The use of diatom assemblages to determine paleotrophic changes in lakes

The purpose of this study was to develop a classifi cation scheme for l ake trophic status based on the relative abundance of l ake sediment diatom trophic indicator species. A total of 600 diatom frustules were counted from the surface sediments of e a ch of 30 lakes selected to repr e seni~ a continuum from u.lt ra-oligotrophic t,o fairly eutrophic but not hype r-' eutrophic conditions. Published autecological information was used to determine the trophic indicator status of each of the s pecies. A quotieht was derived by dividing the s um of all the e utrophic indicator species by the sum of all oligotrophic indicai.-:.or species. Oligo'- mesotrophic. mesotrophic and meso-eutrophic species were added to both the numerator and denomina tor. Five categories of diatom i.nferred trophic status were recognized : ultra-oligotrophic - 0'-0.2:3, oligotrophic::: 0.24-0 . 70, mesotrophic :: 0.'71 -0.99, meso-elxtrophic :: 1. 00-1. '78 and eutrophic:: 1.. 79-2. 43. But only three of these (oligotrophic:: 0-0.69, mesotrophic ::: 0 . 70'-1.69 j and eutrophic:: 1.70-2.50) proved usef ul. The present study of the relationship between diatom inferred trophic status and the literature-derived trophic status of SO lake s (which were purposely chosen to represent a broad spectrum of lakes in Canada) indicated that: 1) Based on diatom species (assemblages ) it is possible to segregate the lakes from which. th",)se diatoms were taken into three basic categories : o ligotrophic, mesotrophic and eutrophic lake types. ~~) It was not possible t,o separate meso-eutrophic and o l igo-mesotrophic lakes f rom mesotrophic l akes as the the degree of overlap betwee n the diat,om species in these lake types was extremely high. 3) Ha d mo r e ul tra-oligotroph,ic lakes been sampled it might have been possible to more a ccurately s eparate them f rom oligotrophic Jakes. 4 ) Had. more humic lakes been sampled in this s tudy I f eel it would have been possible to identify a unique diatom a ssemblage which would h a ve chara cterized t his lake type . Re gression analyses were performed using the aforementioned diatom inferred trophic index as a f unction of 1) log Sec chi transparency (r = - 0.70) 2) total phosphorus (r = 0. 77 ) and 3) chlorophyll-a (r = 0.74). Once e ach of these rel ationships had been established , it was possible to infer paleotrophic (downcore) changes in an oligotrophic lake (Barbara Lake) and in a eutrophic lake (Chemung Lake) . Barbara Llake was dominated by oligotrophic s pecies and remained oligotrophic throughout the 200-·year history r epresented by i t s 32 em long sediment core. Chemung Lake is currently dominated. by eutrophic species but went through a mesotrophic st,age which was associated with a rise in the water level of the lake followi n g dam construction in its watershed in the early 1.900 J ::;. This was followed by its reversion to it,s present day eutrophic stage (dominated by eutrophic species) possibly as a r esult of shallowing process which can be attributed to " silting' up" of the reservoir and the invasion of the l ake by Myriophyllum spjcatum (Eurasian milfoil) i n the 1970's . In addition, nutrient .:r':l.ch run"'offwhich resulted from increased human a.ctivities associated with cottage development along its shores has contribut ed to its eutrophication. There is some evidence that the rat,e o :f its prog ressive eutrophication has declined during the last decade. This was correlated with legislation enacted in the 60's and 70's in Ontario which was aimed at reducing nutrient loading from cottages.

Correspondence between the American and British Plentipotentiaries relative to the commercial convention concluded on the 3rd of July, 1815.--

January 16, 1816.

Letter from the acting Secretary of War, transmitting information relative to the claims of the State of Massachusetts for payment of the expenses of the militia ordered out by the executive authority of the state, during the late war. --

15th Congress, 1st session, 1817-1818, House. Doc. 81.

Letter from the Secretary of War, transmitting documents containing the information required by the resolution of Mr. Wright, on the 22d inst. relative to the execution of the act fixing the military peace establishment. --

14th Congress, 1st session, 1815-1816. House. Document no. 33.

Message from the President of the United States, transmitting documents relative to the commencement and progress of any acts or system of retaliation upon prisoners of war, by the Governments of Great Britain and the United States. --

13th Congress, 3d session. House. Doc. no. 13.

Message from the President of the United States, transmitting a report of the Secretary of State, in obedience to a resolution of the thirteenth inst. "requesting the President to lay before this House such documents relative to the Russian mediation as in his opinion it may not be improper to communicate." --

United States,13th Congress, 2d session, 1813-1814. House. Doc. no. 35.

