oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2020 ( 3 )

2019 ( 97 )

2018 ( 126 )

2017 ( 119 )

Custom range...

Search Results: 1 - 10 of 81505 matches for " Carlos Rafaell Correia-Oliveira "
All listed articles are free for downloading (OA Articles)
Page 1 /81505
Display every page Item
Pacing strategy adopted in crawl swimming competitions: an analysis of the 800-m and 1500-m distances
Mayara Vieira Damasceno,Carlos Rafaell Correia-Oliveira,Thais Narita,Leonardo Alves Pasqua
Revista Brasileira de Cineantropometria e Desempenho Humano , 2013, DOI: http://dx.doi.org/10.5007/1980-0037.2013v15n3p361
Abstract: In long distance swimming competitions, the optimal pacing strategy is not well established. The objective of this study was to characterize the pacing strategy adopted by international level athletes in 800-m (female) and 1500-m (male) crawl swimming events. We analyzed the time of each 50 m splits for semi-finalists and finalists athletes of the last three world swimming championships from 2006 to 2010. The data analysis was performed through the statistic method named CHAID (Chi-Squared Automatic Interaction Detection), which is a statistic χ2 to detect a homogeneity behavior among the variables. The main results found were: for the two events analyzed, the velocity-versus-distance curve was similar to the parabolic pacing strategy (U-shaped), characterized by a significantly faster start (p<0.05) than mean velocity for the race, followed by a gradual decline invelocity in the middle splits, when athletes increase the velocity again (p<0.05) to produce an end spurt. In conclusion, these findings indicate that this pacing strategy profile can be classified as optimal for the long distances wimming events since it was preferentially adopted by international level athletes.
Caffeine Alters Anaerobic Distribution and Pacing during a 4000-m Cycling Time Trial
Ralmony de Alcantara Santos, Maria Augusta Peduti Dal Molin Kiss, Marcos David Silva-Cavalcante, Carlos Rafaell Correia-Oliveira, Romulo Bertuzzi, David John Bishop, Adriano Eduardo Lima-Silva
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0075399
Abstract: The purpose of the present study was to investigate the effects of caffeine ingestion on pacing strategy and energy expenditure during a 4000-m cycling time-trial (TT). Eight recreationally-trained male cyclists volunteered and performed a maximal incremental test and a familiarization test on their first and second visits, respectively. On the third and fourth visits, the participants performed a 4000-m cycling TT after ingesting capsules containing either caffeine (5 mg.kg?1 of body weight, CAF) or cellulose (PLA). The tests were applied in a double-blind, randomized, repeated-measures, cross-over design. When compared to PLA, CAF ingestion increased mean power output [219.1±18.6 vs. 232.8±21.4 W; effect size (ES) = 0.60 (95% CI = 0.05 to 1.16), p = 0.034] and reduced the total time [419±13 vs. 409±12 s; ES = ?0.71 (95% CI = ?0.09 to ?1.13), p = 0.026]. Furthermore, anaerobic contribution during the 2200-, 2400-, and 2600-m intervals was significantly greater in CAF than in PLA (p<0.05). However, the mean anaerobic [64.9±20.1 vs. 57.3±17.5 W] and aerobic [167.9±4.3 vs. 161.8±11.2 W] contributions were similar between conditions (p>0.05). Similarly, there were no significant differences between CAF and PLA for anaerobic work (26363±7361 vs. 23888±6795 J), aerobic work (68709±2118 vs. 67739±3912 J), or total work (95245±8593 vs. 91789±7709 J), respectively. There was no difference for integrated electromyography, blood lactate concentration, heart rate, and ratings of perceived exertion between the conditions. These results suggest that caffeine increases the anaerobic contribution in the middle of the time trial, resulting in enhanced overall performance.
