameters characterizing coking were derived. Analyses showed that coke structural strength was decisively influenced by coefficients which characterized the average reflectivity of vitrinite in a coal mixture and its average density. After partial coke gasification by carbon dioxide effects of coefficients which characterized coal mixture nonhomogeneity (fluctuations of vitrinite reflectivity) and coal mixture density increased. Increasing coal density partially compensated negative effects of fluctuations of vitrinite reflectivity on coke structural strength. (10 refs.) (In Russian)

  19. Influence of alkali-silica reaction and crack orientation on the uniaxial compressive strength of concrete cores from slab bridges

    DEFF Research Database (Denmark)

    Antonio Barbosa, Ricardo; Gustenhoff Hansen, Søren; Hansen, Kurt Kielsgaard

    2018-01-01

    ASR-damaged flat slab bridges in service. Furthermore, the influence of the ASR-induced crack orientation on the compressive strength and the Young’s modulus is investigated. Uniaxial compression tests, visual observations, and thin section examinations were performed on more than 100 cores drilled...... from the three severely ASR-damaged flat slab bridges. It was found that the orientation of ASR-induced cracks has a significant influence on the uniaxial compressive strength and the stress-strain relationship of the tested cores. The compressive strength in a direction parallel to ASR cracks can...

  20. Influence of the Category Discharge Processing on Strength Properties of Piezocomposites

    International Nuclear Information System (INIS)

    Ramazanov, M. A.

    2006-01-01

    Piezoelectric, dielectric and physicomechanical properties of polymeric piezocomposites on piezoceramics basis are one of the major operational devices of applications. During their application in various devices for a long time can be exposed to various influences for a long time. Piezoelectric, dielectric and strength properties of polymeric piezocomposites strongly depend from the interphase phenomena, and also on charges saved up on border of the unit between components of a composition. Therefore creation the preliminary centers localization for charges in a composition is an actual problem for development effective polymeric piezocomposites. In the given work results of a research preliminary discharge processing's of powders of polymer on strength properties and dielectric characteristics of polymeric compositions on a basis polyvinilidenftorid (PVDF), high density polyethylene and piezoceramic from tetragonal structure are poisoned. Piezoceramic had structure plumbum-zirconate-titanate (PZT). Powders of polymer have been subjected to discharge processing in a quartz glass tube with a diameter 15 mm which walls with 1 mm. It is earthed, from one end and to other end it is connected with high-voltage electrode. Compositions in a volumetric ratio of 90+10 % have been obtained at temperature 435Κ under pressure 15ΜΠa. After creation reception of samples they were exposed electrothermopolarization. It is experimentally established, that after discharge processing powders of polymer depending on of processing duration electric and mechanical durability, and also an accrued charge on border of the unit of phases up to the certain value increases, and then decreases. Also it is shown, hat influence of category processing on strength and dielectric characteristics of a composition on the basis of polymer PVDF is more than , has on polyethylene basis. Changes piezoelectric, dielectric it is supposed, that, and strength properties to an extreme piezocomposite

  1. Systematic reviews: I. The correlation between laboratory tests on marginal quality and bond strength. II. The correlation between marginal quality and clinical outcome.

    Science.gov (United States)

    Heintze, Siegward D

    2007-01-01

    An accepted principle in restorative dentistry states that restorations should be placed with the best marginal quality possible to avoid postoperative sensitivity, marginal discoloration, and secondary caries. Different laboratory methods claim to predict the clinical performance of restorative materials, for example, tests of bond strength and microleakage and gap analysis. The purpose of this review was twofold: (1) find studies that correlated the results of bond strength tests with either microleakage or gap analysis for the same materials, and (2) find studies that correlated the results of microleakage and/or gaps with the clinical parameters for the same materials. Furthermore, influencing factors on the results of the laboratory tests were reviewed and assessed. For the first question, searches for studies were conducted in the MEDLINE database and IADR/AADR abtracts online with specific search and inclusion criteria. The outcome for each study was assessed on the basis of the statistical test applied in the study, and finally the number of studies with or without correlation was compiled. For the second question, results of the quantitative marginal analysis of Class V restorations published by the University of Zürich with the same test protocol and prospective clinical trials were searched that investigated the same materials for at least 2 years in Class V cavities. Pearson correlation coefficients were calculated for pooled data of materials and clinical outcome parameters such as retention loss, marginal discoloration, marginal integrity, and secondary caries. For the correlation of dye penetration and clinical outcome, studies on Class V restorations published by the same research institute were searched in MEDLINE that examined the same adhesive systems as the selected clinical trials. For the correlation bond strength/microleakage, 30 studies were included into the review, and for the correlation bond strength/gap analysis 18 studies. For both

  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. Subclinical hypothyroidism has little influences on muscle mass or strength in elderly people.

    Science.gov (United States)

    Moon, Min Kyong; Lee, You Jin; Choi, Sung Hee; Lim, Soo; Yang, Eun Joo; Lim, Jae-Young; Paik, Nam-Jong; Kim, Ki Woong; Park, Kyong Soo; Jang, Hak C; Cho, Bo Youn; Park, Young Joo

    2010-08-01

    Sarcopenia, the age-related decline in muscle mass, affects the muscle strength and muscle quality, and these changes decrease functional capacity. The prevalence of thyroid dysfunction increases with age, and changes in thyroid hormone level lead to neuromuscular deficits. We investigated the effects of subclinical hypothyroidism on the muscle mass, strength or quality in elderly people. One thousand one hundred eighteen subjects aged > or = 65 yr were randomly selected from a local population and classified into a euthyroid (280 men and 358 women), subclinically hypothyroid (61 men and 75 women), or overtly hypothyroid (7 men and 16 women) group. Although women with subclinical hypothyroidism had a higher prevalence of sarcopenia, defined according to the ratio of appendicular skeletal muscle mass to the square of height, muscle mass, strength or quality did not differ in relation to thyroid status in men or in women. Multivariate analysis including age, diabetes, hypertension, acute coronary event, alcohol, smoking, presence of pain, physical activity score, and lipid profile, showed that thyroid-stimulating hormone level was not associated with muscle mass, strength or quality. In conclusion, subclinical hypothyroidism has little influences on muscle mass, strength or quality, and may not be associated with sarcopenia.

  4. Early return to baseline range of motion and strength after anterior shoulder instability surgery: a Multicenter Orthopaedic Outcomes Network (MOON) shoulder group cohort study.

    Science.gov (United States)

    Buckwalter V, Joseph A; Wolf, Brian R; Glass, Natalie; Bollier, Matt; Kuhn, John E; Hettrich, Carolyn M

    2018-03-23

    Patients often return to higher-level activities and sports at 4 to 8 months after anterior shoulder stabilization procedures. It is unknown what percentage of patients have regained normal function at this time frame and what factors predict residual deficits, range of motion (ROM), and strength after anterior shoulder instability surgery. Ten participating sites throughout the United States enrolled patients in a prospective cohort study including primary, revision, arthroscopic, and open anterior stabilization procedures. Baseline demographic data and patient outcomes questionnaires were collected with initial physical examination, treatment, surgical findings, and surgical repair details. At the 6-month follow-up visit, ROM and strength measurements were collected and compared with preoperative measurements. There were 348 patients identified who underwent surgical treatment for anterior shoulder instability. Of these, 259 patients (74.0%) returned to baseline, and 89 (26.0%) did not return to baseline shoulder ROM (≥20° loss of ROM) or strength. A higher Beighton score (P = .01) and number of dislocations (P baseline ROM and strength at early follow-up. No surgical variables were found to influence return to baseline function, including open vs. arthroscopic surgery, primary vs. revision surgery, and number of suture anchors. By 4 to 8 months postoperatively, 76% of patients return to baseline ROM, 98% return to baseline strength, and 74% return to both baseline ROM and strength. An increased number of dislocations and generalized joint laxity were associated with failure to return to baseline ROM and strength at early follow-up after anterior shoulder instability surgery. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  5. Influence of the Reclaim from the Cordis Technology on the Core Sand Strength

    Directory of Open Access Journals (Sweden)

    Dańko J.

    2014-12-01

    Full Text Available The investigation results of the mechanical reclamation of spent moulding sands from the Cordis technology are presented in the paper. The quality assessment of the obtained reclaim and the influence of the reclaim fraction in a matrix on the core sand strength is given. The reclaim quality assessment was performed on the basis of the determination of losses on ignition, Na2O content on reclaim grains and pH values. The reclaim constituted 100%, 75% and 50% of the core sand matrix, for which the bending strength was determined. The matrix reclamation treatment was performed in the experimental rotor reclaimer RD-6. Spent sands were applied in as-delivered condition and after the heating to a temperature of 140 °C. Shaped samples for strength tests were made by shooting and hardening of sands in the warmbox technology.

  6. Geometry and gravity influences on strength capability

    Science.gov (United States)

    Poliner, Jeffrey; Wilmington, Robert P.; Klute, Glenn K.

    1994-01-01

    Strength, defined as the capability of an individual to produce an external force, is one of the most important determining characteristics of human performance. Knowledge of strength capabilities of a group of individuals can be applied to designing equipment and workplaces, planning procedures and tasks, and training individuals. In the manned space program, with the high risk and cost associated with spaceflight, information pertaining to human performance is important to ensuring mission success and safety. Knowledge of individual's strength capabilities in weightlessness is of interest within many areas of NASA, including workplace design, tool development, and mission planning. The weightless environment of space places the human body in a completely different context. Astronauts perform a variety of manual tasks while in orbit. Their ability to perform these tasks is partly determined by their strength capability as demanded by that particular task. Thus, an important step in task planning, development, and evaluation is to determine the ability of the humans performing it. This can be accomplished by utilizing quantitative techniques to develop a database of human strength capabilities in weightlessness. Furthermore, if strength characteristics are known, equipment and tools can be built to optimize the operators' performance. This study examined strength in performing a simple task, specifically, using a tool to apply a torque to a fixture.

  7. 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.

  8. Influence of Specimen Preparation and Test Methods on the Flexural Strength Results of Monolithic Zirconia Materials.

    Science.gov (United States)

    Schatz, Christine; Strickstrock, Monika; Roos, Malgorzata; Edelhoff, Daniel; Eichberger, Marlis; Zylla, Isabella-Maria; Stawarczyk, Bogna

    2016-03-09

    The aim of this work was to evaluate the influence of specimen preparation and test method on the flexural strength results of monolithic zirconia. Different monolithic zirconia materials (Ceramill Zolid (Amann Girrbach, Koblach, Austria), Zenostar ZrTranslucent (Wieland Dental, Pforzheim, Germany), and DD Bio zx² (Dental Direkt, Spenge, Germany)) were tested with three different methods: 3-point, 4-point, and biaxial flexural strength. Additionally, different specimen preparation methods were applied: either dry polishing before sintering or wet polishing after sintering. Each subgroup included 40 specimens. The surface roughness was assessed using scanning electron microscopy (SEM) and a profilometer whereas monoclinic phase transformation was investigated with X-ray diffraction. The data were analyzed using a three-way Analysis of Variance (ANOVA) with respect to the three factors: zirconia, specimen preparation, and test method. One-way ANOVA was conducted for the test method and zirconia factors within the combination of two other factors. A 2-parameter Weibull distribution assumption was applied to analyze the reliability under different testing conditions. In general, values measured using the 4-point test method presented the lowest flexural strength values. The flexural strength findings can be grouped in the following order: 4-point strength values than prepared before sintering. The Weibull moduli ranged from 5.1 to 16.5. Specimens polished before sintering showed higher surface roughness values than specimens polished after sintering. In contrast, no strong impact of the polishing procedures on the monoclinic surface layer was observed. No impact of zirconia material on flexural strength was found. The test method and the preparation method significantly influenced the flexural strength values.

  9. Influence of non-metallic inclusions on fatigue strength of high manganese steel

    International Nuclear Information System (INIS)

    Maekawa, I.; Shibata, H.; Lee, J.H.; Nishida, Shin-ichi

    1991-01-01

    Six series of high manganese austenitic steel, which contain different inclusion quantity, were prepared. Fatigue experiments, tensile tests and Charpy tests were carried out. Influence of non-metallic inclusion and of temperature on the stress intensity threshold, fatigue crack propagation behavior, elastic-plastic fracture toughness and Charpy value were studied at room temperature and low temperature. In general, strength of this high manganese steel was reduced with increase of inclusion content. Influences of the direction of elongated inclusion with regard to the rolling direction on their strengths were also discussed based on SEM observation and numerical analysis for the stress concentration at a crack tip when an inclusion was near by the tip. According to these results, an inclusion acted as an obstacle to crack propagation for LT specimen. The roughness of fracture surface of ST specimen was larger than that of SL specimen, and the crack growth rate of the former was less than that of the latter. Fatigue life was increased with decrease of temperature, and mechanical parameters such as ΔK th and J 1c were decreased with increase of temperature. The Charpy value decreased clearly with decrease of temperature

  10. Influence of Casting Section Thickness on Fatigue Strength of Austempered Ductile Iron

    Science.gov (United States)

    Olawale, J. O.; Ibitoye, S. A.

    2017-10-01

    The influence of casting section thickness on fatigue strength of austempered ductile iron was investigated in this study. ASTM A536 65-45-12 grade of ductile iron was produced, machined into round samples of 10, 15, 20 and 25 mm diameter, austenitized at a temperature of 820 °C, quenched into an austempering temperature (TA) of 300 and 375 °C and allowed to be isothermally transformed at these temperatures for a fixed period of 2 h. From the samples, fatigue test specimens were machined to conform to ASTM E-466. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) methods were used to characterize microstructural morphology and phase distribution of heat-treated samples. The fatigue strength decreases as the section thickness increases. The SEM image and XRD patterns show a matrix of acicular ferrite and carbon-stabilized austenite with ferrite coarsening and volume fraction of austenite reducing as the section thickness increases. The study concluded that the higher the value of carbon-stabilized austenite the higher the fatigue strength while it decreases as the ausferrite structure becomes coarse.

  11. Influence of processing factors over concrete strength.

    Science.gov (United States)

    Kara, K. A.; Dolzhenko, A. V.; Zharikov, I. S.

    2018-03-01

    Construction of facilities of cast in-situ reinforced concrete poses additional requirements to quality of material, peculiarities of the construction process may sometimes lead to appearance of lamination planes and inhomogeneity of concrete, which reduce strength of the material and structure as a whole. Technology compliance while working with cast in-situ concrete has a significant impact onto the concrete strength. Such process factors as concrete curing, vibration and compaction of the concrete mixture, temperature treatment, etc., when they are countered or inadequately followed lead to a significant reduction in concrete strength. Here, the authors experimentally quantitatively determine the loss of strength in in-situ cast concrete structures due to inadequate following of process requirements, in comparison with full compliance.

  12. Incidental emotions influence risk preference and outcome evaluation.

    Science.gov (United States)

    Zhao, Ding; Gu, Ruolei; Tang, Ping; Yang, Qiwei; Luo, Yue-Jia

    2016-10-01

    Incidental emotions, which are irrelevant to the current decision, play a significant role in the decision-making process. In this study, to investigate the influence of incidental emotions on behavioral, psychological, and electrophysiological responses in the process of decision making, participants were required to perform a monetary gambling task. During the selection stage, an emotional picture, which was chosen from the Chinese Affective Picture System and fell into one of three categories: negative, neutral, and positive, was presented between two alternatives (small/large amount of bet). The pictures were provided to induce incidental emotions. ERPs and self-rating emotional experiences to outcome feedback were recorded during the task. Behavioral results showed that positive incidental emotions elicited risk preference, but emotional experiences to outcome feedback were not influenced by incidental emotions. The feedback-related negativity amplitudes were larger in the positive emotion condition than in the negative and neutral emotion conditions for small outcomes (including wins and losses), whereas there was no difference between the three conditions for large outcomes. In addition, the amplitudes of P3 were reduced overall in the negative emotion condition. We suggest that incidental emotions have modulated both the option assessment stage (manifested in behavioral choices) and the outcome evaluation stage (manifested in ERP amplitudes) of decision making unconsciously (indicated by unchanged subjective emotional experiences). The current findings have expanded our understanding of the role of incidental emotion in decision making. © 2016 Society for Psychophysiological Research.

  13. Influence of bleaching and desensitizing gel on bond strength of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Fernanda Alves Rodrigues Britto

    2015-04-01

    Full Text Available OBJECTIVE: The objective of this study was to assess, in vitro, the influence of bleaching gel and the use of desensitizing agent over bond strength of ceramic brackets bonded to bovine enamel. METHODS: One hundred bovine incisors were selected and randomly divided into five groups (n = 20: Group 1, control group (without bleaching; Group 2, bleached with 35% hydrogen peroxide; Group 3, bleached with 35% hydrogen peroxide (three applications, 15 minutes each and desensitizing agent applied for 10 minutes; Group 4, bleached with 35% hydrogen peroxide for 40 minutes; Group 5, bleached with 35% hydrogen peroxide for 40 minutes with desensitizing agent applied for 10 minutes. Brackets were bonded 7 days after bleaching and submitted to shear bond strength test after 24 hours at a compression rate of 1 mm/minute. After fracture, the adhesive remnant index (ARI was assessed under stereoscopic at 40 x magnification. Shear strength data (MPa were submitted to one-way ANOVA and Tukey's test with significance level set at 5%. RESULTS: Group 5 (29.33 MPa showed significantly higher bond strength than Group 1 (19.19 MPa, Group 2 (20.59 MPa and Group 4 (23.25 MPa, but with no difference in comparison to Group 3. There was no significant difference among the other groups. The adhesive remnant index showed predominance of score 3, that is, all resin remained adhered to enamel for all groups. CONCLUSION: Bleaching with 35% hydrogen peroxide with calcium associated with desensitizing agent application produced higher bond strength values of brackets bonded to bovine enamel.

  14. On the influence of moisture and load variations on the strength behavior of wood

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    2005-01-01

    Abstract: It is demonstrated in this paper that the influence of moisture- and load variations on lifetime and residual strength (re-cycle strength) of wood can be considered by theories previously developed by the author. The common, controlling factor is creep, which can be modified very easily...... by introducing a special moisture dependent relaxation time in the well-known Power-Law creep expression. Because basic failure mechanisms in wood are invariant with respect to loading modes, it is suggested that a number of methods used in design of wood structures can be generalized/simplified to apply...

  15. Does progressive resistance strength training as additional training have any measured effect on functional outcomes in older hospitalized patients?

    DEFF Research Database (Denmark)

    Tibaek, Sigrid; Andersen, Christina W.; Pedersen, Sigrid F

    2014-01-01

    OBJECTIVE: To evaluate the effect of progressive resistance strength training as additional training measured on functional outcomes in older hospitalized patients. DESIGN: A single-blinded randomized controlled trial. SETTING: Department of Geriatric Rehabilitation in university hospital...

  16. Influence of Cyclic Straining on Fatigue, Deformation, and Fracture Behavior of High-Strength Alloy Steel

    Science.gov (United States)

    Manigandan, K.; Srivatsan, T. S.; Vasudevan, V. K.; Tammana, D.; Poorganji, B.

    2016-01-01

    In this paper, the results of a study on microstructural influences on mechanical behavior of the high-strength alloy steel Tenax™ 310 are presented and discussed. Under the influence of fully reversed strain cycling, the stress response of this alloy steel revealed softening from the onset of deformation. Cyclic strain resistance exhibited a linear trend for the variation of both elastic strain amplitude with reversals-to-failure, and plastic strain amplitude with reversals-to-failure. Fracture morphology was essentially the same at the macroscopic level over the entire range of cyclic strain amplitudes examined. However, at the fine microscopic level, this high-strength alloy steel revealed fracture to be mixed-mode with features reminiscent of "locally" ductile and brittle mechanisms. The macroscopic mechanisms governing stress response at the fine microscopic level, resultant fatigue life, and final fracture behavior are presented and discussed in light of the mutually interactive influences of intrinsic microstructural effects, deformation characteristics of the microstructural constituents during fully reversed strain cycling, cyclic strain amplitude, and resultant response stress.

  17. Positive psychological strengths and school engagement in primary school children

    Directory of Open Access Journals (Sweden)

    Bronwyn Wilkins

    2015-12-01

    Full Text Available A sizeable body of research has investigated the impact of specific character strengths or traits on significant outcomes. Some recent research is beginning to consider the effects of groups of strengths, combined as a higher order variable and termed covitality. This study investigated the combined influence of four positive character traits, gratitude, optimism, zest and persistence, upon school engagement, within a sample of 112 Australian primary school students. The combined effect of these four traits, in defining covitality as a higher or second-order factor within a path analysis, was found to predict relatively higher levels of school engagement and pro-social behaviour.

  18. The influence of using accelerator addition on High strength self-compacting concrete (HSSCC) in case of enhancement early compressive strength and filling ability parameters

    Science.gov (United States)

    Wibowo; Fadillah, Y.

    2018-03-01

    Efficiency in a construction works is a very important thing. Concrete with ease of workmanship and rapid achievement of service strength will to determine the level of efficiency. In this research, we studied the optimization of accelerator usage in achieving performance on compressive strength of concrete in function of time. The addition of variation of 0.3% - 2.3% to the weight of cement gives a positive impact of the rapid achievement of hardened concrete, however the speed of increasing of concrete strength achievement in term of time influence present increasing value of filling ability parameter of self-compacting concrete. The right composition of accelerator aligned with range of the values standard of filling ability parameters of HSSCC will be an advantage guidance for producers in the ready-mix concrete industry.

  19. The influence of chromosome density variations on the increase in nuclear disorder strength in carcinogenesis

    International Nuclear Information System (INIS)

    Kim, Jun Soo; Pradhan, Prabhakar; Backman, Vadim; Szleifer, Igal

    2011-01-01

    Microscopic structural changes have long been observed in cancer cells and used as a marker in cancer diagnosis. Recent development of an optical technique, partial-wave spectroscopy (PWS), enabled more sensitive detection of nanoscale structural changes in early carcinogenesis in terms of the disorder strength related to density variations. These nanoscale alterations precede the well-known microscopic morphological changes. We investigate the influence of nuclear density variations due to chromosome condensation on changes of disorder strength by computer simulations of model chromosomes. Nuclear configurations with different degrees of chromosome condensation are realized from simulations of decondensing chromosomes and the disorder strength is calculated for these nuclear configurations. We found that the disorder strength increases significantly for configurations with slightly more condensed chromosomes. Coupled with PWS measurements, the simulation results suggest that the chromosome condensation and the resulting spatial density inhomogeneity may represent one of the earliest events in carcinogenesis

  20. A randomized controlled trial on the effectiveness of strength training on clinical and muscle cellular outcomes in patients with prostate cancer during androgen deprivation therapy: rationale and design

    International Nuclear Information System (INIS)

    Thorsen, Lene; Nilsen, Tormod S; Raastad, Truls; Courneya, Kerry S; Skovlund, Eva; Fosså, Sophie D

    2012-01-01

    Studies indicate that strength training has beneficial effects on clinical health outcomes in prostate cancer patients during androgen deprivation therapy. However, randomized controlled trials are needed to scientifically determine the effectiveness of strength training on the muscle cell level. Furthermore, close examination of the feasibility of a high-load strength training program is warranted. The Physical Exercise and Prostate Cancer (PEPC) trial is designed to determine the effectiveness of strength training on clinical and muscle cellular outcomes in non-metastatic prostate cancer patients after high-dose radiotherapy and during ongoing androgen deprivation therapy. Patients receiving androgen deprivation therapy for 9-36 months combined with external high-dose radiotherapy for locally advanced prostate cancer are randomized to an exercise intervention group that receives a 16 week high-load strength training program or a control group that is encouraged to maintain their habitual activity level. In both arms, androgen deprivation therapy is continued until the end of the intervention period. Clinical outcomes are body composition (lean body mass, bone mineral density and fat mass) measured by Dual-energy X-ray Absorptiometry, serological outcomes, physical functioning (muscle strength and cardio-respiratory fitness) assessed with physical tests and psycho-social functioning (mental health, fatigue and health-related quality of life) assessed by questionnaires. Muscle cellular outcomes are a) muscle fiber size b) regulators of muscle fiber size (number of myonuclei per muscle fiber, number of satellite cells per muscle fiber, number of satellite cells and myonuclei positive for androgen receptors and proteins involved in muscle protein degradation and muscle hypertrophy) and c) regulators of muscle fiber function such as proteins involved in cellular stress and mitochondrial function. Muscle cellular outcomes are measured on muscle cross sections and

  1. Influence of Post Weld Heat Treatment on Strength of Three Aluminum Alloys Used in Light Poles

    Directory of Open Access Journals (Sweden)

    Craig C. Menzemer

    2016-03-01

    Full Text Available The conjoint influence of welding and artificial aging on mechanical properties were investigated for extrusions of aluminum alloy 6063, 6061, and 6005A. Uniaxial tensile tests were conducted on the aluminum alloys 6063-T4, 6061-T4, and 6005A-T1 in both the as-received (AR and as-welded (AW conditions. Tensile tests were also conducted on the AR and AW alloys, subsequent to artificial aging. The welding process used was gas metal arc (GMAW with spray transfer using 120–220 A of current at 22 V. The artificial aging used was a precipitation heat treatment for 6 h at 182 °C (360 °F. Tensile tests revealed the welded aluminum alloys to have lower strength, both for yield and ultimate tensile strength, when compared to the as-received un-welded counterpart. The beneficial influence of post weld heat treatment (PWHT on strength and ductility is presented and discussed in terms of current design provisions for welded aluminum light pole structures.

  2. The influence of size and structure of metal orthodontic bracket base on bond strength on tooth enamel

    Directory of Open Access Journals (Sweden)

    Mitić Vladimir

    2009-01-01

    Full Text Available Introduction. The factors which may influence the bond strength of the applied orthodontic brackets on the tooth surface are the size and structure of the bracket base. Objective. The aim of the paper was to investigate the influence of size and shape of different types of brackets on bond strength on the enamel and analyze the remaining quality of adhesive material on the tooth surface after debonding of orthodontic brackets (adhesive remnant index - ARI. Methods. In this study, three types of metal brackets of different sizes and shapes of Dentaurum manufacturer were used (Utratrimm, Equilibrium 2, Discovery, Dentaurum, Inspringen, Germany. The brackets were applied onto the middle part of the anatomic crowns of buccal surfaces of 30 premolars extracted for orthodontic reasons. In addition, the pre-treatment of teeth by 37% orthophosphoric acid and adhesive material System1+ (Dentaurum, Germany were used. Results. The mean value of the bonded brackets bond strength of Discovery type after debonding was 8.67±0.32 MPa, while the value of the bonded brackets bond strength of Equilibrium 2 type amounted to 8.62±0.22 MPa. The value of the bonded brackets bond strength of Ultratrimm type after debonding was 8.22±0.49 MPa. There were no statistical differences in the values of bond strength regarding all three groups of the investigated orthodontic brackets (F=4.56; p<0.05. Conclusion. The base size and design of metal orthodontic brackets did not play a significant role in bond strength, while the values of ARI index were identical in all three investigated groups.

  3. Influence of acute static stretching on the behavior of maximum muscle strength

    Directory of Open Access Journals (Sweden)

    Carmen Lúcia Borges Bastos

    2014-06-01

    Full Text Available The aim of this study was to compare the influence of acute static stretching on maximal muscle strength (1RM. The non-probabilistic sample consisted of 30 subjects split into two groups: static stretching (SS= 15 and without stretching group (WS= 15. Muscle strength evaluation (1RM was conducted with a Dynamometer model 32527pp400 Pound push / pull devices coupled in knee extension (KE and bench press (BP. The Wilcoxon test for intragroup comparisons and the Kruskal-Wallis test for comparisons between groups (p< 0.05 were selected. There were no significant differences (p> 0.05 between the SS and WS in exercise KE and BP. Therefore, it can be concluded that there was no reduction in the performance of 1RM performing the exercises KE and BP when preceded by static stretching.

  4. Influence of intrapulpal pressure simulation on the bond strength of adhesive systems to dentin

    Directory of Open Access Journals (Sweden)

    Marcio Vivan Cardoso

    2008-06-01

    Full Text Available The purpose of this study was to evaluate the influence of intrapulpal pressure simulation on the bonding effectiveness of etch & rinse and self-etch adhesives to dentin. Eighty sound human molars were distributed into eight groups, according to the permeability level of each sample, measured by an apparatus to assess hydraulic conductance (Lp. Thus, a similar mean permeability was achieved in each group. Three etch & rinse adhesives (Prime & Bond NT - PB, Single Bond -SB, and Excite - EX and one self-etch system (Clearfil SE Bond - SE were employed, varying the presence or absence of an intrapulpal pressure (IPP simulation of 15 cmH2O. After adhesive and restorative procedures were carried out, the samples were stored in distilled water for 24 hours at 37°C, and taken for tensile bond strength (TBS testing. Fracture analysis was performed using a light microscope at 40 X magnification. The data, obtained in MPa, were then submitted to the Kruskal-Wallis test ( a = 0.05. The results revealed that the TBS of SB and EX was significantly reduced under IPP simulation, differing from the TBS of PB and SE. Moreover, SE obtained the highest bond strength values in the presence of IPP. It could be concluded that IPP simulation can influence the bond strength of certain adhesive systems to dentin and should be considered when in vitro studies are conducted.

  5. Influence of paternal age on perinatal outcomes.

    Science.gov (United States)

    Hurley, Emily G; DeFranco, Emily A

    2017-11-01

    There is an increasing trend to delay childbearing to advanced parental age. Increased risks of advanced maternal age and assisted reproductive technologies are widely accepted. There are limited data regarding advanced paternal age. To adequately counsel patients on risk, more research regarding advanced paternal age is necessary. We sought to determine the influence of paternal age on perinatal outcomes, and to assess whether this influence differs between pregnancies achieved spontaneously and those achieved with assisted reproductive technology. A population-based retrospective cohort study of all live births in Ohio from 2006 through 2012 was completed. Data were evaluated to determine if advanced paternal age is associated with an increased risk of adverse outcomes in pregnancies. The analysis was stratified by status of utilization of assisted reproductive technology. Generalized linear regression models assessed the association of paternal age on pregnancy complications in assisted reproductive technology and spontaneously conceived pregnancies, after adjusting for maternal age, race, multifetal gestation, and Medicaid status, using Stata software (Stata, Release 12; StataCorp, College Station, TX). Paternal age was documented in 82.2% of 1,034,552 live births in Ohio during the 7-year study period. Paternal age ranged from 12-87 years, with a median of 30 (interquartile range, 26-35) years. Maternal age ranged from 11-62 years, with a median of 27 (interquartile range, 22-31) years. The use of assisted reproductive technology in live births increased as paternal age increased: 0.1% 60 years, P risk factors, increased paternal age was not associated with a significant increase in the rate of preeclampsia, preterm birth, fetal growth restriction, congenital anomaly, genetic disorder, or neonatal intensive care unit admission. The influence of paternal age on pregnancy outcomes was similar in pregnancies achieved with and without assisted reproductive

  6. Does Histologic Subtype Influence the Post-Operative Outcome in Spinal Meningioma?

    Science.gov (United States)

    Zham, Hanieh; Moradi, Afshin; Rakhshan, Azadeh; Zali, Alireza; Rahbari, Ali; Raee, Mohammadreza; Ashrafi, Farzad; Ahadi, Mahsa; Larijani, Leila; Baikpour, Masoud; Khayamzadeh, Maryam

    2016-04-01

    Postoperative outcome of spinal meningiomas is an important issue in surgery decision-making. There are limited and conflicting data in the literature about the prognostic factors influencing recovery, especially about the histopathologic subtypes. This study was carried out to evaluate the effect of some of these factors on postoperative outcome. This study was performed on 39 patients operated for spinal meningioma between October 1998 and January 2012; their histopathologic subtype was determined according to WHO criteria. The follow up period ranged between 8 - 120 months. The influence of histopathologic subtype, grade, age, sex, surgical approach, local adhesion and anatomical location was assessed according to Frankel classification of neurologic deficit. From a total number of 39 spinal meningiomas, 34 cases were WHO grade I, from which 15 cases were psammomatous, 7 cases were meningothelial, 9 cases were transitional and 3 cases were fibroblastic. Five cases were grade II, 3 of which had clear cell appearance and the remaining 2 had chordoid appearance. The mean age was 51.6 (22 to 76) years; 25 cases were female and 14 cases were male. This study revealed that grade II meningioma cases had poor prognosis in all 5 cases and psammomatous subtype had poor postoperative outcome in 40% of cases while the other subtypes had good outcome in all cases (P = 0.026). Cervical location of the tumor was also related with poor outcome in 37.5% of the cases, while 22.5% had poor outcome in other locations (P = 0.029). Age below and above 45 years and sex had no significant influence on the outcome. Spinal meningiomas of psammomatous type and grade II spinal meningiomas are associated with less favorable postoperative neurologic outcome. Cervical location has also a negative correlation with a good outcome.

  7. The Influence of Radiographic Severity on the Relationship between Muscle Strength and Joint Loading in Obese Knee Osteoarthritis Patients

    Directory of Open Access Journals (Sweden)

    Jens Aaboe

    2011-01-01

    Full Text Available Objective. To investigate the relationship between knee muscle strength and the external knee adduction moment during walking in obese knee osteoarthritis patients and whether disease severity influences this relationship. Methods. This cross-sectional study included 136 elderly obese (BMI>30 adults with predominant medial knee osteoarthritis. Muscle strength, standing radiographic severity as measured by the Kellgren and Lawrence scale, and the peak external knee adduction moment were measured at self-selected walking speed. Results. According to radiographic severity, patients were classified as “less severe” (KL 1-2, N=73 or “severe” (KL 3-4, N=63. A significant positive association was demonstrated between the peak knee adduction moment and hamstring muscle strength in the whole cohort (P=.047. However, disease severity did not influence the relationship between muscle strength and dynamic medial knee joint loading. Severe patients had higher peak knee adduction moment and more varus malalignment (P<.001. Conclusion. Higher hamstring muscle strength relates to higher estimates of dynamic knee joint loading in the medial compartment. No such relationship existed for quadriceps muscle strength. Although cross sectional, the results suggest that hamstrings function should receive increased attention in future studies and treatments that aim at halting disease progression.

  8. Manual and oral apraxia in acute stroke, frequency and influence on functional outcome

    DEFF Research Database (Denmark)

    Pedersen, P M; Jørgensen, H S; Kammersgaard, L P

    2001-01-01

    To determine the frequency of manual and oral apraxia in acute stroke and to examine the influence of these symptoms on functional outcome.......To determine the frequency of manual and oral apraxia in acute stroke and to examine the influence of these symptoms on functional outcome....

  9. Importance of tie strengths in the prisoner's dilemma game on social networks

    International Nuclear Information System (INIS)

    Xu, Bo; Liu, Lu; You, Weijia

    2011-01-01

    Though numerous researches have shown that tie strengths play a key role in the formation of collective behavior in social networks, little work has been done to explore their impact on the outcome of evolutionary games. In this Letter, we studied the effect of tie strength in the dynamics of evolutionary prisoner's dilemma games by using online social network datasets. The results show that the fraction of cooperators has a non-trivial dependence on tie strength. Weak ties, just like previous researches on epidemics and information diffusion have shown, play a key role by the maintenance of cooperators in evolutionary prisoner's dilemma games. -- Highlights: → Tie strength is used to measure heterogeneous influences of different pairs of nodes. → Weak ties play a role in maintaining cooperation in prisoner's dilemma games. → Micro-dynamics of nodes are illustrated to explain the conclusion.

  10. Influence of rivet to sheet edge distance on fatigue strength of self-piercing riveted aluminium joints

    OpenAIRE

    Li, Dezhi; Han, Li; Thornton, Martin; Shergold, Mike

    2012-01-01

    Self-piercing riveting (SPR) is one of the main joining methods for lightweight aluminium automotive body structures due to its advantages. In order to further optimise the structure design and reduce the weight but without compromising strength, reduction of redundant materials in the joint flange area can be considered. For this reason, the influence of rivet to sheet edge distance on the fatigue strengths of self-piercing riveted joints was studied. Five edge distances, 5 mm, 6 mm, 8 mm, 1...

  11. Central Bank Financial Strength and Policy Performance; An Econometric Evaluation

    OpenAIRE

    Peter Stella; Ulrich H Klueh

    2008-01-01

    The financial health of central banks and its relation to policy outcomes has recently been recognized as an important policy issue. While case study evidence clearly indicates that weak central bank finances can hamper effective policy implementation, the question of whether central bank financial strength influences policy performance remains controversial. This is due, in part, to a lack of econometric evidence. The paper presents a first step toward filling this gap, by providing a quanti...

  12. Influence of variables on the consolidation and unconfined compressive strength of crushed salt: Technical report

    International Nuclear Information System (INIS)

    Pfeifle, T.W.; Senseny, P.E.; Mellegard, K.D.

    1987-01-01

    Eight hydrostatic compression creep tests were performed on crushed salt specimens fabricated from Avery Island dome salt. Following the creep test, each specimen was tested in unconfined compression. The experiments were performed to assess the influence of the following four variables on the consolidation and unconfined strength of crushed salt: grain size distribution, temperature, time, and moisture content. The experiment design comprised a half-fraction factorial matrix at two levels. The levels of each variable investigated were grain size distribution, uniform-graded and well-graded (coefficient of uniformity of 1 and 8); temperature 25 0 C and 100 0 C; time, 3.5 x 10 3 s and 950 x 10 3 s (approximately 60 minutes and 11 days, respectively); and moisture content, dry and wet (85% relative humidity for 24 hours). The hydrostatic creep stress was 10 MPa. The unconfined compression tests were performed at an axial strain rate of 1 x 10 -5 s -1 . Results show that the variables time and moisture content have the greatest influence on creep consolidation, while grain size distribution and, to a somewhat lesser degree, temperature have the greatest influence on total consolidation. Time and moisture content and the confounded two-factor interactions between either grain size distribution and time or temperature and moisture content have the greatest influence on unconfined strength. 7 refs., 7 figs., 11 tabs

  13. Risk factors influencing the treatment outcome in diabetic macular oedema

    Directory of Open Access Journals (Sweden)

    Gupta Amod

    1996-01-01

    Full Text Available A multivariate analysis was done on 96 eyes to evaluate the effect of various risk factors on the final visual outcome after laser photocoagulation for clinically significant macular oedema (CSME in diabetic retinopathy. Advanced age of the patient, large size of CSME and poor baseline visual acuity were found to be significantly associated with poorer outcome (p<0.05. The association of nephropathy and hypertension with poorer visual outcome was of boderline significance (p = 0.054 and 0.07, respectively. Wavelength of the laser (argon or krypton used for treatment did not significantly influence the outcome.

  14. Influence of Fly Ash on the Compressive Strength of Foamed Concrete at Elevated Temperature

    Directory of Open Access Journals (Sweden)

    Ahmad H.

    2014-01-01

    Full Text Available Foamed concrete is a lightweight concrete that is widely used in the construction industry recently. This study was carried out to investigate the influence of fly ash as a cement replacement material to the residual compressive strength of foamed concrete subjected to elevated temperature. For this study, the foamed concrete density was fixed at 1300 kg/m3 and the sand-cement ratio and water-cement was set at 1:2 and 0.45, respectively. The samples were prepared and tested at the age of 28 days. Based on the results, it has been found that with 25% inclusion of fly ash, the percentage of compressive strength loss was decreased by 3 – 50%.

  15. Influence of aggregate characteristics on the compressive strength of normal weight concrete

    International Nuclear Information System (INIS)

    Qureshi, M.A.; Aslam, M.

    2015-01-01

    Experimental investigations on the properties of concrete have been performed around the globe and their correlation is interpreted in relevant design codes. The structural behavior of cement concrete significantly relies on the material resources, properties of the aggregates constituting the concrete and the local construction practice. These factors vary from place to place. Therefore, the compressive strength of concrete prepared from the aggregates available in one locality may not be directly applicable to the other areas. The purpose of this study is to evaluate the Influence of locally available coarse aggregates on the compressive strength of normal weight concrete (NWC) prepared under local environmental conditions of district Khairpur Mir's, Sindh, Pakistan. The coarse aggregates were collected from five different quarries in the vicinity of Khairpur Mir's, Pakistan. In total; 180 cubes were tested. 10 different batches were formed in order to arrange individual characterization of concrete. Each batch was contained of 18 cubes and each quarry contains 2 batches making a total of 36 cube with four different ratios for each quarry. Dry density and compressive strength of concrete was calculated and a comparison is provided as a guideline for the future construction work in the local community. (author)

  16. Factors influencing the creep strength of hot pressed beryllium

    International Nuclear Information System (INIS)

    Webster, D.; Crooks, D.D.

    1975-01-01

    The parameters controlling the creep strength of hot pressed beryllium block have been determined. Creep strength was improved by a high initial dislocation density, a coarse grain size, and a low impurity content. The impurities most detrimental to creep strength were found to be aluminum, magnesium, and silicon. A uniform distribution of BeO was found to give creep strength which was inferior to a grain boundary distribution. The creep strength of very high purity, hot isostatically pressed beryllium was found to compare favorably with that of other more commonly used high temperature metals

  17. Factors Influencing the Outcomes in Extradural Haematoma Patients

    African Journals Online (AJOL)

    neurosurgical emergencies and are one of the most common causes of mortality and disability after traumatic brain injury. This study aimed at evaluating the current management and factors that influence outcome in patients treated for extradural hematoma in an African setting. Methods: A total of 224 consecutive patients ...

  18. The dance’s influence on muscle strength of lower limbs on the elderly

    Directory of Open Access Journals (Sweden)

    Joseane Rodrigues da Silva

    2011-09-01

    Full Text Available The aim of this study was to evaluate the influence of dance in the lower limb muscle strength on the elderly. This research has a qualitative-quantitative aproach. The sample was composed by ten elderly of both sexes, who practiced ballroom dancing classes during twelve weeks. The evaluation was performed before and after the classes and it was composed by a questionnaire with personal data and medical history, “test stand and sit in 30 seconds” and a semi-structured interview with a guiding question regarding the perception of muscular strength of the elderly. The quantitative analysis was performed using the Student’s t-test with a significance level of p<0,05%. The qualitative analysis was made according directions proposed by Minayo (1994. The evaluation of muscle strength measured by the test of sitting and standing up, showed that four participants had a decreased and six had an increase in the number of movements executed, but not existed a significant statistical difference between the values before and after intervention (p=0,1934. However, the speech of the participants showed an improvement on the perception in relation muscle strength, mobility, joviality and self-esteem. It suggests that the effect of the dance, performed in the frequency used in this study, has an effect on the well-being and psychosocial sphere of the elderly. Playful activities in physical therapy performed by groups, bringing benefits, however, it should not be an isolated activity, it should be associated with a specific training to improve muscle strength related to the needs of each elderly.

  19. Influence of silica fume and fly ash on hydration, microstructure and strength of cement based mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Weng, Kaimao

    1992-10-01

    The influence of fly ash and silica fume on the hydration, microstructure and strength of cement-based mixtures was investigated. A literature review of the hydration processes, compressive strength development, and microstructure of Portland cement is presented, followed by description of materials and specimens preparation and experimental methodology. It was found that silica fume retards cement hydration at low water/concrete ratios. It reduces calcium hydroxide significantly and increases the amount of hydrates at early ages. Fly ash retards hydration more significantly at high water/concrete ratios than at low ratios. The combination of silica fume and fly ash further retards hydration at one day. Silica fume dominates the reaction with calcium hydroxide. Silica fume significantly increases early strength of mortars and concrete, while fly ash reduces early strength. Silica fume can substantially increase strength of fly ash mortar and concrete after 7 days. Silica fume refines pores in the range 100-500 A, while fly ash mortars exhibit gradual pore refinement as hydration proceeds. Silica fume dominates the pore refinement if used with fly ash. 89 refs., 74 figs., 16 tabs.

  20. EVALUATING THE INFLUENCE OF MASSAGE ON LEG STRENGTH, SWELLING, AND PAIN FOLLOWING A HALF-MARATHON

    Directory of Open Access Journals (Sweden)

    Peter M. Tiidus

    2004-11-01

    Full Text Available Massage therapy is commonly used following endurance running races with the expectation that it will enhance post-run recovery of muscle function and reduce soreness. A limited number of studies have reported little or no influence of massage therapy on post-exercise muscle recovery. However, no studies have been conducted in a field setting to assess the potential for massage to influence muscle recovery following an actual endurance running race. To evaluate the potential for repeated massage therapy interventions to influence recovery of quadriceps and hamstring muscle soreness, recovery of quadriceps and hamstring muscle strength and reduction of upper leg muscle swelling over a two week recovery period following an actual road running race. Twelve adult recreational runners (8 male, 4 female completed a half marathon (21.1 km road race. On days 1,4, 8, and 11 post-race, subjects received 30 minutes of standardized massage therapy performed by a registered massage therapist on a randomly assigned massage treatment leg, while the other (control leg received no massage treatment. Two days prior to the race (baseline and preceding the treatments on post-race days 1, 4, 8, and 11 the following measures were conducted on each of the massage and control legs: strength of quadriceps and hamstring muscles, leg swelling, and soreness perception. At day 1, post-race quadriceps peak torque was significantly reduced (p 0.05. All measures had returned to baseline at day 11. Massage did not affect the recovery of muscles in terms of physiological measures of strength, swelling, or soreness. However, questionnaires revealed that 7 of the 12 participants perceived that the massaged leg felt better upon recovery.

  1. Activity limitations and factors influencing functional outcome of ...

    African Journals Online (AJOL)

    EB

    2013-09-03

    Sep 3, 2013 ... life and satisfaction with life1,22. A recent study conducted among community dwelling stroke survivors found functional ability and independence to be the strongest predictor of, and were responsible for the greatest variance on participation22. For determining the factors influencing outcome with the use ...

  2. Influence of Eco-Friendly Mineral Additives on Early Age Compressive Strength and Temperature Development of High-Performance Concrete

    Science.gov (United States)

    Kaszynska, Maria; Skibicki, Szymon

    2017-12-01

    High-performance concrete (HPC) which contains increased amount of both higher grade cement and pozzolanic additives generates more hydration heat than the ordinary concrete. Prolonged periods of elevated temperature influence the rate of hydration process in result affecting the development of early-age strength and subsequent mechanical properties. The purpose of the presented research is to determine the relationship between the kinetics of the heat generation process and the compressive strength of early-age high performance concrete. All mixes were based on the Portland Cement CEM I 52.5 with between 7.5% to 15% of the cement mass replaced by the silica fume or metakaolin. Two characteristic for HPC water/binder ratios of w/b = 0.2 and w/b = 0.3 were chosen. A superplasticizer was used to maintain a 20-50 mm slump. Compressive strength was determined at 8h, 24h, 3, 7 and 28 days on 10x10x10 cm specimens that were cured in a calorimeter in a constant temperature of T = 20°C. The temperature inside the concrete was monitored continuously for 7 days. The study determined that the early-age strength (t<24h) of concrete with reactive mineral additives is lower than concrete without them. This is clearly visible for concretes with metakaolin which had the lowest compressive strength in early stages of hardening. The amount of the superplasticizer significantly influenced the early-age compressive strength of concrete. Concretes with additives reached the maximum temperature later than the concretes without them.

  3. Measuring outcomes in adult spinal deformity surgery: a systematic review to identify current strengths, weaknesses and gaps in patient-reported outcome measures.

    Science.gov (United States)

    Faraj, Sayf S A; van Hooff, Miranda L; Holewijn, Roderick M; Polly, David W; Haanstra, Tsjitske M; de Kleuver, Marinus

    2017-08-01

    Adult spinal deformity (ASD) causes severe disability, reduces overall quality of life, and results in a substantial societal burden of disease. As healthcare is becoming more value based, and to facilitate global benchmarking, it is critical to identify and standardize patient-reported outcome measures (PROMs). This study aims to identify the current strengths, weaknesses, and gaps in PROMs used for ASD. Studies were included following a systematic search in multiple bibliographic databases between 2000 and 2015. PROMs were extracted and linked to the outcome domains of WHO's International Classification of Functioning and Health (ICF) framework. Subsequently, the clinimetric quality of identified PROMs was evaluated. The literature search identified 144 papers that met the inclusion criteria, and nine frequently used PROMs were identified. These covered 29 ICF outcome domains, which could be grouped into three of the four main ICF chapters: body function (n = 7), activity and participation (n = 19), environmental factors (n = 3), and body structure (n = 0). A low quantity (n = 3) of papers was identified that studied the clinimetric quality of PROMs. The Scoliosis Research Society (SRS)-22 has the highest level of clinimetric quality for ASD. Outcome domains related to mobility and pain were well represented. We identified a gap in current outcome measures regarding neurological and pulmonary function. In addition, no outcome domains were measured in the ICF chapter body structure. These results will serve as a foundation for the process of seeking international consensus on a standard set of outcome domains, accompanied PROMs and contributing factors to be used in future clinical trials and spine registries.

  4. The influence of intention and outcome on evaluations of social interaction.

    Science.gov (United States)

    Wu, Xiaoying; Hua, Rui; Yang, Zhangxiang; Yin, Jun

    2018-01-01

    Reading and making sense of social interactions between individuals is an important part of our daily social lives. Given that actions tend to be interpreted in terms of intent within the observed outcome, we investigated how intent and outcome interactively influence evaluations of social interactions. Through visual animations, intent was operationalized as an agent's (i.e., actor's) act intentionally or unintentionally having an influence on another agent (i.e., affectee). In Experiment 1, the act was helpful and the consequences brought small or great benefits to the affectee. In Experiment 2, the act was harmful and brought small or great losses to the affectee. We found that for both helpful and harmful contexts, social interaction evaluations were influenced by an interaction between the intent and outcome of the act. Specifically, great help/harm (i.e., the great-benefits or great-losses condition) was rated as a stronger social interaction than small help/harm, and the difference was larger in the intentional condition than in the unintentional condition. Furthermore, regardless of the interaction valence, the effect of the intent was larger than the effect of the outcome when evaluating social interaction. This result suggests that observers consider the intent and outcome jointly when evaluating a given social interaction, and the intent has a privileged role in this process. These findings are consistent with the idea that the intent is often deemed to be the cause driving the effect of outcome, and they help us to understand how social interactions are constructed within the action understanding system. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Papain-based gel for biochemical caries removal: influence on microtensile bond strength to dentin

    Directory of Open Access Journals (Sweden)

    Evandro Piva

    2008-12-01

    Full Text Available This study investigated the influence of a papain-based gel (Papacárie for chemo-mechanical caries removal on bond strength to dentin. Human molars were assigned to the following groups: Group 1: sound teeth were flattened to expose dentin; Group 2: after flattening of surfaces, the papain-based gel was applied on the sound dentin; Group 3: overlying enamel from carious teeth was removed and mechanical excavation of dentin was conducted; Group 4: chemo-mechanical excavation of carious dentin was conducted using the papain-based gel. The Prime&Bond NT or Clearfil SE Bond adhesive systems were used for restorative procedures. A microtensile bond strength test was performed, and the modes of failure were determined under SEM. The data were submitted to two-way ANOVA and Tukey's test (p < 0.05. No significant differences were observed between the sound dentin groups. For both excavation methods, Clearfil presented a significantly higher bond strength than Prime&Bond NT. Also, for Clearfil, the mechanically excavated samples disclosed a significantly higher bond strength than the chemo-mechanically ones. For Prime&Bond NT, no significant differences were detected between the excavation methods. Predominance of mixed failures for the sound substrate and of adhesive failures for the carious dentin one was detected. The bond strength to carious dentin of the self-etching system was negatively affected by chemo-mechanical excavation using the papain-based gel.

  6. Positive Outcome Expectancy Mediates the Relationship Between Peer Influence and Internet Gaming Addiction Among Adolescents in Taiwan.

    Science.gov (United States)

    Wu, Jo Yung Wei; Ko, Huei-Chen; Wong, Tsui-Yin; Wu, Li-An; Oei, Tian Po

    2016-01-01

    The present study examined the role of positive outcome expectancy in the relationship between peer/parental influence and Internet gaming addiction (IGA) among adolescents in Taiwan. Two thousand, one hundred and four junior high students completed the Chen Internet Addiction Scale for IGA, Parental Influence for IGA, peer influence for IGA, and Positive Outcome Expectancy of Internet Gaming Questionnaire. Results showed that the three types of peer influences (positive attitudes toward Internet gaming, frequency of Internet game use, and invitation to play) and positive outcome expectancy were significantly and positively correlated with IGA. Moreover, peer influence was also positively correlated with positive outcome expectancy. On the other hand, positive outcome expectancy and parental influences had a low correlation. Structural equation modeling analysis revealed that positive outcome expectancy did not mediate the relationship between either type of parental influences and IGA, and only the parent's invitation to play Internet games directly predicted IGA severity. However, peers' positive attitude or the frequency of peers' Internet game use positively predicted IGA and was fully mediated through positive outcome expectancy of Internet gaming. In addition, the frequency of peers' invitation to play Internet games directly and indirectly predicted IGA severity through a partial mediation of positive outcome expectancy of Internet gaming. The overall fit of the model was adequate and was able to explain 25.0 percent of the variance. The findings provide evidence in illuminating the role of peer influences and positive outcome expectancy of Internet gaming in the process of why adolescents may develop IGA.

  7. Experimental investigation of the factors influencing the polymer-polymer bond strength during two component injection moulding

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2007-01-01

    Two component injection moulding is a commercially important manufacturing process and a key technology for Moulded Interconnect Devices (MIDs). Many fascinating applications of two component or multi component polymer parts are restricted due to the weak interfacial adhesion of the polymers...... effectively control the adhesion between two polymers. The effects of environmental conditions on the bond strength after moulding are also investigated. The material selections and environmental conditions were chosen based on the suitability of MID production, but the results and discussion presented....... A thorough understanding of the factors that influence the bond strength of polymers is necessary for multi component polymer processing. This paper investigates the effects of the process and material parameters on the bond strength of two component polymer parts and identifies the factors which can...

  8. Experimental investigation of the factors influencing the polymer-polymer bond strength during two-component injection moulding

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Bondo, Martin

    2010-01-01

    Two-component injection moulding is a commercially important manufacturing process and a key technology for combining different material properties in a single plastic product. It is also one of most industrially adaptive process chain for manufacturing so-called moulded interconnect devices (MIDs......). Many fascinating applications of two-component or multi-component polymer parts are restricted due to the weak interfacial adhesion of the polymers. A thorough understanding of the factors that influence the bond strength of polymers is necessary for multi-component polymer processing. This paper...... investigates the effects of the process conditions and geometrical factors on the bond strength of two-component polymer parts and identifies the factors which can effectively control the adhesion between two polymers. The effects of environmental conditions on the bond strength are also investigated...

  9. Influence of enamel conditioning on the shear bond strength of different adhesives.

    Science.gov (United States)

    Brauchli, Lorenz; Muscillo, Teodoro; Steineck, Markus; Wichelhaus, Andrea

    2010-11-01

    Phosphoric acid etching is the gold standard for enamel conditioning. However, it is possible that air abrasion or a combination of air abrasion and etching might result in enhanced adhesion. The aim of this study was to investigate the effect of different enamel conditioning methods on the bond strength of six adhesives. Three different enamel conditioning procedures (phosphoric acid etching, air abrasion, air abrasion + phosphoric acid etching) were evaluated for their influence on the shear bond strength of six different adhesives (Transbond™ XT, Cool-Bond™, Fuji Ortho LC, Ultra Band-Lok, Tetric(®) Flow, Light-Bond™). Each group consisted of 15 specimens. Shear forces were measured with a universal testing machine. The scores of the Adhesive Remnant Index (ARI) were also analyzed. There were no significant differences between phosphoric acid etching and air abrasion + phosphoric acid etching. Air abrasion as a single conditioning technique led to significantly lower shear forces. The ARI scores did not correlate with the shear strengths measured. There were greater variations in shear forces for the different adhesives than for the conditioning techniques. The highest shear forces were found for the conventional composites Transbond™ XT and Cool- Bond™ in combination with conventional etching. Air abrasion alone and in combination with phosphoric acid etching showed no advantages compared with phosphoric acid etching alone and, therefore, cannot be recommended.

  10. Factors influencing the use of outcome measures in physical therapy practice.

    Science.gov (United States)

    Wedge, Frances M; Braswell-Christy, Jennifer; Brown, Cynthia J; Foley, Kathleen T; Graham, Cecilia; Shaw, Sharon

    2012-02-01

    Use of outcome measures in physical therapy practice is central to evaluating the effectiveness of treatment interventions, providing accountability and addressing quality of physical therapy programs. There is limited discussion on barriers and facilitators to using outcome measures in physical therapy practice. The purpose of this study was to identify factors that influence a physical therapist when deciding to use outcome measures in clinical practice. Participants were 21 physical therapists, seven each from skilled nursing facilities, outpatient clinics, and inpatient rehabilitation facilities. A grounded theory approach was used for interview and data collection. Common themes were determined from the data and a theory developed to explain the rationale behind physical therapists' decisions to use or not use outcome measures in clinical practice. Three overlapping themes related to (1) concepts of time, (2) knowledge, and (3) facility culture were indentified as factors influencing the use of outcome measures. A fourth encompassing theme, professionalism, identified the value placed on the use of outcome measures in practice. Data revealed that therapists require more information on the outcome measures available, and this information needs to be easily accessible within the workplace. Therapists value information generated by using outcome measures in the clinical setting, but need information on what measures are available and psychometric properties. Information must be easily accessible and measures easy to use. Newer graduates and recent learners have a foundation in the use of outcome measures, but more needs to be done in the clinic and through continuing education to promote increased use and understanding.

  11. The influence of water removal on the strength and toughness of cortical bone

    OpenAIRE

    Nyman, Jeffry S.; Roy, Anuradha; Shen, Xinmei; Acuna, Rae L.; Tyler, Jerrod H.; Wang, Xiaodu

    2006-01-01

    Although the effects of dehydration on the mechanical behavior of cortical bone are known, the underlying mechanisms for such effects are not clear. We hypothesize that the interactions of water with the collagen and mineral phases each have a unique influence on mechanical behavior. To study this, strength, toughness, and stiffness were measured with three-point bend specimens made from the mid-diaphysis of human cadaveric femurs and divided into six test groups: control (hydrated), drying i...

  12. The Influence of Negligence, Intention, and Outcome on Children's Moral Judgments

    Science.gov (United States)

    Nobes, Gavin; Panagiotaki, Georgia.; Pawson, Chris

    2009-01-01

    Piaget (1932) and subsequent researchers have reported that young children's moral judgments are based more on the outcomes of actions than on the agents' intentions. The current study investigated whether negligence might also influence these judgments and explain children's apparent focus on outcome. Children (3-8 years of age) and adults (N =…

  13. Influence of Curing Age and Mix Composition on Compressive Strength of Volcanic Ash Blended Cement Laterized Concrete

    Directory of Open Access Journals (Sweden)

    Babafemi A.J.

    2012-01-01

    Full Text Available This study investigates the influence of curing age and mix proportions on the compressive strength of volcanic ash (VA blended cement laterized concrete. A total of 288 cubes of 100mm dimensions were cast and cured in water for 3, 7, 28, 56, 90 and 120 days of hydration with cement replacement by VA and sand replacement by laterite both ranging from 0 to 30% respectively while a control mix of 28-day target strength of 25N/mm2 (using British Method was adopted. The results show that the compressive strength of the VA-blended cement laterized concrete increased with the increase in curing age but decreased as the VA and laterite (LAT contents increased. The optimum replacement level was 20%LAT/20%VA. At this level the compressive strength increased with curing age at a decreasing rate beyond 28 days. The target compressive strength of 25N/mm2 was achieved for this mixture at 90 days of curing. VA content and curing age was noted to have significant effect (α ≤ 0.5 on the compressive strength of the VA-blended cement laterized concrete.

  14. The influence of caffeine ingestion on strength and power performance in female team-sport players.

    Science.gov (United States)

    Ali, Ajmol; O'Donnell, Jemma; Foskett, Andrew; Rutherfurd-Markwick, Kay

    2016-01-01

    The aim of this study was to examine the influence of caffeine supplementation on knee flexor and knee extensor strength before, during and after intermittent running exercise in female team-sport players taking oral contraceptive steroids (OCS). Ten healthy females (24 ± 4 years; 59.7 ± 3.5 kg; undertaking 2-6 training sessions per week) taking low-dose monophasic oral contraceptives of the same hormonal composition took part in a randomised, double-blind, placebo-controlled crossover-design trial. Sixty minutes following the ingestion of a capsule containing 6 mg∙kg -1 body mass anhydrous caffeine or artificial sweetener (placebo), participants completed a 90-min intermittent treadmill-running protocol. Isometric strength performance and eccentric and concentric strength and power of the knee flexors and knee extensors (using isokinetic dynamometer), as well as countermovement jump (CMJ), was measured before, during and after the exercise protocol, as well as ~12 h post-exercise. Blood samples were taken before, during and post-exercise to measure glucose, insulin and free fatty acids (FFA). Caffeine supplementation significantly increased eccentric strength of the knee flexors ( P  performance. FFA was elevated with caffeine supplementation over time ( P  caffeine intake. Caffeine supplementation increased eccentric strength and power in female team-sport players taking OCS both during an intermittent running protocol and the following morning.

  15. Influence of Cryotherapy on muscle strength: A Literaturae Review

    Directory of Open Access Journals (Sweden)

    Gilvaney Gomes Pereira

    2013-01-01

    Full Text Available The objective of this study was to verify the behavior of muscle strength before cryotherapy use through a literature review. To write this review it was performed the analysis of works with descriptive-analytical approach about the interference of cryotherapy in the muscle strength, and the total of the studies collected was 15. After analysis of collected studies of scientific sources it was verified that there were controversies in the researches found about the muscle strength increased or reduction. It is necessary to conduct new studies that will elucidate physiological effects of ice on the muscle strength.

  16. INFLUENCE OF CRYOTHERAPY ON MUSCLE STRENGTH: A LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    Gilvaney Gomes Pereira

    2013-01-01

    Full Text Available The objective of this study was to verify the behavior of muscle strength before cryotherapy use through a literature review. To write this review it was performed the analysis of works with descriptive-analytical approach about the interference of cryotherapy in the muscle strength, and the total of the studies collected was 15. After analysis of collected studies of scientific sources it was verified that there were controversies in the researches found about the muscle strength increased or reduction. It is necessary to conduct new studies that will elucidate physiological effects of ice on the muscle strength.

  17. Survival and Injury Outcome After TBI: Influence of Pre- and Post-Exposure to Caffeine

    Science.gov (United States)

    2012-10-01

    10-1-0757 TITLE: Survival and Injury Outcome After TBI: Influence of Pre- and Post- Exposure to Caffeine PRINCIPAL INVESTIGATOR...Lusardi, Ph.D. Survival and Injury Outcome After TBI: Influence of Pre- and Post- Exposure to Caffeine 33 Legacy Emanual Hospital & Health Center...Phase 1: Study the prophylactic effects of caffeine exposure prior to FPI

  18. The Influences of Iron Ore Tailings as Fine Aggregate on the Strength of Ultra-High Performance Concrete

    Directory of Open Access Journals (Sweden)

    Zhigang Zhu

    2015-01-01

    Full Text Available The present study looks for the feasibility of preparing UHPC with iron ore tailings (IOT for short as fine aggregate. To enhance outstanding high performances, some influences on UHPC mortars were investigated such as different kinds of sands, different mix ratio of sands, and different largest particle size of fine aggregate. The results show that IOT have negligible poorer aggregate performance than silica sands but better than river sands. The strength of UHPC reaches the highest point when silica sands were instead 60% by IOT. As the largest particle size of fine aggregate is decreasing, the strength and frost resistance of UHPC were improved, but the liquidity was decreased. Micropowder of IOT affects the strength and the optimal content was 4%.

  19. THE INFLUENCE OF HIP STRENGTH ON KNEE KINEMATICS DURING A SINGLE-LEGGED MEDIAL DROP LANDING AMONG COMPETITIVE COLLEGIATE BASKETBALL PLAYERS.

    Science.gov (United States)

    Suzuki, Hidetomo; Omori, Go; Uematsu, Daisuke; Nishino, Katsutoshi; Endo, Naoto

    2015-10-01

    A smaller knee flexion angle and larger knee valgus angle during weight-bearing activities have been identified as risk factors for non-contact anterior cruciate ligament (ACL) injuries. To prevent such injuries, attention has been focused on the role of hip strength in knee motion control. However, gender differences in the relationship between hip strength and knee kinematics during weight-bearing activities in the frontal plane have not been evaluated. The purpose of this study was to determine the influence of hip strength on knee kinematics in both genders during a single-legged landing task in the frontal plane. The hypotheses were that 1) subjects with a greater hip strength would demonstrate larger knee flexion and smaller knee valgus and internal rotation angles and 2) no gender differences would exist during the single-legged landing task. Forty-three Japanese collegiate basketball players (20 males, 23 females) participated in this study. Three-dimensional motion analysis was used to evaluate knee kinematics during a single-legged medial drop landing (SML). A hand-held dynamometer was used to assess hip extensor (HEXT), abductor (HAB), and external rotator (in two positions: seated position [SHER] and prone [PHER]) isometric strength. Spearman rank correlation coefficients (ρ) were determined for correlations between hip strength and knee kinematics at initial contact (IC) and peak (PK) during SML (p genders. Hip strength may, therefore, play an important role in knee motion control during sports activities, suggesting that increased hip strength may help to prevent non-contact ACL injuries in athletes of both genders. Moreover, gender-specific programs may be needed to control abnormal knee motion, as the influence of hip strength on knee kinematics may differ based on gender. 3.

