<div>In the past decade, high-strength reinforcement (fy > 60 ksi) has become more prevalent and more widely accepted. Building codes such as ACI 318-14 do not address the use of highstrength reinforcement for proper development and splicing of reinforcement. Furthermore, research on development of high-strength reinforcement is limited. The objective of the study is to develop a suitable expression for the development and splicing of high-strength reinforcement.</div><div>Of particular interest is evaluating the influence of splice length and confinement on bond strength as well as evaluating the effectiveness of high-strength transverse reinforcement on bond strength. The study tested 22 large-scale concrete beams reinforced with ASTM A615</div><div>Grade 100 deformed steel bars: 11 specimens without transverse reinforcement within the splice region (unconfined) and 11 specimens with transverse reinforcement within the splice region (confined). Splice lengths varied from 40 bar diameters to 120 bar diameters, which are some of the largest ever tested. The effect of the test variables which were systematically studied, found</div><div>that splice strength is nonlinearly related with splice length and can be represented by a power equation. Furthermore, it was found that high-strength transverse reinforcement does not improve bond strength compared with the use of Grade 60 transverse reinforcement. Considering the test results and review of historical test results, an analytical investigation was conducted which developed a simple expression for estimating the capacity of both unconfined</div><div>and confined beams. The results are compared with the current building code design expressions as well as other proposed bond strength equations. The research conducted here provides the basis for development of a design expression that will allow for the incorporation of highstrength reinforcement in future building codes.</div>

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta pesquisa estudou a influência de diferentes velocidades de corte e marcas de discos diamantados nos valores de resistência adesiva, durante a preparação dos espécimes a serem submetidos à microtração, e na integridade das amostras por meio do microscópio eletrônico de varredura (MEV). Vinte blocos da cerâmica à base de dissilicato de lítio (IPS e.max Press) foram unidos com cimento resinoso (Rely X ARC) a blocos de compósito (Z100), construídos incrementalmente. Foram seguidas as recomendações dos fabricantes no tratamento da superfície da cerâmica e aplicação do cimento resinoso. Após 24 horas em água destilada a 37C, os espécimes foram divididos em dois grupos de discos: marcas Buehler e Extec e subdivididos nas velocidades de 200rpm e 400rpm (B2; E2; B4 e E4, respectivamente). Cada espécime foi cortado em dois eixos perpendiculares para obtenção de palitos com área adesiva de 1,0mm. Para cada condição experimental, os palitos foram separados, aleatoriamente, 15 palitos para análise ao MEV e 30 palitos para serem submetidos à força de tração. As médias de resistência adesiva em MPa foram E4=20,312 ; B4= 24,2 11,3 ; B2= 25,2 9,0 e E2= 28,6 10,4. Na análise estatística, observou-se que os valores de resistência adesiva na velocidade de 200rpm foram significativamente maiores comparados a velocidade de 400rpm, independente do disco empregado. Ao MEV, observou-se melhor integridade dos palitos na velocidade de 200rpm com presença de trincas menos extensas nas bordas externas. Constatou-se também que o disco Extec na velocidade de 400rpm apresentou movimentos excêntricos ao corte e obteve-se maior número de perdas prematuras, uma diminuição significante na média da área total de união (p<0,05), além de diferença significativa nos valores de resistência comparada a velocidade de 200rpm. Concluiu-se que a utilização de diferentes velocidades e sua interação com o disco empregado interfere na integridade dos espécimes e nos valores de resistência adesiva, sendo mais acentuada ao se utilizar o disco da marca Extec. / The aim of this research was to verify the influence of different cutting speeds and brand of diamond saws during microtensile specimen preparation on the bonding strength values and on the samples microscopy integrity (SEM). Twenty lithium disilicate glass-ceramic blocks (IPS e.max Press) were bonded with dual-cure resin cement (Rely X ARCTM) to composite (Z100TM) blocks, built incrementally. The manufacturers recommendations were followed for ceramic treatment surface and placement on the resin cement, as well. After storage for 24 hours in distillated water at 37C, the specimens were divided in two groups of diamond saws, Buehler and Extec brands, which were further subdivided using 200rpm and 400rpm speeds (B2; E2; B4 and E4 respectively), and they were sectioned into two perpendicular axes obtaining sticks shaped specimens with cross-sectional area of 1.0mm. For each experimental situation the sticks were randomly separated; 15 for the analysis to the SEM and 30 to be submitted to tensile strength. Mean bond strength values (MPa) were: E4 = 20.3 12; B4 = 24.2 11.3; B2 = 25.2 9.0; and E2 = 28.6 10.4. The statistical analysis of data showed that the values of bond strength at 200 rpm speed were significantly higher as compared to 400 rpm speed, regardless of saw employed. In SEM, it was noted better integrity of sticks at 200 rpm speed with presence of less extensive cracks in external edges. It was also found that the Extec saw at 400 rpm showed eccentric movement to cutting and achieved higher number of premature losses, a significant decreased mean total area of bond (p<0.05), in addition to significant difference in strength values compared with 200 rpm speed. It was concluded that using different speeds and their interaction with the used saw interfere with the integrity of specimens and the bond strength values, being more pronounced when using the Extec saw.