Caffeine Increases Anaerobic Work and Restores Cycling Performance following a Protocol Designed to Lower Endogenous Carbohydrate Availability
Marcos David Silva-Cavalcante, Carlos Rafaell Correia-Oliveira, Ralmony Alcantara Santos, Jo?o Paulo Lopes-Silva, Hessel Marani Lima, Romulo Bertuzzi, Marcos Duarte, David John Bishop, Adriano Eduardo Lima-Silva
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0072025
Abstract: The purpose this study was to examine the effects of caffeine ingestion on performance and energy expenditure (anaerobic and aerobic contribution) during a 4-km cycling time trial (TT) performed after a carbohydrate (CHO) availability-lowering exercise protocol. After preliminary and familiarization trials, seven amateur cyclists performed three 4-km cycling TT in a double-blind, randomized and crossover design. The trials were performed either after no previous exercise (CON), or after a CHO availability-lowering exercise protocol (DEP) performed in the previous evening, followed by either placebo (DEP-PLA) or 5 mg.kg?1 of caffeine intake (DEP-CAF) 1 hour before the trial. Performance was reduced (?2.1%) in DEP-PLA vs CON (421.0±12.3 vs 412.4±9.7 s). However, performance was restored in DEP-CAF (404.6±17.1 s) compared with DEP-PLA, while no differences were found between DEP-CAF and CON. The anaerobic contribution was increased in DEP-CAF compared with both DEP-PLA and CON (67.4±14.91, 47. 3±14.6 and 55.3±14.0 W, respectively), and this was more pronounced in the first 3 km of the trial. Similarly, total anaerobic work was higher in DEP-CAF than in the other conditions. The integrated electromyographic activity, plasma lactate concentration, oxygen uptake, aerobic contribution and total aerobic work were not different between the conditions. The reduction in performance associated with low CHO availability is reversed with caffeine ingestion due to a higher anaerobic contribution, suggesting that caffeine could access an anaerobic “reserve” that is not used under normal conditions.
Heart rate kinetics during very heavy and severe exercise performed after dietary manipulation. DOI: 10.5007/1980-0037.2011v13n1p52
Carlos Rafaell Correia de Oliveira,Flávio Oliveira Pires,Romulo Cassio Moraes Bertuzzi,Fernando Roberto de Oliveira
Revista Brasileira de Cineantropometria e Desempenho Humano , 2011,
Abstract: Little is known about heart rate (HR) kinetics during exercise in the very heavy (VH) and severe (SE) intensity domains. The objective of this study was to describe mathematically the HR kinetics during exercise performed in these intensity domains and to compare the parameters derived from these models between situations of high (HCHO), low (LCHO) and control (C) carbohydrate availability. Twelve men performed three trials to exhaustion in the VH or SE domains after diet manipulation with HCHO, LCHO and C. The VH intensity was ΔLW75% (75% of the difference between VO2max and LL2) and SE was 115% of VO2max identified in a previous incremental test (20 W/3 min). HR responses were mathematically fitted by mono- and biexponential functions. In the VH domain, the residual sum of squares (RSS) obtained with the biexponential model was significantly lower than that obtained with the monoexponential model (P < 0.05). In the SE domain, no significant difference in RSS was observed between the mathematical models (P > 0.05). In the VH domain, there were no significant differences in biexponential parameters between the HCHO, LCHO and C conditions. In the SE domain, there were no significant differences in monoexponential parameters between the HCHO, LCHO and C conditions, although the time constant of the monoexponential model was significantly reduced in LCHO when compared to HCHO (51.5 ± 26.4 vs 65.4 ± 34.1 s; P < 0.05). The bi- and monoexponential mathematical models seem to be the best description of HR responses during exercise performed in the HV and SE intensity domains, respectively. In addition, carbohydrate availability only seems to affect HR kinetics during exercise performed at SE intensity.