  20. Influence of the supporting die structures on the fracture strength of all-ceramic materials.

    Science.gov (United States)

    Yucel, Munir Tolga; Yondem, Isa; Aykent, Filiz; Eraslan, Oğuz

    2012-08-01

    This study investigated the influence of the elastic modulus of supporting dies on the fracture strengths of all-ceramic materials used in dental crowns. Four different types of supporting die materials (dentin, epoxy resin, brass, and stainless steel) (24 per group) were prepared using a milling machine to simulate a mandibular molar all-ceramic core preparation. A total number of 96 zirconia cores were fabricated using a CAD/CAM system. The specimens were divided into two groups. In the first group, cores were cemented to substructures using a dual-cure resin cement. In the second group, cores were not cemented to the supporting dies. The specimens were loaded using a universal testing machine at a crosshead speed of 0.5 mm/min until fracture occurred. Data were statistically analyzed using two-way analysis of variance and Tukey HSD tests (α = 0.05). The geometric models of cores and supporting die materials were developed using finite element method to obtain the stress distribution of the forces. Cemented groups showed statistically higher fracture strength values than non-cemented groups. While ceramic cores on stainless steel dies showed the highest fracture strength values, ceramic cores on dentin dies showed the lowest fracture strength values among the groups. The elastic modulus of the supporting die structure is a significant factor in determining the fracture resistance of all-ceramic crowns. Using supporting die structures that have a low elastic modulus may be suitable for fracture strength tests, in order to accurately reflect clinical conditions.

  1. Bond strength to dentin with artificial carious lesions: influence of caries detecting dye.

    Science.gov (United States)

    Palma, R G; Turbino, M L; Matson, E; Powers, J M

    1998-06-01

    To evaluate the influence of dyes for caries detection on tensile bond strength of adhesive materials to artificial carious dentin. Buccal and lingual enamel of human molars were removed leaving intact dentin surfaces. The entire surface of each specimen was covered with nail varnish, keeping a window area of 4 x 4 mm. Artificial carious lesions were induced with acidified gel. Three dyes (0.5% basic fuchsin; Caries Finder and Cari-D-Tect) were used according to manufacturers' recommendations. Specimens were etched with 35% phosphoric acid for 20 s, washed and dried, leaving a wet dentin surface. The adhesive system (Prime & Bond 2.0) was applied in two layers and light-cured. Restorative materials (TPH Spectrum, Dyract, Advance) were bonded using a 3-mm diameter inverted-cone mold. Control groups were made without dye. Eight samples were tested for each group. After 24 hrs of storage in distilled water, the samples were debonded using a testing machine at 0.5 mm/min crosshead speed. ANOVA and Tukey-Kramer test showed that TPH Spectrum (0.73 MPa) and Dyract (0.74 MPa) had similar bond strengths, and both were higher than Advance (0.0 MPa), which was statistically different (P strength for any tested materials.

  2. Influence of the number of cycles on shear fatigue strength of resin composite bonded to enamel and dentin using dental adhesives in self-etching mode.

    Science.gov (United States)

    Tsujimoto, Akimasa; Barkmeier, Wayne W; Erickson, Robert L; Takamizawa, Toshiki; Latta, Mark A; Miyazaki, Masashi

    2018-01-30

    The influence of the number of cycles on shear fatigue strength to enamel and dentin using dental adhesives in self-etch mode was investigated. A two-step self-etch adhesive and two universal adhesives were used to bond to enamel and dentin in self-etch mode. Initial shear bond strength and shear fatigue strength to enamel and dentin using the adhesive in self-etch mode were determined. Fatigue testing was used with 20 Hz frequency and cycling periods of 50,000, 100,000 and 1,000,000 cycles, or until failure occurred. For each of the cycling periods, there was no significant difference in shear fatigue strength across the cycling periods for the individual adhesives. Differences in shear fatigue strength were found between the adhesives within the cycling periods. Regardless of the adhesive used in self-etch mode for bonding to enamel or dentin, shear fatigue strength was not influenced by the number of cycles used for shear fatigue strength testing.

  3. [Chlorine coatings on skin surfaces. II. Parameters influencing the coating strength].

    Science.gov (United States)

    Gottardi, W; Karl, A

    1991-05-01

    Although active chlorine compounds have been used for more than 140 years (Semmelweis, 1848) as a skin disinfectant the phenomenon of the "chlorine covers" not earlier than 1988 has been described for the first time (Hyg. + Med. 13 (1988) 157). It deals with a chemical alteration of the uppermost skin layer which comes apparent in an oxydizing action against aqueous iodide. Its origin is chlorine covalently bound in the form of N-Cl functions to the protein matrix of the horny skin. Since the chlorine covers exhibit a persistant disinfecting activity which might be important for practice, the factors influencing their strength have been established. The most important are: the kind of the chlorine system, the concentration (oxydation capacity), pH, temperature and the volume of the used solution, the time of action, the application technique and the state of the skin. Variations of the latter can be observed at different skin areas of one and the same person as well as at the same areas of different persons, and result in differences of the cover strength up to 100%. The stability on dry skin is very good, showing a decomposition rate of approximately 1.2% per hour. However on skin surfaces moistened by sweat (e.g. hands covered by surgeons gloves) the chlorine cover is disingrated much more faster (decomposition rate: 40-50% per hour). Washing with soap as well as the action of alcohols cause virtually no decrease in the cover strength, while wetting by solutions of reducing agents (e.g. thiosulfate, cysteine, iodide) provokes a fast decomposition suitable for removing the chlorine covers.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Cooperative context is a determinant of the social influence on outcome evaluation: An electrophysiological study.

    Science.gov (United States)

    Kimura, Kenta; Katayama, Jun'ichi

    2016-02-01

    The present study examined whether or not a cooperative context is a determinant of the social influence on the evaluation of two action outcomes: a monetary outcome and a conflict of opinion with other group members. In the present study, three-person groups were randomly assigned to be either a cooperative or individual group and asked to perform a gambling task. The monetary outcomes in the cooperative group were interrelated among group members, whereas those in the individual group did not influence each other. The present results showed that monetary outcomes elicited feedback-related negativity (FRN) and a conflict of opinion with other group members elicited FRN-like negativity, which reflect an evaluation of the motivational significance of action outcomes. The FRN elicited by monetary outcomes was reduced when participants shared decisions with other group members only in the cooperative group, indicating that the cooperative context reduced the motivational significance of monetary outcomes through the diffusion of responsibility. The FRN-like negativity elicited by a conflict of opinion showed a different pattern between the cooperative and individual groups, indicating that the cooperative context can influence the evaluation of a conflict of opinion, possibly via the modulation of group cohesiveness or conflict processing. The present results suggest that a cooperative context, rather than the social setting, is a determinant of the social influence on outcome evaluation. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Essential Factors Influencing the Bonding Strength of Cold-Sprayed Aluminum Coatings on Ceramic Substrates

    Science.gov (United States)

    Drehmann, R.; Grund, T.; Lampke, T.; Wielage, B.; Wüstefeld, C.; Motylenko, M.; Rafaja, D.

    2018-02-01

    The present work summarizes the most important results of a research project dealing with the comprehensive investigation of the bonding mechanisms between cold-sprayed Al coatings and various poly- and monocrystalline ceramic substrates (Al2O3, AlN, Si3N4, SiC, MgF2). Due to their exceptional combination of properties, metallized ceramics are gaining more and more importance for a wide variety of applications, especially in electronic engineering. Cold spray provides a quick, flexible, and cost-effective one-step process to apply metallic coatings on ceramic surfaces. However, since most of the existing cold-spray-related publications focus on metallic substrates, only very little is known about the bonding mechanisms acting between cold-sprayed metals and ceramic substrates. In this paper, the essential factors influencing the bonding strength in such composites are identified. Besides mechanical tensile strength testing, a thorough analysis of the coatings and especially the metal/ceramic interfaces was conducted by means of HRTEM, FFT, STEM, EDX, EELS, GAXRD, and EBSD. The influence of substrate material, substrate temperature, and particle size is evaluated. The results suggest that, apart from mechanical interlocking, the adhesion of cold-sprayed metallic coatings on ceramics is based on a complex interplay of different mechanisms such as quasiadiabatic shearing, static recrystallization, and heteroepitaxial growth.

  6. Hormone Replacement and Strength Training Positively Influence Balance During Gait in Post-Menopausal Females: A Pilot Study

    Science.gov (United States)

    Perry, Stephen D.; Bombardier, Eric; Radtke, Alison; Tiidus, Peter M.

    2005-01-01

    This study examined the effects of hormone replacement combined with strength training on improving dynamic balance control in post-menopausal women. Thirty one participating post-menopausal women were divided into three groups (hormone replacement (HR), non-hormone replacement (NR) and control (CR) group). HR and NR groups were tested for muscle strength and balance control during gait, prior to training and following a six week lower body strength training program. Quadriceps muscle strength was evaluated as isokinetic peak torque (60°·sec-1) using a CYBEX NORM and balance control was evaluated by center of mass - base of support relationships and ground reaction forces during gait perturbations. Only the HR group showed significantly (p < 0.05) improved balance control during the initial phase of unexpected gait termination and single stance periods while walking across uneven terrain following training. The strength gains in the HR group tended to be greater than in the NR group over the six week training program, although neither group showed statistically significant increases. The CR group showed no significant differences between testing times. HR in post-menopausal females may enhance dynamic balance control when combined with a strength training program, even if no statistically significant gains in strength are achieved. Key Points This study provides evidence that even a short modest strength training program can enhance dynamic balance control in older adult females taking hormone replacement. If potential benefits of hormone replacement therapy extend to enhancing muscle strength then this would be important in designing optimal interventions for both strength and balance for this cohort. Future work should explore the influence of hormone replacement therapy on other dynamic balance or functional tasks. PMID:24501551

  7. Importance of tie strengths in the prisoner's dilemma game on social networks

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Bo, E-mail: xubosuper@163.com [Department of Information Systems, School of Economics and Management, Beihang University (China); Liu, Lu; You, Weijia [Department of Information Systems, School of Economics and Management, Beihang University (China)

    2011-06-13

    Though numerous researches have shown that tie strengths play a key role in the formation of collective behavior in social networks, little work has been done to explore their impact on the outcome of evolutionary games. In this Letter, we studied the effect of tie strength in the dynamics of evolutionary prisoner's dilemma games by using online social network datasets. The results show that the fraction of cooperators has a non-trivial dependence on tie strength. Weak ties, just like previous researches on epidemics and information diffusion have shown, play a key role by the maintenance of cooperators in evolutionary prisoner's dilemma games. -- Highlights: → Tie strength is used to measure heterogeneous influences of different pairs of nodes. → Weak ties play a role in maintaining cooperation in prisoner's dilemma games. → Micro-dynamics of nodes are illustrated to explain the conclusion.

  8. The influence of radiotherapy on cosmetic outcome after breast conservative surgery

    International Nuclear Information System (INIS)

    McCormick, Beryl; Sacchini, Virgilio; Luini, Alberto; Agresti, Roberto; Greco, Marco; Manzari, Antonella; Mariani, Luigi; Zucali, Roberto

    1995-01-01

    Purpose: The influence of radiotherapy in the cosmetic outcome after conservative surgery for breast cancer was evaluated using an objective method of calculating the asymmetry between the two breasts. Methods and Materials: One hundred and one patients treated with the same conservative surgery were evaluated for cosmetic outcome. Sixty-one of them received external radiotherapy (50 + 10 Gy) to the residual breast; the remaining 40 underwent surgery only. The aspect of the patients' breasts was objectively assessed for symmetry by means of a computerized technique. A subjective assessment of the cosmetic outcome was performed both by physician and patient. These objective and subjective assessments were compared in the two groups treated with or without radiotherapy. Results: The results obtained did not show significant differences in terms of cosmetic outcome in the two groups. Skin telangectasia was noted in two radiotherapy patients, while hypertrophic breast scars were only noted in six nonirradiated patients. Conclusions: We found that standard radiotherapy does not seem to influence the symmetry and the cosmetic results in breast conservative treatment when compared to a similar group of patients with the same quadrantectomy procedure and no radiotherapy

  9. Genetic and Environmental Influences on Pulmonary Function and Muscle Strength: The Chinese Twin Study of Aging

    DEFF Research Database (Denmark)

    Tian, Xiaocao; Xu, Chunsheng; Wu, Yili

    2017-01-01

    Genetic and environmental influences on predictors of decline in daily functioning, including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), handgrip, and five-times-sit-to-stand test (FTSST), have not been addressed in the aging Chinese population. We performed classical twin...... was moderate for FEV1, handgrip, and FTSST (55-60%) but insignificant for FVC. Only FVC showed moderate control, with shared environmental factors accounting for about 50% of the total variance. In contrast, all measures of pulmonary function and muscle strength showed modest influences from the unique...

  10. 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.

  11. Effect of low appendicular lean mass, grip strength, and gait speed on the functional outcome after surgery for distal radius fractures.

    Science.gov (United States)

    Roh, Young Hak; Noh, Jung Ho; Gong, Hyun Sik; Baek, Goo Hyun

    2017-12-01

    Patients with low appendicular lean mass plus slow gait speed or weak grip strength are at risk for poor functional recovery after surgery for distal radius fracture, even when they have similar radiologic outcomes. Loss of skeletal muscle mass and consequent loss in muscle function associate with aging, and this condition negatively impacts the activities of daily living and increases elderly individuals' frailty to falls. Thus, patients with low appendicular lean mass would show different functional recovery compared to those without this condition after surgery for distal radius fracture (DRF). This study compares the functional outcomes after surgery for DRF in patients with or without low appendicular lean mass plus slowness or weakness. A total of 157 patients older than 50 years of age with a DRF treated via volar plate fixation were enrolled in this prospective study. A definition of low appendicular lean mass with slowness or weakness was based on the consensus of the Asian Working Group for Sarcopenia. The researchers compared functional assessments (wrist range of motion and Michigan Hand Questionnaire [MHQ]) and radiographic assessments (radial inclination, volar tilt, ulnar variance, and articular congruity) 12 months after surgery between patients with and without low appendicular lean mass plus slowness or weakness. Multivariable regression analyses were performed to determine whether appendicular lean mass, grip strength, gait speed, patient demographic, or injury characteristics accounted for the functional outcomes. Patients with low appendicular lean mass plus slowness or weakness showed a significantly lower recovery of MHQ score than those in the control group throughout 12 months. There was no significant difference in the range of motion between the groups. The radiologic outcomes showed no significant difference between groups in terms of volar tilt, radial inclination, or ulnar variance. According to multivariable regression analysis

  12. 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)

  13. Changes in the flexural strength of engineering ceramics after high temperature sodium corrosion test. Influence after sodium exposure for 1000 hours

    International Nuclear Information System (INIS)

    Hayashi, Kazunori; Tachi, Yoshiaki; Kano, Shigeki; Hirakawa, Yasushi; Komine, Ryuji; Yoshida, Eiichi

    1998-02-01

    Engineering ceramics have excellent properties such as high strength, high hardness and high heat resistance compared with metallic materials. To apply the ceramic in fast reactor environment, it is necessary to evaluate the sodium compatibility and the influence of sodium on the mechanical properties of ceramics. In this study, the influence of high temperature sodium on the mechanical properties of sintered ceramics of conventional and high purity Al 2 O 3 , SiC, SiAlON, AlN and unidirectional solidified ceramics of Al 2 O 3 /YAG eutectic composite were investigated by means of flexure tests. Test specimens were exposed in liquid sodium at 823K and 923K for 3.6Ms. There were no changes in the flexural strength of the conventional and high purity Al 2 O 3 , AlN and Al 2 O 3 /YAG eutectic composite after the sodium exposure at 823K. On the contrary, the decrease in the flexural strength was observed in SiC and SiAlON. After the sodium exposure at 923K, there were also no changes in the flexural strength of AlN and Al 2 O 3 /YAG eutectic composite. In the conventional and high purity Al 2 O 3 and SiC, the flexural strength decreased and signs of grain boundary corrosion were detected by surface observation. The flexural strength of SiAlON after the sodium exposure at 923K increased instead of severe corrosion. In the specimens those showed no changes in the flexural strength, further exposure in sodium is needed to verify whether the mechanical properties degrade or not. For SiAlON, it is necessary to clarify the reason for the increased strength after the sodium exposure at 923K. (author)

  14. Clinico-pathological factors influencing surgical outcome in drug resistant epilepsy secondary to mesial temporal sclerosis.

    Science.gov (United States)

    Savitr Sastri, B V; Arivazhagan, A; Sinha, Sanjib; Mahadevan, Anita; Bharath, R D; Saini, J; Jamuna, R; Kumar, J Keshav; Rao, S L; Chandramouli, B A; Shankar, S K; Satishchandra, P

    2014-05-15

    Mesial temporal sclerosis (MTS) is the most common cause of drug resistant epilepsy amenable for surgical treatment and seizure control. This study analyzed the outcome of patients with MTS following anterior temporal lobectomy and amygdalohippocampectomy (ATL-AH) over 10 years and correlated the electrophysiological and radiological factors with the post operative seizure outcome. Eighty seven patients were included in the study. Sixty seven (77.2%) patients had an Engel Class 1 outcome, 9 (11.4%) had Class 2 outcome. Engel's class 1 outcome was achieved in 89.9% at 1 year, while it reduced slightly to 81.9% at 2 years and 76.2% at 5 year follow up. Seventy seven (88.5%) patients had evidence of hippocampal sclerosis on histopathology. Dual pathology was observed in 19 of 77 specimens with hippocampal sclerosis, but did not influence the outcome. Factors associated with an unfavorable outcome included male gender (p=0.04), and a higher frequency of pre-operative seizures (p=0.005), whereas the presence of febrile seizures (p=0.048) and loss of hippocampal neurons in CA4 region on histopathology (p=0.040) were associated with favorable outcome. The effect of CA4 loss on outcome is probably influenced by neuronal loss in other subfields as well since isolated CA4 loss was rare. Abnormal post operative EEG at the end of 1 week was found to be a significant factor predicting unfavorable outcome (p=0.005). On multivariate analysis, the pre-operative seizure frequency was the only significant factor affecting outcome. The present study observed excellent seizure free outcome in a carefully selected cohort of patients with MTS with refractory epilepsy. The presence of dual pathology did not influence the outcome. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. A comprehensive study on the influence of strength and stiffness eccentricities to the on-plan rotation of asymmetric structure

    Science.gov (United States)

    Rashidi, Azida; Majid, Taksiah A.; Fadzli, M. N.; Faisal, Ade; Noor, Suhaila M.

    2017-10-01

    All buildings are subjected to some degree of torsion which in turn changes the member torsional demands from that of translation only. Torsional effects on buildings subjected to earthquakes are not found directly in structural analysis unless full three-dimensional inelastic dynamic time history analysis is conducted. Since design is often conducted using two-dimensional analysis, these effects are not directly considered. There is currently an understanding on how different factors may influence torsion, however, the degree to which these factors influence torsion is relatively unknown. Slab rotation effect is considered a major response parameter to represent the severity of the torsional response of eccentric systems; hence, it is considered in this study. The centre of strength (CR) and centre of stiffness (CS) are the two main factors under considerations. A comprehensive analysis on eighty different CR and CS conditions are applied to a three-dimensional, asymmetric building and their influences to slab rotation are observed. The CR/CS conditions are applied by varying strength eccentricities (er) and stiffness eccentricities (es) using two condition models. Then, earthquake ground motions are applied in z-direction under elastic and inelastic conditions. The results interpreted using a simple approach shows important slab rotation behaviour that forms interesting findings from this study. The slab rotation demand is found to reduce as strength eccentricity moves away from the Centre of Mass (CoM) but is independent of the stiffness eccentricity. The study also confirms finding of previous works which states that stiffness eccentricity plays a minor role when assessing the torsional behaviour of a ductile systems. Results from inelastic analysis shows slab rotation demand increases as strength eccentricity is closer to the CoM but it remains constant for elastic analysis.

  16. The influence of salivary contamination on shear bond strength of dentin adhesive systems.

    Science.gov (United States)

    Park, Jeong-won; Lee, Kyung Chae

    2004-01-01

    This study evaluated the influence of salivary contamination during dentin bonding procedures on shear bond strength and investigated the effect of contaminant-removing treatments on the recovery of bond strength for two dentin bonding agents. One hundred and ten human molars were embedded in cylindrical molds with self-curing acrylic resin. The occlusal dentin surface was exposed by wet grinding with #800 silicon carbide abrasive paper. The teeth were divided into five groups for One-step (OS) (BISCO, Inc) and six groups for Clearfil SE Bond (SE) (Kuraray Co, Ltd, Osaka, Japan). For One-step, the grinding surface was treated with 32% phosphoric acid; BAC (BISCO Inc) and divided into five groups: OS control group (uncontaminated), OS I (salivary contamination, blot dried), OS II (salivary contamination, completely dried), OS III (salivary contamination, wash and blot dried) and OS IV (salivary contamination, re-etching for 10 seconds, wash and blot dried). For SE bond, the following surface treatments were done: SE control group (primer applied to the fresh dentin surface), SE I (after salivary contamination, primer applied), SE II (primer, salivary contamination, dried), SE III (primer, salivary contamination, wash and dried), SE IV (after procedure of SE II, re-application of primer) and SE V (after procedure of SE III, re-application of primer). Each bonding agent was applied and light cured for 10 seconds. Clearfil AP-X (Kuraray Co, Ltd) composite was packed into the Ultradent mount jig mold and light cured for 40 seconds. The bonded specimens were stored for 24 hours in a 37 degrees C waterbath. The shear bond strengths were measured using an Instron testing machine (Model 4202, Instron Corp). The data for each group were subjected to one-way ANOVA followed by the Newman-Keuls test to make comparisons among the groups. The results were as follows: In the One-step groups, the OS II group showed statistically significant lower shear bond strength than the OS

  17. Influence of warm air-drying on enamel bond strength and surface free-energy of self-etch adhesives.

    Science.gov (United States)

    Shiratsuchi, Koji; Tsujimoto, Akimasa; Takamizawa, Toshiki; Furuichi, Tetsuya; Tsubota, Keishi; Kurokawa, Hiroyasu; Miyazaki, Masashi

    2013-08-01

    We examined the effect of warm air-drying on the enamel bond strengths and the surface free-energy of three single-step self-etch adhesives. Bovine mandibular incisors were mounted in self-curing resin and then wet ground with #600 silicon carbide (SiC) paper. The adhesives were applied according to the instructions of the respective manufacturers and then dried in a stream of normal (23°C) or warm (37°C) air for 5, 10, and 20 s. After visible-light irradiation of the adhesives, resin composites were condensed into a mold and polymerized. Ten samples per test group were stored in distilled water at 37°C for 24 h and then the bond strengths were measured. The surface free-energies were determined by measuring the contact angles of three test liquids placed on the cured adhesives. The enamel bond strengths varied according to the air-drying time and ranged from 15.8 to 19.1 MPa. The trends for the bond strengths were different among the materials. The value of the γS⁺ component increased slightly when drying was performed with a stream of warm air, whereas that of the γS⁻ component decreased significantly. These data suggest that warm air-drying is essential to obtain adequate enamel bond strengths, although increasing the drying time did not significantly influence the bond strength. © 2013 Eur J Oral Sci.

  18. Extracting dirt from water: a strengths-based approach to religion for African American same-gender-loving men.

    Science.gov (United States)

    Lassiter, Jonathan Mathias

    2014-02-01

    Religion is one of the most powerful and ubiquitous forces in African American same-gender-loving (SGL) men's lives. Research indicates that it has both positive and negative influences on the health behaviors and outcomes of this population. This paper presents a review of the literature that examines religion as a risk and protective factor for African American SGL men. A strengths-based approach to religion that aims to utilize its protective qualities and weaken its relation to risk is proposed. Finally, recommendations are presented for the use of a strengths-based approach to religion in clinical work and research.

  19. Percentage Level of Tannin fur Rabbit for Leather Concerning Stitch Tearing Strength, Tearing Strength and Flexibility

    Directory of Open Access Journals (Sweden)

    Mustakim Mustakim

    2012-02-01

    Full Text Available The purpose of this study was to find out the appropriate of tannin level for rabbit fur leather concerning stitch tearing strength, tearing strength, and flexibility. The result were expected to contribute good information for the society, leather craftsman, and further researchers about fur leather tanning especially rabbit fur leather with tannin concerning stitch tearing strength, tearing strength and flexibility. The material that used were 12 pieces of four months of rabbit skin. The research method was Completely Randomized Design, consist of three treatments of tannin, they were: M1 (mimosa 15%, M2 (mimosa 20%, and M3 (mimosa 25%. Each of treatment hold on four repetition, the variables which measured were stitch tearing strength, tearing strength, and flexibility of fur leather. Data were  analysed by analysis variance followed by Duncan’s Multiple Range Test. The result of this research indicate that the use level of tannin give significant influence (P<0.05 among stitch tearing strength, tearing strength. It gave a very significant influence (P<0.01 for flexibility of rabbit fur leather. Based on the result, can be concluded that 25 % of tannin (mimosa, produce the best  result on stitch tearing strength and tearing strength. The increase of tannin offer will decrease the flexibility of fur leather but the lowest tannin produced the best flexibility of fur leather (15 percent. The best quality of rabbit fur leather produced by 25 % of tannin.   Keywords : leather, tannin, quality

  20. Handgrip strength does not represent an appropriate measure to evaluate changes in muscle strength during an exercise intervention program in frail elderly people

    NARCIS (Netherlands)

    Tieland, C.A.B.; Verdijk, L.; Groot, de C.P.G.M.; Loon, van L.J.C.

    2015-01-01

    Although handgrip strength is considered a strong predictor of negative health outcomes, it is unclear whether handgrip strength represents a useful measure to evaluate changes in muscle strength following resistance-type exercise training in elderly people. We assessed whether measuring handgrip

  1. Influence of physical activity on vertebral strength during late adolescence.

    Science.gov (United States)

    Junno, Juho-Antti; Paananen, Markus; Karppinen, Jaro; Tammelin, Tuija; Niinimäki, Jaakko; Lammentausta, Eveliina; Niskanen, Markku; Nieminen, Miika T; Järvelin, Marjo-Riitta; Takatalo, Jani; Tervonen, Osmo; Tuukkanen, Juha

    2013-02-01

    Reduced vertebral strength is a clear risk factor for vertebral fractures. Men and women with vertebral fractures often have reduced vertebral size and bone mineral density (BMD). Vertebral strength is controlled by both genetic and developmental factors. Malnutrition and low levels of physical activity are commonly considered to result in reduced bone size during growth. Several studies have also demonstrated the general relationship between BMD and physical activity in the appendicular skeleton. In this study, we wanted to clarify the role of physical activity on vertebral bodies. Vertebral dimensions appear to generally be less pliant than long bones when lifetime changes occur. We wanted to explore the association between physical activity during late adolescence and vertebral strength parameters such as cross-sectional size and BMD. The association between physical activity and vertebral strength was explored by measuring vertebral strength parameters and defining the level of physical activity during adolescence. The study population consisted of 6,928 males and females who, at 15 to 16 and 19 years of age, responded to a mailed questionnaire inquiring about their physical activity. A total of 558 individuals at the mean age of 21 years underwent magnetic resonance imaging (MRI) scans. We measured the dimensions of the fourth lumbar vertebra from the MRI scans of the Northern Finland Birth Cohort 1986 and performed T2* relaxation time mapping, reflective of BMD. Vertebral strength was based on these two parameters. We analyzed the association of physical activity on vertebral strength using the analysis of variance. We observed no association between the level of physical activity during late adolescence and vertebral strength at 21 years. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Handgrip Strength as a Darwinian Fitness Indicator in Men

    Directory of Open Access Journals (Sweden)

    Andrew C. Gallup

    2018-04-01

    Full Text Available Handgrip strength (HGS is a robust measure of overall muscular strength and function, and has long been predictive of a multitude of health factors and physical outcomes for both men and women. The fact that HGS represents such a ubiquitous measure of health and vitality may reflect the significance of this trait during human evolution. This trait is also highly sexually dimorphic due to influences of androgenic hormones and fat-free body mass, suggesting that it has been further elaborated through sexual selection. Consistent with this view, research within evolutionary psychology and related fields has documented distinct relationships between HGS and measures of social and sexual behavior, especially in men. Here, we review studies across different societies and cultural contexts showing that male HGS predicts measures of aggression and social dominance, perceived formidability, male-typical body morphology and movement, courtship display, physical attractiveness, and sexual behavior and reproductive fitness. These findings underscore the value of including HGS as an independent measure within studies examining human sexual selection, and corroborate existing research suggesting that specific features of physical strength have and continue to be under positive directional selection in men.

  3. Handgrip Strength as a Darwinian Fitness Indicator in Men.

    Science.gov (United States)

    Gallup, Andrew C; Fink, Bernhard

    2018-01-01

    Handgrip strength (HGS) is a robust measure of overall muscular strength and function, and has long been predictive of a multitude of health factors and physical outcomes for both men and women. The fact that HGS represents such a ubiquitous measure of health and vitality may reflect the significance of this trait during human evolution. This trait is also highly sexually dimorphic due to influences of androgenic hormones and fat-free body mass, suggesting that it has been further elaborated through sexual selection. Consistent with this view, research within evolutionary psychology and related fields has documented distinct relationships between HGS and measures of social and sexual behavior, especially in men. Here, we review studies across different societies and cultural contexts showing that male HGS predicts measures of aggression and social dominance, perceived formidability, male-typical body morphology and movement, courtship display, physical attractiveness, and sexual behavior and reproductive fitness. These findings underscore the value of including HGS as an independent measure within studies examining human sexual selection, and corroborate existing research suggesting that specific features of physical strength have and continue to be under positive directional selection in men.

  4. Influence of different etching modes on bond strength and fatigue strength to dentin using universal adhesive systems.

    Science.gov (United States)

    Takamizawa, Toshiki; Barkmeier, Wayne W; Tsujimoto, Akimasa; Berry, Thomas P; Watanabe, Hedehiko; Erickson, Robert L; Latta, Mark A; Miyazaki, Masashi

    2016-02-01

    The purpose of this study was to determine the dentin bonding ability of three new universal adhesive systems under different etching modes using fatigue testing. Prime & Bond elect [PE] (DENTSPLY Caulk), Scotchbond Universal [SU] (3M ESPE), and All Bond Universal [AU] (Bisco) were used in this study. A conventional single-step self-etch adhesive, Clearfil Bond SE ONE [CS] (Kuraray Noritake Dental) was also included as a control. Shear bond strengths (SBS) and shear fatigue strength (SFS) to human dentin were obtained in the total-etch mode and self-etch modes. For each test condition, 15 specimens were prepared for the SBS and 30 specimens for SFS. SEM was used to examine representative de-bonded specimens, treated dentin surfaces and the resin/dentin interface for each test condition. Among the universal adhesives, PE in total-etch mode showed significantly higher SBS and SFS values than in self-etch mode. SU and AU did not show any significant difference in SBS and SFS between the total-etch mode and self-etch mode. However, the single-step self-etch adhesive CS showed significantly lower SBS and SFS values in the etch-and-rinse mode when compared to the self-etch mode. Examining the ratio of SFS/SBS, for PE and AU, the etch-and-rinse mode groups showed higher ratios than the self-etch mode groups. The influence of different etching modes on dentin bond quality of universal adhesives was dependent on the adhesive material. However, for the universal adhesives, using the total-etch mode did not have a negative impact on dentin bond quality. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  5. Influence of periodontal ligament simulation on bond strength and fracture resistance of roots restored with fiber posts

    Directory of Open Access Journals (Sweden)

    Ana Maria Estivalete MARCHIONATTI

    2014-10-01

    Full Text Available Objective: Considering that periodontal ligament simulation may influence the stress distribution over teeth restored with intraradicular retainers, this study aimed to assess the combined effect of mechanical cycling and periodontal ligament simulation on both the bond strength between fiber posts and root dentin and the fracture resistance of teeth restored using glass fiber posts. Material and Methods: Ninety roots were randomly distributed into 3 groups (n=10 (C-MC: control; P-MC: polyether; AS-MC: addition silicone to test bond strength and 6 groups (n=10 (C: control; P: polyether; AS: addition silicone, without mechanical cycling, and C-MC, P-MC and AS-MC with mechanical cycling to test fracture strength, according to the material used to simulate the periodontal ligament. For the bond strength test, fiber posts were cemented, cores were built, mechanical cycling was applied (2×106 cycles, 88 N, 2.2 Hz, and 45º incline, and the teeth cut into 3 slices (2 mm, which were then subjected to the push-out test at 1 mm/min. For the fracture strength test, fiber posts were cemented, cores were built, and half of the groups received mechanical cycling, followed by the compressive strength (45° to the long axis and 1 mm/min performed on all groups. Results: Periodontal ligament simulation did not affect the bond strength (p=0.244 between post and dentin. Simulation of periodontal ligament (p=0.153 and application of mechanical cycling (p=0.97 did not affect fracture resistance. Conclusions: The materials used to simulate the periodontal ligament did not affect fracture or bond strength, therefore periodontal ligament simulation using the tested materials could be considered optional in the conditions of the study.

  6. How the global layout of the mask influences masking strength.

    Science.gov (United States)

    Ghose, Tandra; Hermens, Frouke; Herzog, Michael H

    2012-12-10

    In visual backward masking, the perception of a target is influenced by a trailing mask. Masking is usually explained by local interactions between the target and the mask representations. However, recently it has been shown that the global spatial layout of the mask rather than its local structure determines masking strength (Hermens & Herzog, 2007). Here, we varied the mask layout by spatial, luminance, and temporal cues. We presented a vernier target followed by a mask with 25 elements. Performance deteriorated when the length of the two mask elements neighboring the target vernier was doubled. However, when the length of every second mask element was doubled, performance improved. When the luminance of the neighboring elements was doubled, performance also deteriorated but no improvement in performance was observed when every second element had a double luminance. For temporal manipulations, a complex nonmonotonic masking function was observed. Hence, changes in the mask layout by spatial, luminance, and temporal cues lead to highly different results.

  7. Influence of Race, Ethnicity and Social Determinants of Health on Diabetes Outcomes.

    Science.gov (United States)

    Walker, Rebekah J; Strom Williams, Joni; Egede, Leonard E

    2016-04-01

    There is strong evidence that race, ethnicity and social determinants of health significantly influence outcomes for patients with diabetes. A better understanding of the mechanisms of these relationships or associations would improve development of cost-effective, culturally tailored programs for patients with diabetes. This article reviews the current state of the literature on the influence of race and ethnicity and social determinants of health on process of care, quality of care and outcomes for diabetes, with particular emphasis on the rural South to give an overview of the state of the literature. The literature review shows that racial or ethnic differences in the clinical outcomes for diabetes, including glycemic, blood pressure (BP) and lipid control, continue to persist. In addition, the literature review shows that the role of social determinants of health on outcomes, and the possible role these determinants play in disparities have largely been ignored. Psychosocial factors, such as self-efficacy, depression, social support and perceived stress, show consistent associations with self-care, quality of life and glycemic control. Neighborhood factors, such as food insecurity, social cohesion and neighborhood esthetics have been associated with glycemic control. Perceived discrimination has also been associated with self-care and the psychological component of quality of life. Healthcare professionals need to be skilled in assessing social determinants of health and taking them into consideration in clinical care. In addition, more research is needed to identify the separate and combined influence of race and ethnicity and social determinants of health on process of care, quality of care and outcomes in diabetes, especially in the South, where the burden of disease is particularly high. Copyright © 2016 Southern Society for Clinical Investigation. All rights reserved.

  8. Genetic Variation in the Dopamine System Influences Intervention Outcome in Children with Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Rochellys Diaz Heijtz

    2018-02-01

    Interpretation: Naturally occurring genetic variation in the dopamine system can influence treatment outcomes in children with cerebral palsy. A polygenic dopamine score might be valid for treatment outcome prediction and for designing individually tailored interventions for children with cerebral palsy.

  9. Thermoelastic/plastic analysis of waste-container sleeve: III. Influence of salt strength on sleeve loading. Technical memorandum report (RSI-0018)

    International Nuclear Information System (INIS)

    Pariseau, W.G.

    1975-01-01

    Three combinations of salt tensile, compressive and shear strength in linear and nonlinear yield conditions used in the axially symmetric, large displacement thermoelastic/plastic waste-container/sleeve loading estimates show no influence on the analysis. The salt remains elastic throughout the excavation and subsequent 10 year heating period. Tensile stresses are not observed, tensile strength is thus not important to the analysis even at 10 percent of the compressive strength value. Although strictly applicable only to the conditions of the analyses reported here, the capability for incorporating arbitrary strength combinations in linear or non-linear yield conditions is demonstrated. Computer plots of principal stresses and displacement fields at various stages of the excavation and heating simulation aid in the visualization of repository concept mechanics and show the possible need for additional mesh refinement for more precise stress information

  10. Influence of the level of speed-strength preparedness on the agility of volleyball players 12–13 years old

    Directory of Open Access Journals (Sweden)

    Oleg Shevchenko

    2018-02-01

    Full Text Available Purpose: determine the impact level of indicators of speed-strength preparedness for the agility of young volleyball players 12–13 years. Material & Methods: analysis of scientific and methodological literature, pedagogical testing of speed-strength qualities and agility, pedagogical experiment, methods of mathematical statistics. The study involved 25 volleyball players aged 12–13 years, training in the basic training group of the second year of training of the sports club "Lokomotiv" in Kharkov. Young athletes were divided into an experimental – 13 people and a control –12 volleyball team. Results: after the introduction of the experimental methodology, a link was found between the level of speed-strength abilities and the agility of volleyball players. Conclusion: the positive influence of development of speed-strength qualities on indicators of agility of volleyball players that is necessary for selection of means and methods in training process of young athletes is proved.

  11. High risk pregnancy in the workplace. Influencing positive outcomes.

    Science.gov (United States)

    Cannon, R B; Schmidt, J V; Cambardella, B; Browne, S E

    2000-09-01

    Childbearing employees are well served by the occupational health nurse who promotes optimal preconceptual and pregnancy health practices, uses community resources, and maintains current knowledge about high risk pregnancy prevention and care. These broad goals of care can lead to decreased absenteeism, healthier and happier employees, and more positive outcomes of pregnancy. For employees with high risk pregnancies, the role of the occupational health nurse includes, but is not limited to, facilitating awareness with the employer, making suggestions for adjusting working conditions, making frequent assessments of the employee's needs, and communicating with prenatal health care providers. Occupational health nurses should never underestimate their role and potential influence on the mother, and on her significant other, for a positive outcome of her pregnancy.

  12. Comparison and Analysis of Steel Frame Based on High Strength Column and Normal Strength Column

    Science.gov (United States)

    Liu, Taiyu; An, Yuwei

    2018-01-01

    The anti-seismic performance of high strength steel has restricted its industrialization in civil buildings. In order to study the influence of high strength steel column on frame structure, three models are designed through MIDAS/GEN finite element software. By comparing the seismic performance and economic performance of the three models, the three different structures are comprehensively evaluated to provide some references for the development of high strength steel in steel structure.

  13. Factors influencing the tensile strength of repaired Achilles tendon: a biomechanical experiment study.

    Science.gov (United States)

    Jielile, Jiasharete; Bai, Jing Ping; Sabirhazi, Gulnur; Redat, Darebai; Yilihamu, Tuoheti; Xinlin, Baoltri; Hu, Geyang; Tang, Bin; Liang, Bing; Sun, Qi

    2010-10-01

    Operative treatment has been advocated as the method of choice to repair Achilles tendon rupture as surgery results in reduced re-rupture rate and faster rehabilitation. Many surgical techniques have been introduced allowing for postoperative early motion of the ankle joint. However, it is currently very difficult for surgeons to determine the optimal treatment conditions for ruptured Achilles tendon with an increasing number of end-to-end suture methods, suture materials, and epitenon suture techniques. In the present biomechanical experiment study based on an orthogonal design, thirty-two New Zealand white rabbits received Achilles tendon tenotomy and subsequent operative treatment to repair the tendon employing four end-to-end suture methods, four suture materials, and four epitenon suture techniques. The tensile strength of the repaired Achilles tendon was investigated at four rehabilitation periods, and in comparison with the results of another sixteen rabbits with normal Achilles tendons. The end-to-end suture method contributed most to the final Achilles tendon tensile strength in addition to rehabilitation period, with the highest values occurring with the use of the parachute-like ("Pa" bone) suture method. The other two factors, namely, suture material and epitenon suture technique, had relatively little influence on the results. The parachute-like ("Pa" bone) surgical technique is superior to the other three end-to-end suture methods, with enhanced tensile strength of the repaired tendon. This method allows for postoperative early kinesitherapy of the ankle and knee joints. Therefore, this technique is highly recommended in clinical situations for treatment of ruptured Achilles tendon. 2010 Elsevier Ltd. All rights reserved.

  14. Influence of gender on EVAR outcomes with new low-profile devices

    DEFF Research Database (Denmark)

    Bendermacher, B L W; Grootenboer, Nathalie; Cuypers, Ph W

    2013-01-01

    Women have not benefitted to the same extent as men of endovascular abdominal aortic repair (EVAR). Besides differences in hormones and the higher rate of undiagnosed cardiovascular disease, there are anatomical differences between men and women influencing the outcome of endovascular treatment o...

  15. Influence of surface treatment of yttria-stabilized tetragonal zirconia polycrystal with hot isostatic pressing on cyclic fatigue strength.

    Science.gov (United States)

    Iijima, Toshihiko; Homma, Shinya; Sekine, Hideshi; Sasaki, Hodaka; Yajima, Yasutomo; Yoshinari, Masao

    2013-01-01

    Hot isostatic pressing processed yttria-stabilized tetragonal zirconia polycrystal (HIP Y-TZP) has the potential for application to implants due to its high mechanical performance. The aim of this study was to investigate the influence of surface treatment of HIP Y-TZP on cyclic fatigue strength. HIP Y-TZP specimens were subjected to different surface treatments. Biaxial flexural strength was determined by both static and cyclic fatigue testing. In the cyclic fatigue test, the load was applied at a frequency of 10 Hz for 10(6) cycles in distilled water at 37°C. The surface morphology, roughness, and crystal phase of the surfaces were also evaluated. The cyclic fatigue strength (888 MPa) of HIP Y-TZP with sandblasting and acid-etching was more than twice that of Y-TZP as specified in ISO 13356 for surgical implants (320 MPa), indicating the clinical potential of this material.

  16. Influence of Temporary Cements on the Bond Strength of Self-Adhesive Cement to the Metal Coronal Substrate.

    Science.gov (United States)

    Peixoto, Raniel Fernandes; De Aguiar, Caio Rocha; Jacob, Eduardo Santana; Macedo, Ana Paula; De Mattos, Maria da Gloria Chiarello; Antunes, Rossana Pereira de Almeida

    2015-01-01

    This research evaluated the influence of temporary cements (eugenol-containing [EC] or eugenol-free [EF]) on the tensile strength of Ni-Cr copings fixed with self-adhesive resin cement to the metal coronal substrate. Thirty-six temporary crowns were divided into 4 groups (n=9) according to the temporary cements: Provy, Dentsply (eugenol-containing), Temp Cem, Vigodent (eugenol-containing), RelyX Temp NE, 3M ESPE (eugenol-free) and Temp Bond NE, Kerr Corp (eugenol-free). After 24 h of temporary cementation, tensile strength tests were performed in a universal testing machine at a crosshead speed of 0.5 mm/min and 1 kN (100 kgf) load cell. Afterwards, the cast metal cores were cleaned by scraping with curettes and air jet. Thirty-six Ni-Cr copings were cemented to the cast metal cores with self-adhesive resin cement (RelyX U200, 3M ESPE). Tensile strength tests were performed again. In the temporary cementation, Temp Bond NE (12.91 ± 2.54) and Temp Cem (12.22 ± 2.96) presented the highest values of tensile strength and were statistically similar to each other (p>0.05). Statistically significant difference (pcementation of Ni-Cr copings with self-adhesive resin cement. In addition, Temp Cem (120.68 ± 48.27) and RelyX Temp NE (103.04 ± 26.09) showed intermediate tensile strength values. In conclusion, the Provy eugenol-containing temporary cement was associated with the highest bond strength among the resin cements when Ni-Cr copings were cemented to cast metal cores. However, the eugenol cannot be considered a determining factor in increased bond strength, since the other tested cements (1 eugenol-containing and 2 eugenol-free) were similar.

  17. Influence of brazing conditions on the strength of brazed joints of alumina dispersion-strengthened copper to 316 stainless steel

    International Nuclear Information System (INIS)

    Nishi, H.; Kikuchi, K.

    1998-01-01

    Brazing of alumina dispersion-strengthened copper (DS Cu) to 316 stainless steel were conducted in order to investigate the influence of filler metals and brazing conditions on the joint strength. The brazing were performed with a silver-base (BAg-8) and three kinds of gold-base (BAu-2.4.11) filler metals with varying brazing joint clearance and brazing time. The filler metal had a greater effect on the joint strength than the brazing joint clearance and brazing time. The joint with BAu-2 was superior to the joint with other filler metals. The tensile strength of the joint with BAu-2 was as large as that of DS Cu, however, the Charpy and low cycle fatigue strength were lower than those of DS Cu. The DS Cu melted near the brazed zone, consequently recrystallization and agglomeration of alumina occurred in the diffusion layer for all filler metals. The grain size after the recrystallization was small in order of BAu-2. BAu-4 and BAu-11, that was in accordance with the order of the brazing temperature. The excellent fracture strength for the joint with BAu-2 was attributed to the smallest grain size. (orig.)

  18. Influence of tool geometry and process parameters on macrostructure and static strength in friction stir spot welded polyethylene sheets

    International Nuclear Information System (INIS)

    Bilici, Mustafa Kemal; Yuekler, Ahmet Irfan

    2012-01-01

    Highlights: → All velding parameters and different tool geometries have demonstrated a different effects on weld strength. → Friction stir spot welding of polyethylene mechanical scission is very important. → Metric screw the tool has a great influence on the weld strength of FSSW. -- Abstract: The effect of important welding parameters and tool properties that are effective on static strength in friction stir spot welds of polyethylene sheets were studied. Six different tool pin profiles (straight cylindrical, tapered cylindrical, threaded cylindrical, triangular, square and hexagonal) with different shoulder geometries, different pin length, pin angle and concavity angle were used to fabricate the joints. The tool rotational speed, tool plunge depth and dwell time were determined welding parameters. All the welding operations were done at the room temperature. Welding force and welding zone material temperature measurements were also done. Lap-shear tests were carried out to find the weld static strength. Weld cross section appearance observations were also done. From the experiments, the effect of pin profile, pin length, pin angle, dwell time and tool rotational speed on friction stir spot welding formation and weld strength was determined.

  19. Influence of the waste glass in the axial compressive strength of Portland cement concrete

    International Nuclear Information System (INIS)

    Miranda Junior, E.J.P.; Paiva, A.E.M.

    2012-01-01

    In this work, was studied the influence of the incorporation of waste glass, coming from the stage of thinning and polishing of a company of thermal glass treatments, in the axial compressive strength of Portland cement concrete. The coarse and ground aggregates used was crushed stone and sand, respectively. For production of the concrete, percentages of glass residues of 5%, 10% and 20% had been used in substitution to the sand, and relations water/cement (a/c) 0,50, 0,55 and 0,58. The cure of the test bodies was carried through in 7, 14 and 28 days. The statistics analysis of the results was carried out through of the analysis of variance for each one of the cure times. From the results of the compressive strength of the concrete, it could be observed that the concrete has structural application for the relation a/c 0,5, independently of waste glass percentage used, and for the relation a/c 0,55 with 20% of waste glass. (author)

  20. Factors that influence the outcome of information technology projects in South Africa: An empirical investigation

    Directory of Open Access Journals (Sweden)

    Carl Marnewick

    2009-12-01

    Full Text Available Purpose: In developing countries such as South Africa, many organisations are reliant on information and communication technology (ICT to provide accurate, relevant and timely information. For organisations to obtain and sustain a competitive advantage, ICT systems are constantly implemented, upgraded, modified or replaced. These initiatives are often managed as projects. While there is an increasing amount of both financial resources and effort being spent on ICT, these projects are not always delivered within the predetermined project constraints. This implies additional time to complete, as well as additional costs, as resources are not released in time to participate in other projects. It is therefore important to understand the factors that influence the outcome of South African ICT projects relative to their original constraints. Problem Investigated: The goal of this article is to determine the factors that influence South African ICT projects, taking into consideration the fact that most current published research on this topic was done within the context of a developed country such as the USA and Europe. Design and/or methodology: The outcomes of ICT projects in South Africa as well as the factors that influence them were determined through an extensive survey. An analysis was done on the factors together with a correlation between the main factors contributing to project outcomes. The purpose of this was to establish if a factor's presence or absence influenced the eventual outcome. Findings: The factors that contribute to a successful outcome are often outside the direct control of the project manager and tend to be complex in nature. One factor that does stand out is that the alignment of projects with business objectives influences their perceived success. Originality/Value: The benefits of this article are that it firstly provides a South African perspective of current ICT project management practices, and secondly, it highlights

  1. The Influence of GI and GII on the Compression After Impact Strength of Carbon Fiber/Epoxy Laminates and Sandwich Structure

    Science.gov (United States)

    Nettles, A. T.; Scharber, L. L.

    2017-01-01

    This study measured the compression after impact strength of IM7 carbon fiber laminates made from epoxy resins with various mode I and mode II toughness values to observe the effects of these toughness values on the resistance to damage formation and subsequent residual compression strength-carrying capabilities. Both monolithic laminates and sandwich structure were evaluated. A total of seven different epoxy resin systems were used ranging in approximate GI values of 245-665 J/sq m and approximate GII values of 840-2275 J/sq m. The results for resistance to impact damage formation showed that there was a direct correlation between GII and the planar size of damage, as measured by thermography. Subsequent residual compression strength testing suggested that GI had no influence on the measured values and most of the difference in compression strength was directly related to the size of damage. Thus, delamination growth assumed as an opening type of failure mechanism does not appear to be responsible for loss of compression strength in the specimens examined in this study.

  2. Predicting the drying shrinkage behavior of high strength portland cement mortar under the combined influence of fine aggregate and steel micro fiber

    International Nuclear Information System (INIS)

    Li, Zhengqi

    2017-01-01

    The workability, 28-day compressive strength and free drying shrinkage of a very high strength (121-142 MPa) steel micro fiber reinforced portland cement mortar were studied under a combined influence of fine aggregate content and fiber content. The test results showed that an increase in the fine aggregate content resulted in decreases in the workability, 28-day compressive strength and drying shrinkage of mortar at a fixed fiber content. An increase in the fiber content resulted in decreases in the workability and drying shrinkage of mortar, but an increase in the 28-day compressive strength of mortar at a fixed fine aggregate content. The modified Gardner model most accurately predicted the drying shrinkage development of the high strength mortars, followed by the Ross model and the ACI 209R-92 model. The Gardner model gave the least accurate prediction for it was developed based on a database of normal strength concrete. [es

  3. Predicting the drying shrinkage behavior of high strength portland cement mortar under the combined influence of fine aggregate and steel micro fiber

    Directory of Open Access Journals (Sweden)

    Zhengqi Li

    2017-03-01

    Full Text Available The workability, 28-day compressive strength and free drying shrinkage of a very high strength (121-142 MPa steel micro fiber reinforced portland cement mortar were studied under a combined influence of fine aggregate content and fiber content. The test results showed that an increase in the fine aggregate content resulted in decreases in the workability, 28-day compressive strength and drying shrinkage of mortar at a fixed fiber content. An increase in the fiber content resulted in decreases in the workability and drying shrinkage of mortar, but an increase in the 28-day compressive strength of mortar at a fixed fine aggregate content. The modified Gardner model most accurately predicted the drying shrinkage development of the high strength mortars, followed by the Ross model and the ACI 209R-92 model. The Gardner model gave the least accurate prediction for it was developed based on a database of normal strength concrete.

  4. Influence of Temperature on Workability and Compressive Strength of Ordinary Concrete with High Calcium Fly Ash

    Directory of Open Access Journals (Sweden)

    Gołaszewski Jacek

    2017-06-01

    Full Text Available The rheological properties of fresh ordinary concrete are closely affected by temperature and time. The paper presents the study of consistency of fresh concrete mixtures made with Portland cement and cement with calcareous fly ash. Two types of admixtures were used. It was proven that the temperature has a clear effect on workability and compressive strength concrete. Influence on workability can be reduced by selecting the appropriate superplasticizer and cement.

  5. Effectiveness of acute in-hospital physiotherapy with knee-extension strength training in reducing strength deficits in patients with a hip fracture: A randomised controlled trial.

    Directory of Open Access Journals (Sweden)

    Lise Kronborg

    Full Text Available Is acute in-hospital physiotherapy with additional progressive knee-extension strength training (ST of the fractured limb more effective in reducing knee-extension strength deficit at follow-up compared to physiotherapy without strength training in patients with a hip fracture?Assessor blinded, randomised controlled trial with intention-to-treat analysis.90 patients with a hip fracture admitted to an acute orthopaedic Hip Fracture Unit at a university hospital between October 2013 and May 2015.Daily physiotherapy with or without progressive knee-extension strength training (10RM, 3 x 10 repetitions, of the fractured limb using ankle weight cuffs conducted by ward physical therapists during hospital stay.Primary outcome was the change in maximal isometric knee-extension strength in the fractured limb in percentage of the non-fractured limb from inclusion to postoperative day 10 or discharge (follow-up. Secondary outcome was Timed Up and Go test measured early after surgery and at follow-up.In the intention-to-treat analysis of between-group differences, the primary outcome improved 8.1% (95% CI -2.3; 18.4 by additional strength training from baseline to follow-up. In the per-protocol analysis of non-missing data, significant between-group improvements by 10.5% (95% CI 0.3; 20.7 were found in favour of additional ST. No significant between-group differences were found in any secondary outcome.Physiotherapy with addition of 5 sessions of ST yielded no additional improvements compared to physiotherapy without strength training in reducing the knee-extension strength deficit at follow-up in patients with a hip fracture. It is debatable whether larger improvements than the observed 8-10% can be expected given that only five exercise sessions, on average, were completed. In fragile patients with a hip fracture in the acute phase, where the ability to participate in functional exercise is compromised, we still consider early strength training a

  6. Association between MRI-defined osteoarthritis, pain, function and strength 3-10 years following knee joint injury in youth sport.

    Science.gov (United States)

    Whittaker, Jackie L; Toomey, Clodagh M; Woodhouse, Linda J; Jaremko, Jacob L; Nettel-Aguirre, Alberto; Emery, Carolyn A

    2017-10-10

    Youth and young adults who participate in sport have an increased risk of knee injury and subsequent osteoarthritis. Improved understanding of the relationship between structural and clinical outcomes postinjury could inform targeted osteoarthritis prevention interventions. This secondary analysis examines the association between MRI-defined osteoarthritis and self-reported and functional outcomes, 3-10 years following youth sport-related knee injury in comparison to healthy controls. Participants included a subsample (n=146) of the Alberta Youth Prevention of Early Osteoarthritis cohort: specifically, 73 individuals with 3-10 years history of sport-related intra-articular knee injury and 73 age-matched, sex-matched and sport-matched controls with completed MRI studies. Outcomes included: MRI-defined osteoarthritis, radiographic osteoarthritis, Knee Injury and Osteoarthritis Outcome Score, Intermittent and Constant Osteoarthritis Pain, knee extensor/flexor strength, triple-hop and Y-balance test. Descriptive statistics and univariate logistic regression were used to compare those with and without MRI-defined osteoarthritis. Associations between MRI-defined osteoarthritis and each outcome were assessed using multivariable linear regression considering the influence of injury history, sex, body mass index and time since injury. Participant median age was 23 years (range 15-27), and 63% were female. MRI-defined osteoarthritis varied by injury history, injury type and surgical history and was not isolated to participants with ACL and/or meniscal injuries. Those with a previous knee injury had 10-fold (95% CI 2.3 to 42.8) greater odds of MRI-defined osteoarthritis than uninjured participants. MRI-defined osteoarthritis was independently significantly associated with quality of life, but not symptoms, strength or function. MRI-detected structural changes 3-10 years following youth sport-related knee injury may not dictate clinical symptomatology, strength or function

  7. Influence of aluminium sheet surface modification on the self-piercing riveting process and the joint static lap shear strength

    OpenAIRE

    Li, Dezhi

    2017-01-01

    Self-piercing riveting (SPR) has been widely used in automotive as one of the major joining technologies for aluminium structures due to its advantages over some of the more traditional joining technologies. Research has shown that friction is a very important factor that influences both the riveting process and the joint strength for SPR, but these influences have not been fully understood. In this paper, AA5754 sheets with different surface textures, such as original with solid wax, hot wat...

  8. The Influence of Consumers€™ Tie Strength, Homophily and Source Credibility Toward Electronic Word-of-mouth (Ewom) Behavior

    OpenAIRE

    Oroh, Winda Lely

    2014-01-01

    Electronic word-of-mouth (eWOM) in the form of online product reviews can influence the sales of a product and/or service, and that informational€based determinants are very important to consumers when evaluating reviews. The purpose of this research is to analyze the influence of consumers€™ tie strength, homophily, and source credibility toward electronic word-of-mouth behavior (eWOM). This research used quantitative analyze. The method used to analyze the data is the Multiple Regression A...

  9. Influence of Graphene Nanosheets on Rheology, Microstructure, Strength Development and Self-Sensing Properties of Cement Based Composites

    Directory of Open Access Journals (Sweden)

    Sardar Kashif Ur Rehman

    2018-03-01

    Full Text Available In this research, Graphene oxide (GO, prepared by modified hammer method, is characterized using X-ray Diffraction (XRD, Fourier Transform Infrared (FT-IR Spectrometry and Raman spectra. The dispersion efficiency of GO in aqueous solution is examined by Ultraviolet–visible spectroscopy and it is found that GO sheets are well dispersed. Thereafter, rheological properties, flow diameter, hardened density, compressive strength and electrical properties of GO based cement composite are investigated by incorporating 0.03% GO in cement matrix. The reasons for improvement in strength are also discussed. Rheological results confirm that GO influenced the flow behavior and enhanced the viscosity of the cement based system. From XRD and Thermogravimetric Analysis (TGA results, it is found that more hydration occurred when GO was incorporated in cement based composite. The GO based cement composite improves the compressive strength and density of mortar by 27% and 1.43%, respectively. Electrical properties results showed that GO–cement based composite possesses self-sensing characteristics. Hence, GO is a potential nano-reinforcement candidate and can be used as self-sensing sustainable construction material.

  10. The Association between Maximal Bench Press Strength and Isometric Handgrip Strength among Breast Cancer Survivors

    Science.gov (United States)

    Rogers, Benjamin H.; Brown, Justin C.; Gater, David R.; Schmitz, Kathryn H.

    2016-01-01

    Objective One-repetition maximum (1-RM) bench press strength is considered the gold standard to quantify upper-body muscular strength. Isometric handgrip strength is frequently used as a surrogate for 1-RM bench press strength among breast cancer (BrCa) survivors. The relationship between 1-RM bench press strength and isometric handgrip strength, however, has not been characterized among BrCa survivors. Design Cross-sectional study. Setting Laboratory. Participants Community-dwelling BrCa survivors. Interventions Not applicable. Main Outcome Measure 1-RM bench press strength was measured with a barbell and exercise bench. Isometric handgrip strength was measured using an isometric dynamometer with three maximal contractions of left and right hands. All measures were conducted by staff with training in clinical exercise testing. Results Among 295 BrCa survivors, 1-RM bench press strength was 18.2±6.1 kg (range: 2.2-43.0) and isometric handgrip strength was 23.5±5.8 kg (range: 9.0-43.0). The strongest correlate of 1-RM bench press strength was the average isometric handgrip strength of both hands (r=0.399; Pisometric handgrip strength of both hands overestimated 1-RM bench press strength by 4.7 kg (95% limits of agreement: −8.2 to 17.6). In a multivariable linear regression model, the average isometric handgrip strength of both hands (β=0.31; Pstrength (R2=0.23). Conclusions Isometric handgrip strength is a poor surrogate for 1-RM bench press strength among BrCa survivors. 1-RM bench press and isometric handgrip strength quantify distinct components of muscular strength. PMID:27543047

  11. Influence of Fracture Width on Sealability in High-Strength and Ultra-Low-Permeability Concrete in Seawater

    OpenAIRE

    Fukuda, Daisuke; Nara, Yoshitaka; Hayashi, Daisuke; Ogawa, Hideo; Kaneko, Katsuhiko

    2013-01-01

    For cementitious composites and materials, the sealing of fractures can occur in water by the precipitation of calcium compounds. In this study, the sealing behavior in a macro-fractured high-strength and ultra-low-permeability concrete (HSULPC) specimen was investigated in simulated seawater using micro-focus X-ray computed tomography (CT). In particular, the influence of fracture width (0.10 and 0.25 mm) on fracture sealing was investigated. Precipitation occurred mainly at the outermost pa...

  12. Strength of wood versus rate of testing - A theoretical approach

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    2007-01-01

    Strength of wood is normally measured in ramp load experiments. Experience shows that strength increases with increasing rate of testing. This feature is considered theoretically in this paper. It is shown that the influence of testing rate is a phenomenon, which depends on the quality...... of the considered wood. Low quality wood shows lesser influence of testing rate. This observation agrees with the well-known statement made by Borg Madsen that weak wood subjected to a constant load, has a longer lifetime than strong wood. In general, the influence of testing rate on strength increases...

  13. Influence of Immersion Conditions on The Tensile Strength of Recycled Kevlar®/Polyester/Low-Melting-Point Polyester Nonwoven Geotextiles through Applying Statistical Analyses

    Directory of Open Access Journals (Sweden)

    Jing-Chzi Hsieh

    2016-05-01

    Full Text Available The recycled Kevlar®/polyester/low-melting-point polyester (recycled Kevlar®/PET/LPET nonwoven geotextiles are immersed in neutral, strong acid, and strong alkali solutions, respectively, at different temperatures for four months. Their tensile strength is then tested according to various immersion periods at various temperatures, in order to determine their durability to chemicals. For the purpose of analyzing the possible factors that influence mechanical properties of geotextiles under diverse environmental conditions, the experimental results and statistical analyses are incorporated in this study. Therefore, influences of the content of recycled Kevlar® fibers, implementation of thermal treatment, and immersion periods on the tensile strength of recycled Kevlar®/PET/LPET nonwoven geotextiles are examined, after which their influential levels are statistically determined by performing multiple regression analyses. According to the results, the tensile strength of nonwoven geotextiles can be enhanced by adding recycled Kevlar® fibers and thermal treatment.

  14. Applying Strengths Model principles to build a rural community-based mental health support service and achieve recovery outcomes.

    Science.gov (United States)

    Dunstan, Debra; Anderson, Donnah

    2018-02-01

    The Personal Helpers and Mentors (PHaMs) service is a non-clinical, community-based Australian Government initiative aimed at increasing opportunities for recovery for people whose lives are severely affected by mental illness. Using a strengths-based recovery model, PHaMs caseworkers support and mentor people 'at risk of falling through the gaps' between state funded clinical treatment services and federally funded social services (such as supported housing, education and employment). While there is evidence that PHaMs realises its aim in metropolitan areas, little is known about how services are developed and function in low resource rural settings and what outcomes are achieved. These questions were addressed in a case study of a PHaMs service in a rural town in the state of New South Wales, Australia. Data were collected from two sources: local service documents prepared for staff orientation and operational purposes, and records and reports of service participants\\' performance and achievements. Participants\\' gains in wellbeing, recovery goals, and the target outcome areas of increased access to services, increased personal capacity and self-reliance, and increased community participation, were gathered from self-reports. The Role Functioning Scale was used as a measure of caseworker ratings of participants\\' adaptive functioning. The qualitative data were examined for semantic content and underlying themes. The quantitative analyses involved repeated measures and between-groups comparisons of uncontrolled pre-test–post-test and retrospective pre-test data. From commencement of the service in October 2009 to June 2014, an estimated 31% of the people living with severe mental illness in the local government area had accessed the PHaMs service (N=126; mean age 31.9 years; 42% male, 27% Aboriginal). The document analysis revealed that despite a lack of detail on how a PHaMs service should be developed or delivered, by focusing on the goal of client recovery

  15. Leader Affect and Leadership Effectiveness: How leader affective displays influence follower outcomes

    NARCIS (Netherlands)

    V.A. Visser (Victoria)

    2013-01-01

    textabstractThe aim of this dissertation is to uncover the relationship between leader affective displays and leadership effectiveness. Five empirical studies were conducted to test the influence of several leader affective displays on different follower outcomes that indicate leadership

  16. Influence of irradiation on high-strength graphites

    International Nuclear Information System (INIS)

    Virgil'ev, Yu.S.; Grebennik, V.N.; Kalyagina, I.P.