Orientador: João Neudenir Arioli Filho / Banca: Sérgio Russi / Banca: Sergio Sualdini Nogueira / Banca: Cláudia Helena Lovato da Silva / Banca: Helena de Freitas Oliveira Paranhos / Resumo: O objetivo deste estudo foi analisar a influência da incorporação de três desinfetantes (hipoclorito de sódio a 1%, glutaraldeído alcalino a 2% e digluconato de clorexidina a 2%) em duas diferentes porcentagens de substituição da água da espatulação (50 e 100%) de dois gessos tipo IV, FujiRock EP (M1) e Rock Plus (M2), avaliando-se a resistência à compressão e à tração diametral. Os corpos-de-prova foram obtidos a partir de matrizes metálicas bipartidas com 20 mm de diâmetro e 40 mm de altura (resistência à compressão) e 20 mm de diâmetro e 10 mm de altura (resistência à tração diametral). As matrizes foram fixadas sobre uma placa de vidro, o gesso foi manipulado na proporção água/pó recomendada pelos fabricantes (M1:20ml/100g e M2:19 ml/100g), em um espatulador mecânico por 30 segundos, e vazado sob vibração. Para cada ensaio foram confeccionados sete grupos para cada gesso (n=10). Os grupos foram: CONTROLE (Água destilada), G50 (substituição de 50% da água de espatulação por glutaraldeído), G100 (100% de glutaraldeído), C50 (substituição de 50% da água por clorexidina), C100 (100% de clorexidina), H50 (substituição de 50% da água por hipoclorito) e H100 (100% de hipoclorito). Após a presa os corpos-de-prova foram removidos das matrizes e armazenados à temperatura ambiente. Os ensaio de compressão e tração diametral foram realizados 24 horas após o vazamento, em uma máquina de ensaios MTS-810, com célula de carga de 100 KN à velocidade de 0,5mm/min. Os valores médios de resistência à compressão e à tração diametral (MPa) foram submetidos à análise de variância e teste de Tukey, com nível de significância de 95%, permitindo concluir que: (a) a incorporação das substâncias desinfetantes estudadas afetou a resistência à compressão de ambos os gessos analisados; (b) as diferentes proporções de incorporação das substâncias... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The purpose of this study was to evaluate the compressive and diametral tensile strength of two Type IV dental stones, FujiRock EP (M1) e Rock Plus (M2), mixed with three disinfectant solutions (sodium hypochlorite 1%, chlorhexidine digluconate 2% and glutaraldehyde 2%) in two different proportions of gauging water (50% and 100%). Compressive samples consisted of cylindrical specimens, each having a diameter of 20 mm and length of 40 mm, and diametral tensile specimens consisted of discshaped specimens, having a diameter of 20 mm and length of 10 mm, obtained from split metal molds. The stone was mixed with the solutions previously outlined at the water-powder ratio recommended by the manufacturers (M1:20ml/100g e M2:19 ml/100g), mechanically spatulated under vacuum (Turbomix) for 30 seconds, and gently vibrated in the molds. Seven groups were prepared for each test, with 10 samples each, as follows: CONTROL (distilled water), G50 (substitution of 50% of gauging water by glutaraldehyde), G100 (only glutaraldehyde), C50 (substitution of 50% of gauging water by chlorhexidine digluconate), C100 (only chlorhexidine digluconate), H50 (substitution of 50% of gauging water by sodium hypochlorite) and H100 (only sodium hypochlorite). Specimens were removed from the molds after they set. Compressive strength and diametral tensile strength was determined 24 hours the specimens were cast, in an MTS-810 testing machine, with a cross-head speed of 0,5mm/min. Mean compressive and diametral tensile strength was calculated and expressed in megapascals (MPa). Data from both tests were analyzed by ANOVA and Tukey test, showing that: (a) chemical disinfectants incorporation reduced the compressive strength of type IV dental stones evaluated; (b) the use of two different proportions of gauging water substitution by disinfectants (50% and 100%) has affected the compressive strength of only one die stone (M1); (c) chemical disinfectants incorporation did not reduced. / Doutor

