Bone properties and skeletal maturity in adolescent males, as assessed by quantitative ultrasound

ABSTRACT Background: Previous studies have implied that weight-bearing, intense and prolonged physical activities optimize bone accretion during the grow^ing years. The majority of past inquiries have used dual-energy X-ray absorptiometry (DXA) to examine bone strength and hand-wrist radiography to determine skeletal maturity in children. Recently, quantitative ultrasound (QUS) technologies have been developed to examine bone properties and skeletal maturity in a safe, noninvasive and cost-effective manner. Objective: The purpose of this study was to compare bone properties and skeletal maturity in competitive male child and adolescent athletes with minimallyactive, age-matched controls, using QUS technology. >. Methods: In total, 224 males were included in the study. The 115 pre-pubertal boys aged 10-12 years consisted of control, minimally-active children (n=34), soccer players (n=26), gymnasts (n=25) and hockey players (n=30). In addition, the 109 late-pubertal boys aged 14-16 years consisted of control, minimally-active adolescents (n=31), soccer players (n=30), gymnasts (n=17) and hockey players (n=31). The athletic groups were elite level players that predominantly trained year-round. Physical activity, nutrition and sports participation were assessed with various questionnaires. Anthropometries, such as height, weight and relative body fat percentage (BF%) were assessed using standard measures. Skeletal strength and age were evaluated using bone QUS. Lastly, salivary testosterone (sT) concentration was measured using Radioimmunoassay (RIA). Results: Within each age group, there were no significant differences between the activity groups in age and pubertal stage. An age effect was apparent in all variables, as expected. A sport effect was noted in all physical characteristics: the child and adolescent gymnasts were shorter and lighter than other sports groups. Adiposity was greater in the controls and in the hockey players. All child subjects were pubertal stage (fanner) I or II, while adolescent subjects were pubertal stage IV or V. There were no differences in daily energy and mineral intakes between sports groups. In both age groups, gymnasts had a higher training volume than other athletic groups. Bone speed of sound (50s) was higher in adolescents compared with the children. Gymnasts had signifieantly higher radial 50S than controls, hockey and soccer players in both age cohorts. Hockey athletes also had higher radial 50S than controls and soccer players in the child and adolescent groups, respectiyely. Child gymnasts and soccer players had greater tibial 50S compared with the hockey players and control groups. Likewise, adolescent gymnasts and soccer players had higher tibial SoS compared with the control group. No interaction was apparent between age and type of activity in any of the bone measures. » Lastly, maturity as assessed by sT and secondary sex characteristics (Tanner stage) was not different between sports group within each age group. Despite the similarity in chronological age, androgen levels and sexual maturity, differences between activity groups were noted in skeletal maturity. In the younger group, hockey players had the highest bone age while the soccer players had the lowest bone age. In the adolescent group, gymnasts and hockey players were characterized by higher skeletal maturity compared with controls. An interaction between the age and sport type effects was apparent in skeletal maturity, reflecting the fact that among the children, the soccer players were significantly less mature than the rest of the groups, while in the adolescents, the controls were the least skeletally mature. Summary and Conclusions: In summary, radial and tibial SOS are enhanced by the unique loading pattern in each sport (i.e, upper and lower extremities in gymnastics, lower extremities in soccer), with no cumulative effect between childhood and adolescence. That is, the effect of sport participation on bone SOS was apparent already among the young athletes. Enhanced bone properties among athletes of specific sports suggest that participation in these sports can improve bone strength and potential bone health.

Acquisition and transfer of experiential learning from rock climbing to the corporate workplace

There were three purposes to this study. The first purpose was to determine how learning can be influenced by various factors i~ the rock climbing experience. The second purpose was to examine what people can learn from the rock climbing experience. The third purpose was to investigate whether that learning can transfer from the rock climbing experience to the subjects' real life in the workplace. Ninety employees from a financial corporation in the Niagara Region volunteered for this study. All subjects were surveyed throughout a one-day treatment. Ten were purposefully selected one month later for interviews. Ten themes emerged from the subjects in terms of what was learned. Inspiration, motivation, and determination, preparation, goals and limitations, perceptions and expectations, confidence and risk taking, trust and support, teamwork, feedback and encouragement, learning from failure, and finally, skills and flow. All participants were able to transfer what was learned back to the workplace. The results of this study suggested that subjects' learning was influenced by their ability to: take risks in a safe environment, fail without penalty, support each other, plan without time constraints, and enjoy the company of fellow workers that they wouldn't normally associate with. Future directions for research should include different types of treatments such as white water rafting, sky diving, tall ship sailing, or caving.