Primeiro registro no Brasil de Erythrina velutina Willd. como hospedeira de Tetranychus neocaledonicus (Acari: Tetranychidae)
Poderoso, J.C.M.;Ribeiro, G.T.;Návia, D.;Passos, E.M.;Gon?alves, G.B.;Correia-Oliveira, M.E.;Dantas, P.C.;
Revista Brasileira de Plantas Medicinais , 2010, DOI: 10.1590/S1516-05722010000300017
Abstract: spider mites are important pests to several crops worldwide. during prospecting in erytrina velutina specimens from s?o cristov?o district, sergipe state, brazil, their occurrence was observed in 15% seedlings, which were taken to the laboratory for description of damages. the seedlings presented leaf blade reduction and crumpling symptoms. one hundred mites were collected from these seedlings and mounted on microscope slides for taxonomic identification. the identified mites belonged to the species tetranychus neocaledonicus (acari: tetranychidae). this is the first report of e. velutina as host for t. neocaledonicus in brazil.
Cinética da frequência cardíaca nos domínios muito pesado e severo após manipula??o dietética
Oliveira, Carlos Rafaell Correia de;Pires, Flávio de Oliveira;Bertuzzi, R?mulo de Cássio Moraes;De-Oliveira, Fernando Roberto;Kiss, Maria Augusta Peduti Dal Molin;Lima-Silva, Adriano Eduardo;
Revista Brasileira de Cineantropometria & Desempenho Humano , 2011, DOI: 10.5007/1980-0037.2011v13n1p52
Abstract: little is known about heart rate (hr) kinetics during exercise in the very heavy (vh) and severe (se) intensity domains. the objective of this study was to describe mathematically the hr kinetics during exercise performed in these intensity domains and to compare the parameters derived from these models between situations of high (hcho), low (lcho) and control (c) carbohydrate availability. twelve men performed three trials to exhaustion in the vh or se domains after diet manipulation with hcho, lcho and c. the vh intensity was ?lw75% (75% of the difference between vo2max and ll2) and se was 115% of vo2max identified in a previous incremental test (20 w/3 min). hr responses were mathematically fitted by mono- and biexponential functions. in the vh domain, the residual sum of squares (rss) obtained with the biexponential model was significantly lower than that obtained with the monoexponential model (p < 0.05). in the se domain, no significant difference in rss was observed between the mathematical models (p > 0.05). in the vh domain, there were no significant differences in biexponential parameters between the hcho, lcho and c conditions. in the se domain, there were no significant differences in monoexponential parameters between the hcho, lcho and c conditions, although the time constant of the monoexponential model was significantly reduced in lcho when compared to hcho (51.5 ± 26.4 vs 65.4 ± 34.1 s; p < 0.05). the bi- and monoexponential mathematical models seem to be the best description of hr responses during exercise performed in the hv and se intensity domains, respectively. in addition, carbohydrate availability only seems to affect hr kinetics during exercise performed at se intensity.
Rela??o entre a cinética do consumo de oxigênio e a estratégia de corrida em uma prova de 10km
Damasceno, Mayara Vieira;Bertuzzi, R?mulo Cássio de Moraes;Pires, Flavio de Oliveira;Oliveira, Carlos Rafaell Correia de;Barros, Ronaldo Vilela;Gagliardi, Jo?o Fernando Laurito;Silva, Thays de Ataíde e;Kiss, Maria Augusta Peduti Dal Molin;Lima-Silva, Adriano Eduardo;
Revista Brasileira de Medicina do Esporte , 2011, DOI: 10.1590/S1517-86922011000500012
Abstract: this study examined the influence of the o2 kinetics on the running strategy adopted during a 10km running race in runners with different performance levels. twenty-one runners (28.5 ± 5.3 years; 17.6 ± 7.3 cm; 66.3 ± 9.3 kg) performed 1) a test with increments of 1.2 km.h-1 every 3 min until exhaustion; 2) one 6-min test of constant velocity at 9 km.h-1 for determination of o2 kinetics and; 3) a 10 km time trial simulation. the subjects were divided into two groups, moderated performance (mp) and low perfomance (lp), based on the 10-km running performance. mean velocity (mp= 16.9 ± 0.8 vs bp= 14.9 ± 1 km.h-1) on the 10km race was significantly different (p<0.05) between groups. there were no differences (p>0.05) between groups in any kinetics parameters analyzed. however, the o2 increase amplitude (a1 parameter) was inversely correlated with mean velocity (r= -0.48, p < 0.05) and with the partial velocities on time trial (r between -0.44 and -0.48, p < 0.05), except for the last session (r=-0.19, p > 0.05). in conclusion, the correlation of a1 parameter with the partial velocities suggests an influence of running economy on the strategy adopted during the 10 km time trial.