INTRODUÇÃO: Os efeitos do envelhecimento no sistema respiratório iniciam-se aproximadamente aos 25 anos de idade e leva a diminuição da função máxima deste sistema. Esta diminuição de função é perceptível sobre os volumes e capacidades pulmonar, sobre a força dos músculos respiratórios e do fluxo aéreo, predispondo o idoso a complicações que podem resultar em internações e até em morte. A massa e a força muscular reduzida já é bem estudada nesta população, porém com poucos estudos investigando a relação com a função respiratória. OBJETIVO: Avaliar a relação entre força muscular respiratória e força de preensão palmar em idosos institucionalizados e da comunidade. MÉTODO: Caracteriza-se por um estudo transversal com 64 voluntários, sendo 33 institucionalizado (GI) e 31 da comunidade (GC). Foram avaliados a pressão inspiratória máxima (PImax), pressão expiratória máxima (PEmax), pico de fluxo expiratório (PF), força de preensão palmar dominante (FPP D) e não dominante (FPP ND), dados antropométricos e nível de atividade física (IPAQ curto). Os dados foram submetidos a análise estatística através do teste t student para amostras independentes para comparação entre os grupos, análise de covariância (ANCOVA) controlada pela covariável idade para as variáveis respiratórias e para a força de preensão palmar, teste de Pearson para avaliação da correlação das variáveis e a análise de regressão linear para identificação da influência das variáveis respiratórias sobre a FPP, além da correção de Bonferroni para excluir o erro do tipo I. RESULTADOS: Os valores encontrados nos testes respiratórios e de força entre os grupos, diferiram estatisticamente mesmo controlado pela covariável idade, sendo que o GI apresentou valores inferiores ao GC. No GI não encontramos correlação entre as variáveis respiratórias e as de FPP, porém o preditor respiratório mais fortemente associado à FPP D foi a PEmax (p=0,04). No GC verificou-se correlação entre PImax e FPP D (r=0,539), PEmax e FPP D / ND (r=0,62 / 0,6), PF e FPP D / ND (r=0,64 / 0,43) e o preditor respiratório mais fortemente associado à FPP D foi PF (p=0,009) e PEmax (p=0,028) e para FPP ND foi a PEmax (p=0,021). Na análise conjunta dos grupos verificou-se associação entre PImax e FPP D / ND (r=0,40 / 0,41), PEmax e FPP D / ND (r=0,57 / 0,54), PF e FPP D / ND (r=0,57 / 0,47) e o preditor respiratório mais fortemente associado à FPP D foi PF (p=0,01) e PEmax (p=0,03) e para FPP ND foi a PEmax (p=0,008) e PF (p=0,041). CONCLUSÃO: O GI apresenta maior fraqueza da musculatura respiratória e estas variáveis não se relacionam bem com a FPP. Em idosos da comunidade o PF e a PEmax parecem ser um bom preditor para a FPP / INTRODUCTION: The effects of aging on the respiratory system begin at approximately 25 years of age and lead to a decrease in the maximum function of this system. This diminished function is noticeable on lung volumes and capacities, on respiratory muscle strength and airflow, predisposing the elderly to complications that may result in hospitalization and even death. The mass and reduced muscle strength is already well studied in this population, but with few studies investigating the relation with the respiratory function. OBJECTIVE: To evaluate the relationship between respiratory muscle strength and palmar grip strength in institutionalized and community aged individuals. METHOD: It is characterized by a cross-sectional study with 64 volunteers, being institutionalized 33 (GI) and 31 from the community (GC). The maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), peak expiratory flow (PF), dominant palmar grip strength (FPP D) and non-dominant (FPP ND), anthropometric data and level of physical activity (short IPAQ). The data were submitted to statistical analysis through t Student test for independent samples for comparison between groups, covariance analysis (ANCOVA) controlled by covariate age for respiratory variables and for palmar grip strength, Pearson test for correlation evaluation of the variables and the linear regression analysis to identify the influence of the respiratory variables on the FPP, besides the Bonferroni correction to exclude the type I error. RESULTS: The values found in the respiratory and strength tests between the groups, differed statistically even by the covariable age, and the GI presented values lower than the GC. In GI, we found no correlation between respiratory and FPP variables, but the respiratory predictor most strongly associated with FPP D was the PEmax (p = 0.04). In the CG, correlation was found between PImax and FPP D (r = 0.539), PEmax and FPP D / ND (r = 0.62 / 0.6), PF and FPP D / ND (r = 0.64 / 0, 43) and the respiratory predictor most strongly associated with FPP D was PF (p = 0.009) and PEmax (p = 0.028) and for FPP ND was PEmax (p = 0.021). In the joint analysis of the groups, an association between PImax and FPP D / ND (r = 0.40 / 0,41), PEmax and FPP D / ND (r = 0.57 / 0.54), FP and FPP D (P = 0.01) and PEmax (p = 0.03) and for FPP ND it was the PEmax (p = 0.07) and ND (r = 0.57 / 0.47) and the respiratory predictor most strongly associated with FPP D = 0.008) and PF (p = 0.041). CONCLUSION: GI shows greater respiratory muscle weakness and these variables do not correlate well with PPF. In the elderly in the community, PF and PEmax appear to be a good predictor of PPF