The carbon disclosure project, an evolution in international environmental corporate governance : motivations and determinants of market response to voluntary disclosures

This paper examines the factors associated with Canadian firms voluntarily disclosing climate change information through the Carbon Disclosure Project. Five hypotheses are presented to explain the factors influencing management's decision to disclose this information. These hypotheses include a response to shareholder activism, domestic institutional investor shareholder activism, signalling, litigation risk, and low cost publicity. Both binary logistic regressions as well as a cross-sectional analysis of the equity market's response to the environmental disclosures being made were used to test these hypotheses. Support was found for shareholder activism, low cost publicity, and litigation risk. However, the equity market's response was not found to be statistically significant.

O.S. Rixford Manufacturing Company corporate stock book, 1883-1898.

Around 1837, Luther Rixford founded a tool manufacturing business (originally known as the Luther Rixford Manufacturing Co.) in East Highgate, Vermont, that specialized in manufacturing scythes and other agricultural tools. A branch of this business was established in Upper Bedford, Quebec, around the late 1840's. Subsequent generations of the Rixford family took over the operations of both facilities, and in 1857 Oscar S. Rixford renamed the company the O.S. Rixford Manufacturing Co. The company was incorporated in 1883. Around 1920, the O.S. Rixford Manufacturing Company (of Canada) was acquired by Welland Vale Manufacturing, in St. Catharines, Ontario. The Rixford Company in Vermont continued operations until 1956, when decreasing demand for the tools they manufactured caused them to close their doors.

CEO Compensation, Compensation Risk, and Corporate Governance: Evidence from Technology Firms

Literature suggests that CEOs of technology firms earn higher pay than CEOs of non-technology firms. I investigate whether compensation risk explains the difference in compensation between technology firms and non-technology firms. Controlling for firm size and performance, I find that CEOs in technology firms have higher pay, but also have much higher compensation risk compared to non-technology firms. Compensation risk explains the major part of the difference in CEO pay. My study is consistent with the labor market economics view that CEOs earn competitive risk-adjusted total compensation.

The Informational Value of Corporate Credit Ratings

This thesis examines the quality of credit ratings issued by the three major credit rating agencies - Moody’s, Standard and Poor’s and Fitch. If credit ratings are informative, then prices of underlying credit instruments such as fixed-income securities and credit default insurance should change to reflect the new credit risk information. Using data on 246 different major fixed income securities issuers and spanning January 2000 to December 2011, we find that credit default swaps (CDS) spreads do not react to changes in credit ratings. Hence credit ratings for all three agencies are not price informative. CDS prices are mostly determined by historical CDS prices while ratings are mostly determined by historical ratings. We find that credit ratings are marginally more sensitive to CDS than CDS are sensitive to ratings.

The Impact of a Corporate Name Change on Stock Price and Trading Volume of Canadian Companies

This thesis examines the impact of a corporate name change on stock price and trading volume of Canadian companies around the announcement date, the approval date, and the adoption date over the time period from 1997 to 2011. Name changes are classified into six categories: major and minor, structural and pure, diversified and focused, accompanied with a change in ticker symbol and without a change in ticker symbol, “Gold” name addition and deletion, and different reasons for name changes (e.g., merger and acquisition, change of structure, change of strategy, and better image). The thesis uses the standard event study methodology to perform abnormal return and trading volume analyses. In addition, regression analysis is employed to examine which type of a name change has the largest impact on cumulative abnormal returns. Sample stocks exhibit a significant positive abnormal return one-day prior to the approval day and one day after the adoption date. Around the approval date we observe significant abnormal returns for stocks with a structural name change. On the day after the adoption date we document abnormal returns for stocks with major, minor, structural, pure, focused, and ticker symbol name changes. If a merger or acquisition is the reason for a name change, companies tend to experience a significant positive abnormal return one-day before the approval date and on the adoption date. If a change of structure is the reason for a name change, companies exhibit a significant positive abnormal return on the approval date and a significant negative abnormal return on the adoption date. In case of a change of strategy as the reason for a name change, companies show a significant negative abnormal return around the approval date and a significant positive abnormal return around the adoption date.