    1989-01-01

    To ensure efficiency of the graphite elements of the construction of the masonry of reactors, the graphite must possess high radiation stability, strength, and heat resistance. In this connection, the physical properties of graphites based on uncalcined petroleum coke with a binder - high-temperature hard coal pitch - the amount of which reaches 40% are considered in this paper

  17. Test-Retest Reliability of Handgrip Strength as an Outcome Measure in Patients With Symptoms of Shoulder Impingement Syndrome.

    Science.gov (United States)

    Savva, Christos; Mougiaris, Paraskevas; Xadjimichael, Christoforos; Karagiannis, Christos; Efstathiou, Michalis

    The purpose of this study was to investigate the degree of test-retest reliability of grip strength measurement using a hand dynamometer in patients with shoulder impingement syndrome. A total of 19 patients (10 women and 9 men; mean ± standard deviation age, 33.2 ± 12.9 years; range 18-59 years) with shoulder impingement syndrome were measured using a hand dynamometer by the same data collector in 2 different testing sessions with a 7-day interval. During each session, patients were encouraged to exert 3 maximal isometric contractions on the affected hand and the mean value of the 3 efforts (measured in kilogram-force [Kgf]) was used for data analysis. The intraclass correlation coefficient (ICC 2,1 ) as well as the standard error of measurement (SEM) and Bland-Altman plot were used to estimate the degree of test-retest reliability and the measurement error, respectively. Grip strength data analysis revealed an ICC 2,1 score of 0.94, which, based on the Shrout classification, is considered as excellent test-retest reliability of grip strength measurement. The small values of SEMs reported in both sessions (SEM 1 , 2.55 Kgf; SEM 2 , 2.39 Kgf) and the small width of the 95% limits of agreement in the Bland-Altman plot (ranging from -7.39 Kgf to 7.03 Kgf) reflected the measurement precision and the narrow variation of the differences during the 2 testing sessions. Results from this study identified excellent test-retest reliability of grip strength measurement in shoulder impingement syndrome, indicating its potential use as an outcome measure in clinical practice. Copyright © 2018. Published by Elsevier Inc.

  18. Feasibility and outcomes of a classical Pilates program on lower extremity strength, posture, balance, gait, and quality of life in someone with impairments due to a stroke.

    Science.gov (United States)

    Shea, Sarah; Moriello, Gabriele

    2014-07-01

    Pilates is a method that can potentially be used for stroke rehabilitation to address impairments in gait, balance, strength, and posture. The purpose of this case report was to document the feasibility of using Pilates and to describe outcomes of a 9-month program on lower extremity strength, balance, posture, gait, and quality of life in an individual with stroke. The participant was taught Pilates exercises up to two times per week for nine months in addition to traditional rehabilitation in the United States. Outcomes were assessed using the Berg Balance Scale (BBS), Stroke Impact Scale (SIS), GAITRite System(®), 5 repetition sit-to-stand test (STST), and flexicurve. Improvements were found in balance, lower extremity strength, and quality of life. Posture and gait speed remained the same. While these changes cannot be specifically attributed to the intervention, Pilates may have added to his overall rehabilitation program and with some modifications was feasible to use in someone with a stroke. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Influence of Welding Time on Tensile-Shear Strength of Linear Friction Welded Birch (Betula pendula L. Wood

    Directory of Open Access Journals (Sweden)

    Jussi Ruponen

    2015-04-01

    Full Text Available The purpose of this work was to determine the optimal welding time for linear friction welding of birch (Betula pendula L. wood while keeping the other parameters constant and at similar levels compared to other species in a similar density range. Specimens with dimensions of 20 × 5 × 150 mm3 were welded together, and the influence of welding time (2.5, 3.0, 3.5, and 4.0 s on the mechanical properties of the specimens was determined. The studies included a tensile-shear strength test as well as visual estimation of wood failure percentage (WFP. Additionally, X-ray microtomographic imaging was used to investigate and characterise the bond line properties as a non-destructive testing method. The highest mean tensile-shear strength, 7.9 MPa, was reached with a welding time of 3.5 s. Generally, all four result groups showed high, yet decreasing proportional standard deviations as the welding time increased. X-ray microtomographic images and analysis express the heterogeneity of the weld line clearly as well. According to the averaged group-wise results, WFP and tensile-shear strength correlated positively with an R2 of 0.93. An extrapolation of WFP to 65% totals a tensile-shear strength of 10.6 MPa, corresponding to four common adhesive bonds determined for beech.

  20. Influence of frequency on shear fatigue strength of resin composite to enamel bonds using self-etch adhesives.

    Science.gov (United States)

    Takamizawa, Toshiki; Scheidel, Donal D; Barkmeier, Wayne W; Erickson, Robert L; Tsujimoto, Akimasa; Latta, Mark A; Miyazaki, Masashi

    2016-09-01

    The purpose of this study was to determine the influence of different frequency rates on of bond durability of self-etch adhesives to enamel using shear fatigue strength (SFS) testing. A two-step self-etch adhesive (OX, OptiBond XTR), and two single step self-etch adhesives (GB, G-ӕnial Bond and SU, Scotchbond Universal) were used in this study. The shear fatigue strength (SFS) to enamel was obtained. A staircase method was used to determine the SFS values with 50,000 cycles or until failure occurred. Fatigue testing was performed at frequencies of 5Hz, 10Hz, and 20Hz. For each test condition, 30 specimens were prepared for the SFS testing. Regardless of the bond strength test method, OX showed significantly higher SFS values than the two single-step self-etch adhesives. For each of the three individual self-etch adhesives, there was no significant difference in SFS depending on the frequency rate, although 20Hz results tended to be higher. Regardless of the self-etch adhesive system, frequencies of 5Hz, 10Hz, and 20Hz produced similar results in fatigue strength of resin composite bonded to enamel using 50,000 cycles or until bond failure. Accelerated fatigue testing provides valuable information regarding the long term durability of resin composite to enamel bonding using self-etch adhesive system. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. INFLUENCE OF PERSONALITY ON THE OUTCOME OF TREATMENT IN DEPRESSION : SYSTEMATIC REVIEW AND META-ANALYSIS

    NARCIS (Netherlands)

    Newton-Howes, Giles; Tyrer, Peter; Johnson, Tony; Mulder, Roger; Kool, Simone; Dekker, Jack; Schoevers, Robert

    There continues to be debate about the influence of personality disorder on the outcome of depressive disorders and is relative interactions with treatment. To determine whether personality disorder, both generically and in terms of individual clusters, leads to a worse outcome in patients with

  2. Strength properties of sandy soil-cement admixtures

    OpenAIRE

    Sara Rios; António Joaquim Pereira Viana Da Fonseca

    2009-01-01

    This paper will focus on the sensitivity of strength and stiffness properties of silty-sands, from granitic residual soil, which can be converted to a highly improved material if stabilized with cement. The study of soil stabilization with cement demands to quantify the influence of the cement percentage, porosity and water content adopted in the admixing process for different stresses and physical states. Firstly, this influence was quantified in terms of the unconfined strength and maximum ...

  3. Evaluation of in-place concrete strength by core testing.

    Science.gov (United States)

    2016-11-01

    The overall objective of the work contained in this report is to develop an ALDOT procedure to evaluate core strength results obtained under various conditions. Since there are many factors that influence the apparent strength of cores, strength corr...

  4. Influence of the welding process on martensitic high strength steel

    Directory of Open Access Journals (Sweden)

    Petr Hanus

    2014-07-01

    Full Text Available The subject of the study is martensitic 22MnB5 steels, which are used in the automotive industry. The main purpose of the performed analyses is a study of strength differences in heat affected zones of the spot welding. For the needs of the strength decrease assessment, the critical layer of the heat affected area was experimentally simulated. The aim of the work is to determine the most suitable methodology for evaluating the local changes of the elastic-plastic material response. The aim of this work is to determine the optimal methods for the determination of the yield strength and to find a firming trend in these zones.

  5. Influence of Er,Cr: YSGG laser on bond strength of self-adhesive resin cement

    Directory of Open Access Journals (Sweden)

    Matheus Coelho Bandéca

    2012-08-01

    Full Text Available The purpose of this study was to investigate the bond strength of fiber post previously laser treated root canals. Forty single-rooted bovine teeth were endodontically treated, randomly and equally divided into two main groups according to the type of pretreatment: G1: 2.5% NaOCl (control group; and G2: Er,Cr:YSGG laser. Each group was further subdivided into 2 groups based on the category of adhesive systems/ luting materials used: a: an etch-and-rinse resin cement (Single Bond/RelyX ARC; 3M ESPE, and b: a self-adhesive resin cement (Rely X Unicem; 3M ESPE. Three 1.5 mm thick slabs were obtained per root and the push-out test was performed at a crosshead speed of 0.5 mm/min until post dislodgement occurred. Data were analyzed by ANOVA and post-hoc Tukey's test at a pre-set alpha of 0.05. Analysis of variance showed no statistically significant difference (p > 0.05 among the groups G1a (25.44 ± 2.35 and G1b (23.62 ± 3.48, G2a (11.77 ± 2.67 and G2b (9.93 ± 3.37. Fractures were observed at the interface between the dentin and the resin in all groups. The Er,Cr:YSGG laser irradiation did not influence on the bond strength of the resin cements and the etch-and-rinse resin cement had better results on bond strength than self-adhesive resin cement.

  6. Influence of Random Inclusion of Coconut Fibres on the Short term Strength of Highly Compressible Clay

    Science.gov (United States)

    Ramani Sujatha, Evangelin; SaiSree, S.; Prabalini, C.; Aysha Farsana, Z.

    2017-07-01

    The choice of natural fibres for soil stabilization provides an economic, safe and eco-friendly alternative to improve the properties of soil. They are an important step forward toward sustainable development. An attempt was made to study the influence of the random addition of untreated coconut fibres on the short term strength of soil, its stress-strain behavior, compaction characteristics and index properties. The soil selected for the study is a highly compressible clay sample with a liquid limit of 52.5 % and plasticity index of 38 %. The soil has no organic content. The study reveals that the compaction curves tend to shift to the right side, indicating more plastic behavior with the addition of fibres. The addition of fibres also reorient the soil structure to a more dispersed fashion. A significant increase in the unconfined compressive strength is also observed. An increase of nearly 51 % in the unconfined compressive strength is observed at 0.75 % coir inclusion. The stress-strain behavior of the soil shows a shift toward more plastic behavior. The mode of failure of the soil specimen is by cracking and with fibre inclusion, length of the failure cracks is restrained as the fibre tends to hold the cracks together, resulting in shorter cracks, with significant bulging of the specimen at failure.

  7. Influence of water storage on fatigue strength of self-etch adhesives.

    Science.gov (United States)

    Takamizawa, Toshiki; Barkmeier, Wayne W; Tsujimoto, Akimasa; Scheidel, Donal D; Watanabe, Hidehiko; Erickson, Robert L; Latta, Mark A; Miyazaki, Masashi

    2015-12-01

    The purpose of this study was to determine enamel and dentin bond durability after long-term water storage using self-etch adhesives. Two single step self-etch adhesives (SU, Scotchbond Universal and GB, G-ӕnial Bond) and a two-step self-etch adhesive (OX, OptiBond XTR) were used. The shear bond strength (SBS) and shear fatigue strength (FS) of the enamel and dentin were obtained with and without phosphoric acid pre-etching prior to application of the adhesives. The specimens were stored in distilled water at 37 °C for 24 h, 6 months, and one year. A staircase method was used to determine the FS using a frequency of 10 Hz for 50,000 cycles or until failure occurred. The SBS and FS of enamel bonds were significantly higher with pre-etching, when compared to no pre-etching for the same water storage period. The FS of dentin bonds with pre-etching tended to decrease relative to no pre-etching at the same storage period. For the one year storage period, SU and GB with pre-etching showed significantly lower FS values than the groups without pre-etching. The influence of water storage on FS of the self-etch adhesives was dependent on the adhesive material, storage period and phosphoric acid pre-etching of the bonding site. Phosphoric acid pre-etching of enamel improves the effectiveness of self-etch adhesive systems. Inadvertent contact of phosphoric acid on dentin appears to reduce the ability of self-etch adhesives to effectively bond resin composite materials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Strength Training for Middle- and Long-Distance Performance: A Meta-Analysis.

    Science.gov (United States)

    Berryman, Nicolas; Mujika, Inigo; Arvisais, Denis; Roubeix, Marie; Binet, Carl; Bosquet, Laurent

    2018-01-01

    To assess the net effects of strength training on middle- and long-distance performance through a meta-analysis of the available literature. Three databases were searched, from which 28 of 554 potential studies met all inclusion criteria. Standardized mean differences (SMDs) were calculated and weighted by the inverse of variance to calculate an overall effect and its 95% confidence interval (CI). Subgroup analyses were conducted to determine whether the strength-training intensity, duration, and frequency and population performance level, age, sex, and sport were outcomes that might influence the magnitude of the effect. The implementation of a strength-training mesocycle in running, cycling, cross-country skiing, and swimming was associated with moderate improvements in middle- and long-distance performance (net SMD [95%CI] = 0.52 [0.33-0.70]). These results were associated with improvements in the energy cost of locomotion (0.65 [0.32-0.98]), maximal force (0.99 [0.80-1.18]), and maximal power (0.50 [0.34-0.67]). Maximal-force training led to greater improvements than other intensities. Subgroup analyses also revealed that beneficial effects on performance were consistent irrespective of the athletes' level. Taken together, these results provide a framework that supports the implementation of strength training in addition to traditional sport-specific training to improve middle- and long-distance performance, mainly through improvements in the energy cost of locomotion, maximal power, and maximal strength.

  9. The influence of perceived characteristics of management development programs on employee outcomes.

    NARCIS (Netherlands)

    Ardts, J.C.A.; van der Velde, M.E.G.; Maurer, T.

    2010-01-01

    Employees’ perceptions of Management Development (MD) programs is the topic of this study. The purpose is to examine the influence of three important perceived characteristics of MD programs on relevant MD outcomes. The MD characteristics are: availability of role models, perceived control, and

  10. Impact of Burnout on Organizational Outcomes, the Influence of Legal Demands: The Case of Ecuadorian Physicians

    Directory of Open Access Journals (Sweden)

    Paola Ochoa

    2018-05-01

    Full Text Available Interest in burnout has developed extensively worldwide, but there is scarce the literature regarding the consequences that new legal demands have on burnout and on organizational outcomes in physicians. The global context of the medical profession has been characterized in the recent years by changes in the employment patterns, profound intensification of work, and increment of labor flexibility. In this context, the study aims to analyze the influence of burnout on organizational outcomes in physicians, depending on new legal demands perception in Ecuador. Regarding the method, the research was cross sectional and in the first stage, studied the psychometric characteristics, validity and reliability of the instrument to assess burnout through a series of confirmatory factor analyses (CFA. In a second part, we assessed, the robustness of the model of causal relations between the burnout dimensions and organizational outcomes. We carried out a series of path analysis, structural equation model. The study was accomplished in five hospitals and the sample was incidental, comprising 435 physicians from Ecuador. We divided the group in two subcategories, Sample A, composed by participants that considered that new Criminal Code (COIP affects them and the Sample B, the group of physicians who believed that the COIP does not affect them. Burnout was assessed with the Spanish adaptation of the Maslach Burnout Inventory (MBI, the Organizational outcomes were measured with a seven-item self-report questionnaire, and we included an item regarding to the influence of new Criminal Code. We formulated four hypotheses, that considered that physicians who believed that the COIP affect them experience a greater negative influence of burnout on organizational outcomes. The results indicated that the group of physicians who believed that the COIP affects them (Sample A experienced a greater negative influence of cynicism on productivity than Sample B. Moreover

  11. Impact of Burnout on Organizational Outcomes, the Influence of Legal Demands: The Case of Ecuadorian Physicians.

    Science.gov (United States)

    Ochoa, Paola

    2018-01-01

    Interest in burnout has developed extensively worldwide, but there is scarce the literature regarding the consequences that new legal demands have on burnout and on organizational outcomes in physicians. The global context of the medical profession has been characterized in the recent years by changes in the employment patterns, profound intensification of work, and increment of labor flexibility. In this context, the study aims to analyze the influence of burnout on organizational outcomes in physicians, depending on new legal demands perception in Ecuador. Regarding the method, the research was cross sectional and in the first stage, studied the psychometric characteristics, validity and reliability of the instrument to assess burnout through a series of confirmatory factor analyses (CFA). In a second part, we assessed, the robustness of the model of causal relations between the burnout dimensions and organizational outcomes. We carried out a series of path analysis, structural equation model. The study was accomplished in five hospitals and the sample was incidental, comprising 435 physicians from Ecuador. We divided the group in two subcategories, Sample A, composed by participants that considered that new Criminal Code (COIP) affects them and the Sample B, the group of physicians who believed that the COIP does not affect them. Burnout was assessed with the Spanish adaptation of the Maslach Burnout Inventory (MBI), the Organizational outcomes were measured with a seven-item self-report questionnaire, and we included an item regarding to the influence of new Criminal Code. We formulated four hypotheses, that considered that physicians who believed that the COIP affect them experience a greater negative influence of burnout on organizational outcomes. The results indicated that the group of physicians who believed that the COIP affects them (Sample A) experienced a greater negative influence of cynicism on productivity than Sample B. Moreover, the lack of

  12. Effect of concrete strength gradation to the compressive strength of graded concrete, a numerical approach

    Science.gov (United States)

    Pratama, M. Mirza Abdillah; Aylie, Han; Gan, Buntara Sthenly; Umniati, B. Sri; Risdanareni, Puput; Fauziyah, Shifa

    2017-09-01

    Concrete casting, compacting method, and characteristic of the concrete material determine the performance of concrete as building element due to the material uniformity issue. Previous studies show that gradation in strength exists on building member by nature and negatively influence the load carrying capacity of the member. A pilot research had modeled the concrete gradation in strength with controllable variable and observed that the weakest material determines the strength of graded concrete through uniaxial compressive loading test. This research intends to confirm the recent finding by a numerical approach with extensive variables of strength disparity. The finite element analysis was conducted using the Strand7 nonlinear program. The results displayed that the increase of strength disparity in graded concrete models leads to the slight reduction of models strength. A substantial difference in displacement response is encountered on the models for the small disparity of concrete strength. However, the higher strength of concrete mix in the graded concrete models contributes to the rise of material stiffness that provides a beneficial purpose for serviceability of building members.

  13. Influence of Cognitive Ability on Therapy Outcomes for Anomia in Adults with Chronic Poststroke Aphasia

    Science.gov (United States)

    Dignam, Jade; Copland, David; O'Brien, Kate; Burfein, Penni; Khan, Asaduzzaman; Rodriguez, Amy D.

    2017-01-01

    Purpose: The relationship between cognitive abilities and aphasia rehabilitation outcomes is complex and remains poorly understood. This study investigated the influence of language and cognitive abilities on anomia therapy outcomes in adults with aphasia. Method: Thirty-four adults with chronic aphasia participated in Aphasia Language Impairment…

  14. Polysialates binders preparation and their influence to shear strength of foundry sand mixtures

    Directory of Open Access Journals (Sweden)

    R. Fridrich

    2008-07-01

    Full Text Available This paper deals with polysialates water-glasses preparation. There were used various procedures with the goal to create inorganic polymer on silicon and aluminum base. The one composed of SiO2 and AlO4 tetrahedron chains. For the preparation was concentrated NaOH solution used together with metakaolinite in a way low-temperature synthesis in the presence of alkaline silicate: higher pressure and temperature (autoclave to direct making of alkaline silicate made of sand, NaOH with metakaolinite addition and by melting fritted glass together with metakaolinite and dissolution in autoclave. The dissolving effectivity was evaluated by the concentration of aluminum in alkaline silicate and by the influence to reduce strengths after heat exposition with this inorganic binder.

  15. Preoperative opioid strength may not affect outcomes of anterior cervical procedures: a post hoc analysis of 2 prospective, randomized trials

    Science.gov (United States)

    Kelly, Michael P.; Anderson, Paul A.; Sasso, Rick C.; Riew, K. Daniel

    2015-01-01

    Object The aim of this study is to evaluate the relationship between preoperative opioid strength and outcomes of anterior cervical decompressive surgery. Methods A retrospective cohort of 1004 patients enrolled in 1 of 2 investigational device exemption studies comparing cervical total disc arthroplasty (TDA) and anterior cervical discectomy and fusion (ACDF) for single-level cervical disease causing radiculopathy or myelopathy was selected. At a preoperative visit, opioid use data, Neck Disability Index (NDI) scores, 36-ltem Short-Form Health Survey (SF-36) scores, and numeric rating scale scores for neck and arm pain were collected. Patients were divided into strong (oxycodone/morphine/meperidine), weak (codeine/propoxyphene/ hydrocodone), and opioid-naïve groups. Preoperative and postoperative (24 months) outcomes scores were compared within and between groups using the paired t-test and ANCOVA, respectively. Results Patients were categorized as follows: 226 strong, 762 weak, and 16 opioid naïve. The strong and weak groups were similar with respect to age, sex, race, marital status, education level, Worker's Compensation status, litigation status, and alcohol use. At 24-month follow-up, no differences in change in arm or neck pain scores (arm: strong –52.3, weak –50.6, naïve –54.0, p = 0.244; neck: strong –52.7, weak –50.8, naïve –44.6, p = 0.355); NDI scores (strong –36.0, weak –33.3, naïve –32.3, p = 0.181); or SF-36 Physical Component Summary scores (strong: 14.1, weak 13.3, naïve 21.7, p = 0.317) were present. Using a 15-point improvement in NDI to determine success, the authors found no between-groups difference in success rates (strong 80.6%, weak 82.7%, naïve 73.3%, p = 0.134). No difference existed between treatment arms (TDA vs ACDF) for any outcome at any time point. Conclusions Preoperative opioid strength did not adversely affect outcomes in this analysis. Careful patient selection can yield good results in this patient

  16. Impact of Hydrodynamics on Oral Biofilm Strength

    NARCIS (Netherlands)

    Paramonova, E.; Kalmykowa, O. J.; van der Mei, H. C.; Busscher, H. J.; Sharma, P. K.

    2009-01-01

    Mechanical removal of oral biofilms is ubiquitously accepted as the best way to prevent caries and periodontal diseases. Removal effectiveness strongly depends on biofilm strength. To investigate the influence of hydrodynamics on oral biofilm strength, we grew single- and multi-species biofilms of

  17. The influence of flame hardening process to aluminum 7075 series on the mechanical strength and micro structure

    Science.gov (United States)

    Koin, Sudibtia Titio; Triyono, Teguh; Surojo, Eko

    2018-02-01

    The 7075 series alloys are heat treatable wrought aluminum alloys based on the Al-Zn-Mg(-Cu) system. They are widely used in high-performance structural aerospace and transportation applications. Apart from compositional, casting and thermo-mechanical processing effects, the balance of properties is also significantly influenced by the way in which the materials are heat-treated. This paper describes the effect of flame hardening process to aluminum 7075 series on the increasing hardness, tensile strength, and evolution of microstructure. A test specimen had made by machining process and flame heating. Temperature of solution heat treatment is varied on 350 °C, 400 °C, 450 °C and 500 °C. After that process a test specimen would be quenched at nitrate-nitrite liquid during 45 minutes and artificial aging at 120°C until two days. The testing specimen consist of hardness and tensile strength according to ASTM. The result showed that specimen had precipitation on microstructure lead to an increase in aluminum properties. On the temperature 450°C solution heat treatment, the aluminum properties reached the highest value, namely, hardness of 129 HVN and tensile strength 570 MPa.

  18. Reactive Strength Index: A Poor Indicator of Reactive Strength?

    Science.gov (United States)

    Healy, Robin; Kenny, Ian; Harrison, Drew

    2017-11-28

    The primary aim was to assess the relationships between reactive strength measures and associated kinematic and kinetic performance variables achieved during drop jumps. A secondary aim was to highlight issues with the use of reactive strength measures as performance indicators. Twenty eight national and international level sprinters, consisting of fourteen men and women, participated in this cross-sectional analysis. Athletes performed drop jumps from a 0.3 m box onto a force platform with dependent variables contact time (CT), landing time (TLand), push-off time (TPush), flight time (FT), jump height (JH), reactive strength index (RSI, calculated as JH / CT), reactive strength ratio (RSR, calculated as FT / CT) and vertical leg spring stiffness (Kvert) recorded. Pearson's correlation test found very high to near perfect relationships between RSI and RSR (r = 0.91 to 0.97), with mixed relationships found between RSI, RSR and the key performance variables, (Men: r = -0.86 to -0.71 between RSI/RSR and CT, r = 0.80 to 0.92 between RSI/RSR and JH; Women: r = -0.85 to -0.56 between RSR and CT, r = 0.71 between RSI and JH). This study demonstrates that the method of assessing reactive strength (RSI versus RSR) may be influenced by the performance strategies adopted i.e. whether an athlete achieves their best reactive strength scores via low CTs, high JHs or a combination. Coaches are advised to limit the variability in performance strategies by implementing upper and / or lower CT thresholds to accurately compare performances between individuals.

  19. Influence of local surface texture by tool impression on the self piercing\\ud riveting process and the static lap shear strength

    OpenAIRE

    Li, Dezhi

    2017-01-01

    To increase fuel efficiency and reduce emission, aluminium alloys have been increasingly used in automotive body-in-white structures for lightweighting. Due to its advantages over some of the more traditional joining technologies, self-piercing riveting (SPR) has been widely used for these lightweight structures. Research has showed that friction is a very important factor that influences both the riveting process and joint strength for SPR, but these influences have not been fully understood...

  20. Side effects as influencers of treatment outcome.

    Science.gov (United States)

    Sharif, Zafar

    2008-01-01

    Research relative to the efficacy of a therapeutic agent commands a clinician's greatest interest, but treatment decisions are made based on optimizing efficacy and tolerability/safety considerations. Second-generation atypical antipsychotic drugs are a study in the importance of taking a careful look at the full benefit-risk profile of each drug. The disorders that atypical antipsychotics are approved to treat--schizophrenia, schizoaffective disorder, and bipolar disorder--are associated with an increased rate of certain medical comorbidities compared to the general population. Between-drug differences in efficacy are relatively modest for the atypicals, or between atypicals and conventionals, while differences in safety and tolerability are larger and more clinically relevant. The current article will provide a brief summary of safety-related issues that influence treatment outcome and choice of drug.

  1. Influence of nanoparticles on color stability, microhardness, and flexural strength of acrylic resins specific for ocular prosthesis.

    Science.gov (United States)

    Andreotti, Agda Marobo; Goiato, Marcelo Coelho; Moreno, Amália; Nobrega, Adhara Smith; Pesqueira, Aldiéris Alves; dos Santos, Daniela Micheline

    2014-01-01

    The aim of this study was to assess the effect of adding nanoparticles to N1 acrylic resin intended for artificial sclera, in terms of the color stability, microhardness, and flexural strength of the resin. Three hundred samples of N1 acrylic resin were used: 100 samples for color stability and microhardness tests (each test was performed on the opposite side of each sample), and 200 samples for flexural strength testing (100 samples before and after 1,008 hours of accelerated aging). Samples for each test were separated into ten groups (n=10), ie, without nanoparticles (control group) or with nanoparticles of zinc oxide, titanium dioxide (TiO₂), and barium sulfate at weight concentrations of 1%, 2%, and 2.5% (nanoparticle groups). Data were subjected to statistical analysis with nested analysis of variance and Tukey's test (P<0.05 significance level). Among the nanoparticle groups, the TiO₂ groups showed better color stability at all concentrations. Microhardness values increased after artificial aging, except for the control and zinc oxide groups. After aging, the 1%-2% TiO₂ groups had significantly higher microhardness values compared with the other nanoparticle groups. Before aging, there was a significant difference in flexural strength between the control and nanoparticle groups. After aging, the control and TiO₂ groups, regardless of concentration, showed the lowest flexural strength values. Incorporation of nanoparticles directly influenced the acrylic resin properties, with TiO₂ being the most influential nanoparticle in terms of the evaluated properties.

  2. Can a soda-lime glass be used to demonstrate how patterns of strength dependence are influenced by pre-cementation and resin-cementation variables?

    LENUS (Irish Health Repository)

    Hooi, Paul

    2013-01-01

    To determine how the variability in biaxial flexure strength of a soda-lime glass analogue for a PLV and DBC material was influenced by precementation operative variables and following resin-cement coating.

  3. Burst strength of tubing and casing based on twin shear unified strength theory.

    Science.gov (United States)

    Lin, Yuanhua; Deng, Kuanhai; Sun, Yongxing; Zeng, Dezhi; Liu, Wanying; Kong, Xiangwei; Singh, Ambrish

    2014-01-01

    The internal pressure strength of tubing and casing often cannot satisfy the design requirements in high pressure, high temperature and high H2S gas wells. Also, the practical safety coefficient of some wells is lower than the design standard according to the current API 5C3 standard, which brings some perplexity to the design. The ISO 10400: 2007 provides the model which can calculate the burst strength of tubing and casing better than API 5C3 standard, but the calculation accuracy is not desirable because about 50 percent predictive values are remarkably higher than real burst values. So, for the sake of improving strength design of tubing and casing, this paper deduces the plastic limit pressure of tubing and casing under internal pressure by applying the twin shear unified strength theory. According to the research of the influence rule of yield-to-tensile strength ratio and mechanical properties on the burst strength of tubing and casing, the more precise calculation model of tubing-casing's burst strength has been established with material hardening and intermediate principal stress. Numerical and experimental comparisons show that the new burst strength model is much closer to the real burst values than that of other models. The research results provide an important reference to optimize the tubing and casing design of deep and ultra-deep wells.

  4. Teammates and social influence affect weight loss outcomes in a team-based weight loss competition.

    Science.gov (United States)

    Leahey, Tricia M; Kumar, Rajiv; Weinberg, Brad M; Wing, Rena R

    2012-07-01

    Team-based internet interventions are increasing in popularity as a way of promoting weight loss in large numbers of individuals. Given that social networks influence health behavior change, this study investigated the effects of teammates and social influence on individual weight loss during a team-based weight loss competition. Shape Up Rhode Island (SURI) 2009 was a 12-week online program open to adult residents of Rhode Island. Participants joined with a team and competed with other teams on weight loss and/or physical activity. Overweight/obese (OW/OB) individuals (N = 3,330; 76% female; age = 46.1 ± 10.8; BMI = 31.2 ± 5.3 kg/m(2)), representing 987 teams, completed the weight loss program. Multilevel modeling was used to examine whether weight loss clustered among teammates and whether percentage of teammates in the weight loss division and reported teammate influence on weight loss were associated with individual weight outcomes. OW/OB completers reported losing 4.2 ± 3.4% of initial body weight. Weight loss was similar among teammates (intraclass correlation coefficient (ICC) = 0.10, P social influence for weight loss were associated with greater percent weight loss (P's ≤ 0.002). Similarly, achieving a clinically significant (5%) weight loss tended to cluster within teams (ICC = 0.09; P social influence for weight loss were associated with increased likelihood of achieving a 5% weight loss (odds ratio (OR) = 1.06; OR = 1.20, respectively). These results suggest that teammates affect weight loss outcomes during a team-based intervention. Harnessing and maximizing teammate influence for weight loss may enhance weight outcomes in large-scale team-based programs.

  5. Influence of Fatigue on Tackling Ability in Rugby League Players: Role of Muscular Strength, Endurance, and Aerobic Qualities.

    Directory of Open Access Journals (Sweden)

    Tim J Gabbett

    Full Text Available This study investigated the influence of repeated high-intensity effort exercise on tackling ability in rugby league players, and determined the relationship between physical qualities and tackling ability under fatigued conditions in these athletes. Eleven semi-professional rugby league players underwent measurements of speed (10 m and 40 m sprint, upper-body strength (4 repetition maximum [RM] bench press and weighted chin-up, upper-body muscular endurance (body mass maximum repetition chin-up, body mass maximum repetition dips, lower-body strength (4RM squat, and estimated maximal aerobic power (multi-stage fitness test. Tackling ability was assessed using a standardized one-on-one tackling test, before, during, and following four bouts of repeated high-intensity effort (RHIE exercise. The relationship between physical qualities and fatigue-induced decrements in tackling ability were determined using Pearson product moment correlation coefficients. Each cycle of the RHIE protocol induced progressive reductions in tackling ability. A moderate reduction (Effect Size = ~-1.17 ± 0.60, -34.1 ± 24.3% in tackling ability occurred after the fourth cycle of the RHIE protocol. Players with greater relative lower-body strength (i.e. 4RM squat/kg had the best tackling ability under fatigued conditions (r = 0.72, p = 0.013. There were no significant relationships between tackling ability under fatigued conditions and any other physical quality. These findings suggest that lower-body strength protects against fatigue-induced decrements in tackling ability. The development of lower-body strength should be a priority to facilitate the development of robust tackling skills that are maintained under fatigue.

  6. Influence of friction stir welding process and tool parameters on strength properties of AA7075-T6 aluminium alloy joints

    International Nuclear Information System (INIS)

    Rajakumar, S.; Muralidharan, C.; Balasubramanian, V.

    2011-01-01

    The aircraft aluminium alloys generally present low weldability by traditional fusion welding process. The development of the friction stir welding has provided an alternative improved way of satisfactorily producing aluminium joints, in a faster and reliable manner. In this present work, the influence of process and tool parameters on tensile strength properties of AA7075-T 6 joints produced by friction stir welding was analysed. Square butt joints were fabricated by varying process parameters and tool parameters. Strength properties of the joints were evaluated and correlated with the microstructure, microhardness of weld nugget. From this investigation it is found that the joint fabricated at a tool rotational speed of 1400 rpm, welding speed of 60 mm/min, axial force of 8 kN, using the tool with 15 mm shoulder diameter, 5 mm pin diameter, 45 HRc tool hardness yielded higher strength properties compared to other joints.

  7. Influence of intrauterine and extrauterine growth on neurodevelopmental outcome of monozygotic twins

    Directory of Open Access Journals (Sweden)

    R.K. Reolon

    2008-08-01

    Full Text Available There have been indications that intrauterine and early extrauterine growth can influence childhood mental and motor function. The objective of the present study was to evaluate the influence of intrauterine growth restriction and early extrauterine head growth on the neurodevelopmental outcome of monozygotic twins. Thirty-six monozygous twin pairs were evaluated at the corrected age of 12 to 42 months. Intrauterine growth restriction was quantified using the fetal growth ratio. The effects of birth weight ratio, head circumference at birth and current head circumference on mental and motor outcomes were estimated using mixed-effect linear regression models. Separate estimates of the between (interpair and within (intrapair effects of each measure on development were thus obtained. Neurodevelopment was assessed with the Bayley Scales of Infant Development, 2nd edition, by a psychologist blind to the exposure. A standardized neurological examination was performed by a neuropediatrician who was unaware of the exposures under investigation. After adjustment, birth weight ratio and head circumference at birth were not associated with motor or mental outcomes. Current head circumference was associated with mental but not with motor outcomes. Only the intrapair twin effect was significant. An increase of 1 cm in current head circumference of one twin compared with the other was associated with 3.2 points higher in Mental Developmental Index (95%CI = 1.06-5.32; P < 0.03. Thus, no effect of intrauterine growth was found on cognition and only postnatal head growth was associated with cognition. This effect was not shared by the co-twin.

  8. 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.

  9. Influence of defects on axial fatigue strength of maraging steel specimens produced by additive manufacturing

    Directory of Open Access Journals (Sweden)

    Rigon Daniele

    2018-01-01

    Full Text Available Nowadays many materials such as steels, aluminium and titanium alloys can be realised by powder bed solutions melting subsequently powder layers by means of a laser or electron beam (Laser Beam Melting – LBM and Electron Beam Melting – EBM. The microstructure realised by layer-by-layer solidification having high cooling rate cannot be considered isotropic. Therefore, the mechanical properties could be influenced by the building direction. Regarding maraging steel, the study of the influence of the building direction and the heat treatment on the static and axial fatigue strength has been investigated in a previous contribution. A large scatter of the fatigue test results was found because of the presence of detrimental surface and subsurface defects. The aim of this contribution is to present additional axial fatigue test results of maraging steel characterized by different build orientation and providing an analysis of the defects observed at the crack initiation area of the fracture surface.

  10. Influence of field strength, coil type and image resolution on assessment of synovitis by unenhanced MRI - a comparison with contrast-enhanced MRI

    International Nuclear Information System (INIS)

    Eshed, Iris; Krabbe, Simon; Axelsen, Mette; Pedersen, Susanne Juhl; Oestergaard, Mikkel; Boeyesen, Pernille; Moeller, Jakob M.; Therkildsen, Flemming; Madsen, Ole Rintek

    2015-01-01

    To explore if the reliability of synovitis assessment by unenhanced MRI is influenced by different MRI field-strengths, coil types and image resolutions in RA patients. Forty-one RA patients and 12 healthy controls underwent hand MRI (wrist and 2 nd -5 th metacarpophalangeal joints) at 4 different field-strengths (0.23 T/0.6 T/1.5 T/3.0 T) on the same day. Seven protocols using a STIR sequence with different field-strengths, coils (flex coils/dedicated phased-array extremity coils) and resolution were applied and scored blindly for synovitis (OMERACT-RAMRIS method). A 1.5 T post-contrast T1-weighted sequence was used as gold standard reference. Fair-good agreement (ICC=0.38-0.72) between the standard reference and the different STIR protocols (best agreement with extremity coil and small voxel size at 1.5 T). The accuracy for presence/absence of synovitis was very high per person (0.80-1.0), and moderate-high per joint (0.63-0.85), whereas exact agreements on scores were moderate (0.50-0.66). The intrareader agreement (15 patients and 3 controls) on presence/absence of synovitis was very high (0.87-1.0). Unenhanced MRI using STIR sequence is only moderately reliable for assessing hand synovitis in RA, when contrast-enhanced MRI is considered the gold standard reference. Contrast injection, field strength and coil type influence synovitis assessment, and should be considered before performing MRI in clinical trials and practice. (orig.)

  11. The Influence of Contextual Factors on the Sustainability of Professional Development Outcomes

    Science.gov (United States)

    Sandholtz, Judith Haymore; Ringstaff, Cathy

    2016-01-01

    This study investigated how contextual factors influenced the sustainability of outcomes from a 3-year, state-funded professional development program that provided science assistance for K-2 teachers in small, rural school districts. The research used a case-study approach with a purposive sample of five elementary schools that varied in…

  12. Influence of sand to coarse aggregate ratio on the interfacial bond strength of steel fibers in concrete for nuclear power plant

    International Nuclear Information System (INIS)

    Kim, Jung Jin; Kim, Dong Joo; Kang, Su Tae; Lee, Jang Hwa

    2012-01-01

    Highlights: ► The final goal is to develop a fiber reinforced concrete for containment buildings. ► We investigated the effect of S/a on the bond strength of steel fibers. ► Deformed steel fibers produced much higher interfacial bond strength. ► As S/a increased, twisted fiber showed a significant enhancement in bond strength. ► Smooth and hooked fiber showed no clear difference as S/a increased. - Abstract: The interfacial bond strength of three high strength steel fibers (smooth, hooked, and twisted fiber) in concrete of nuclear power plants was investigated to develop fiber reinforced concrete for containment building. Sand to aggregate ratio (S/a) was adjusted to compensate reduction in the workability due to adding fibers; the influence of S/a ratio on the interfacial bond strength was investigated. As the S/a ratio increased from 0.444 to 0.615, the bond strength of twisted steel fiber was significantly improved while smooth and hooked steel fiber showed no clear difference. The different sensitivity according to the S/a ratio results from the different pullout mechanism: twisted steel fiber generates more mechanical interaction during fiber pullout at the interface between fiber and matrix than smooth and hooked fibers. The microscopic observation by scanning electron microscope back-scattered electrons images discovered lower porosity at the interfacial transition zone between fiber and concrete with higher S/a ratio.

  13. Influence of sand to coarse aggregate ratio on the interfacial bond strength of steel fibers in concrete for nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Jin, E-mail: jjinslow@nate.com [Department of Civil and Environmental Engineering, SeJong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Kim, Dong Joo, E-mail: djkim75@sejong.ac.kr [Department of Civil and Environmental Engineering, SeJong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747 (Korea, Republic of); Kang, Su Tae, E-mail: stkang@daegu.ac.kr [Department of Civil Engineering, Daegu University, 201 Daegudae-ro, Jillyang, Gyeongsan, Gyeongbuk 712-714 (Korea, Republic of); Lee, Jang Hwa, E-mail: jhlee@kict.re.kr [Korea Institute of Construction Technology, 2311 Daewha-Dong, Ilsan-Gu, Goyang-Si, Gyeonggi-Do 411-712 (Korea, Republic of)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer The final goal is to develop a fiber reinforced concrete for containment buildings. Black-Right-Pointing-Pointer We investigated the effect of S/a on the bond strength of steel fibers. Black-Right-Pointing-Pointer Deformed steel fibers produced much higher interfacial bond strength. Black-Right-Pointing-Pointer As S/a increased, twisted fiber showed a significant enhancement in bond strength. Black-Right-Pointing-Pointer Smooth and hooked fiber showed no clear difference as S/a increased. - Abstract: The interfacial bond strength of three high strength steel fibers (smooth, hooked, and twisted fiber) in concrete of nuclear power plants was investigated to develop fiber reinforced concrete for containment building. Sand to aggregate ratio (S/a) was adjusted to compensate reduction in the workability due to adding fibers; the influence of S/a ratio on the interfacial bond strength was investigated. As the S/a ratio increased from 0.444 to 0.615, the bond strength of twisted steel fiber was significantly improved while smooth and hooked steel fiber showed no clear difference. The different sensitivity according to the S/a ratio results from the different pullout mechanism: twisted steel fiber generates more mechanical interaction during fiber pullout at the interface between fiber and matrix than smooth and hooked fibers. The microscopic observation by scanning electron microscope back-scattered electrons images discovered lower porosity at the interfacial transition zone between fiber and concrete with higher S/a ratio.

  14. Influence of perfusion and ventilation scans on therapeutic decision making and outcome in cases of possible embolism

    International Nuclear Information System (INIS)

    Mercandetti, A.J.; Kipper, M.S.; Moser, K.M.

    1985-01-01

    The authors examined the influence of perfusion (Q) and ventilation (V) scans on therapeutic decision making and outcome among 229 patients referred for lung scans because embolism was suggested and found that specific V/Q scan patterns strongly influenced postscan decisions regarding initiation, maintenance or cessation of heparin therapy. These therapeutic decisions bore a relationship to outcome (recurrences and death) and disclosed decision-making deficits that need remedy by future investigational and educational efforts. 25 references, 5 tables

  15. The influence of interleukin-7 receptor α-chain haplotypes on outcome after allogeneic hematopoietic cell transplantation

    DEFF Research Database (Denmark)

    Broux, B; Shamim, Z; Wang, T

    2014-01-01

    We investigated the influence of IL-7 receptor α-chain (IL-7Rα) gene haplotypes in donors on the outcome of haematopoietic cell transplantation (HCT). Unlike the association between single donor SNPs and HCT outcome found previously, only trends towards association were found here, due to 'diluti...

  16. Influence of different crosshead speeds on diametral tensile strength of a methacrylate based resin composite: An in-vitro study.

    Science.gov (United States)

    Sood, Anubhav; Ramarao, Sathyanarayanan; Carounanidy, Usha

    2015-01-01

    The aim was to evaluate the influence of different crosshead speeds on diametral tensile strength (DTS) of a resin composite material (Tetric N-Ceram). The DTS of Tetric N-Ceram was evaluated using four different crosshead speeds 0.5 mm/min (DTS 1), 1 mm/min (DTS 2), 5 mm/min (DTS 3), 10 mm/min (DTS 4). A total of 48 specimens were prepared and divided into four subgroups with 12 specimens in each group. Specimens were made using stainless steel split custom molds of dimensions 6 mm diameter and 3 mm height. The specimens were stored in distilled water at room temperature for 24 h. Universal testing machine was used and DTS values were calculated in MPa. Analysis of variance was used to compare the four groups. Higher mean DTS value was recorded in DTS 2 followed by DTS 4, DTS 1, and DTS 3, respectively. However, the difference in mean tensile strength between the groups was not statistically significant (P > 0.05). The crosshead speed variation between 0.5 and 10 mm/min does not seem to influence the DTS of a resin composite.

  17. Influence of different adhesive systems on the pull-out bond strength of glass fiber posts.

    Science.gov (United States)

    da Silva, Luciana Mendonça; Andrade, Andréa Mello de; Machuca, Melissa Fernanda Garcia; da Silva, Paulo Maurício Batista; da Silva, Ricardo Virgolino C; Veronezi, Maria Cecília

    2008-01-01

    This in vitro study evaluated the tensile bond strength of glass fiber posts (Reforpost - Angelus-Brazil) cemented to root dentin with a resin cement (RelyX ARC - 3M/ESPE) associated with two different adhesive systems (Adper Single Bond - 3M/ESPE and Adper Scotchbond Multi Purpose (MP) Plus - 3M/ESPE), using the pull-out test. Twenty single-rooted human teeth with standardized root canals were randomly assigned to 2 groups (n=10): G1- etching with 37% phosphoric acid gel (3M/ESPE) + Adper Single Bond + #1 post (Reforpost - Angelus) + four #1 accessory posts (Reforpin - Angelus) + resin cement; G2- etching with 37% phosphoric acid gel + Adper Scotchbond MP Plus + #1 post + four #1 accessory posts + resin cement. The specimens were stored in distilled water at 37 degrees C for 7 days and submitted to the pull-out test in a universal testing machine (EMIC) at a crosshead speed of 0.5 mm/min. The mean values of bond strength (kgf) and standard deviation were: G1- 29.163 +/- 7.123; G2- 37.752 +/-13.054. Statistical analysis (Student's t-test; a=0.05 showed no statistically significant difference (pAdhesive bonding failures between resin cement and root canal dentin surface were observed in both groups, with non-polymerized resin cement in the apical portion of the post space when Single Bond was used (G1). The type of adhesive system employed on the fiber post cementation did not influence the pull-out bond strength.

  18. Influence of different adhesive systems on the pull-out bond strength of glass fiber posts

    Directory of Open Access Journals (Sweden)

    Luciana Mendonça da Silva

    2008-06-01

    Full Text Available This in vitro study evaluated the tensile bond strength of glass fiber posts (Reforpost - Angelus-Brazil cemented to root dentin with a resin cement (RelyX ARC - 3M/ESPE associated with two different adhesive systems (Adper Single Bond - 3M/ESPE and Adper Scotchbond Multi Purpose (MP Plus - 3M/ESPE, using the pull-out test. Twenty single-rooted human teeth with standardized root canals were randomly assigned to 2 groups (n=10: G1- etching with 37% phosphoric acid gel (3M/ESPE + Adper Single Bond + #1 post (Reforpost - Angelus + four #1 accessory posts (Reforpin - Angelus + resin cement; G2- etching with 37% phosphoric acid gel + Adper Scotchbond MP Plus + #1 post + four #1 accessory posts + resin cement. The specimens were stored in distilled water at 37°C for 7 days and submitted to the pull-out test in a universal testing machine (EMIC at a crosshead speed of 0.5 mm/min. The mean values of bond strength (kgf and standard deviation were: G1- 29.163 ± 7.123; G2- 37.752 ±13.054. Statistical analysis (Student's t-test; a=0.05 showed no statistically significant difference (p<0.05 between the groups. Adhesive bonding failures between resin cement and root canal dentin surface were observed in both groups, with non-polymerized resin cement in the apical portion of the post space when Single Bond was used (G1. The type of adhesive system employed on the fiber post cementation did not influence the pull-out bond strength.

  19. Species type controls root strength and influences slope stability in coastal Ecuador

    Science.gov (United States)

    Anttila, E.; Wray, M. E.; Knappe, E.; Ogasawara, T.; Tholt, A.; Cliffe, B.; Oshun, J.

    2014-12-01

    Tree roots, particular those of old growth trees, provide significant cohesive strength that can prevent shallow landslides. Little is known about the root strength of trees growing in dry tropical forests. In 1997, Bahía de Caráquez, Ecuador experienced a large landslide, which may have been precipitated by massive deforestation along the Ecuadorian coast. We used a tensile spring apparatus combined with root maps to caclulate the cohesive strength of different native species of trees. Whereas the results show the previously reported power law relationship between root diameter and tensile strength, our data also reveals new contributions. First, we find that trees have far stronger and more abundant roots than neighboring bushes, and thus add far more cohesive strength to the hillslope. Furthermore, there is a wide range of tensile strength among the native trees measured, with algarrobo having the strongest roots, and ceibo gernally being weak rooted. Finally, we use a slope stability model to predict failure conditions considering the strength added to a hillslope if vegetation is predominantly composed of bushes, algarrobo, or ceibo. Our results, which are the first of their kind for the Ecuadorian dry tropical forest, will be used to guide the ongoing native reforestation efforts of Global Student Embassy. Our unique partnership with Global Student Embassy connects our field study to practical land use decisions that will lead to increased slope and decreased human danger along coastal Ecuador's dry tropical forest.

  20. Optimism Moderates the Influence of Pain Catastrophizing on Shoulder Pain Outcome: A Longitudinal Analysis.

    Science.gov (United States)

    Coronado, Rogelio A; Simon, Corey B; Lentz, Trevor A; Gay, Charles W; Mackie, Lauren N; George, Steven Z

    2017-01-01

    Study Design Secondary analysis of prospectively collected data. Background An abundance of evidence has highlighted the influence of pain catastrophizing and fear avoidance on clinical outcomes. Less is known about the interaction of positive psychological resources with these pain-associated distress factors. Objective To assess whether optimism moderates the influence of pain catastrophizing and fear avoidance on 3-month clinical outcomes in patients with shoulder pain. Methods Data from 63 individuals with shoulder pain (mean ± SD age, 38.8 ± 14.9 years; 30 female) were examined. Demographic, psychological, and clinical characteristics were obtained at baseline. Validated measures were used to assess optimism (Life Orientation Test-Revised), pain catastrophizing (Pain Catastrophizing Scale), fear avoidance (Fear-Avoidance Beliefs Questionnaire physical activity subscale), shoulder pain intensity (Brief Pain Inventory), and shoulder function (Pennsylvania Shoulder Score function subscale). Shoulder pain and function were reassessed at 3 months. Regression models assessed the influence of (1) pain catastrophizing and optimism and (2) fear avoidance and optimism. The final multivariable models controlled for factors of age, sex, education, and baseline scores, and included 3-month pain intensity and function as separate dependent variables. Results Shoulder pain (mean difference, -1.6; 95% confidence interval [CI]: -2.1, -1.2) and function (mean difference, 2.4; 95% CI: 0.3, 4.4) improved over 3 months. In multivariable analyses, there was an interaction between pain catastrophizing and optimism (β = 0.19; 95% CI: 0.02, 0.35) for predicting 3-month shoulder function (F = 16.8, R 2 = 0.69, Poptimism lessened the influence of pain catastrophizing on function. There was no evidence of significant moderation of fear-avoidance beliefs for 3-month shoulder pain (P = .090) or function (P = .092). Conclusion Optimism decreased the negative influence of pain

  1. Does increased salinity influence the competitive outcome of two producer species?

    Science.gov (United States)

    Venâncio, C; Anselmo, E; Soares, A; Lopes, I

    2017-02-01

    Within the context of global climate changes, it is expected that low-lying coastal freshwater ecosystems will face seawater intrusion with concomitant increase in salinity levels. Increased salinity may provoke disruption of competitive relationships among freshwater species. However, species may be capable of acclimating to salinity, which, in turn, may influence the resilience of ecosystems. Accordingly, this work aimed at assessing the effects of multigenerational exposure to low levels of salinity in the competitive outcome of two species of green microalgae: Raphidocelis subcapitata and Chlorella vulgaris. To attain this, three specific objectives were delineated: (1) compare the toxicity of natural seawater (SW) and NaCl (as a surrogate of SW) to the two microalgae, (2) determine the capacity of the two microalgae species to acclimate to low salinity levels, and (3) assess the influence of exposure to low salinity levels in the competitive outcome of the two microalgae. Results revealed SW to be slightly less toxic than NaCl for the two microalgae. The EC 25,72 h for growth rate was 4.63 and 10.3 mS cm -1 for R. subcapitata and 6.94 and 15.4 mS cm -1 for C. vulgaris, respectively for NaCl and SW. Both algae were capable of acclimating to low levels of salinity, but C. vulgaris seemed to acclimate faster than R. subcapitata. When exposed in competition, under control conditions, the growth rates of C. vulgaris were lower than those of R. subcapitata. However, C. vulgaris was capable of acquiring competitive advantage equaling or surpassing the growth rate of R. subcapitata with the addition of NaCl or SW, respectively. The multigenerational exposure to low levels of salinity influenced the competitive outcome of the two algae both under control and salinity exposure. These results suggest that long-term exposure to low salinity stress can cause shifts in structure of algae communities and, therefore, should not be neglected since algae are at the basis

  2. The Stereotype-Matching Effect: Greater Influence on Functioning When Age Stereotypes Correspond to Outcomes

    Science.gov (United States)

    Levy, Becca R.; Leifheit-Limson, Erica

    2009-01-01

    Older individuals assimilate, and are targeted by, contradictory positive and negative age stereotypes. It was unknown whether the influence of stereotype valence is stronger when the stereotype content corresponds to the outcome domain. We randomly assigned older individuals to either positive-cognitive, negative-cognitive, positive-physical, or negative-physical subliminal-age-stereotype groups and assessed cognitive and physical outcomes. As predicted, when the age stereotypes corresponded to the outcome domains, their valence had a significantly greater impact on cognitive and physical performance. This suggests that if a match occurs, it is more likely to generate expectations that become self-fulfilling prophecies. PMID:19290757

  3. Influence of austenization temperature on microstructure and mechanical properties of a new ultra-high strength low alloyed steel

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Ya-Ya; Xu, Chi; Su, Xiang; Sun, Yu-Lin; Pan, Xi; Cao, Yue-De; Chen, Guang [Nanjing Univ. of Science and Technology, Nanjing (China). Engineering Research Center of Materials Behavior and Design

    2017-07-01

    The effects of austenization temperature on the microstructures and mechanical properties of a newly designed ultra-high strength low alloy martensitic steel were systematically studied. The microstructures of the martensitic steels which were quenched from different temperatures between 860 and 980 C were investigated by transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD) and discussed. The results showed that the martensite laths were found to coarsen slowly and the carbide precipitates dissolved gradually with increasing austenization temperature. As the austenization temperature increased from 860 to 980 C, the volume of retained austenite and the numerical ratio of high angle grain boundaries (HAGBs) were observed to increase while the numerical ratio of low angle grain boundaries (LAGBs) decreased. Rockwell C hardness (HRC), tensile strength and yield strength increased at first and then decreased, while impact toughness was greatly improved with increasing austenization temperature. The fracture mechanism was brittle fracture when austenitized at low temperatures, while it was ductile fracture when austenitized at high temperatures. The mechanical properties were significantly influenced by the formation of retained austenite, the dissolution of carbides, and the numerical ratio of HAGBs and LAGBs.

  4. Strength of bond with Comspan Opaque to three silicoated alloys and titanium.

    Science.gov (United States)

    Hansson, O

    1990-06-01

    In Sweden high-gold alloys or cobalt-chromium alloys are used for resin-bonded prostheses. The bond strength between a resin cement and different sandblasted or silicoated metals were measured before and after thermocycling; in connection with this some rapid thermocycling methods were studied. The effect of different storage times and different protection coatings on bond strength were tested. Finally, the influence of rubbing and contamination with saliva on bond strength were investigated. Silicoating increased the bond strength significantly. The highest bond strengths were these of silicoated Wirobond and titanium, unsusceptible to thermal stress; the bond strengths of the sandblasted metals were the weakest, and sensitive to thermocycling as well. The influence on bond strength for silicoated gold alloys, protected with an unpolymerized composite resin coating, stored in sealed plastic bags up to 7 days, was negligible. Rubbing and contamination with saliva did not influence bond strength. Preferably, silicoated Wirobond and titanium should be used for resin-bonded prostheses, but gold alloys may still be adequate for clinical use. The experimental method described for storing, sealing, and cleaning the silicoated metal surfaces in this article can be recommended for laboratory and clinical use.

  5. Memory strength and lineup presentation moderate effects of administrator influence on mistaken identifications.

    Science.gov (United States)

    Zimmerman, David M; Chorn, Jacqueline Austin; Rhead, Lindsey M; Evelo, Andrew J; Kovera, Margaret Bull

    2017-12-01

    Administrator/witness pairs (N = 313) were randomly assigned to target-absent lineups in a 2 (Suspect/Perpetrator Similarity: High Suspect Similarity vs. Low Suspect Similarity) × 2 (Retention Interval: 30 min vs. 1 week) × 2 (Lineup Presentation: Simultaneous vs. Sequential) × 2 (Administrator Knowledge: Single-Blind vs. Double-Blind) factorial design to test whether suspect similarity and memory strength constrain interpersonal expectancy effects on eyewitness identification accuracy. Administrators who knew which lineup member was the suspect (single-blind) or who administered simultaneous lineups were more likely to emit verbal and nonverbal behaviors that suggested to the witness who the suspect was. Additionally, single-blind administrators exerted more pressure on witnesses to choose the suspect as opposed to fillers. Administrator knowledge interacted with retention interval and lineup presentation to influence mistaken identifications of innocent suspects; witnesses were more likely to mistakenly identify an innocent suspect from single-blind than double-blind lineups when witness retention intervals were long and photographs were presented simultaneously. Contrary to our predictions, suspect/perpetrator similarity did not interact with other manipulated variables to influence identification decisions. Both sequential and double-blind procedures should be used to reduce the use of suggestive behavior during lineup administration. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Influence of Sulfate-Reducing Bacteria on the Corrosion Residual Strength of an AZ91D Magnesium Alloy

    Science.gov (United States)

    Zhu, Xianyong; Liu, Yaohui; Wang, Qiang; Liu, Jiaan

    2014-01-01

    In this paper, the corrosion residual strength of the AZ91D magnesium alloy in the presence of sulfate-reducing bacteria is studied. In the experiments, the chemical composition of corrosion film was analyzed by a scanning electron microscope with energy dispersive X-ray spectroscopy. In addition, a series of instruments, such as scanning electronic microscope, pH-meter and an AG-10TA materials test machine, were applied to test and record the morphology of the corrosion product, fracture texture and mechanical properties of the AZ91D magnesium alloy. The experiments show that the sulfate-reducing bacteria (SRB) play an important role in the corrosion process of the AZ91D magnesium alloy. Pitting corrosion was enhanced by sulfate-reducing bacteria. Corrosion pits are important defects that could lead to a significant stress concentration in the tensile process. As a result, sulfate-reducing bacteria influence the corrosion residual strength of the AZ91D magnesium alloy by accelerating pitting corrosion. PMID:28788236

  7. Academic season does not influence cardiac surgical outcomes at US Academic Medical Centers.

    Science.gov (United States)

    Lapar, Damien J; Bhamidipati, Castigliano M; Mery, Carlos M; Stukenborg, George J; Lau, Christine L; Kron, Irving L; Ailawadi, Gorav

    2011-06-01

    Previous studies have demonstrated the influence of academic season on outcomes in select surgical populations. However, the influence of academic season has not been evaluated nationwide in cardiac surgery. We hypothesized that cardiac surgical outcomes were not significantly influenced by time of year at both cardiothoracic teaching hospitals and non-cardiothoracic teaching hospitals nationwide. From 2003 to 2007, a weighted 1,614,394 cardiac operations were evaluated using the Nationwide Inpatient Sample database. Patients undergoing cardiac operations at cardiothoracic teaching and non-cardiothoracic teaching hospitals were identified using the Association of American Medical College's Graduate Medical Education Tracking System. Hierarchic multivariable logistic regression analyses were used to estimate the effect of academic quarter on risk-adjusted outcomes. Mean patient age was 65.9 ± 10.9 years. Women accounted for 32.8% of patients. Isolated coronary artery bypass grafting was the most common operation performed (64.7%), followed by isolated valve replacement (19.3%). The overall incidence of operative mortality and composite postoperative complication rate were 2.9% and 27.9%, respectively. After accounting for potentially confounding risk factors, timing of operation by academic quarter did not independently increase risk-adjusted mortality (p = 0.12) or morbidity (p = 0.24) at academic medical centers. Risk-adjusted mortality and morbidity for cardiac operations were not associated with time of year in the US at teaching and nonteaching hospitals. Patients should be reassured of the safety of performance of cardiac operations at academic medical centers throughout a given academic year. Copyright © 2011 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  8. The Influence of High Drug Loading in Xanthan Tablets and Media with Different Physiological pH and Ionic Strength on Swelling and Release.

    Science.gov (United States)

    Mikac, Urša; Sepe, Ana; Baumgartner, Saša; Kristl, Julijana

    2016-03-07

    The formation of a gel coat around xanthan (Xan) tablets, empty or loaded with pentoxifylline (PF), and its release in media differing in pH and ionic strength by NMR, MR imaging, and two release methods were studied. The T1 and T2 NMR relaxation times in gels depend predominantly on Xan concentration; the presence of PF has negligible influence on them. It is interesting that the matrix swelling is primarily regulated by Xan despite high drug loading (25%, 50%). The gastric pH and high ionic strength of the media do not influence the position of the penetration and swelling fronts but do affect the erosion front and gel thickness. The different release profiles obtained in mixing and nonmixing in vitro methods are the consequence of matrix hydration level and erosion at the surface. In water and in diluted acid medium with low ionic strength, the main release mechanism is erosion, whereas in other media (pH 1.2, μ ≥ 0.20 M), anomalous transport dominates as was found out by fitting of measured data with theoretical model. Besides the in vitro investigation that mimics gastric conditions, mathematical modeling makes the product development more successful.

  9. CHARACTERIZATION AND PERFORMANCE OF ELEMENTARY HEMP FIBRES: FACTORS INFLUENCING TENSILE STRENGTH

    Directory of Open Access Journals (Sweden)

    Mizi Fan

    2010-09-01

    Full Text Available This paper presents the outcomes from an extensive investigation on the structure and geometry of single hemp fibres, as well as configurations and related tensile strength (TS of hemp fibres, with the aid of field emission scanning and optical microscopy. The results showed that 1 the TS increased with the decrease of the diameter of individual test pieces, due possibly to the stacks of multiple single fibres within the test pieces; 2 shear failure between single fibres in a test pieces played a significant role in the test results; 3 the TS was closely related to the number of both the inherent joints along the fibre length and single fibres contained in the test pieces; 4 the splits along the length and width of hemp fibres may complicate the test results, and 5 the optimized treatment prior to decortications may double the TS of hemp fibres compared to a normal retting processing. Reliable TS of single hemp fibres have been derived by a power regression, and the predicted TS were verified with an excellent agreement with experimentally tested results. The tensile strain-stress plot was found to be linear for all hemp test pieces, showing that the behaviour of single hemp fibres obeys Hooke’s law.

  10. Mind-Body Interventions to Reduce Risk for Health Disparities Related to Stress and Strength Among African American Women: The Potential of Mindfulness-Based Stress Reduction, Loving-Kindness, and the NTU Therapeutic Framework.

    Science.gov (United States)

    Woods-Giscombé, Cheryl L; Black, Angela R

    2010-12-14

    In the current article, the authors examine the potential role of mind-body interventions for preventing or reducing health disparities in a specific group-African American women. The authors first discuss how health disparities affect this group, including empirical evidence regarding the influence of biopsychosocial processes (e.g., psychological stress and social context) on disparate health outcomes. They also detail how African American women's unique stress experiences as a result of distinct sociohistorical and cultural experiences related to race and gender potentially widen exposure to stressors and influence stress responses and coping behaviors. Using two independent, but related, frameworks (Superwoman Schema [SWS] and the Strong Black Woman Script [SBW-S]), they discuss how, for African American women, stress is affected by "strength" (vis-à-vis resilience, fortitude, and self-sufficiency) and the emergent health-compromising behaviors related to strength (e.g., emotional suppression, extraordinary caregiving, and self-care postponement). The authors then describe the potential utility of three mind-body interventions-mindfulness-based stress reduction (MBSR), loving-kindness meditation (LKM), and NTU psychotherapy-for specifically targeting the stress-, strength-, and contextually related factors that are thought to influence disparate outcomes for African American women. Self-awareness, self-care, inter- and intrapersonal restorative healing and a redefinition of inner strength may manifest through developing a mindfulness practice to decrease stress-related responses; using LKM to cultivate compassion and forgiveness for self and others; and the balance of independence and interdependence as a grounding NTU principle for redefining strength. The authors conclude with a discussion of potential benefits for integrating key aspects of the interventions with recommendations for future research.

