Chronic versus acute ingestion of sodium citrate: a randomized placebo controlled cross-over trial for swimming 200 metres in well-trained swimmers age 13-17

A double-blinded, placebo controlled, cross-over design was used to investigate sodium citrate dihydrate (Na-CIT) supplementation improve 200m swimming performance. Ten well-trained, male swimmers (14.9 ± 0.4y; 63.5 ± 4kg) performed four 200m time trials: acute (ACU) supplementation (0.5g/kg), acute placebo (PLC-A), chronic (CHR) (0.1g/kg for 3 days and 0.3g/kg on the 4th day pre-trial), and chronic placebo (PLC-C). Na-CIT was administered 120min pre-trial in solution with 500mL of flavored water; placebo was flavored water. Blood lactate, base excess (BE), bicarbonate, pH, and PCO2 were analyzed at basal, 100min post-ingestion, and 3min post-trial via finger prick. Time, lactate, and rate of perceived exertion were not different between trials. BE and bicarbonate were significantly higher for the ACU and CHR trials compared to placebo. “Responders” improved by 1.03% (P=0.043) and attained significantly higher post-trial lactate concentrations in the ACU versus PLC-A trials and compared to non-responders in the ACU and CHR trials.

The effect of elevated muscle fluid volume on indices of muscle damage following an acute bout of eccentric exercise

The primary purpose of the current investigation was to develop an elevated muscle fluid level using a human in-vivo model. The secondary purpose was to determine if an increased muscle fluid content could alter the acute muscle damage response following a bout of eccentric exercise. Eight healthy, recreationally active males participated in a cross-over design involving two randomly assigned trials. A hydration trial (HYD) consisting of a two hour infusion of a hypotonic (0.45%) saline at a rate of 20mL/minVl .73m"^ and a control trial (CON), separated by four weeks. Following the infusion (HYD) or rest period (CON), participants completed a single leg isokinetic eccentric exercise protocol of the quadriceps, consisting of 10 sets of 10 repetitions with a one minute rest between each set. Muscle biopsies were collected prior to the exercise, immediately following and at three hours post exercise. Muscle analysis included determination of wet-dry ratios and quantification of muscle damage using toluidine blue staining and light microscopy. Blood samples were collected prior to, immediately post, three and 24 hours post exercise to determine changes in creatine kinase (CK), lactate dehydrogenase (LD), interleukin-6 (IL-6) and Creactive protein (CRP) levels. Results demonstrated an increased muscle fluid volume in the HYD condition following the infusion when compared to the CON condition. Isometric peak torque was significantly reduced following the exercise in both the HYD and CON conditions. There were no significant differences in the number of areas of muscle damage at any of the time points in either condition, with no differences between conditions. CK levels were significantly greater 24hour post exercise compared to pre, immediately and three hours post similarly in both conditions. LD in the HYD condition followed a similar trend as CK with 24 hour levels higher than pre, immediately post and three hours post and LD levels were significantly greater 24 hours post compared to pre levels in the CON condition, with no differences between conditions. A significant main effect for time was observed for CRP (p<0.05) for time, such that CRP levels increased consistently at each subsequent time point. However, CRP and IL-6 levels were not different at any of the measured time points when comparing the two conditions. Although the current investigation was able to successfully increase muscle fluid volume and an increased CK, LD and CRP were observed, no muscle damage was observed following the eccentric exercise protocol in the CON or HYD conditions. Therefore, the hypotonic infusion used in the HYD condition proved to be a viable method to acutely increase muscle fluid content in in-vivo human skeletal muscle.

Migrations and gradations : reappraising the health profile of immigrants to Canada

New immigrants to Canada typically have a more favourable health profile than the non-immigrant population. This phenomenon, known as the 'healthy immigrant effect', has been attributed to both the socioeconomic advantage (ie. educational attainment, occupational opportunity) of non-refugee immigrants and existing screening protocols that admit only the healthiest of persons to Canada. It has been suggested that this health advantage diminishes as the time of residence in Canada increases, due in part to the adoption of health-risk behaviours such as alcohol and cigarette use, an increase in excess body weight, and declining rates of physical activity. However, the majority of health research concerning immigrants to Canada has been limited to cross-sectional studies (Dunn & Dyck, 2000; Newbold & Danforth, 2003), which may mask an immigrant-specific cohort effect. Furthermore, the practice of aggregating foreign-bom persons by geographical regions or treating all immigrants as a homogeneous group may also obfuscate intra-immigrant differences in health. Accordingly, this study uses the Canadian National Population Health Surveys (NPHS) and data from the United Nations Development Program (UNDP) to prospectively evaluate factors that predict health status among immigrants to Canada. Each immigrant in the NPHS was linked to the UNDP Human Development Index of their country of birth, which uses a combined measure of health, education, and per capita income of the populace. The six-year change in health function, psychological distress, and self-rated health were considered from a population health perspective (Evans, 1994), using generalized-estimating equations (GEE) to examine the compounding effect of past and recent predictors of health. Demographic

The Smiles rearrangement in hydrazidic systems and related syntheses /|nG. A. Pawelchak. -- 260 St. Catharines, Ont. : [s. n.],