Corporate Social Responsibility, Corporate Governance, And Managerial Risk-Taking

This dissertation investigates the association between corporate social responsibility (CSR) and managerial risk-taking, as well as the differences in governance structure that affect this association. Using a sample of US public firms from 1995 to 2009, we find that firms with strong CSR records engage in higher risk-taking. Furthermore, we find that this relationship is robust when accounting for differences in governance structure and correcting for endogeneity via simultaneous equations modeling. Additional testing indicates that performance in the employee relations dimension of CSR in particular increases with risk-taking, while high firm visibility dampens the association between CSR and the accounting-based measures of risk-taking. Prior literature establishes that high managerial risk-tolerance is necessary for the undertaking of risky yet value-enhancing investment decisions. Thus, the main findings suggest that CSR, rather than being a waste of scarce corporate resources, is instead an important aspect of shareholder value creation. They contribute to the debate on CSR by documenting that corporate risk-taking is one mechanism among others through which CSR maps into higher firm value.

"Everyone Loves Marineland!" (?): Entertainment Animal Advocacy, Praxis, and Resisting Corporate Repression

Following allegations and graphic evidence of animal cruelty and neglect documented by ex-employee whistleblowers of Marineland Canada to the Toronto Star newspaper in late 2012, the ethics surrounding animal captivity have been increasingly contested in regional public discourse. Animal advocates in the Niagara region and beyond have been compelled to demand change at the infamous local captive animal park— whether it be welfare-oriented reform, or radical animal liberation. With this as a backdrop, this research explores the ideologies, experiences, and strategic tactics of anti-Marineland animal advocates; the sociopolitical issues surrounding the largely unexamined but serious issue of imprisoned animals as entertainers; and the ensuing governmental and corporatist attempts to squash dissent of anti-Marineland critics. Situated within a Critical Animal Studies theoretical paradigm as well as a flourishing global anti-captivity critique inspired by the film Blackfish, this project employs semi-structured interviews and participant observation methodologies to analyze advocates' views on captivity under capitalism and the effectiveness of their praxes. Finally, this research illuminates the nuances of the conventionally-upheld dualistic theoretical debate of animal welfare versus animal rights within zoo and aquaria entertainment contexts through an exploratory examination of advocates' complex ideological views.

Statement that Dr. Richard S. King became accountable for a Debt Owed to him by Dilly Coleman

Statement of Frederick Dilke of Port Robinson that Dr. Richard S. King became accountable for a debt owed to him by Dilly Coleman. The debt was assumed by Dr. Richard S. King, Sept. 24, 1850.

The Backing of Government Debt and the Price Level

This paper studies the interdependence between fiscal and monetary policies, and their joint role in the determination of the price level. The government is characterized by a long-run fiscal policy rule whereby a given fraction of the outstanding debt, say d, is backed by the present discounted value of current and future primary surpluses. The remaining debt is backed by seigniorage revenue. The parameter d characterizes the interdependence between fiscal and monetary authorities. It is shown that in a standard monetary economy, this policy rule implies that the price level depends not only on the money stock, but also on the proportion of debt that is backed with money. Empirical estimates of d are obtained for OECD countries using data on nominal consumption, monetary base, and debt. Results indicate that debt plays only a minor role in the determination of the price level in these economies. Estimates of d correlate well with institutional measures of central bank independence.

Valuing Sovereign Default Risk - A Pricing Formula and its Empirical Results for the Mexican External Debt.

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