  11. Influence of chlorhexidine concentration on microtensile bond strength of contemporary adhesive systems

    Directory of Open Access Journals (Sweden)

    Edson Alves de Campos

    2009-09-01

    Full Text Available The purpose of this study was to investigate the influence of chlorhexidine (CHX concentration on the microtensile bond strength (μTBS of contemporary adhesive systems. Eighty bovine central incisors were used in this study. The facial enamel surface of the crowns was abraded with 600-grit silicon carbide paper to expose flat, mid-coronal dentin surfaces. The tested materials were Scotchbond Multipurpose (SMP, Single-Bond (SB, Clearfil SE Bond (CSEB and Clearfil Tri S Bond (CTSB. All the materials were applied according to manufacturer's instructions and followed by composite application (Z250. The teeth were randomly divided into 16 groups: for the etch-and-rinse adhesives (SMP and SB, 0.12% or 2% CHX was applied prior to or after the acid etching procedure. For the self-etch adhesives (CSEB and CTSB 0.12% or 2% CHX was applied prior to the primer. Control groups for each one of the adhesive systems were also set up. The specimens were immediately submitted to μTBS testing and the data were analyzed using Analysis of Variance and the Tukey post hoc test (alpha = .01. The failure patterns of the specimens were observed using scanning electron microscopy. The effects of 2% CHX were statistically significant (p < 0.01 for the self-etch adhesives but were not significant for the etch-and-rinse adhesive systems. Analysis of the data demonstrated no statistical difference between the etch-and-rinse adhesive systems. CHX-based cavity disinfectants in concentrations higher than 0.12% should be avoided prior to the self-etch adhesive systems evaluated in this study to diminish the possibilities of reduction in bond strength.

  12. Influence of Heat-Treatment on the Adhesive Strength between a Micro-Sized Bonded Component and a Silicon Substrate under Bend and Shear Loading Conditions

    International Nuclear Information System (INIS)

    Ishiyama, Chiemi

    2012-01-01

    Adhesive bend and shear tests of micro-sized bonded component have been performed to clarify the relationship between effects of heat-treatment on the adhesive strength and the bonded specimen shape using Weibull analysis. Multiple micro-sized SU-8 columns with four different diameters were fabricated on a Si substrate under the same fabrication condition. Heat-treatment can improve both of the adhesive bend and shear strength. The improvement rate of the adhesive shear strength is much larger than that of the adhesive bend strength, because the residual stress, which must change by heat-treatment, should effect more strongly on the shear loading. In case of bend type test, the adhesive bend strength in the smaller diameters (50 and 75 μm) widely vary, because the critical size of the natural defect (micro-crack) should vary more widely in the smaller diameters. In contrast, in case of shear type test, the adhesive shear strengths in each diameter of the columns little vary. This suggests that the size of the natural defects may not strongly influence on the adhesive shear strength. All the result suggests that both of the adhesive bend and shear strengths should be complicatedly affected by heat-treatment and the bonded columnar diameter

  13. The Influence of Resistance Training Experience on the Between-Day Reliability of Commonly Used Strength Measures in Male Youth Athletes.

    Science.gov (United States)

    Weakley, Jonathon J S; Till, Kevin; Darrall-Jones, Joshua; Roe, Gregory A B; Phibbs, Padraic J; Read, Dale B; Jones, Ben L

    2017-07-01

    Weakley, JJS, Till, K, Darrall-Jones, J, Roe, GAB, Phibbs, PJ, Read, DB, and Jones, BL. The influence of resistance training experience on the between-day reliability of commonly used strength measures in male youth athletes. J Strength Cond Res 31(7): 2005-2010, 2017-The purpose of this study was to determine the between-day reliability of commonly used strength measures in male youth athletes while considering resistance training experience. Data were collected on 25 male athletes over 2 testing sessions, with 72 hours rest between, for the 3 repetition maximum (3RM) front squat, chin-up, and bench press. Subjects were initially categorized by resistance training experience (inexperienced; 6-12 months, experienced; >2 years). The assessment of the between-day reliability (coefficient of variation [CV%]) showed that the front squat (experienced: 2.90%; inexperienced: 1.90%), chin-up (experienced: 1.70%; inexperienced: 1.90%), and bench press (experienced: 4.50%; inexperienced: 2.40%) were all reliable measures of strength in both groups. Comparison between groups for the error of measurement for each exercise showed trivial differences. When both groups were combined, the CV% for the front squat, bench press, and chin-up were 2.50, 1.80, and 3.70%, respectively. This study provides scientists and practitioners with the between-day reliability reference data to determine real and practical changes for strength in male youth athletes with different resistance training experience. Furthermore, this study demonstrates that 3RM front squat, chin-up, and bench press are reliable exercises to quantify strength in male youth athletes.

  14. Can Quantitative Muscle Strength and Functional Motor Ability Differentiate the Influence of Age and Corticosteroids in Ambulatory Boys with Duchenne Muscular Dystrophy?

    Science.gov (United States)

    Buckon, Cathleen; Sienko, Susan; Bagley, Anita; Sison-Williamson, Mitell; Fowler, Eileen; Staudt, Loretta; Heberer, Kent; McDonald, Craig M; Sussman, Michael

    2016-07-08

    In the absence of a curative treatment for Duchenne Muscular Dystrophy (DMD), corticosteroid therapy (prednisone, deflazacort) has been adopted as the standard of care, as it slows the progression of muscle weakness and enables longer retention of functional mobility. The ongoing development of novel pharmacological agents that target the genetic defect underlying DMD offer hope for a significant alteration in disease progression; however, substantiation of therapeutic efficacy has proved challenging. Identifying functional outcomes sensitive to the early, subtle changes in muscle function has confounded clinical trials. Additionally, the alterations in disease progression secondary to corticosteroid therapy are not well described making it difficult to ascertain the benefits of novel agents, often taken concurrently with corticosteroids. The purpose of this study was to examine outcome responsiveness to corticosteroid therapy and age at the onset of a natural history study of ambulatory boys with DMD. Eighty-five ambulatory boys with DMD (mean age 93 mo, range 49 to 180 mo) were recruited into this study. Fifty participants were on corticosteroid therapy, while 33 were corticosteroid naïve at the baseline assessment. Within each treatment group boys were divided in two age groups, 4 to 7 years and 8 and greater years of age. The Biodex System 3 Pro isokinetic dynamometer was used to assess muscle strength. Motor skills were assessed using the upper two dimensions (standing/walking, running & jumping) of the Gross Motor Function Measure (GMFM 88) and Timed Motor Tests (TMTs) (10-meter run, sit to stand, supine to stand, climb 4-stairs). Two way analysis of variance and Pearson correlations were used for analysis. A main effect for age was seen in select lower extremity muscle groups (hip flexors, knee extensors and ankle dorsiflexors), standing dimension skills, and all TMTs with significantly greater weakness and loss of motor skill ability seen in the older age

  15. Social distance influences the outcome evaluation of cooperation and conflict: Evidence from event-related potentials.

    Science.gov (United States)

    Chen, Yezi; Lu, Jiamei; Wang, Yiwen; Feng, Zhouqi; Yuan, Bo

    2017-04-24

    Previous research shows that social distance plays an important role in promoting cooperation and that subtle cues that reduce social distance increase the tendency to cooperate. However, it is unclear how social distance influences our outcome evaluation of cooperative and conflict feedback. The present study investigated the influence of social distance on cooperative and conflict behavior and the evaluation process of the cooperative and conflict outcomes, using the event-related potentials (ERPs) technique. We recorded ERPs from 14 normal adults playing a social game task against a friend and a stranger. The results showed that the FRN (Feedback Related Negativity) and P300 were affected by the opponent's choice to cooperate or aggress; however, only the P300 was affected by social distance. Specifically, when the opponent chose to cooperate, the feedback elicited a smaller FRN and a larger P300 amplitude; and compared with playing against friends, the P300 had a larger amplitude when participants gaming with strangers. Our results indicate that at the early stage of the evaluation of cooperation and conflict outcomes, individuals may initially and quickly encode the valence of outcomes, judging whether an outcome is consistent with their expectations. However, at the late stage, which involves a top-down cognitive appraisal process, some social factors, such as social distance, may moderate processing of attention resource allocation of feedback about outcomes, and of higher-level motivation/affective appraisal. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Influence of field strength, coil type and image resolution on assessment of synovitis by unenhanced MRI - a comparison with contrast-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Eshed, Iris [The Sheba Medical Center, Department of Diagnostic Imaging, Tel Hashomer (Israel); Tel Aviv University, Sackler School of Medicine, Tel Aviv (Israel); Krabbe, Simon; Axelsen, Mette; Pedersen, Susanne Juhl [Copenhagen University Hospital Glostrup, Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Copenhagen (Denmark); Oestergaard, Mikkel [Copenhagen University Hospital Glostrup, Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Copenhagen (Denmark); Copenhagen University Hospital Gentofte, Department of Rheumatology/C, Copenhagen (Denmark); Boeyesen, Pernille [Diakonhjemmet Hospital, Department of Rheumatology, Oslo (Norway); Moeller, Jakob M. [Copenhagen University Hospital at Herlev, Department of Radiology, Copenhagen (Denmark); Therkildsen, Flemming [Metropolitan University College, Copenhagen (Denmark); Madsen, Ole Rintek [Copenhagen University Hospital Gentofte, Department of Rheumatology/C, Copenhagen (Denmark)

    2015-04-01

    To explore if the reliability of synovitis assessment by unenhanced MRI is influenced by different MRI field-strengths, coil types and image resolutions in RA patients. Forty-one RA patients and 12 healthy controls underwent hand MRI (wrist and 2{sup nd}-5{sup th} metacarpophalangeal joints) at 4 different field-strengths (0.23 T/0.6 T/1.5 T/3.0 T) on the same day. Seven protocols using a STIR sequence with different field-strengths, coils (flex coils/dedicated phased-array extremity coils) and resolution were applied and scored blindly for synovitis (OMERACT-RAMRIS method). A 1.5 T post-contrast T1-weighted sequence was used as gold standard reference. Fair-good agreement (ICC=0.38-0.72) between the standard reference and the different STIR protocols (best agreement with extremity coil and small voxel size at 1.5 T). The accuracy for presence/absence of synovitis was very high per person (0.80-1.0), and moderate-high per joint (0.63-0.85), whereas exact agreements on scores were moderate (0.50-0.66). The intrareader agreement (15 patients and 3 controls) on presence/absence of synovitis was very high (0.87-1.0). Unenhanced MRI using STIR sequence is only moderately reliable for assessing hand synovitis in RA, when contrast-enhanced MRI is considered the gold standard reference. Contrast injection, field strength and coil type influence synovitis assessment, and should be considered before performing MRI in clinical trials and practice. (orig.)

  17. Factors that influence outcomes in cochlear implantation in adults, based on patient related characteristics - a retrospective study

    NARCIS (Netherlands)

    Kraaijenga, Véronique J C; Smit, Adriana L; Stegeman, Inge; Smilde, Jeanet J M; van Zanten, G A; Grolman, Wilko

    2016-01-01

    OBJECTIVE: Outcomes in speech perception following cochlear implantation in adults vary widely. Many studies have been carried out to identify and quantify factors that influence outcomes. This paper adds a new dimension to pre-existing literature. DESIGN: Single center retrospective cohort study.

  18. Influence of Pre-etching Times on Fatigue Strength of Self-etch Adhesives to Enamel.

    Science.gov (United States)

    Takamizawa, Toshiki; Barkmeier, Wayne W; Tsujimoto, Akimasa; Endo, Hajime; Tsuchiya, Kenji; Erickson, Robert L; Latta, Mark A; Miyazaki, Masashi

    To use shear bond strength (SBS) and shear fatigue strength (SFS) testing to determine the influence of phosphoric acid pre-etching times prior to application of self-etch adhesives on enamel bonding. Two single-step self-etch universal adhesives (Prime&Bond Elect and Scotchbond Universal), a conventional single-step self-etch adhesive (G-ӕnial Bond), and a conventional two-step self-etch adhesive (OptiBond XTR) were used. The SBS and SFS were obtained with phosphoric acid pre-etching for 3, 10, or 15 s prior to application of the adhesives, and without pre-etching (0 s) as a control. A staircase method was used to determine the SFS with 10 Hz frequency for 50,000 cycles or until failure occurred. The mean demineralization depth for each treated enamel surface was also measured using a profilometer. For all the adhesives, the groups with pre-etching showed significantly higher SBS and SFS than groups without pre-etching. However, there was no significant difference in SBS and SFS among groups with > 3 s of preetching. In addition, although the groups with pre-etching showed significantly deeper demineralization depths than groups without pre-etching, there was no significant difference in depth among groups with > 3 s of pre-etching. Three seconds of phosphoric acid pre-etching prior to application of self-etch adhesive can enhance enamel bonding effectiveness.

  19. Significant influence of the primary liver disease on the outcomes of hepatic retransplantation.

    LENUS (Irish Health Repository)

    Qasim, A

    2012-02-01

    BACKGROUND: There are many indications for hepatic retransplantation. AIM: To identify factors influencing retransplantation needs and outcomes. PATIENTS AND METHODS: Retransplantation records from January 1993 to March 2005 were analysed. Patient and disease characteristics and survival outcomes for retransplantation were compared between various groups. RESULTS: Totally, 286 primary and 42 hepatic retransplantations were performed. Retransplantation indications included primary sclerosing cholangitis (PSC), primary biliary cirrhosis, chronic hepatitis C (HCV), chronic active hepatitis (CAH), and alcohol-related disease. Mean follow-up post-retransplantation was 31 +\\/- 9 months. Actuarial patient survival at 3 months, 1 year, 3 years, 5 years, and at the end of study was 71.4, 69, 59.5, 54.7, and 50%, respectively. Early and late retransplantation had 1-year survival of 73 and 68.5%, respectively. Retransplantation need was significantly higher for PSC, HCV, and CAH. CONCLUSIONS: Hepatic retransplantation remains a successful salvage option for transplant complications; however, its need is significantly influenced by the primary liver disease.

  20. Effect of resistance training on muscle strength and rate of force development in healthy older adults: A systematic review and meta-analysis.

    Science.gov (United States)

    Guizelini, Pedrode Camargo; de Aguiar, Rafael Alves; Denadai, Benedito Sérgio; Caputo, Fabrizio; Greco, Camila Coelho

    2018-02-01

    Rapid force capacity, identified by rate of rise in contractile force at the onset of contraction, i.e., the rate of force development (RFD), has been considered an important neuromuscular parameter of physical fitness in elderly individuals. Randomized control studies conducted in adults have found that resistance training may elicit different outcomes in terms of RFD and muscle strength. Thus, the main purpose of this study was to review systematically the literature for studies regarding the influence of resistance training on muscle strength and RFD in elderly persons. A literature search was performed in major electronic databases from inception to March 2017. Studies including health individuals with a mean age≥60years, describing the effect of resistance training on RFD and muscle strength were found eligible. The outcomes were calculated as the difference in percentage change between control and experimental groups (% change) and data were presented as mean±95% confidence limits. Meta-analyses were performed using a random-effects model and, in addition, simple and multiple meta-regression analyses were used to identify effects of age, training type, sessions per week and training duration on % change in RFD and muscle strength. Thirteen training effects were collected from 10 studies included in the meta-analysis. The resistance training program had a moderate beneficial effect on both muscle strength (% change=18.40%, 95% CL 13.69-23.30, pchange=26.68, 95% CL 14.41-35.52, pchanges in muscle strength and RFD. It can be concluded that explosive training and heavy strength training are effective resistance training methods aiming to improve both muscle strength and RFD after short-to-medium training period. However, muscle strength and RFD seem to adapt differently to resistance training programs, suggesting caution for their interchangeable use in clinical assessments of the elderly. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Influence of method and period of storage on the microtensile bond strength of indirect composite resin restorations to dentine

    Directory of Open Access Journals (Sweden)

    Fernanda Ribeiro Santana

    2008-12-01

    Full Text Available This study evaluated the influence of the method and period of storage on the adhesive bond strength of indirect composite resin to bovine dentin. Ninety bovine incisors were stored in three different solutions: 0.2% thymol, 10% formalin, and 0.2% sodium azide, during 3 periods of storage: 7 days, 30 days and 6 months, resulting in 9 groups (n = 10. The roots were cut off and the buccal surface was ground with #600-grit silicon carbide paper. The surface was conditioned with 37% phosphoric acid for 15 s and a composite resin restoration (TPH Spectrum was fixed using a one-bottle adhesive system (Adper Single Bond and a dual-cured resinous cement (Rely X ARC under a load of 500 g for 5 minutes. The samples were serially cut perpendicular to the bonded interface to obtain slices of 1.2 mm in thickness. Each slab was trimmed with a cylindrical diamond bur resulting in an hourglass shape with a cross-sectional area of approximately 1 mm². The microtensile bond strength (μTBS testing was performed in a testing machine (EMIC 2000 DL at a 0.5 mm/minute crosshead-speed until failure. After fracture, the specimens were examined under SEM to analyze the mode of fracture. μTBS Means were expressed in MPa and the data were analyzed by two-way ANOVA (3X3 and the Tukey test (α = 0.05. The storage times of 7 and 30 days produced no significant difference irrespective of the solution type. The formalin and thymol solutions, however, did have a negative influence on bond strength when the teeth were stored for 6 months.

  2. 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.

  3. The Influence of Investment in Workplace Learning on Learning Outcomes and Organizational Performance

    Science.gov (United States)

    Park, Yoonhee; Jacobs, Ronald L.

    2011-01-01

    Although the importance of workplace learning has been recognized in research and practice, there is little empirical support that describes how workplace learning, including both formal and informal learning, is linked to organizational performance. This study investigated the influence of investment in workplace learning on learning outcomes and…

  4. Influence of sodalite zeolite infiltration on the coefficient of thermal expansion and bond strength of all-ceramic dental prostheses.

    Science.gov (United States)

    Naji, Ghassan Abdul-Hamid; Omar, Ros Anita; Yahya, Rosiyah

    2017-03-01

    In all-ceramic systems, a high incidence of veneer chip-off has been reported in clinical studies. Coefficient of thermal expansion (CTE) behaviour is one of the factors that may increase residual stress in the interface and influence the veneer/core bond strength. Therefore, this study aimed to evaluate the effect of sodalite zeolite-infiltration on the CTE behaviour and bond strength of different all-ceramic prostheses. The case-study groups were synthesized sodalite zeolite-infiltrated alumina (IA-SOD) and synthesized sodalite zeolite-infiltrated zirconia-toughened alumina (ZTA) (IZ-SOD), while the control groups were glass-infiltrated alumina (IA-glass) and glass-infiltrated ZTA (IZ-glass). Forty cylindrical-shaped samples measuring 5 mm in diameter and 10 mm in height were tested for CTE using a thermo-mechanical analyser machine, and forty disc-shaped ceramic samples measuring 12 mm in diameter and 1.2 ± 0.2 mm in thickness were prepared using specially designed stainless steel split mould and veneered by cylinder-shaped (2 mm high × 2 mm diameter) low-fusing porcelain (Vita VM7). The veneer/core samples were sintered and tested for shear bond strength using a high precision universal testing machine. Scanning electron microscope, stereo microscope, atomic force microscope, and energy-dispersive X-ray spectroscopy were used to investigate the structural characteristics of samples at the fracture surface. The collected data were analyzed with a one-way ANOVA and Tukey HSD test (α=.05). IZ-SOD revealed highest CTE and shear bond strength values, while the IA-glass revealed the lowest values than the other groups. There was no significant difference in CTE and bond strength among IZ-SOD, IA-SOD and IZ-glass samples (p>0.05). The experimental SOD zeolite-infiltrated samples revealed higher CTE mismatch and bond strength along with a more favourable mode of failure than did the commercial glass-infiltrated samples. Sandblast technique is considered as effective

  5. Fracture Energy of High-Strength Concrete in Compression

    DEFF Research Database (Denmark)

    Dahl, Henrik; Brincker, Rune

    is essential for understanding the fracture mechanism of concrete in compression. In this paper a series of tests is reported, carried out for the purpose of studying the fracture mechanical properties of concrete in compression. Including the measurement and study of the descending branch, a new experimental...... method has been used to investigate the influence of boundary conditions, loading rate, size effects and the influence of the strength on the fracture energy of high-strength concrete over the range 70 MPa to 150 MPa, expressed in nominal values....

  6. Effect of Water on Coal Strength | Singh | Momona Ethiopian Journal ...

    African Journals Online (AJOL)

    Water content is one of the most important factors influencing the rock strength. The present study has been conducted to see how coal strength changes under dry and water saturated conditions. The study reveals that the strength of coal decreases with increasing moisture. For rock mechanics and rock engineering ...

  7. The sleeping patterns of Head Start children and the influence on developmental outcomes.

    Science.gov (United States)

    Schlieber, M; Han, J

    2018-05-01

    Sleep has a significant influence on children's development. The objective of this study was to investigate Head Start children's sleeping patterns and the impact on cognitive and behavioural outcomes. Using the 2009 cohort of the Head Start Family and Child Experiences Survey (N = 2,868), information on sleeping patterns was assessed through parent interviews. Cognitive outcomes were assessed using direct assessments (Peabody Picture Vocabulary Test-IV, the Expressive One-Word Picture Vocabulary Test, and Subtests of the Woodcock-Johnson III) in addition to teacher report. Behavioural outcomes were assessed through parent and teacher reports. A multiple regression analysis was performed for each outcome variable. Descriptive findings showed that 89% of children had a regular bedtime at least 4 days per week and that the average amount of sleep per night was 10.41 hr. White mothers were more likely than other racial groups to adhere to a consistent bedtime, and maternal employment predicted less hour of sleep per night. Multiple regression analyses revealed that disrupted sleep had a negative influence on cognitive outcomes, especially in areas of mathematical problem solving, receptive language, teacher-reported literacy behaviours, and approaches to learning. Disrupted sleep was associated with the risk of misbehaviour by increasing teacher and parent ratings on aggressive behaviours, hyperactivity, and withdrawing in addition to decreased scores on overall social skills. Having an inconsistent bedtime negatively predicted expressive vocabulary and teacher-reported literacy behaviours. The findings of this study support the influential role of sleep on children's development. Sleeping through the night and having a consistent bedtime were found to be predictive of many areas of cognitive and behavioural development. Head Start staff can provide the supports to increase parental knowledge on appropriate child sleep practices. © 2017 John Wiley & Sons Ltd.

  8. Influence of air-powder polishing on bond strength and surface-free energy of universal adhesive systems.

    Science.gov (United States)

    Tamura, Yukie; Takamizawa, Toshiki; Shimamura, Yutaka; Akiba, Shunsuke; Yabuki, Chiaki; Imai, Arisa; Tsujimoto, Akimasa; Kurokawa, Hiroyasu; Miyazaki, Masashi

    2017-11-29

    The influences of air-powder polishing with glycine or sodium bicarbonate powders on shear bond strengths (SBS) and surface-free energies of universal adhesives were examined. Scotchbond Universal Adhesive (SU, 3M ESPE), G-Premio Bond (GP, GC), Adhese Universal (AU, Ivoclar Vivadent), and All-Bond Universal (AB, Bisco) were used in this study. Bovine dentin surfaces were air polished with glycine or sodium bicarbonate powders prior to the bonding procedure, and resin pastes were bonded to the dentin surface using universal adhesives. SBSs were determined after 24-h storage in distilled water at 37°C. Surface-free energy was then determined by measuring contact angles using three test liquids on dentin surfaces. Significantly lower SBSs were observed for dentin that was air-powder polished and surface-free energies were concomitantly lowered. This study indicated that air-powder polishing influences SBSs and surface-free energies. However, glycine powder produced smaller changes in these surface parameters than sodium bicarbonate.

  9. Influence of pre-existing inflammation on the outcome of acute coronary syndrome

    DEFF Research Database (Denmark)

    Odeberg, J.; Freitag, M.; Forssell, Henrik

    2016-01-01

    Objectives: Inflammation is a well-established risk factor for the development of coronary artery disease (CAD) and acute coronary syndrome (ACS). However, less is known about its influence on the outcome of ACS. The aim of this study was to determine if blood biomarkers of inflammation were...... that a pre-existing low-grade inflammation may dispose towards MI over UA....

  10. Influence of muscle strength, physical activity and weight on bone mass in a population-based sample of 1004 elderly women.

    Science.gov (United States)

    Gerdhem, P; Ringsberg, K A M; Akesson, K; Obrant, K J

    2003-09-01

    High physical activity level has been associated with high bone mass and low fracture risk and is therefore recommended to reduce fractures in old age. The aim of this study was to estimate the effect of potentially modifiable variables, such as physical activity, muscle strength, muscle mass and weight, on bone mass in elderly women. The influence of isometric thigh muscle strength, self-estimated activity level, body composition and weight on bone mineral density (dual energy X-ray absorptiometry; DXA) in total body, hip and spine was investigated. Subjects were 1004 women, all 75 years old, taking part in the Malmö Osteoporosis Prospective Risk Assessment (OPRA) study. Physical activity and muscle strength accounted for 1-6% of the variability in bone mass, whereas weight, and its closely associated variables lean mass and fat mass, to a much greater extent explained the bone mass variability. We found current body weight to be the variable with the most substantial influence on the total variability in bone mass (15-32% depending on skeletal site) in a forward stepwise regression model. Our findings suggest that in elderly women, the major fracture-preventive effect of physical activity is unlikely to be mediated through increased bone mass. Retaining or even increasing body weight is likely to be beneficial to the skeleton, but an excess body weight increase may have negative effects on health. Nevertheless, training in elderly women may have advantages by improving balance, co-ordination and mobility and therefore decreasing the risk of fractures.

  11. Influence of different pre-etching times on fatigue strength of self-etch adhesives to dentin.

    Science.gov (United States)

    Takamizawa, Toshiki; Barkmeier, Wayne W; Tsujimoto, Akimasa; Suzuki, Takayuki; Scheidel, Donal D; Erickson, Robert L; Latta, Mark A; Miyazaki, Masashi

    2016-04-01

    The purpose of this study was to use shear bond strength (SBS) and shear fatigue strength (SFS) testing to determine the influence on dentin bonding of phosphoric acid pre-etching times before the application of self-etch adhesives. Two single-step self-etch universal adhesives [Prime & Bond Elect (EL) and Scotchbond Universal (SU)], a conventional single-step self-etch adhesive [G-aenial Bond (GB)], and a two-step self-etch adhesive [OptiBond XTR (OX)] were used. The SBS and SFS values were obtained with phosphoric acid pre-etching times of 3, 10, or 15 s before application of the adhesives, and for a control without pre-etching. For groups with 3 s of pre-etching, SU and EL showed higher SBS values than control groups. No significant difference was observed for GB among the 3 s, 10 s, and control groups, but the 15 s pre-etching group showed significantly lower SBS and SFS values than the control group. No significant difference was found for OX among the pre-etching groups. Reducing phosphoric acid pre-etching time can minimize the adverse effect on dentin bonding durability for the conventional self-etch adhesives. Furthermore, a short phosphoric acid pre-etching time enhances the dentin bonding performance of universal adhesives. © 2016 Eur J Oral Sci.

  12. Humidity effects on wire insulation breakdown strength.

    Energy Technology Data Exchange (ETDEWEB)

    Appelhans, Leah

    2013-08-01

    Methods for the testing of the dielectric breakdown strength of insulation on metal wires under variable humidity conditions were developed. Two methods, an ASTM method and the twisted pair method, were compared to determine if the twisted pair method could be used for determination of breakdown strength under variable humidity conditions. It was concluded that, although there were small differences in outcomes between the two testing methods, the non-standard method (twisted pair) would be appropriate to use for further testing of the effects of humidity on breakdown performance. The dielectric breakdown strength of 34G copper wire insulated with double layer Poly-Thermaleze/Polyamide-imide insulation was measured using the twisted pair method under a variety of relative humidity (RH) conditions and exposure times. Humidity at 50% RH and below was not found to affect the dielectric breakdown strength. At 80% RH the dielectric breakdown strength was significantly diminished. No effect for exposure time up to 140 hours was observed at 50 or 80%RH.

  13. Influence of cold deformation and annealing on hydrogen embrittlement of cold hardening bainitic steel for high strength bolts

    Energy Technology Data Exchange (ETDEWEB)

    Hui, Weijun, E-mail: wjhui@bjtu.edu.cn [School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Zhang, Yongjian; Zhao, Xiaoli; Shao, Chengwei [School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China); Wang, Kaizhong; Sun, Wei; Yu, Tongren [Technical Center, Maanshan Iron & Steel Co., Ltd., Maanshan 243002, Anhui (China)

    2016-04-26

    The influence of cold drawing and annealing on hydrogen embrittlement (HE) of newly developed cold hardening bainitic steel was investigated by using slow strain rate testing (SSRT) and thermal desorption spectrometry (TDS), for ensuring safety performance of 10.9 class high strength bolts made of this kind of steel against HE under service environments. Hydrogen was introduced into the specimen by electrochemical charging. TDS analysis shows that the hydrogen-charged cold drawn specimen exhibits an additional low-temperature hydrogen desorption peak besides the original high-temperature desorption peak of the as-rolled specimen, causing remarkable increase of absorbed hydrogen content. It is found that cold drawing significantly enhances the susceptibility to HE, which is mainly attributed to remarkable increase of diffusible hydrogen absorption, the occurrence of strain-induced martensite as well as the increase of strength level. Annealing after cold deformation is an effective way to improve HE resistance and this improvement strongly depends on annealing temperature, i.e. HE susceptibility decreases slightly with increasing annealing temperature up to 200 °C and then decreases significantly with further increasing annealing temperature. This phenomenon is explained by the release of hydrogen, the recovery of cold worked microstructure and the decrease of strength with increasing annealing temperature.

  14. The application of the VIA Classification of Strengths to youth with and without disabilities

    NARCIS (Netherlands)

    Shogren, Karrie A.; Wehmeyer, Michael L.; Lang, K.M.; Niemiec, R.M.; Seo, Hyojeong

    2017-01-01

    Considering strengths when planning for postschool outcomes is critically important for all youth, including youth with disabilities, as strengths should guide the identification of meaningful postschool goals. However, there are a limited number of strengths-based assessment tools that have been

  15. Influences of Fascicle Length During Isometric Training on Improvement of Muscle Strength.

    Science.gov (United States)

    Tanaka, Hiroki; Ikezoe, Tome; Umehara, Jun; Nakamura, Masatoshi; Umegaki, Hiroki; Kobayashi, Takuya; Nishishita, Satoru; Fujita, Kosuke; Araki, Kojiro; Ichihashi, Noriaki

    2016-11-01

    Tanaka, H, Ikezoe, T, Umehara, J, Nakamura, M, Umegaki, H, Kobayashi, T, Nishishita, S, Fujita, K, Araki, K, and Ichihashi, N. Influences of fascicle length during isometric training on improvement of muscle strength. J Strength Cond Res 30(11): 3249-3255, 2016-This study investigated whether low-intensity isometric training would elicit a greater improvement in maximum voluntary contraction (MVC) at the same fascicle length, rather than the joint angle, adopted during training. Sixteen healthy women (21.8 ± 1.5 years) were randomly divided into an intervention group and a control group. Before (Pre) and after (Post) training, isometric plantarflexion MVCs were measured every 10° through the range of ankle joint position from 20° dorsiflexion to 30° plantarflexion (i.e., 6 ankle angles). Medial gastrocnemius fascicle length was also measured at each position, using B-mode ultrasound under 3 conditions of muscle activation: at rest, 30%MVC at respective angles, and MVC. Plantarflexion resistance training at an angle of 20° plantarflexion was performed 3 days a week for 4 weeks at 30%MVC using 3 sets of twenty 3-second isometric contractions. Maximum voluntary contraction in the intervention group increased at 0 and 10° plantarflexion (0°; Pre: 81.2 ± 26.5 N·m, Post: 105.0 ± 21.6 N·m, 10°; Pre: 63.0 ± 23.6 N·m, Post: 81.3 ± 20.3 N·m), which was not the angle used in training (20°). However, the fascicle length adopted in training at 20° plantarflexion and 30%MVC was similar to the value at 0 or 10° plantarflexion at MVC. Low-intensity isometric training at a shortened muscle length may be effective for improving MVC at a lengthened muscle length because of specificity of the fascicle length than the joint angle.

  16. Effect of silicon solar cell processing parameters and crystallinity on mechanical strength

    Energy Technology Data Exchange (ETDEWEB)

    Popovich, V.A.; Yunus, A.; Janssen, M.; Richardson, I.M. [Delft University of Technology, Department of Materials Science and Engineering, Delft (Netherlands); Bennett, I.J. [Energy Research Centre of the Netherlands, Solar Energy, PV Module Technology, Petten (Netherlands)

    2011-01-15

    Silicon wafer thickness reduction without increasing the wafer strength leads to a high breakage rate during subsequent handling and processing steps. Cracking of solar cells has become one of the major sources of solar module failure and rejection. Hence, it is important to evaluate the mechanical strength of solar cells and influencing factors. The purpose of this work is to understand the fracture behavior of silicon solar cells and to provide information regarding the bending strength of the cells. Triple junctions, grain size and grain boundaries are considered to investigate the effect of crystallinity features on silicon wafer strength. Significant changes in fracture strength are found as a result of metallization morphology and crystallinity of silicon solar cells. It is observed that aluminum paste type influences the strength of the solar cells. (author)

  17. Mind-muscle connection training principle: influence of muscle strength and training experience during a pushing movement.

    Science.gov (United States)

    Calatayud, Joaquin; Vinstrup, Jonas; Jakobsen, Markus D; Sundstrup, Emil; Colado, Juan Carlos; Andersen, Lars L

    2017-07-01

    To investigate the effect of different attentional focus conditions on muscle activity during the push-up exercise and to assess the possible influence of muscle strength and training experience. Eighteen resistance-trained men performed 1RM bench press testing and were familiarized with the procedure during the first session. In the second session, three different conditions were randomly performed: regular push-up and push-up focusing on using the pectoralis major and triceps brachii muscles, respectively. Surface electromyography (EMG) was recorded and analyzed (EMG normalized to max; nEMG) for the triceps brachii and pectoralis major muscles. Participants had on average 8 (SD 6) years of training experience and 1RM of 1.25 (SD 0.28) kg per kg bodyweight. Focusing on using pectoralis major increased activity in this muscle by 9% nEMG (95% CI 5-13; Cohen's d 0.60) compared with the regular condition. Triceps activity was not significantly influenced by triceps focus although borderline significant, with a mean difference of 5% nEMG (95% CI 0-10; Cohen's d 0.30). However, years of training experience was positively associated with the ability to selectively activate the triceps (β = 0.41, P = 0.04), but not the pectoralis. Bench press 1RM was not significantly associated with the ability to selectively activate the muscles. Pectoralis activity can be increased when focusing on using this muscle during push-ups, whereas the ability to do this for the triceps is dependent on years of training experience. Maximal muscle strength does not appear to be a decisive factor for the ability to selectively activate these muscles.

  18. 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.

  19. The added value of measuring thumb and finger strength when comparing strength measurements in hypoplastic thumb patients.

    Science.gov (United States)

    Molenaar, H M Ties; Selles, Ruud W; de Kraker, Marjolein; Stam, Henk J; Hovius, Steven E R

    2013-10-01

    When interventions to the hand are aimed at improving function of specific fingers or the thumb, the RIHM (Rotterdam Intrinsic Hand Myometer) is a validated tool and offers more detailed information to assess strength of the involved joints besides grip and pinch measurements. In this study, strength was measured in 65 thumbs in 40 patients diagnosed with thumb hypoplasia. These 65 thumbs were classified according to Blauth. Longitudinal radial deficiencies were also classified. The strength measurements comprised of grip, tip, tripod and key pinch. Furthermore palmar abduction and opposition of the thumb as well as abduction of the index and little finger were measured with the RIHM. For all longitudinal radial deficiency patients, grip and pinch strength as well as palmar abduction and thumb opposition were significantly lower than reference values (P<0.001). However, strength in the index finger abduction and the little finger abduction was maintained or decreased to a lesser extent according to the degree of longitudinal radial deficiency. All strength values decreased with increasing Blauth-type. Blauth-type II hands (n=15) with flexor digitorum superficialis 4 opposition transfer including stabilization of the metacarpophalangeal joint showed a trend toward a higher opposition strength without reaching statistical significance (P=0.094),however compared to non-operated Blauth-type II hands (n=6) they showed a lower grip strength (P=0.019). The RIHM is comparable in accuracy to other strength dynamometers. Using the RIHM, we were able to illustrate strength patterns on finger-specific level, showing added value when evaluating outcome in patients with hand related problems. © 2013.

  20. Strengths, weaknesses, opportunities and threats

    DEFF Research Database (Denmark)

    Bull, Joseph William; Jobstvogt, N.; Böhnke-Henrichs, A.

    2016-01-01

    The ecosystem services concept (ES) is becoming a cornerstone of contemporary sustainability thought. Challenges with this concept and its applications are well documented, but have not yet been systematically assessed alongside strengths and external factors that influence uptake. Such an assess...

  1. Strengths, Weaknesses, Opportunities and Threats

    NARCIS (Netherlands)

    Bull, J.W.; Jobstvogt, N.; Böhnke-Henrichs, A.; Mascarenhas, A.; Sitas, N.; Baulcomb, C.; Lambini, C.K.; Rawlins, M.; Baral, H.; Zähringer, J.; Carter-Silk, E.; Balzan, M.V.; Kenter, J.O.; Häyhä, T.; Petz, K.; Koss, R.

    2016-01-01

    The ecosystem services concept (ES) is becoming a cornerstone of contemporary sustainability thought. Challenges with this concept and its applications are well documented, but have not yet been systematically assessed alongside strengths and external factors that influence uptake. Such an

  2. Concordance of outcomes of pairs of kidneys transplanted into different recipients.

    LENUS (Irish Health Repository)

    Traynor, Carol

    2012-09-01

    Kidney transplant outcomes are influenced by donor characteristics, including age and gender. Additional donor factors, both genetic and environmental, also influence graft outcome. We aim to assess the strength of donor factors in determining kidney transplant outcomes by comparing paired kidneys from a single donor transplanted into different recipients. We conducted a retrospective cohort study of outcomes of pairs of deceased donor kidneys transplanted in our centre between 1992 and 2008. We examined the relationship within pairs for eGFR at 1 year and at 5 years post-transplant using Spearman\\'s Correlation and the concordance of pairs of transplant kidneys with respect to the occurrence of acute rejection and delayed graft function (DGF). A total of 652 recipient pairs were analysed. Spearman\\'s correlation for eGFR was 0.36 at 1 year and 0.36 at 5 years post-transplant. The incidence of DGF was 11%. The odds ratio of DGF occurring if the contralateral kidney had DGF was 5.99 (95% CI, 3.19-11.25). There is a significant degree of relationship within pairs of kidneys transplanted from the same donor for serum creatinine at 1 year and 5 years post-transplant and also for the occurrence of delayed graft function.

  3. Relation between the Disability of the Arm, Shoulder and Hand Score and Muscle Strength in Post-Cardiac Surgery Patients.

    Science.gov (United States)

    Izawa, Kazuhiro P; Kasahara, Yusuke; Hiraki, Koji; Hirano, Yasuyuki; Watanabe, Satoshi

    2017-11-27

    Background: The Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire is a valid and reliable patient-reported outcome measure. DASH can be assessed by self-reported upper extremity disability and symptoms. We aimed to examine the relationship between the physiological outcome of muscle strength and the DASH score after cardiac surgery. Methods: This cross-sectional study assessed 50 consecutive cardiac patients that were undergoing cardiac surgery. Physiological outcomes of handgrip strength and knee extensor muscle strength and the DASH score were measured at one month after cardiac surgery and were assessed. Results were analyzed using Spearman correlation coefficients. Results: The final analysis comprised 43 patients (men: 32, women: 11; age: 62.1 ± 9.1 years; body mass index: 22.1 ± 4.7 kg/m²; left ventricular ejection fraction: 53.5 ± 13.7%). Respective handgrip strength, knee extensor muscle strength, and DASH score were 27.4 ± 8.3 kgf, 1.6 ± 0.4 Nm/kg, and 13.3 ± 12.3, respectively. The DASH score correlated negatively with handgrip strength ( r = -0.38, p = 0.01) and with knee extensor muscle strength ( r = -0.32, p = 0.04). Conclusion: Physiological outcomes of both handgrip strength and knee extensor muscle strength correlated negatively with the DASH score. The DASH score appears to be a valuable tool with which to assess cardiac patients with poor physiological outcomes, particularly handgrip strength as a measure of upper extremity function, which is probably easier to follow over time than lower extremity function after patients complete cardiac rehabilitation.

  4. Relation between the Disability of the Arm, Shoulder and Hand Score and Muscle Strength in Post-Cardiac Surgery Patients

    Directory of Open Access Journals (Sweden)

    Kazuhiro P. Izawa

    2017-11-01

    Full Text Available Background: The Disabilities of the Arm, Shoulder, and Hand (DASH questionnaire is a valid and reliable patient-reported outcome measure. DASH can be assessed by self-reported upper extremity disability and symptoms. We aimed to examine the relationship between the physiological outcome of muscle strength and the DASH score after cardiac surgery. Methods: This cross-sectional study assessed 50 consecutive cardiac patients that were undergoing cardiac surgery. Physiological outcomes of handgrip strength and knee extensor muscle strength and the DASH score were measured at one month after cardiac surgery and were assessed. Results were analyzed using Spearman correlation coefficients. Results: The final analysis comprised 43 patients (men: 32, women: 11; age: 62.1 ± 9.1 years; body mass index: 22.1 ± 4.7 kg/m2; left ventricular ejection fraction: 53.5 ± 13.7%. Respective handgrip strength, knee extensor muscle strength, and DASH score were 27.4 ± 8.3 kgf, 1.6 ± 0.4 Nm/kg, and 13.3 ± 12.3, respectively. The DASH score correlated negatively with handgrip strength (r = −0.38, p = 0.01 and with knee extensor muscle strength (r = −0.32, p = 0.04. Conclusion: Physiological outcomes of both handgrip strength and knee extensor muscle strength correlated negatively with the DASH score. The DASH score appears to be a valuable tool with which to assess cardiac patients with poor physiological outcomes, particularly handgrip strength as a measure of upper extremity function, which is probably easier to follow over time than lower extremity function after patients complete cardiac rehabilitation.

  5. Influence of xylem ray integrity and degree of polymerization on bending strength of beech wood decayed by Pleurotus ostreatus and Trametes versicolor

    Science.gov (United States)

    Ehsan Bari; Reza Oladi; Olaf Schmidt; Carol A. Clausen; Katie Ohno; Darrel D. Nicholas; Mehrdad Ghodskhah Daryaei; Maryam Karim

    2015-01-01

    The scope of this research was to evaluate the influence of xylem ray (XR) and degree of polymerization (DP) of holocellulose in Oriental beech wood (Fagus orientalis Lipsky.) on impact bending strength against two white-rot fungi. Beech wood specimens, exposed to Pleurotus ostreatus and Trametes versicolor, were evaluated for...

  6. Strength and power of knee extensor muscles

    Directory of Open Access Journals (Sweden)

    Knežević Olivera

    2011-01-01

    Full Text Available In the studies of human neuromuscular function, the function of leg muscles has been most often measured, particularly the function of the knee extensors. Therefore, this review will be focused on knee extensors, methods for assessment of its function, the interdependence of strength and power, relations that describe these two abilities and the influence of various factors on their production (resistance training, stretching, movement tasks, age, etc.. Given that it consists of four separate muscles, the variability of their anatomical characteristics affects their participation in strength and power production, depending on the type of movement and motion that is performed. Since KE is active in a variety of activities it must be able to generate great strength in a large and diverse range of muscle lengths and high shortening velocities, in respect to different patterns of strength production, and thus different generation capacities within the muscle (Blazevich et al., 2006. It has been speculated that KE exerts its Pmax at workloads close to subject's own body weight or lower (Rahmani et al., 2001, which is very close to the maximum dynamic output hypothesis (MDI of Jaric and Markovic (2009. Changes under the influence of resistance training or biological age are variously manifested in muscle's morphological, physiological and neural characteristics, and thus in strength and power. Understanding the issues related to strength and power as abilities of great importance for daily activities, is also important for sports and rehabilitation. Performances improvement in sports in which leg muscles strength and power are crucial, as well as recovery after the injuries, are largely dependent on the research results regarding KE function. Also, the appropriate strength balance between knee flexors and extensors is important for the knee joint stability, so that the presence of imbalance between these two muscle groups might be a risk factor for

  7. Does the Rotator Cuff Tear Pattern Influence Clinical Outcomes After Surgical Repair?

    Science.gov (United States)

    Watson, Scott; Allen, Benjamin; Robbins, Chris; Bedi, Asheesh; Gagnier, Joel J; Miller, Bruce

    2018-03-01

    Limited literature exists regarding the influence of rotator cuff tear morphology on patient outcomes. To determine the effect of rotator cuff tear pattern (crescent, U-shape, L-shape) on patient-reported outcomes after rotator cuff repair. Cohort study; Level of evidence, 3. Patients undergoing arthroscopic repair of known full-thickness rotator cuff tears were observed prospectively at regular intervals from baseline to 1 year. The tear pattern was classified at the time of surgery as crescent, U-shaped, or L-shaped. Primary outcome measures were the Western Ontario Rotator Cuff Index (WORC), the American Shoulder and Elbow Surgeons (ASES), and a visual analog scale (VAS) for pain. The tear pattern was evaluated as the primary predictor while controlling for variables known to affect rotator cuff outcomes. Mixed-methods regression and analysis of variance (ANOVA) were used to examine the effects of tear morphology on patient-reported outcomes after surgical repair from baseline to 1 year. A total of 82 patients were included in the study (53 male, 29 female; mean age, 58 years [range, 41-75 years]). A crescent shape was the most common tear pattern (54%), followed by U-shaped (25%) and L-shaped tears (21%). There were no significant differences in outcome scores between the 3 groups at baseline. All 3 groups showed statistically significant improvement from baseline to 1 year, but analysis failed to show any predictive effect in the change in outcome scores from baseline to 1 year for the WORC, ASES, or VAS when tear pattern was the primary predictor. Further ANOVA also failed to show any significant difference in the change in outcome scores from baseline to 1 year for the WORC ( P = .96), ASES ( P = .71), or VAS ( P = .86). Rotator cuff tear pattern is not a predictor of functional outcomes after arthroscopic rotator cuff repair.

  8. Influence of cement compressive strength and porosity on augmentation performance in a model of orthopedic screw pull-out.

    Science.gov (United States)

    Pujari-Palmer, Michael; Robo, Celine; Persson, Cecilia; Procter, Philip; Engqvist, Håkan

    2018-01-01

    Disease and injuries that affect the skeletal system may require surgical intervention and internal fixation, i.e. orthopedic plate and screw insertion, to stabilize the injury and facilitate tissue repair. If the surrounding bone quality is poor the screws may migrate, or the bone may fail, resulting in fixation failure. While numerous studies have shown that cement augmentation of the interface between bone and implant can increase screw pull-out force, the physical properties of cement that influence pull-out force have not been investigated. The present study sought to determine how the physical properties of high strength calcium phosphate cements (hsCPCs, specifically dicalcium phosphate) affected the corresponding orthopedic screw pull-out force in urethane foam models of "healthy" and "osteoporotic" synthetic bone (Sawbones). In the simplest model, where only the bond strength between screw thread and cement (without Sawbone) was tested, the correlation between pull-out force and cement compressive strength (R 2 = 0.79) was weaker than correlation with total cement porosity (R 2 = 0.89). In open pore Sawbone that mimics "healthy" cancellous bone density the stronger cements produced higher pull-out force (50-60% increase). High strength, low porosity cements also produced higher pull-out forces (50-190% increase) in "healthy" Sawbones with cortical fixation if the failure strength of the cortical material was similar to, or greater than (a metal shell), actual cortical bone. This result is of particular clinical relevance where fixation with a metal plate implant is indicated, as the nearby metal can simulate a thicker cortical shell, thereby increasing the pull-out force of screws augmented with stronger cements. The improvement in pull-out force was apparent even at low augmentation volumes of 0.5mL (50% increase), which suggest that in clinical situations where augmentation volume is limited the stronger, lower porosity calcium phosphate cement (CPC) may

  9. The influence of individual, group, and relative self-esteem on outcome for patients undergoing group cognitive-behavioural therapy treatment.

    Science.gov (United States)

    Parker, Thomas J; Page, Andrew C; Hooke, Geoff R

    2013-11-01

    Despite a strong association between individual self-esteem and treatment outcome in group cognitive-behavioural therapy (GCBT), no study has investigated how patient outcomes might be influenced by an individual's self-esteem relative to other group members. The study comprised a retrospective examination of patients' data and used a multiple regression analysis to identify predictors of treatment outcome. Patients' pre-treatment self-esteem scores were assessed on a continuum and assigned to be low, medium, or high. Therapy groups were assigned to be either low, balanced or high self-esteem groups based on averaged self-esteem scores of participants. In this study, 3,878 patients who had completed a 10-day intensive cognitive behavioural group therapy programme at a private psychiatric facility were included in the study. The Rosenberg Self-Esteem measure was chosen to assess self-esteem. The three subscales of the Depression Anxiety Stress Scales were used as the outcome measures. Patient outcomes were influenced by pre-treatment self-esteem scores, such that higher initial self-esteem was associated with better treatment outcomes. Low group self-esteem was predictive of significantly better outcomes for depression, relative to higher self-esteem groups. Additionally, the combined influence of high individual self-esteem and low group self-esteem was associated with significantly enhanced depression improvement. High self-esteem patients perform better on outcome measures following completion of GCBT. Low self-esteem groups show greater improvement in depression symptoms. Similar results for depression are achieved when patients with high self-esteem complete treatment in low self-esteem groups. © 2013 The British Psychological Society.

  10. Modulating influences of memory strength and sensitivity of the retrieval test on the detectability of the sleep consolidation effect.

    Science.gov (United States)

    Schoch, Sarah F; Cordi, Maren J; Rasch, Björn

    2017-11-01

    Emotionality can increase recall probability of memories as emotional information is highly relevant for future adaptive behavior. It has been proposed that memory processes acting during sleep selectively promote the consolidation of emotional memories, so that neutral memories no longer profit from sleep consolidation after learning. This appears as a selective effect of sleep for emotional memories. However, other factors contribute to the appearance of a consolidation benefit and influence this interpretation. Here we show that the strength of the memory trace before sleep and the sensitivity of the retrieval test after sleep are critical factors contributing to the detection of the benefit of sleep on memory for emotional and neutral stimuli. 228 subjects learned emotional and neutral pictures and completed a free recall after a 12-h retention interval of either sleep or wakefulness. We manipulated memory strength by including an immediate retrieval test before the retention interval in half of the participants. In addition, we varied the sensitivity of the retrieval test by including an interference learning task before retrieval testing in half of the participants. We show that a "selective" benefit of sleep for emotional memories only occurs in the condition with high memory strength. Furthermore, this "selective" benefit disappeared when we controlled for the memory strength before the retention interval and used a highly sensitive retrieval test. Our results indicate that although sleep benefits are more robust for emotional memories, neutral memories similarly profit from sleep after learning when more sensitive indicators are used. We conclude that whether sleep benefits on memory appear depends on several factors, including emotion, memory strength and sensitivity of the retrieval test. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Effects of asymptomatic rotator cuff pathology on in vivo shoulder motion and clinical outcomes.

    Science.gov (United States)

    Baumer, Timothy G; Dischler, Jack; Mende, Veronica; Zauel, Roger; van Holsbeeck, Marnix; Siegal, Daniel S; Divine, George; Moutzouros, Vasilios; Bey, Michael J

    2017-06-01

    The incidence of asymptomatic rotator cuff tears has been reported to range from 15% to 39%, but the influence of asymptomatic rotator cuff pathology on shoulder function is not well understood. This study assessed the effects of asymptomatic rotator cuff pathology on shoulder kinematics, strength, and patient-reported outcomes. A clinical ultrasound examination was performed in 46 asymptomatic volunteers (age: 60.3 ± 7.5 years) with normal shoulder function to document the condition of their rotator cuff. The ultrasound imaging identified the participants as healthy (n = 14) or pathologic (n = 32). Shoulder motion was measured with a biplane x-ray imaging system, strength was assessed with a Biodex (Biodex Medical Systems, Inc., Shirley, NY, USA), and patient-reported outcomes were assessed using the Western Ontario Rotator Cuff Index and visual analog scale pain scores. Compared with healthy volunteers, those with rotator cuff pathology had significantly less abduction (P = .050) and elevation (P = .041) strength, their humerus was positioned more inferiorly on the glenoid (P = .018), and the glenohumeral contact path length was longer (P = .007). No significant differences were detected in the Western Ontario Rotator Cuff Index, visual analog scale, range of motion, or acromiohumeral distance. The differences observed between the healthy volunteers and those with asymptomatic rotator cuff pathology lend insight into the changes in joint mechanics, shoulder strength, and conventional clinical outcomes associated with the early stages of rotator cuff pathology. Furthermore, these findings suggest a plausible mechanical progression of kinematic and strength changes associated with the development of rotator cuff pathology. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  12. Influences of Gd on the microstructure and strength of Mg-4.5Zn alloy

    International Nuclear Information System (INIS)

    Yang Jie; Xiao Wenlong; Wang Lidong; Wu Yaoming; Wang Limin; Zhang Hongjie

    2008-01-01

    Microstructure and mechanical properties of peak-aged Mg-4.5Zn-xGd (x 0, 0.5, 1.0 and 1.5 wt.%) alloys have been investigated. The results showed that the grain size of the alloys was refined gradually with increasing Gd. Mg 5 Gd and Mg 3 Gd 2 Zn 3 phases were found in the Gd-containing alloys. The strengths were greatly improved with Gd additions, and the highest strength level was obtained in the Mg-4.5Zn-1.5Gd alloy, in which the ultimate tensile strength and yield strength were 231 MPa and 113 MPa, respectively. Through comparing with the Mg-4.5Zn alloy, the increments of ultimate tensile strength and yield strength were 22 MPa and 56 MPa, respectively. The improved strength was mainly correlated to the grain refining effect, the strengthening effect of the Mg 5 Gd and Mg 3 Gd 2 Zn 3 phases and also the hardening effect of the solutioned Gd atoms

  13. On the Influence of Nb/Ti Ratio on Environmentally-Assisted Crack Growth in High-Strength Nickel-Based Superalloys

    Science.gov (United States)

    Németh, A. A. N.; Crudden, D. J.; Collins, D. M.; Kuksenko, V.; Liebscher, C. H.; Armstrong, D. E. J.; Wilkinson, A. J.; Reed, R. C.

    2018-05-01

    The effect of Nb/Ti ratio on environmentally-assisted crack growth of three prototype Ni-based superalloys is studied. For these alloys, the yield strength is unaltered with increasing Nb/Ti ratio due to an increase in grain size. This situation has allowed the rationalization of the factors influencing damage tolerance at 700 °C. Primary intergranular cracks have been investigated using energy-dispersive X-ray spectroscopy in a scanning transmission electron microscope and the analysis of electron back-scatter diffraction patterns. Any possible detrimental effect of Nb on the observed crack tip damage due to Nb-rich oxide formation is not observed. Instead, evidence is presented to indicate that the tertiary γ'-precipitates are dissolving ahead of the crack consistent with the formation of oxides such as alumina and rutile. Our results have implications for alloy design efforts; at any given strength level, both more and less damage-tolerant variants of these alloys can be designed.

  14. Influence of spinal sagittal alignment, body balance, muscle strength, and physical ability on falling of middle-aged and elderly males.

    Science.gov (United States)

    Imagama, Shiro; Ito, Zenya; Wakao, Norimitsu; Seki, Taisuke; Hirano, Kenichi; Muramoto, Akio; Sakai, Yoshihito; Matsuyama, Yukihiro; Hamajima, Nobuyuki; Ishiguro, Naoki; Hasegawa, Yukiharu

    2013-06-01

    Risk factors for falling in elderly people remain uncertain, and the effects of spinal factors and physical ability on body balance and falling have not been examined. The objective of this study was to investigate how factors such as spinal sagittal alignment, spinal range of motion, body balance, muscle strength, and gait speed influence falling in the prospective cohort study. The subjects were 100 males who underwent a basic health checkup. Balance, SpinalMouse(®) data, grip strength, back muscle strength, 10-m gait time, lumbar lateral standing radiographs, body mass index, and fall history over the previous year were examined. Platform measurements of balance included the distance of movement of the center of pressure (COP) per second (LNG/TIME), the envelopment area traced by movement of the COP (E AREA), and the LNG/E AREA ratio. The thoracic/lumbar angle ratio (T/L ratio) and sagittal vertical axis (SVA) were used as an index of sagittal balance. LNG/TIME and E AREA showed significant positive correlations with age, T/L ratio, SVA, and 10-m gait time; and significant negative correlations with lumbar lordosis angle, sacral inclination angle, grip strength and back muscle strength. Multiple regression analysis showed significant differences for LNG/TIME and E AREA with T/L ratio, SVA, lumbar lordosis angle and sacral inclination angle (R (2) = 0.399). Twelve subjects (12 %) had experienced a fall over the past year. Age, T/L ratio, SVA, lumbar lordosis angle, sacral inclination angle, grip strength, back muscle strength, 10-m gait time, height of the intervertebral disc, osteophyte formation in radiographs and LNG/E AREA differed significantly between fallers and non-fallers. The group with SVA > 40 mm (n = 18) had a significant higher number of subjects with a single fall (6 single fallers/18: p = 0.0075) and with multiple falls (4 multiple fallers/18: p = 0.0095). Good spinal sagittal alignment, muscle strength and 10-m gait speed improve body balance

  15. Waiting Time for Coronal Preparation and the Influence of Different Cements on Tensile Strength of Metal Posts

    Directory of Open Access Journals (Sweden)

    Ilione Kruschewsky Costa Sousa Oliveira

    2012-01-01

    Full Text Available This study aimed to assess the effect of post-cementation waiting time for core preparation of cemented cast posts and cores had on retention in the root canal, using two different luting materials. Sixty extracted human canines were sectioned 16 mm from the root apex. After cast nickel-chromium metal posts and cores were fabricated and luted with zinc phosphate (ZP cement or resin cement (RC, the specimens were divided into 3 groups (n = 10 according to the waiting time for core preparation: no preparation (control, 15 minutes, or 1 week after the core cementation. At the appropriate time, the specimens were subjected to a tensile load test (0.5 mm/min until failure. Two-way ANOVA (time versus cement and the Tukey tests (P < 0.05 showed significantly higher (P < 0.05 tensile strength values for the ZP cement groups than for the RC groups. Core preparation and post-cementation waiting time for core recontouring did not influence the retention strength. ZP was the best material for intraradicular metal post cementation.

  16. Effects of High Intensity Interval Training and Strength Training on Metabolic, Cardiovascular and Hormonal Outcomes in Women with Polycystic Ovary Syndrome: A Pilot Study.

    Directory of Open Access Journals (Sweden)

    Ida Almenning

    Full Text Available Polycystic ovary syndrome is a common endocrinopathy in reproductive-age women, and associates with insulin resistance. Exercise is advocated in this disorder, but little knowledge exists on the optimal exercise regimes. We assessed the effects of high intensity interval training and strength training on metabolic, cardiovascular, and hormonal outcomes in women with polycystic ovary syndrome.Three-arm parallel randomized controlled trial. Thirty-one women with polycystic ovary syndrome (age 27.2 ± 5.5 years; body mass index 26.7 ± 6.0 kg/m2 were randomly assigned to high intensity interval training, strength training, or a control group. The exercise groups exercised three times weekly for 10 weeks.The main outcome measure was change in homeostatic assessment of insulin resistance (HOMA-IR. HOMA-IR improved significantly only after high intensity interval training, by -0.83 (95% confidence interval [CI], -1.45, -0.20, equal to 17%, with between-group difference (p = 0.014. After high intensity interval training, high-density lipoprotein cholesterol increased by 0.2 (95% CI, 0.02, 0.5 mmol/L, with between group difference (p = 0.04. Endothelial function, measured as flow-mediated dilatation of the brachial artery, increased significantly after high intensity interval training, by 2.0 (95% CI, 0.1, 4.0 %, between-group difference (p = 0.08. Fat percentage decreased significantly after both exercise regimes, without changes in body weight. After strength training, anti-Müllarian hormone was significantly reduced, by -14.8 (95% CI, -21.2, -8.4 pmol/L, between-group difference (p = 0.04. There were no significant changes in high-sensitivity C-reactive protein, adiponectin or leptin in any group.High intensity interval training for ten weeks improved insulin resistance, without weight loss, in women with polycystic ovary syndrome. Body composition improved significantly after both strength training and high intensity interval training. This pilot

  17. Effects of High Intensity Interval Training and Strength Training on Metabolic, Cardiovascular and Hormonal Outcomes in Women with Polycystic Ovary Syndrome: A Pilot Study.

    Science.gov (United States)

    Almenning, Ida; Rieber-Mohn, Astrid; Lundgren, Kari Margrethe; Shetelig Løvvik, Tone; Garnæs, Kirsti Krohn; Moholdt, Trine

    2015-01-01

    Polycystic ovary syndrome is a common endocrinopathy in reproductive-age women, and associates with insulin resistance. Exercise is advocated in this disorder, but little knowledge exists on the optimal exercise regimes. We assessed the effects of high intensity interval training and strength training on metabolic, cardiovascular, and hormonal outcomes in women with polycystic ovary syndrome. Three-arm parallel randomized controlled trial. Thirty-one women with polycystic ovary syndrome (age 27.2 ± 5.5 years; body mass index 26.7 ± 6.0 kg/m2) were randomly assigned to high intensity interval training, strength training, or a control group. The exercise groups exercised three times weekly for 10 weeks. The main outcome measure was change in homeostatic assessment of insulin resistance (HOMA-IR). HOMA-IR improved significantly only after high intensity interval training, by -0.83 (95% confidence interval [CI], -1.45, -0.20), equal to 17%, with between-group difference (p = 0.014). After high intensity interval training, high-density lipoprotein cholesterol increased by 0.2 (95% CI, 0.02, 0.5) mmol/L, with between group difference (p = 0.04). Endothelial function, measured as flow-mediated dilatation of the brachial artery, increased significantly after high intensity interval training, by 2.0 (95% CI, 0.1, 4.0) %, between-group difference (p = 0.08). Fat percentage decreased significantly after both exercise regimes, without changes in body weight. After strength training, anti-Müllarian hormone was significantly reduced, by -14.8 (95% CI, -21.2, -8.4) pmol/L, between-group difference (p = 0.04). There were no significant changes in high-sensitivity C-reactive protein, adiponectin or leptin in any group. High intensity interval training for ten weeks improved insulin resistance, without weight loss, in women with polycystic ovary syndrome. Body composition improved significantly after both strength training and high intensity interval training. This pilot study

  18. Leader Affect and Leadership Effectiveness: How leader affective displays influence follower outcomes

    OpenAIRE

    Visser, Victoria

    2013-01-01

    textabstractThe aim of this dissertation is to uncover the relationship between leader affective displays and leadership effectiveness. Five empirical studies were conducted to test the influence of several leader affective displays on different follower outcomes that indicate leadership effectiveness. The results showed that leader happy displays enhance followers’ creative performance, whereas leader sad displays enhance followers’ analytical performance. In addition, a leader displaying ha...

  19. Study Of Calcium And Potassium Different Nature Strength Gel Kappa-Carrageenan

    Directory of Open Access Journals (Sweden)

    Петро Васильович Гурський

    2015-07-01

    Full Text Available The influence of certain organic and mineral salts of potassium and calcium for strength gel kappa-carrageenan. The influence of the mass concentration of individual calcium for strength gels with different content kappa-carrageenan. Grounded mass concentration of some calcium salts for use in the composition of the jelly for sweet and savory dishes based on kappa-carrageenan

  20. The influence of age, sex, bulb position, visual feedback, and the order of testing on maximum anterior and posterior tongue strength and endurance in healthy belgian adults.

    Science.gov (United States)

    Vanderwegen, Jan; Guns, Cindy; Van Nuffelen, Gwen; Elen, Rik; De Bodt, Marc

    2013-06-01

    This study collected data on the maximum anterior and posterior tongue strength and endurance in 420 healthy Belgians across the adult life span to explore the influence of age, sex, bulb position, visual feedback, and order of testing. Measures were obtained using the Iowa Oral Performance Instrument (IOPI). Older participants (more than 70 years old) demonstrated significantly lower strength than younger persons at the anterior and the posterior tongue. Endurance remains stable throughout the major part of life. Gender influence remains significant but minor throughout life, with males showing higher pressures and longer endurance. The anterior part of the tongue has both higher strength and longer endurance than the posterior part. Mean maximum tongue pressures in this European population seem to be lower than American values and are closer to Asian results. The normative data can be used for objective assessment of tongue weakness and subsequent therapy planning of dysphagic patients.

  1. Influence of ultraviolet irradiation treatment on porcelain bond strength of titanium surfaces.

    Science.gov (United States)

    Kumasaka, Tomonari; Ohno, Akinori; Hori, Norio; Hoshi, Noriyuki; Maruo, Katsuichiro; Kuwabara, Atsushi; Seimiya, Kazuhide; Toyoda, Minoru; Kimoto, Katsuhiko

    2018-01-26

    To determine the effect of titanium (Ti) surface modification by ultraviolet irradiation (UVI) on the bond strength between Ti and porcelain. Grade 2 Ti plates were allotted to five groups: sandblasted (SA), 15 min UVI (UV), SA+5 min UVI (SA+UV5), SA+10 min UVI (SA+UV10), and SA+15 min UVI (SA+UV15). After surface treatment, porcelain was added. A precious metal (MC) was used for comparison with Ti. The effects of 24-h storage at room temperature versus thermal cycling only at 5 and 55°C in water were evaluated. Subsequently, the tensile strength of each sample was tested. Data were analyzed using one-way analysis of variance and the Tukey test. In both the room temperature and thermal cycling groups, the MC and SA+15 min UVI samples showed significantly greater bond strengths than the other samples (pbond strength between porcelain and the Ti surface.