no / A comparison is presented between two indoor localization algorithms using received signal strength, namely the vector algorithm and the Comparative Received Signal Strength (CRSS) algorithm. Signal values were obtained using ray tracing software and processed with MATLAB to ascertain the effects on localization accuracy of radio map resolution, number of access points and operating frequency. The vector algorithm outperforms the CRSS algorithm, which suffers from ambiguity, although that can be reduced by using more access points and a higher operating frequency. Ambiguity is worsened by the addition of more reference points. The vector algorithm performance is enhanced by adding more access points and reference points while it degrades with increasing frequency provided that the statistical mean of error increased to about 60 cm for most studied cases. / Unable to contact publisher. Contact webform only works for members - no email addresses. Raed said he would try and get contact details - email 14th March 2016 / The full text is unavailable. The publisher is unable to be contacted.

The purpose of this dissertation was to examine the existence of force production and strength symmetry while concentrating on its role with performance. Specifically, in this dissertation I sought to determine if differences in symmetry exist between male and female athletes as well as between athletes of different strength levels. Various symmetry assessments were used and the amount of carryover between tests was also evaluated. Furthermore, the relationship between asymmetry magnitude and various aspects of jump performance was also assessed. The results showed that female athletes were more asymmetrical than their male counterparts for most assessments. Interestingly, weaker athletes regardless of gender were more asymmetrical than stronger athletes for all assessments. Symmetry characteristics appeared to carryover between all tests and conditions with the exception of the bilateral strength assessment. When separated by strength level, good carryover of explosive strength symmetry characteristics was noted. A trend of negative relationships was noted between jump performance and kinetic asymmetry, measured during jumps and weight distribution. Isometric mid-thigh pull force production asymmetry did not relate to jump performance as it had previously. Kinetic asymmetry was shown to influence the direction of center of mass displacement (COMd). Specifically, asymmetrical rate of force development showed the most ability to differentiate between values of COMd in the mediolateral direction. The finding that female athletes are more likely to produce force asymmetrically may indicate that they are more susceptible to the performance detriments that accompany force production asymmetry. This may also indicate that female athletes are more susceptible to injury if force asymmetry is an injury predictor. However, differences in asymmetry magnitude between the sexes may be due to differences in strength level between the sexes in the current study, as weaker athletes were shown to be more asymmetrical than their stronger counterparts. Thus, it may be inadequate strength level that is a risk factor to performance detriments and possible injury. It also appears that force production asymmetry can both alter and hinder optimal jump performance. In order to optimize performance and possibly reduce injury risk, it is recommended that weaker athletes focus on bilateral strengthening exercises.