This research was directed towards the investigation of the Smiles rearrangement in hydrazidic systems and the synthesis of related heterocyclic compounds. The work can be conveniently divided into two main sections. Section 1 of the thesis relates to the synthesis and examination of the O+N migration of phenoxy- derivatives of hydrazidic halides. In general, hydrazidic halides were found to react with 2-nitrophenol and 4-nitrophenol to give corresponding a-nitrophenoxy- compounds. These a-nitrophenoxy- compounds were found to rearrange in warm base to give the corresponding N-benzoyl compounds via a proposed five-membered transition state. Experiments conducted in styrene revealed no radical contribution to the rearrangement. Cross-over product analysis indicated the rearrangement as intramolecular and consistent with the Smiles rearrangement. The preparation of N-a-chlorobenzylidene-N'-2-nitrophenyl- -N'-(2,4-dibromophenyl)hydrazine from N-benzoyl-N'-2-nitrophenyl- N'-(2,4-dibromophenyl)hydrazine was accomplished using phosphorus oxychloride. Examination of this hydrazidic chloride indicated a marked decrease .in reactivity as compared to the N-a-chlorobenzylidene-N'-phenylhydrazine case. Section 2 concerns itself with the preparation of heterocyclic compounds using an analogy of the five-membered transition state present in the Smiles rearrangement of a substituted benzylidene derivatives A new preparation of 2,4-phenyl1,3,4- oxadiazol-S-one using N-benzoyl-N'-phenylhydrazine and ethyl thiochloroformate is reported. Two new preparations of N-a-thiobenzoyl-N'-(2,4-dibromophenylhydrazine are reported using sodium hydrosulfide in conjunction with N-a-bromobenzylidene-N'-(2,4-dibromophenyl)hydrazine in the first, and phosphorus pentasulfide with N-benzoylN'-( 2,4-dibromophenyl)hydrazine in the second. The latter is preferred due to the formation of a sulfide co-product in the former. Two preparations of 2-phenyl-4-(2,4-dibromophenyl)-1,3,4- thiadiazol-S-one are reported using N-thiobenzoyl-N'-(2,4-dibromophenyl) hydrazine and ethyl chloroformate and ethyl thiochloroformate Two rapid and easy preparations of 2-phenyl-4-(2,4-dibromophenyl)- 1,3,4-triazol-S-one are reported using ethyl chloroformate and ethyl thiochloroformate. Sodium cyanate in conjunction with a-aminobenzylidene-N'-(2,4-dibromophenyl)hydrazine also provided 2-phenyl-4-(2,4-dibromophenyl)-1,3,4-triazol-S-one Section 2 concludes with an examination of two possible mechanistic routes to the prepared heterocycles.

Creating a global consciousness throught the driver model of curriculum development

The purpose of this study was to investigate the effect a human link through the One World Youth Project has on a global education program, if a human connection through the program enhances a student's ability to develop a critical consciousness of global issues, and the etTectiveness of thc constructivist-based Driver Model of Curriculum Development, which served as the curriculum model in this study. An action based research cycle was chosen as this study's research methodology and incorporated 5 qualitative data collection instruments: a) interviews and questionnaires, b) artifacts, c) teacher journal, d) critical friend's observation forms, and e) my critical friend's postobservation interviews. The data were conected from 4 student participants and my critical friend during all stages of the action research cycle. The results of this study provide educators with data on the impact of human connections in a global education program, the effects these connections have on students, and the effectiveness of the Driver Model of Curriculum Development. This study also provides practical activities and strategies that could be used by educators to develop their own global education programs. The United Nations drafted the Millennium Development Goals in an effort to improve the lives of billions of people across the globe. The eight goals were developed with the support of all member nations since all human beings are global citizens who have a responsibility to make the world a better place. Students need to develop a critical consciousness of global issues so that they can work with others to eliminate them. Students who are taught to restate the opinions of others win not be prepared to inherit a world full of challenges that will require new innovative ideas to foster positive change.

Acute endocrine responses to plyometrics versus resistance exercise in children

The purpose of this study was to examine the acute hormonal responses to a bout of resistance versus plyometric exercise in young male athletes. Specifically, changes in salivary cortisol, testosterone and testosterone-to-cortisol ratio from pre- to post-exercise between the two different exercise protocols were examined. Twenty-six peri-pubertal active boys participated in this cross-over study, completing two exercise sessions. During each session, participants first completed a 30 min control period, which did not include any exercise, and then was randomly assigned to perform a 45 min of either a resistance exercise or a plyometric exercise protocol. All participants crossed over to perform the other exercise protocol during their second exercise session, a week later. Four saliva samples during each protocol were taken at: baseline, pre-exercise, 5 min post-exercise and 30 min post-exercise. Significant increases in testosterone values were reported 5 min post-exercise following the resistance protocol, but not the plyometric protocol. Both exercise protocols resulted in significant cortisol decreases overtime, as well as significant testosterone-to-cortisol ratio increases. The post-exercise increases in salivary testosterone and testosterone-to-cortisol ratio followed the typical exercise induced anabolic response seen in adults. However, the post-exercise decrease in salivary cortisol was different than the typical adult response indicating an insufficient stimulus for this age group maybe due to their stage of the biological development. Thus, in the adolescent boys, exercise appears to change the anabolic to catabolic balance in favor of anabolism.