  2. Market driving behaviour in organisations: Antecedents and outcomes

    Directory of Open Access Journals (Sweden)

    Jurie Van Vuuren

    2013-05-01

    Full Text Available Previous research suggests that the market driving behaviour of firms is linked to exceptional performance. However, the elements of market driving, its antecedents and outcomes, have so far not been empirically measured. The primary objectives of this study are to identify factors that describe market driving, develop a conceptual model, and then consider influencing factors and performance indicators drawn from the entrepreneurship and marketing literature. The model has been empirically tested using a sample of managers in the South African healthcare industry. A fully structured questionnaire was used to address the objective of this study. The realised sample of n=328 was used to analyse the conceptual model applying a partial least squares path modelling approach (PLS-PM. The results revealed that market driving is a firm behaviour and is distinguished by three distinct concepts: market sensing, influencing customer preferences and alliance formation. Three out of four antecedents: strategic orientation, entrepreneurial capital and entrepreneurial behaviour, influenced market driving ability positively. The study also demonstrated that market driving behaviour positively influences firm performance and relative competitive strength

  3. Influence of nanoparticles on color stability, microhardness, and flexural strength of acrylic resins specific for ocular prosthesis

    Directory of Open Access Journals (Sweden)

    Andreotti AM

    2014-12-01

    Full Text Available Agda Marobo Andreotti, Marcelo Coelho Goiato, Amália Moreno, Adhara Smith Nobrega, Aldiéris Alves Pesqueira, Daniela Micheline dos Santos Araçatuba Dental School, São Paulo State University, Araçatuba, São Paulo, Brazil Abstract: The aim of this study was to assess the effect of adding nanoparticles to N1 acrylic resin intended for artificial sclera, in terms of the color stability, microhardness, and flexural strength of the resin. Three hundred samples of N1 acrylic resin were used: 100 samples for color stability and microhardness tests (each test was performed on the opposite side of each sample, and 200 samples for flexural strength testing (100 samples before and after 1,008 hours of accelerated aging. Samples for each test were separated into ten groups (n=10, ie, without nanoparticles (control group or with nanoparticles of zinc oxide, titanium dioxide (TiO2, and barium sulfate at weight concentrations of 1%, 2%, and 2.5% (nanoparticle groups. Data were subjected to statistical analysis with nested analysis of variance and Tukey’s test (P<0.05 significance level. Among the nanoparticle groups, the TiO2 groups showed better color stability at all concentrations. Microhardness values increased after artificial aging, except for the control and zinc oxide groups. After aging, the 1%–2% TiO2 groups had significantly higher microhardness values compared with the other nanoparticle groups. Before aging, there was a significant difference in flexural strength between the control and nanoparticle groups. After aging, the control and TiO2 groups, regardless of concentration, showed the lowest flexural strength values. Incorporation of nanoparticles directly influenced the acrylic resin properties, with TiO2 being the most influential nanoparticle in terms of the evaluated properties. Keywords: acrylic resins, eye, artificial, color, hardness, nanoparticles

  4. Analysis of the influence of chemical treatment to the strength and surface roughness of FDM

    Science.gov (United States)

    Hambali, R. H.; Cheong, K. M.; Azizan, N.

    2017-06-01

    The applications of Additive Manufacturing (AM) technology have a greater functionality and wider range of application beyond an intention of prototyping. AM is the process of joining materials to form objects from Computer-Aided Design (CAD) models via layer upon layer process. One of AM technologies is the Fused Deposition Modelling (FDM), which use an extrusion method to create a part. FDM has been applied in many manufacturing applications includes an end-used parts. However, FDM tends to have bad surface quality due to staircase effect and post treatment is required. This chemical treatment is one of a way to improve the surface roughness of FDM fabricated parts. This method is one of economical and faster method. In order to enhance the surface finish of Acrylonitrile-Butadiene-Styrene (ABS) FDM parts by performing chemical treatment in an acetone solution as acetone has very low toxicity, high diffusion and low cost chemical solution. Therefore, the aim of this research is to investigate the influence of chemical treatment to the FDM used part in terms of surface roughness as well as the strength. In this project, ten specimens of standard ASTM D638 dogbone specimens have been fabricated using MOJO 3D printer. Five specimens from the dogbone were tested for surface roughness and tensile testing while another five were immersed in the chemical solution before the same testing. Based on results, the surface roughness of chemically treated dogbone has dramatically improved, compared to untreated dogbone with 97.2% of improvement. However, in term of strength, the tensile strength of dogbone is reduced 42.58% due to the rearrange of material properties and chemical effects to the joining of the filaments. In conclusion, chemical treatment is an economical and sustainable approach to enhance the surface quality of AM parts.

  5. Influence of dentinal regions on bond strengths of different adhesive systems.

    Science.gov (United States)

    Ozer, F; Unlü, N; Sengun, A

    2003-06-01

    This in vitro study assessed comparatively the shear bond strengths of three composite resins, 3M Valux Plus (3MVP), Herculite (H), Clearfil AP-X (CAP-X), a polyacid modified composite resin Dyract (D), and a resin modified glass-ionomer materials Vitremer (V), to cervical and buccal dentine regions of extracted human molar teeth. Four different bonding systems, 3M ScotchBond Multipurpose (SB), Clearfil Liner Bond 2 (LB2), Opti Bond (OB), and Prime & Bond 2.1 (PB 2.1) were used with the manufacturer's respective composite and compomer materials. One hundred freshly extracted mandibular molar teeth were selected for this study. Flat buccal dentine surfaces were created on 50 teeth and cylindrical rods of the five materials were bonded to the dentine surfaces. For assessment of cervical bond strengths, the materials were bonded to mesial and distal enamel bordered occlusal dentinal surfaces of the remaining 50 teeth. The five groups of restorative procedures were applied as follows; Group 1: SB + 3MVP, Group 2: LB2 + CAP-X, Group 3: OB + H, Group 4: PB2.1 + D, Group 5: Vitremer primer (VP) VP + V. Each restorative procedure thus had 20 specimens (10 buccal + 10 cervical). After 24 h of water storage (37 degrees C), the specimens were tested on a Universal Testing machine in shear with a cross head speed of 0.5 mm min-1. The bond strength values were calculated in MPa and the results were evaluated statistically using Kruskal-Wallis one-way/anova and Mann-Whitney U-tests. It was found that the bond strengths of SB + 3MVP, LB2 + CAP-X and VP + V to buccal dentine surfaces were significantly stronger (P 0.05). Vitremer was found the least successful adhesive material in terms of shear bond strength on both buccal and occluso-cervical dentine surfaces.

  6. Experimental knee joint pain during strength training and muscle strength gain in healthy subjects: a randomized controlled trial.

    Science.gov (United States)

    Sørensen, T J; Langberg, H; Hodges, P W; Bliddal, H; Henriksen, M

    2012-01-01

    Knee joint pain and reduced quadriceps strength are cardinal symptoms in many knee pathologies. In people with painful knee pathologies, quadriceps exercise reduces pain, improves physical function, and increases muscle strength. A general assumption is that pain compromises muscle function and thus may prevent effective rehabilitation. This study evaluated the effects of experimental knee joint pain during quadriceps strength training on muscle strength gain in healthy individuals. Twenty-seven healthy untrained volunteers participated in a randomized controlled trial of quadriceps strengthening (3 times per week for 8 weeks). Participants were randomized to perform resistance training either during pain induced by injections of painful hypertonic saline (pain group, n = 13) or during a nonpainful control condition with injection of isotonic saline (control group, n = 14) into the infrapatellar fat pad. The primary outcome measure was change in maximal isokinetic muscle strength in knee extension/flexion (60, 120, and 180 degrees/second). The group who exercised with pain had a significantly larger improvement in isokinetic muscle strength at all angular velocities of knee extension compared to the control group. In knee flexion there were improvements in isokinetic muscle strength in both groups with no between-group differences. Experimental knee joint pain improved the training-induced gain in muscle strength following 8 weeks of quadriceps training. It remains to be studied whether knee joint pain has a positive effect on strength gain in patients with knee pathology. Copyright © 2012 by the American College of Rheumatology.

  7. The influence of ceramic surface treatments on the micro-shear bond strength of composite resin to IPS Empress 2.

    Science.gov (United States)

    Panah, Faride Gerami; Rezai, Sosan Mir Mohammad; Ahmadian, Leila

    2008-07-01

    An increasing demand for esthetic restorations has resulted in the development of new ceramic systems, but fracture of veneering ceramics still remains the primary cause of failure. Porcelain repair frequently involves replacement with composite resin, but the bond strength between composite resin and all-ceramic coping materials has not been studied extensively. The purpose of this study was to evaluate the influence of different ceramic surface treatments on the micro-shear bond strength of composite resin to IPS Empress 2 coping material. Sixteen 7 x 7 x 1 mm(3) lithia disilicate-based core ceramic plates were fabricated using the lost wax technique. The plates were divided into eight groups, and eight different surface treatments were performed: (1) no treatment (NT); (2) airborne-particle abrasion with 50-mum alumina particles (Al); (3) acid etching with 9.6% hydrofluoric acid for 1 min (HF); (4) silane coating (S); (5) AlHF; (6) AlS; (7) HFS; and (8) AlHFS. Then, ten composite resin cylinders (0.8-mm diameter x 0.5-mm height) were light-polymerized onto the ceramic plates in each group. Each specimen was subjected to a shear load at a crosshead speed of 0.5 mm/min until fracture occurred. The fracture sites were examined with scanning electron microscopy (SEM) to determine the location of failure during debonding and to examine the surface treatment effects. One-way analysis of variance (ANOVA) and multiple comparison (Dunnet T3) tests were used for statistical analysis of data. The mean micro-shear bond strength values (SD) in MPa were--NT: 4.10 (3.06), Al: 7.56 (4.11), HF: 14.04 (2.60), S: 14.58 (2.14), AlHF: 15.56 (3.36), AlS: 23.02 (4.17), HFS: 24.7 (4.43), AlHFS: 26.0 (3.71). ANOVA indicated the influence of surface treatment was significant (p Empress 2 was significantly different depending on the surface treatment method. Among the investigated methods, silane coating after airborne-particle abrasion and etching was the most effective surface treatment

  8. Antithyroid drugs as a factor influencing the outcome of radioiodine therapy in Graves' disease and toxic nodular goitre?

    International Nuclear Information System (INIS)

    Koerber, C.; Schneider, P.; Koerber-Hafner, N.; Haenscheid, H.; Reiners, C.

    2001-01-01

    There is controversy over the factors that may influence the outcome of radioiodine therapy for benign thyroid diseases. Antithyroid medication has been claimed to negatively influence the effectiveness of radioiodine therapy in Graves' disease. In a longitudinal study, we assessed the influence of sex, age, antithyroid drugs, target radiation dose, target mass, applied activity, delivered dose, interval between last meal and application, and TSH, FT 3 and FT 4 levels on the outcome of radioiodine therapy. One hundred and forty-four patients (111 female, 33 male) suffering from Graves' disease (GD) and 563 patients (434 female, 129 male) with toxic nodular goitre (TNG) were entered in the study and followed up until 8 months after therapy. Treatment was defined as successful when the TSH level was found to be normal or elevated. Ninety-eight GD patients and 418 TNG patients were successfully treated. Forward stepwise multiple regression analysis models retained only the target mass in GD and the applied activity in TNG as significantly associated with the outcome of therapy. The predictive value of all variables involved was extremely low in both disease groups. Whereas concomitant antithyroid medication had no influence in GD, it adversely influenced radioiodine therapy of TNG. This effect may be attributed to a radioiodine ''steal phenomenon'' induced by TSH-stimulated normal thyroid tissue, which causes overestimation of the uptake in toxic nodules. (orig.)

  9. Foot drop caused by lumbar degenerative disease: clinical features, prognostic factors of surgical outcome and clinical stage.

    Directory of Open Access Journals (Sweden)

    Kun Liu

    Full Text Available OBJECTIVE: The purpose of this study was to analyze the clinical features and prognostic factors of surgical outcome of foot drop caused by lumbar degenerative disease and put forward the clinical stage. METHODS: We retrospectively reviewed 135 patients with foot drop due to lumbar degenerative disease. The clinical features and mechanism were analyzed. Age, sex, duration of palsy, preoperative muscle strength of tibialis anterior (TA, sensation defect of affected lower limb, affected foot, diagnosis and compressed nerve roots were recorded and compared with surgical outcome. RESULTS: Foot drop was observed in 8.1% of all inpatients of lumbar degenerative disease. L5 nerve root compression was observed in 126 of all 135 patients (93.3%. Single, double and triple roots compression was observed respectively in 43, 83, and 9 patients (31.9%, 61.5%, and 6.6%. But there was no significant relationship between preoperative muscle strength of TA and the number of compressed roots. The muscle strength of TA was improved in 113 (83.7% patients after surgery, but it reached to >=4 in only 21 (15.6% patients. Improvement of the muscle strength of TA was almost stable at the 6-month follow-up. At the last follow-up, the muscle strength of TA was 1, 2, 3, 4, 5 respectively in 28, 24, 62, 13, 8 patients. Multivariate logistic regression showed duration of palsy (p=0.0360, OR=2.543, preoperative muscle strength of TA (p=0.0064, OR=5.528 and age (p=0.0309, OR=3.208 were factors that influenced recovery following an operation. CONCLUSIONS: L5 nerve root was most frequently affected. The muscle strength of TA improved in most patients after surgery, but few patients can get a good recovery from foot drop. Patients of shorter duration of palsy, better preoperative muscle strength of TA and younger age showed a better surgical outcome.

  10. Influence of strength training on cardiac risk prevention in ...

    African Journals Online (AJOL)

    It has widely been shown that exercise, particularly aerobic exercise, has extensive cardioprotective benefits and is an important tool in the prevention of coronary heart disease (CHD). The present investigation aimed to determine the multivariate impact of strength training, designed to prevent the development of CHD, on ...

  11. System effects influencing the bending strength of timber beams

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager; Källsner, B.

    1998-01-01

    A stochastic model of hierarchical series system type for the bending strength of spruce beams isdefined from the anticipation that the bending failure takes place at a cross-section with a defect cluster formed by knots or grain irregularities. The parameters of the model are estimated from meas...

  12. Influence of the mechanical properties of lime mortar on the strength of brick masonry

    OpenAIRE

    PAVIA, SARA

    2013-01-01

    PUBLISHED This paper aims at improving the quality of lime mortar masonry by understanding the mechanics of mortars and masonry and their interaction. It investigates how the mortar?s compressive and flexural strengths impact the compressive and bond strength of clay brick masonry bound with calcium lime (CL) and natural hydraulic lime (NHL) mortars. It concludes that the strength of the bond has a greater impact on the compressive strength of masonry than the mortar?s st...

  13. Strength capability while kneeling.

    Science.gov (United States)

    Haslegrave, C M; Tracy, M F; Corlett, E N

    1997-12-01

    Work sometimes has to be carried out kneeling, particularly where jobs are performed in confined spaces as is common for miners, aircraft baggage handlers and maintenance workers. In order to assess the risks in performing forceful tasks under such conditions, data is needed on strength capabilities of kneeling subjects. A study was undertaken to measure isometric strength in single-handed exertions for male subjects and to investigate the effects on this of task layout factors (direction of force exertion, reach distance, height of the workpiece and orientation relative to the subject's sagittal plane). The data has been tabulated to show the degree to which strength may be reduced in different situations and analysis of the task factors showed their influence to be complex with direction of exertion and reach distance having the greatest effect. The results also suggest that exertions are weaker when subjects are kneeling on two knees than when kneeling on one knee, although this needs to be confirmed by direct experimental comparison.

  14. Influence of atmospheric pressure low-temperature plasma treatment on the shear bond strength between zirconia and resin cement.

    Science.gov (United States)

    Ito, Yuki; Okawa, Takahisa; Fukumoto, Takahiro; Tsurumi, Akiko; Tatsuta, Mitsuhiro; Fujii, Takamasa; Tanaka, Junko; Tanaka, Masahiro

    2016-10-01

    Zirconia exhibits excellent strength and high biocompatibility in technological applications and it is has therefore been investigated for clinical applications and research. Before setting prostheses, a crown prosthesis inner surface is sandblasted with alumina to remove contaminants and form small cavities. This alumina sandblasting causes stress-induced phase transition of zirconia. Atmospheric-pressure low-temperature plasma has been applied in the dental industry, particularly for adhesives, as a surface treatment to activate the surface energy and remove contaminants. The purpose of this study was to examine the influence of atmospheric-pressure low-temperature plasma treatment on the shear bond strength between zirconia and adhesive resin cement. The surface treatment method was classified into three groups: untreated (Cont group), alumina sandblast treatment (Sb group), and atmospheric-pressure low-temperature plasma treatment (Ps group). Adhesive resin cement was applied to stainless steel and bonded to zirconia. Shear adhesion tests were performed after complete hardening of the cement. Multiple comparisons were performed using a one-way analysis of variance and the Bonferroni method. X-ray diffractometry was used to examine the change in zirconia crystal structure. Statistically significant differences were noted between the control and Sb groups and between the control and Ps groups. In contrast, no statistically significant differences were noted for the Ps and Sb bond strength. Atmospheric-pressure low-temperature plasma treatment did not affect the zirconia crystal structure. Atmospheric-pressure low-temperature plasma treatment improves the bonding strength of adhesive resin cement as effectively as alumina sandblasting, and does not alter the zirconia crystal structure. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  15. Influence of glass particle size of resin cements on bonding to glass ceramic: SEM and bond strength evaluation.

    Science.gov (United States)

    Valentini, Fernanda; Moraes, Rafael R; Pereira-Cenci, Tatiana; Boscato, Noéli

    2014-05-01

    This study investigated the effect of the filler particle size (micron or submicron) of experimental resin cements on the microtensile bond strength to a glass-ceramic pretreated with hydrofluoric acid (HFA) etching or alumina airborne-particle abrasion (AA). Cements were obtained from a Bis-GMA/TEGDMA mixture filled with 60 mass% micron-sized (1 ± 0.2 µm) or submicron-sized (180 ± 30 µm) Ba-Si-Al glass particles. Ceramic blocks (PM9; VITA) were treated with 10% HFA for 60 s or AA for 15 s. Silane and adhesive were applied. Ceramic blocks were bonded to resin composite blocks (Z250; 3M ESPE) using one of the cements. Bonded specimens were sectioned into beams (n = 20/group) and subjected to microtensile bond strength tests. Data were analyzed using ANOVA and Student-Newman-Keuls' tests (5%). Failure modes were classified under magnification. Morphologies of the treated ceramic surfaces and bonded interfaces were evaluated by scanning electron microscopy. The HFA-submicron group had lower bond strengths than the other groups. All AA-submicron specimens debonded prematurely. Mixed failures were predominant for HFA groups, whereas interfacial failures predominated for AA groups. SEM revealed a honeycomb-like aspect in the HFA-treated ceramic, whereas the AA-treated groups showed an irregular retentive pattern. Continuity of cement infiltration along the bonded interface was more uniform for HFA-treated compared to AA-treated specimens. Cracks toward the bulk of the ceramic were observed in AA-treated specimens. Particle size significantly influenced the ceramic bond strength, whereas surface treatment had a minor effect. Copyright © 2014 Wiley Periodicals, Inc.

  16. The influence of silane evaporation procedures on microtensile bond strength between a dental ceramic and a resin cement

    Directory of Open Access Journals (Sweden)

    Pereira Carolina

    2010-01-01

    Full Text Available Aim: To assess the influence of silane evaporation procedures on bond strength between a dental ceramic and a chemically activated resin cement. Materials and Methods: Eighteen blocks (6 mm Χ 14 mm Χ 14 mm of ceramic IPS Empress 2 were cemented (C and B to composite resin (InTen-S blocks using a chemical adhesive system (Lok. Six groups were analyzed, each with three blocks divided according to ceramic surface treatment: two control groups (no treatment, NT; 10% hydrofluoric acid plus silane Monobond-S dried at room temperature, HFS; the other four groups comprised different evaporation patterns (silane rinsed and dried at room temperature, SRT; silane rinsed in boiling water and dried as before, SBRT; silane rinsed with boiling water and heat dried at 50°C, SBH; silane dried at 50 ± 5°C, rinsed in boiling water and dried at room temperature, SHBRT. The cemented blocks were sectioned to obtain specimens for microtensile test 7 days after cementation and were stored in water for 30 days prior to testing. Fracture patterns were analyzed by optical and scanning electron microscopy. Statistics and Results: All blocks of NT debonded during sectioning. One way ANOVA tests showed higher bond strengths for HFS than for the other groups. SBRT and SBH were statistically similar, with higher bond strengths than SRT and SHBRT. Failures were 100% adhesive in SRT and SHBRT. Cohesive failures within the "adhesive zone" were detected in HFS (30%, SBRT (24% and SBH (40%. Conclusion: Silane treatment enhanced bond strength in all conditions evaluated, showing best results with HF etching.

  17. Influences of Training on Individual Outcomes for High School Sports Officials

    Directory of Open Access Journals (Sweden)

    Timothy D. Ryan

    2014-04-01

    Full Text Available The primary purpose of this study was to explore the influences of training on specific quality of work outcomes of job satisfaction, pay satisfaction, and intentions to leave within high school sports officials. Evidence suggests that there is a shortage of high school officials in all categories of high school sport. Via a web-based survey, we explored the effects of training on the individual outcomes under study. Results indicated that the level of training had a significant effect on job satisfaction, pay satisfaction, and turnover intentions. Analyses indicated that officials with less training had higher turnover intentions and lower job satisfaction than officials who had more training. Conversely, officials who engaged numerous training hours had lower pay satisfaction. This exploratory study supports the importance of training high school officials but, more importantly, provides an initial assessment on the reverse effects of training on pay satisfaction.

  18. The Influence Of Learning Model Guided Findings Of Student Learning Outcomes

    Directory of Open Access Journals (Sweden)

    A. SaefulBahri

    2015-03-01

    Full Text Available Abstract This study examines the influence of the learning model guided findings on student learning outcomes in subjects PAI eighth grade students of SMP Plus al Masoem. The research method used in this study is a quantitative method in the form of quasi-experiment Quasi-Experimental Design. The findings of the study are expected to demonstrate 1 the difference significant increase in learning outcomes between the experimental class using guided discovery method that uses the control class discussion of learning models 2 Constraints in the method of guided discovery activities and the limited ability of educators in the experimental class in implements the method of guided discovery and constraints faced by students while digging the information they need so we need special strategies to motivate students in the experimental class in order for them creatively find the right way to gather information that supports learning PAI.

  19. Influence of peer review on the reporting of primary outcome(s) and statistical analyses of randomised trials.

    Science.gov (United States)

    Hopewell, Sally; Witt, Claudia M; Linde, Klaus; Icke, Katja; Adedire, Olubusola; Kirtley, Shona; Altman, Douglas G

    2018-01-11

    Selective reporting of outcomes in clinical trials is a serious problem. We aimed to investigate the influence of the peer review process within biomedical journals on reporting of primary outcome(s) and statistical analyses within reports of randomised trials. Each month, PubMed (May 2014 to April 2015) was searched to identify primary reports of randomised trials published in six high-impact general and 12 high-impact specialty journals. The corresponding author of each trial was invited to complete an online survey asking authors about changes made to their manuscript as part of the peer review process. Our main outcomes were to assess: (1) the nature and extent of changes as part of the peer review process, in relation to reporting of the primary outcome(s) and/or primary statistical analysis; (2) how often authors followed these requests; and (3) whether this was related to specific journal or trial characteristics. Of 893 corresponding authors who were invited to take part in the online survey 258 (29%) responded. The majority of trials were multicentre (n = 191; 74%); median sample size 325 (IQR 138 to 1010). The primary outcome was clearly defined in 92% (n = 238), of which the direction of treatment effect was statistically significant in 49%. The majority responded (1-10 Likert scale) they were satisfied with the overall handling (mean 8.6, SD 1.5) and quality of peer review (mean 8.5, SD 1.5) of their manuscript. Only 3% (n = 8) said that the editor or peer reviewers had asked them to change or clarify the trial's primary outcome. However, 27% (n = 69) reported they were asked to change or clarify the statistical analysis of the primary outcome; most had fulfilled the request, the main motivation being to improve the statistical methods (n = 38; 55%) or avoid rejection (n = 30; 44%). Overall, there was little association between authors being asked to make this change and the type of journal, intervention, significance of the

  20. Effectiveness of acute in-hospital physiotherapy with knee-extension strength training in reducing strength deficits in patients with a hip fracture

    DEFF Research Database (Denmark)

    Kronborg, Lise; Bandholm, Thomas; Palm, Henrik

    2017-01-01

    QUESTION: Is acute in-hospital physiotherapy with additional progressive knee-extension strength training (ST) of the fractured limb more effective in reducing knee-extension strength deficit at follow-up compared to physiotherapy without strength training in patients with a hip fracture? DESIGN......: Assessor blinded, randomised controlled trial with intention-to-treat analysis. PARTICIPANTS: 90 patients with a hip fracture admitted to an acute orthopaedic Hip Fracture Unit at a university hospital between October 2013 and May 2015. INTERVENTION: Daily physiotherapy with or without progressive knee...... strength training from baseline to follow-up. In the per-protocol analysis of non-missing data, significant between-group improvements by 10.5% (95% CI 0.3; 20.7) were found in favour of additional ST. No significant between-group differences were found in any secondary outcome. CONCLUSION: Physiotherapy...

  1. Research on the compressive strength of a passenger vehicle roof

    Science.gov (United States)

    Zhao, Guanglei; Cao, Jianxiao; Liu, Tao; Yang, Na; Zhao, Hongguang

    2017-05-01

    To study the compressive strength of a passenger vehicle roof, this paper makes the simulation test on the static collapse of the passenger vehicle roof and analyzes the stress and deformation of the vehicle roof under pressure in accordance with the Roof Crush Resistance of Passenger Cars (GB26134-2010). It studies the optimization on the major stressed parts, pillar A, pillar B and the rail of roof, during the static collapse process of passenger vehicle roof. The result shows that the thickness of pillar A and the roof rail has significant influence on the compressive strength of the roof while that of pillar B has minor influence on the compressive strength of the roof.

  2. Influence of Curing Humidity on the Compressive Strength of Gypsum-Cemented Similar Materials

    Directory of Open Access Journals (Sweden)

    Weiming Guan

    2016-01-01

    Full Text Available The analogous simulation experiment is widely used in geotechnical and mining engineering. However, systematic errors derived from unified standard curing procedure have been underestimated to some extent. In this study, 140 gypsum-cemented similar material specimens were chosen to study their curing procedure with different relative humidity, which is 10%–15%, 40%, 60%, and 80%, respectively. SEM microstructures and XRD spectra were adopted to detect the correlation between microstructures and macroscopic mechanical strength during curing. Our results indicated that the needle-like phases of similar materials began to develop in the early stage of the hydration process through intersecting with each other and eventually transformed into mat-like phases. Increase of humidity may inhibit the development of needle-like phases; thus the compressive strength changes more smoothly, and the time required for the material strength to reach the peak value will be prolonged. The peak strength decreases along with the increase of humidity while the humidity is higher than 40%; however, the reverse tendency was observed if the humidity was lower than 40%. Finally, we noticed that the material strength usually reaches the peak value when the water content continuously reduces and tends towards stability. Based on the above observation, a curing method determination model and experimental strength predication method for gypsum-cemented similar materials were proposed.

  3. Effects of yoga, strength training and advice on back pain: a randomized controlled trial.

    Science.gov (United States)

    Brämberg, Elisabeth Björk; Bergström, Gunnar; Jensen, Irene; Hagberg, Jan; Kwak, Lydia

    2017-03-29

    Among the working population, non-specific low-back pain and neck pain are one of the most common reasons for sickness absenteeism. The aim was to evaluate the effects of an early intervention of yoga - compared with strength training or evidence-based advice - on sickness absenteeism, sickness presenteeism, back and neck pain and disability among a working population. A randomized controlled trial was conducted on 159 participants with predominantly (90%) chronic back and neck pain. After screening, the participants were randomized to kundalini yoga, strength training or evidence-based advice. Primary outcome was sickness absenteeism. Secondary outcomes were sickness presenteeism, back and neck pain and disability. Self-reported questionnaires and SMS text messages were completed at baseline, 6 weeks, 6 and 12 months. The results did not indicate that kundalini yoga and strength training had any statistically significant effects on the primary outcome compared with evidence-based advice. An interaction effect was found between adherence to recommendations and sickness absenteeism, indicating larger significant effects among the adherers to kundalini yoga versus evidence-based advice: RR = 0.47 (CI 0.30; 0.74, p = 0.001), strength training versus evidence-based advice: RR = 0.60 (CI 0.38; 0.96, p = 0.032). Some significant differences were also found for the secondary outcomes to the advantage of kundalini yoga and strength training. Guided exercise in the forms of kundalini yoga or strength training does not reduce sickness absenteeism more than evidence-based advice alone. However, secondary analyses reveal that among those who pursue kundalini yoga or strength training at least two times a week, a significantly reduction in sickness absenteeism was found. Methods to increase adherence to treatment recommendations should be further developed and applied in exercise interventions. Clinicaltrials.gov NCT01653782, date of registration: June, 28

  4. The strength of polyaxial locking interfaces of distal radius plates.

    Science.gov (United States)

    Hoffmeier, Konrad L; Hofmann, Gunther O; Mückley, Thomas

    2009-10-01

    Currently available polyaxial locking plates represent the consequent enhancement of fixed-angle, first-generation locking plates. In contrast to fixed-angle locking plates which are sufficiently investigated, the strength of the new polyaxial locking options has not yet been evaluated biomechanically. This study investigates the mechanical strength of single polyaxial interfaces of different volar radius plates. Single screw-plate interfaces of the implants Palmar 2.7 (Königsee Implantate und Instrumente zur Osteosynthese GmbH, Allendorf, Germany), VariAx (Stryker Leibinger GmbH & Co. KG, Freiburg, Germany) und Viper (Integra LifeSciences Corporation, Plainsboro, NJ, USA) were tested by cantilever bending. The strength of 0 degrees, 10 degrees and 20 degrees screw locking angle was obtained during static and dynamic loading. The Palmar 2.7 interfaces showed greater ultimate strength and fatigue strength than the interfaces of the other implants. The strength of the VariAx interfaces was about 60% of Palmar 2.7 in both, static and dynamic loading. No dynamic testing was applied to the Viper plate because of its low ultimate strength. By static loading, an increase in screw locking angle caused a reduction of strength for the Palmar 2.7 and Viper locking interfaces. No influence was observed for the VariAx locking interfaces. During dynamic loading; angulation had no influence on the locking strength of Palmar 2.7. However, reduction of locking strength with increasing screw angulation was observed for VariAx. The strength of the polyaxial locking interfaces differs remarkably between the examined implants. Depending on the implant an increase of the screw locking angle causes a reduction of ultimate or fatigue strength, but not in all cases a significant impact was observed.

  5. Is gender influencing the biomechanical results after autologous chondrocyte implantation?

    Science.gov (United States)

    Kreuz, Peter C; Müller, Sebastian; Erggelet, Christoph; von Keudell, Arvind; Tischer, Thomas; Kaps, Christian; Niemeyer, Philipp; Hirschmüller, Anja

    2014-01-01

    The influence of gender on the biomechanical outcome after autologous chondrocyte implantation (ACI) including isokinetic muscle strength measurements has not been investigated. The present prospective study was performed to evaluate gender-specific differences in the biomechanical function 48 months after ACI. Fifty-two patients (mean age 35.6 ± 8.5 years) that met our inclusion criteria, underwent ACI with Bioseed C(®) and were evaluated with the KOOS score preoperatively, 6, 12 and 48 months after surgery. At final follow-up, 44 out of the 52 patients underwent biomechanical evaluation with isokinetic strength measurements of both knees. All data were evaluated separately for men and women and compared for each time interval using the Mann-Whitney U test. Clinical scores improved significantly over the whole study period (p genders. Isokinetic muscle strength measures are significantly worse in women (p role for the explanation of gender-specific results after ACI.

  6. Influence of casting defects on fatigue strength of an investment cast Ti-6Al-4V alloy

    Directory of Open Access Journals (Sweden)

    Léopold Gaëlle

    2014-06-01

    Full Text Available The influence of casting defects on fatigue strength of an investment cast Ti-6Al-4V alloy is investigated. The most common of these defects are: pinhole, linear defect and inclusion. Each of them is currently defined by its size, morphology and position from the surface but is different from each other for a same type. An experimental campaign is defined with different types of defect. The first part of the campaign is focused on the influence of an artificial and spherical defect, considering two different surface conditions. It is shown that fatigue behaviour of this alloy is very sensitive to the surface condition of this artificial defect despite stress concentrations at the tip of the defect. The second part of the campaign is focused on casting defects: reduction of fatigue life is quantified and it is shown that an electro-discharge machined defect cannot be representative of pinhole.

  7. The influence of neck thrombus on clinical outcome and aneurysm morphology after endovascular aneurysm repair

    NARCIS (Netherlands)

    F.M.V. Bastos Gonçalves (Frederico); H.J.M. Verhagen (Hence); K. Chinsakchai (Khamin); J.W. van Keulen (Jasper); M.T. Voûte (Michiel); H.J.A. Zandvoort (Herman); F.L. Moll (Frans); J.A. van Herwaarden (Joost)

    2012-01-01

    textabstractObjective: This study investigated the influence of significant aneurysm neck thrombus in clinical and morphologic outcomes after endovascular aneurysm repair (EVAR). Methods: The patient population was derived from a prospective EVAR database from two university institutions in The

  8. The Influence of Methotrexate Treatment on Male Fertility and Pregnancy Outcome After Paternal Exposure.

    Science.gov (United States)

    Grosen, Anne; Kelsen, Jens; Hvas, Christian Lodberg; Bellaguarda, Emanuelle; Hanauer, Stephen B

    2017-04-01

    Inflammatory bowel disease incidence peaks during the reproductive years. Methotrexate (MTX) is frequently used for inflammatory bowel disease, but its use during pregnancy is contraindicated in women because of teratogenic effects. The aim of this review is to investigate the influence of MTX on male fertility and pregnancy outcomes after paternal MTX exposure. A systematic literature search was performed by applying 2 focus areas, "methotrexate" and "male fertility or pregnancy outcome." Terms and keywords were used both as MeSH terms and free-text searches. Pertinent articles were searched for additional relevant references. In animal studies, MTX induces aberrations in sperm DNA that have not been identified in humans. The effects of MTX on human sperm quality have only been described in case reports. A transient adverse effect on sperm quality with low-dose MTX has been reported, but several other cases have not found harmful effects of MTX. MTX has not been measured in human sperm ejaculates; yet, the risk of a direct toxic effect on the fetus through MTX-contaminated seminal plasma seems negligible. Until now, 284 pregnancies with paternal MTX exposure have been reported. The outcomes were 248 live births and a total of 13 malformations, with no overt indication of MTX embryopathy. This review reveals the lack of studies on the safety of MTX with regard to male reproduction. It is not clear whether MTX transiently influences male fertility and sperm DNA integrity, and more studies are needed. Comparative cohort studies found no increased risk of adverse pregnancy outcomes.

  9. Comorbidity negatively influences the outcomes of diagnostic tests for musculoskeletal pain in the orofacial region.

    Science.gov (United States)

    Koutris, Michail; Visscher, Corine M; Lobbezoo, Frank; Naeije, Machiel

    2013-06-01

    The aim of this study was to investigate whether diagnostic tests for musculoskeletal pain in the orofacial region [temporomandibular disorder (TMD) pain] are influenced by the presence of comorbid conditions, and to determine whether this influence decreases when the presence of "familiar pain" is used as outcome measure. In total, 117 patients (35 men, 82 women; 75 TMD-pain patients, 42 pain-free patients; mean age ± SD = 42.94 ± 14.17 years) were examined with palpation tests and dynamic/static tests. After each test, they were asked whether any pain was provoked and whether this pain response was familiar or not. For four clinical outcome measures (pain on palpation, familiar pain on palpation, pain on dynamic/static tests, and familiar pain on dynamic/static tests), multiple logistic regression analyses were performed with the presence of TMD pain as the primary predictor and regional (neck/shoulder) pain, widespread pain, depression, and somatization as comorbid factors. Pain on palpation was not associated with the primary predictor but with regional pain [P = 0.02, odds ratio (OR) = 4.59] and somatization (P = 0.011, OR = 8.47), whereas familiar pain on palpation was associated with the primary predictor (P = 0.003, OR = 5.23), but also with widespread pain (P = 0.001, OR = 2.02). Pain on dynamic/static tests was associated with the primary predictor (P pain on dynamic/static tests was only associated with the primary predictor (P diagnostic tests are negatively influenced by the presence of comorbidity. This influence decreases when the presence of familiar pain is used as outcome measure. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  10. Effect of surface treatment on flexural strength of zirconia bars

    NARCIS (Netherlands)

    Aboushelib, M.N.; Wang, H.

    2010-01-01

    Statement of problem Clinical and laboratory processing techniques induce damage to the surface of zirconia frameworks, which significantly lessens their strength. Purpose The purpose of this study was to investigate the influence of 3 surface restoration methods on the flexural strength of zirconia

  11. The geomechanical strength of carbonate rock in Kinta valley, Ipoh, Perak Malaysia

    Science.gov (United States)

    Mazlan, Nur Amanina; Lai, Goh Thian; Razib, Ainul Mardhiyah Mohd; Rafek, Abdul Ghani; Serasa, Ailie Sofyiana; Simon, Norbert; Surip, Noraini; Ern, Lee Khai; Mohamed, Tuan Rusli

    2018-04-01

    The stability of both cut rocks and underground openings were influenced by the geomechanical strength of rock materials, while the strength characteristics are influenced by both material characteristics and the condition of weathering. This paper present a systematic approach to quantify the rock material strength characteristics for material failure and material & discontinuities failure by using uniaxial compressive strength, point load strength index and Brazilian tensile strength for carbonate rocks. Statistical analysis of the results at 95 percent confidence level showed that the mean value of compressive strength, point load strength index and Brazilian tensile strength for with material failure and material & discontinuities failure were 76.8 ± 4.5 and 41.2 ± 4.1 MPa with standard deviation of 15.2 and 6.5 MPa, respectively. The point load strength index for material failure and material & discontinuities failure were 3.1 ± 0.2 MPa and 1.8 ± 0.3 MPa with standard deviation of 0.9 and 0.6 MPa, respectively. The Brazilian tensile strength with material failure and material & discontinuities failure were 7.1 ± 0.3 MPa and 4.1 ± 0.3 MPa with standard deviation of 1.4 and 0.6 MPa, respectively. The results of this research revealed that the geomechanical strengths of rock material of carbonate rocks for material & discontinuities failure deteriorates approximately ½ from material failure.

  12. A Systematic Review of the Effect of Cognitive Strategies on Strength Performance.

    Science.gov (United States)

    Tod, David; Edwards, Christian; McGuigan, Mike; Lovell, Geoff

    2015-11-01

    Researchers have tested the beliefs of sportspeople and sports medicine specialists that cognitive strategies influence strength performance. Few investigators have synthesised the literature. The specific objectives were to review evidence regarding (a) the cognitive strategy-strength performance relationship; (b) participant skill level as a moderator; and (c) cognitive, motivational, biomechanical/physiological, and emotional mediators. Studies were sourced via electronic databases, reference lists of retrieved articles, and manual searches of relevant journals. Studies had to be randomised or counterbalanced experiments with a control group or condition, repeated measures, and a quality control score above 0.5 (out of 1). Cognitive strategies included goal setting, imagery, self-talk, preparatory arousal, and free choice. Dependent variables included maximal strength, local muscular endurance, or muscular power. Globally, cognitive strategies were reliability associated with increased strength performance (results ranged from 61 to 65 %). Results were mixed when examining the effects of specific strategies on particular dependent variables, although no intervention had an overall negative influence. Indeterminate relationships emerged regarding hypothesised mediators (except cognitive variables) and participant skill level as a moderator. Although cognitive strategies influence strength performance, there are knowledge gaps regarding specific types of strength, especially muscular power. Cognitive variables, such as concentration, show promise as possible mediators.

  13. The influence of poly(acrylic) acid number average molecular weight and concentration in solution on the compressive fracture strength and modulus of a glass-ionomer restorative.

    LENUS (Irish Health Repository)

    Dowling, Adam H

    2011-06-01

    The aim was to investigate the influence of number average molecular weight and concentration of the poly(acrylic) acid (PAA) liquid constituent of a GI restorative on the compressive fracture strength (σ) and modulus (E).

  14. How much muscle strength is required to walk in a crouch gait?

    NARCIS (Netherlands)

    Steele, K.M.; van der Krogt, M.M.; Schwartz, M.H.; Delp, S.L.

    2012-01-01

    Muscle weakness is commonly cited as a cause of crouch gait in individuals with cerebral palsy; however, outcomes after strength training are variable and mechanisms by which muscle weakness may contribute to crouch gait are unclear. Understanding how much muscle strength is required to walk in a

  15. The Influence of No Fault Compensation on Functional Outcomes After Lumbar Spine Fusion.

    Science.gov (United States)

    Montgomery, Alexander Sheriff; Cunningham, John Edward; Robertson, Peter Alexander

    2015-07-15

    compared with the dramatically inferior outcomes for these patients under other worker's compensation systems, suggest that the system of compensation has a major influence on patient outcomes, and that change of compensation to a universal no fault system is beneficial for patients undergoing lumbar fusion surgery. 2.

  16. The strength of primary care in Europe

    NARCIS (Netherlands)

    Kringos, D.S.|info:eu-repo/dai/nl/352077131

    2012-01-01

    This thesis aimed to get insight into the elements that form (the strength of) primary care (PC) in Europe, their determinants and their impact on health care system outcomes. The results strengthen the evidence-base for policymakers to prioritise PC strengthening on the health policy agenda and

  17. [Influence of retainer design on fixation strength of resin-bonded glass fiber reinforced composite fixed cantilever dentures].

    Science.gov (United States)

    Petrikas, O A; Voroshilin, Iu G; Petrikas, I V

    2013-01-01

    Fiber-reinforced composite (FRC) fixed partial dentures (FPD) have become an accepted part of the restorative dentist's armamentarium. The aim of this study was to evaluate in vitro the influence of retainer design on the strength of two-unit cantilever resin-bonded glass FRC-FPDs. Four retainer designs were tested: a dual wing, a dual wing + horizontal groove, a dual wing + occlusal rest and a step-box. Of each design on 7 human mandibular molars, FRC-FPDs of a premolar size were produced. The FRC framework was made of resin Revolution (Kerr) impregnated glass fibers (GlasSpan, GlasSpan) and veneered with hybrid resin composite (Charisma, Kulzer). Revolution (Kerr) was used as resin luting cement. FRC-FPDs were loaded to failure in a universal testing machine. T (Student's)-test was used to evaluate the data. The four designs were analyzed with finite element analysis (FEA) to reveal the stress distribution within the tooth/restoration complex. Significantly lower fracture strengths were observed with inlay-retained FPDs (step-box: 172±11 N) compared to wing-retained FPDs (poptimal design for replacement of a single premolar by means of a two-unit cantilever FRC-FPDs.

  18. Sources of Life Strengths Appraisal Scale: A Multidimensional Approach to Assessing Older Adults’ Perceived Sources of Life Strengths

    Directory of Open Access Journals (Sweden)

    Prem S. Fry

    2014-01-01

    Full Text Available Both cognitive and psychosocial theories of adult development stress the fundamental role of older adults’ appraisals of the diverse sources of cognitive and social-emotional strengths. This study reports the development of a new self-appraisal measure that incorporates key theoretical dimensions of internal and external sources of life strengths, as identified in the gerontological literature. Using a pilot study sample and three other independent samples to examine older adults’ appraisals of their sources of life strengths which helped them in their daily functioning and to combat life challenges, adversity, and losses, a psychometric instrument having appropriate reliability and validity properties was developed. A 24-month followup of a randomly selected sample confirmed that the nine-scale appraisal measure (SLSAS is a promising instrument for appraising older adults’ sources of life strengths in dealing with stresses of daily life’s functioning and also a robust measure for predicting outcomes of resilience, autonomy, and well-being for this age group. A unique strength of the appraisal instrument is its critically relevant features of brevity, simplicity of language, and ease of administration to frail older adults.

  19. Aquatic Therapy Improves Outcomes for Subacute Stroke Patients by Enhancing Muscular Strength of Paretic Lower Limbs Without Increasing Spasticity: A Randomized Controlled Trial.

    Science.gov (United States)

    Zhang, Yue; Wang, Yi-Zhao; Huang, Li-Ping; Bai, Bei; Zhou, Shi; Yin, Miao-Miao; Zhao, Hua; Zhou, Xiao-Na; Wang, Hong-Tu

    2016-11-01

    The aim of this study was to evaluate the effects of an aquatic exercise program designed to enhance muscular strength in paretic lower limbs in subacute stroke patients. Thirty-six subacute stroke patients were randomly divided to a conventional or an aquatic group (n = 18 each). Outcome measures were assessed at baseline and after 8 wks of training. For the paretic lower limbs, maximum isometric voluntary contraction strength of the rectus femoris and biceps femoris caput longus and the tibialis anterior and lateral gastrocnemius was measured. Cocontraction ratios during knee extension and flexion and ankle dorsiflexion and plantarflexion were calculated respectively. In addition, Modified Ashworth Scale, Functional Ambulation Category, and Barthel Index were assessed. Compared with the conventional intervention, the aquatic intervention resulted in significantly higher knee extension (P = 0.002) and ankle plantarflexion torque (P = 0.002), accompanied with a significantly lower knee extension cocontraction ratio in the paretic limb (P = 0.000). Functional Ambulation Category (P = 0.009) and Barthel Index (P = 0.024) were greater in aquatic group than conventional group posttreatment. Modified Ashworth Scale scores did not show any differences between groups. Aquatic exercise enhanced muscle strength in paretic lower limbs and improved muscle cocontraction without increasing spasticity in subacute stroke patients.

  20. Influence of diabetes and hyperglycaemia on infectious disease hospitalisation and outcome

    DEFF Research Database (Denmark)

    Benfield, Thomas; Jensen, J S; Nordestgaard, B G

    2007-01-01

    AIMS/HYPOTHESIS: Diabetes mellitus is believed to increase susceptibility to infectious diseases. The effects of hyperglycaemia per se on infectious disease risk are unknown and the influence of diabetes on infectious disease outcome is controversial. MATERIALS AND METHODS: We studied 10......,063 individuals from the Danish general population, who were participants in The Copenhagen City Heart Study, over a follow-up period of 7 years. Risk of hospitalisation caused by any infectious disease, and subsequent risk of disease progression to death were estimated by Cox proportional hazards regression...

  1. A conceptual framework for studying the strength of plant-animal mutualistic interactions.

    Science.gov (United States)

    Vázquez, Diego P; Ramos-Jiliberto, Rodrigo; Urbani, Pasquinell; Valdovinos, Fernanda S

    2015-04-01

    The strength of species interactions influences strongly the structure and dynamics of ecological systems. Thus, quantifying such strength is crucial to understand how species interactions shape communities and ecosystems. Although the concepts and measurement of interaction strength in food webs have received much attention, there has been comparatively little progress in the context of mutualism. We propose a conceptual scheme for studying the strength of plant-animal mutualistic interactions. We first review the interaction strength concepts developed for food webs, and explore how these concepts have been applied to mutualistic interactions. We then outline and explain a conceptual framework for defining ecological effects in plant-animal mutualisms. We give recommendations for measuring interaction strength from data collected in field studies based on a proposed approach for the assessment of interaction strength in plant-animal mutualisms. This approach is conceptually integrative and methodologically feasible, as it focuses on two key variables usually measured in field studies: the frequency of interactions and the fitness components influenced by the interactions. © 2015 John Wiley & Sons Ltd/CNRS.

  2. The influence of groundwater flow effect on changes of loess soil strength characteristics

    Directory of Open Access Journals (Sweden)

    Bida S.V.

    2015-09-01

    Full Text Available The problem of stability of slopes - one of the most topical at present. It is proved that the reliability of the slope stability assessment affects the accuracy of the strength characteristics of the soil. One of the most common methods is one-plane shifts method Established that processing of results of soil shift test in logarithmic coordinates can more accurately identify indicators of strength. Discovered that the magnitude of the strength characteristics of soil test results which is obtained on one plane shift depends on the vertical pressure during testing.

  3. The influence of tracheostomy timing on outcomes in trauma patients: A meta-analysis.

    Science.gov (United States)

    Cai, Shi-Qi; Hu, Jun-Wu; Liu, Dong; Bai, Xiang-Jun; Xie, Jie; Chen, Jia-Jun; Yang, Fan; Liu, Tao

    2017-04-01

    This study aims to assess the influence of tracheostomy timing on outcomes among trauma patients, including mortality, medical resource utility and incidence of pneumonia. A systematic review of the literature was conducted by internet search. Data were extracted from selected studies and analyzed using Stata to compare outcomes in trauma patients with early tracheostomy (ET) or late tracheostomy (LT)/prolonged intubation (PI). 20 studies met our inclusion criteria with 3305 patients in ET group and 4446 patients in LT/PI group. Pooled data revealed that mortality was not lower in trauma patients with ET compared to those with LT/IP. However, ET was found to be associated with a significantly reduced length of ICU and hospital stay, shorter MV duration and lower risk of pneumonia. Evidence of this meta-analysis supports the dimorphism in some clinical outcomes of trauma patients with different tracheostomy timing. Additional well-designed randomized controlled trials (RCTs) are needed to confirm it in future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Influence of different luting protocols on shear bond strength of computer aided design/computer aided manufacturing resin nanoceramic material to dentin.

    Science.gov (United States)

    Poggio, Claudio; Pigozzo, Marco; Ceci, Matteo; Scribante, Andrea; Beltrami, Riccardo; Chiesa, Marco

    2016-01-01

    The purpose of this study was to evaluate the influence of three different luting protocols on shear bond strength of computer aided design/computer aided manufacturing (CAD/CAM) resin nanoceramic (RNC) material to dentin. In this in vitro study, 30 disks were milled from RNC blocks (Lava Ultimate/3M ESPE) with CAD/CAM technology. The disks were subsequently cemented to the exposed dentin of 30 recently extracted bovine permanent mandibular incisors. The specimens were randomly assigned into 3 groups of 10 teeth each. In Group 1, disks were cemented using a total-etch protocol (Scotchbond™ Universal Etchant phosphoric acid + Scotchbond Universal Adhesive + RelyX™ Ultimate conventional resin cement); in Group 2, disks were cemented using a self-etch protocol (Scotchbond Universal Adhesive + RelyX™ Ultimate conventional resin cement); in Group 3, disks were cemented using a self-adhesive protocol (RelyX™ Unicem 2 Automix self-adhesive resin cement). All cemented specimens were placed in a universal testing machine (Instron Universal Testing Machine 3343) and submitted to a shear bond strength test to check the strength of adhesion between the two substrates, dentin, and RNC disks. Specimens were stressed at a crosshead speed of 1 mm/min. Data were analyzed with analysis of variance and post-hoc Tukey's test at a level of significance of 0.05. Post-hoc Tukey testing showed that the highest shear strength values (P adhesives) showed better shear strength values compared to self-adhesive resin cements. Furthermore, conventional resin cements used together with a self-etch adhesive reported the highest values of adhesion.

  5. Effect of curing time on microstructure and mechanical strength ...

    Indian Academy of Sciences (India)

    The aim of this paper is to study the influence of curing time on the microstructure and mechanical strength development of alkali activated binders based on vitreous calcium aluminosilicate (VCAS). Mechanical strength of alkali activated mortars cured at 65 °C was assessed for different curing times (4–168 h) using 10 ...

  6. Quality of life outcomes in women with endometriosis are highly influenced by recruitment strategies.

    Science.gov (United States)

    De Graaff, A A; Dirksen, C D; Simoens, S; De Bie, B; Hummelshoj, L; D'Hooghe, T M; Dunselman, G A J

    2015-06-01

    To what extent are outcome measures in endometriosis-related quality of life studies influenced by the setting in which patient recruitment is performed? Quality of life outcomes in women with endometriosis are highly influenced by recruitment strategies. Most studies on quality of life in women with endometriosis are conducted in tertiary care centres or patient associations. It is conceivable that the setting in which patient recruitment is performed influences the quality of life results. This has not been investigated before. Retrospective questionnaire based cohort study (part of the World Endometriosis Research Foundation (WERF) EndoCost study). The investigated women were recruited in three settings: a tertiary care centre for endometriosis (n = 135); five secondary care centres (n = 63); an endometriosis patient association (n = 291). The secondary and tertiary care population included women with a laparoscopic and/or histological diagnosis of endometriosis. The patient association population consisted of women with a self-reported diagnosis of surgically confirmed endometriosis. The populations did not differ in terms of age, co-morbidities and education level. Delay of diagnosis was the longest in the patient association (median 7 years) (tertiary care 2 years; secondary care 1.5 years) (P values were analysed as if the symptom was not present. Missing values never exceeded 10%, except for one value. Therefore, it can be expected that the effect of missing data on the outcome is negligible. Twenty-five patients belonged to more than one category. A sensitivity analysis showed that the influence of assigning patients to another category was limited. Outcomes regarding quality of life are highly influenced by recruitment strategy. None of the groups appeared to be a representative selection of the total population of women with endometriosis. An alternative strategy for creating a representative population for cost and quality of life studies is probably to

  7. Assessment of Outcomes of Treatment of Fractures of Distal Femur with a Locking Plate Taking into Account Factors Influencing the Result.

    Science.gov (United States)

    Pakuła, Grzegorz; Kwiatkowski, Krzysztof; Kuczmera, Piotr; Fudalej, Piotr

    2015-10-01

    The aim of this paper is to evaluate the results of treatment of distal femoral fractures (DFF) fixed with locking plates and analysis of factors that influence the final outcome. The patients were treated at the Department of Traumatology and Orthopedics, Military Medical Institute in Warsaw, and the Department of Orthopedics and Traumatology, 4th Military Research Hospital in Wroclaw. We analysed 39 patients with 42 fractures of the distal femur. Treatment results were analysed using the KOOS and KSS scales. Factors influencing the outcome were also investigated. Statistical analysis was performed using STATISTICA v. 10. Mean KOOS scores indicate a predominance of poor outcomes, while mean KSS scores indicate good outcomes. Treatment outcomes were significantly influenced by pain and limited mobility. 1. Subjective evaluation of treatment of fractures of the distal femur using the KOOS scale per form edworse than a clinical evaluation using the KSS. 2. Post-operative management should emphasise pain relief and restoration of the performance of the treated lower limb to ensure good mobility without crutches. 3. Despite the use of modern operational methods of fracture fixation, treatment of distal femur fractures is still a challenge.

  8. The Level of Alexithymia in Alcohol-Dependent Patients Does Not Influence Outcomes after Inpatient Treatment

    NARCIS (Netherlands)

    Haan, H.A. de; Schellekens, A.F.A.; Palen, J.A.M. van der; Verkes, R.J.; Buitelaar, J.K.; Jong, C.A.J. de

    2012-01-01

    Background: The inability of individuals with Alcohol Use Disorders (AUD) to recognize and describe their feelings and cravings may be due to alexithymia. Previous researches have shown evidence for a negative influence of alexithymia on treatment outcomes in patients with AUD. Therefore, it was

  9. The level of alexithymia in alcohol-dependent patients does not influence outcomes after inpatient treatment.

    NARCIS (Netherlands)

    Haan, H.A. de; Schellekens, A.F.A.; Palen, J.A.M. van der; Verkes, R.J.; Buitelaar, J.K.; Jong, C.A.J. de

    2012-01-01

    BACKGROUND: The inability of individuals with Alcohol Use Disorders (AUD) to recognize and describe their feelings and cravings may be due to alexithymia. Previous researches have shown evidence for a negative influence of alexithymia on treatment outcomes in patients with AUD. Therefore, it was

  10. The level of Alexithymia in alcohol-dependent patients does not influence outcomes after inpatient treatment

    NARCIS (Netherlands)

    de Haan, Hein A.; Schellekens, Arnt F.A.; van der Palen, Jacobus Adrianus Maria; Verkes, Robbert-Jan; Buitelaar, Jan K.; de Jong, Cor A.J.

    2012-01-01

    Background: The inability of individuals with Alcohol Use Disorders (AUD) to recognize and describe their feelings and cravings may be due to alexithymia. Previous researches have shown evidence for a negative influence of alexithymia on treatment outcomes in patients with AUD. Therefore, it was

  11. Influence of superplasticizer on microstructure of a 40 MPa strength concrete; Influencia do aditivo superplastificante na microestrutura de um concreto de resistencia mecanica de 40 MPa

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Sandra M.F.; Menezes, Raquel Maria R.O.; Figueiredo, Roberto B.; Aguilar, Maria Teresa P. [Universidade Federal de Minas Gerais (UFMG), MG (Brazil); Franca, Fabricio Carlos [LafargeHolcim, Rio de Janeiro, RJ (Brazil); Bezerra, Augusto Cesar da S. [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), MG (Brazil)

    2016-07-01

    The self compacting concrete has high fluidity and deformability. Studies analyze its performance through compressive strength, mortar content and / or water cement factor, which does not allow the evaluation of superplasticante influence the microstructure of these concretes. In this work, we evaluated the influence of superplasticizer comparing the phases present in a self-compacting concrete 40 MPa and at a same conventional compressive strength, same water / cement and mortar content. Therefore, scanning techniques were employed by electron microscope low vacuum using backscattered electrons and thermal analysis. The observed results show no significant differences in the microstructure of the two composites, ie the superplasticizer does not alter the microstructure of the self-compacting concrete. However, thermal analysis indicates that the present self-compacting concrete greater calcium hydroxide content which may suggest a lower content of such dry cement concrete. (author)

  12. Impact of pain reported during isometric quadriceps muscle strength testing in people with knee pain: data from the osteoarthritis initiative.

    Science.gov (United States)

    Riddle, Daniel L; Stratford, Paul W

    2011-10-01

    Muscle force testing is one of the more common categories of diagnostic tests used in clinical practice. Clinicians have little evidence to guide interpretations of muscle force tests when pain is elicited during testing. The purpose of this study was to examine the construct validity of isometric quadriceps muscle strength tests by determining whether the relationship between maximal isometric quadriceps muscle strength and functional status was influenced by pain during isometric testing. A cross-sectional design was used. Data from the Osteoarthritis Initiative were used to identify 1,344 people with unilateral knee pain and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale scores of 1 or higher on the involved side. Measurements of maximal isometric quadriceps strength and ratings of pain during isometric testing were collected. Outcome variables were WOMAC physical function subscale, 20-m walk test, 400-m walk test, and a repeated chair stand test. Multiple regression models were used to determine whether pain during testing modified or confounded the relationship between strength and functional status. Pearson r correlations among the isometric quadriceps strength measures and the 4 outcome measures ranged from -.36 (95% confidence interval=-.41, -.31) for repeated chair stands to .36 (95% confidence interval=.31, .41) for the 20-m walk test. In the final analyses, neither effect modification nor confounding was found for the repeated chair stand test, the 20-m walk test, the 400-m walk test, or the WOMAC physical function subscale. Moderate or severe pain during testing was weakly associated with reduced strength, but mild pain was not. The disease spectrum was skewed toward mild or moderate symptoms, and the pain measurement scale used during muscle force testing was not ideal. Given that the spectrum of the sample was skewed toward mild or moderate symptoms and disease, the data suggest that isometric quadriceps muscle

  13. Social Support Influences on Substance Abuse Outcomes among Sober Living House Residents with Low and Moderate Psychiatric Severity

    Science.gov (United States)

    Polcin, Douglas L.; Korcha, Rachael

    2017-01-01

    Social support and psychiatric severity are known to influence substance abuse. However, little is known about how their influences vary under different conditions. We aimed to study how different types of social support were associated with substance abuse outcomes among persons with low and moderate psychiatric severity who entered Sober Living…

  14. Influence of application methods of one-step self-etching adhesives on microtensile bond strength

    Directory of Open Access Journals (Sweden)

    Chul-Kyu Choi,

    2011-05-01

    Full Text Available Objectives The purpose of this study was to evaluate the effect of various application methods of one-step self-etch adhesives to microtensile resin-dentin bond strength. Materials and Methods Thirty-six extracted human molars were used. The teeth were assigned randomly to twelve groups (n = 15, according to the three different adhesive systems (Clearfil Tri-S Bond, Adper Prompt L-Pop, G-Bond and application methods. The adhesive systems were applied on the dentin as follows: 1 The single coating, 2 The double coating, 3 Manual agitation, 4 Ultrasonic agitation. Following the adhesive application, light-cure composite resin was constructed. The restored teeth were stored in distilled water at room temperature for 24 hours, and prepared 15 specimens per groups. Then microtensile bond strength was measured and the failure mode was examined. Results Manual agitation and ultrasonic agitation of adhesive significantly increased the microtensile bond strength than single coating and double coating did. Double coating of adhesive significantly increased the microtensile bond strength than single coating did and there was no significant difference between the manual agitation and ultrasonic agitation group. There was significant difference in microtensile bonding strength among all adhesives and Clearfil Tri-S Bond showed the highest bond strength. Conclusions In one-step self-etching adhesives, there was significant difference according to application methods and type of adhesives. No matter of the material, the manual or ultrasonic agitation of the adhesive showed significantly higher microtensile bond strength.

  15. Influence of surface treatment on shear bond strength of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Ione Helena Vieira Portella Brunharo

    2013-06-01

    Full Text Available INTRODUCTION: The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed. METHODS: Two hundred and eighty test samples were divided into 28 groups (n = 10, where 140 specimens were filled with Durafill micro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane was applied. The surface treatment methods were: Phosphoric and hydrofluoric acid etching, sodium bicarbonate and aluminum oxide blasting, stone and burs. A Universal Instron Machine was used to apply an occlusal shear force directly to the resin composite bracket surface at a speed of 0.5 mm/min. The means were compared using analysis of variance and multivariate regression to assess the interaction between composites and surface treatment methods. RESULTS: Means and standard deviations for the groups were: Sodium bicarbonate jet 11.27±2.78; burs 9.26±3.01; stone 7.95±3.67; aluminum oxide blasting 7.04±3.21; phosphoric acid 5.82±1.90; hydrofluoric acid 4.54±2.87, and without treatment 2.75±1.49. An increase of 1.94 MPa in shear bond strength was seen in Charisma groups. Silane agent application reduced the Charisma shear bond strength by 0.68 Mpa, but increased Durafill means for bicarbonate blasting (0.83, burs (0.98 and stone drilling (0.46. CONCLUSION: The sodium bicarbonate blasting, burs and stone drilling methods produced adequate shear bond strength and may be suitable for clinical use. The Charisma micro hybrid resin composite showed higher shear bond means than Durafill micro particle composite.

  16. Influence of surface treatment on shear bond strength of orthodontic brackets.

    Science.gov (United States)

    Brunharo, Ione Helena Vieira Portella; Fernandes, Daniel Jogaib; de Miranda, Mauro Sayão; Artese, Flavia

    2013-01-01

    The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed. Two hundred and eighty test samples were divided into 28 groups (n = 10), where 140 specimens were filled with Durafill micro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane) was applied. The surface treatment methods were: Phosphoric and hydrofluoric acid etching, sodium bicarbonate and aluminum oxide blasting, stone and burs. A Universal Instron Machine was used to apply an occlusal shear force directly to the resin composite bracket surface at a speed of 0.5 mm/min. The means were compared using analysis of variance and multivariate regression to assess the interaction between composites and surface treatment methods. Means and standard deviations for the groups were: Sodium bicarbonate jet 11.27 ± 2.78; burs 9.26 ± 3.01; stone 7.95 ± 3.67; aluminum oxide blasting 7.04 ± 3.21; phosphoric acid 5.82 ± 1.90; hydrofluoric acid 4.54 ± 2.87, and without treatment 2.75 ± 1.49. An increase of 1.94 MPa in shear bond strength was seen in Charisma groups. Silane agent application reduced the Charisma shear bond strength by 0.68 Mpa, but increased Durafill means for bicarbonate blasting (0.83), burs (0.98) and stone drilling (0.46). The sodium bicarbonate blasting, burs and stone drilling methods produced adequate shear bond strength and may be suitable for clinical use. The Charisma micro hybrid resin composite showed higher shear bond means than Durafill micro particle composite.

  17. Risk factors of HIV-1 vertical transmission (VT) and the influence of antiretroviral therapy (ART) in pregnancy outcome.

