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Copyright of Revista Andaluza de Medicina del Deporte is the property of Centro Andaluza de Medicina del Deporte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: To evaluate the effect of distilled water, ethylenediaminetetraacetic acid (EDTA), phosphoric acid and maleic acid on Biodentine regarding surface topography, microhardness and push-out bond strength (POBS).Methods: Fifty-two cylindrical shaped Biodentine specimens were divided into groups: control (distilled water); EDTA (17% EDTA); PA (37% phosphoric acid); and MA (7% maleic acid). Surfaces were evaluated by topographic analysis and Vickers microhardness test. Topographic changes were evaluated qualitatively and microhardness was statistically analyzed by Kruskal-Wallis test. Forty mandibular molars were used to simulate clinical conditions. The crowns were removed and a perforation was created at the furcal floor. The Biodentine was packed into the root perforations and the roots were divided into four groups (DW, EDTA, PA, MA). Samples were stored and subjected to interfacial analysis. POBS data were analyzed by Kruskal-Wallis and Dunn tests.Results: Ethylenediaminetetraacetic acid, MA and PA changed the morphology of the Biodentine surface. PA showed microhardness similar to distilled water (P > 0.05), while MA and EDTA demonstrated reduced values when compared with PA (P < 0.05). PA improved the POBS of Biodentine in comparison with the control.Conclusions: Changes in the topography, microhardness and POBS of Biodentine are associated with irrigant agent used. [ABSTRACT FROM AUTHOR]

Summary: Purpose: Quadriceps strength and patellar tendon (PT) are directly linked and intimately related to daily activities and lower limb function. However, the correlation between knee extension torque (KT) and PT Young's modulus (E) measured directly is still unknown. Method: We used supersonic shearwave imaging (SSI) to evaluate the elastic property of PT in healthy young men and analysed its correlation with KT. Twenty‐two healthy young males were included and both knees were examined. The E of the PT in the dominant and non‐dominant legs was assessed by SSI elastography. KT in maximal voluntary isometric contraction was measured with an isokinetic dynamometer. Result: No correlations between KT and PT E were observed in dominant or non‐dominant side (P = 0·458 and 0·126, respectively). No significant differences in KT or PT E were observed between both legs (P = 0·096 and 0·722, respectively). Intra‐day ICC was rated good (D1 – 0·886, P<0·001 and 0·88, P<0·001) and excellent (D2 – 0·928, P<0·001 and 0·900, P<0·001) for both legs. Inter‐day ICC was rated moderate for both legs (0·651, P = 0·016 and 0·630, P = 0·018, respectively). Conclusion: No significant correlations were found between KT and PT E, suggesting that quadriceps strength is not an accurate predictor for PT mechanical properties in subjects with no specific training engagement. Habitual loading pattern can play a determinant role in PT mechanical properties, regardless of quadriceps strength. Further investigation on SSI acquisition protocols should be conducted to guarantee higher inter‐day ICC values. [ABSTRACT FROM AUTHOR]

Copyright of Revista Andaluza de Medicina del Deporte is the property of Centro Andaluza de Medicina del Deporte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study evaluated the effect of ischemic preconditioning (IPC) on resistance exercise performance in upper limbs. After 12-RM load determination, 21 men attended 4 trials separated by 3 days in a randomized crossover design: IPC (4 x 5-min occlusion 220 mmHg/reperfusion 0 mmHg) in arms and in thighs, and SHAM (equal to the IPC protocol but "occlusion" at 20 mmHg) in arms and in thighs. 8 min following the respective interventions, the subjects performed one set of resistance exercise in elbow flexion with the 12-RM load until concentric failure. The number of repetitions increased for both protocols in arm (IPC = 14.1 ± 2.5 and SHAM = 14.4 ± 3.0) and in thigh (IPC = 14.3 ± 2.2 and SHAM = 13.4 ± 1.7). However, the number of repetitions tended to decrease over the 4 trials and no more effect was found in the fourth trial. Therefore, IPC or SHAM may enhance performance in resistance exercise for upper limbs, but this effect apparently fades over time. [ABSTRACT FROM AUTHOR]

In an effort to detail the thermal variation of the bitumen microstructure, one sample of asphalt cement (CAP 30/45) was analyzed by atomic force microscopy before and after thermal treatment. Phase contrast and topography images showed that sample morphology is highly dependent on the thermal history of the sample. It can be observed that thermal treatment can lead either to asphaltene flocculation or to wax crystallization. In situ measurements indicated that, after thermal cycles, “bees” appear to be immersed in a lamellar structure that resembles a surface crystallization process. Conditions for the crystallization of the waxes as well as the stability of the “bee” are discussed. [ABSTRACT FROM PUBLISHER]