Operationalizing Interaction between Firms and Regions  [PDF]
Ricardo Correia, Carlos Brito
Theoretical Economics Letters (TEL) , 2016, DOI: 10.4236/tel.2016.64074
Abstract: Regions are very different as they contain an amalgam of different resources shaped by a diversity of actors. In some extent, they are the result of interactions of different actors that can be located either inside or outside them. Firms are one of the actors that assume more relevance for the regional configuration. Indeed firms have a capacity to act beyond any regional boundaries and a successful firm can “infect” positively the regional dynamics. But the opposite influence is also true. The regional configuration may have impact on the strategic action of firms. The interconnection between firms and territories is thus a key issue for the understanding of the development of both businesses and regions. However, the interactions between firms and regions have not been sufficiently explained. In this context, the purpose of this paper is to clarify the bidirectional influence between firms and regions. Taking advantage of the emerging literature of relational geography and industrial network approach, a model aimed at providing a better understanding of this mutual influence was developed. We find that the lack of relational compatibility can limit firms’ effects on the region. Similarly, the influence of the region on firms’ performance also depends on this compatibility and on the specific characteristics of the business
Rea es de Heck-Matsuda direcionadas pelo substrato: Síntese estereosseletiva de arilciclopentenos
Caio Costa Oliveira,Emerson Andrade Ferreira dos Santos,Carlos Roque Duarte Correia
Orbital : the Electronic Journal of Chemistry , 2012,
Abstract: A rea o de arila o de olefinas catalisada por paládio é conhecida como rea o de Heck-Matsuda [1]. Recentemente nosso grupo demonstrou que durante a arila o de ésteres e amidas alílicas o controle régio e estereoquímico da rea o foi direcionado por estes substratos, que atuaram como ligantes para as espécies cati nicas de paládio [2,3]. Neste contexto, o objetivo deste trabalho foi desenvolver uma metodologia diastereosseletiva para a arila o da olefina cíclica 1 com sais de arenodiaz nio 2. Os adutos de Heck 4 foram obtidos com rendimentos entre 41 e 82% e com excesso diastereomérico entre 70 e 95%. A diferencia o das faces do anel foi realizada pela carbonila do carbamato 3, que é mais rica em elétrons do que a do éster. Esta metodologia foi aplicada em uma síntese curta e eficiente de um agonista seletivo do receptor S1P1 7 utilizado no tratamento da esclerose múltipla [4].
Goldenhar's syndrome: case report
Pinheiro, Ant?nio Luiz Barbosa;Araújo, Luciana Cavalcanti;Oliveira, Suely Baptista;Sampaio, Maria Carmeli Correia;Freitas, André Carlos;
Brazilian Dental Journal , 2003, DOI: 10.1590/S0103-64402003000100013
Abstract: goldenhar's syndrome is a rare condition described initially in the early 1950's. it is characterized by a combination of anomalies: dermal epibulbar cysts, auricular appendices and malformation of the ears. in 1963, gorlin suggested the name oculo-auriculo-vertebral (oav) dysplasia for this condition and also included vertebral anomalies as signs of the syndrome. the etiology of this rare disease is not fully understood, as it has shown itself variable genetically and of unclear causes. this work reports a case of goldenhar's syndrome in an 11-year-old female, who presented all classical signs of this rare condition
Page 1 /81505
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.