    Science.gov (United States)

    Barral, Maria F M; de Oliveira, Gisele R; Lobato, Rubens C; Mendoza-Sassi, Raul A; Martínez, Ana M B; Gonçalves, Carla V

    2014-01-01

    In the absence of intervention, the rate of vertical transmission of HIV can range from 15-45%. With the inclusion of antiretroviral drugs during pregnancy and the choice of delivery route this amounts to less than 2%. However ARV use during pregnancy has generated several questions regarding the adverse effects of the gestational and neonatal outcome. This study aims to analyze the risk factors for vertical transmission of HIV-1 seropositive pregnant women living in Rio Grande and the influence of the use of ARVs in pregnancy outcome. Among the 262 pregnant women studied the rate of vertical transmission of HIV was found to be 3.8%. Regarding the VT, there was a lower risk of transmission when antiretroviral drugs were used and prenatal care was conducted at the referral service. However, the use of ART did not influence the outcome of pregnancy. However, initiation of prenatal care after the first trimester had an influence on low birth weight, as well as performance of less than six visits increased the risk of prematurity. Therefore, the risk factors analyzed in this study appear to be related to the realization of inadequate pre-natal and maternal behavior.

  18. RISK FACTORS OF HIV-1 VERTICAL TRANSMISSION (VT AND THE INFLUENCE OF ANTIRETROVIRAL THERAPY (ART IN PREGNANCY OUTCOME

    Directory of Open Access Journals (Sweden)

    Maria F.M. Barral

    2014-04-01

    Full Text Available In the absence of intervention, the rate of vertical transmission of HIV can range from 15-45%. With the inclusion of antiretroviral drugs during pregnancy and the choice of delivery route this amounts to less than 2%. However ARV use during pregnancy has generated several questions regarding the adverse effects of the gestational and neonatal outcome. This study aims to analyze the risk factors for vertical transmission of HIV-1 seropositive pregnant women living in Rio Grande and the influence of the use of ARVs in pregnancy outcome. Among the 262 pregnant women studied the rate of vertical transmission of HIV was found to be 3.8%. Regarding the VT, there was a lower risk of transmission when antiretroviral drugs were used and prenatal care was conducted at the referral service. However, the use of ART did not influence the outcome of pregnancy. However, initiation of prenatal care after the first trimester had an influence on low birth weight, as well as performance of less than six visits increased the risk of prematurity. Therefore, the risk factors analyzed in this study appear to be related to the realization of inadequate pre-natal and maternal behavior.

  19. Analysis of the influences on plumage condition in laying hens: How suitable is a whole body plumage score as an outcome?

    Science.gov (United States)

    Campe, A; Hoes, C; Koesters, S; Froemke, C; Bougeard, S; Staack, M; Bessei, W; Manton, A; Scholz, B; Schrader, L; Thobe, P; Knierim, U

    2018-02-01

    An important indicator of the health and behavior of laying hens is their plumage condition. Various scoring systems are used, and various risk factors for feather damage have been described. Often, a summarized score of different body parts is used to describe the overall condition of the plumage of a bird. However, it has not yet been assessed whether such a whole body plumage score is a suitable outcome variable when analyzing the risk factors for plumage deterioration. Data collected within a German project on farms keeping laying hens in aviaries were analyzed to investigate whether and the extent to which information is lost when summarizing the scores of the separate body parts. Two models were fitted using multiblock redundancy analysis, in which the first model included the whole body score as one outcome variable, while the second model included the scores of the individual body parts as multiple outcome variables. Although basically similar influences could be discovered with both models, the investigation of the individual body parts allowed for consideration of the influences on each body part separately and for the identification of additional influences. Furthermore, ambivalent influences (a factor differently associated with 2 different outcomes) could be detected with this approach, and possible dilutive effects were avoided. We conclude that influences might be underestimated or even missed when modeling their explanatory power for an overall score only. Therefore, multivariate methods that allow for the consideration of individual body parts are an interesting option when investigating influences on plumage condition. © 2017 Poultry Science Association Inc.

  20. Employee customer orientation in context: how the environment moderates the influence of customer orientation on performance outcomes.

    Science.gov (United States)

    Grizzle, Jerry W; Zablah, Alex R; Brown, Tom J; Mowen, John C; Lee, James M

    2009-09-01

    This empirical study evaluated the moderating effects of unit customer orientation (CO) climate and climate strength on the relationship between service workers' level of CO and their performance of customer-oriented behaviors (COBs). In addition, the study examined whether aggregate COB performance influences unit profitability. Building on multisource, multilevel data, the study's results suggest that the influence of employee CO on employee COB performance is positive when the unit's CO climate is relatively high and that the constructs are unrelated when unit CO climate is relatively low. In addition, the data reveal that unit COB performance influences unit profitability by enhancing revenues without a concomitant increase in costs. The study's results underscore the theoretical importance of considering cross-level influencers of employee-level relationships and suggest that managers should focus on creating a climate that is supportive of COBs if their units are to profit from the recruitment, hiring, and retention of customer-oriented employees.

  1. Influence of the Testing Gage Length on the Strength, Young's Modulus and Weibull Modulus of Carbon Fibres and Glass Fibres

    Directory of Open Access Journals (Sweden)

    Luiz Claudio Pardini

    2002-10-01

    Full Text Available Carbon fibres and glass fibres are reinforcements for advanced composites and the fiber strength is the most influential factor on the strength of the composites. They are essentially brittle and fail with very little reduction in cross section. Composites made with these fibres are characterized by a high strength/density ratio and their properties are intrisically related to their microstructure, i.e., amount and orientation of the fibres, surface treatment, among other factors. Processing parameters have an important role in the fibre mechanical behaviour (strength and modulus. Cracks, voids and impurities in the case of glass fibres and fibrillar misalignments in the case of carbon fibres are created during processing. Such inhomogeneities give rise to an appreciable scatter in properties. The most used statistical tool that deals with this characteristic variability in properties is the Weibull distribution. The present work investigates the influence of the testing gage length on the strength, Young's modulus and Weibull modulus of carbon fibres and glass fibres. The Young's modulus is calculated by two methods: (i ASTM D 3379M, and (ii interaction between testing equipment/specimen The first method resulted in a Young modulus of 183 GPa for carbon fibre, and 76 GPa for glass fibre. The second method gave a Young modulus of 250 GPa for carbon fibre and 50 GPa for glass fibre. These differences revelead differences on how the interaction specimen/testing machine can interfere in the Young modulus calculations. Weibull modulus can be a tool to evaluate the fibre's homogeneity in terms of properties and it is a good quality control parameter during processing. In the range of specimen gage length tested the Weibull modulus for carbon fibre is ~ 3.30 and for glass fibres is ~ 5.65, which indicates that for the batch of fibres tested, the glass fibre is more uniform in properties.

  2. 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.

  3. 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)

  4. Influence of Curing Conditions on Long-Term Compressive Strength of Mortars with Accelerating Admixtures

    Science.gov (United States)

    Pizoń, Jan; Łaźniewska-Piekarczyk, Beata

    2017-10-01

    One of disadvantages of accelerating admixtures usage is possibility of significant decline of long-term compressive strength of concrete in comparison to non-modified one. Described tests were intended to define scale of lowered long-term compressive strength of mortars caused by accelerating admixtures in different curing conditions. Portland cement and blended cement with ground granulated blast furnace slag (GGBFS) addition and four types of non-chloride accelerating agents were used. Compressive strength was tested after 7 up to 360 days. Curing conditions were designed to simulate probable conditions close to reality. Such conditions are simulation of internal concrete elements, external elements cast on start of summer and external elements cast on start of winter. Results had shown that it is invalid to state that every accelerating admixture will cause drop of long-term compressive strength in every conditions and for every cement type. Change of curing conditions even after a long time (in this case half of the year) leads to significant differences in compression strength.

  5. А new factor effecting gel strength of pectin polysaccharides

    Directory of Open Access Journals (Sweden)

    S. E. Kholov

    2016-01-01

    Full Text Available Pectin polysaccharides obtained from various raw materials have a different component composition and form gels with water, sugar and acid or calcium. In this study, an experimental approach the gelation properties of different pectin samples, varied from different sources, using new methods of hydrolysis and purification. Samples were obtained by hydrolysis of accelerated extraction of pectin and purified by diaultrfiltration, have a high gel strength. The highest gel strength have been found in series of high methoxyl (HM- pectin samples of apple, peach, orange and low methoxyl (LM- pectin samples of commercial citrus pectin and apple pectin obtained by new method. It is shown that in addition to the basic parameters (the content of galacturonic acid, degree of esterification, molecular weight and hidrodinamic radius macromolecule to affect gel strength pectins aggregation of macromolecules, which is determined by the z-average molecular weight. There were observed a clear pattern of the influence of the molecular weight on hydrodynamic parameters for both HM- and LM- pectin samples on the gel strength. It were shown that a high values of molecular weight, intrinsic viscosity, and radius of gyration of pectin samples can significantly increase gel strength, while the value of Mz oppositely influenced the gel strength. As a result, a systematic analysis of this parameter and its relationship to the average molecular weight found that indeed the ratio Mz/Mw for pectin’s is an crucial to assess the quality of pectin at the study of gel strength for pectin polysaccharides.

  6. Characterizing the influence of stress-induced microcracks on the laboratory strength and fracture development in brittle rocks using a finite-discrete element method-micro discrete fracture network FDEM-μDFN approach

    Directory of Open Access Journals (Sweden)

    Pooya Hamdi

    2015-12-01

    Full Text Available Heterogeneity is an inherent component of rock and may be present in different forms including mineral heterogeneity, geometrical heterogeneity, weak grain boundaries and micro-defects. Microcracks are usually observed in crystalline rocks in two forms: natural and stress-induced; the amount of stress-induced microcracking increases with depth and in-situ stress. Laboratory results indicate that the physical properties of rocks such as strength, deformability, P-wave velocity and permeability are influenced by increase in microcrack intensity. In this study, the finite-discrete element method (FDEM is used to model microcrack heterogeneity by introducing into a model sample sets of microcracks using the proposed micro discrete fracture network (μDFN approach. The characteristics of the microcracks required to create μDFN models are obtained through image analyses of thin sections of Lac du Bonnet granite adopted from published literature. A suite of two-dimensional laboratory tests including uniaxial, triaxial compression and Brazilian tests is simulated and the results are compared with laboratory data. The FDEM-μDFN models indicate that micro-heterogeneity has a profound influence on both the mechanical behavior and resultant fracture pattern. An increase in the microcrack intensity leads to a reduction in the strength of the sample and changes the character of the rock strength envelope. Spalling and axial splitting dominate the failure mode at low confinement while shear failure is the dominant failure mode at high confinement. Numerical results from simulated compression tests show that microcracking reduces the cohesive component of strength alone, and the frictional strength component remains unaffected. Results from simulated Brazilian tests show that the tensile strength is influenced by the presence of microcracks, with a reduction in tensile strength as microcrack intensity increases. The importance of microcrack heterogeneity in

  7. Influence of diesel engine combustion on the rupture strength of partially stabilized zirconia

    International Nuclear Information System (INIS)

    Brinkman, C.R.; Begun, G.M.; Cavin, O.B.; Foster, B.E.; Graves, R.L.; Kahl, W.K.; Liu, K.C.; Simpson, W.A.

    1989-01-01

    Results are reported for tests on partially stabilized zirconia (PSZ-TS and MS grade) bars exposed in the combustion chambers of two operating single-cylinder 0.825-L diesel engines. Specifics of test conditions and procedures are presented. Subsequent to exposure, the bars were subjected to four-point bending and the rupture strengths determined. The TS grade showed a decrease in average strength of 32%, while the strength of the MS grade decreased by about 9% in comparison to average behavior of unaged material. Results of X-ray diffraction analysis, Raman spectroscopy, isothermal aging studies, and ceramographic characterization are given to define reasons for material degradation

  8. The Influence of Wagon Structure Part Shape Optimization on Ultimate Fatigue Strength

    OpenAIRE

    Milovanović, Vladimir; Živković, Miroslav; Jovičić, Gordana; Živković, Jelena; Kozak, Dražan

    2016-01-01

    This study investigates how shape optimisation affects the ultimate fatigue strength of a mechanical part. The mechanical part chosen for this investigation is an axle guard of running gear elements of the Hccrrs 2x2 axle car-carrying wagon. The static and fatigue strength analysis procedure according to the UIC 517 standard and numerical methods have been applied. Material properties were determined experimentally and the necessary numerical calculations were performed by using the finite el...

  9. Reliability and relationships among handgrip strength, leg extensor strength and power, and balance in older men.

    Science.gov (United States)

    Jenkins, Nathaniel D M; Buckner, Samuel L; Bergstrom, Haley C; Cochrane, Kristen C; Goldsmith, Jacob A; Housh, Terry J; Johnson, Glen O; Schmidt, Richard J; Cramer, Joel T

    2014-10-01

    To quantify the reliability of isometric leg extension torque (LEMVC), rate of torque development (LERTD), isometric handgrip force (HGMVC) and RFD (HGRFD), isokinetic leg extension torque and power at 1.05rad·s(-1) and 3.14rad·s(-1); and explore relationships among strength, power, and balance in older men. Sixteen older men completed 3 isometric handgrips, 3 isometric leg extensions, and 3 isokinetic leg extensions at 1.05rad·s(-1) and 3.14rad·s(-1) during two visits. Intraclass correlation coefficients (ICCs), ICC confidence intervals (95% CI), coefficients of variation (CVs), and Pearson correlation coefficients were calculated. LERTD demonstrated no reliability. The CVs for LERTD and HGRFD were ≤23.26%. HGMVC wasn't related to leg extension torque or power, or balance (r=0.14-0.47; p>0.05). However, moderate to strong relationships were found among isokinetic leg extension torque at 1.05rad·s(-1) and 3.14rad·s(-1), leg extension mean power at 1.05rad·s(-1), and functional reach (r=0.51-0.95; p≤0.05). LERTD and HGRFD weren't reliable and shouldn't be used as outcome variables in older men. Handgrip strength may not be an appropriate surrogate for lower body strength, power, or balance. Instead, perhaps handgrip strength should only be used to describe upper body strength or functionality, which may compliment isokinetic assessments of lower body strength, which were reliable and related to balance. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Assessment of maximal handgrip strength : How many attempts are needed?

    NARCIS (Netherlands)

    Reijnierse, Esmee M.; de Jong, Nynke; Trappenburg, Marijke C.; Blauw, Gerard Jan; Butler-Browne, Gillian; Gapeyeva, Helena; Hogrel, Jean Yves; Mcphee, Jamie S.; Narici, Marco V.; Sipilä, Sarianna; Stenroth, Lauri; van Lummel, Rob C.; Pijnappels, Mirjam; Meskers, Carel G M; Maier, Andrea B.

    Background: Handgrip strength (HGS) is used to identify individuals with low muscle strength (dynapenia). The influence of the number of attempts on maximal HGS is not yet known and may differ depending on age and health status. This study aimed to assess how many attempts of HGS are required to

  11. Knee Pain during Strength Training Shortly following Fast-Track Total Knee Arthroplasty: A Cross-Sectional Study

    Science.gov (United States)

    Bandholm, Thomas; Thorborg, Kristian; Lunn, Troels Haxholdt; Kehlet, Henrik; Jakobsen, Thomas Linding

    2014-01-01

    Background Loading and contraction failure (muscular exhaustion) are strength training variables known to influence neural activation of the exercising muscle in healthy subjects, which may help reduce neural inhibition of the quadriceps muscle following total knee arthroplasty (TKA). It is unknown how these exercise variables influence knee pain after TKA. Objective To investigate the effect of loading and contraction failure on knee pain during strength training, shortly following TKA. Design Cross-sectional study. Setting Consecutive sample of patients from the Copenhagen area, Denmark, receiving a TKA, between November 2012 and April 2013. Participants Seventeen patients, no more than 3 weeks after their TKA. Main outcome measures: In a randomized order, the patients performed 1 set of 4 standardized knee extensions, using relative loads of 8, 14, and 20 repetition maximum (RM), and ended with 1 single set to contraction failure (14 RM load). The individual loadings (kilograms) were determined during a familiarization session >72 hours prior. The patients rated their knee pain during each repetition, using a numerical rating scale (0–10). Results Two patients were lost to follow up. Knee pain increased with increasing load (20 RM: 3.1±2.0 points, 14 RM: 3.5±1.8 points, 8 RM: 4.3±2.5 points, P = 0.006), and repetitions to contraction failure (10% failure: 3.2±1.9 points, 100% failure: 5.4±1.6 points, Pknee pain 60 seconds after the final repetition (2.7±2.4 points) was not different from that recorded before strength training (2.7±1.8 points, P = 0.88). Conclusion Both loading and repetitions performed to contraction failure during knee- extension strength-training, increased post-operative knee pain during strength training implemented shortly following TKA. However, only the increase in pain during repetitions to contraction failure exceeded that defined as clinically relevant, and was very short-lived. Trial Registration Clinical

  12. Validating strengths use and deficit correction behaviour scales for South African first-year students

    Directory of Open Access Journals (Sweden)

    Karina Mostert

    2017-01-01

    Research purpose: To examine the validity, measurement invariance and reliability of the proactive strengths use and deficit correction scales for South African first-year university students. Motivation for the study: In order to cope in the demanding university environment, first-year university students need to develop and apply proactive strategies, including using their strengths and developing in their areas of weaknesses. Several studies have indicated that proactive behaviour, specifically strengths use and deficit correction behaviour, lead to favourable outcomes such as higher engagement, lower burnout and more life satisfaction. Therefore, it is important to validate scales that measure these constructs for first-year students. Research design, approach and method: A cross-sectional research approach was used. A sample of South African first-year university students aged between 18 and 23 years (N = 776 was collected. The two scales were tested for their factor structure, measurement invariance, reliability, and convergent and criterion validity. Main findings: A two-factor structure was found for the strengths use and deficit correction behaviour scales. Measurement invariance testing showed that the two scales were interpreted similarly by participants from different campuses and language groups. Cronbach’s alpha coefficients (α ≥ 0.70 indicated that both scales were reliable. In addition, the scales demonstrated convergent validity (comparing them with a general strengths use and proactive behaviour scale. Strengths use and deficit correction behaviour both predicted student burnout, student engagement and life satisfaction, with varying strengths of the relationships for strengths use and deficit correction behaviour. Practical implications: Strengths use and deficit correction behaviour could enable students to manage study demands and enhance well-being. Students will experience favourable outcomes from proactively using strengths and

  13. Influence of personality on the outcome of treatment in depression: systematic review and meta-analysis.

    Science.gov (United States)

    Newton-Howes, Giles; Tyrer, Peter; Johnson, Tony; Mulder, Roger; Kool, Simone; Dekker, Jack; Schoevers, Robert

    2014-08-01

    There continues to be debate about the influence of personality disorder on the outcome of depressive disorders and is relative interactions with treatment. To determine whether personality disorder, both generically and in terms of individual clusters, leads to a worse outcome in patients with depressive disorders and whether this is influenced by type of treatment, a systematic electronic search of MEDLINE, CINAHL, and PsycINFO from 1966, 1982, and 1882, respectively, until February 2007 was undertaken. The keyword terms depression, mental illness, and personality disorder were used. All references were reviewed and personal correspondence was undertaken. Only English language papers were considered. Any English language paper studying a depressed adult population was considered for inclusion. Studies needed to clearly define depression and personality disorder using peer-reviewed instruments or International Classification of Disease/Diagnostic Statistical Manual criteria. Outcome assessment at greater than 3 weeks was necessary. Final inclusion papers were agreed on by consensus by at least two reviewers. All data were extracted using predetermined criteria for depression by at least two reviewers in parallel. Disagreement was settled by consensus. Complex data extraction was confirmed within the study group. Data were synthesized using log odds ratios in the Cochrane RevMan 5 program. The finding of comorbid personality disorder and depression was associated with a more than double the odds of a poor outcome for depression compared with those with no personality disorder (OR 2.16, CI 1.83-2.56). This effect was not ameliorated by the treatment modality used for the depressive disorder. This finding led to the conclusion that personality disorder has a negative impact on the outcome of depression. This finding is important in considering prognosis in depressive disorders.

  14. Antithyroid drugs as a factor influencing the outcome of radioiodine therapy in Graves' disease and toxic nodular goitre?

    Energy Technology Data Exchange (ETDEWEB)

    Koerber, C.; Schneider, P.; Koerber-Hafner, N.; Haenscheid, H.; Reiners, C. [Wuerzburg Univ. (Germany). Abt. fuer Nuklearmedizin

    2001-09-01

    There is controversy over the factors that may influence the outcome of radioiodine therapy for benign thyroid diseases. Antithyroid medication has been claimed to negatively influence the effectiveness of radioiodine therapy in Graves' disease. In a longitudinal study, we assessed the influence of sex, age, antithyroid drugs, target radiation dose, target mass, applied activity, delivered dose, interval between last meal and application, and TSH, FT{sub 3} and FT{sub 4} levels on the outcome of radioiodine therapy. One hundred and forty-four patients (111 female, 33 male) suffering from Graves' disease (GD) and 563 patients (434 female, 129 male) with toxic nodular goitre (TNG) were entered in the study and followed up until 8 months after therapy. Treatment was defined as successful when the TSH level was found to be normal or elevated. Ninety-eight GD patients and 418 TNG patients were successfully treated. Forward stepwise multiple regression analysis models retained only the target mass in GD and the applied activity in TNG as significantly associated with the outcome of therapy. The predictive value of all variables involved was extremely low in both disease groups. Whereas concomitant antithyroid medication had no influence in GD, it adversely influenced radioiodine therapy of TNG. This effect may be attributed to a radioiodine ''steal phenomenon'' induced by TSH-stimulated normal thyroid tissue, which causes overestimation of the uptake in toxic nodules. (orig.)

  15. Dynamic Analysis of the Abnormal Isometric Strength Movement Pattern between Shoulder and Elbow Joint in Patients with Hemiplegia

    Directory of Open Access Journals (Sweden)

    Yali Liu

    2018-01-01

    Full Text Available Patients with hemiplegia usually have weak muscle selectivity and usually perform strength at a secondary joint (secondary strength during performing a strength at one joint (primary strength. The abnormal strength pattern between shoulder and elbow joint has been analyzed by the maximum value while the performing process with strength changing from 0 to maximum then to 0 was a dynamic process. The objective of this study was to develop a method to dynamically analyze the strength changing process. Ten patients were asked to perform four group asks (maximum and 50% maximum voluntary strength in shoulder abduction, shoulder adduction, elbow flexion, and elbow extension. Strength and activities from seven muscles were measured. The changes of secondary strength had significant correlation with those of primary strength in all tasks (R>0.76, p0.4, p<0.01. Deltoid muscles, biceps brachii, triceps brachii, and brachioradialis had significant influences on the abnormal strength pattern (all p<0.01. The dynamic method was proved to be efficient to analyze the different influences of muscles on the abnormal strength pattern. The muscles, deltoid muscles, biceps brachii, triceps brachii, and brachioradialis, much influenced the stereotyped movement pattern between shoulder and elbow joint.

  16. Shear strength and compressibility behaviour of lime-treated organic clay

    OpenAIRE

    Yunus, NZM; Wanatowski, D; Hassan, NA; Marto, A

    2016-01-01

    Apart from strength characteristics, a review of studies on the compressibility of lime-treated soils is equally important that influenced the stability of soil structures. Due to the fact that no study has been carried out, an investigation on the effects of humic acid on strength and compressibility behaviour of lime-stabilised organic clay is presented in this paper. Unconfined Compressive Strength (UCS) and oedometer tests were carried out at different curing periods of 7, 28 and 90 days....

  17. Influence of Nanolime and Curing Period on Unconfined Compressive Strength of Soil

    Directory of Open Access Journals (Sweden)

    Panbarasi Govindasamy

    2017-01-01

    Full Text Available This paper presents the improvement of the unconfined compressive strength (UCS of soil by mixing different percentages of nanolime and 5% lime with soil. The UCS of treated soil increased significantly over curing time with increasing percentage of nanolime. The optimum results were reached at only 0.5% nanolime admixtures which were much higher than 5% lime admixture. This may be due to higher ability of nanolime to flocculate and agglomerate the soil particles compared with the lime. In addition, the lime could fill only the micropores while nanolime could fill the micro- and nanopores as well. The strength gain is inversely proportional to the remolded moisture content and curing period. However, when the content of nanolime used is larger than 0.5%, nanolime particles are not uniformly dispersed. Therefore, a weak area in the form of voids is created, consequently the homogeneous hydrated microstructure cannot be formed, and finally the strength will decrease.

  18. A Holistic Approach to Estimating the Influence of Good Practices on Student Outcomes at Liberal Arts and non-Liberal Arts Institutions

    Directory of Open Access Journals (Sweden)

    Brian P. An

    2016-04-01

    Full Text Available Many higher education administrators and researchers have considered certain “good practices” of institutions as an instrumental way to improve student outcomes. Chickering and Gamson’s (1987 seven principles of good practice has been particularly salient in defining these practices. Often, prior studies only select some of the seven principles for their analysis. Even studies that consider several principles of good practice on student outcomes typically examine the net effect of each principle instead of assessing how these principles holistically influence student outcomes. Using structural equation modeling, we test a basic conceptual framework where we investigate the contribution of the seven principles on a global measure of good practices (GP, as well as the influence of GP on a multitude of student outcomes. We further test whether liberal arts colleges promote an institutional ethos of good practices as compared to non-liberal arts colleges. Overall, the majority (but not all of the principles affect GP. Moreover, we find partial evidence that liberal arts colleges foster an institutional ethos of good practices. Although a commitment to foster good practices may create a supportive environment that influences student outcomes, this commitment may lead to unintended consequences for those with little exposure to these good practices.

  19. Handgrip strength at midlife and familial longevity : The Leiden Longevity Study

    NARCIS (Netherlands)

    Ling, Carolina H.Y.; De Craen, Anton J.M.; Eline Slagboom, P.; Westendorp, Rudi G.J.; Maier, Andrea B.

    2012-01-01

    Low handgrip strength has been linked with premature mortality in diverse samples of middle-aged and elderly subjects. The value of handgrip strength as marker of "exceptional" human longevity has not been previously explored. We postulated that the genetic influence on extreme survival might also

  20. [Evolution in muscle strength in critical patients with invasive mechanical ventilation].

    Science.gov (United States)

    Via Clavero, G; Sanjuán Naváis, M; Menéndez Albuixech, M; Corral Ansa, L; Martínez Estalella, G; Díaz-Prieto-Huidobro, A

    2013-01-01

    To assess the evolution of muscle strength in critically ill patients with mechanical ventilation (MV) from withdrawal of sedatives to hospital discharge. A cohort study was conducted in two intensive care units in the Hospital Universitari de Bellvitge from November 2011 to March 2012. Consecutive patients with MV > 72h. Dependent outcome: Muscle strength measured with the Medical Research Council (MRC) scale beginning on the first day the patient was able to answer 3 out of 5 simple orders (day 1), every week, at ICU discharge and at hospital discharge or at day 60 Independent outcomes: factors associated with muscle strength loss, ventilator-free days, ICU length of stay and hospital length of stay. The patients were distributed into two groups (MRC2 (P 2 and costicosteroids. Patients with a MRC < 48 required more days with MV and a longer ICU stay. Copyright © 2013 Elsevier España, S.L. y SEEIUC. All rights reserved.

  1. Autonomy, Affiliation, and Ability: Relative Salience of Factors that Influence Online Learner Motivation and Learning Outcomes

    Directory of Open Access Journals (Sweden)

    Kuan-Chung Chen

    2010-03-01

    Full Text Available Autonomy, affiliation, and ability appear as main factors that influence online learners‟ motivation and learning outcomes, however, the relative salience of these three factors remains unclear in the online learning literature. Drawing on Deci and Ryan‟s self-determination theory, this study sought to bridge this gap by investigating the relative salience of perceived autonomy, affiliation, and ability on learner motivation and learning outcomes in two special education online programs (N = 262. This study found that the most salient predictor varied from categories of motivation and learning outcomes, and the number of significant predictors increased by participants‟ level of motivation/self-determination. Results of this study provide implications for online learner support.

  2. Shape of Thyroid Cartilage Influences Outcome of Montgomery Medialization Thyroplasty: A Gender Issue.

    Science.gov (United States)

    Desuter, Gauthier; Henrard, Sylvie; Van Lith-Bijl, Julie T; Amory, Avigaëlle; Duprez, Thierry; van Benthem, Peter Paul; Sjögren, Elisabeth

    2017-03-01

    This study aimed to determine whether the shape of the thyroid cartilage and gender influence voice outcomes after a Montgomery thyroplasty implant system (MTIS). A retrospective cohort study was performed on 20 consecutive patients who underwent MTIS. Voice outcome variables were the relative decrease in Voice Handicap Index (%) and the absolute increase in maximum phonation time (MPT) (in seconds). Material variables were the angle between the thyroid cartilage laminae (α-angle), the size of the prosthesis, and a combination of both (the α-ratio). Continuous variables were analyzed using medians and were compared between groups using the Mann-Whitney U test. Factors associated with the outcome variables were assessed by multivariable linear regression. A Pearson coefficient was calculated between material variables. The absolute increase in MPT between the pre- and postoperative period was significantly different between men and women, with a median absolute increase of 11.0 seconds for men and of 1.3 seconds for women (P gender issue that needs to be further studied and eventually tackled. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  3. The influence of the scale effect and high temperatures on the strength and strains of high performance concrete

    Directory of Open Access Journals (Sweden)

    Korsun Vladimyr Ivanovych

    2014-03-01

    Full Text Available The most effective way to reduce the structure mass, labor input and expenses for its construction is to use modern high-performance concrete of the classes С50/60… С90/105, which possess high physical and mathematic characteristics. One of the constraints for their implementation in mass construction in Ukraine is that in design standards there are no experimental data on the physical and mathematic properties of concrete of the classes more than С50/60. Also there are no exact statements on calculating reinforced concrete structures made of high-performance concretes.The authors present the results of experimental research of the scale effect and short-term and long-term heating up to +200 ° C influence on temperature and shrinkage strain, on strength and strain characteristics under compression and tensioning of high-strength modified concrete of class C70/85. The application of high performance concretes is challenging in the process of constructing buildings aimed at operating in high technological temperatures: smoke pipes, coolers, basins, nuclear power plants' protective shells, etc. Reducing cross-sections can lead to reducing temperature drops and thermal stresses in the structures.

  4. Combined effects of petrographic and technological parameters on strength of porous coke substance

    Energy Technology Data Exchange (ETDEWEB)

    Dinel' t, V.M.; Shkoller, M.B.; Stankevich, A.S.; Korchuganova, G.S.

    1983-01-01

    A laboratory study was undertaken to study the combined effects of the basic petrographic characteristics of Kuzbas coal blends and the technological carbonization parameters on the structural strength of the porous coke. Strength tests were carried out on the original coke and the products of partial gasification with carbon dioxide under conditions simulating those inside blast furnaces. Properties of the 14 samples of Kuzbas coals and composition of the four coal blends made from them are listed. It was concluded that the structural strength of coke was most strongly influenced by the average reflectance index and bulk density of the charge. Also, charge compaction can largely offset the adverse influence of petrographic heterogeneity on the strength of the coke. 10 references, 3 tables.

  5. Dynamic plantar pressure distribution, strength capacity and postural control after Lisfranc fracture-dislocation

    DEFF Research Database (Denmark)

    Mehlhorn, Alexander T; Walther, Markus; Yilmaz, Tayfun

    2017-01-01

    of life. 17 consecutive patients suffering from a Lisfranc fracture dislocation were registered, underwent open reduction and internal fixation and were followed-up for 50.5±25.7months (Mean±SDM). Biomechanical analysis of muscle strength capacities, postural control and plantar pressure distribution......Substantial progress has been made in the operative treatment of Lisfranc fractures, however, the prognosis remains poor. We hypothesized that Lisfranc injuries change the postural control and muscle strength of the lower limb. Both are suggested to correlate with the clinical outcome and quality...... correlated well with clinical outcome. Altered postural control was evident by a significant reduction in unilateral stance time, from which we calculated a strong correlation between stance time and the isokinetic strength measurement. Plantar pressure measurements revealed a significant reduction in peak...

  6. Determinants of the Strength of Auditing and Reporting Standards: a Cross-Country Study

    Directory of Open Access Journals (Sweden)

    Pran Krishansing Boolaky

    2013-12-01

    Full Text Available Our study addresses the research gap regarding the absence of an empirical cross-country study on the determinants of the strength of auditing and reporting standards (SARS. Using data on 133 countries at various stages of development, we examine the role of environmental factors that influence a country’s strength of auditing and reporting standards. Our empirical results confirm that institutional infrastructure, financial market development and higher education and training jointly influence a country’s strength of auditing and reporting standards. We obtain qualitatively similar subsample results when we partition countries on the basis of economic development.

  7. Transport and Retention of TiO2 Rutile Nanoparticles in Saturated Porous Media: Influence of Solution pH, Ionic Strength, and the Presence of Humic Acid

    Science.gov (United States)

    The influence of solution pH, ionic strength, and varying concentrations of the Suwannee River Humic Acid (SRHA) on the transport of titanium dioxide (TiO2, rutile) nanoparticle aggregates (nTiO2) in saturated porous media was investigated through systematically examining the tra...

  8. Correcting false information in memory: manipulating the strength of misinformation encoding and its retraction.

    Science.gov (United States)

    Ecker, Ullrich K H; Lewandowsky, Stephan; Swire, Briony; Chang, Darren

    2011-06-01

    Information that is presumed to be true at encoding but later on turns out to be false (i.e., misinformation) often continues to influence memory and reasoning. In the present study, we investigated how the strength of encoding and the strength of a later retraction of the misinformation affect this continued influence effect. Participants read an event report containing misinformation and a subsequent correction. Encoding strength of the misinformation and correction were orthogonally manipulated either via repetition (Experiment 1) or by imposing a cognitive load during reading (Experiment 2). Results suggest that stronger retractions are effective in reducing the continued influence effects associated with strong misinformation encoding, but that even strong retractions fail to eliminate continued influence effects associated with relatively weak encoding. We present a simple computational model based on random sampling that captures this effect pattern, and conclude that the continued influence effect seems to defy most attempts to eliminate it.

  9. A comparative study to determine strength of autopolymerizing acrylic resin and autopolymerizing composite resin influenced by temperature during polymerization: An In Vitro study

    Directory of Open Access Journals (Sweden)

    Anuj Chhabra

    2017-01-01

    Full Text Available Aim: Temporary coverage of a prepared tooth is an important step during various stages of the fixed dental prosthesis. Provisional restorations should satisfy proper mechanical requirements to resist functional and nonfunctional loads. A few studies are carried out regarding the comparison of the effect of curing environment, air and water, on mechanical properties of autopolymerizing acrylic and composite resin. Hence, the aim of this study was to compare the transverse strength of autopolymerizing acrylic resin and autopolymerizing composite resin as influenced by the temperature of air and water during polymerization. Materials and Methods: Samples of autopolymerizing acrylic resin and composite resin were prepared by mixing as per manufacturer's instructions and were placed in a preformed stainless steel mold. The mold containing the material was placed under different controlled conditions of water temperature and air at room temperature. Polymerized samples were then tested for transverse strength using an Instron universal testing machine. Results: Alteration of curing condition during polymerization revealed a significant effect on the transverse strength. The transverse strength of acrylic resin specimens cured at 60°C and composite resin specimens cured at 80°C was highest. Polymerizing the resin in cold water at 10°C reduced the mechanical strength. Conclusions: Polymerization of the resin in hot water greatly increased its mechanical properties. The method of placing resin restoration in hot water during polymerization may be useful for improving the mechanical requirements and obtaining long-lasting performance.

  10. Influence of Internal Sulfate Attack on Some Properties of High Strength Concrete

    Directory of Open Access Journals (Sweden)

    Nada Mahdi Fawzi

    2015-08-01

    Full Text Available One of the most important problems that faces the concrete industry in Iraq is the deterioration due to internal sulfate attack , since it reduces the compressive strength and increases the expansion of concrete. Consequently, the concrete structure may be damage .The effects of total and total effective sulfate contents on high strength concrete (HSC have been studied in the present study. The research studied the effect of sulfate content in cement , sand and gravel , as well as comparing the total sulfate content with the total effective SO3 content. Materials used were divided into two groups of SO3 in cement ,three groups of SO3 in sand ,and two groups of SO3 in gravel. The results show that considering the total effective sulfate content is better than the total content of sulfates since the effect of sulfate in each constituent of concrete, depends on it's granular size .The smaller the particle size of the material the more effective is the sulfate in it. Therefore, it is recommended to follow the Iraqi specification for total effective sulfate content, because it gives more flexibility to the use of sand and gravel with higher sulfate content. The results of compressive strength at 90-days show that the effect of total effective SO3 content of ( 2.647% , 2.992% , 3.424% that correspond to total sulfate of ( 3.778%, 3.294%, 4.528% decrease the compressive strength by (7.53%, 11.44%, 14.59% respectively.

  11. INFLUENCE OF QUARTZ CERAMICS SINGLE-STAGE PROCESSING BY GEL-FORMING WATER SOLUTIONS ON ITS STRENGTH

    Directory of Open Access Journals (Sweden)

    S. K. Evstropiev

    2014-09-01

    Full Text Available The main research results of the influence of quartz ceramics processing by silicon- and aluminum-containing gel- forming water solutions on its durability and porosity are given. Aqueous-alcoholic solutions based on tetraethoxysilane (TEOS, Si(C2H5O4 with additives of aluminum nitrate are proposed for impregnation of porous quartz ceramics samples. Ceramic samples are being impregnated with solutions at the room temperature for 12 minutes. After impregnation they are being exposed to drying at the room temperature for 24 hours and heat treatment in the electric muffle furnace. The made experiments show that impregnation of quartz ceramics porous samples by gel-forming solutions leads to durability growth of not burned samples by 6-7 times even without additional heat treatment. High-temperature heat treatment of previously impregnated ceramic samples leads to decomposition of aluminum nitrate and removal of fossils, and also to hardening of the formed additional bonds between material particles. It considerably improves strength characteristics of quartz ceramics as well. Thus, the possibility of considerable hardening of porous quartz ceramics and stability growth of its strength properties by preliminary impregnation of silicon- and aluminum-bearing gel-forming solutions even without additional heat treatment is experimentally shown. It is revealed that impregnation of porous quartz ceramic samples by these solutions leads only to insignificant reduction of porosity of samples. Subsequent heat treatment of the impregnated porous ceramic samples at the temperatures, equal to 900-1200oC, results in additional significant increase in their mechanical durability.

  12. Improving Strength-Ductility Balance of High Strength Dual-Phase Steels by Addition of Vanadium

    Science.gov (United States)

    Gong, Yu; Hua, M.; Uusitalo, J.; DeArdo, A. J.

    For galvanized or galvannealed steels to be commercially successful, they must exhibit several attributes: (i) easy and inexpensive processing in the hot mill, cold mill and on the coating line, (ii) high strength with good formability and spot weldability, and (iii) good corrosion resistance, especially after cold forming. For good corrosion resistance, the coating must have sufficient coverage, be of uniform thickness, and most importantly, the coating must survive the cold stamping or forming operation. The purpose of this paper is to present research aiming at improving the steel substrate, such that high strength can be obtained while maintaining good global formability (tensile ductility), local formability (sheared-edge ductility), and good spot weldability. It is well-known that the strength of DP steels is controlled by several factors, including the amount of martensite found in the final microstructure. Recent research has revealed that the amount of austenite formed during intercritical annealing can be strongly influenced by the annealing temperature and the pre-annealing conditions of the hot band (coiling temperature) and cold band (% cold reduction). Current experiments have explored the combination of pre-annealing conditions and four annealing practices to help define the best practice to optimize the strength-formability balance in these higher strength DP steels. The steels used in these experiments contained (i) low carbon content for good spot weldability, (ii) the hardenability additions Mo and Cr for strength, and (iii) V for grain refinement, precipitation hardening and temper resistance. When processed correctly, these steels exhibited UTS levels up to 1000MPa, total elongation to 25%, reduction in area to 45%, and Hole Expansion Ratios to 50%. The results of this program will be presented and discussed.

  13. Influence of strength on magnitude and mechanisms of adaptation to power training.

    Science.gov (United States)

    Cormie, Prue; McGuigan, Michael R; Newton, Robert U

    2010-08-01

    To determine whether the magnitude of performance improvements and the mechanisms driving adaptation to ballistic power training differ between strong and weak individuals. Twenty-four men were divided into three groups on the basis of their strength level: stronger (n = 8, one-repetition maximum-to-body mass ratio (1RM/BM) = 1.97 +/- 0.08), weaker (n = 8, 1RM/BM = 1.32 +/- 0.14), or control (n = 8, 1RM/BM = 1.37 +/- 0.13). The stronger and weaker groups trained three times per week for 10 wk. During these sessions, subjects performed maximal-effort jump squats with 0%-30% 1RM. The impact of training on athletic performance was assessed using a 2-d testing battery that involved evaluation of jump and sprint performance as well as measures of the force-velocity relationship, jumping mechanics, muscle architecture, and neural drive. Both experimental groups showed significant (P < or = 0.05) improvements in jump (stronger: peak power = 10.0 +/- 5.2 W.kg, jump height = 0.07 +/- 0.04 m; weaker: peak power = 9.1 +/- 2.3 W.kg, jump height = 0.06 +/- 0.04 m) and sprint performance after training (stronger: 40-m time = -2.2% +/- 2.0%; weaker: 40-m time = -3.6% +/- 2.3%). Effect size analyses revealed a tendency toward practically relevant differences existing between stronger and weaker individuals in the magnitude of improvements in jump performance (effect size: stronger: peak power = 1.55, jump height = 1.46; weaker: peak power = 1.03, jump height = 0.95) and especially after 5 wk of training (effect size: stronger: peak power = 1.60, jump height = 1.59; weaker: peak power = 0.95, jump height = 0.61). The mechanisms driving these improvements included significant (P < or = 0.05) changes in the force-velocity relationship, jump mechanics, and neural activation, with no changes to muscle architecture observed. The magnitude of improvements after ballistic power training was not significantly influenced by strength level. However, the training had a tendency toward

  14. ANALYSING THE PEEL STRENGTH OF FUSIBLE INTERLINING USED IN WOOL FABRIC WITH ELASTANE

    Directory of Open Access Journals (Sweden)

    SARICAM Canan

    2016-05-01

    Full Text Available Fusibles are used to improve the aesthetic and performance characteristics of wool fabrics. The peel strength of fused composites determines the durability of the pressing operation and they are influenced from the process conditions, the characteristics of fusible interlining and the fabric to whom they are sticked to. In this study, it was aimed to analyze the effect of fusible type and process conditions, weave type and different elastane compositions on peel strength. To this aim, two fusible types combined with eight different types of wool fabrics having different amount of elastane were studied. It was found out that only the fusible type and the process conditions are confirmed statistically that they influence the peel strength values. Nonetheless, it was observed as the elastane composition increased, the peel strength values tend to increase for twill type of fabrics and tend to decrease for plain type of fabrics. Moreover, the influence of composition may be in different direction when different type of Fusibles is used to form fusible composites. In conclusion, it can be stated that the dominant mechanism in determination of the peel strength is the selection of fusible type and suitable process conditions for this fusible type and more investigations are necessary if the composition of the material is also influential on the peel strength because of its compatibility with the fusible interlining.

  15. Systematic review: Do patient expectations influence treatment outcomes in total knee and total hip arthroplasty?

    Directory of Open Access Journals (Sweden)

    Haanstra Tsjitske M

    2012-12-01

    Full Text Available Abstract Objective This systematic review aims to summarise all the available evidence related to the association between pre-operative patient expectations (outcome expectations, process expectations and self efficacy expectations and 5 different treatment outcomes (overall improvement, pain, function, stiffness and satisfaction in patients with total knee or total hip arthroplasty at three different follow-op periods (>6 weeks; >6 weeks- ≤6 months; >6 months. Methods English and Dutch language articles were identified through PubMed, EMBASE.com, PsycINFO, CINAHL and The Cochrane Library from inception to September 2012. Articles assessing the association between pre-operative patient expectations and treatment outcomes for TKA/THA in either adjusted or unadjusted analysis were included. Two reviewers, working independently, determined eligibility, rated methodological quality and extracted data on study design, population, expectation measurements, outcome measurements and strength of the associations. Methodological quality was rated by the same reviewers on a 19 item scale. The scores on the quality assessment were taken into account when drawing final conclusions. Results The search strategy generated 2252 unique references, 18 articles met inclusion criteria. Scores on the methodological quality assessment ranged between 6% and 79%. Great variety was seen in definitions and measurement methods of expectations. No significant associations were found between patient expectations and overall improvement, satisfaction and stiffness. Both significant positive and non-significant associations were found for the association between expectations and pain and function. Conclusions There was no consistency in the association between patients’ pre-operative expectations and treatment outcomes for TKA and THA indentified in this systematic review. There exists a need for a sound theoretical framework underlying the construct of

  16. The influence of older age on breast cancer treatment decisions and outcome

    International Nuclear Information System (INIS)

    Merchant, Thomas E.; McCormick, Beryl; Yahalom, Joachim; Borgen, Patrick

    1996-01-01

    Purpose: Information concerning the differences between older and younger women with breast cancer, treated with standard therapy, is lacking from many prospective series. The purpose of this study is to identify factors that influence treatment decisions and determine if women age 65 and older are treated differently than younger women. The outcomes of older women would then be compared to younger women to determine if treatment differences influence outcome. Methods and Materials: The records of 558 women with early invasive breast cancer who were treated with breast conserving surgery and radiation therapy were retrospectively reviewed. Four hundred thirty-two women under the age of 65 (range: 24-64) and 126 women age 65 and older (range: 65-85) were assessed for treatment differences including breast reexcision, extent of axillary dissection, extent of breast and nodal irradiation, and the use of chemotherapy or hormonal therapy. Differences in the treatment of the two groups were determined and the end points of local control, disease-free survival, and overall survival were compared. Median follow-up was 5.5 years. Results: The two treatment groups had identical pathologic TNM staging with the exception that 21% of the older age group and 5% of the younger age group did not undergo axillary dissection. Women age 65 and older were less likely to have a reexcision, extensive axillary dissection, chemotherapy, or nodal irradiation. They were more likely to receive hormonal therapy. Reexcision in older women was positively influenced by a family history of breast cancer and negatively influenced by a history of previous malignancy. None of the patients who were treated without an axillary dissection suffered a regional recurrence. Although local control was better in older patients, there were no differences in disease-free or overall survival for the two groups. Discussion: The findings of this study reveal that older patients have significant treatment

  17. Influence of synthetic calcium silicates on the strength properties of fine-grained concrete

    Science.gov (United States)

    Yarusova, S. B.; Gordienko, P. S.; Kozin, A. V.; Zhevtun, I. G.; Perfilev, A. V.

    2018-04-01

    The effect of additives based on acicular calcium hydrosilicates (xonotlite and tobermorite) and wollastonite, obtained from boric acid production waste in autoclave synthesis at a temperature of 220 °C, on the strength of fine-grained concrete, has been studied in this paper. It was shown that when the calcium hydrosilicates and wollastonite are introduced, an increase in the strength characteristics of concrete is observed. After heat and moisture treatment, the maximum increase in strength is observed with the addition of 4% of mass content of calcium hydrosilicates and 6% of mass content of wollastonite. After 28 days of hardening under normal conditions, the maximum increase in strength of concrete is observed with the addition of 4% of mass content of both types of additives. It was shown that the water absorption of concrete decreases with a maximum when 4% of mass content is added, as in the case of the introduction of calcium hydrosilicates, and wollastonite. With a further increase in the number of additives, the amount of water absorption increases, but these values remain below the values for the control sample without additives.

  18. Influence of gamma-radiation on tensile strength properties of polytetrafluoroethylene (PTFE)

    CERN Document Server

    Gafurov, U G; Nemkova, N

    2002-01-01

    The tensile strength properties of polytetrafluoroethylene are studied at modification doses of gamma-irradiation. The main molecular process of polymer destruction is found to be the thermostimulated slippage of molecular chains. (author)

  19. Does psychotherapy work with school-aged youth? A meta-analytic examination of moderator variables that influence therapeutic outcomes.

    Science.gov (United States)

    Fedewa, Alicia L; Ahn, Soyeon; Reese, Robert J; Suarez, Marietta M; Macquoid, Ahjane; Davis, Matthew C; Prout, H Thompson

    2016-06-01

    The present study is a quantitative synthesis of the available literature to investigate the efficacy of psychotherapy for children's mental health outcomes. In particular, this study focuses on potential moderating variables-study design, treatment, client, and therapist characteristics-that may influence therapeutic outcomes for youth but have not been thoroughly accounted for in prior meta-analytic studies. An electronic search of relevant databases resulted in 190 unpublished and published studies that met criteria for inclusion in the analysis. Effect sizes differed by study design. Pre-post-test designs resulted in absolute magnitudes of treatment effects ranging from |-0.02| to |-0.76| while treatment versus control group comparison designs resulted in absolute magnitudes of treatment effects ranging from |-0.14| to |-2.39|. Changes in youth outcomes larger than 20% were found, irrespective of study design, for outcomes focused on psychosomatization (29% reduction), school attendance (25% increase), and stress (48% reduction). The magnitude of changes after psychotherapy ranged from 6% (externalizing problems) to 48% (stress). Several moderator variables significantly influenced psychotherapy treatment effect sizes, including frequency and length of treatment as well as treatment format. However, results did not support the superiority of a single type of intervention for most outcomes. Implications for therapy with school-aged youth and future research are discussed. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  20. Influence of new societal factors on neovascular age-related macular degeneration outcomes.

    Science.gov (United States)

    Giocanti-Aurégan, Audrey; Chbat, Elige; Darugar, Adil; Morel, Christophe; Morin, Bruno; Conrath, John; Devin, François

    2018-02-01

    To assess the impact of unstudied societal factors for neovascular age-related macular degeneration (nAMD) on functional outcomes after anti-VEGFs. Charts of 94 nAMD patients treated in the Monticelli-Paradis Centre, Marseille, France, were reviewed. Phone interviews were conducted to assess societal factors, including transportation, living status, daily reading and social security scheme (SSS). Primary outcome was the impact of family support and disease burden on functional improvement in nAMD. Between baseline and month 24 (M24), 42.4% of the variability in best-corrected visual acuity (BCVA) was explained by the cumulative effect of the following societal factors: intermittent out-patient follow-up, marital status, daily reading, transportation type, commuting time. No isolated societal factor significantly correlated with ETDRS BCVA severity at M24. A trend to correlation was observed between the EDTRS score at M24 and the SSS (P = 0.076), economic burden (P = 0.075), time between diagnosis and treatment initiation (P = 0.070). A significant correlation was found for the disease burdensome on the patient (P = 0.034) and low vision rehabilitation (P = 0.014). Societal factors could influence functional outcomes in nAMD patients treated with anti-VEGFs. They could contribute to the healing process or sustain disease progression.

  1. Ceramic microsieves: influence of perforation shape and distribution on flow resistance and membrane strength

    NARCIS (Netherlands)

    Kuiper, S.; Brink, R.; Nijdam, W.; Krijnen, Gijsbertus J.M.; Elwenspoek, Michael Curt

    2002-01-01

    Ceramic microsieves with slit-shaped perforations were compared to sieves with circular-shaped perforations, regarding flow resistance and membrane strength. Destructive tests show that the highest strength is obtained if the perforations are placed in a non-alternating pattern. Especially for

  2. 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.

  3. 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

  4. Creep Behavior of High-Strength Concrete Subjected to Elevated Temperatures.

    Science.gov (United States)

    Yoon, Minho; Kim, Gyuyong; Kim, Youngsun; Lee, Taegyu; Choe, Gyeongcheol; Hwang, Euichul; Nam, Jeongsoo

    2017-07-11

    Strain is generated in concrete subjected to elevated temperatures owing to the influence of factors such as thermal expansion and design load. Such strains resulting from elevated temperatures and load can significantly influence the stability of a structure during and after a fire. In addition, the lower the water-to-binder (W-B) ratio and the smaller the quantity of aggregates in high-strength concrete, the more likely it is for unstable strain to occur. Hence, in this study, the compressive strength, elastic modulus, and creep behavior were evaluated at target temperatures of 100, 200, 300, 500, and 800 °C for high-strength concretes with W-B ratios of 30%, 26%, and 23%. The loading conditions were set as non-loading and 0.33f cu . It was found that as the compressive strength of the concrete increased, the mechanical characteristics deteriorated and transient creep increased. Furthermore, when the point at which creep strain occurred at elevated temperatures after the occurrence of transient creep was considered, greater shrinkage strain occurred as the compressive strength of the concrete increased. At a heating temperature of 800 °C, the 80 and 100 MPa test specimens showed creep failure within a shrinkage strain range similar to the strain at the maximum load.

  5. Creep Behavior of High-Strength Concrete Subjected to Elevated Temperatures

    Directory of Open Access Journals (Sweden)

    Minho Yoon

    2017-07-01

    Full Text Available Strain is generated in concrete subjected to elevated temperatures owing to the influence of factors such as thermal expansion and design load. Such strains resulting from elevated temperatures and load can significantly influence the stability of a structure during and after a fire. In addition, the lower the water-to-binder (W–B ratio and the smaller the quantity of aggregates in high-strength concrete, the more likely it is for unstable strain to occur. Hence, in this study, the compressive strength, elastic modulus, and creep behavior were evaluated at target temperatures of 100, 200, 300, 500, and 800 °C for high-strength concretes with W–B ratios of 30%, 26%, and 23%. The loading conditions were set as non-loading and 0.33fcu. It was found that as the compressive strength of the concrete increased, the mechanical characteristics deteriorated and transient creep increased. Furthermore, when the point at which creep strain occurred at elevated temperatures after the occurrence of transient creep was considered, greater shrinkage strain occurred as the compressive strength of the concrete increased. At a heating temperature of 800 °C, the 80 and 100 MPa test specimens showed creep failure within a shrinkage strain range similar to the strain at the maximum load.

  6. Effect of Fluid Dynamic Viscosity on the Strength of Chalk

    DEFF Research Database (Denmark)

    Hedegaard, K.; Fabricius, Ida Lykke

    The mechanical strength of high porosity and weakly cemented chalk is affected by the fluid in the pores. In this study, the effect of the dynamic viscosity of non-polar fluids has been measured on outcrop chalk from Sigerslev Quarry, Stevns, Denmark. The outcome is that the measured strength...... of the chalk decreases with increasing dynamic viscosity. The proposed qualitative explanation is that pressure difference supports and enhances the generation of microscopic shear and tensile failures....

  7. Critical Shoulder Angle and Acromial Index Do Not Influence 24-Month Functional Outcome After Arthroscopic Rotator Cuff Repair.

    Science.gov (United States)

    Lee, Merrill; Chen, Jerry Yongqian; Liow, Ming Han Lincoln; Chong, Hwei Chi; Chang, Paul; Lie, Denny

    2017-11-01

    Recent studies have shown a correlation between scapular geometry and the development of atraumatic rotator cuff tears. However, a paucity of literature is available on the effects of critical shoulder angle (CSA) and acromial index (AI) on functional outcomes after arthroscopic rotator cuff repair. Hypothesis/Purpose: The purpose was to investigate the influence of CSA and AI on 24-month functional outcomes after arthroscopic rotator cuff repair. The hypothesis was that a larger CSA or AI would result in poorer postoperative outcomes. Cohort study; Level of evidence, 3. The study included 147 patients who underwent arthroscopic double-row rotator cuff repair for radiologically documented full-thickness supraspinatus tears. An independent reviewer measured the CSA and AI on preoperative radiographs. These patients were prospectively enrolled and were evaluated preoperatively as well as at 3, 6, 12, and 24 months postoperatively. Functional outcome was assessed with the Constant Shoulder Score (CSS), Oxford Shoulder Score (OSS), and University of California at Los Angeles (UCLA) Shoulder Rating Scale. The patients were first divided based on CSA: (1) ≤35° (control CSA) and (2) >35° (increased CSA); and then based on AI: (1) ≤0.7 and (2) >0.7. The Student unpaired t test, Pearson chi-square test, and Pearson correlation were performed to examine the influence of CSA and AI on postoperative functional outcome scores. At 6 months of follow-up, the CSS, OSS, and UCLA Shoulder Rating Scale were 10 ± 1, 4 ± 2, and 3 ± 1 points poorer in the increased CSA group compared with the control CSA group ( P = .005, P = .030, and P = .035, respectively). These scores were not significantly different between both AI groups. By 24 months of follow-up, all outcome scores were comparable between both CSA groups as well as between both AI groups. No significant correlation was found between either CSA or AI when compared with CSS, OSS, or UCLA Shoulder Rating Scale at 24

  8. Influence of curing regimes on compressive strength of ultra high

    Indian Academy of Sciences (India)

    The present paper is aimed to identify an efficient curing regime for ultra high performance concrete (UHPC), to achieve a target compressive strength more than 150 MPa, using indigenous materials. The thermal regime plays a vital role due to the limited fineness of ingredients and low water/binder ratio. By activation of the ...

  9. Influence of disinfectant solutions on the tensile bond strength of a fourth generation dentin bonding agent

    Directory of Open Access Journals (Sweden)

    BOCANGEL Jorge Saldivar

    2000-01-01

    Full Text Available The purpose of the present study was to evaluate the influence of different disinfectant solutions on the tensile bond strength of a fourth generation dentin bonding agent. Forty non carious human molars were selected. Teeth were embedded in acrylic resin and ground until the exposure of a flat superficial dentin surface. Teeth were randomly divided in 4 groups and treated as follows: Group 1 - 2.5% NaOCl for 40 seconds; Group 2 - 2% chlorhexidine for 40 seconds; Group 3 - 1.23% acidulated fluoride for 4 minutes; and Group 4 - control (without disinfectant solution. Following treatments, Scotchbond Multipurpose Plus® (3M was used according to the manufacturer's instructions. After that, the test specimens were built with composite resin (Z100®-3M, using a standard Teflon matrix. The specimens were stored in distilled water for 24 hours at a temperature of 37ºC. The tensile strength test was performed using a Mini Instrom testing machine. The mean values obtained for each group, in MPa, were: Group 1 - 7.37 (± 2.51; Group 2 - 11.25 (± 4.65; Group 3 - 9.80 (± 3.11; and Group 4 - 10.96 (± 3.37. The results were submitted to statistical analysis using the ANOVA test, and no statistical significant differences among the groups were found. It can be concluded that the different disinfectant substances used in this research do not adversely affect dentin adhesion.

  10. Behaviour and strength assessment of masonry prisms

    Directory of Open Access Journals (Sweden)

    Nassif Nazeer Thaickavil

    2018-06-01

    Full Text Available This is a case study presenting the cracking behavior and assessment of the compressive strength of masonry prisms. The compressive strength of masonry was determined by performing laboratory tests on 192 masonry prism specimens corresponding to 3 specimens each in 64 groups. The variables considered in the experimental program are type of brick, strength of masonry and height-to-thickness (h/t ratio of the prism specimen. Pressed earth bricks and burnt clay bricks were used for the preparation of masonry prisms. A mathematical model is also proposed for the estimation of compressive strength of masonry prisms by performing a statistical multiple regression analysis on 232 data sets, which includes 64 test data from the present study and 168 test data published in the literature. The model was developed based on the regression analysis of test data of prisms made of a variety of masonry units namely clay bricks, pressed earth bricks, concrete blocks, calcium silicate bricks, stone blocks, perforated bricks and soft mud bricks. The proposed model not only accounts for the wide ranges of compressive strengths of masonry unit and mortar, but also accounts for the influence of volume fractions of masonry unit and mortar in addition to the height-to-thickness ratio. The predicted compressive strength of prisms using the proposed model is compared with 14 models available in published literature. The predicted strength was found to be in good agreement with the corresponding experimental data. Keywords: Prism strength, Stack bonded masonry, Running bonded masonry, Masonry unit strength, Cracking

  11. Rheological Properties of Very High-Strength Portland Cement Pastes: Influence of Very Effective Superplasticizers

    Directory of Open Access Journals (Sweden)

    Adriano Papo

    2010-01-01

    Full Text Available The influence of the addition of very effective superplasticizers, that are commercially available, employed for maximising the solid loading of very high-strength Portland cement pastes, has been investigated. Cement pastes were prepared from deionized water and a commercially manufactured Portland cement (Ultracem 52.5 R. Cement and water were mixed with a vane stirrer according to ASTM Standard C305. The 0.38 to 0.44 water/cement ratio range was investigated. Three commercial superplasticizing agents produced by Ruredil S.p.a. were used. They are based on a melamine resin (Fluiment 33 M, on a modified lignosulphonate (Concretan 200 L, and on a modified polyacrylate (Ergomix 1000. Rheological tests were performed at 25°C by using the rate controlled coaxial cylinder viscometer Rotovisko-Haake 20, system M5-osc., measuring device MV2P with serrated surfaces. The tests were carried out under continuous flow conditions. The results of this study were compared with those obtained in a previous article for an ordinary Portland cement paste.

  12. High-strength laser welding of aluminum-lithium scandium-doped alloys

    Science.gov (United States)

    Malikov, A. G.; Ivanova, M. Yu.

    2016-11-01

    The work presents the experimental investigation of laser welding of an aluminum alloy (system Al-Mg-Li) and aluminum alloy (system Al-Cu-Li) doped with Sc. The influence of nano-structuring of the surface layer welded joint by cold plastic deformation on the strength properties of the welded joint is determined. It is founded that, regarding the deformation degree over the thickness, the varying value of the welded joint strength is different for these aluminum alloys. The strength of the plastically deformed welded joint, aluminum alloys of the Al-Mg-Li and Al-Cu-Li systems reached 0.95 and 0.6 of the base alloy strength, respectively.

  13. Does change in isolated lumbar extensor muscle function correlate with good clinical outcome? A secondary analysis of data on change in isolated lumbar extension strength, pain, and disability in chronic low back pain.

    Science.gov (United States)

    Steele, James; Fisher, James; Perrin, Craig; Conway, Rebecca; Bruce-Low, Stewart; Smith, Dave

    2018-01-12

    Secondary analysis of data from studies utilising isolated lumbar extension exercise interventions for correlations among changes in isolated lumbar extension strength, pain, and disability. Studies reporting isolated lumbar extension strength changes were examined for inclusion criteria including: (1) participants with chronic low back pain, (2) intervention ≥ four weeks including isolated lumbar extension exercise, (3) outcome measures including isolated lumbar extension strength, pain (Visual Analogue Scale), and disability (Oswestry Disability Index). Six studies encompassing 281 participants were included. Correlations among change in isolated lumbar extension strength, pain, and disability. Participants were grouped as "met" or "not met" based on minimal clinically important changes and between groups comparisons conducted. Isolated lumbar extension strength and Visual Analogue Scale pooled analysis showed significant weak to moderate correlations (r = -0.391 to -0.539, all p Disability Index pooled analysis showed significant weak correlations (r = -0.349 to -0.470, all p disability, isolated lumbar extension strength changes were greater for those "met" compared with those "not met" (p disability. This study shows significant correlations between increases in isolated lumbar extension strength and reductions in pain and disability. Strengthening of the lumbar extensor musculature could be considered an important target for exercise interventions.

  14. Manual and oral apraxia in acute stroke, frequency and influence on functional outcome: The Copenhagen Stroke Study.

    Science.gov (United States)

    Pedersen, P M; Jørgensen, H S; Kammersgaard, L P; Nakayama, H; Raaschou, H O; Olsen, T S

    2001-09-01

    To determine the frequency of manual and oral apraxia in acute stroke and to examine the influence of these symptoms on functional outcome. Seven hundred seventy six unselected, acute stroke patients who were admitted within seven days of stroke onset with unimpaired consciousness were included. If possible, the patients were assessed for manual and oral apraxia on acute admission. Neurologic stroke severity including aphasia was assessed with the Scandinavian Stroke Scale, and activities of daily living function was assessed with the Barthel Index. All patients completed their rehabilitation in the same large stroke unit. Six hundred eighteen patients could cooperate with the apraxia assessments. Manual apraxia was found in 7% of subjects (10% in left and 4% in right hemispheric stroke; chi2 = 9.0; P = 0.003). Oral apraxia was found in 6% (9% in left and 4% in right hemispheric stroke; chi2 = 5.4; P = 0.02). Both manual and oral apraxia were related to increasing stroke severity, and manual, but not oral, apraxia was associated with increasing age. There was no gender difference in frequency of apraxia. Patients with either type of apraxia had temporal lobe involvement more often than patients without. When analyzed with multiple linear and logistic regression analyses, neither manual nor oral apraxia had any independent influence on functional outcome. Apraxia is significantly less frequent in unselected patients with acute stroke than has previously been assumed and has no independent negative influence on functional outcome.

  15. Personality Strengths as Resilience: A One-Year Multiwave Study.

    Science.gov (United States)

    Goodman, Fallon R; Disabato, David J; Kashdan, Todd B; Machell, Kyla A

    2017-06-01

    We examined how personality strengths prospectively predict reactions to negative life events. Participants were 797 community adults from 42 countries. At five points over the course of 1 year, participants completed a series of questionnaires measuring seven personality strengths (hope, grit, meaning in life, curiosity, gratitude, control beliefs, and use of strengths), subjective well-being, and frequency and severity of negative life events. Using hierarchical linear modeling with assessment periods nested within participants, results from lagged analyses found that only hope emerged as a resilience factor. To illustrate the importance of using appropriate lagged analyses in resilience research, we ran nonlagged analyses; these results suggest that all seven personality strengths moderated the effect of negative life events on subjective well-being, with greater strengths associated with healthier outcomes. To provide evidence that personality strengths confer resilience, a prospective examination is needed with the inclusion of events and responses to them. The use of concurrent methodologies and analyses, which is the norm in psychology, often leads to erroneous conclusions. Hope, the ability to generate routes to reach goals and the motivation to use those routes, was shown to be particularly important in promoting resilience. © 2016 Wiley Periodicals, Inc.