Eight male collegiate weightlifters (age: 21.2 ± 0.9 years; height: 177.6 ± 2.3 cm; and body mass: 85.1 ± 3.3 kg) participated in this study to compare isometric to dynamic force-time dependent variables. Subjects performed the isometric and dynamic mid-thigh clean pulls at 30–120% of their one repetition maximum (1RM) power clean (118.4 ± 5.5 kg) on a 61 X 121.9–cm AMTI forceplate. Variables such as peak force (PF) and peak rate of force development (PRFD) were calculated and were compared between isometric and dynamic conditions. The relationships between force-time dependent variables and vertical jump performances also were examined. The data indicate that the isometric PF had no significant correlations with the dynamic PF against light loads. On the one hand, there was a general trend toward stronger relationships between the isometric and dynamic PF as the external load increased for dynamic muscle actions. On the other hand, the isometric and dynamic PRFD had no significant correlations regardless of the external load used for dynamic testing. In addition, the isometric PF and dynamic PRFD were shown to be strongly correlated with vertical jump performances, whereas the isometric PRFD and dynamic PF had no significant correlations with vertical jump performances. In conclusion, it appears that the isometric and dynamic measures of force-time curve characteristics represent relatively specific qualities, especially when dynamic testing involves small external loads. Additionally, the results suggest that athletes who possess greater isometric maximum strength and dynamic explosive strength tend to be able to jump higher. Eight male collegiate weightlifters (age: 21.2 ± 0.9 years; height: 177.6 ± 2.3 cm; and body mass: 85.1 ± 3.3 kg) participated in this study to compare isometric to dynamic force-time dependent variables. Subjects performed the isometric and dynamic mid-thigh clean pulls at 30–120% of their one repetition maximum (1RM) power clean (118.4 ± 5.5 kg) on a 61 X 121.9–cm AMTI forceplate. Variables such as peak force (PF) and peak rate of force development (PRFD) were calculated and were compared between isometric and dynamic conditions. The relationships between force-time dependent variables and vertical jump performances also were examined. The data indicate that the isometric PF had no significant correlations with the dynamic PF against light loads. On the one hand, there was a general trend toward stronger relationships between the isometric and dynamic PF as the external load increased for dynamic muscle actions. On the other hand, the isometric and dynamic PRFD had no significant correlations regardless of the external load used for dynamic testing. In addition, the isometric PF and dynamic PRFD were shown to be strongly correlated with vertical jump performances, whereas the isometric PRFD and dynamic PF had no significant correlations with vertical jump performances. In conclusion, it appears that the isometric and dynamic measures of force-time curve characteristics represent relatively specific qualities, especially when dynamic testing involves small external loads. Additionally, the results suggest that athletes who possess greater isometric maximum strength and dynamic explosive strength tend to be able to jump higher.

Various body positions have been used in the scientific literature when performing the isometric midthigh pull resulting in divergent results. We evaluated force production in the isometric midthigh pull in bent (125° knee and 125° hip angles) and upright (125° knee, 145° hip angle) positions in subjects with (>6 months) and without (<6 months) substantial experience using weightlifting derivatives. A mixed-design ANOVA was used to evaluate the effect of pull position and weightlifting experience on peak force, force at 50, 90, 200, and 250 ms. There were statistically significant main effects for weightlifting experience and pull position for all variables tested, and statistically significant interaction effects for peak force, allometrically scaled peak force, force at 200 ms, and force at 250 ms. Calculated effect sizes were small to large for all variables in subjects with weightlifting experience, and were small to moderate between positions for all variables in subjects without weightlifting experience. A central finding of the study is that the upright body position (125° knee and 145° hip) should be used given that forces generated are highest in that position. Actual joint angles during maximum effort pulling should be measured to ensure body position is close to the position intended.

Abstract not available

The purpose of this study was to determine the contribution of different in-season strength and power training frequencies to strength and power performance over the course of a 22 week rugby league competition period. Twenty-eight male (n=28) participants, with both high and low strength pre-training status, were divided into three groups following a 15 week pre-season strength and power training programme. A four week periodised in-season strength and power training programme, with intensities ranging from 75-100%, was cycled for the 22 week competition season. Strength and power training was conducted one day.week(-1) by the first high pre-training status group (HTFL, n=11), and two day.week(-1) by the second high pre-training status group (HTF2, n=9). The low pre-training status group (LTF1, n=8) performed the same strength and power training frequency and programme as HTF1. Training intensity (% 1RM) and volume (sets x repetitions) of in-season strength and power training sessions were standardised for both groups during each training week. Strength, power, and speed data were collected pre-season, and four times during the in-season period. No differences were found between HTF1 and HTF2 in performance variables throughout the 22-week in-season period. Both HTF1 and HTF2 displayed similar significant detraining effects in strength, power, and speed, regardless of in-season training frequency (p<0.05). LTF1 showed no change from pre-season strength and power performance following 22 weeks of the competition period (p<0.05). It was concluded that in-season strength and power training frequency may have a limited role in determining the success of the in-season strength and power training programme in highly trained footballers. The results of the present study suggest a number of factors other than in-season strength and power training frequency may affect in-season strength and power performance and detraining in high strength pre-training status athletes. The effect the start of a competition period has on dynamic athletic performance needs further investigation.