Aim To evaluate the effect of several final irrigants on the adhesion force (Fad) between dentine and resin-based sealers by means of atomic force microscopy (AFM). Methodology Twelve distal roots of mandibular molars were used. The roots were smoothened and cut to obtain 36 specimens. During chemomechanical preparation of the root canals, 5.25% NaOCl was used as the irrigant. The specimens were then divided into six groups according to the final irrigant used: control group - immersed in distilled water (DW) for 1 min; chlorhexidine (CHX) group - in 2% CHX for 1 min; NaOCl group - in 5.25% NaOCl for 1 min; EDTA group - in 17% EDTA for 5 min, EDTA/CHX group - in EDTA, followed by intermediate flushing with DW and then immersed in CHX; EDTA/NaOCl group - in EDTA, followed by intermediate flushing with DW and then immersed in NaOCl. After the treatments, all groups were washed with DW to remove all traces of the irrigants. Afterwards, the samples were dried and attached to a glass base. AFM tips containing AH Plus and Real Seal SE sealers were used to obtain force-distance curves with regard to dentine-treated surfaces. Data were analysed statistically using nonparametric tests with the significance level set at P < 0.05. Results In the groups with smear layer, a final flush with CHX and NaOCl resulted in significantly higher Fad values than the control group for both sealers (P < 0.001). When smear layer was removed, the highest Fad values associated with AH Plus occurred with a final flush of NaOCl, whilst in Real Seal SE, the highest values were found with a final flush of CHX (all results significant at P < 0.001). Conclusion Irrigants had a positive effect on the adhesion of the resin-based sealers, AH Plus and Real Seal SE, to dentine. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the postexercise hypotensive response after different rest intervals between sets (1 and 2 minutes) in normotense older men. Seventeen older men (67.6 ± 2.2 years) with at least 1 year of strength training experience participated. After determination of 10 repetition maximum (10RM) loads for exercises, subjects performed 2 different strength training sessions. On the first day, volunteers performed 3 sets of 10 repetitions per exercise at 70% 10RM, with 1 or 2 minutes' rest interval between sets depending on random assignment. On the second day, the procedures were similar but with the other rest interval. There was no difference in systolic and diastolic blood pressure between rest intervals at any time point measure. Before 1- and 2-minute sessions, the systolic blood pressure values were 122.7 ± 6.0 and 123.2 ± 3.7 mm Hg, and diastolic blood pressure values were 80.5 ± 5.6 and 82.0 ± 3.7 mm Hg, respectively. Both 1 and 2 minute sessions still presented reduced values for systolic blood pressure after 60 minutes (102.9 ± 6.9 and 106.7 ± 5.4 mm Hg, respectively), while the diastolic blood pressure presented significant reductions for 50 minutes after a 1 minute session (12.1 to 5.6 mm Hg) and for 60 minutes after the 2 minute session (13.3 to 6.5 mm Hg). Additionally, the systolic and diastolic blood pressure effect size data demonstrated higher magnitudes at all time point measures after the 2-minute rest sessions. These results suggest a poststrength training hypotensive response for both training sessions in normotense older men, with higher magnitudes for the 2-minute rest session. Our findings suggest a potentially positive health benefit of strength training. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the influence of exercise order on strength and muscle volume (MV) after 12 weeks of nonlinear periodized resistance training. The participants were randomly assigned into 3 groups. One group began performing large muscle group exercises and progressed to small muscle group exercises (LG-SM), whereas another group started with small muscle group exercises and advanced to large muscle group exercises (SM-LG). The exercise order for LG-SM was bench press (BP), machine lat pull-down (LPD), triceps extension (TE), and biceps curl (BC). The order for the SM-LG was BC, TE, LPD, and BP. The third group did not exercise and served as a control group (CG). Training frequency was 2 sessions per week with at least 72 hours of rest between sessions. Muscle volume was assessed at baseline and after 6 weeks and 12 weeks of training by ultrasound techniques. One repetition maximum strength for all exercises was assessed at baseline and after 12 weeks of training. Effect size data demonstrated that differences in strength and MV were exhibited based on exercise order. Both training groups demonstrated greater strength improvements than the CG, but only BP strength increased to a greater magnitude in the LG-SM group as compared with the SM-LG. In all other strength measures (LPD, TE, and BC), the SM-LG group showed significantly greater strength increases. Triceps MV increased in the SM-LG group; however, biceps MV did not differ significantly between the training groups. In conclusion, if an exercise is important for the training goals of a program, then it should be placed at the beginning of the training session, regardless of whether or not it is a large muscle group exercise or a small muscle group exercise. [ABSTRACT FROM AUTHOR]