  16. Influence of median surgeon operative duration on adverse outcomes in bariatric surgery.

    Science.gov (United States)

    Reames, Bradley N; Bacal, Daniel; Krell, Robert W; Birkmeyer, John D; Birkmeyer, Nancy J O; Finks, Jonathan F

    2015-01-01

    Evidence suggests that prolonged operative time adversely affects surgical outcomes. However, whether faster surgeons have better outcomes is unclear, as a surgeon׳s speed could reflect skill and efficiency, but may alternatively reflect haste. This study evaluates whether median surgeon operative time is associated with adverse surgical outcomes after laparoscopic Roux-en-Y gastric bypass. We performed a retrospective cohort study using statewide clinical registry data from the years 2006 to 2012. Surgeons were ranked by their median operative time and grouped into terciles. Multivariable logistic regression with robust standard errors was used to evaluate the influence of median surgeon operative time on 30-day surgical outcomes, adjusting for patient and surgeon characteristics, trainee involvement, concurrent procedures, and the complex interaction between these variables. A total of 16,344 patients underwent surgery during the study period. Compared to surgeons in the fastest tercile, slow surgeons required 53 additional minutes to complete a gastric bypass procedure (median [interquartile range] 139 [133-150] versus 86 [69-91], Ppatient characteristic only, slow surgeons had significantly higher adjusted rates of any complication, prolonged length of stay, emergency department visits or readmissions, and venous thromboembolism (VTE). After further adjustment for surgeon characteristics, resident involvement, and the interaction between these variables, slow surgeons had higher rates of any complication (10.5% versus 7.1%, P=.039), prolonged length of stay (14.0% versus 4.4%, P=.002), and VTE (0.39% versus .22%, P<.001). Median surgeon operative duration is independently associated with adjusted rates of certain adverse outcomes after laparoscopic Roux-en-Y gastric bypass. Improving surgeon efficiency while operating may reduce operative time and improve the safety of bariatric surgery. Copyright © 2015 American Society for Bariatric Surgery. Published by

  17. [Influence of Attachment Style on the Outcome of Bariatric Surgery - A Pilot Study].

    Science.gov (United States)

    Appel, Johanna Elisabeth; Ift, Franziska; Kißler, Hermann; Kloos, Christof; Lehmann, Thomas; Strauß, Bernhard; Wick, Katharina

    2016-12-01

    Background: Bariatric surgery can lower body weight and comorbidities. Different factors might influence the outcome of this treatment. This pilot study examines whether patients' attachment style can influence surgical outcome. Methods: The sample consisted of 32 patients (f=24; m=8; BMI preoperative=47,8 kg/m 2 ±5,2; age=53±9,84) who underwent a laparoscopic sleeve gastrectomy. The following variables were assessed pre- and postoperatively via questionnaires: quality of life (BAROS), self esteem (SES), depression, anxiety, psychological distress (SCL-90R), feelings of hunger, cognitive control, irritated eating behaviour (FEV) and weight related variables (BMI, EWL%, EBL%, TBL). Attachment style was determined postoperatively using the BPQE. Results: None of the participating patients suffered from a binge eating disorder. There was no significant difference of the BMI at any time between the 12 securely attached (SA) patients and the 19 insecurely attachted (IA) patients. Compared to the SA patients IA patients preoperatively showed lower outcomes in variables concerning eating behaviour and mental health. Comparing the 2 groups postoperatively the IA patients achieved lower levels in variables concerning mental health than SA patients and did not reach the preoperative values of the SA patients. Both groups benefited from surgery related to weight loss, mental health and eating behaviour. There was no difference found in the development from pre- to postoperative between SA and IA patients. Discussion & Conclusion: Patients profit by a bariatric intervention independent of their attachment style. By evaluating the attachment style, it could be possible to individually optimize pre- and postoperative patients support in order to gain more effective surgery results. Follow up studies extended to multi-site assessment are required. © Georg Thieme Verlag KG Stuttgart · New York.

  18. The Influence of Trainee Gaming Experience and Computer Self-Efficacy on Learner Outcomes of Videogame-Based Learning Environments

    National Research Council Canada - National Science Library

    Orvis, Karin A; Orvis, Kara L; Belanich, James; Mullin, Laura N

    2005-01-01

    .... The purpose of the current research was to investigate the influence of two trainee characteristics, prior videogame experience and computer self-efficacy, on learner outcomes of a videogame-based training environment...

  19. High-strength structural steels; their properties, and the problems encountered during the welding process

    International Nuclear Information System (INIS)

    Uwer, D.

    1978-01-01

    High-strength structural steels, manufacture, properties. Requirements to be met by the welded joints of high-strength structural steels. Influence of the welding conditions on the mechanical properties in the heat-affected zone. Cold-cracking behaviour of welded joints. Economic efficiency of high-strength structural steels. Applications. (orig.) [de

  20. Does Parental Mediation of Media Influence Child Outcomes? A Meta-Analysis on Media Time, Aggression, Substance Use, and Sexual Behavior

    Science.gov (United States)

    Collier, Kevin M.; Coyne, Sarah M.; Rasmussen, Eric E.; Hawkins, Alan J.; Padilla-Walker, Laura M.; Erickson, Sage E.; Memmott-Elison, Madison K.

    2016-01-01

    The current study examined how parental mediation of media (restrictive mediation, active mediation, and coviewing) influenced child outcomes. Three meta-analyses, 1 for each type of mediation, were conducted on a total of 57 studies. Each analysis assessed the effectiveness of parental mediation on 4 pertinent child outcomes: media use,…

  1. Influence of Using Clinical Microscope as Auxiliary to Perform Mechanical Cleaning of Post Space: A Bond Strength Analysis.

    Science.gov (United States)

    Ferreira, Ricardo; Prado, Maíra; de Jesus Soares, Adriana; Zaia, Alexandre Augusto; de Souza-Filho, Francisco José

    2015-08-01

    The aim of the present study was to evaluate the influence of using a clinical microscope while performing mechanical cleaning of post space walls on the bond strength of a fiberglass post to dentin. Forty-five bovine roots were used. After preparation, roots were filled using gutta-percha and Pulp Canal Sealer (SybronEndo, Orange, CA). Subsequently, for post space preparation, the roots were divided into 3 groups: control (only heat condenser + specific bur of the post system); cleaning without a microscope, mechanical cleaning (after the procedure described in the control group, round burs were used to improve cleaning); and cleaning with a microscope, mechanical cleaning performed with round burs visualized under a clinical microscope. Then, fiberglass posts were cemented. The roots were prepared and evaluated by the push-out test. Data were analyzed using Kruskal-Wallis and Student-Newman-Keuls tests (P microscope (cervical 1.66 ± 2.3, middle 0.65 ± 1.1, apical 0.79 ± 1.2, and total1.04 ± 1.7), and cleaning with a microscope (cervical 3.26 ± 2.8, middle 1.97 ± 3.5, apical 1.85 ± 4.1, and total 2.37 ± 3.5). In the cleaning with a microscope group, the bond strength values were significantly higher than those in the other groups. In all groups, the main failure pattern was adhesive between cement and dentin. The use of a clinical microscope while performing mechanical cleaning during post space preparation improved the bond strength of a fiberglass post to dentin. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. The Use Level of Chrome Tannage For Rabbit Fur Leather Observed on Tearing Strength, Stitch Tearing Strength, Water Absorption and Organoleptic

    Directory of Open Access Journals (Sweden)

    Mustakim Mustakim

    2012-02-01

    Full Text Available The purpose of this study was to find out the appropiate of chrome tannage level for rabbit fur leather quality. The result were expected to contribute information for many people who relate with tanning technology, especialy about the use level of chrome tannage for fur leather quality and could as patern to hold further research.The material that used were 12 pieces of three months of rabbit skin. The method is Completely Randomized Design, consist of three treatments of chrome tannage (Chromosal B, they were : B1 (Chromosal B 6%, B2 (Chromosal B 8%, and B3 (Chromosal B 10%. Each of treatment hold on four replications. The variables which measured are tearing strength, stitch teraing strength, water absorption and organoleptic consist of “kekuatan bulu”’ “kerataan bulu” and “kelemasan kulit” in fur leather. Data was analysed by analysis variance followed by Duncan’s Multiple Range Test. The result of this research show that the use level of chromosal B give very significant influence among tearing strength, stitch tearing strength and water absorption. It gave significant influence among the organoleptic test. Based on the result, can be concluded that 10 percent of chrome tannage (chromosal B, produce the best result on tearing strength, stitch tearing strength, water absorption and organoleptic for “kekuatan bulu” and “kerataan bulu”. The incrase of chrome tannage offer will decrease the “kelemasan kulit” in fur leather and the best “kelemasan kulit” produced by the lowest chrome tannage offer, that was 6 percent of Chromosal B. The best quality of rabbit fur leather produced by 10 percent of chrome tannage offer.   Keywords: chrome, tannage, fur leather

  3. How the Subpolar gyre strength influences phytoplankton blooms dynamics in the North Atlantic

    DEFF Research Database (Denmark)

    Ferreira, Ana Sofia; Payne, Mark; MacKenzie, Brian

    2012-01-01

    height (SSH, from the AVISO project) as a proxy of current strength. Three regions were strategically chosen to characterize positions relative to the NASPG, describing: region 1—the northern part of NASPG, including the Irminger Current (IC); region 2—the North Atlantic Current (NAC), its northwards......Changes in the North Atlantic Subpolar gyre (NASPG) have been linked to the interannual variability of primary production. However, little is known about the mechanisms behind both environmental processes, and how the NASPG strength may extend its potential impacts to higher trophic levels......, including early life stages of commercial fish species. We assess NASPG strength effect on North Atlantic phytoplankton bloom dynamics. We analyse time‐series (from 1998 to 2010) of chlorophyll a (Chl a, from the Globcolour project) annual anomaly as a proxy of phytoplankton abundance, and of sea surface...

  4. Knee Pain during Strength Training Shortly following Fast-Track Total Knee Arthroplasty

    DEFF Research Database (Denmark)

    Bandholm, Thomas; Thorborg, Kristian; Lunn, Troels Haxholdt

    2014-01-01

    BACKGROUND: Loading and contraction failure (muscular exhaustion) are strength training variables known to influence neural activation of the exercising muscle in healthy subjects, which may help reduce neural inhibition of the quadriceps muscle following total knee arthroplasty (TKA). It is unkn......BACKGROUND: Loading and contraction failure (muscular exhaustion) are strength training variables known to influence neural activation of the exercising muscle in healthy subjects, which may help reduce neural inhibition of the quadriceps muscle following total knee arthroplasty (TKA......). It is unknown how these exercise variables influence knee pain after TKA. OBJECTIVE: To investigate the effect of loading and contraction failure on knee pain during strength training, shortly following TKA. DESIGN: Cross-sectional study. SETTING: Consecutive sample of patients from the Copenhagen area, Denmark...... TKA. However, only the increase in pain during repetitions to contraction failure exceeded that defined as clinically relevant, and was very short-lived. TRIAL REGISTRATION: ClinicalTrials.gov NCT01729520....

  5. Expectancies, working alliance, and outcome in transdiagnostic and single diagnosis treatment for anxiety disorders: An investigation of mediation.

    Science.gov (United States)

    Sauer-Zavala, Shannon; Boswell, James F; Bentley, Kate H; Thompson-Hollands, Johanna; Farchione, Todd J; Barlow, David H

    2018-04-01

    Patients' outcome expectancies and the working alliance are two psychotherapy process variables that researchers have found to be associated with treatment outcome, irrespective of treatment approach and problem area. Despite this, little is known about the mechanisms accounting for this association, and whether contextual factors (e.g., psychotherapy type) impact the strength of these relationships. The primary aim of this study was to examine whether patient-rated working alliance quality mediates the relationship between outcome expectancies and pre- to post-treatment change in anxiety symptoms using data from a recent randomized clinical trial comparing a transdiagnostic treatment (the Unified Protocol [UP]; Barlow et al., 2011a; Barlow, Sauer-Zavala, et al., in press) to single diagnosis protocols (SDPs) for patients with a principal heterogeneous anxiety disorder ( n = 179). The second aim was to explore whether cognitive-behavioral treatment condition (UP versus SDP) moderated this indirect relationship. Results from mediation and moderated mediation models indicated that, when collapsing across the two treatment conditions, the relationship between expectancies and outcome was partially mediated by the working alliance ( B = .037, SE = .05, 95% CI [.005, .096]). Interestingly, within-condition analyses showed that this conditional indirect effect was only present for SDP patients, whereas in the UP condition, working alliance did not account for the association between expectancies and outcome. These findings suggest that outcome expectancies and working alliance quality may interact to influence treatment outcomes, and that the nature and strength of the relationships among these constructs may differ as a function of the specific cognitive-behavioral treatment approach utilized.

  6. Outcomes of a Character Strengths-Based Intervention on Self-Esteem and Self-Efficacy of Psychiatrically Hospitalized Youths.

    Science.gov (United States)

    Toback, Rebecca L; Graham-Bermann, Sandra A; Patel, Paresh D

    2016-05-01

    Mental health treatment approaches based on character strengths can be used to complement the traditional focus on functional impairment. The study tested use of a character strengths-based intervention to enhance the self-esteem and self-efficacy of psychiatrically hospitalized youths. Eighty-one hospitalized adolescents were randomly assigned to intervention or comparison groups. The intervention used the Values in Action Inventory of Strengths for Youth to discover character strengths and incorporate them into coping skills. Self-efficacy and self-esteem were measured at baseline, postintervention, two weeks, and three months. Self-esteem and self-efficacy initially increased in both groups, but only the intervention group showed sustained improvement. The intervention was associated with increased self-efficacy at two weeks and increased self-efficacy and self-esteem at three months. A brief, easily administered character strengths-based intervention may be an adjunctive tool in the treatment of psychiatrically hospitalized youths.

  7. Influence of application method on surface free-energy and bond strength of universal adhesive systems to enamel.

    Science.gov (United States)

    Imai, Arisa; Takamizawa, Toshiki; Sai, Keiichi; Tsujimoto, Akimasa; Nojiri, Kie; Endo, Hajime; Barkmeier, Wayne W; Latta, Mark A; Miyazaki, Masashi

    2017-10-01

    The aim of the present study was to determine the influence of different adhesive application methods and etching modes on enamel bond effectiveness of universal adhesives using shear bond strength (SBS) testing and surface free-energy (SFE) measurements. The adhesives Scotchbond Universal, All-Bond Universal, Adhese Universal, and G-Premio Bond were used. Prepared bovine enamel specimens were divided into four groups, based on type of adhesive, and subjected to the following surface treatments: (i) total-etch mode with active application; (ii) total-etch mode with inactive application; (iii) self-etch mode with active application; and (iv) self-etch mode with inactive application. Bonded specimens were subjected to SBS testing. The SFE of the enamel surfaces with adhesive was measured after rinsing with acetone and water. The SBS values in total-etch mode were significantly higher than those in self-etch mode. In total-etch mode, significantly lower SBS values were observed with active application compared with inactive application; in contrast, in self-etch mode there were no significant differences in SBS between active and inactive applications. A reduction in total SFE was observed for active application compared with inactive application. The interaction between etching mode and application method was statistically significant, and the application method significantly affected enamel bond strength in total-etch mode. © 2017 Eur J Oral Sci.

  8. In-vitro orthodontic bond strength testing : A systematic review and meta-analysis

    NARCIS (Netherlands)

    Finnema, K.J.; Ozcan, M.; Post, W.J.; Ren, Y.J.; Dijkstra, P.U.

    INTRODUCTION: The aims of this study were to systematically review the available literature regarding in-vitro orthodontic shear bond strength testing and to analyze the influence of test conditions on bond strength. METHODS: Our data sources were Embase and Medline. Relevant studies were selected

  9. Evaluation of strength-controlling defects in paper by stress concentration analyses

    Science.gov (United States)

    John M. Considine; David W. Vahey; James W. Evans; Kevin T. Turner; Robert E. Rowlands

    2011-01-01

    Cellulosic webs, such as paper materials, are composed of an interwoven, bonded network of cellulose fibers. Strength-controlling parameters in these webs are influenced by constituent fibers and method of processing and manufacture. Instead of estimating the effect on tensile strength of each processing/manufacturing variable, this study modifies and compares the...

  10. The Influence of Posttraumatic Stress Disorder on Treatment Outcomes of Patients With Borderline Personality Disorder.

    Science.gov (United States)

    Boritz, Tali; Barnhart, Ryan; McMain, Shelley F

    2016-06-01

    The aim of this study was to determine the influence of posttraumatic stress disorder (PTSD) on treatment outcomes in patients with borderline personality disorder (BPD). Participants were 180 individuals diagnosed with BPD enrolled in a randomized controlled trial that compared the clinical and cost effectiveness of dialectical behavior therapy (DBT) and general psychiatric management (GPM). Multilevel linear models and generalized linear models were used to compare clinical outcomes of BPD patients with and without PTSD. BPD patients with comorbid PTSD reported significantly higher levels of global psychological distress at baseline and end of treatment compared to their non-PTSD counterparts. Both groups evidenced comparable rates of change on suicide attempts and non-suicidal self-injury (NSSI), global psychological distress, and BPD symptoms over the course of treatment and post-treatment follow-up. DBT and GPM were effective for BPD patients with and without PTSD across a broad range of outcomes.

  11. Influence of matrix metalloproteinase synthetic inhibitors on dentin microtensile bond strength of resin cements.

    Science.gov (United States)

    Stape, T H S; Menezes, M S; Barreto, B C F; Aguiar, F H B; Martins, L R; Quagliatto, P S

    2012-01-01

    This study evaluated the effect of dentin pretreatment with 2% chlorhexidine (CHX) or 24% ethylenediamine tetra-acetic acid gel (EDTA) on the dentin microtensile bond strength (μTBS) of resin cements. Composite blocks were luted to superficial noncarious human dentin (n=10) using two resin cements (RelyX ARC [ARC] and RelyX U100 [U100]) and three dentin pretreatments (without pretreatment-control, CHX, and EDTA). CHX was applied for 60 seconds on the acid-etched dentin in the ARC/CHX group, and for the same time on smear layer-covered dentin in the U100/CHX group. EDTA was applied for 45 seconds on smear-covered dentin in the U100/EDTA group, and it replaced phosphoric acid conditioning in the ARC/EDTA group for 60 seconds. After storage in water for 24 hours, specimens were prepared for microtensile bond strength testing. The results were submitted to two-way analysis of variance (ANOVA) followed by Tukey test. ARC produced significantly higher μTBS (pEDTA was used. For ARC, no pretreatment and CHX produced higher μTBS than EDTA. For U100, EDTA produced higher μTBS; no statistical difference occurred between CHX pretreatment and when no pretreatment was performed. While CHX did not affect immediate dentin bond strength of both cements, EDTA improved bond strength of U100, but it reduced dentin bond strength of ARC.

  12. Influence of surface treatments on the shear bond strength of orthodontic brackets to porcelain

    Science.gov (United States)

    Wang, Cong; Zeng, Jishan; Wang, Shaoan; Yang, Zheng; Huang, Qian; Chen, Pixiu; Zhou, Shujuan; Liu, Xiaoqing

    2008-11-01

    The purpose of this study was to investigate the effect of various surface treatments after different storage time and thermocycling on the shear bond strength of orthodontic brackets to the feldspathic porcelain surfaces. 128 disc-shaped porcelain specimens were randomly assigned to the following surface treatments: 9.6% HFA, 9.6% HFA combined with silane, 50 μ aluminum trioxide sandblasting followed by silane and application of silane after 37% phosphoric acid. Metal or ceramic brackets were bonded onto each treated porcelain facet with light cured resin. The samples were stored in 37 °C water 1 day or 7 days, thermocycled 500 times from 5 to 55 °C. The shear bond strengths were measured (1 mm/min), and statistically analyzed. The bond failure sites were classified according to ARI system. The surface of the glazed, sandblasted, hydrofluoric and phosphoric acid etched porcelain were examined with SEM. All groups achieved reasonable bond strengths to withstand the application of orthodontic forces. Water storage for 7 days caused lower shear bond strength than that of 1 day. But there is no statistically significant difference between the two groups. The mean shear bond strength provided by ceramic bracket with mechanical retention had no statistical difference with that of metal bracket. Therefore, the optimal treatment for orthodontic brackets bonding to feldspathic porcelain was to apply phosphoric acid combined with silane.

  13. The influence of attention biases and adult attachment style on treatment outcome for adults with social anxiety disorder.

    Science.gov (United States)

    Byrow, Yulisha; Peters, Lorna

    2017-08-01

    Attention biases figure prominently in CBT models of social anxiety and are thought to maintain symptoms of social anxiety disorder (SAD). Studies have shown that individual differences in pre-treatment attention biases predict cognitive behavioural therapy (CBT) outcome. However, these findings have been inconsistent as to whether vigilance towards threat predicts better or poorer treatment outcome. Adult attachment style is an individual characteristic that may influence the relationship between attention bias and SAD. This study investigates the relationship between attention biases and CBT treatment outcome for SAD. Furthermore, we examined the influence of adult attachment style on this relationship. Participants with a primary diagnosis of SAD completed a passive viewing (measuring vigilance towards threat) and a novel difficulty to disengage (measuring difficulty to disengage attention) eye-tracking task prior to attending 12 CBT group sessions targeting SAD. Symptom severity was measured at pre- and post-treatment. Regression analyses were conducted on a sample of 50 participants. Greater vigilance for threat than avoidance of threat at pre-treatment predicted poorer treatment outcomes. Greater difficulty disengaging from happy faces, compared to neutral faces, predicted poorer treatment outcomes. Attachment style did not moderate these relationships. The associations between attention biases and specific components of CBT treatment were not examined. The novel findings regarding difficulty to disengage attention require replication. The findings have implications for the theoretical models of SAD and for the treatment of SAD. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Effect of laser welding on the titanium ceramic tensile bond strength

    Directory of Open Access Journals (Sweden)

    Rodrigo Galo

    2011-08-01

    Full Text Available Titanium reacts strongly with elements, mainly oxygen at high temperature. The high temperature of titanium laser welding modifies the surface, and may interfere on the metal-ceramic tensile bond strength. OBJECTIVE: The influence of laser welding on the titanium-ceramic bonding has not yet been established. The purpose of this in vitro study was to analyze the influence of laser welding applied to commercially pure titanium (CpTi substructure on the bond strength of commercial ceramic. The influence of airborne particle abrasion (Al2O3 conditions was also studied. MATERIAL AND METHODS: Forty CpTi cylindrical rods (3 mm x 60 mm were cast and divided into 2 groups: with laser welding (L and without laser welding (WL. Each group was divided in 4 subgroups, according to the size of the particles used in airborne particle abrasion: A - Al2O3 (250 µm; B - Al2O3 (180 µm; C - Al2O3 (110 µm; D - Al2O3 (50 µm. Ceramic rings were fused around the CpTi rods. Specimens were invested and their tensile strength was measured at fracture with a universal testing machine at a crosshead speed of 2.0 mm/min and 200 kgf load cell. Statistical analysis was carried out with analysis of variance and compared using the independent t test (p<0.05. RESULTS: Significant differences were found among all subgroups (p<0.05. The highest and the lowest bond strength means were recorded in subgroups WLC (52.62 MPa and LD (24.02 MPa, respectively. CONCLUSION: Airborne particle abrasion yielded significantly lower bond strength as the Al2O3 particle size decreased. Mechanical retention decreased in the laser-welded specimens, i.e. the metal-ceramic tensile bond strength was lower.

  15. Influence of corneal asphericity on the refractive outcome of intraocular lens implantation in cataract surgery.

    Science.gov (United States)

    Savini, Giacomo; Hoffer, Kenneth J; Barboni, Piero

    2015-04-01

    To evaluate the possible influence of anterior corneal surface asphericity on the refractive outcomes in eyes having intraocular lens (IOL) implantation after cataract surgery. Fondazione G.B. Bietti IRCCS, Rome, Italy. Retrospective comparative case series. Intraocular lens power was calculated using the Haigis, Hoffer Q, Holladay 1, and SRK/T formulas. Asphericity (Q-value) was measured at 8.0 mm with a Placido-disk corneal topographer (Keratron), a rotating Scheimpflug camera (Pentacam), and a rotating Scheimpflug camera combined with Placido-disk corneal topography (Sirius). The relationship between the error in refraction prediction (ie, difference between expected refraction and refraction measured 1 month after surgery) and the Q-value was assessed by linear regression. The same IOL model (Acrysof SA60AT) was implanted in 115 eyes of 115 consecutive patients. Regression analysis showed a statistically significant relationship between the error in refraction prediction and the Q-value with all formulas and all devices. In all cases, a more negative Q-value (prolate cornea) was associated with a myopic outcome, whereas a more positive Q-value (oblate cornea) was associated with a hyperopic outcome. The highest coefficient of determination was detected between the Hoffer Q formula and the Placido-disk corneal topographer (R(2) = 0.2630), for which the error in refraction prediction (y) was related to the Q-value (x) according to the formula y = -0.2641 + 1.4589 × x. Corneal asphericity influences the refractive outcomes of IOL implantation and should be taken into consideration when using third-generation IOL power formulas. Dr. Hoffer receives book royalties from Slack, Inc., Thorofare, New Jersey, and formula royalties from all manufacturers using the Hoffer Q formula. No other author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  16. Influence of body habitus on feasibility and outcome of laparoscopic liver resections: a prospective study.

    Science.gov (United States)

    Ratti, Francesca; D'Alessandro, Valentina; Cipriani, Federica; Giannone, Fabio; Catena, Marco; Aldrighetti, Luca

    2016-06-01

    The aim of the present study was to prospectively investigate whether the anthropometric measures of A Body Shape Index (ABSI, taking into account waist circumference adjusted for height and weight) affects feasibility and outcome of laparoscopic liver resections. One hundred patients undergoing laparoscopic liver resection were prospectively included in the study (2014-2015). Preoperative clinical parameters, including body mass index (BMI) and ABSI were evaluated for associations with intraoperative outcome and postoperative results (morbidity, mortality and functional recovery). Twenty-two and 78 patients underwent major and minor hepatectomies, respectively. Conversion rate was 9%, mean blood loss was 210 ± 115 ml. Postoperative morbidity was 15% and mortality was nil. Mean length of stay was 4 days. When considering the entire series, ABSI was not associated with intra and postoperative outcome. After stratification of patients according to difficulty score, Pearson's correlation demonstrated an association between ABSI and intraoperative blood loss (P = 0.03) and time for functional recovery (P = 0.05) in patients undergoing resections with high score of difficulty. Body habitus has an influence on outcome of laparoscopic liver resections with high degree of difficulty, while feasibility and outcome of low difficulty resections seem not to be affected by anthropometric measures. © 2016 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  17. Influence of arterial occlusion on outcome after intravenous thrombolysis for acute ischemic stroke.

    Science.gov (United States)

    Medlin, Friedrich; Amiguet, Michael; Vanacker, Peter; Michel, Patrik

    2015-01-01

    We aimed to assess the interaction between intravenous thrombolysis (IVT) and arterial occlusion on acute cervicocerebral computed tomographic angiography on the outcome of patients with acute ischemic stroke. Patients from the Acute Stroke Registry and Analysis of Lausanne (ASTRAL) registry with onset-to-door-time ≤4 hours, acute cervicocerebral computed tomographic angiography, a premorbid modified Rankin Scale ≤2, and a National Institute of Health Stroke Scale (NIHSS) >4 were selected. Patients with significant intracranial arterial obstruction (≥50%-99%) and undergoing acute endovascular treatment were excluded. An interaction analysis of IVT and initial arterial occlusion for favorable 3 months outcome (modified Rankin Scale <3) were performed with adjustment for potential confounders. Among 654 included patients, 382 (58%) showed arterial occlusion, of whom 263 (69%) received IVT. Two hundred seventy-two showed no/minimal obstruction of whom 139 (51%) received IVT. In the adjusted interaction analysis, there was a trend in favor of the arterial occlusion group (odds ratio [OR]=3.97; 95% confidence interval [CI], 0.83-18.97; P=0.08). IVT (versus no IVT) was associated with better outcome in patients with occlusion (adjusted OR for favorable outcome, 3.01; 95% CI, 1.10-8.28) but not in patients with no/minimal obstruction (OR, 0.76; 95% CI, 0.21-2.74). Conversely, patients with occlusion had a similar rate of favorable outcome as no/minimal obstruction when thrombolysed (OR, 0.5; 95% CI, 0.17-1.47) but had a less favorable outcome without thrombolysis (OR, 0.13; 95% CI, 0.04-0.44). In this retrospective analysis of consecutive patients with acute ischemic stroke, there was a trend for more favorable outcomes with IVT in the setting of initial arterial occlusion than in the setting of no/minimal obstruction. Before confirmation in randomized controlled studies, this information should not influence thrombolysis decisions, however. © 2014 American Heart

  18. influence of orientation and size of voids on concrete cube strength

    African Journals Online (AJOL)

    Dr Obe

    (1982),"Structural Masonry Designer's. Manual", Granada Publishing Frogmore,. G.B.. 9. Ezeokonkwo, J.C (1988), "Uniaxial. Compressive Strength of Sandcrete. Hollow Blocks and its Dependence on. Geometry", M. Eng. Thesis, submitted to the Department of Civil Engineering,. University of Nigeria, Nsukka, Nigeria. 10.

  19. Strength evaluation code STEP for brittle materials

    International Nuclear Information System (INIS)

    Ishihara, Masahiro; Futakawa, Masatoshi.

    1997-12-01

    In a structural design using brittle materials such as graphite and/or ceramics it is necessary to evaluate the strength of component under complex stress condition. The strength of ceramic materials is said to be influenced by the stress distribution. However, in the structural design criteria simplified stress limits had been adopted without taking account of the strength change with the stress distribution. It is, therefore, important to evaluate the strength of component on the basis of the fracture model for brittle material. Consequently, the strength evaluation program, STEP, on a brittle fracture of ceramic materials based on the competing risk theory had been developed. Two different brittle fracture modes, a surface layer fracture mode dominated by surface flaws and an internal fracture mode by internal flaws, are treated in the STEP code in order to evaluate the strength of brittle fracture. The STEP code uses stress calculation results including complex shape of structures analyzed by the generalized FEM stress analysis code, ABAQUS, so as to be possible to evaluate the strength of brittle fracture for the structures having complicate shapes. This code is, therefore, useful to evaluate the structural integrity of arbitrary shapes of components such as core graphite components in the HTTR, heat exchanger components made of ceramics materials etc. This paper describes the basic equations applying to the STEP code, code system with a combination of the STEP and the ABAQUS codes and the result of the verification analysis. (author)

  20. Relationship between strength qualities and short track speed skating performance in young athletes.

    Science.gov (United States)

    Felser, S; Behrens, M; Fischer, S; Heise, S; Bäumler, M; Salomon, R; Bruhn, S

    2016-02-01

    This study analyzed the relationships between isometric as well as concentric maximum voluntary contraction (MVC) strength of the leg muscles and the times as well as speeds over different distances in 17 young short track speed skaters. Isometric as well as concentric single-joint MVC strength and multi-joint MVC strength in a stable (without skates) and unstable (with skates) condition were tested. Furthermore, time during maximum skating performances on ice was measured. Results indicate that maximum torques during eversion and dorsal flexion have a significant influence on skating speed. Concentric MVC strength of the knee extensors was higher correlated with times as well as speeds over the different distances than isometric MVC strength. Multi-joint MVC testing revealed that the force loss between measurements without and with skates amounts to 25%, while biceps femoris and soleus showed decreased muscle activity and peroneus longus, tibialis anterior, as well as rectus femoris exhibited increased muscle activity. The results of this study depict evidence that the skating times and speeds are primarily influenced by concentric MVC strength of the leg extensors. To be able to transfer the strength onto ice in an optimal way, it is necessary to stabilize the knee and ankle joints. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Studies about strength recovery and generalized relaxation behavior of rock (4)

    International Nuclear Information System (INIS)

    Sanada, Masanori; Kishi, Hirokazu; Hayashi, Katsuhiko; Takebe, Atsuji; Okubo, Seisuke

    2011-11-01

    Surrounding rock failure occurs due to the increasing stress with tunnel excavation and extent of the failure depends on rock strength and rock stress. The NATM (New Austrian Tunneling Method) assumes that supporting effects by shotcrete and rock bolt prevent rock failure maximizing the potential capability of rock mass. Recently, it was found that failed rock just behind tunnel support recovers its strength. This phenomenon should take into account in evaluation of tunnel stability and long-term mechanical behavior of rock mass after closure of a repository for high-level radioactive waste (HLW). Visco-elastic behavior of rock is frequently studied by creep testing, but creep occasionally occurs together with relaxation in-situ due to the effect of various supports and rock heterogeneity. Therefore generalized stress relaxation in which both load and displacement are controlled is proper to study such behavior under the complicated conditions. It is also important to understand rock behavior in tensile stress field which may be developed in the surrounding rock of deposition hole or tunnel by swelling of bentonite or volume expansion of overpack with corrosion after the repository closure. Cores sampled at 'Horonobe Underground Research Laboratory' has been tested to reveal the above-mentioned behavior. Quantitative evaluation and modeling of the rock behavior, however, have not been established mainly because of large scatter of data. As a factor of the large scatter of data, it was expected that the evaporation of moisture from the surface of the test piece influences the test outcome because it tested in the nature. In this study, strength recovery, generalized stress relaxation and two tensile strength tests were carried out using shale sampled in the Wakkanai-formation. As the results, recovery of failed rocks in strength and hydraulic conductivity were observed under a certain condition. We believe this result is very important for the stability evaluation

  2. The influence of the admixture of the fullerene C60 on the strength properties of aluminum and copper under shock-wave loading

    International Nuclear Information System (INIS)

    Bezruchko, G S; Razorenov, S V; Popov, M Y

    2014-01-01

    Hugoniot elastic limit (HEL) and dynamic (spall) strength measurements of pressed aluminum and copper samples with an admixture of the fullerene C60 with 2-5 wt% under shock-wave loading were carried out. The peak pressure in the shock-wave was equal to 6 GPa. The measurements of the elastic-plastic and strength properties were based on the recording and the subsequent analysis of the sample free surface velocity histories, recorded by Velocity Interferometric System for Any Reflection (VISAR). It was found that the admixture of 5 wt% fullerene in aluminum samples led to an increase of the Hugoniot elastic limit for aluminum samples by a factor of ten. The copper samples with the admixture of 2 wt% fullerene also demonstrated an increase of the Hugoniot elastic limit in comparison with commercial copper. The measured values of the Hugoniot elastic limit were equal to 0.82-1.56 GPa for aluminum samples and 1.35-3.46 GPa for copper samples, depending on their porosity. As expected, the spall strength of the samples with fullerene decreased by about three times in comparison with the undoped samples as a result of the influence of the solid fullerene particles which were concentrators of tension stresses in the material under dynamic fracture.

  3. Lifestyle and IVF Outcomes.

    Science.gov (United States)

    Hornstein, Mark D

    2016-12-01

    Whereas much has been written about the prognostic factors associated with outcomes of in vitro fertilization (IVF) such as female age, diagnosis, and ovarian reserve, relatively little attention has been devoted to patient-oriented lifestyles that may influence IVF outcomes. Patients are particularly interested in this topic because many patients wish to partner with their physicians and want to know specific behaviors to improve their chances of IVF success. This brief review is not intended as an exhaustive literature search of all possible lifestyles that may influence assisted reproductive outcome nor is it intended to be a comprehensive review of individual topics. It does give, however, a brief overview of a number of areas in which patient-specific behaviors may influence outcomes in assisted reproduction. Specifically, this review will look at the effects of smoking, alcohol consumption, caffeine, diet, exercise, and exposure to the reproductive toxin bisphenol A on IVF outcomes. © The Author(s) 2016.

  4. Comparison of Strength Gains in Untrained College-Age Females Using Free Weights and Freemotion Machines

    Science.gov (United States)

    Milton, Katherine; Wojcik, Janet R.; Boyd, Joni M.; Bowers, Charles J.

    2018-01-01

    Resistance training has become a preferred method for developing muscular strength among various populations. A variety of resistance training modes are available, but there are mixed outcomes regarding strength development among barbells, dumbbells, and weight machines. The purpose of this study was to investigate the differences in strength…

  5. Auditory development in early amplified children: factors influencing auditory-based communication outcomes in children with hearing loss.

    Science.gov (United States)

    Sininger, Yvonne S; Grimes, Alison; Christensen, Elizabeth

    2010-04-01

    The purpose of this study was to determine the influence of selected predictive factors, primarily age at fitting of amplification and degree of hearing loss, on auditory-based outcomes in young children with bilateral sensorineural hearing loss. Forty-four infants and toddlers, first identified with mild to profound bilateral hearing loss, who were being fitted with amplification were enrolled in the study and followed longitudinally. Subjects were otherwise typically developing with no evidence of cognitive, motor, or visual impairment. A variety of subject factors were measured or documented and used as predictor variables, including age at fitting of amplification, degree of hearing loss in the better hearing ear, cochlear implant status, intensity of oral education, parent-child interaction, and the number of languages spoken in the home. These factors were used in a linear multiple regression analysis to assess their contribution to auditory-based communication outcomes. Five outcome measures, evaluated at regular intervals in children starting at age 3, included measures of speech perception (Pediatric Speech Intelligibility and Online Imitative Test of Speech Pattern Contrast Perception), speech production (Arizona-3), and spoken language (Reynell Expressive and Receptive Language). The age at fitting of amplification ranged from 1 to 72 mo, and the degree of hearing loss ranged from mild to profound. Age at fitting of amplification showed the largest influence and was a significant factor in all outcome models. The degree of hearing loss was an important factor in the modeling of speech production and spoken language outcomes. Cochlear implant use was the other factor that contributed significantly to speech perception, speech production, and language outcomes. Other factors contributed sparsely to the models. Prospective longitudinal studies of children are important to establish relationships between subject factors and outcomes. This study clearly

  6. The effects of rest interval length on acute bench press performance: the influence of gender and muscle strength.

    Science.gov (United States)

    Ratamess, Nicholas A; Chiarello, Christina M; Sacco, Anthony J; Hoffman, Jay R; Faigenbaum, Avery D; Ross, Ryan E; Kang, Jie

    2012-07-01

    The purpose of this study was to investigate the effects of rest interval (RI) length on bench press performance in subjects with disparity in maximum strength. Two cohorts of subjects performed 3 bench press protocols in random order consisting of 3 sets of up to 10 repetitions with 75% of 1-repetition maximum (1RM) using either 1-, 2-, or 3-minute RIs between sets. In the first cohort, 22 men and women were studied to investigate gender influence. In the second cohort, 23 men were tested for 1RM bench press strength and placed into a low 1RM (mean = 80.7 ± 7.5 kg) or high 1RM (mean = 140.6 ± 11.9 kg) experimental group. The number of successful repetitions completed, average power, and velocity for each set were recorded. Women performed significantly more repetitions than men with 1-minute (26.9 ± 4.4 vs. 21.1 ± 3.5), 2-minute (29.0 ± 2.0 vs. 24.0 ± 4.5), and 3-minute (29.7 ± 1.8 vs. 25.8 ± 5.1) RIs. The magnitude of decline in average velocity and power was significantly higher in men than in women. Total number of repetitions performed was significantly greater in the low 1RM group than in the high 1RM group at 1-minute (21.6 ± 5.0 vs. 18.1 ± 2.0) and 2-minute RIs (24.2 ± 5.4 vs. 21.3 ± 2.8). Significant negative correlations were observed between 1RM bench press and total number of repetitions completed for 1- and 2-minute RIs (r = -0.558 and -0.490, respectively). These data indicate that maximal strength plays a role in bench press performance with varying RIs and suggest that shorter RIs may suffice in women to attain a specific volume.

  7. Importance of tie strengths in the prisoner's dilemma game on social networks

    Science.gov (United States)

    Xu, Bo; Liu, Lu; You, Weijia

    2011-06-01

    Though numerous researches have shown that tie strengths play a key role in the formation of collective behavior in social networks, little work has been done to explore their impact on the outcome of evolutionary games. In this Letter, we studied the effect of tie strength in the dynamics of evolutionary prisoner's dilemma games by using online social network datasets. The results show that the fraction of cooperators has a non-trivial dependence on tie strength. Weak ties, just like previous researches on epidemics and information diffusion have shown, play a key role by the maintenance of cooperators in evolutionary prisoner's dilemma games.

  8. The Influence of Problem Based Learning Model toward Students’ Activities and Learning Outcomes on Financial Management Subject

    Directory of Open Access Journals (Sweden)

    Han Tantri Hardini

    2016-12-01

    Full Text Available This research aims to know the influence of problem based learning model toward students’ activities and achievement on Financial Management subject for undergraduate program students of Accounting Education. It was a quantitative research that used true experimental design. Samples of this study were undergraduate program students of Accounting Education in the year of 2014. Class A were control class and class B were experimental class. Data were analyzed by using t-test in order to determine the differences of learning outcomes between control class and experimental class. Then, questionnaires were distributed to gather students’ activities information in their students’ learning model. Findings show that there is an influence of Problem Based Learning model toward students’ activities and learning outcomes on Financial Management subject for undergraduate program students of Accounting Education since t-count ≥ t-table. It is 6.120 ≥ 1.9904. Students’ learning activities with Problem Based Learning model are better than students who are taught by conventional learning model.

  9. Analysis of influence of dosimetric factors on the outcome of I-131 therapy in patients with hyperthyroidism

    International Nuclear Information System (INIS)

    Knapska-Kucharska, M.; Oszukowska, L.; Makarewicz, J.; Lewinski, A.

    2012-01-01

    The influence of dosimetric factors on the outcome of 131 I therapy has been examined in hyperthyroid patients submitted to 131 I treatment. The following factors - which could have influence on the effects of therapy with radioiodine - were analysed: the goitre volume, the thyroid radioiodine uptake after 24 h, and the effective half-life time of 131 I (EHL). Five hundred (500) randomly selected patients with hyperthyroidism, treated with 131 I, were studied. They were divided into three groups (based on clinical examination, hormonal and immunological tests, thyroid scintigraphy and ultrasound imaging). The study shows that the effectiveness of 131 I therapy depends on the thyroid volume and absorbed dose in all the groups of patients and on the thyroid radioiodine uptake and EHL in patients with a single autonomously functioning thyroid nodule. We have failed to determine the borderline D, distinguishing between effective and ineffective therapy. The treatment outcome can be predicted with approximately 70% accuracy, based on minimal absorbed dose

  10. Analysis of influence of dosimetric factors on the outcome of I-131 therapy in patients with hyperthyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Knapska-Kucharska, M.; Oszukowska, L.; Makarewicz, J. [Department of Nuclear Medecine and Oncological Endocrinology, Province Hospital, Zgierz (Poland); Lewinski, A. [Chair and Department of Endocrinology and Metabolic Diseases, Medical University, Lodz (Poland)

    2012-07-01

    The influence of dosimetric factors on the outcome of {sup 131}I therapy has been examined in hyperthyroid patients submitted to {sup 131}I treatment. The following factors - which could have influence on the effects of therapy with radioiodine - were analysed: the goitre volume, the thyroid radioiodine uptake after 24 h, and the effective half-life time of {sup 131}I (EHL). Five hundred (500) randomly selected patients with hyperthyroidism, treated with {sup 131}I, were studied. They were divided into three groups (based on clinical examination, hormonal and immunological tests, thyroid scintigraphy and ultrasound imaging). The study shows that the effectiveness of {sup 131}I therapy depends on the thyroid volume and absorbed dose in all the groups of patients and on the thyroid radioiodine uptake and EHL in patients with a single autonomously functioning thyroid nodule. We have failed to determine the borderline D, distinguishing between effective and ineffective therapy. The treatment outcome can be predicted with approximately 70% accuracy, based on minimal absorbed dose

  11. Effectiveness of Traditional Strength vs. Power Training on Muscle Strength, Power and Speed with Youth: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Behm, David G.; Young, James D.; Whitten, Joseph H. D.; Reid, Jonathan C.; Quigley, Patrick J.; Low, Jonathan; Li, Yimeng; Lima, Camila D.; Hodgson, Daniel D.; Chaouachi, Anis; Prieske, Olaf; Granacher, Urs

    2017-01-01

    Numerous national associations and multiple reviews have documented the safety and efficacy of strength training for children and adolescents. The literature highlights the significant training-induced increases in strength associated with youth strength training. However, the effectiveness of youth strength training programs to improve power measures is not as clear. This discrepancy may be related to training and testing specificity. Most prior youth strength training programs emphasized lower intensity resistance with relatively slow movements. Since power activities typically involve higher intensity, explosive-like contractions with higher angular velocities (e.g., plyometrics), there is a conflict between the training medium and testing measures. This meta-analysis compared strength (e.g., training with resistance or body mass) and power training programs (e.g., plyometric training) on proxies of muscle strength, power, and speed. A systematic literature search using a Boolean Search Strategy was conducted in the electronic databases PubMed, SPORT Discus, Web of Science, and Google Scholar and revealed 652 hits. After perusal of title, abstract, and full text, 107 studies were eligible for inclusion in this systematic review and meta-analysis. The meta-analysis showed small to moderate magnitude changes for training specificity with jump measures. In other words, power training was more effective than strength training for improving youth jump height. For sprint measures, strength training was more effective than power training with youth. Furthermore, strength training exhibited consistently large magnitude changes to lower body strength measures, which contrasted with the generally trivial, small and moderate magnitude training improvements of power training upon lower body strength, sprint and jump measures, respectively. Maturity related inadequacies in eccentric strength and balance might influence the lack of training specificity with the unilateral

  12. Effectiveness of Traditional Strength vs. Power Training on Muscle Strength, Power and Speed with Youth: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    David G. Behm

    2017-06-01

    Full Text Available Numerous national associations and multiple reviews have documented the safety and efficacy of strength training for children and adolescents. The literature highlights the significant training-induced increases in strength associated with youth strength training. However, the effectiveness of youth strength training programs to improve power measures is not as clear. This discrepancy may be related to training and testing specificity. Most prior youth strength training programs emphasized lower intensity resistance with relatively slow movements. Since power activities typically involve higher intensity, explosive-like contractions with higher angular velocities (e.g., plyometrics, there is a conflict between the training medium and testing measures. This meta-analysis compared strength (e.g., training with resistance or body mass and power training programs (e.g., plyometric training on proxies of muscle strength, power, and speed. A systematic literature search using a Boolean Search Strategy was conducted in the electronic databases PubMed, SPORT Discus, Web of Science, and Google Scholar and revealed 652 hits. After perusal of title, abstract, and full text, 107 studies were eligible for inclusion in this systematic review and meta-analysis. The meta-analysis showed small to moderate magnitude changes for training specificity with jump measures. In other words, power training was more effective than strength training for improving youth jump height. For sprint measures, strength training was more effective than power training with youth. Furthermore, strength training exhibited consistently large magnitude changes to lower body strength measures, which contrasted with the generally trivial, small and moderate magnitude training improvements of power training upon lower body strength, sprint and jump measures, respectively. Maturity related inadequacies in eccentric strength and balance might influence the lack of training specificity with

  13. Convergence of a strengths perspective and youth development: Toward youth promotion practice

    Directory of Open Access Journals (Sweden)

    Jeong Woong Cheon

    2008-12-01

    Full Text Available In recent years, increased attention has been paid to the development and application of the strengths perspective and positive youth development. This paper develops youth promotion practice as a convergence of a strengths perspective and youth development principles. Historical and contemporary contexts of a problem-focused perspective in social work with adolescents are reviewed and a critique developed with emphasis on the evolution of strengths-focused practices. The importance and possibility of combining the strengths perspective and youth development toward youth promotion practice are addressed. Youth promotion is defined as a process of enhancing youth strengths and resources to promote positive outcomes and help young people be healthy adults. Complementary aspects of the two perspectives are expected to support and supplement the strengths and weaknesses of each perspective in synergistic ways. Several advantages of youth promotion practice are discussed as well as its implications for improved social work practices with adolescents.

  14. In vitro Assessment of Influence of Various Bleaching Protocols on the Strength of Ceramic Orthodontic Brackets bonded to Bleached Tooth Surface: A Comparative Study.

    Science.gov (United States)

    Iska, Divya; Devanna, Raghu; Singh, Madhvi; Chitumalla, Rajkiran; Balasubramanian, Sai C Bala; Goutam, Manish

    2017-12-01

    Esthetics is one of the common issues because of which patients consult dental orthodontic treatment. Two ways of tooth bleaching are available these days, which includes in-office bleach and home bleach. Various bleaching protocols are available these days for treating the tooth surfaces. Hence, we planned the present study for investigating the impact of various intracoronal bleaching protocols on shear bond strength of ceramic brackets bonded to tooth surface after bleaching. The present study included assessment of 100 extracted maxillary central incisors with the integrated buccal surface. A resin block was made and individual teeth were embedded in each block. Root canal therapy procedure was performed in all the teeth, after which 2 mm short of tooth apex up to the level of cementoenamel junction, removal of the root canal filling was done. All the samples were broadly divided into four study groups with 25 samples in each group. Bleaching procedure was carried in all the samples intracoronally followed by testing of shear bond strength using universal force testing machine. Following the modified adhesive remnant index (AI), assessment of remaining adhesive on the brackets was done. All the results were compiled and analyzed by Statistical Package for the Social Sciences (SPSS) software version 17.0. In the control group, mean shear bond strength was found to be 17.9 MPa. While comparing the carbamide peroxide (CP) group with sodium perborate study group, we observed a statistically significant difference. Nonsignificant results were obtained while comparing the shear bond strength in between sodium perborate group and hydrogen peroxide (HP) group. Intracoronal bleaching does affect the shear bond strength of ceramic brackets. Sodium perborate bleaching influences shear bond strength more strongly than other bleaching agents such as CP and HP. In patients undergoing orthodontic treatment, HP is a preferred agent where bleaching has to be followed by

  15. Fire performance, mechanical strength and dimensional stability of wood flour–polyethylene composites under the influence of different fire retardants

    Directory of Open Access Journals (Sweden)

    Mehdi Roohani

    2017-05-01

    Full Text Available Flammability is one of the most important parameters that often limit the application range of wood plastic composites. Therefore, the improvements of retardancy performance of these products have a considerable impact. The aim of this work was to evaluate the influence of expandable graphite (EG and its combination with aluminum tirhydroxide (ATH, inorganic phosphate (IP and melamine borate (MB on the flammability of wood flour–polyethylene composites. Composites were prepared by the melt compounding method and cone calorimetry as well as limited oxygen index (LOI tests was employed to study their flammability properties. Also, the effect of different fire retardants on the mechanical strength and water uptake of samples were investigated. Cone calorimetry characterization indicated that with incorporation of fire retardans heat release rate and burning rate decrease and char residual as well as the time to ignition increase. These findings ascribed to formation of char layer by fire retardants. The combination of EG and other fire retardants yielded better improvements in flame retardancy in comparison to the sample that has just EG as flame retardant. The LOI test was used to determine the lowest concentration of oxygen at which a material will maintain combustion in a flowing mixture of oxygen and nitrogen. The results showed that inclusion of fire retardants improve the LOI of sample. Furthermore, the presence of fire retardants decreased the tensile and flexural resistance (strength and modules and impact strength of samples, and increased the water absorption as well as thickness swelling. Generally, among the different treatments examined, the EG–ATH retardancy system showed highest potential in flame retardancy of composites.

  16. Influence of body mass index on the outcome of brachial plexus surgery: are there any differences between elbow and shoulder results?

    Science.gov (United States)

    Socolovsky, Mariano; Martins, Roberto S; Di Masi, Gilda; Bonilla, Gonzalo; Siqueira, Mario G

    2014-12-01

    Body mass index (BMI) has recently been identified as a predictor of outcomes following reconstructive surgery of shoulder palsies. In this study, we sought to determine if the same holds true for the reconstruction of elbow flexion. Forty patients who had undergone partial ulnar-to-biceps nerve transfer (Oberlin's procedure) for shoulder palsy were assessed and compared against 18 previously reported patients who had undergone reconstruction for elbow palsies. The British Medical Research Council (BMRC) scale and an index dividing shoulder abduction strength in the affected arm by healthy arm were recorded. All patients had undergone surgery within 12 months of injury and had ≥ 12 months of follow-up. M4 or M3 biceps strength was obtained in 90 % of patients. Final strength on the affected side averaged 5.8 kg, versus 20.2 kg on the normal side, for a mean recovery index score of 0.30. In this sample of 40 patients, BMI did not predict percentage strength or BMRC grade recovery. Neither did age, number of roots involved, the affected side, nor time to surgery. Comparing patients with elbow versus shoulder reconstruction, there were no differences, except that patients undergoing Oberlin's procedure had a statistically longer duration of time between injury and surgical repair (7.4 vs 5.1 months, p surgery.

  17. Culture and ethnicity influence outcomes of the Scoliosis Research Society Instrument in adolescent idiopathic scoliosis.

    Science.gov (United States)

    Morse, Lee Jae; Kawakami, Noriaki; Lenke, Lawrence G; Sucato, Daniel J; Sanders, James O; Diab, Mohammad

    2012-05-20

    Retrospective comparative study. To report preoperative differences in the Scoliosis Research Society Outcomes Instrument (SRS-30) between multiple US ethnicities and native Japanese and Korean children with adolescent idiopathic scoliosis (AIS). The SRS-24 was developed in a US cohort with AIS. Comparative studies using the SRS-24 between US and Japanese patients showed differences, suggesting that culture might affect functional outcome. Preoperative SRS-30 outcomes were collected from 1853 children with AIS from 6 different ethnic groups: US white (1234), black (213), Hispanic (78), and Asian (29), as well as native Japanese (192) and Koreans (107). Analysis of covariance of 4 SRS-30 domains (pain, appearance, activity, and mental) was compared between groups adjusting for differences in age, sex, major curve magnitude, and body mass index. Pairwise comparisons of the 4 SRS-30 domains were adjusted for multiple comparisons, using Bonferroni correction. A P value of less than 0.05 was considered significant. Significant differences between ethnicities were found in all domains (P Culture and ethnicity influence SRS-30 outcomes in AIS. Whites reported more pain than Japanese and Koreans. Japanese and Koreans had the lowest appearance scores. Koreans additionally were distinguished by the lowest activity, mental, and total scores. These cultural and ethnic differences must be taken into account when counseling patients with AIS and studying functional outcomes.

  18. The effect of protein and carbohydrate supplementation on strength training outcome of rehabilitation in ACL patients

    DEFF Research Database (Denmark)

    Holm, Lars; Esmarck, Birgitte; Mizuno, Masao

    2006-01-01

    supplementation groups: Protein+Carbohydrate (PC), Isocaloric-Carbohydrate (IC), or Placebo (PL), ingesting the supplementation immediately after each of 36 training sessions. Determined from images of thigh cross-sections (magnetic resonance imaging) the hypertrophy of the quadriceps muscle differed....... The results from this study demonstrate that restoration of the distal vasti muscle mass and knee extension muscle strength with resistance training is promoted further by protein-containing nutrient supplementation immediately after single exercise sessions. Thus, exercise-related protein supplementation may...... was therefore to investigate if nutrient supplementation during 12 weeks of conservative rehabilitation strength training could enhance hypertrophy and strength of the quadriceps muscle in ACL-injured patients. Twenty-six ACL-injured men and women were included and randomly distributed into three...

  19. The influence of particles of a minor component on the matrix strength of sodium chloride

    NARCIS (Netherlands)

    Van Veen, B.; van der Voort Maarschalk, Kees; Bolhuis, G.K; Gons, M.; Zuurman, K.; Frijlink, H.W

    2002-01-01

    This paper deals with the matrix strength of sodium chloride particles in pure sodium chloride tablets and in tablets compressed from binary mixtures of sodium chloride with low concentrations of pregelatinised starch. Because this study concerns the strength of the sodium chloride matrix, the

  20. The influence of the diffusion of responsibility effect on outcome evaluations: electrophysiological evidence from an ERP study.

    Science.gov (United States)

    Li, Peng; Jia, Shiwei; Feng, Tingyong; Liu, Qiang; Suo, Tao; Li, Hong

    2010-10-01

    Previous studies have revealed that personal responsibility has an influence on outcome evaluation, although the way this influence works is still unclear. This study imitated the phenomenon of responsibility diffusion in a laboratory to examine the influence of the effect of responsibility diffusion on the processing of outcome evaluation using the event-related potential (ERP) technique. Participants of the study were required to perform the gambling task individually in the high-responsibility condition and with others in the low-responsibility scenario. Self-rating results showed that the participants felt more responsible for monetary loss and believed that they had more contributions to the monetary gains in the high-responsibility condition than in the low-responsibility situation. Both the feedback-related negativity (FRN) and the P300 were sensitive to the responsibility level, as evidenced by the enhanced amplitudes in the high-responsibility condition for both components. Further correlation analysis showed a negative correlation between FRN amplitudes and subjective rating scores (i.e., the higher the responsibility level, the larger the FRN amplitude). The results probably indicate that the FRN and P300 reflect personal responsibility processing under the social context of diffusion of responsibility. Copyright 2010 Elsevier Inc. All rights reserved.

  1. Analysis on geometry-aware received signal strength based ...

    African Journals Online (AJOL)

    These handle different scenarios such as environment, adaptation, hybridization and the choice of context is dependent on user requirements. This paper present geometry-aware received signal strength (RSS) based positioning techniques where the influences of the geometries of the BSs (where location estimation ...

  2. Assistive technology outcomes in post-secondary students with disabilities: the influence of diagnosis, gender, and class-level.

    Science.gov (United States)

    Malcolm, Matt P; Roll, Marla C

    2017-11-01

    This study investigated how outcomes of assistive technology (AT) services for college students with disabilities are influenced by diagnosis, gender and class-level (e.g., Freshman). Students' pre- and post-intervention ratings of their performance and satisfaction of common academic tasks (using the Canadian Occupational Performance Measure, COPM) were analyzed, as well as students' responses on a survey about AT service provision, use, and preferences. Data from 455 students revealed "learning disability" to be the most prevalent diagnosis (38%), similar numbers of females and males served, and Freshmen (23.1%) as the largest class-level seeking AT services. For COPM data, each two-way analysis of variance (ANOVA) (grouping variable = diagnosis) revealed that pre-post change scores significantly improved for the entire sample, and that students with a mood disorder experienced the greatest changes compared to other diagnoses. COPM scores significantly and similarly improved for females and males, and across class levels. AT Survey ratings about timeliness of services and independent AT use were significantly lower for students with mobility deficits/pain and neurological damage, respectively. Gender and class-level variables did not significantly impact AT Survey ratings. The study results reveal that features of a college student's diagnosis may influence AT service outcomes, and student-perceptions of AT services ability to use AT. Implications for Rehabilitation College students who are Freshman and/or who have a learning disability are the most prevalent students referred for campus-based assistive technology services. While student ratings of academic task performance significantly increase across diagnostic groupings, these improvements were greatest for those with a mood disorder compared to other diagnostic groups. Service-providers should consider that features of certain diagnoses or disabilities may influence the student?s perception of AT service

  3. Relationship between agility and lower limb muscle strength, targeting university badminton players.

    Science.gov (United States)

    Sonoda, Takuya; Tashiro, Yuto; Suzuki, Yusuke; Kajiwara, Yu; Zeidan, Hala; Yokota, Yuki; Kawagoe, Mirei; Nakayama, Yasuaki; Bito, Tsubasa; Shimoura, Kanako; Tatsumi, Masataka; Nakai, Kengo; Nishida, Yuichi; Yoshimi, Soyoka; Aoyama, Tomoki

    2018-02-01

    [Purpose] Targeting university badminton players, this study investigated the relationship between agility, which is associated with performance in badminton, and lower limb muscle strength, and examined which muscles influence agility. [Subjects and Methods] A total of 23 male university badminton players were evaluated for side-shuffle test scores and lower limb strength. The relationships between agility, lower limb strength, and duration of experience playing badminton were evaluated using a correlation analysis. Moreover, the relationship between agility and lower limb strength was evaluated by partial correlation analysis, adjusting for the effects of experience of each badminton player. [Results] The agility score correlated with hip extension and ankle plantar flexion strength, with adjustment for badminton experience. [Conclusion] This study suggests that hip extension training and improvement in ankle plantar flexion strength may improve agility.

  4. Retrospective Attention Interacts with Stimulus Strength to Shape Working Memory Performance.

    Science.gov (United States)

    Wildegger, Theresa; Humphreys, Glyn; Nobre, Anna C

    2016-01-01

    Orienting attention retrospectively to selective contents in working memory (WM) influences performance. A separate line of research has shown that stimulus strength shapes perceptual representations. There is little research on how stimulus strength during encoding shapes WM performance, and how effects of retrospective orienting might vary with changes in stimulus strength. We explore these questions in three experiments using a continuous-recall WM task. In Experiment 1 we show that benefits of cueing spatial attention retrospectively during WM maintenance (retrocueing) varies according to stimulus contrast during encoding. Retrocueing effects emerge for supraliminal but not sub-threshold stimuli. However, once stimuli are supraliminal, performance is no longer influenced by stimulus contrast. In Experiments 2 and 3 we used a mixture-model approach to examine how different sources of error in WM are affected by contrast and retrocueing. For high-contrast stimuli (Experiment 2), retrocues increased the precision of successfully remembered items. For low-contrast stimuli (Experiment 3), retrocues decreased the probability of mistaking a target with distracters. These results suggest that the processes by which retrospective attentional orienting shape WM performance are dependent on the quality of WM representations, which in turn depends on stimulus strength during encoding.

  5. Influence of political opposition and compromise on conservation outcomes in the Tongass National Forest, Alaska.

    Science.gov (United States)

    Beier, Colin M

    2008-12-01

    To understand how a highly contentious policy process influenced a major conservation effort, I examined the origins, compromises, and outcomes of the Alaska National Interest Lands Conservation Act of 1980 (ANILCA) for the Tongass National Forest. Tongass wilderness designation was among the most controversial issues in the ANILCA debate, and it faced strong opposition from influential lawmakers, land managers, and Alaska residents. To investigate the influence of this opposition on Tongass conservation outcomes, I conducted a gap analysis of Tongass reserves and a policy analysis of the ANILCA debate and traced the influence of specific interests through the amendments, negotiations, and resulting compromises needed to enact ANILCA. Overall, I found that Tongass reserves comprise a broadly representative cross-section of ecosystems and species habitats in southeastern Alaska. Redrawn reserve boundaries, industry subsidies, and special access regulations reflected compromises to minimize the impact of wilderness conservation on mining, timber, and local stakeholder interests, respectively. Fragmentation of the Admiralty Island National Monument-the most ecologically valuable and politically controversial reserve-resulted from compromises with Alaskan Native (indigenous peoples of Alaska) corporations and timber interests. Despite language to accommodate "reasonable access" to wilderness reserves, ongoing access limitations highlight the concerns of Alaska residents that opposed ANILCA several decades ago. More broadly, the Tongass case suggests that early and ambitious conservation action may offset strong political opposition; compromises needed to establish key reserves often exacerbate development impacts in unprotected areas; and efforts to minimize social conflicts are needed to safeguard the long-term viability of conservation measures.

  6. The Influence of Hearing Aid Use on Outcomes of Children With Mild Hearing Loss.

    Science.gov (United States)

    Walker, Elizabeth A; Holte, Lenore; McCreery, Ryan W; Spratford, Meredith; Page, Thomas; Moeller, Mary Pat

    2015-10-01

    This study examined the effects of consistent hearing aid (HA) use on outcomes in children with mild hearing loss (HL). Five- or 7-year-old children with mild HL were separated into 3 groups on the basis of patterns of daily HA use. Using analyses of variance, we compared outcomes between groups on speech and language tests and a speech perception in noise task. Regression models were used to investigate the influence of cumulative auditory experience (audibility, early intervention, HA use) on outcomes. Full-time HA users demonstrated significantly higher scores on vocabulary and grammar measures compared with nonusers. There were no significant differences between the 3 groups on articulation or speech perception measures. After controlling for the variance in age at confirmation of HL, level of audibility, and enrollment in early intervention, only amount of daily HA use was a significant predictor of grammar and vocabulary. The current results provide evidence that children's language development benefits from consistent HA use. Nonusers are at risk in areas such as vocabulary and grammar compared with other children with mild HL who wear HAs regularly. Service providers should work collaboratively to encourage consistent HA use.

  7. Risk factors for worsened muscle strength after the surgical treatment of arteriovenous malformations of the eloquent motor area.