Report of the Committee on Military Affairs, on the differences that exist, between the United States and some of the individual States, respecting the relative powers of the general and state governments over the militia.--

February 28, 1815. Printed by order of the Senate of the United States.

Report of the Committee to whom was Referred the Correspondence between Mr. Monroe and Mr. Canning, and between Mr. Madison and Mr. Rose, relative to the attacked of Chesapeake : and also a communication from the President of the United States of the 30 March last, with a letter from Mr. Erskine to the Secretary of State, and a letter from M. Champagny to Gen. Armstrong.--

April 16, 1808. Printed by Order of the Senate.

Relative importance of body composition, osteoporosis- related behaviours and socioeconomic status on bone SOS in adolescent females

The purpose of this study was to examine the associations between bone speed of sound (SOS) and body composition, osteoporosis-related health behaviours, and socioeconomic status (SES) in adolescent females. A total of 442 adolescent females in grades 9-11 participated. Anthropometric measures of height, body mass, and percent body fat were taken, and osteo-protective behaviours such as oral contraceptive use (OC), physical activity and daily calcium intake were evaluated using self-report questionnaires. Bone SOS was measured by transaxial quantitative ultrasound (QUS) at the distal radius and mid-tibia. The results suggest that fat mass is a significant negative predictor of tibial SOS, while lean mass is positively associated with radial SOS scores and calcium intake was positively associated with tibial SOS scores (pnally, users of OC had higher radial SOS. No significant correlation was found between physical activity and bone SOS. Therefore bone strength measured by QUS is reduced in adolescents with an increased fat mass, and influenced positively by OC use, calcium intake and lean mass.

Analyzing the learning of the taking personal and social responsibility model within a new physical education undergraduate degree program in El Salvador

EI Salvador presents an unfortunate history that includes a military regime and a civil war that together created a legacy of violence in which the country still struggle nowadays. Salud Escolar Integral (SEI) was created in 2005 as a program to combat youth violence throughout the re-formulation of physical education (PE) classes in public schools, promoting life skills learning that supports the resolution of conflicts with nonviolent ways. In 2007, SEI supported the creation of a physical e~ucation teacher education (PETE) degree at the Universidad Pedag6gica de EI Salvador (UPES), having the goal to assist pre-service teachers with a better understanding of humanistic principles. The present research analyzed if after attending all three years ofUPES PETE program, students presented high self-perception levels of competence and confidence related to attitude, skills and knowledge to teach PE within humanistic principles. Taking Personal and Social Responsibility (TPSR) was the theoretical framework used to analyze the development of humanistic principles. The study had a mixed-method longitudinal design that included questionnaires, reflection templates and interviews. In conclusion, although it is suggested that UPES should provide better support for the development of the teaching principles of empowering students and transfer learning, most of the humanistic principles were highly promoted by the program. At last, it is suggested that future research should track teachers' progress while teaching in schools, in order to analyze if the theory of promoting humanistic principles have also become a daily practice.

The effect of an eight session skate treadmill and agility training program on the degree of separation in ice hockey players

The sport of ice hockey places multiple simultaneous demands on the physiological, mechanical, and cognitive abilities of individual players. The purpose of the study was to investigate the effect of an eight session degree of separation (DOS) training intervention on sport specific measures of skating, stick handling and puck control movements in competitive ice hockey players. All participants completed a battery of pre and pos t skill and DOS specific tests designed to evaluate DOS abilities: Ttest of agility, a modified Cunningham Faulkner test of anaerobic capacity performed on a skate treadmill and a DOS skate treadmill test. Statistically significant differences were found between groups on the post test scores, meaning that the training intervention had a specific effect on the post test scores of the experimental group (p~O.05). Results of this investigation suggested that a DOS specific training program has the potential to enhance the integration and automation of or sequencing and coordination of uncoordinated ice hockey movements.

Photograph of Bell Family Relative [n.d.]

Small black and white photograph mounted on black card of an unidentified Bell family relative, possibly a sibling of Irene Bell, whose photo is similarly featured. This undated photograph was in the possession of the Rick Bell family, whose relatives include former Black slaves from the United States.According to the 1911 Census of Canada, Irene Bell had the following siblings: Ernest Bell, born 1889 Archie Bell, born 1895 Allen Bell, born 1901 Kenneth Bell, born 1910

Unidentified Sloman relative [n.d.]

This undated photograph features an unidentified Sloman family relative pictured outside of a house in an unknown location. The photograph was among the family memorabilia retrieved from the attic of Iris Sloman Bell, of St. Catharines, in the 1980s. The Sloman - Bell family has descendants who are former Black slaves from the United States who settled in southern Ontario.