It is speculated that exercise training decreases resting levels of tumor necrosis factor alpha (TNF-a) and C-reactive protein (CRP); reduces body mass and leptin (LP); and increases adi-' ponectin (AD) and insulin sensitivity. This systematic review analyzed the effectiveness of resistance training (RI) longitudinal clinical studies on AD, LP, CRP and TNF-a. Seventeen studies were included and the majority of randomized controlled trials support that RT produces increases in AD, and decreases in both LP and CRP. Greater responses in AD and LP were evident in overweight and obese individuals; while RT appeared to be effective in reducing CRP in obese individuals, and older adults. Additionally, women may be more responsive to RT effects on AD, LP and CRP. Training duration and intensity may affect the response of AD and CRP with greater responses shown with 16 weeks or more of training and/or with intensities greater than 80% of one repetition maximum. No response to RT of TNF-a levels was apparent. Although based on a limited number of studies, some of which are uncontrolled non-randomized in design, our review suggests some positive effects of RT programs on cytokine levels, but specifics of the responses in different populations need further elucidation. [ABSTRACT FROM AUTHOR]

Bitumen is a complex mixture of hydrocarbons for which microstructural understanding is incomplete. In an effort to detail this microstructure, a asphalt cement sample (CAP 30/45) was analysed by thermal phase detection atomic force microscopy. Phase contrast and topography images showed that sample morphology is highly dependent on temperature. The ‘bee structure’ changed considerably at temperatures between 50°C and 56°C. A decrease of the oscillation amplitude was observed upon heating and the ‘bees’ completely disappeared at temperatures above 57°C. When the temperature was decreased after melting at 170°C, the ‘bees’ began to nucleate gradually at temperatures of 57°C and its evolution with time was followed. Changes in morphology were compared to thermal analysis results and a model for the ‘bee’ structure was proposed. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the cardiovascular effects of anabolic androgenic steroid (AAS) use, specifically the hemodynamic response, during maximal treadmill exercise testing by comparing the exercise response between users of AAS (U-AAS) and non-AAS users (N-AAS). Twenty-four men (n=12; 29+/-3.4 years and n=12; 29.5+/-8.2 years for the U-AAS and N-AAS groups, respectively) with regular participation in both resistance (mean=6 d.wk) and aerobic exercise (mean=2 d.wk) volunteered for the study. Both groups of subjects completed a ramp-protocol maximal treadmill exercise test to volitional fatigue. Several hemodynamic and metabolic measures were obtained before, during, and after testing. The results demonstrate for the first time that chronic administration of high doses of AAS (355.4+/-59.47 mg.wk) lead to hemodynamic and metabolic response impairment. In conclusion, the chronotropic significant incompetence in the current study was reflected by an exaggerated hemodynamic response to exercise. Furthermore, the findings suggest that nonusers of AAS showed increases in VO2max when compared to the AAS group. Therefore, this study provides a contraindication to AAS use, especially in those at increased risk of cardiovascular events. [ABSTRACT FROM AUTHOR]

There are several equations to predict maximum oxygen consumption (VO2max) from ergometric test variables on different ergometers. However, a similar equation using ventilatory thresholds of ergospirometry in a submaximal test on a cycle ergometer is unavailable. The aim of the present study was to assess the accuracy of VO2max prediction models based on indicators of submaximal effort. Accordingly, 4,640 healthy, nonathlete women ages 20 years and older volunteered to be tested on a cycle ergometer using a maximum incremental protocol. The subjects were randomly assigned to 2 groups: group A (estimation) and group B (validation). From the independent variables of weight in kilograms, the second workload threshold (WT2), and heart rate of the second threshold (HRT2), it was possible to build a multiple linear regression model to predict maximal oxygen consumption (VO2max = 40.302 - 0.497 [Weight] - 0.001 [HRT2] + 0.239 [WT2] in mL O2/kg/min(-1); r = 0.995 and standard error of the estimate [SEE] = 0.68 mL O2/kg/min(-1)). The cross-validation method was used in group B with group A serving as the basis for building the model and the validation dataset. The results showed that, in healthy nonathlete women, it is possible to predict VO2max with a minimum of error (SEE = 1.00%) from submaximal indicators obtained in an incremental test. [ABSTRACT FROM AUTHOR]

This article presents a morphological, chemical, and fractal dimension study of the time evolution of aluminum AC anodization in 1 M H3PO4 solution. The morphological analysis was accomplished by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). According to SEM, ordered porous pattern was already observed after 90 s of anodization, yet AFM revealed a different surface morphology evolution. Stripes were observed on the surface at the initial stages of anodization, developing to the formation of a complete phosphate layer at an intermediate stage and finally, to a porous structure at the steady stage. The phosphate layer was observed by AFM as well as by Auger Electron Spectroscopy (AES). Nevertheless, it could not be noticed by SEM. AFM data were quantified by fractal dimension and no significant changes in terms of fractal dimension were found in the function of the anodization time. [ABSTRACT FROM AUTHOR]