    Science.gov (United States)

    Lin, Fuxin; Zhao, Bing; Wu, Jun; Wang, Lijun; Jin, Zhen; Cao, Yong; Wang, Shuo

    2016-08-01

    OBJECT Case selection for the surgical treatment of arteriovenous malformations (AVMs) of the eloquent motor area remains challenging. The aim of this study was to determine the risk factors for worsened muscle strength after surgery in patients with this disorder. METHODS At their hospital the authors retrospectively studied 48 consecutive patients with AVMs involving motor cortex and/or the descending pathway. All patients had undergone preoperative functional MRI (fMRI) and diffusion tensor imaging (DTI), followed by resection. Both functional and angioarchitectural factors were analyzed with respect to the change in muscle strength. Functional factors included lesion-to-corticospinal tract distance (LCD) on DTI and lesion-to-activation area distance (LAD) and cortical reorganization on fMRI. Based on preoperative muscle strength, the changes in muscle strength at 1 week and 6 months after surgery were defined as short-term and long-term surgical outcomes, respectively. Statistical analysis was performed using the statistical package SPSS (version 20.0.0, IBM Corp.). RESULTS Twenty-one patients (43.8%) had worsened muscle strength 1 week after surgery. However, only 10 patients (20.8%) suffered from muscle strength worsening 6 months after surgery. The LCD was significantly correlated with short-term (p 0 mm (p = 0.009) and LCD > 5 mm (p 0 mm group and LCD > 5 mm group (p = 0.116). Nidus size was the other significant predictor of short-term (p = 0.021) and long-term (p = 0.016) outcomes. For long-term outcomes, the area under the ROC curve (AUC) was 0.728, and the cutoff point was 3.6 cm. Spetzler-Martin grade was not associated with short-term surgical outcomes (0.143), although it was correlated with long-term outcomes (0.038). CONCLUSIONS An AVM with a nidus in contact with tracked eloquent fibers (LCD = 0) and having a large size is more likely to be associated with worsened muscle strength after surgery in patients with eloquent motor area AVMs. Surgical

  8. Influence of Disease and Patient Characteristics on Daratumumab Exposure and Clinical Outcomes in Relapsed or Refractory Multiple Myeloma

    DEFF Research Database (Denmark)

    Yan, Xiaoyu; Clemens, Pamela L; Puchalski, Thomas

    2018-01-01

    OBJECTIVE: The aim of this study was to understand the influence of disease and patient characteristics on exposure to daratumumab, an immunoglobulin Gκ (IgGκ) monoclonal antibody, and clinical outcomes in relapsed or refractory multiple myeloma (MM). PATIENTS AND METHODS: Baseline myeloma type, ...

  9. Experimental and numerical investigations of beryllium strength models using the Rayleigh-Taylor instability

    Energy Technology Data Exchange (ETDEWEB)

    Henry de Frahan, M. T., E-mail: marchdf@umich.edu; Johnsen, E. [Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Belof, J. L.; Cavallo, R. M.; Ancheta, D. S.; El-dasher, B. S.; Florando, J. N.; Gallegos, G. F.; LeBlanc, M. M. [Lawrence Livermore National Laboratory Livermore, California 94551-0808 (United States); Raevsky, V. A.; Ignatova, O. N.; Lebedev, A. [Russian Federal Nuclear Center-VNIIEF, Sarov 607188 (Russian Federation)

    2015-06-14

    We present a set of high explosive driven Rayleigh-Taylor strength experiments for beryllium to produce data to distinguish predictions by various strength models. Design simulations using existing strength model parameterizations from Steinberg-Lund and Preston-Tonks-Wallace (PTW) suggested an optimal design that would delineate between not just different strength models, but different parameters sets of the PTW model. Application of the models to the post-shot results, however, suggests growth consistent with little material strength. We focus mostly on efforts to simulate the data using published strength models as well as the more recent RING relaxation model developed at VNIIEF. The results of the strength experiments indicate weak influence of strength in mitigating the growth with the RING model coming closest to predicting the material behavior. Finally, we present shock and ramp-loading recovery experiments.

  10. Strength training for the warfighter.

    Science.gov (United States)

    Kraemer, William J; Szivak, Tunde K

    2012-07-01

    Optimizing strength training for the warfighter is challenged by past training philosophies that no longer serve the modern warfighter facing the "anaerobic battlefield." Training approaches for integration of strength with other needed physical capabilities have been shown to require a periodization model that has the flexibility for changes and is able to adapt to ever-changing circumstances affecting the quality of workouts. Additionally, sequencing of workouts to limit over-reaching and development of overtraining syndromes that end in loss of duty time and injury are paramount to long-term success. Allowing adequate time for rest and recovery and recognizing the negative influences of extreme exercise programs and excessive endurance training will be vital in moving physical training programs into a more modern perspective as used by elite strength-power anaerobic athletes in sports today. Because the warfighter is an elite athlete, it is time that training approaches that are scientifically based are updated within the military to match the functional demands of modern warfare and are given greater credence and value at the command levels. A needs analysis, development of periodized training modules, and individualization of programs are needed to optimize the strength of the modern warfighter. We now have the knowledge, professional coaches and nonprofit organization certifications with continuing education units, and modern training technology to allow this to happen. Ultimately, it only takes command decisions and implementation to make this possible.

  11. [Effect of core: dentin thickness ratio on the flexure strength of IPS Empress II heat-pressed all-ceramic restorative material].

    Science.gov (United States)

    Liu, Yi-hong; Feng, Hai-lan; Bao, Yi-wang; Qiu, Yan

    2007-02-18

    To evaluate the effect of core:dentin thickness ratio on the flexure strength, fracture mode and origin of bilayered IPS Empress II ceramic composite specimens. IPS Empress II core ceramic, dentin porcelain and bilayered composite specimens with core:dentin thickness ratio of 2:1 and 1:1 were tested in three-point flexure strength. Mean strengths and standard deviations were determined. The optical microscopy was employed for identification of the fracture mode and origin. The flexure strength of dentin porcelain was the smallest(62.7 MPa), and the strength of bilayered composite specimens was smaller than single-layered core ceramic(190.2 MPa). The core: dentin ratio did not influence the strength of bilayered composite specimens. The frequency of occurrence of bilayered specimen delaminations was higher in the group of core: dentin thickness ratio of 1:1 than in the group of 2:1. IPS Empress II core ceramic was significantly stronger than veneering dentin porcelain. Core:dentin thickness ratio could significantly influence the fracture mode and origin, and bilayered IPS Empress II ceramic composite specimens showed little influence in the fracture strength.

  12. Tensile strength of AK7 alloy after treatment by exothermic mixtures

    International Nuclear Information System (INIS)

    Lipinski, T.

    2002-01-01

    The paper presents the influence of treatment by chemical compounds giving exothermic effect on the tensile strength of AK7 alloy. The research was carried out on 1100 g of the alloy in classical mould. The chemical mixture was composed of Na 2 B 4 O 7 , NaNO 3 and Cr 2 O 3 + AlNi. The studies were conducted following a mathematical experiment plan. The action of Borax was free from interference whereas the two residual constituents were mass-dependence. Excess NaNO 3 was caused by the reduction of the value of the tensile strength. Cr 2 O 3 + AlNi strengthened the influence of NaNO 3 . It was found that the blending of Na 2 B 4 O 7 and NaNO 3 on weight ratio 1,5 to 1 and of NaNO 3 and Cr 2 O 3 + AlNi on weight ratio 1 to 3 improved the tensile strength of the AK7 alloy after treatment. (author)

  13. Feasibility of progressive strength training implemented in the acute ward after hip fracture surgery.

    Directory of Open Access Journals (Sweden)

    Lise Kronborg

    Full Text Available Patients with a hip fracture lose more than 50% knee-extension strength in the fractured limb within one week of surgery. Hence, immediate progressive strength training following hip fracture surgery may be rational, but the feasibility unknown.To examine the feasibility of in-hospital progressive strength training implemented in the acute ward following hip fracture surgery, based on pre-specified criteria for feasibility.A prospective cohort study conducted in an acute orthopedic hip fracture unit at a university hospital. A consecutive sample of 36 patients, 18 with a cervical and 18 with a trochanteric hip fracture (27 women and 9 men, mean (SD age of 79.4 (8.3 years were included between June and December 2012.A daily (on weekdays program of progressive knee-extension strength training for the fractured limb, using ankle weight cuffs in 3 sets of 10 repetition maximum loadings.The primary outcome was the change in training load (kg during the knee-extension strength training. The secondary outcomes were changes in hip fracture-related pain and maximal isometric knee-extension strength.The strength training was commenced at a mean of 2.4 (0.7 days after surgery. The training loads (kilograms lifted increased from 1.6 (0.8 to 4.3 (1.7 kg over 4.3 (2.2 training sessions (P<.001. The maximal isometric knee-extension strength of the fractured limb increased from 0.37 (0.2 to 0.61 (0.3 Nm/kg (P<.001, while the average strength deficit in the fractured limb decreased from 50% to 32% (% non-fractured, P<.001. Only 3 of 212 sessions were not performed because of severe hip fracture-related pain.Progressive knee-extension strength training of the fractured limb commenced in the acute ward seems feasible, and may reduce strength asymmetry between limbs without hip pain interfering. The clinical efficacy needs confirmation in a randomized controlled design.ClinicalTrials.gov ID: NCT01616030.

  14. Mucosal Perforation During Laparoscopic Heller Myotomy Has No Influence on Final Treatment Outcome.

    Science.gov (United States)

    Salvador, Renato; Spadotto, Lorenzo; Capovilla, Giovanni; Voltarel, Guerrino; Pesenti, Elisa; Longo, Cristina; Cavallin, Francesco; Nicoletti, Loredana; Ruol, Alberto; Valmasoni, Michele; Merigliano, Stefano; Costantini, Mario

    2016-12-01

    The aims of the study were (a) to examine the final outcome in patients experiencing accidental mucosal perforation during laparoscopic Heller myotomy with Dor fundoplication (LHD) and (b) to evaluate whether perforation episodes might influence the way in which surgeons subsequently approached the LHD procedure. We studied all consecutive patients that underwent LHD between 1992 and 2015. Patients were divided into two main groups: those who experienced an intraoperative mucosal perforation (group P) and those whose LHD was uneventful (group NP). Two additional groups were compared: group A, which consisted of patients operated by a given surgeon immediately before a perforation episode occurred, and group B, which included those operated immediately afterwards. Eight hundred seventy-five patients underwent LHD; a mucosal perforation was detected in 25 patients (2.9 %), which was found unrelated to patients' symptom's score and age, radiological stage, manometric pattern, or the surgeon's experience. The median postoperative symptom score was similar for the two groups as the failure rate: 92 failures in group NP (10.8 %) and 4 in group P (16 %) (p = 0.34); moreover, symptoms recurred in 2 patients of group A (10 %) and 3 patients of group B (15 %) (p = 0.9). Accidental perforation during LHD is infrequent and impossible to predict on the grounds of preoperative therapy or the surgeon's personal experience. Despite a longer surgical procedure and hospital stay, the outcome of LHD is much the same as for patients undergoing uneventful myotomy. A recent mucosal perforation does not influence the surgeon's subsequent performance.

  15. Influence of field strength, coil type and image resolution on assessment of synovitis by unenhanced MRI--a comparison with contrast-enhanced MRI

    DEFF Research Database (Denmark)

    Eshed, Iris; Krabbe, Simon; Østergaard, Mikkel

    2015-01-01

    post-contrast T1-weighted sequence was used as gold standard reference. RESULTS: Fair-good agreement (ICC=0.38--0.72) between the standard reference and the different STIR protocols (best agreement with extremity coil and small voxel size at 1.5 T). The accuracy for presence/absence of synovitis...... is only moderately reliable for assessing hand synovitis in RA, when contrast-enhanced MRI is considered the gold standard reference. Contrast injection, field strength and coil type influence synovitis assessment, and should be considered before performing MRI in clinical trials and practice. KEY POINTS...

  16. Specific strength training compared with interdisciplinary counseling for girls with tension-type headache: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Tornøe B

    2016-05-01

    headache on a random day decreased over the 22 weeks by 0.65 (0.50–0.84 (odds ratio [95% confidence interval]. For both groups, neck extension strength decreased significantly with a decrease in cervicothoracic extension/flexion ratio to 1.7, indicating a positive change in muscle balance. In the training group, shoulder strength increased ≥10% in 5/20 girls and predicted VO2max increased ≥15% for 4/20 girls. In the training group, 50% of girls with a headache reduction of ≥30% had an increase in VO2max >5%. For the counseling group, this was the case for 29%. A 24-month follow-up on HRQOL for the pooled sample revealed statistically significant improvements. Fifty-five percent of the girls reported little to none disability. Conclusion: The results indicate that both physical health and HRQOL can be influenced significantly by physical exercise and nurse counseling. More research is needed to examine the relationship between physical exercise, VO2max, and TTH in girls. Thus, empowering patient education to promote maximum possible outcomes for all children needs more attention. Keywords: empowering patient education, neck and shoulder muscles, muscular fitness, cardiovascular fitness, headache, child, health and physical therapy 

  17. Influence of sex on chronic obstructive pulmonary disease risk and treatment outcomes

    Directory of Open Access Journals (Sweden)

    Aryal S

    2014-10-01

    Full Text Available Shambhu Aryal,1 Enrique Diaz-Guzman,2 David M Mannino3 1Division of Pulmonary, Allergy and Critical Care Medicine, Duke University, Durham, NC, 2Division of Pulmonary, Allergy and Critical Care, University of Alabama, Birmingham, AL, 3Department of Preventive Medicine and Environmental Health, University of Kentucky, Lexington, KY, USA Abstract: Chronic obstructive pulmonary disease (COPD, one of the most common chronic diseases and a leading cause of death, has historically been considered a disease of men. However, there has been a rapid increase in the prevalence, morbidity, and mortality of COPD in women over the last two decades. This has largely been attributed to historical increases in tobacco consumption among women. But the influence of sex on COPD is complex and involves several other factors, including differential susceptibility to the effects of tobacco, anatomic, hormonal, and behavioral differences, and differential response to therapy. Interestingly, nonsmokers with COPD are more likely to be women. In addition, women with COPD are more likely to have a chronic bronchitis phenotype, suffer from less cardiovascular comorbidity, have more concomitant depression and osteoporosis, and have a better outcome with acute exacerbations. Women historically have had lower mortality with COPD, but this is changing as well. There are also differences in how men and women respond to different therapies. Despite the changing face of COPD, care providers continue to harbor a sex bias, leading to underdiagnosis and delayed diagnosis of COPD in women. In this review, we present the current knowledge on the influence of sex on COPD risk factors, epidemiology, diagnosis, comorbidities, treatment, and outcomes, and how this knowledge may be applied to improve clinical practices and advance research. Keywords: chronic obstructive lung disease, sex, smoking, comorbidity, sex bias

  18. STRENGTH OF NANOMODIFIED HIGH-STRENGTH LIGHTWEIGHT CONCRETES

    Directory of Open Access Journals (Sweden)

    NOZEMTСEV Alexandr Sergeevich

    2013-02-01

    Full Text Available The paper presents the results of research aimed at development of nanomodified high-strength lightweight concrete for construction. The developed concretes are of low average density and high ultimate compressive strength. It is shown that to produce this type of concrete one need to use hollow glass and aluminosilicate microspheres. To increase the durability of adhesion between cement stone and fine filler the authors offer to use complex nanodimensinal modifier based on iron hydroxide sol and silica sol as a surface nanomodifier for hollow microspheres. It is hypothesized that the proposed modifier has complex effect on the activity of the cement hydration and, at the same time increases bond strength between filler and cement-mineral matrix. The compositions for energy-efficient nanomodified high-strength lightweight concrete which density is 1300…1500 kg/m³ and compressive strength is 40…65 MPa have been developed. The approaches to the design of high-strength lightweight concrete with density of less than 2000 kg/m³ are formulated. It is noted that the proposed concretes possess dense homogeneous structure and moderate mobility. Thus, they allow processing by vibration during production. The economic and practical implications for realization of high-strength lightweight concrete in industrial production have been justified.

  19. Influence of previous acid etching on bond strength of universal adhesives to enamel and dentin.

    Science.gov (United States)

    Torres, Carlos Rocha Gomes; Zanatta, Rayssa Ferreira; Silva, Tatiane Josefa; Huhtala, Maria Filomena Rocha Lima; Borges, Alessandra Bühler

    2017-01-01

    The objective of this study was to evaluate the effect of acid pretreatment on the bond strength of composite resin bonded to enamel and dentin with 2 different universal self-etching adhesives. The null hypothesis was that the acid treatment performed prior to adhesive application would not significantly change the bond strength to enamel or dentin for either universal adhesive tested. A sample of 112 bovine incisors were selected and embedded in acrylic resin. Half were ground until a flat enamel surface was obtained, and the other half were polished until a 6 × 6-mm area of dentin was exposed, resulting into 2 groups (n = 56). The enamel and dentin groups were divided into 2 subgroups according to the adhesive system applied: Futurabond U or Scotchbond Universal. Each of these subgroups was divided into 2 additional subgroups (n = 14); 1 subgroup received phosphoric acid pretreatment, and 1 subgroup did not. The bond strength was assessed with a microtensile test. Data from enamel and dentin specimens were analyzed separately using 1-way analysis of variance. The acid pretreatment did not significantly change the bond strength of the adhesives tested, either to enamel (P = 0.4161) or to dentin (P = 0.4857). The acid etching pretreatment did not affect the bond strength to dentin and enamel when the tested universal multipurpose adhesive systems were used.

  20. Mechanistic dissimilarities between environmentally-influenced fatigue-crack propagation at near-threshold and higher growth rates in lower-strength steels

    Energy Technology Data Exchange (ETDEWEB)

    Suresh, S.; Ritchie, R. O.

    1981-11-01

    The role of hydrogen gas in influencing fatigue crack propagation is examined for several classes of lower strength pressure vessel and piping steels. Based on measurements over a wide range of growth rates from 10/sup -8/ to 10/sup -2/ mm/cycle, crack propagation rates are found to be significantly higher in dehumidified gaseous hydrogen compared to moist air in two distinct regimes of crack growth, namely (i) at the intermediate range of growth typically above approx. 10/sup -5/ mm/cycle, and (ii) at the near-threshold region below approx. 10/sup -6/ mm/cycle approaching lattice dimensions per cycle. Both effects are seen at maximum stress intensities (K/sub max/) far below the sustained-load threshold stress intensity for hydrogen-assisted cracking (K/sub Iscc/). Characteristics of environmentally influenced fatigue crack growth in each regime are shown to be markedly different with regard to fractography and the effect of such variables as load ratio and frequency. It is concluded that the primary mechanisms responsible for the influence of the environment in each regime are distinctly different. Whereas corrosion fatigue behavior at intermediate growth rates can be attributed to hydrogen embrittlement processes, the primary role of moist environments at near-threshold levels is shown to involve a contribution from enhanced crack closure due to the formation of crack surface corrosion deposits at low load ratios.

  1. Preoperative physical therapy treatment did not influence postoperative pain and disability outcomes in patients undergoing shoulder arthroscopy: a prospective study

    Directory of Open Access Journals (Sweden)

    Valencia C

    2016-07-01

    Full Text Available Carolina Valencia,1 Rogelio A Coronado,2 Corey B Simon,3,4 Thomas W Wright,5 Michael W Moser,5 Kevin W Farmer,5 Steven Z George3,6,7 1Department of Applied Medicine and Rehabilitation, Indiana State University, Terre Haute, IN, 2Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN, 3Department of Physical Therapy, College of Public Health and Health Professions, University of Florida, Gainesville, FL, 4Department of Community Dentistry and Behavioral Science, College of Dentistry, University of Florida, Gainesville,FL, 5Department of Orthopaedics and Rehabilitation, University of Florida, Gainesville, FL, 6Center for Pain Research and Behavioral Health, University of Florida, Gainesville, FL, 7Brooks–PHHP Research Collaboration, Jacksonville, FL, USA Background: There is limited literature investigating preoperative physical therapy (pre-op PT treatment on pain intensity and disability after musculoskeletal surgery. The purposes of the present cohort study were to describe patient characteristics for those who had and did not have pre-op PT treatment and determine whether pre-op PT influenced the length of postoperative physical therapy (post-op PT treatment (number of sessions and 3-month and 6-month postsurgical outcomes, such as pain intensity and disability. Patients and methods: A total of 124 patients (mean age =43 years, 81 males with shoulder pain were observed before and after shoulder arthroscopic surgery. Demographic data, medical history, and validated self-report questionnaires were collected preoperatively and at 3 months and 6 months after surgery. Analysis of variance models were performed to identify differences across measures for patients who had pre-op PT treatment and those who did not and to examine outcome differences at 3 months and 6 months. Alpha was set at the 0.05 level for statistical significance. Results: Males had less participation in pre-op PT than females (P=0.01. In

  2. Influence of Ovarian Hormones on Strength Loss in Healthy and Dystrophic Female Mice

    Science.gov (United States)

    Kosir, Allison M.; Mader, Tara L.; Greising, Angela G.; Novotny, Susan A.; Baltgalvis, Kristen A.; Lowe, Dawn A.

    2014-01-01

    Purpose The primary objective of this study was to determine if strength loss and recovery following eccentric contractions is impaired in healthy and dystrophic female mice with low levels of ovarian hormones. Methods Female C57BL/6 (wildtype) or mdx mice were randomly assigned to ovarian-intact (Sham) and ovariectomized (Ovx) groups. Anterior crural muscles were tested for susceptibility to injury from 150 or 50 eccentric contractions in wildtype and mdx mice, respectively. An additional experiment challenged mdx mice with a 2-wk treadmill running protocol followed by an eccentric contraction injury to posterior crural muscles. Functional recovery from injury was evaluated in wildtype mice by measuring isometric torque 3, 7, 14, or 21 days following injury. Results Ovarian hormone deficiency in wildtype mice did not impact susceptibility to injury as the ~50% isometric torque loss following eccentric contractions did not differ between Sham and Ovx mice (p=0.121). Similarly in mdx mice, hormone deficiency did not affect percent of pre injury isometric torque lost by anterior crural muscles following eccentric contractions (p=0.952), but the percent of pre injury torque in posterior crural muscles was lower in Ovx compared to Sham mice (p=0.014). Recovery from injury in wildtype mice was affected by hormone deficiency. Sham mice recovered pre injury isometric strength by 14 days (96 ± 2%) while Ovx mice maintained deficits at 14 and 21 days post injury (80 ± 3% and 84 ± 2%; phormone status did not impact the vulnerability of skeletal muscle to strength loss following eccentric contractions. However, ovarian hormone deficiency did impair the recovery of muscle strength in female mice. PMID:25255128

  3. Influence of storage times on bond strength of resin cements to root canal

    Directory of Open Access Journals (Sweden)

    Matheus Coêlho Bandéca

    2010-03-01

    Full Text Available The resin cements are responsible to retention of the indirect materials decreasing marginal leakage, increasing failure resistance compared with conventional cementation. The cementation within root canal is very hard due unfavorable conditions regarding the application of adhesive techniques caused by inadequate access. Therefore, considering the possibility to decrease steps of cementation, this study was performed to evaluate the bond strength of self-adhesive resin cement (RelyX TM U100, 3M ESPE and resin cement combined with self-ecthing adhesive system (Panavia® F 2.0, Kuraray light-cured with Quartz Tungsten Halogen (QTH following storage at 37 °C immediately after light-curing, 24 and 48 hours and 7 days. The root canals were prepared to receive the glass fiber post in the depth of 10 mm, irrigated with 17% EDTA and NaOCl, rinsed with distilled water and dried using paper points. The roots were perpendicularly sectioned into approximately 1 mm thick sections, obtaining ninety-six slices (n = 12. The slices were trimmed using a cylindrical diamond bur in the proximal surfaces until it touched the post and attached into a device, which were mounted on a strength tester (Bisco and loaded in tension at a speed of 0.5 mm/min until failure occurred at specimens. The analysis of variance (ANOVA and Tukey's post-hoc tests showed significant statistical differences (P .05. The resin cements 24 and 48 hours after light-curing were statistically similar among themselves (P > .05. The both resin cement showed similar bond strength into root canal on different storage times. The highest bond strength values of the resin cements were showed 7 days after curing.

  4. Impaired hip muscle strength in patients with femoroacetabular impingement syndrome.

    Science.gov (United States)

    Kierkegaard, Signe; Mechlenburg, Inger; Lund, Bent; Søballe, Kjeld; Dalgas, Ulrik

    2017-12-01

    Patients with femoroacetabular impingement (FAI) experience hip pain as well as decreased function and lowered quality of life. The aim was to compare maximal isometric and isokinetic muscle strength (MVC) during hip flexion and extension and rate of force development (RFD) during extension between patients with FAI and a matched reference group. Secondary, the aim was to compare patient hips and subgroups defined by gender and age as well as to investigate associations between hip muscle strength and self-reported outcomes. Design Cross-sectional, comparative study Methods Sixty patients (36±9 years, 63% females) and 30 age and gender matched reference persons underwent MVC tests in an isokinetic dynamometer. During hip flexion and extension, patients' affected hip showed a strength deficit of 15-21% (phip of the patients was significantly weaker than their contralateral hip. RFD was significantly decreased for both patient hips compared to the reference group (phip muscle strength. Patients with FAI demonstrate decreased hip flexion and extension strength when compared to (1) reference persons and (2) their contralateral hip. There seems to be a gender specific affection which should be investigated further and addressed when planning training protocols. Furthermore, self-reported measures were associated with isometric muscle strength, which underlines the clinical importance of the reduced muscle strength. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  5. A comparison of Aboriginal and non-Aboriginal students on the inter-related dimensions of self-concept, strengths and achievement

    Directory of Open Access Journals (Sweden)

    Jessica Whitley

    2014-10-01

    Full Text Available Self-concept has been found to play a key role in academic and psychosocial outcomes for students. Appreciating the factors that have a bearing upon self-concept may be of particular importance for Aboriginal students, many of whom experience poorer outcomes than non-Aboriginal Canadians. The current study explored the relationships between multidimensional self-concept, perceived strengths and academic achievement among a sample Aboriginal and non-Aboriginal students. Results indicated that perceived self-concept and strengths were largely similar across groups. However, students in the two groups drew on different strengths to comprise their general self-concept. Findings are explored within the context of existing research and theory.

  6. Influence of uncoated and coated plastic waste coarse aggregates to concrete compressive strength

    Directory of Open Access Journals (Sweden)

    Purnomo Heru

    2017-01-01

    Full Text Available The use of plastic waste as coarse aggregates in concrete is part of efforts to reduce environmental pollution. In one hand the use of plastic as aggregates can provide lighter weight of the concrete than concrete using natural aggregates, but on the other hand bond between plastic coarse aggregates and hard matrix give low concrete compressive strength. Improvement of the bond between plastic coarse aggregate and hard matrix through a sand coating to plastic coarse aggregate whole surface is studied. Sand used to coat the plastic aggregates are Merapi volcanic sand which are taken in Magelang. Three mixtures of polypropylene (PP coarse plastic aggregates, Cimangkok river sand as fine aggregates, water and Portland Cement Composite with a water-cement ratio of 0.28, 0.3 and 0.35 are conducted. Compression test are performed on concrete cylindrical specimens with a diameter of 10 cm and a height of 20 cm. The results in general show that concrete specimens using plastic aggregates coated with sand have higher compressive strength compared to those of concrete specimens using plastic aggregates without sand coating. The bond improvement is indirectly indicated by the betterment of concrete compressive strength.

  7. Argument Strength and the Persuasiveness of Stories

    Science.gov (United States)

    Schreiner, Constanze; Appel, Markus; Isberner, Maj-Britt; Richter, Tobias

    2017-01-01

    ABSTRACT Stories are a powerful means to change people’s attitudes and beliefs. The aim of the current work was to shed light on the role of argument strength (argument quality) in narrative persuasion. The present study examined the influence of strong versus weak arguments on attitudes in a low or high narrative context. Moreover, baseline attitudes, interindividual differences in working memory capacity, and recipients’ transportation were examined. Stories with strong arguments were more persuasive than stories with weak arguments. This main effect was qualified by a two-way interaction with baseline attitude, revealing that argument strength had a greater impact on individuals who initially were particularly doubtful toward the story claim. Furthermore, we identified a three-way interaction showing that argument strength mattered most for recipients who were deeply transported into the story world in stories that followed a typical narrative structure. These findings provide an important specification of narrative persuasion theory. PMID:29805322

  8. HORMONE REPLACEMENT AND STRENGTH TRAINING POSITIVELY INFLUENCE BALANCE DURING GAIT IN POST-MENOPAUSAL FEMALES: A PILOT STUDY

    Directory of Open Access Journals (Sweden)

    Stephen D. Perry

    2005-12-01

    Full Text Available This study examined the effects of hormone replacement combined with strength training on improving dynamic balance control in post-menopausal women. Thirty one participating post-menopausal women were divided into three groups (hormone replacement (HR, non-hormone replacement (NR and control (CR group. HR and NR groups were tested for muscle strength and balance control during gait, prior to training and following a six week lower body strength training program. Quadriceps muscle strength was evaluated as isokinetic peak torque (60°·sec-1 using a CYBEX NORM and balance control was evaluated by center of mass - base of support relationships and ground reaction forces during gait perturbations. Only the HR group showed significantly (p < 0.05 improved balance control during the initial phase of unexpected gait termination and single stance periods while walking across uneven terrain following training. The strength gains in the HR group tended to be greater than in the NR group over the six week training program, although neither group showed statistically significant increases. The CR group showed no significant differences between testing times. HR in post-menopausal females may enhance dynamic balance control when combined with a strength training program, even if no statistically significant gains in strength are achieved

  9. The effect of the presence and characteristics of an outlying group on exposure-outcome associations.

    Science.gov (United States)

    Coenen, Pieter; Mathiassen, Svend Erik; Kingma, Idsart; Boot, Cécile R L; Bongers, Paulien M; van Dieën, Jaap H

    2015-01-01

    Physical exposures (eg, lifting or bending) are believed to be risk factors for low-back pain (LBP), but the literature is inconsistent. Exposure and LBP prevalence differ considerably between occupations, and exposure-outcome associations could be severely modified by the presence of particular occupational groups. We aimed to investigate the influence of such outlying groups on the properties of associations between exposure and LBP. Lifting and trunk flexion were observed for 371 of 1131 workers within 19 groups. LBP was obtained from all workers during three follow-up years. Both exposure variables were associated with LBP (Pexposures and LBP prevalence substantially affected the exposure-outcome association in the total population. In order to further examine this phenomenon, we assessed, by simulation, the influence of realistic sizes (n=4, 8, 16, 32, 64, 128), mean exposures (e=2000, 3000, 4000 lifts and e=30, 40, 50% trunk flexion time) and LBP prevalences (p=70, 80, 90, 100%) of the outlying group on the strength and certainty of the eventual relationship between exposure and LBP. For each combination of n, e and p, 3000 virtual studies were constructed, including the simulated group together with the other 18 original groups from the parent data-set. Average odds ratios (OR), 95% confidence limits, and power (Pexposure. The size and characteristics of a single group with high exposure and outcome prevalence can strongly influence both the OR point estimate and the likelihood of obtaining significant exposure-outcome associations in studies of large populations. These findings can guide interpretations of prior epidemiological studies and support informed design of future studies.

  10. Evaluation of microtensile and tensile bond strength tests ...

    African Journals Online (AJOL)

    Objectives: The aim of the present study was to compare two different bond strength test methods (tensile and microtensile) in investing the influence of erbium, chromium: yttrium‑scandium‑gallium‑garnet (Er, Cr: YSGG) laser pulse frequency on resin‑enamel bonding. Materials and Methods: One‑hundred and twenty‑five ...

  11. Influence of EDC on Dentin-Resin Shear Bond Strength and Demineralized Dentin Thermal Properties

    Directory of Open Access Journals (Sweden)

    Lin Tang

    2016-11-01

    Full Text Available This study aimed to evaluate the bonding strength and thermal properties of demineralized dentin with and without EDC treatment. Sound human molars were randomly divided into seven treatment groups (n = 20: control, 80% ethanol, and five EDC ethanol solutions (0.01–1.0 M. In each group, 16 samples were used for bond strength assessment and 4 samples were used for scanning electron microscopy (SEM analysis. A further 70 intact molars were used to obtain a fine demineralized dentin powder, treated with the same solutions and were evaluated the crosslink degree by ninhydrin test and denaturation temperature (Td by differential scanning calorimetry. EDC-treated specimens (<1.0 M had a higher bond strength, especially 0.3 and 0.5 M group, than the control counterpart. There was a significant drop in bond strength of 1.0 M EDC group. SEM revealed a homogeneous and regular interface under all treatments. EDC treatment significantly increased the demineralized dentin cross-link degree and Td compared with the control and ethanol treatments. The 0.3 and 0.5 M treatments showed the highest cross-link degree and Td. In terms of mechnical and theramal properties consideration, 0.3 and 0.5 M EDC solutions may be favorable for when applied with etch-and-rinse adhesives, but it is still needed further long-term study.

  12. Functional Capacity in Adults With Cerebral Palsy: Lower Limb Muscle Strength Matters.

    Science.gov (United States)

    Gillett, Jarred G; Lichtwark, Glen A; Boyd, Roslyn N; Barber, Lee A

    2018-05-01

    To investigate the relation between lower limb muscle strength, passive muscle properties, and functional capacity outcomes in adults with cerebral palsy (CP). Cross-sectional study. Tertiary institution biomechanics laboratory. Adults with spastic-type CP (N=33; mean age, 25y; range, 15-51y; mean body mass, 70.15±21.35kg) who were either Gross Motor Function Classification System (GMFCS) level I (n=20) or level II (n=13). Not applicable. Six-minute walk test (6MWT) distance (m), lateral step-up (LSU) test performance (total repetitions), timed up-stairs (TUS) performance (s), maximum voluntary isometric strength of plantar flexors (PF) and dorsiflexors (DF) (Nm.kg -1 ), and passive ankle joint and muscle stiffness. Maximum isometric PF strength independently explained 61% of variance in 6MWT performance, 57% of variance in LSU test performance, and 50% of variance in TUS test performance. GMFCS level was significantly and independently related to all 3 functional capacity outcomes, and age was retained as a significant independent predictor of LSU and TUS test performance. Passive medial gastrocnemius muscle fascicle stiffness and ankle joint stiffness were not significantly related to functional capacity measures in any of the multiple regression models. Low isometric PF strength was the most important independent variable related to distance walked on the 6MWT, fewer repetitions on the LSU test, and slower TUS test performance. These findings suggest lower isometric muscle strength contributes to the decline in functional capacity in adults with CP. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  13. Anelasticity and strength in zirconia ceramics

    International Nuclear Information System (INIS)

    Matsuzawa, M.; Horibe, S.; Sakai, J.

    2005-01-01

    Non-elastic strain behavior was investigated for several different zirconia ceramics and a possible mechanism for anelasticity was discussed. Anelastic strain was detected in zirconia ceramics irrespective of the crystallographic phase and its productivity depended on the particular kind of dopant additive. It was found that the anelastic properties could be significantly influenced by the level of oxygen vacancy in the matrix, and that the anelastic strain might be produced by a light shift of ionic species. In order to investigate the effect of anelasticity on mechanical properties on zirconia ceramics, the tensile strength was investigated for a wide range of strain rates. The obviously unique strain rate dependence was observed only in the materials having anelastic properties. It was assumed that anelasticity could be efficient at improving the tensile strength. (orig.)

  14. The Influence of Violence Victimization on Sexual Health Behaviors and Outcomes.

    Science.gov (United States)

    Latimer, Jennifer; Fleckman, Julia; Wallace, Maeve; Rountree, Michele; Theall, Katherine

    2017-05-01

    This study examines the implications of a history of personal violence on health and health behaviors. A secondary analysis of cross-sectional data involving adults (n = 214) from a semirural area in southern Louisiana between October 2008 and December 2010 was conducted to ascertain the association between a personal history of violence victimization and indicators of sexual health behaviors and outcomes: communication with sexual partners about HIV status, consistent condom use, and sexually transmitted infection (STI). While violence victimization is widely accepted as a risk factor for high-risk sex behavior, the mechanisms underlying violence victimization's influence on sexual health outcomes remain unclear. Bivariate analyses demonstrated a significant positive association between experience of physical abuse and lifetime history of STI. Surprisingly, respondents reporting lifetime physical violence were more than two times more likely to ask sexual partners about HIV status [odds ratio (OR) for physical attack = 2.23, 95% confidence intervals (CI) = 1.00-4.97; OR for physical injury = 4.60, 95% CI = 1.79-11.85]. Consistent condom use was not significantly associated with violence exposure in adjusted models. There was no evidence that communication with sexual partners mediated the relationship between experiences of violence and condom use. The link between personal history of violence and condom use may be mediated through alternative pathways beyond communication.

  15. The Influence of Cardiac Risk Factor Burden on Cardiac Stress Test Outcomes.

    Science.gov (United States)

    Schrock, Jon W; Li, Morgan; Orazulike, Chidubem; Emerman, Charles L

    2011-06-01

    Chest pain is the most common admission diagnosis for observation unit patients. These patients often undergo cardiac stress testing to further risk stratify for coronary artery disease (CAD). The decision of whom to stress is currently based on clinical judgment. We sought to determine the influence of cardiac risk factor burden on cardiac stress test outcome for patients tested from an observation unit, inpatient or outpatient setting. We performed a retrospective observational cohort study for all patients undergoing stress testing in our institution from June 2006 through July 2007. Cardiac risk factors were collected at the time of stress testing. Risk factors were evaluated in a summative fashion using multivariate regression adjusting for age and known coronary artery disease. The model was tested for goodness of fit and collinearity and the c statistic was calculated using the receiver operating curve. A total of 4026 subjects were included for analysis of which 22% had known CAD. The rates of positive outcome were 89 (12.0%), 95 (12.6%), and 343 (16.9%) for the OU, outpatients, and hospitalized patients respectively. While the odds of a positive test outcome increased for additional cardiac risk factors, ROC curve analysis indicates that simply adding the number of risk factors does not add significant diagnostic value. Hospitalized patients were more likely to have a positive stress test, OR 1.41 (1.10 - 1.81). Our study does not support basing the decision to perform a stress test on the number of cardiac risk factors.

  16. Comorbid Diagnosis of Psychotic Disorders in Borderline Personality Disorder: Prevalence and Influence on Outcome

    Directory of Open Access Journals (Sweden)

    C. W. Slotema

    2018-03-01

    Full Text Available BackgroundA diagnosis of psychotic disorder is traditionally considered incompatible with borderline personality disorder (BPD, even though patients sometimes fulfill the diagnostic criteria for both disorders. How often this happens is barely known, as is the influence of comorbid psychotic disorders on the outcome of BPD. Since studies on isolated auditory verbal hallucinations in patients with BPD indicate that these perceptual symptoms have severe consequences and are associated with suicidal behavior and hospitalization, patients with comorbid psychotic disorders are unlikely to fare better.ObjectiveTo examine the point prevalence of psychotic disorders in patients with BPD, their association with the outcome of BPD, and their predictive value for outcome.MethodsIn a cross-sectional design, 84 female outpatients diagnosed with BPD were interviewed with the aid of the MINI-International Neuropsychiatric Interview to establish the point prevalence of comorbid psychotic and other comorbid disorders. After termination of their treatment at a specialized outpatient clinic, the type of referral was considered to be a “good” outcome when they were referred to their general practitioner or to basic psychiatric care for noncomplex patients, and a “poor” outcome when referred to a specialized psychiatric department or to a psychiatric district team for patients with severe psychiatric disorders.ResultsPsychotic disorders were present in 38% of the patients with BPD. With a prevalence of 20%, psychotic disorder not otherwise specified (NOS was the most common subtype; the least common types were schizophrenia (2%, substance-induced psychotic disorder (2%, and brief psychotic disorder (1%. Among six types of comorbid disorders, only psychotic disorders were associated with a poor outcome; they were also predictors for a poor outcome, along with comorbid mood disorders, eating disorders, and somatoform disorders, as well as the severity of BPD

  17. Brittle-fracture statistics for the determination of the strength of fuel particle coatings

    International Nuclear Information System (INIS)

    Bongartz, K.; Schuster, H.

    1976-04-01

    Two influences on characteristic strength values of brittle materials were investigated: the specimen number which is limited in the laboratory by practical reasons, and the procedure for fitting the Weibull formalism to experimental results. The study was performed with respect to the evaluation of the strength of coatings of HTR-fuel particles. Strength values following Weibull statistics were produced artificially to simulate experimental results. The applicability of four different methods was studied to get best fits of the Weibull parameters to these values. The relation of the scatter of strength values and Weibull parameter to the specimen number is determined. (orig./GSCH) [de

  18. Joint awareness after total knee arthroplasty is affected by pain and quadriceps strength.

    Science.gov (United States)

    Hiyama, Y; Wada, O; Nakakita, S; Mizuno, K

    2016-06-01

    There is a growing interest in the use of patient-reported outcomes to provide a more patient-centered view on treatment. Forgetting the artificial joint can be regarded as the goal in joint arthroplasty. The goals of the study were to describe changes in joint awareness in the artificial joint after total knee arthroplasty (TKA), and to determine which factors among pain, knee range of motion (ROM), quadriceps strength, and functional ability affect joint awareness after TKA. Patients undergoing TKA demonstrate changes in joint awareness and joint awareness is associated with pain, knee ROM, quadriceps strength, and functional ability. This prospective cohort study comprised 63 individuals undergoing TKA, evaluated at 1, 6, and 12 months postoperatively. Outcomes included joint awareness assessed using the Forgotten Joint Score (FJS), pain score, knee ROM, quadriceps strength, and functional ability. Fifty-eight individuals completed all postoperative assessments. All measures except for knee extension ROM improved from 1 to 6 months. However, there were no differences in any measures from 6 to 12 months. FJS was affected most greatly by pain at 1 month and by quadriceps strength at 6 and 12 months. Patients following TKA demonstrate improvements in joint awareness and function within 6 months after surgery, but reach a plateau from 6 to 12 months. Quadriceps strength could contribute to this plateau of joint awareness. Prospective cohort study, IV. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. Assessing the organisational and individual strengths use and deficit improvement amongst sport coaches

    Directory of Open Access Journals (Sweden)

    Frederick W. Stander

    2013-11-01

    Research purpose: To (1 determine whether adapted versions of the Strengths Use and Deficit Improvement Questionnaire (SUDIQ and Utrecht Work Engagement Scale (UWES are valid and reliable, (2 determine the relationship of the SUDIQ dimensions in the nomological net, and (3 test a structural model. Motivation for the study: To gain a better understanding of the outcomes of following a balanced approach within a sport coaching context. Research design, approach and method: A cross-sectional research approach was used. An availability sample (N = 364 of teachers occupying roles as sport coaches from various schools across three provinces in South Africa was used. Structural equation modelling was used to test the factor structures and the structural model. Main findings: The results indicated a valid factor structure for the adapted SUDIQ and UWES. Relationships between the SUDIQ dimensions and job and personal resources were positive and significant. Individual strengths use was the strongest predictor of engagement. Individual deficit improvement and organisational strengths use were also significant predictors. Organisational deficit improvement did not significantly predict engagement. Practical/managerial implications: Evidence suggests the adapted SUDIQ and UWES can be utilised effectively in a sport coaching environment. Organisational strengths use is also important in managing engagement levels of sport coaches. Contribution/value-add: Valid and reliable measures were provided for use in a sport coaching environment. It substantiates the outcomes that can be gained by following a combined approach based on strength and deficit.

  20. Screen-based sedentary behavior and associations with functional strength in 6-15 year-old children in the United States.

    Science.gov (United States)

    Edelson, Lisa R; Mathias, Kevin C; Fulgoni, Victor L; Karagounis, Leonidas G

    2016-02-04

    Physical strength is associated with improved health outcomes in children. Heavier children tend to have lower functional strength and mobility. Physical activity can increase children's strength, but it is unknown how different types of electronic media use impact physical strength. Data from the NHANES National Youth Fitness Survey (NNYFS) from children ages 6-15 were analyzed in this study. Regression models were conducted to determine if screen-based sedentary behaviors (television viewing time, computer/video game time) were associated with strength measures (grip, leg extensions, modified pull-ups, plank) while controlling for potential confounders including child age, sex, BMI z-score, and days per week with 60+ minutes of physical activity. Grip strength and leg extensions divided by body weight were analyzed to provide measures of relative strength together with pull-ups and plank, which require lifting the body. The results from the regression models showed the hypothesized inverse association between TV time and all strength measures. Computer time was only significantly inversely associated with the ability to do one or more pull-ups. This study shows that television viewing, but not computer/videogames, is inversely associated with measures of child strength while controlling for child characteristics and physical activity. These findings suggest that "screen time" may not be a unified construct with respect to strength outcomes and that further exploration of the potential benefits of reducing television time on children's strength and related mobility is needed.

  1. Possible stimuli for strength and power adaptation : acute metabolic responses.

    Science.gov (United States)

    Crewther, Blair; Cronin, John; Keogh, Justin

    2006-01-01

    The metabolic response to resistance exercise, in particular lactic acid or lactate, has a marked influence upon the muscular environment, which may enhance the training stimulus (e.g. motor unit activation, hormones or muscle damage) and thereby contribute to strength and power adaptation. Hypertrophy schemes have resulted in greater lactate responses (%) than neuronal and dynamic power schemes, suggesting possible metabolic-mediated changes in muscle growth. Factors such as age, sex, training experience and nutrition may also influence the lactate responses to resistance exercise and thereafter, muscular adaptation. Although the importance of the mechanical and hormonal stimulus to strength and power adaptation is well recognised, the contribution of the metabolic stimulus is largely unknown. Relatively few studies for example, have examined metabolic change across neuronal and dynamic power schemes, and not withstanding the fact that those mechanisms underpinning muscular adaptation, in relation to the metabolic stimulus, remain highly speculative. Inconsistent findings and methodological limitations within research (e.g. programme design, sampling period, number of samples) make interpretation further difficult. We contend that strength and power research needs to investigate those metabolic mechanisms likely to contribute to weight-training adaptation. Further research is also needed to examine the metabolic responses to different loading schemes, as well as interactions across age, sex and training status, so our understanding of how to optimise strength and power development is improved.

  2. Affect influences feature binding in memory: Trading between richness and strength of memory representations.

    Science.gov (United States)

    Spachtholz, Philipp; Kuhbandner, Christof; Pekrun, Reinhard

    2016-10-01

    Research has shown that long-term memory representations of objects are formed as a natural product of perception even without any intentional memorization. It is not known, however, how rich these representations are in terms of the number of bound object features. In particular, because feature binding rests on resource-limited processes, there may be a context-dependent trade-off between the quantity of stored features and their memory strength. The authors examined whether affective state may bring about such a trade-off. Participants incidentally encoded pictures of real-world objects while experiencing positive or negative affect, and the authors later measured memory for 2 features. Results showed that participants traded between richness and strength of memory representations as a function of affect, with positive affect tuning memory formation toward richness and negative affect tuning memory formation toward strength. These findings demonstrate that memory binding is a flexible process that is modulated by affective state. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  3. The influences of impurity content, tensile strength, and grain size on in-service temper embrittlement of CrMoV steels

    International Nuclear Information System (INIS)

    Cheruvu, N.S.; Seth, B.B.

    1989-01-01

    The influences of impurity levels, grain size, and tensile strength on in-service temper embrittlement of CrMoV steels have been investigated. The samples for this study were taken from steam turbine CrMoV rotors which had operated for 15 to 26 years. The effects of grain size and tensile strength on embrittlement susceptibility were separated by evaluating the embrittlement behavior of two rotor forgings made from the same ingot after an extended step-cooling treatment. Among the residual elements in the steels, only P produces a significant embrittlement. The variation of P and tensile strength has no effect on in-service temper embrittlement susceptibility, as measured by the shift in fracture appearance transition temperature (FATT). However, the prior austenite grain size plays a major role in service embrittlement. The fine grain steels with a grain size of ASTM No. 9 or higher are virtually immune to in-service embrittlement. In steels having duplex grain sizes, embrittlement susceptibility is controlled by the size of coarser grains. For a given steel chemistry, the coarse grain steel is more susceptible to in-service embrittlement, and a decrease in ASTM grain size number from 4 to 0/1 increases the shift in FATT by 61 degrees C (10/10 degrees F). It is demonstrated that long-term service embrittlement can be simulated, except in very coarse grain steels, by using the extended step-cooling treatment. The results of step-cooling studies show that the coarse grain rotor steels take longer time during service to reach a fully embrittled state than the fine grain rotor steels

  4. Shear strength of non-shear reinforced concrete elements

    DEFF Research Database (Denmark)

    Hoang, Cao linh

    1997-01-01

    The paper deals with the plastic shear strength of non shear reinforced T-beams.The influence of an un-reinforced flange on the shear capacity is investigated by considering a failure mechanism involving crack sliding in the web and a kind of membrane action over an effective width of the flange...

  5. The Human Skin Microbiome Associates with the Outcome of and Is Influenced by Bacterial Infection

    OpenAIRE

    van Rensburg, Julia J.; Lin, Huaiying; Gao, Xiang; Toh, Evelyn; Fortney, Kate R.; Ellinger, Sheila; Zwickl, Beth; Janowicz, Diane M.; Katz, Barry P.; Nelson, David E.; Dong, Qunfeng; Spinola, Stanley M.

    2015-01-01

    ABSTRACT The influence of the skin microbiota on host susceptibility to infectious agents is largely unexplored. The skin harbors diverse bacterial species that may promote or antagonize the growth of an invading pathogen. We developed a human infection model for Haemophilus ducreyi in which human volunteers are inoculated on the upper arm. After inoculation, papules form and either spontaneously resolve or progress to pustules. To examine the role of the skin microbiota in the outcome of H. ...

  6. Corium crust strength measurements

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439-4840 (United States)], E-mail: lomperski@anl.gov; Farmer, M.T. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439-4840 (United States)], E-mail: farmer@anl.gov

    2009-11-15

    Corium strength is of interest in the context of a severe reactor accident in which molten core material melts through the reactor vessel and collects on the containment basemat. Some accident management strategies involve pouring water over the melt to solidify it and halt corium/concrete interactions. The effectiveness of this method could be influenced by the strength of the corium crust at the interface between the melt and coolant. A strong, coherent crust anchored to the containment walls could allow the yet-molten corium to fall away from the crust as it erodes the basemat, thereby thermally decoupling the melt from the coolant and sharply reducing the cooling rate. This paper presents a diverse collection of measurements of the mechanical strength of corium. The data is based on load tests of corium samples in three different contexts: (1) small blocks cut from the debris of the large-scale MACE experiments, (2) 30 cm-diameter, 75 kg ingots produced by SSWICS quench tests, and (3) high temperature crusts loaded during large-scale corium/concrete interaction (CCI) tests. In every case the corium consisted of varying proportions of UO{sub 2}, ZrO{sub 2}, and the constituents of concrete to represent a LWR melt at different stages of a molten core/concrete interaction. The collection of data was used to assess the strength and stability of an anchored, plant-scale crust. The results indicate that such a crust is likely to be too weak to support itself above the melt. It is therefore improbable that an anchored crust configuration could persist and the melt become thermally decoupled from the water layer to restrict cooling and prolong an attack of the reactor cavity concrete.

  7. Retrospective Attention Interacts with Stimulus Strength to Shape Working Memory Performance.

    Directory of Open Access Journals (Sweden)

    Theresa Wildegger

    Full Text Available Orienting attention retrospectively to selective contents in working memory (WM influences performance. A separate line of research has shown that stimulus strength shapes perceptual representations. There is little research on how stimulus strength during encoding shapes WM performance, and how effects of retrospective orienting might vary with changes in stimulus strength. We explore these questions in three experiments using a continuous-recall WM task. In Experiment 1 we show that benefits of cueing spatial attention retrospectively during WM maintenance (retrocueing varies according to stimulus contrast during encoding. Retrocueing effects emerge for supraliminal but not sub-threshold stimuli. However, once stimuli are supraliminal, performance is no longer influenced by stimulus contrast. In Experiments 2 and 3 we used a mixture-model approach to examine how different sources of error in WM are affected by contrast and retrocueing. For high-contrast stimuli (Experiment 2, retrocues increased the precision of successfully remembered items. For low-contrast stimuli (Experiment 3, retrocues decreased the probability of mistaking a target with distracters. These results suggest that the processes by which retrospective attentional orienting shape WM performance are dependent on the quality of WM representations, which in turn depends on stimulus strength during encoding.

  8. Influence of Lumbar Lordosis on the Outcome of Decompression Surgery for Lumbar Canal Stenosis.

    Science.gov (United States)

    Chang, Han Soo

    2018-01-01

    Although sagittal spinal balance plays an important role in spinal deformity surgery, its role in decompression surgery for lumbar canal stenosis is not well understood. To investigate the hypothesis that sagittal spinal balance also plays a role in decompression surgery for lumbar canal stenosis, a prospective cohort study analyzing the correlation between preoperative lumbar lordosis and outcome was performed. A cohort of 85 consecutive patients who underwent decompression for lumbar canal stenosis during the period 2007-2011 was analyzed. Standing lumbar x-rays and 36-item short form health survey questionnaires were obtained before and up to 2 years after surgery. Correlations between lumbar lordosis and 2 parameters of the 36-item short form health survey (average physical score and bodily pain score) were statistically analyzed using linear mixed effects models. There was a significant correlation between preoperative lumbar lordosis and the 2 outcome parameters at postoperative, 6-month, 1-year, and 2-year time points. A 10° increase of lumbar lordosis was associated with a 5-point improvement in average physical scores. This correlation was not present in preoperative scores. This study showed that preoperative lumbar lordosis significantly influences the outcome of decompression surgery on lumbar canal stenosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Mechanical properties of Concrete with SAP. Part I: Development of compressive strength

    DEFF Research Database (Denmark)

    Hasholt, Marianne Tange; Jespersen, Morten H. Seneka; Jensen, Ole Mejlhede

    2010-01-01

    The development of mechanical properties has been studied in a test program comprising 15 different concrete mixes with 3 different w/c ratios and different additions of superabsorbent polymers (SAP). The degree of hydration is followed for 15 corresponding paste mixes. This paper concerns...... compressive strength. It shows that results agree well with a model based on the following: 1. Concrete compressive strength is proportional to compressive strength of the paste phase 2. Paste strength depends on gel space ratio, as suggested by Powers 3. The influence of air voids created by SAP...... on compressive strength can be accounted for in the same way as when taking the air content into account in Bolomeys formula. The implication of the model is that at low w/c ratios (w/c SAP additions, SAP increases the compressive strength at later ages (from 3 days after casting and onwards...

  10. Influence of nanoporous structure on mechanical strength of aluminium and aluminium alloy adhesive structural joints

    International Nuclear Information System (INIS)

    Spadaro, C; Dispenza, C; Sunseri, C

    2006-01-01

    The influence of surface treatments on the mechanical strength of adhesive joints was investigated. The attention was focused on AA2024 alloy because it is extensively used in both the automotive and aerospace industries. Adhesive joints fabricated with pure aluminium were also investigated in order to evidence possible differences in the surface features after identical treatments. Before joining with a commercial epoxy adhesive, metal substrates were subjected to different kinds of treatment and the surfaces were characterized by SEM analysis. The formation of a microporous surface in the AA2024 alloy, upon etching and anodizing, is discussed on the basis of the role of the intermetallic particles and their electrochemical behaviour with respect to the aluminium matrix. Moreover, nanostructured porous oxide layers on both type of substrate were also formed, as a consequence of the anodizing process. Differences in their morphologies were revealed as a function of both the applied voltage and the presence of alloying elements. On this basis, an explanation of the different values of fracture energy measured by means of T-peel tests carried out on the corresponding joints was attempted

  11. Variations of fracture toughness and stress-strain curve of cold worked stainless steel and their influence on failure strength of cracked pipe

    International Nuclear Information System (INIS)

    Kamaya, Masayuki

    2016-01-01

    In order to assess failure probability of cracked components, it is important to know the variations of the material properties and their influence on the failure load assessment. In this study, variations of the fracture toughness and stress-strain curve were investigated for cold worked stainless steel. The variations of the 0.2% proof and ultimate strengths obtained using 8 specimens of 20% cold worked stainless steel (CW20) were 77 MPa and 81 MPa, respectively. The respective variations were decreased to 13 and 21 MPa for 40% cold worked material (CW40). Namely, the variation in the tensile strength was decreased by hardening. The COVs (coefficients of variation) of fracture toughness were 7.3% and 16.7% for CW20 and CW40, respectively. Namely, the variation in the fracture toughness was increased by hardening. Then, in order to investigate the influence of the variations in the material properties on failure load of a cracked pipe, flaw assessments were performed for a cracked pipe subjected to a global bending load. Using the obtained material properties led to variation in the failure load. The variation in the failure load of the cracked pipe caused by the variation in the stress-strain curve was less than 1.5% for the COV. The variation in the failure load caused by fracture toughness variation was relatively large for CW40, although it was less than 2.0% for the maximum case. It was concluded that the hardening induced by cold working does not cause significant variation in the failure load of cracked stainless steel pipe. (author)

  12. Study on conversion relationships of compressive strength indexes for recycled lightweight aggregate concrete

    Science.gov (United States)

    Zhang, Xiang-gang; Yang, Jian-hui; Kuang, Xiao-mei

    2017-01-01

    In order to study cube compressive strength and axial compressive strength of recycled lightweight aggregate concrete(RLAC), and conversion relationship between the two, with the replacement rate of recycled lightweight coarse aggregate as change parameters, 15 standard cube test specimens and 15 standard prism test specimens were produced to carry out the test. Then compressive strength of test specimens were measured, and the law of different replacement rate of recycled lightweight coarse aggregate influencing compressive strength of RLAC was analyzed, as the method of statistical regression adopted, the conversion relationships between of cube compressive strength and axial compressive strength of RLAC was obtained. It is shown that compressive strength of RLAC are lower than compressive strength of ordinary concrete; and that compressive strength of RLAC gradually decreases as replacement rate of recycled lightweight coarse aggregate increases; as well as, the conversion relationship between axial compressive strength and cube compressive strength of RLAC is different from ordinary concrete; based on the experimental data, conversion relationship formula between compressive strength indexes of RLAC was established. It is suggested that the replacement rate of recycled lightweight aggregate should be controlled within 25%.

  13. The Strength Compass

    DEFF Research Database (Denmark)

    Ledertoug, Mette Marie

    In the Ph.D-project ͚Strengths-based Learning - Children͛s character strengths as a means to their learning potential͛ 750 Danish children have assessed ͚The Strength Compass͛ in order to identify their strengths and to create awareness of strengths. This was followed by a strengths......-based intervention program in order to explore the strengths. Finally different methods to apply the strength in everyday life at school were applied. The paper presentation will show the results for strengths display for children aged 6-16 in different categories: Different age groups: Are the same strengths...... present in both small children and youths? Gender: Do the results show differences between the two genders? Danish as a mother- tongue language: Do the results show any differences in the strengths display when considering different language and cultural backgrounds? Children with Special Needs: Do...

  14. Participatory ergonomics simulation of hospital work systems: The influence of simulation media on simulation outcome

    DEFF Research Database (Denmark)

    Andersen, Simone Nyholm; Broberg, Ole

    2015-01-01

    of tool operation support ergonomics identification and evaluation related to the work system entities space and technologies & tools. The table-top models’ high fidelity of function relations and affordance of a helicopter view support ergonomics identification and evaluation related to the entity......Current application of work system simulation in participatory ergonomics (PE) design includes a variety of different simulation media. However, the actual influence of the media attributes on the simulation outcome has received less attention. This study investigates two simulation media: full......-scale mock-ups and table-top models. The aim is to compare, how the media attributes of fidelity and affordance influence the ergonomics identification and evaluation in PE design of hospital work systems. The results illustrate, how the full-scale mock-ups’ high fidelity of room layout and affordance...

  15. Consequences of Parenting on Adolescent Outcomes

    Directory of Open Access Journals (Sweden)

    Donna Hancock Hoskins

    2014-09-01

    Full Text Available In recent years, substantial gains have been made in our understanding of the influence of parenting behaviors and styles on adolescent emotional and behavioral outcomes. Empirical work focusing on the associations between parenting and adolescent outcomes is important because the influence of parenting during adolescence continues to affect behaviors into adulthood. Additionally, there has been considerable attention paid to the mechanisms that shape parenting that then influence adolescent outcomes. For instance, researchers have found that neighborhood conditions moderated the association between parenting and adolescent development. In this paper, several covariates and contextual effects associated with parenting and adolescent outcomes will be discussed. Also, parental behaviors, parental styles and adolescent outcomes are discussed in this literature review. This review provides an assessment of the literature on parenting and adolescent outcomes from the past decade and includes advancements in parenting research. The review concludes with a summary of major research findings, as well as a consideration of future directions and implications for practice and policy.

  16. Influence of incorporation of ZrO2 nanoparticles on the repair strength of polymethyl methacrylate denture bases

    Directory of Open Access Journals (Sweden)

    Gad MM

    2016-10-01

    Full Text Available Mohammed M Gad,1 Ahmed Rahoma,2,3 Ahmad M Al-Thobity,1 Aws S ArRejaie4 1Department of Substitutive Dental Sciences, 2Department of Restorative Dental Sciences, College of Dentistry, University of Dammam, Dammam, Saudi Arabia; 3Department of Dental Materials, College of Dentistry, Al-Azhar University, Assiut, Egypt; 4Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia Background: Repeated fracture of the denture base is a common problem in prosthodontics, and it represents a nuisance and a time sink for the clinician. Therefore, the possibility of increasing repair strength using new reinforcement materials is of great interest to prosthodontists.Aim of the study: This study aimed to evaluate the effects of incorporation of zirconia nanoparticles (nano-ZrO2 on the flexural strength and impact strength of repaired polymethyl methacrylate (PMMA denture bases.Materials and methods: One hundred eighty specimens of heat-polymerized acrylic resin were fabricated (90 for each test and divided into three main groups: one control group (intact specimens and two groups divided according to surface design (45° bevels and butt joints, in which specimens were prepared in pairs to create 2.5 mm gaps. Nano-ZrO2 was added to repair resin in 2.5 wt%, 5 wt%, and 7.5 wt% concentrations of acrylic powder. A three-point bending test was used to measure flexural strength, and a Charpy-type test was used to measure impact strength. Scanning electron microscopy was used to analyze the fracture surfaces and nano-ZrO2 distribution. The results were analyzed with a paired sample t-test and an unpaired t-test, with a P-value of ≤0.05 being significant.Results: Incorporation of nano-ZrO2 into the repair resin significantly increased flexural strength (P<0.05. The highest value was found in the bevel group reinforced with 7.5% nano-ZrO2, whereas the lowest value was found in the butt group reinforced with 2.5% nano

  17. 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.

  18. [On the influence of D-penicillamine on collage metabolism - investigations of the rupture of strength in tailfibre in rats of several ages (author's transl)].

    Science.gov (United States)

    Trzenschik, K; Lindenhayn, K; Mühlbach, R; Napieralski, P; Noack, K

    1980-01-01

    The tensile strength of rat tail tendons of animals wtih a different age is more influenced by D-Penicillamine (DPA) in younger rats than in elderly rats. DPA has the best effect in the regions with the highest collagen turnover. After the use of DPA the collagen of tails of the elderly rats resembles the collagen of the younger animals. The reason of this alteration is probably a lower degree of cross-links of the collagen after the use of DPA.

  19. The influence of caregiver depression on adolescent mental health outcomes: findings from refugee settlements in Uganda

    OpenAIRE

    Meyer, Sarah R; Steinhaus, Mara; Bangirana, Clare; Onyango-Mangen, Patrick; Stark, Lindsay

    2017-01-01

    Background Family-level predictors, including caregiver depression, are considered important influences on adolescent mental health. Adolescent depression and anxiety in refugee settings is known to be a significant public health concern, yet there is very limited literature from humanitarian settings focusing on the relationship between caregiver mental health and adolescent mental health. In the context of a larger study on child protection outcomes in refugee settings, researchers explored...

  20. Intrinsic rewards, fruit and vegetable consumption, and habit strength: a three-wave study testing the associative-cybernetic model.

    Science.gov (United States)

    Wiedemann, Amelie U; Gardner, Benjamin; Knoll, Nina; Burkert, Silke

    2014-03-01

    Habit formation is thought to lead to long-term maintenance of fruit and vegetable consumption. Habits develop through context-dependent repetition, but additional variables such as intrinsic reward of behaviour may influence habit strength. Drawing upon the Associative-Cybernetic Model, this exploratory study tested different pathways by which intrinsic reward may influence fruit and vegetable consumption habit strength. In a three-wave study of fruit and vegetable intake in adults (N = 127) from the general population, intrinsic reward, intention, and self-efficacy were assessed at baseline, fruit and vegetable consumption and intrinsic reward two weeks later, and habit strength another two weeks later. Direct, indirect, and moderation effects of intrinsic reward on habit strength were tested simultaneously in a moderated mediation model. Intrinsic reward had a positive indirect effect on habit strength through its influence on the frequency of fruit and vegetable consumption. Further, the relationship between fruit and vegetable consumption and habit was stronger where consumption was considered more intrinsically rewarding. Findings highlight the potential relevance of intrinsic reward to habit. We suggest that intrinsic rewards from behaviour may not only facilitate habit via behaviour frequency, but also reinforce the relationship between behavioural repetition and habit strength. © 2013 The International Association of Applied Psychology.