Prosocial Behavior and OST Activities in Youth

THESIS Presented in Partial Fulfillment of the Requirements for the Master of Education Degree in the College of Education and Human Service Professions, University of Minnesota Duluth, 2010Committee names: Diane Rauschenfels (Chair), Randy Hyman. This item has been modified from the original to redact the signatures present.A growing number of youth are engaging in extracurricular/out-of-schooltime activities. With a high percentage of youth being engaged in structured, supervised after-school settings (Ehrle & Moore, 1999a), it is important to research the effects these activities may have on adolescent development. Self-reported prosocial tendencies in early adolescents as related to out-ofschool- time (OST) activities was a concurrent, mixed-methods approach to study behavioral development. It involved youth ages 12-14 years at two schools in Polk County, MN, a county in Northwest Minnesota. Quantitative and qualitative questions were administered via paper survey about their OST activity involvement, social behaviors and social concerns. The results of the survey were analyzed to determine if a student's self-reported behavior and concerns can be linked to the activities in which they are involved.College of Education and Human Service Professions, University of Minnesota Dulut

Pollen grains in lake sediments: Pollen percentages in surface sediments from southern Michigan

Pollen in surface sediments from five lakes in southern Michigan shows evidence of differential deposition. In most lakes, pollen from ragweed occurs in a higher ratio to tree pollen in shallow-water sediment than in deep water. Pine and certain herbs with small pollen grains follow the same pattern. One very deep lake is an exception, with the ratio of ragweed to tree pollen highest in deep-water sediment. Pollen from local aquatics and from willow, which grows along the lake shore, is also unevenly distributed, occurring in highest frequencies near the parent plants. Pollen from deciduous trees, however, occurs in similar ratios at all sampling stations within each lake. Deciduous pollen occurs in uniform ratios, also in older sediment, deposited in the early 19th century, when the landscape was still forested.Percentages of deciduous tree pollen (as percent tree pollen) were compared among lakes. Single samples were taken for this purpose from the deepest part of each lake basin. Oak pollen percentages are higher in three lakes in western Washtenaw County than in three lakes in eastern Washtenaw County. This difference reflects a similar difference in present-day vegetation: second-growth oak forests grow near the lakes in the western half of the county, while all but 5% of the area in the eastern part of the county is farmland. (The difference in the ratio of farmland to forestland in the two parts of the county is not reflected clearly in the ratio of herb pollen to tree pollen, because there is so much variation within each lake.) In 140-year-old sediment, on the other hand, tree pollen percentages in the six samples are homogeneous as shown by a chi-square test. The homogeneity in sediment deposited before the forest was cleared is surprising, because witness-tree data from presettlement time show that the frequencies of tree species in the two areas were quite different. Pollen dispersal at that time must have been effective enough, to counteract differences over distances of a few tens of kilometers in the amounts and kinds of pollen produced by the vegetation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33513/1/0000011.pd

Strategies for Gait Retraining in a Collegiate Runner with Transfemoral Amputation: A Case Report

# Background More than fifty percent of people with limb amputations participate in sports or physical activity following amputation. Athletes with limb amputations may face additional challenges including phantom limb pain (PLP), psychological barriers, prosthetic complications, and gait abnormalities. Prevalence of PLP in the general amputee population is estimated to be as high as 85%. Despite the high prevalence of PLP, there is little research regarding the use of gait training as a treatment for PLP among both the general amputee population and athletes. # Case Description A 20-year old female collegiate track and field athlete presented with phantom knee pain brought on with running. The athlete demonstrated deficits in core and hip strength as well as decreased single leg stability bilaterally. Running gait analysis revealed circumduction with the prosthesis for limb advancement and increased vaulting with push off on the sound (uninvolved) limb. Gait retraining strategies were implemented to address video analysis findings and create a more efficient running gait and address phantom limb pain symptoms. # Outcomes Rehabilitation and gait retraining strategies were effective in improving several clinical and functional outcomes in this case. Significant improvements were noted in PLP, running gait mechanics, and the patient’s psychological and functional status as measured with a standardized outcome tool, the Patient-Reported Outcomes Measurement Information System^®^ (PROMIS^®^). # Discussion Running gait training following amputation could be a crucial component of rehabilitation for athletes in an attempt to lessen pain while running, especially in those experiencing phantom limb pain (PLP). Utilization of a multidisciplinary team in the gait retraining process is recommended. There is a need for further research to determine the effects of running gait retraining for management of PLP in athletes with amputation. # Level of Evidence

Role for corticoids in mediating the response of Rana pipiens tadpoles to intraspecific competition

Competition is known to decrease growth and development rate in tadpoles, but the physiological basis for this phenomenon is poorly understood. We hypothesized that competition results in increased production of stress hormones and that these hormones are responsible for the suppression of growth and development. To test this hypothesis, we measured whole-body corticosterone content in premetamorphic Leopard frog ( Rana pipiens ) tadpoles raised at two different population densities and three different food levels. Whole body corticosterone content was elevated in tadpoles subjected to either limited food (at low density) or high density. Within the low and intermediate food treatments, high density reduced tadpole growth and slowed development. Limited food slowed growth and development at all densities. Blocking corticoid synthesis by treating tadpoles with metyrapone (MTP) reversed the growth suppression caused by high density (tested in the intermediate food level treatment) but did not alter the effect of density on development rate. MTP treatment did not alter the depressive effect of limited resources on growth or development. Our results suggest that elevated corticoid biosynthesis mediates the negative effect of increased population density (i.e., increased intraspecific competition) on tadpole growth. J. Exp. Zool. 292:32–40, 2002 . © 2002 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34473/1/1140_ftp.pd