In order to obtain further information on the structural organization of the cuticle of nematodes, this structure was isolated from adult forms of the filariid Litomosoides chagasfilhoi. The purity of the fraction was determined by light and transmission electron microscopy, deep-etching, high resolution scanning electron microscopy, atomic force microscopy, immunocytochemistry, gel electrophoresis (SDS-PAGE) and Western blot. The epicuticle presented a rugous surface with parallel rows and several globular particles that could be involved in the absorption of nutrients and secretion of products. Analysis by SDS-PAGE of purified cuticles revealed five major polypeptides corresponding to 151, 41, 28, 13 and 11 kDa. A polyclonal antibody against a synthetic 18 amino-acid peptide that corresponds to the sequence of domain E of the Haemonchus contortus 3A3 collagen gene recognized several protein bands on the Western blot of purified cuticle, and labeled all cuticular layers, as shown by immunocytochemistry. [ABSTRACT FROM AUTHOR]

Magnetic force microscopy (MFM) is used to investigate the surface magnetic structure of steels Fe–28Mn–8.5Al–1C–1.4Si under the different regimes of isothermal aging. A theoretical model for the MFM imaging of such structures is developed. Calculation of van der Waals forces is performed in order to interpret the topography images. The lateral resolution in terms of the magnetic field dependence on the surface coordinates is investigated. Finally, conditions that should be fulfilled for a good imaging of the samples are formulated. [ABSTRACT FROM AUTHOR]

Aspergillus tamarii produced extracellular xylanase and intracellular β-xylosidase inductively in washed glucose-grown mycelia incubated with xylan and methyl β- d-xyloside, a synthetic glycoside. Methyl β- d-xyloside was a more effective inducer than xylan at the same concentration for both enzymes. Glucose and cycloheximide were found to inhibit xylanase production by methyl β- d-xyloside. Methyl β- d-xyloside was hydrolyzed to xylose by mycelial extract in vitro. [ABSTRACT FROM AUTHOR]

INTRODUÇÃO: A pandemia fez com que no início de 2020 as atividades desportivas fossem suspensas no Brasil. Esse fato impactou no processo de formação dos jovens atletas de futebol e consequentemente no desenvolvimento das capacidades físicas. É importante destacar que uma partida será caracterizada por ações anaeróbicas intermitentes de alta intensidade e pela boa sustentação de condições aeróbicas, logo é importante o monitoramento dessas capacidades nos atletas. OBJETIVO: Comparar a capacidade cardiorrespiratória (Vo2max) de jovens atletas de futebol no seu retorno às atividades presenciais da modalidade, após passar por um período de suspensão por causa da pandemia, e após três meses desse retorno. MÉTODO: A amostra foi composta por 27 jovens atletas de futebol de um clube de elite (idade: 14,0±0,3 anos; massa corporal: 55,4±9,9 kg; estatura: 167,7±8,8 cm). Como critérios de inclusão: a) ser atleta federado do clube; b) realizar três meses de treinamento específico da modalidade. Para estimar o Vo2max foi utilizado o teste Yo-Yo Intermittent Recovery Test level 1 proposto por Bangsbo et al. (2008). A primeira avaliação foi realizada em abril de 2021 e a segunda em agosto. Na análise estatística, inicialmente foi testada a normalidade pelo teste Kolmogorov- Smirnov e após, foi utilizado o Test T para amostras pareadas. Para todos os testes foi adotado o nível de significância de p<0,05. Para tal foi utilizado o software SPSS versão 20.0. RESULTADOS: O Vo2max encontrado em abril de 2021 foi de 42,3±1,5 ml/min/kg, enquanto o Vo2max aferido em agosto de 2021 foi de 47,2±2,4 ml/min/kg. A partir das análises, encontramos o resultado de agosto como significativamente maior (p<0,05) do que o verificado em abril. Vale destacar que em abril de 2021, os atletas estavam retornando as atividades presenciais e tinham passado por treinamentos que aconteciam de forma irregular e prioritariamente online desde o segundo trimestre de 2020. CONSIDERAÇÕES FINAIS: Foi possível verificar que os atletas conseguiram melhorar o Vo2max em um curto período. Kalinowski et al. (2021) também encontraram um resultado parecido com o nosso. Isso pode ser explicado inicialmente por um resultado abaixo do normal na primeira avaliação, o que provavelmente foi influenciado por todo contexto da pandemia. [ABSTRACT FROM AUTHOR]

Copyright of Revista Andaluza de Medicina del Deporte is the property of Centro Andaluza de Medicina del Deporte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Soccer Science / Revista Brasileira de Futebol is the property of Revista Brasileira de Futebol and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)